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Mathematical Modeling And Pilot Experiment Of Two-Phase Anaerobic Digestion And Membrane Bioreactor For Treating Traditional Chinese Medicine Wastewater

Posted on:2010-05-08Degree:DoctorType:Dissertation
Country:ChinaCandidate:X F YanFull Text:PDF
GTID:1101360278496176Subject:Environmental Engineering
Abstract/Summary:PDF Full Text Request
State Environmental Protection "Eleventh Five-Year Plan" pointed out that the form of China's environmental protection is still grim, targets emissions of major pollutants far exceed the capacity of the environment, water environment is very difficult emission reduction targets. At present, the pharmaceutical industry continue to grow and develop, according to statistics, the pharmaceutical industry the country's total industrial output value of 1.7 percent, and accounted for 2% of sewage has become the focus of the State Environmental Protection planning governance, one of 12 industries. Chinese medicine is a high concentration of wastewater refractory organic wastewater, many kinds of organic pollutants, at high concentrations, the use of conventional biological treatment difficult to discharge polluted water. By analyzing the characteristics of traditional Chinese medicine wastewater quality and compare a wide range of wastewater treatment and process routes, and in a small test of research results based on the use of "CSTR acidogenic phase-UASBAF composite methanogenic phase - membrane bioreactor" This technology routes to deal with the types of wastewater pilot program.Through the two-phase anaerobic - membrane bioreactor process wastewater Chinese test pilot study investigated the effect of technology systems, results show that two-phase anaerobic - membrane bioreactor process wastewater of high concentration of Chinese medicine is technically viable, long-term stable operation. Acidogenic phase to start 42 days after the average COD removal rate of 32% ~ 52%, volumetric loading up to 30 ~ 42kgCOD/m3 ? d. Fermentation type was the type of acid-type fermentation, volatile acid content increased to 3.65 percent from 23.09 percent, biodegradability greatly enhanced. Methane-producing phase, after the successful completion of 20 days to start, run stable COD average removal rate was 86.7 percent, the average volume load of 4.5 kgCOD / (m3 ? d). Membrane bioreactor start after the completion of 12 days, the average volume of the load in between 5.0 ~ 6.2kgCOD/m3.d, the effluent COD is less than 50mg / L, can be achieved in the water reuse standards.The use of molecular biology means of two-phase anaerobic - membrane bioreactor process wastewater Chinese pilot test conducted microbiology studied Process Systems population structure and changes in community succession, research results show that the initial reactor ecosystems to determine the reactor quick start and high load and stable operation played a key role. Membrane bioreactor from start-up period to period and stable operation of a total of 12 days, inoculated sludge microbial populations stable than running membrane bioreactor extra two populations. Proved membrane bioreactor rapid succession of microbial communities, membrane bioreactor start-up than ordinary aerobic activated sludge shorter start-up period. Acidogenic reactor and methane-producing reactor inoculated with sludge and return sludge microbial populations rich acidogenic phase reactor mud-like from the start to run a stable, there is a group always exist in the acid production, and to occupy a larger group points, that its phase acidogenic microbial degradation of the main sewage. Methane-producing reactor, the initial phase to determine a better ecosystem, species diversity, reactor, after a relatively short time that reached a stable operation.International water pollution and Control Association IAWQ introduced mathematical model of activated sludge (ASM1) and anaerobic activated sludge mathematical model (ADM1) for the theoretical foundation, established a two-phase anaerobic - Membrane Bioreactor for Treatment of Wastewater mathematical model of traditional Chinese medicine . Simulation results show that the model can simulate the basic two-phase anaerobic - membrane bioreactor operation. ADM1 model can be directly used for CSTR Reactor Simulation, and UASBAF HABR fluid flow within the complex, the study found that the axial dispersion model and the whole series mixed model can better reflect the internal UASBAF Reactor fluid flow state. ASM1 can be effectively simulated membrane bioreactor operation, and can be applied to the model of membrane bioreactor selection evaluation factors. Can be used to process the choice of the size of the various structures and its key operating parameters to identify; to optimize the submerged membrane bioreactor operation and management (for dynamic simulation to find the best working condition MBR).Through the diagnose of the morbidity symptom of the anaerobic wastewater treatment system in the 2nd factory, controlling of the fermentation at the phase of butyric-acid-fermentation was appropriate for the reactor of acid-producing stage to achieve steady and high efficient performance. At the organic loading of 110, the acid-producing reactor could remove 10~15% of COD. Long-term operation under low organic loading was detrimental to the operation of methane-producing stage, based on which, the stage should operated under the conditions as follows:It was proved in this research that it was feasible to restart the anaerobic system after its acidification by inoculating the excess sludge extracted from the settling tank into the anaerobic reactor. Dosing of trace mental materials was found helpful for the system to recover from sick conditions. In this project, the dose of the trace mental were as follows: Fe2+ 1.0mg/L, Co2+ 0.1mg/L and Ni2+ 0.1mg/L.With regard to the separation of the two phase anaerobic process, the reaction course of the separated phase and optimization of the system were also studied. The fermentation in the acid-producing stage should controlled at the phase of butyric-acid-fermentation. As for the methane-producing stage, Methanothrix sp. and Methanosarcina sp.should grow predominant in the granule sludge. In addition, butyric-acid-fermentation in the acid-producing stage was favorable for the formation of granule sludge in the methane-producing stage.
Keywords/Search Tags:two-phase anaerobic-membrane bioreactor (MBR), traditional Chinese medicine (TCM) wastewater, pilot test, DGGE, mathematical model, diagnose
PDF Full Text Request
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