| Based on the review for the research achievement about starch effluent treatment, and considering the conditions and effluent discharging phenomena of starch industry, we designed and manufactured "The Simple Combined Concentrated Organic Effluent Treatment Plant", which is a kind of indoor reaction model of the multiphase anaerobic-aerobic starch effluent technology process. It can be easy to be moved. The vertical baffled reactors were designed for separating multiphase anaerobic, aerobic, deposited reactors with each other. The different reactors of combined system consisted of up and blow-flow reactors. The anaerobic reactor's retained volume was about 6 L, and the aerobic reactor's was also 4 L. The sample injecting valve located the ahead of each reactor.The low loading initiating method adopted. The microorganism assembling form and size were observed by the means of SEM. The separating phenomenon of acid yielding phase, acetic acid yielding phase and methane yielding phase in reaction system were discussed. The COD, pH value and volume loading of each reactor were analyzed in the process of starch effluent treating. The initiative process principle was also studied. The value of COD became lower along with the current, it was the same that the removal efficiency of COD increased. The pH value decreased in the beginning and increased subsequently. The order of different reactors, which contribute to general removing efficiency of COD, was H~1>O>H~2>H~3. The best initiating process conditions of reaction system were determined as follows, temperate, 25~35℃, volume loading, 3.7kg/(m3.d) under this conditions the general removing efficiency of COD was amounted as high as 92%. Microorganism loading became higher along with the increased injecting water volume loading. The order of microorganism loading in each reactor during the same time was H~1>H~2>H~3>0.The best growth conditions of microorganism, such as the pH and temperature, have been controlled in the 90 days stable running. The physical and chemical characters were studied by the means of SEM and chemical analysis. After primary identify, we can conclude that the H~1 reactor was the place for forming acid yielding bacteria floccules, the H~2 reactor was for the acetic acid bacteria grain, the H~3 reactor was for methane bacteria grain, the O reactor was for aerobic microorganism bacteria mainly. The best process parameters are as following: the general volume loading was 10.0 kg/(m3d), the value of COD in aerobic reactor was 3 mg/L, the COD value of injecting water was less than 3238 mg/L, temperature was 25-35 °C, the pH of H~1 and H~2 was 5.0-5.8, the pH in the H~3 was 6.5-7.8.By determining VSS and COD of each reactor, it can be concluded that the order of the microorganism's concentration was O>H~1>H~2>H~3, the order of the microorganism's loading was O>H~3>H~2>H~1, the order of the organics whichtransformed to cell substance was OH^H^H3. We also got the equation between the concentration of microorganism with the removal efficiency of organics and the constant of yield as follows, H1 reactor, y=0.217x4-313.95, yield constant is 0.217 kgVSS/Kg COD. H2 reactor, y=0.160x+6.13, yield constant is 0.160 fcgVSS/Kg COD. H3 reactor, y==0.037x-5.84, yield constant is 0.037 kgVSS/Kg COD. O reactor, y*O.402x+102.82, yield constant is 0.0.402 kgVSSACg COD.The constituent of VFA(Volatile Fatty Acid) in each reactor was analyzed by GC. The content of ammonia nitrogen was monitored by colorimetry. The total removal efficiency of COD was 95.7mg/L under the conditions that temperature was 25-35 °C. The volume loading was less than 5.2 kg/ (m3>d) when the COD of injecting wastewater was less than 1118 mg/L-h, the concentration of ammonia nitrogen at let-out was 7.6mg/L, and the concentration of COD was 49.8 mg/L.The volume of methane in the H3 reactor was detected, which obtained the related equation between the removed amounts of organics with the yield of methane, y=0.34x+9.04. The amount of methane in the process of starch effluent treating can be estimated from t...
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