The links below provide some information on EM Technology® for Bioremediation. For a full database of research papers on Effective Microorganisms®, please visit EMRO Japan's website.
Application of Effective Microorganisms in a New
Hybrid System of Biogas Production
Assessment of Using Chemical Coagulants and Effective Microorganisms In Sludge Dewaterability Process Improvement
M. S. Shihab
Department of Civil Engineering, University of Mosul,
College of Engineering, Mosul, Iraq
Abstract: The feasibility of using a combination of Effective Microorganisms™(EM) and conventional chemical conditioner was evaluated in this study to assess and discern the dewatering properties of the secondary sludge which was produced from wastewater treatment plant of the medical assebly in Mosul City. Conventional coagulants such as lime, alum and ferrous sulfate, or six doses for each coagulant type i.e., 5-30, 10-60 and 25-150 mg L -1, respectively, were used in the sludge conditioning processes for the enhancement of the sludge dewatering capacity. The characteristics of the conditioned sludge at each dose, such as Specific Resistance to Filtration (SRF), were determined. Experimental results indicated that EM seeds had a passive effect on SRF value which was about 71.4 and 75% in lime and ferrous sulfate respectively. While in the alum conditioning process, a significant effect on SRF reduction was accomplished which was about -47.9 and -32.8% for EM and alum dose increments, respectively. The optimum alum dosage, which gave minimum SRF 0.98348x1012 m kg-1, was 60 mg L -1 at 1% EM. However, a suitable linear relationship has been found to describe the variation of EM and coagulants dosage as a function of SRF.
Formulation of Effective Microbial Consortia and its Application for
S Monica, L Karthik, S Mythili and A Sathiavelu*
School of Biosciences and Technology, VIT University, Vellore, India
The present study was conducted for sewage treatment using effective microbial consortium. The Effective Microorganisms (EM) like Lactobacillus, Pseudomonas, Aspergillus, Saccharomyces and Streptomyces were isolated from respective sources. The microbial consortium was formulated using molasses as medium at pH 3.8 and incubated at 37°C for 3 days. The sewage treatment was carried out with the addition of 3 ml/l EM solution under aerobic condition. The BOD, COD, TDS and TSS were reduced by 85%, 82%, 55%, and 91% respectively after 3 days of treatment. The results showed that the formulated EM was efficient for sewage treatment and thereby it reduced the environmental impact.
Keywords: Effective Microorganisms; Molasses; Optimization; Sewage; BOD; COD; TDS; TSS
Abbreviation: EM: Effective Microorganisms
Sewage treatment is one of the major problems faced by municipalities. Sewage is the wastewater comprising 99.9% water and 0.1% solid particles. The domestic sewage has high amount of organic and inorganic pollutants . The untreated sewage causes foul smell . The improper disposal of sewage causes pollution and destroys the aquatic organisms due to high organic content and biological oxygen demand (BOD) concentration . So, the sewage has to be treated to reduce the environmental impact. The chemically treated water causes harmful effects due to toxic chemicals than the organisms which are originally present in the sewage . The organisms present in wastewater degrade organic matter  and helps for further treatment. In conventional treatment method, bacteria remove the organic content of wastewater but the solid particle remains as sludge. The sludge can be used as fertilizer or incinerated, disposed into ocean or landfill. The conventional sewage treatment processes are expensive to operate and maintain  and causes pollution.
Effective Microorganism (EM) is the consortia of beneficial and naturally occurring microorganisms which are not chemically synthesized or genetically modified. The EM technology was developed by Professor Dr. Teruo Higa at University of Ryukus, Okinawa, Japan in 1970s. The EM solution is the blending of effective microorganisms in molasses at low pH. Initially EM was developed to increase the crop yield by enhancing the soil activity . But later, it has its application in wastewater treatment . The EM has its wide application in the field of agriculture, natural farming, livestock, gardening, composting , bioremediation , algal control and prawn culture. The EM suppresses soil borne pathogen and pest, promotes plant growth, improves soil fertility and yield of crops and used as feed additive for livestock. The EM treated sludge is used as fertilizer and the EM treated waste water is used in crop production as it is enriched with beneficial microorganisms .
The EM secretes organic acids and enzymes which acts on sewage and degrades complex organic matter into simpler ones . The antioxidant substances produced by EM enhances the breakdown of solids and reduces the sludge volume . Missouri river in Jefferson City, North America was polluted by run off from industries and cities and generates foul odour. The application of EM for one month reduced the foul odour . In Thailand, EM was sprayed 3 to 4 times on 3000-4000 metric tons of garbage which were dumped daily at a site just outside Bangkok in Ladkra Bhan. The EM reduced the foul odour and flies .
The EM used in this study comprises Lactobacillus, Pseudomonas, Aspergillus, Saccharomyces and Streptomyces. The lactic acid bacteria enhance the breakdown of organic matter such as lignin and cellulose. Yeast produces antimicrobial substances and their metabolites are used as substrate for lactic acid bacteria and actinomycete. The bioactive substance produced by yeast promotes plant growth. Pseudomonas releases bioactive compounds which act on the sewage and precipitates or detoxifies the metal. Aspergillus decomposes organic matter rapidly and produces alcohol, esters and antimicrobial substances. Actinomycete produces antimicrobial substances from amino acids derived from organic matter for suppressing harmful fungi and bacteria.
The main objective of this study was to develop low cost and eco- friendly sewage treatment process using effective microbial consortia.
Materials and Methods Collection of samples
The respective samples were collected for isolation of various microorganisms. The curd sample was used for isolation of Lactobacillus. The oil spilled soil and moist soil at the depth of 10 cm was aseptically collected in a sterile polythene bag from VIT University, Vellore, Tamil Nadu for isolation of Pseudomonas and Streptomyces, respectively. The dry yeast granules were used for isolation of Saccharomyces. The boiled rice sample was maintained in closed container for 3 days under sterile condition until the fungal mat was observed and used as inoculum for isolation of Aspergillus. The samples were refrigerated at 4°C for further use.
Isolation of effective microorganisms
The curd sample and oil spilled soil sample were serially diluted, 10-4, 10-5 and 10-6 dilutions of sample were inoculated on de Man Rogosa Sharpe Agar and King’s B Agar and incubated at 37°C for 24 hours to isolate Lactobacillus and Pseudomonas, respectively. The moist soil sample was serially diluted, 10-3, 10-4 and 10-5 dilutions were inoculated on Kenknight’s Agar and incubated at 37°C for 3 days to isolate Streptomyces. The obtained inoculum from rice was inoculated on Czapek’s Dox Agar by hyphal tip technique and incubated at 28°C for 3 days to isolate Aspergillus. The loop full of inoculum was inoculated on Potato Dextrose Agar and incubated at 37°C for overnight period to isolate Saccharomyces. The obtained colonies were subcultured to get pure culture as described by Cappuccino and Sherman .
Characterization of effective microorganisms
The isolates were identified by morphological and biochemical studies. Biochemical tests like catalase test, oxidase test, IMViC test, sugar fermentation tests, Triple Sugar Iron test, urease test and hydrolysis tests were performed as described by Cappuccino and Sherman .
Formulation of EM
The isolated microorganisms were cultured together in a medium (molasses) at various pH, temperature and concentration of molasses. The optimal physical conditions for formulating EM was analysed by culturing microbial consortia at pH of 6.5-8, temperature of 28°C and 37°C and molasses concentration of 1-10%.
Sewage treatment using EM
The raw sewage sample was collected from VIT University, Vellore, Tamil Nadu. The floating particles were removed from sample and collected in a clean container. The container was washed using sodium hypochlorite and water followed by rinsing of sample before collection. 20 litres of sewage water was collected, divided into six equal parts and maintained one as control and rest five for inoculating different concentrations of EM. The pH, total dissolved solids (TDS), total suspended solids (TSS), biological oxygen demand (BOD) and chemical oxygen demand (COD) of sample were analysed according to the standard protocol of APHA  within 2 hours of collection. Then the formulated EM solution was added to sewage at various concentration ranged from 1-10 ml/l. The EM inoculated water was analysed daily to determine the effect of EM in treating sewage.
All the experiments were done in triplicates. The data was analysed statistically using Microsoft Excel 2007 and reported as mean ± standard deviation (SD).
Results and Discussion
Characterization of EM
The isolated microorganisms were characterized according to Bergey’s manual (Table 1). Erdogrul and Erbilir  stated that Lactobacillus is gram positive rods, catalase and oxidase negative. Pseudomonas was identified as gram negative motile rods and showed positive for catalase, oxidase and citrate tests . Praveen and Jain  reported that Streptomyces is gram positive rods and can hydrolyse casein. The species of Streptomyces exhibited variation in colour of substrate mycelium depending on the media composition .
Table 1: Characteristics of Effective Microorganisms
Formulation of EM
Effect of pH and temperature: The growth of EM was observed at pH of 6.5 to 8 and temperature of 28°C and 37°C. The Pseudomonas may grow in a wide pH range of 4-10 at 27°C and 37°C but the optimal condition is pH 8 and 37°C . The fungal species isolated from Antarctic soil was observed to grow at temperature between 4°C and 35°C and exhibited variation in growth pattern . Praveen and Jain  stated that Streptomyces sampsonii shows its growth at pH of 5-10 and temperature of 15-42°C.
Effect of molasses concentration: The growth of microbial consortia was observed at various molasses concentration of 1-10%. The lowest concentration of molasses facilitated the growth of EM and the increased concentration inhibited the growth and survival of EM. It is observed from Table 2 that 1% to 3% of molasses is favourable for EM. The growth of Lactobacillus and Saccharomyces was observed even at highest molasses concentration of 10%. The growth inhibition may be due to osmotic pressure created by molasses. 8.2
Effect of incubation period: The incubation period has greatest effect on microbial consortia formulation. At longer incubation period, the growth of microorganisms was inhibited due to depletion of nutrients, accumulation of toxic end products and change in pH. The optimal incubation period was 72 hours as growth of all the five 7.4 organisms was observed (Table 3).
The pH is an important parameter for preparation of EM solution. Figure 1 depicts the variation in pH of EM solution during incubation. The pH was decreased from 7 to 2.9 in 5 days of incubation by fermenting the molasses. After 5 days of incubation, the pH was constant as the organisms utilised the entire energy source and there was no further growth of organisms. The organisms was not able survive at high acidic pH; hence EM solution was used after 3 days of incubation (pH 3.8).
Analysis of EM treated sewage
Biological oxygen demand: The EM reduced the BOD of sewage from 374.5 to 55.9 mg/l with mean reduction of 85%. The EM showed the effective result when compare to control while treated at a concentration of 3 ml/l for 3 days. The control showed the decrease in BOD from 374.5 to 248.6 mg/l in 5 days (Figure 3). The acetogenic bacteria strain BP103 reduced the BOD by 58.5–82.2% . Mongkolthanaruk and Dharmsthiti  formulated bacterial consortium including Pseudomonas, Bacillus and Acinetobacter using molasses for treating lipid rich wastewater and the consortium reduced BOD from 448 to 72 mg/l. Kumar  used the bacterial consortium of Pseudomonas aeruginosa, Bacillus megaterium and Stenotrophomonas maltophilia for treating paper and pulp mill effluent and observed BOD reduction from 87 to 89%.
Figure 2: Effect of EM treatment on pH of sewage
Figure 3: Effect of EM treatment on BOD reduction of sewage
Chemical oxygen demand: The EM reduced the COD of sewage from 570.4 to 99.8 mg/l with mean reduction of 82%. The EM reduced the COD effectively while treated at concentration of 3 ml/l for 3 days. The control showed the decrease in COD from 570.4 to 409.3 mg/l in 5 days (Figure 4). The EM reduced the COD of wastewater from Nestle and Trebor companies to 76% in 11 days at a concentration 1 ml/l . The acetogenic bacteria strain BP103 reduced the COD by 35.5–71.2% . Stanley  reported that whey disposed from cheese manufacturing industry was treated using Kluyveromyces fragilis which reduced the COD by 29% and 37% in 16 and 20 hours, respectively after the growth of culture. Kumar  used the bacterial consortium of Pseudomonas aeruginosa, Bacillus megaterium and Stenotrophomonas maltophilia for treating paper and pulp mill effluent and observed COD reduction from 67% to 71%. The consortium of five white-rot fungi, Phanerochaete chrysosporium, Pleurotus ostreatus, Lentinus edodes, Trametes versicolor and S22 removed 71% of lignin content and 48% of COD from wastewater .
Figure 4: Effect of EM treatment on COD reduction of sewage
Total dissolved solids: The EM reduced the TDS of sewage from 2460 to 1084 mg/l with mean reduction of 55%. The EM showed the effective reduction of TDS while treated at concentration of 3 ml/l for 3 days. The control showed the decrease in TDS from 2460 to 2309 mg/l in 5 days (Figure 5).
Total suspended solids: The EM reduced the TSS of sewage from 486.6 to 43.3 mg/l with mean reduction of 91%. The EM showed the effective reduction of TSS while treated at concentration of 3 ml/l for 3 days. The control showed the decrease in TSS from 486.6 to 433 mg/l in 5 days (Figure 6). The acetogenic bacteria strain BP103 reduced the total solid content by 59.1% . Okuda and Higa  used EM to reduce the total solid content of wastewater by 94%.
pH: The EM did not show any considerable change in pH of sewage. The fluctuation in pH was due to the natural environmental factors (Figure 2).
At higher concentration of EM, the BOD and COD was increased due to high microbial population. Hence 3 ml/l is the efficient concentration of EM for the effective treatment of sewage. After 3 days of treatment, the dissolved oxygen was decreased due to depletion of nutrients. So the treated water has to be left for chlorination.
The white rot fungi and brown rot fungi in presence of glucose reduced the BOD and COD of wastewater. If Streptomyces is cultured along with these fungi there was increase in the decolourisation to 85% . The microorganisms exhibit efficient treatment in consortium than the sole organism.
The COD, BOD, TDS and TSS reduction of domestic wastewater by sedimentation, aeration, activated sludge and sand filter was 92.17%, 97.66%, 32.38% and 97.58%, respectively . The sludge released by these process causes environmental impact and also it is expensive. But there is no release of sludge in EM treatment and the sewage can be treated economically.
The Effective Microbial consortium was formulated and its efficiency for sewage treatment was studied. The results showed that the EM treatment of sewage reduced BOD, COD, TDS and TSS by 85%, 82%, 55% and 91% respectively. The malodour and turbidity of sewage was reduced. The treatment process is highly viable and economical. The EM treated water is non-toxic and safe to dispose as it contains beneficial microorganisms. The EM reduces the environmental impact of conventional methods.
Authors wish to thank management of VIT University, Vellore, TN, India, for providing necessary facilities and support for the completion of this work.
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Copyright: © 2011 Monica S, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Full Text available: http://www.omicsonline.org/1948-5948/JMBT-03-051.pdf
Upgrading up Flow Anaerobic Sludge Blanket Using Effective Microorganisms
El karamany, H. M.1, Nasr, A. N.1, and Ahmed, D. S1. 1 Environmental Engineering Department, Faculty of Engineering, Zagazig University, Zagazig, Egypt
Abstract - The up-flow anaerobic sludge blanket UASB concept relies on high levels of biomass retention through the formation of granules sludge. In recent year, numerous designs and/or configurations of these reactors have been developed to optimize the anaerobic treatment of wastewater. The system can afford treatment for high strength wastewater at low energy requirement, low operational cost and low sludge production as well. Among the limitation of the UASB system are their limited treatment efficiency and the long start up phase.
The main objectives of the present search is to study the effect of seeding Effective Microorganism (EM•1) upon the UASB reactor treatment efficiency and establishes the optimum seeding dose and examine the seeding frequency.
A pilot scale model was built simulating the UASB reactors and seeded with EM•1 for four runs. In the first three runs the EM•1 was seeded to the reactor on a daily base with volumetric rate of 0.21 %, 0.42 % and 0.85 %. In the fourth run the EM1 was seeded once with volumetric rate of 10.6 %.
Based on the experimental program, it was found that, there was a remarkable improvement in COD and SS removal ratios by seeding with EM•1. The best COD removal efficiency achieved was 99% for EM•1 seeded at volumetric rate of 0.85% of the reactor volume. The study showed that the daily seed of the EM•1 is recommended than the batch feeding regime.
For the full document, click here, to download the pdf from an external site.
In May of 2005, the City of Meridian, Texas DCALA, Ltd., conducted a 30-Day trial to assess the ability of EM-1® Waste Treatment to control odor, grease, and phosphorus levels within the city's wastewater collection and treatment system. Activated EM-1® was applied through an injection pump. The application rate was calculated based on the loading and volume of influent. Odor was eliminated within 2 hours of the first application and did not return until after the trial had completed. Grease solids that were visible on lift station walls were digested within the first week of applications. Phosphorus levels from dropped from 3.92 to 0.13 during the 4-week trial.
Grease and odor were the primary concerns of the City. As the local area has quite a bit of dairies and processing plants, phosphorus reduction is another major concern. The objective was to see if EM-1® could reduce odors and phosphorus without dramatically increasing costs for treatment to the city.
The total flow and loading rates were supplied by the City of Meridian. EM-1® was activated according to the directions on our website. Applications were done on a daily basis at one lift station. The feed rate was a ratio of 1 part Activated EM-1® Waste Treatment per 10,000 gallons of wastewater per day.
Not all data was available from the city records. Perhaps the numbers were not collected.
BOD is almost identical as the previous year's analysis. Influent data is available only for two weeks of each month. The two numbers from the third week of April and first week of May are 203 and 192 respectively. All influent measurements of BOD for the rest of May and June are lower than 170. Perhaps will a longer trial going on for several more months an effect on BOD could have been determined.
A significant drop in Total phosphorus was achieved. Levels of Total phosphorus did jump back immediately after ceasing application of EM-1® Waste Treatment, demonstrating the EM-1® applications had an impact on total phosphorus levels.
Residual effects remained on DO for about two weeks after EM-1® Waste Treatment applications perhaps a sign of residence time of microbes.
Review of the 2004 data on TSS show a trend that the TSS is not stable. During the month of EM-1® Waste Treatment applications, the TSS dropped during the first week and remained low and stable during the rest of the month. Perhaps continued applications would have maintained this. EM-1® Waste Treatment has been studied in several fields for its applications on controlling EC. EC is directly related to TSS and charged particles tend to stay in suspension. By dropping the EC, suspended solids drop out and TSS drops. Most data on EM-1® Waste Treatment applications will demonstrate about a 50% drop in TSS on average, cutting polymer usage by about 50% in the sludge handling side of treatment. This drop in EC also is demonstrated in the ability of EM-1® Waste Treatment to remove calcium buildup in piping and on equipment.
This project demonstrated the ability of EM-1® to deodorize the collection and treatment system, digest (not emulsify) grease, and reduce total phosphorus through the injection on one product. The most significant cost savings in applications of EM-1® is that capital outlay for new equipment is nominal. If the municipality wishes to purchase the injection systems, they can be purchased for as little as $200 per unit.
The application of EM-1® into lift stations prevents corrosion from sulfuric acid, therefore cleaning the units and increasing the life of the equipment. This was visible at the injection point, which was black at the beginning of the trial and looked like new concrete by the end of the 3-week trial. Protection of equipment could save a municipality several hundred thousand dollars. Prevention of hydrogen sulfide in the collection system can also prevent crowning.
Sludge reduction was noticed during this treatment. Normally the City wastes sludge every 10 days. Sludge was not wasted once during the testing phase. We do know from previous tests with EM-1® that sludge reduction as high as 50% can be expected with regular applications.
An Experiment Using EM Treatment Methods To Treat Raw Sewage
In Naha city of Okinawa prefecture in Japan, approximately 1,800 tons per month (475,200 gal) of fresh waste and accumulated sludge from treatment tanks are vacuumed up to trucks to be transported to a temporary storage and eventually shipped out to open sea to be dumped. Since the signing of the London Agreement and other treaties on protection of oceanic environment force waste treatment completed on land.
In this experiment, an experimental plant was set up to evaluate effectiveness of Effective Microorganisms® (EM®) in waste treatment and to apply the results to the waste treatment plan of Naha city.
1) To set up an experimental plant in a relay facility to evaluate effectiveness of EM in waste treatment.
2) To design an experimental plant, instruct its construction, carry out the experiment, and evaluate the results.
EXPERIMENTAL METHOD (Follow-up experiment)
Experimental Period: April 27 - November 30, 1996
Experimental Site: Urasoe-city in Okinawa prefecture in Japan.
Experimental Plant: See the attached chart.
Experimental Subject: Fresh waste which are trucked in.
Water Quality (general)
pH, BOD, COD, SS, total nitrogen, total phosphate, colifoms count, color, clarity.
Water Quality (other)
Cadmium, lead, hexa chromium, whole chromium, arsenic, alkylate mercury compound, whole mercury, cyanogen compound, organic phosphate compound, polychlorinated biphenyl (PCB), phenol, fluorine compound, soluble iron, soluble manganese, copper, zinc, N-hexane
extract, trichloroethylene, tetrachloroethylene.
Hydrogen sulfide. methyl mercaptan, methyl sulfide, dimethyl sulfide.
Points of management and operation.
Activated EM-1® and other types of EM® materials were placed in a receiving tank and a screening tank as needed. Theoretically, 1-2 litters of extended EM® per 1 ton of waste is recommended. (How to Activate EM-1® is explained later in this paper.)
EM (manufactured by Sankou Sangyou)
MSK101 (predominantly lactic acid bacteria and yeast)
MSK102 (predominantly enzyme)
MSK103 (predominantly photosynthetic bacteria)
EM-X (manufactured by Tropical Resource Plant Research Organization)
EM-X ceramics (manufacture by Amron)
Molasses (manufactured by Sankou Sangyou)
As seed sludge, 1.5 tons of treated sludge from other treatment facility in Okinawa prefecture was introduced and trained for 2 months to adjust to fresh waste, which was used as the control group.
The experimental plant was remodeled to resolve such problems encountered in the first experiment as in the areas of screening, anaerobic treatment, and retention time to compare treatment effectiveness prior and after the remodeling.
Fresh waste was selected over accumulated sludge as experimental subject because fresh waste is more difficult to treat. Sludge is constituted predominantly of fibrous material which are easily removed prior to treatment, and the general quality of sludge is better (lower BOD,
COD, SS, nitrogen, and phosphate) than that of fresh waste.
One litter of extended EM mixture specially blended for waste treatment was added to 1 ton of waste. The discharge water was returned to a temporary holding pool of a relay facility. The facility operation was set up as follows to evaluate EM effect: (Note: Received waste was diluted to the extent which makes easy for microorganisms to work, prior to be forwarded into aeration tank. The discharge water is not diluted.)
April 28 - June 14
Start up operation for active sludge method.
Average treatment volume was 300 litters/day including non-diluted waste (average ratio of fresh waste to water was one to 4-5).
Mixed liquid suspended solid (MLSS) in aeration tanks was set to 6,000-9,000 ppm.
Average aeration time for the first aeration tank was set to 24 hours, and the second
aeration tank also to 24 hours.
Retention time (from holding tank to discharge, provided that the diluted waste is 1.5 cubic meter) was 10-12 days.
June 14-July 14
Start up operation with EM application, other conditions being the same as described in above l.
July 15-August 31
Operation with EM application with additional load.
Average treatment volume was 500 litters/day including non-diluted waste (average ratio of fresh waste to water was one to 1-2).
MLSS was set to 13,000-16,000 ppm in aeration tanks.
Average aeration time in the first aeration tank was set to 20 hours (max. 22 hours; min. 14 hours), and the second aeration tank to 16 hours (max. 20 hours: min. 2 hours).
Retention time (from holding tank to discharge, provided that diluted waste is 1.0 cubic
meter) was 15-16 days.
Standard active sludge operation (waste water is diluted by tap water and treated water).
Average volume of treated waste was 600 liters/day (average ratio of waste, tap water, discharge water was one, one, 4).
MLSS in aeration tanks was set to 6,000-9,000 ppm.
Average aeration time in the first aeration tank was set to 12 hours (max. 14 hours; min. 8 hours), and the second aeration tank to 16 hours (max.20 hours; min. 12 hours).
Retention time (from holding tank to discharge, provided that diluted waste is 3.0 cubic;
meter) was 5-6 days.
Volume of the total treated waste during the period
The total treated volume during the period amounted to 83 cubic meter. Miscellaneous floating materials were not removed from waste after August 22, and the received waste as a whole was forwarded to holding tank. Surplus sludge was stored in a sludge condensation tank, and its supernatant liquid was returned to holding tank.
See attached Chart-1.
See attached Chart-1.
Surplus sludge generated during the experiment in order to control MLSS in aeration tanks was temporary stored in a sludge condensation tank to be returned to holding tank as needed. Therefore, removal of surplus sludge for the purpose of cleaning the condensation tank was never made.
Treatment Capacity of the Plant
The experimental plant was designed to treat the waste of 143 persons, and as such, a standard design sets BOD bad to 1.86kg/day. However, in this experiment, the actual BOD load was 6.0kg on the average against the total capacity. Against the aeration tanks, the load was 1.9 times of the standard: 2-3 times overall. In spite of such strenuous condition, BOD was maintained well below the standard value of 5ppm, which indicates that the experimental plant is capable of treating twice the volume it was designed for.
Cost of EM and EM Related materials
The total amount of Activated EM-1® applied was 90 litters et JPY 12,150.
EM#2 (MSK102) used at the time of bulking was JPY 20,000.
EM-X ceramics was JPY 30,000.
Other EM related materials amounted to JPY 62,150.
Running cost per 1 ton of fresh waste was JPY146.40 (for Activated EM-1®).
The cost for EM in this experiment is not low compared to ether experiments: such as. JPY 500.000/year at Shimodakawa Clean Center which treats 60 cubic meter or JPY 100,000 at Kaya city. It becomes less expensive as EM applied continuously over longer period.
Use of Electricity
Average aeration time before EM application was 24 hours for both the first and the second aeration tanks. Three months after EM application, the time was reduced to 12 hours for the first tank and 16 hour for the second tank, and electricity use was reduced by 41%. In aerobic treatment system such as active sludge method, most of electricity cost is for aeration. The experiment proved that electricity use can be reduced by 41%. It is not reasonable to assume that the same applies to all facilities because of difference in their operation environment, but it will serve as a guideline.
Use of Water
Because of the use of discharge water to dilute fresh waste, amount of tap water or ground water which are otherwise used for dilution was reduced. Accordingly, water bill was reduced. Requirement of ground water to build a treatment facility had limited feasible site for a treatment facility. However, EM application made such requirement unnecessary.
In this experiment, EM was applied to treat highly loaded fresh waste in a traditional multipurpose facility (capacity for 143 persons; where ceramics were used as contact material). Generally speaking, a multipurpose treatment facility is designed to treat waste & water of BOD 200-250ppm; therefore, it is inadequate to treat fresh waste of BOD over 1,000ppm. However, in this experiment. such inadequate facility was used to prove EM effect.
The results are as follows:
1. Good discharge water level of BOD 5ppm was achieved without using chemical agents and in a low function level facility. EM has proved to be an effective biological agent in waste treatment system.
2. Chemical agents which are required in the current ordinary treatment system to remove nitrogen and to maintain lower coliform count, were not needed. Application of EM alone achieved the same effects.
3. Generation of surplus sludge was far less than initially designed, and use of electricity was reduced by 41%. Running cost has been drastically reduced.
4. It seems reasonable to assume that removal of total phosphate and desired COD level will be achieved by increasing the amount of discharge water to be returned to dilute fresh waste.
5. Foul odor was eliminated, which created healthier and more comfortable environment for the facility employees and the surrounding area residents.
6. To Be Studied Further
How to control total phosphate and COD level.
How to control amount of sludge more precisely.
Design a plant to control phosphate, COD, and sludge.
In order to reduce cost, EM® is recommended to be Activated, or grown. EM-1® is used as seed.
EXTENDED EM-1® FOR WATER TREATMENT
Basically the same as regular extended EM® which uses molasses as feed to cultivate EM®. For water treatment use, however, the untreated (waste) water is added in addition to molasses to facilitate easy transition of feed from molasses to untreated waste. Ways of extension differ depending on density and type of load. EM® treated water is also added to facilitate extension. (Waste water may include feces, urine, laundry discharge water, factory discharge water. The amount of EM-1® to be used and the way of extension may need to be adjusted.)
How to Activate EM-1®
EM-1®, molasses, water (untreated water, pond water), Tank (air-tight container) Heater, thermostat (to maintain liquid temperature warm)
Materials are mixed to meet the type and density of bad of the subject water to be treated and kept in an air-tight container for the minimum of 2 weeks, maintaining liquid temperature over 20 centigrade. See below for general guideline for type and density of load. Addition of 0.1% of EM-X may help to facilitate activation process.
BOD Level and EM-1® Activation
mg/litter (ppm) except for pH, coliform count (#/ml), clarity, color.
Discharge requirement is in accordance with the capital order (No.35 in 1970). “Discharge Standard for Toxic Material” and “Discharge Standard in General”, and additional discharge water requirements for Naha water area in Okinawa prefecture.
Blanket Pre-Treatment: An Innovative Solution to Some
Cr Julie Boyd
Mackay City Council
This paper reports on the successful trials of an innovative method of dealing with significant odour and other environmental issues encountered by a Local Government Authority. Trials first began in 1998 when the City Council was faced with widespread community concern over sewerage odours. Combined with escalating costs for upgrades and on-going maintenance to its sewerage collection and treatment facilities, these presented a real challenge to the Council.
System-wide incubation and inoculation techniques developed in Queensland and use of EM® (Effective Microorganisms®) with assistance from Professor T. Higa and EM Research Organization (EMRO) in Japan were major inputs.
Some important aspects of this unique approach include (a) methods of inoculation resulting in a much lower than expected rate of microbiological augmentation, (b) a system-wide approach rather than focus on trouble spots and (c) an accumulative inoculation pattern.
Introduction Mackay City
Mackay, a city in Queensland of some seventy thousand people, boasts a per capita income in Australia second only to Canberra, the national Capital. The population growth rate in Mackay in the last few years has been one of the highest in the nation. This has put considerable strain on the city’s sewerage system and treatment facilities.
Until recently the region’s economy has been based on sugar and coal, but development to take advantage of the huge tourism potential is now well established. Combined with a tropical climate and monsoonal weather patterns, this can equate to significant seasonal fluctuations in effluent flow and consequent problems in the handling of effluent.
The city sits across a tidal river 330 km north of the Tropic of Capricorn, and the geology is based on eons of silt and sedimentation. There are areas of natural wetlands that add to problems of drainage and flow and constitute a flood threat. The area also experiences huge tidal rises and falls and these can influence drainage and discharge of effluent.
In addition, Mackay acts as a major gateway to the World Heritage listed Great Barrier Reef Marine Park. In recent years Regional and National Authorities have focussed considerable attention on the effects of sewerage effluent on the Barrier Reef. Corals are particularly sensitive to higher than normal nutrient loads and consequently, Mackay City Council has been investigating many avenues which aim at higher quality of effluent and reduced risks for the environment.
Due to increased load on the sewerage system in recent years Mackay has experienced a growing problem with sewerage odor. This has resulted in a concerted and very public attempt to find a community-wide solution. The odor problem is centered on effluent arriving at the city’s main Sewerage Treatment Facility and at each of the main Pumping Stations across the region.
A series of previous trials were undertaken over a period of three years using chemical and organic additives, physical structures, filters and other processes to try and alleviate the odor problem without success.
Pre-Treatment as a Concept
There has been little change in the practices of waste treatment in Mackay (as in many cities across the world) since the disappearance of night carts that were used to carry away domestic refuse in the late eighteen hundreds. That idea gave way to an installed system of buried pipework. The conventional method of treating sewerage is by transferring effluent through a network of sewerage mains and pumping stations to a sewerage treatment plant at or close to the site where the treated effluent will be released. This is true in Mackay, where effluent is discharged to waters directly behind the Great Barrier Reef after treatment.
As the sewerage passes through the mains and pumping stations, the effluent becomes an incubating culture with the production of a variety of fermentation products including hydrogen sulphide and ammonia. The production and release of hydrogen sulphide particularly, and other undesirable substances in and from effluent can be related to flow rates and detention (Holder and Hanser, 1986). The composition of the sewerage effluent is continuously changing during its passage and is significantly effected by the action of micro-organisms which are present in large numbers in cultures attached to the walls of pipes and other structures over which it passes.
The resulting mixture of material is consequentially accompanied by aggressive atmospheres which continually damage the pipes, pumping and other equipment. In Mackay, as in many other cities, intermittent flow rates, long retention times in the system and a relatively old piping network combine to allow production of large quantities of hydrogen sulphide throughout the entire system.
After various unsuccessful attempts at suppression of odours, it was proposed that an attempt be made using “EM” formulations produced by EM Research Organization (EMRO) and techniques pioneered by Vital Resource Management Pty. Ltd., (VRM) to attack the problem at its source. This involved setting up a series of low dose, widespread, accumulative inoculation points at which EM formulations are injected. A pattern of inoculation was established such that all effluent in the system if inoculated at least once well before reaching the sewerage treatment plant (VRM, 1999).
The initial intention of this blanket pre-treatment program was to promote the development of a partially self-sustaining culture of competitive micro-organisms throughout the collection network which would reduce the production and release of hydrogen sulphide (Bellamy, 1998). As these new cultures became established, it was proposed that inoculation be continued at a level which would promote a change in the overall process of putrefaction of waste and allow a partial breakdown of organic material in the waste without the usual negative by-products (Higa and Chimen, 1998).
The pre-treatment process makes use of the alternation between anaerobic and aerobic conditions which occurs in a piping network to begin some of the processes otherwise reserved for the treatment plant (Bellemy, 1998). One of the traditional methods of combating the negative impacts of hydrogen sulphide has been the injection of oxygen to long rising mains. However, the cost of this has become increasingly difficult for Councils to support. An alternative method was thus also sought for addressing the effects of hydrogen sulphide in long rising mains.
Initial trials focused on an area of Mackay’s sewerage system known as and the Beaconsfied collection system which collects on average
Methods approximately 2.4 megalitres of mixed effluent per day. Severe odour problems along this system had resulted in a series of complaints and the formation of a resident’s action group. Real Estate values in the immediate vicinity of the main collection station had been dramatically reduced due to the continuous and invasive sewerage odour experienced within approximately one kilometer of the station over many years. Thirteen inoculation points were selected and equipment installed at each included a specially constructed storage and equipment cabinet and metered dosing equipment capable of continuous inoculation at rates as low as 100 ml per hour.
Extended EM formulation were prepared and diluted at four parts to one with aged (de-chlorinated) water. The resulting mixture was delivered in an even amount to each inoculation site such that a total inoculation of approximately 100 ppm inoculum to waste flow was achieved across the system.
Dosing began on 29 March 1998. After one month, dosing rates were reduced to approximately 25 ppm and thereafter, were progressively reduced to a low of approximately 1.5 ppm. In February 1999, dosing rates were increased to approximately 15 ppm in an attempt to address indicators other than hydrogen sulphide. After a period of one month the inoculation rate was reduced again to 2.5 ppm and continues at that level to date.
In July 1998 the trail was extended to include a second section of the system known as the Slade Point collection system. A further ten inoculation sites were chosen and similar equipment installed. Dosing began on 15 July 1998. Inoculation sites take two forms : (a) Injection above the influent stream at an existing pumping station; (b) Injection to a specially constructed inline biological filter (VRM, 1999). Injection is by way of specially designed nozzles which allow partial aerosoling of liquid and a simultaneous full cone droplet spray.
Installation of the spray nozzle is done so as to achieve both a mixture of EM with all effluent in the situation and mist of droplets floating in the ullage space provided above the effluent. Biological filters contain a quantity of EMX ceramic media which is placed so that effluent passes over and through the ceramic. Inoculation was continued on a 24 hour per day basis and cannister refills were completed on a 10 day rotation.
Sampling points were nominated throughout the area and a routine of data collection was established to allow sampling across a wide range of effluent conditions, flow rates and weather conditions. Community monitors were also selected and interviewed periodically for anecdotal progress information.
The immediate and most notable result of the process was that all detectable sewerage odour normally generated from the system ceased within 24 hours of commencement of inoculation. Anecdotal reports from residents, Council staff and trial monitors confirmed that odours were suppressed both inside structures and in the surrounding areas. This effect was consistent at initial injection to both discrete systems trialed. This was supported by an immediate drop in water-borne hydrogen sulphide readings to a steady reported level of less than one mg/l.
Early in the trial, community monitors reported the appearance of a different odour. This was identified as being odour generated by the EM itself (a sweet fermentation odour). As dosing rates were decreased this odour diminished and is now not detectable.
When inoculation rates dropped below 2.0 ppm, odour was detectable inside the sewerage structures at some points. It was notable that where odours were discovered, new additions to the system had been completed which were collecting effluent not previously inoculated. Fat build-ups which normally plague most local authority sewerage systems where observed to be significantly reduced. This resulted in much reduced costs for labour in periodic cleaning/removal of fats. It has been noted that fats do not reconstitute downstream of inoculation points and that build-up of fats does not re-occur once cultures of EM are observable in the sewerage system. Any residues are easily hosed from the walls of structures and do not subsequently require mechanical scraping or other removal techniques.
Replacement of Oxygen Injection
A specific trial was conducted to ascertain the effectiveness of using biological processes promoted by EM to replace direct oxygen injection into large rising mains. These trials concluded that where blanket pretreatment has occurred, the level of DO present in effluent at the end of long rising mains was at least equivalent to that present where direct oxygen injection was undertaken.
Following these trials, the Mackay City Council ceased oxygen injection to all areas where blanket pre-treatment is occurring. On-going sampling shows that hydrogen sulphide levels in effluent at the end of long mains is consistently lower with Blanket Pre-Treatment than with oxygen injection.
Containment of a Major Spill
A major sewerage spill occurred on the Slade Point section of the system during the trial period when a contractor ruptured the main transfer line prior to the treatment plant. At the time, even though approximately 6.5 mega litres of raw effluent escaped and lay adjacent to main roads and residential areas for several days, not one complaint of odour was received.
Council received positive responses from both community and EPA representatives even though no additional remedial work was undertaken other than to repair the rupture.
The nature of the area provided an excellent opportunity to observe the overall quality of effluent arriving at a point just prior to the treatment plant and the potential positive impacts of increased cultures of beneficial micro-organisms in the pre-treatment phase.
Rupture occurred on 8th April 1999. Works to repair the rupture were completed 14 April 1999. In the interim effluent sat in bright sunshine in shallow sheets covering a large area known as a habitat for bird life. Progress was closely monitored by Council, members of the community and EPA and Health Department delegates. To date no remedial work has been required and no negative environmental impacts have been recorded.
Overall Trend Indicators
Over a 12 month period, Council recorded gradual improvement in all leading indicators of effluent quality in samples taken from the end of the collection and transfer lines in the trial area. At inception of the trial, it was postulated that inoculation over a period of 6 to 12 months would see beneficial micro-organic cultures gradually become resident in the collection network. Hence it was expected that sustained improvements in water quality indicators would begin to appear gradually over a similar period. This effect was borne out by data collected over a twelve month period. In February, 1999 an attempt was made to speed up this process by increasing the rate of inoculation for a period of one month.
Discussion It is concluded that by fostering a partially self-sustaining culture of beneficial micro-organisms throughout the sewerage system, it is possible to address at least some of the problems which typically make sewerage collection and transfer difficult and costly.
By combining innovative inoculation techniques developed by VRM with some of the known characteristics of EM formulations, it was possible for Mackay City Council to institute a system wide solution to some long established problems.
Addressing odour problems by promoting beneficial anaerobic activity to compete with and overcome processes which produce odorous substances has allowed the Council to address the cause rather than the symptom of a challenging problem.
At the same time, subsequent effects such as savings in maintenance time and material costs and a saving in the costs of direct oxygen injection emerge as significant benefits for the Council. A significant subsidiary benefit is the reduction of environmental risks associated with accidental spills by having beneficial micro-organic activity already in progress in the collection phase of the system.
As the program continues, it is anticipated that further benefits in terms of reduced augmentation costs at the Sewerage Treatment Plant will arise from the ability to deliver at least partially treated effluent from the collection system itself.
As a result of the considerable success of the program so far, Mackay City Council has committed to the installation of a program covering all effluent in the city and surrounding areas.
Bellamy, K. 1998. Method of Treating Waste Water, VRM Enterprises Pty Ltd.
Higa T. and N. Chinen. 1998. EM Treatment of Odor, Waste Water and Environmental Problems
VRM. 1999. Method of Treating Waste Water, VRM Enterprises Pty Ltd, 1999.
MCC. Data Collection and Water Analysis by Mackay City Council Laboratory
MCC and CASCO. Data Collection by Mackay City Council, EPA Queensland and VRM; Analysis by CASCO Laboratories, Mackay Qld.
Holder, G.A. and J. Hauser. 1986. Influence of Flow Velocity on Sulfide Production Within Filled Sewers, 1986.
Preliminary Experiment of EM Technology on Waste Water Treatment
Gede Ngurah Wididana
Indonesian Kyusei Nature Farming Society, Indonesia
The objective of the experiment was to investigate the effect of EM4 on improving the quality of waste water. The experiment was conducted in two locations of candy factory, viz Nestle and Trebor Companies in Jakarta. The EM4 was treated in laboratory condition to the effluent of waste water of non adjusted pH (pH 4.0) and adjusted pH (pH 7.44) in concentration of 1mL/L of waste water. During 11 days after treatment, the chemical oxygen demand(COD) of waste water was decreased by 31%, 80%, and 76% for the treatment of control, non adjusted pH and adjusted pH of waste water respectively. The EM4 treatment in the aeration tank was also conducted in order to know about the continuous application of EM4. The EM4 treatment was applied periodically every 10 days. The data of (COD), biological oxygen demand (BOD), suspended solid (SS) and pH of the waste water were collected daily until 40 days. The treatment of EM4 tend to decrease COD, BOD and SS but did not affect the pH of waste water. The COD, BOD and SS increased 11 days after EM4 treatment.
Improper management of industrial waste water can create some environmental problems, because it contain large amount of carbohydrate, protein, fat, mineral salt and chemical compounds. The content of high organic matter in the waste water can be used as a source of energy for the growth of microorganisms (Betty and Winiarti, 1991). The lack of diluted oxygen in the waste water due to the high content of organic matter can create malodor and muddy water. High content of protein, sulphur and phosphate will result in the formation of hydrogen sulphide which can cause malodor and make the surrounding building black. Most of the malodor arises from the degradation of nitrogen, sulphur, phosphate, protein and organic matter in the waste water.
The high content of biological oxygen demand (BOD) and chemical oxygen demand (COD) in the effluent of waste water is very strongly caused by water pollution. The water pollution is responsible for the disturbance of ecological balance in the waste water that can cause death of fish and other biotic component of water. The high content of nitrogen and phosphate in the effluent of waste water also create muddy water and high sedimentation. Rapid growth of algae create malodor because of the decaying of dead algae and anaerobic condition in the waste water that consequently cause death of fish and other biotic component of water (Ronald and Richard, 1981). In general, the industrial waste water management consist of physical, chemical and biological management. It was combined together in order to achieve a high quality of waste water effluent.
Especially for the biological management, microorganisms (algae, bacteria, protozoa) is utilized to degrade the organic compounds of waste water to be simple organic compounds (Ronald and Richard, 1981). EM4 is a mix culture of microorganisms consisted of Lactobacillus, lactic acid producing bacteria, yeast and fungi that have the potential to increase the biological reaction for the management of industrial waste water (Higa 1994a). The objective of this experiment is to investigate the effect of EM4 on increasing waste water quality.
Materials and Methods
This experiment was conducted in collaboration with the candy factory of Nestle Company, located in Jakarta, during September 1994 to October 1994. Two liters of waste water collected from the effluent was filled into a glass beaker. The pH of the waste water were measured. Each treatment was aerated by blowing oxygen to the waste water with blower equipment. Data of the experiment was established as follows:
This experiment was conducted in collaboration with the candy factory of Trebor Company, located in Jakarta during September to October 1994. EM4 was applied in the amount of 50 mL to the aeration tank of 84 m3 in size or in the concentration of 0.57 mL/L of waste water. Furthermore the EM4 treatment in the same dosage was applied periodically every 10 days. Data of the suspended solid (SS), chemical oxygen demand (COD), biological oxygen demand (BOD) and pH of waste water was collected after management in Trebor Company and aeration tank are shown in Fig. 1 and 2.
Figure 1. Scheme of waste water management
Figure 2. Aeration tank
Results and Discussion
The experiment 1 showed that the inoculation of EM4 to the waste water both on the adjusted pH (pH 4.0) and non adjusted pH (pH 7.44) tend to decrease COD. During 11 days after treatment, the treatment of EM4 decreased COD of the waste water from 7,250 ppm to 1,430ppm (80.3% reduction) and from 7,250 ppm to 1,740 ppm (76% reduction) for the non adjusted pH and adjusted pH of waste water respectively. On the other hand the control treatment showed various change of COD concentration. In the first and sixth day after treatments, the COD concentration of the control tend to increase while on other days, it tends to decrease. At 11 days after treatment the COD of the control treatment changed from 7,250ppm to 5,000 ppm (31% reduction). The adjustment of pH in the waste water could not affect the action of EM4 on decreasing of COD. See Fig. 3.
Figure 3. Effect of EM treatment on the reduction of COD
The fermentation of organic compounds in the waste water conducted by EM4 decrease COD gradually. It means that the biochemical reaction in EM4 treated-waste water is increasing due to the higher concentration of oxygen in the waste water than those in control.
Chemoheterotrophic and photosynthetic bacteria have important role for the waste water management to degrade each organic compounds. They also oxidize NH3 and uses sunlight as source of energy and CO2 as source of carbon. The mix culture of microorganisms is more effective to degrade various compound than those of single culture of microorganisms due to the complex of organic and inorganic compounds in this waste water (Betty and Winiarti, 1990).
Experiment 2 showed the EM4 treatment affecting COD, BOD and SS but not the pH of waste water (Fig. 4 and Fig. 5). During first to ten days after treatment of EM4 the COD, BOD and SS decreased to 40%-55%, 42%-55% and 44%-71% respectively. Continuous application of EM4 every 10 days showed decreasing concentrations of COD, BOD and SS. The action of EM4 to degrade the organic compounds in waste water was proposed by Higa (1994a), who reported that EM4 was applied successfully for the recycling of organic compounds of sewage and kitchen garbage. The result of fermentation by microbes was the formation of simpler organic compounds, such as amino acids, alcohol, sugars, organic acids and ester. It was also assumed that the fermentation process released active oxygen diluted in the waste water that consequently activate the biochemical reaction (Higa, 1994 b).
Organic compound consisting of carbon, hydrogen, and oxygen with additive element of nitrogen, sulphur, phosphate, etc. tend to absorb oxygen. The available oxygen in the waste water is consumed by the microorganisms to degrade organic compounds. Finally the oxygen concentration in the waste water decreases, indicated by increases in COD, BOD, SS, and the waste water also became muddy and releases foul odor. The higher concentration of COD indicates that the high content of organic compound could not be degraded biologically. The treatment of EM4 after 10 days in the aeration tank should be continued due to the increase in COD concentration. This phenomenon indicated that the EM4 cannot exist well in the condition of this waste water, because of the strong pollution and the low number of microorganisms in the waste water.
Figure 4. Effect of treatment on the reduction of COD, BOD, SS and pH
Figure 5. Effect of continued EM treatment on the reduction of COD, BOD, SS and pH
1. Adjustment of pH of waste water is not required before EM4 treatment.
2. EM4 do not affect the pH of waste water.
3. The treatment of EM4 decreases COD, BOD and SS of the waster water.
4. The treatment of EM4 on decreasing COD was more effective then those of control.
5. Continuous application of EM4 was needed due to the low number of microorganisms in waste water and continuous pollution from the waste water.
Betty, S.L. and Winiarti, P.R (1990). Penanganan Limbah Industri Pangan. Kanisius, Yogyakarta. 148 p.
Ronald, M.A. and Richard, B. (1981). Microbial Ecology, Fundamental and application.
Addison-Wesley Publishing Company. Sydney. 560 p.
Higa, T (1994 a). Personal Communication. EM Technology Serving The Wold. 7 p.
Higa, T (1994 b). Personal Communication. Producing Safe Foodstuffs. 16 p.
Ming Yang Project: Treatment of Discharge Water From Starch Production Factory in
People’s Republic of China
Reporter: Kouichiro Shiba
Report Date: February 25, 1997
A national starch processing factory at Kwang si Chowang Administration Area in People’s Repubic of China
Ming Yang factory, selected as an experimental factory, is located in a poor south-western mountainous area of Republic of China. To facilitate economic development in this area, starch processing and sugar processing factories were introduced. They are now the leading industries in the area. The factories in this area were started without assessing their environmental impact, and discharge water from over 200 factories currently in operation have polluted environment. More than half of the factories have received warning to dose down the factory operation. But dosing down, if enforced, would create major economic set-back for the area residents, leaving no receptor of the area farm products and increased unemployment.
Water Treatment in China
Generally speaking, discharge water is ether left without any treatment or pooled in a pond for natural oxidation in China. Since natural oxidation takes long time to purify water, ponds serve primarily as holding tanks in order net to spread pollution. When discharge water becomes large in quantity such as 10,000 ton per day as in the experimental factory, no pond can handle such volume. As a result, excess water is spilled to rivers and takes without being treated.
In the days when ponds received water discharged only from domestic households, pond water had been maintained in balance. Organic matters in such discharge water were just enough to feed pond fish. But, large amount of discharge water primarily from factories sets the balance off, generating four odor. In addition, discharge water from starch processing and sugar processing factories are rich enough to be processed again to produce alcohol.
Discharge water from alcohol production sometimes measures up to 100,000ppm and is extremely difficult to purify. No report has been made yet that successfully treated discharge water from alcohol production, except EM treatment.
Active sludge method which is generally recognized as effective and stable, could not successfully treat discharge water from alcohol production. In this experiment, application of EM is expected to treat successfully water discharged from alcohol production and pooled in ponds.
Synopsis of the Experiment
In January 1995, with support of International Nature Farming Research Center, tow local residents who had been actively promoting EM launched on the experiment. They selected one (pond #1; then 50,000 ton and 25,000 ton now) of the oxidation ponds of the experimental factory because excess pond water is spilled out and polluted a dam which supplies drinking water to Nan Ning city. Another reason is that the experiment would serve as a demonstration to motivate more than 10,000 people who live in the former national farm where the factory is located.
The experimental application of EM eliminated foul odor and lowered BOD from 3,000ppm to 1,400ppm in the first three month period. Based on this result, EM Research Organization opened an office in China, and expanded the experiment to treat alt 10,000 ton per day discharge water with EM.
Condition Prior to the Experiment
The former national farm covers a large area; it takes 10 minutes by car from the entrance to its office and 15 more minutes from the office to the treatment ponds. When I first visited the factory, foul odor was detected far from the factory and so bad by the ponds that gave me a headache. In a 36,000 ton oxidation pond, the water was almost black and seeping out through its dike.
Three different types of discharge water (see Chart-1: Discharge Water From Processing) flows into the treatment ponds, and the mixture of the three measures BOD 9,000ppm, COD 40,000ppm, pH 4.0.
Extended EM and its Application
The water discharged from alcohol production is used as base material to extend EM, following an example in Brazil. Aeration is impossible because of high cost due to vastness and heavy pollution. The amount of EM applied is set a little over 1%, i.e., approximately 10.8 ton of extended EM to 10,000 ton of discharge water per day. The extended EM of 10.8 ton is poured from 5 different places every day. The distance from the factory to the ponds is quite long, and the condition differ very much from one point to another. Therefore, the following factors were considered in selecting five points to place a tank for extending EM and pouring the extended EM into discharge water.
The water discharged from alcohol production is very hot. Even after it is mixed with ether types of discharge water, it is well over 60 Celsius. The first factor for selection is that the temperature is below 50 Celsius.
The second factor is that further the distance from the ponds is better. Because it gives EM time and place to work. The third factor is strong foul odor. Stronger the odor, more active the putrescent bacteria are, and earlier treatment is required.
Preparation started in the end of 1995, and the experiment started in January 1996. Three major developments were as follows:
Because the ponds are lined with soil, applied EM increase buffer function of soil lining and facilitate cleaning effects. The water discharged from alcohol production is highly polluted, but serves as good substrate for EM. In other words, based on the belief that discharge water is a good material to extend EM, the beet way to extend EM in the ponds was looked into. In addition to application of EM, Bokashi was inoculated to the bottom of three ponds (15,000 ton each) established for oxidation and sedimentation, and coal crumbs were placed to serve as bed to cultivate EM (in place of ceramics).
Our trust in EM was net always firm when no changes were observed. The discharge water, although it was considered good for extending EM, took time to resolve protein. The discharge water from alcohol production was polluted beyond imagination, and pH of the discharge water stayed below pH5 which means that photosynthetic bacteria cannot be active. Aeration was a tempting alternative to raise pH level, but it is too costly to be adopted as a standard procedure. A mixing screw and a pump were used as an alternative to aeration, but they made only a little difference.
In July 1996, we realized that Mr. Inatomi of EM Research Organization hit the head of the nail when he said that let the nature take care of it. A mixing screw and a pump were nothing next to the natural aeration of wind and rain. Nature has the power, and EM draws the best out of nature, and we only help EM. We discarded minor manipulation. Around this time, #1 oxidation pond (25,000 ton) which had been under the experiment for two years, changed its color from creamy white to black, and bacteria became activated. In the black water, black coagulated material started floating and eventually sank to the bottom.
The discharge water suddenly became clean, and BOD decreased down to 191 ppm in two month period. The largest pond which is the final deposit pond, started to be clean while the factory was in recess (2-3 month recess happens due to seasonal material supply). Although the factory resumed its operation in November 1996, both BOD and COD of the final deposit pond keep decreasing. (See Chart-III).
The sediment et the discharge water of alcohol production is used as fertilizer in orchard, and the water from the final deposit pond is used to make bricks which are to be baked soon. The dried bricks showed smoother surface and less cracks.
The 36,000 ton oxidation pond described in “Condition Prior to the Treatment” turned into a beautiful green grass field. This pond is located by 5 sedimentation ponds and was ordered by the area environmental office net to use. The factory brought in a machine to separate solid matters out of alcohol discharge water in this year. Until the last year, the solid matters accumulated in oxidation ponds and made the ponds shallow and useless; thereby, necessitating to remove the accumulated matters and dump to the said oxidation pond to its full. Because of evaporation and restored natural power of the soil, the matters dried up and turned into good soil to nurture grass. The farmers in the area recognized the richness of the soil and took it all out to their farms. In order to increase effectiveness, a pump was placed to feed #3 pond water back to the oxidation pond in January 1997. (See water flow chart-ll ).
The experiment is not completed, but has been successful to this point with cooperation of many who are concerned with the environment and the community.
Chart-1: Discharge From Processing
Wash with water
Discharge water #1
Discharge water #2
Soak & Separate
Fermentation & evaporation
Discharge water #3
Discharge water #1
= Approximately 1,000 ton per day; includes hydro-cyanic add.
Discharge water #2
= Approximately 5,500 ton per day; includes large molecule protein and fiber; BOD
Discharge water #3
= Approximately 3,000 ton per day; BOD 40.000ppm, COD 80,000ppm.
Chart-II: Ming Yang Starch Processing Factory.
Chart-III: BOD & COD Measurement of the Final Deposit Pond.
Options for Advanced On-Site Treatment
K. M. Bellamy1 and Brian Horsley2
Vital Resource Management Pty Ltd, P.O. Box 350 Deeragun Qld 4818 Australia
Vital Resource Management Pty Ltd, 122 Parkdale Dve Leslievale Tas Australia
Identification of specific elements of a process stream and the ability to purchase elements either as a package or individually offers end-users flexibility and encourages understanding of the processes by those who have to use them. Incorporation of EM® (Effective Micro-organisms®) based, low-energy, low-technology elements has allowed clients in sensitive areas to tailor a “modular process stream” which best suits their site and which allows meeting of the highest standards for effluent treatment and re-use. Incorporation of microbial balancing by regular inoculation enables the systems to cope with the serious problems of fluctuating loads and odour generation. A simplified process stream approach allows minimal maintenance on remote sites and multiple failsafe mechanisms including advanced oxidation to allow the process to produce high levels of effluent quality in extreme circumstances.
There are currently twenty-six Government approved on-site treatment packages available in Australia to developers. Distinguishing the benefits and disadvantages of these prepackaged options is often clouded by proprietary focus or a lack of prior experience on the part of the environmental license holder or land developer. Mechanically intensive operations and concurrent maintenance issues make most of these unsuitable for sensitive and remote sites.
Australian Environmental Protection Act provisions regarding waste water have been significantly tightened in the past ten years. An example of this is found in sites within the Great Barrier Reef Marine Park area where all EPA License renewals since 1998 include a provision for nil discharge to waters. In addition, incorporation of AS,NZS 1547-2000 (On Site Sewerage Treatment) and an upgrade of Water and Sewerage Acts has seen a renewed focus on water quality outcomes and suitability of a given process for a given site. Inclusion in Australian Standards of design criteria for a range of discharge methods has also fostered a willingness to explore advanced treatment outcomes which do not focus entirely on mechanical processes.
Two prominent factors influence treatment of waste water in sensitive sites in Australia: the tyranny of distance and seasonal fluctuations in population. Distance has traditionally played a major role in system failure as maintenance presents a difficult and expensive proposition and is often overlooked as a result. Seasonal variations in occupancy have an extremely deleterious effect on operation of aerated waste water treatment plants.
It is not unusual for a system to experience nil to 10% load for several weeks followed by maximum capacity for several days. Maintenance of biomass using traditional activated sludge or batch reactor processes can be nigh impossible under these conditions.
These factors make a biologically balanced approach such as that offered by an integrated augmentation program using EM® and a low maintenance system design increasingly attractive options.
Materials and Methods
The Modular Process Stream offered consists four basic “Elements” which are each contained in discrete chambers (tanks) and sized and sited appropriate to the requirements of the particular operation. A brief description of these elements is included below. Typically, each system incorporates an augmentation phase where EM® is added to collected effluent, a sedimentation phase where fermentation and rapid settlement of solids is promoted, an aeration phase where both intermittent and constant aeration are used to promote growth of cultures and an advanced oxidation phase where rapid disinfection and final BOD removal is completed.
Figure 1. Modular Process Stream - Collection and Inoculation Phase
Figure 2. Modular Process Stream - Sedimentation and Aeration Phases
Figure 3. Modular Process Stream - Advanced Oxidation Phase
Results and Discussion
The “Modular Process Stream” approach allows the perpetuation of some established techniques such as the use of septic tanks and the promotion of biological reactions rather than mechanical processes. These are supported where necessary by “higher-tech” options which help satisfy health and related concerns and offer failsafe measures for events such as system overload as illustrated in Figures 1-3, Modular Process Stream.
A discussion of the four basic elements of the process stream follows:
a. Biological Augmentation
Systems make use of a proprietary technique for microbial balancing (AP 737685)
employing a multi-point, low dose, constant inoculation pattern which allows a partially self-perpetuating culture of organisms to develop and which overcomes environmental shock loads normally experienced by introduced organisms. With use of EM®, cultures are adaptive and persistent. Where inoculation is maintained, odour control is constant throughout a treatment system, and systems demonstrate stability of biological activity despite fluctuating loads. EM® demonstrates an ability to begin organic treatment of effluent in collection networks prior to a conventional treatment plant.
Table 1 shows reductions of biological load gained in a dosed collection system only (prior to Treatment Plant) over a seven month trial in one system.
Use of EM® has particular benefits in advanced sedimentation and consumption of solids. A significant concern in remote sites is the periodic removal of accumulated solids from septic tanks or similar chambers. Table 2 - Sludge readings, show collated data from primary collection chambers at a number of sites over a two year period. To date none of the sites employing EM® in an enhanced sedimentation phase has required a pump-out.
Inclusion of aeration and settlement chambers including the use of low-energy flow balancing and frictionless aeration compressors make these standard elements very user friendly.
d. Oxidation and Advanced Oxidation
For sites where footprint size of the treatment plant limits biological reaction time, a true rapid oxidation process using ozone (generated on site) offers considerable benefit in reduction of BOD and TSS to consistently outperform Advanced Wastewater treatment guidelines for these indicators. A proprietary technique APP uses Residual Ozone and UV in synergy to provide a double barrier for pathogen control and a significant ongoing benefit in terms of residual oxidation potential without the use of chlorine. In addition, the advanced oxidation process allows for almost complete removal of BOD and TSS. Final waters can be left with consistently high and persistent levels of DO and show little or no pathogen re-growth. This allows reuse with confidence in high-impact areas such as resorts and commercial establishments. (Table 3)
A significant result observed in these systems is the formation of high levels of dissolved oxygen in final waters. Boon and Lister (1975) have shown that presence of dissolved oxygen mitigates against formation of odorous compounds (particularly hydrogen sulphide) in effluent waters. In addition, high levels of dissolved oxygen (DO) which persist in final effluent waters indicate a residual oxidation potential gained without the introduction of chlorine. This represents a significant cost saving for operators and an environmental benefit in reduced formation of chloride compounds.
A modular process stream approach to waste water treatment offers a stable and flexible treatment process especially suited to sensitive and remote sites. Use of low-tech processes backed by consistent augmentation with effective microorganisms and advanced oxidation allows extremely high treatment outcomes in a low maintenance environment.
The production of high and persistent DO in final waters allows little or no pathogen re-growth and permits the storage and re-use of effluent in a range of circumstances without odour generation.
AP. Australian Patent 737685, Method of Treating Waste Water, Bellamy, K.M., Newton R.K.
APP. Australian Provisional Patent PR5732, Method and Apparatus for Water Treatment.
Boon, A.G. and A.R. Lister. 1975. Formation of sulphide in rising main sewers and its prevention by injection of oxygen, Progress in Water Technology, 7 : (2)
EM Inoculation Process - Island Resort
Modular Process Stream - Treatment Plant site
EM® EFFECT TO REDUCE SLUDGE IN WASTE WATER TREATMENT
Reported by Hiroyuki Arichi,
Chief of Operation Adjustment Tsuruoka City Waste Treatment Center of Tsuruoka City
About the reporter:
Born in Tsuruoka City of Yamagata prefecture in 1960. Worked for Tsuruoka City Waste Treatment Center since 1993 with successful results in improving waste water system, in reviewing sludge treatment system to improve and expand the system. Published in professional journals; “Experimental Devise to isolate Mercury Amalgam by Centrifuge”, “Status of Compost Use in Tsuruoka City”, “Effect of Inorganic Chloride in Compost Fermentation Process”.
Sludge from waste water system has become a big problem all over Japan due to the difficulty of obtaining appropriate dumping ground. In Tsuruoka City, all sludge from waste water systems are composted. However, the amount of sludge has been increasing to near the limit of its capacity to compost. Therefore, ways to reduce the amount of sludge have been looked into as an alternative, and EM was experimentally applied to oxidation ditch to test its effectiveness to suppress the amount of sludge.
The experiment was conducted at one of the City’s small waste water treatment centers, Yunohama Treatment Center. The Center started its operation in 1992 as an oxidation ditch method treatment facility to preserve quality water for Yunohama hot spring resort area. The planned capacity of the facility is 3,000 m3/day, and the actual volume during the experiment was approximately 1,000 m3/day.
During the experiment of EM application, scum generation was suppressed, and ideal operating condition was maintained. The primary and the secondary effects of EM application and reduction of sludge were remarkable. It was also effective in saving some costs. The report explains details of one year experiment.
EM EFFECT TO REDUCE SLUDGE IN WASTE WATER TREATMENT
Reported by Hiroyuki Arichi
Sludge from waste water treatment has become a big problem because of the difficulty of securing appropriate dumping sites. In Tsuruoka city, all sludge from waste water system has teen composted and returned to soil. However, the amount of sludge has been increasing to the limit of the city’s capacity to compost. Therefore, effective ways to reduce the amount of sludge have been looked into. As one of the alternatives, EM application was experimented for about one year to an oxidation ditch method treatment facility. I like to report the result of the experiment.
The experiment to apply EM was conducted in one of the city’s small water treatment facilities, Yunohama treatment center. The center started its operation in 1992 as an oxidation ditch method treatment facility to preserve quality water for Yunohama hot spring resort area. The planned capacity of the facility is 3,000 cubic meters (per day), and the actual volume treated during the experiment was approximately 1,000 cubic meters.
1) Extending EM
Ten litters of EM-1 and 7 litters of molasses were mixed with the after-treatment water to make a total mixture of a half or one cubic meter, and the mixture was left at the temperature of 35 Celsius for one week. During the extension, lactic acid bacteria multiply first and lower acid (pH) level. The extension is considered completed when acid level comes down to around 3.5 pH, and the color turns reddish brown from dark brown.
2) How to apply EM
One cubic meter of the extended EM was added to a sedimentation pond once a week. It was suggested that adding EM by several drops at a time for a prolonged period of time is preferable. However, the experimental site is located far from the city and not easy to reach, the total required amount was added at one time. The amount added was approximately 140 parts per million (ppm).
3) Experimental Period
The experimental period was set for one year from June 1996 through May 1997, and the period from June 1995 through May 1996 was selected as the control period.
1) Estimated Amount of Solid Substances
Based on the experimental results, the amount of solid substances per month and per day were estimated. Taking into consideration of changes in surplus sludge due to fluctuation of MLSS (mixed liquid suspended solid) density, the amount of solid substances was calculated as follows:
DS = DS1 + (DS3 - DS2)
Whereas: DS = amount of average solid substances per day (kg)
DS1 = amount of average solid substances per day (kg)
DS = DS1 + (DS3 - DS2)
Whereas: DS = amount of average solid substances per day (kg)
DS1 = amount of average solid substances per day (kg)
DS2 = amount of solid substances in a response tank in the current month divided by the number of days (kg)
DS3 = amount of solid substances in a response tank in the following month divided by the number of days (kg)
2) Estimate of Theoretical Volume of Solid Substances
A ratio of solid substances (DS) in relation to the amount of removed solid substances (SS) in the control period was calculated, and the ratio was applied to the amount of removed solid substances (SS1) in the experimental period to estimate a theoretical amount of solid substances in the following formula:
DSx = (DS/SS) * SS1
Whereas: DSx = Theoretical amount of solid substances (kg)
DS = Accumulated amount of solid substances per day in the control period (kg)
SS = Removed amount of solid substances per day in the control period (kg)
SS1 = Removed amount of solid substance per day in the experimentalperiod (kg)
Actual amount of solid substances and theoretical amount of solid substances were compared in Chart-1 and Graph-1. Provided that the other conditions are equal. EM application reduced the amount of solid substances by 32.5%.
4) Sludge Retention Time (SRT)
Average SRT during the experimental period was 50.8 days and 25.6 days during the control period. Therefore, the amount of solid substances must be evaluated in relation to (biochemical) respiration of activated sludge due to increased SRT. A comparison of SRT during the control period and the experimental period is shown in Graph-2.
5) Reduction of Solid Substances due to (Biochemical) Respiration
The Graph-3 shows the solid substances in the control period: X axis represents SRT, and Y axis represents the amount of solid substances.
Y = 137 - 1.19X
6) A correction to Estimated Amount of Solid Substances
As shown in the previous formula, the amount of solid substances reduced by 1.19 kg per one SRT day. Therefore, EM application reduced solid substances by 16.4% when biochemical respiration of the activated sludge is taken into consideration.
The actual amount of solid substances was compared to the corrected theoretical amount of solid substances in Chart-2 and Graph-4. When reduction due to biochemical respiration of the activated sludge because of SRT increase. EM application reduced the solid substances by approximately 16.4%.
EVALUATION OF EM APPLICATION
1) Evaluation Specific to the Yunohama Treatment Center
Yunohama center had been forced to operate with short SRT in order to suppress scum which was constantly generated by actinomycetes since its opening in 1992. As a result. biochemical respiration of the activated sludge was suppressed, and relatively large amount of sludge accumulated for an oxidation ditch method facility. However, during EM application, scum generation was suppressed. Therefore, it was made possible to set sludge retention time (SRT) closer to the standard value for an oxidation ditch method and consequently to activate biochemical respiration of the activated sludge. This resulted in reduction of solid substances by 32.5%.
The accumulated sludge is removed and transferred to a sludge treatment center in the city. The cost incurred to remove and transfer accumulated sludge was reduced to 92%, while the amount of waste water treated during the experimental period increased to 123%. This is translated to the savings of approximately 2 million yen per year.
The cost for EM is approximately one million yen per year. Therefore, EM application is economical. There are other chemicals available to suppress scum, but they are expensive and not economical.
2) General Evaluation
In the treatment facilities where increase in sludge retention time (SRT) is not needed, cost savings must be examined closely before determining EM application. The cost of EM and man power required to extend EM against savings from reduction of cost due to reduced accumulated sludge. In most treatment facilities, however, 16.4% savings are significant and economical.
I heard that there is a treatment method called JALUS-III. I understand that, in this method, advantages of faster reaction of aerobic treatment and sludge reduction effect of anaerobic method are combined to compliment each other. EM application, I think, facilitates effect of different microorganisms and reduces accumulated sludge as a result. However, it is not commonly practiced yet, and no standard manual was available to guide our experiment. In Tsuruoka city, we plan to continue the experiment of EM application, and we like to have opportunities to share experiences that other treatment facilities have had with EM application.
Technical cooperation provided by: Mr. Yoshikazu Shinkawa, Section Chief of EM
Laboratory of International Nature Farming Research Center
Mr. Shigeomi Asai, Researcher of EM World