Study On Electrochemically Enhanced Anaerobic Microbial Treatment Of Food Waste And Sludge Hydrothermal Dewatering Liquid Mixture

The methane fermentation process of organic matter is completed under the cascade utilization of organic matter by acid-producing fermentation bacteria,hydrogen-and acetogenic bacteria,homo-acetogenic bacteria and methanogenic bacteria.Among the various microbial flora involved in anaerobic biological treatment,the hydrogen-producing acetogenic flora will further convert the Volatile fatty acids(VFAs)such as propionic acid and butyric acid produced by the metabolism of acid-producing fermentation flora into methanogenic flora which can be directly The substrates used,acetic acid and H₂/CO₂,are an important link in the process of organic methane fermentation,and play a vital role in the balance of supply and demand between microorganisms.More and more studies have shown that the anaerobic oxidation of VAFs is the main rate-limiting step in the organic methane fermentation process.To accelerate the anaerobic oxidation of VFAS,Microbial electrophs cell(MEC)can be introduced through external sources to accelerate the accumulation of electricity-producing bacteria and Short-chain fatty acid-oxidation syntrophys(SFAS).In this paper,an Anaerobic baffled reactor(ABR)system is constructed to treat wastewater.After the start-up period and the control period,inoculation of electricity-producing bacteria and SFAS mutual symbiosis sludge,and then introduce MEC to accelerate the development of VFAs.Anaerobic oxidation.R1 is connected to the coupling electrode in the 2.5L ABR small test system,and the mixture of kitchen waste and sludge hydrothermal dehydration liquid is processed under the condition of a medium temperature.At the same time,a set of R2 without external coupling electrode is set up as a Control group.After the strengthening period,the COD removal rate of the R1 system reached 80.6%,which was 5.43%higher than the 75.17%of the R2;the CH4 content of the R1system reached 81.2%,and the CH₄content of the R2 system was 75.44%,plus a coupling electrode The enhancement makes the methane content5.76%higher than the control group,and the methane production rate is49ml/g COD_removedhigher than the control group.High-throughput sequencing was performed on the sludge before and after the enhancement of R1 and R2.Euryarchaeota,Methanobacterium,and Methanosarcina hydrogen-trophic methanogens became the dominant bacteria after enhancement,which improved the methanogenesis efficiency of the pilot system.Based on the ABR small-scale reactor,a pilot-scale ABR with a volume of 360L was built up and scaled up,and the effect of electrochemical enhancement on the anaerobic treatment of microorganisms was investigated under medium temperature conditions.Before and after the enhancement,the COD removal rate of the pilot system increased by 5.79%,and the methane content increased by 5.58%.After the enhancement,the acid production in the first compartment of the system increased,and the consumption of VFAs in the subsequent compartments increased.The p H of the latter four compartments increased by 0.09,0.02,0.10,and 0.14 compared with that before the enhancement,and the methane production content in the subsequent compartments was also increased.Increased to 85.58%.After intensification,the long methane yield can reach up to214.2857ml/g COD_removed.High-throughput sequencing was performed on the sludge in the third compartment before and after the pilot enhancement.After the enhancement,the abundance of Methanobacterium increased from 3.97%to 8.70%,the abundance of Euryarchaeota increased from 7.34%to 14.80%,Euryarchaeota,Methanobacterium and Synergistota Mutual methanogens have become the dominant methanogens,which improves the methanogenic performance of the pilot system.It can be seen from the results of the small-scale and pilot-scale studies that the introduction of MEC into the anaerobic digestion system can significantly improve the efficiency of anaerobic fermentation of food waste and sludge hydrothermal dehydration liquid for methane production.The results of this paper are organic matter anaerobic fermentation production.Methane provides a new technological basis.