厌氧消化技术.ppt

Overview of Anaerobic Biotechnology Definition and Principle of Anaerobic Processes 定义：有机物在无氧或氧的前驱体（如H2O2）的环境中被矿化。根据电子接收的情况，可以将厌氧过程分为厌氧发酵和厌氧呼吸。 Anaerobic Fermentation 厌氧发酵：在黑暗且无外界电子受体的条件下，有机物被严格厌氧或兼性微生物通过内部的氧化还原平衡反应分解代谢。 The product generated during the process accepts the electrons released during the breakdown of organic matter. Thus, organic matter acts as both electron donor and acceptor. In fermentation the substrate is only partially oxidized, and therefore, only a small amount of the energy stored in the substrate is conserved. The major portion of the adenosine triphosphate (ATP) or energy is generated by substrate-level phosphorylation. It is important to point out that the major portion (two-thirds) of methane is produced through anaerobic fermentation in which acetate acts as both electron donor and electron acceptor. Methane production through this route is commonly known as acetotrophic (or acetoclastic) methanogenesis. 葡萄糖厌氧发酵 Anaerobic Respiration 厌氧呼吸正好相反，需要额外的电子受体来接收有机物分解过程中产生的电子。 electron acceptors: CO2, SO42?, or NO3? Both substratelevel phosphorylation and oxidative phosphorylation generate energy (or ATP). The energy released under such a condition is much greater than anaerobic fermentation.   organic matter CO2 CH4 electrons   organic matter NO3- N2 electrons The affinity of microorganism for the electron acceptor is in the following order:O2 NO3? MnO2 FeOH SO42? CO2 Important Considerations in Anaerobic Biotechnology Volumetric Organic Loading Rate biomass yield, substrate utilization rate, HRT and SRT, start-up time, microbiology, environmental factors, reactor configuration Volumetric Organic Loading Rate High-rate anaerobic reactors such as UASB, EGSB, anaerobic filter, and fluidized bed reactors are capable of treating wastewater at VOLR of 10–40 kg COD/