Experimental Study On Anaerobic Digestion Characteristics Of Pork

According to the data,the fatality rate of pigs in China is about 10% every year.Nearly 2 million tons of dead pork need to be treated harmLessly every year,which results in pollution and a great waste of resources.So,in this paper,the anaerobic digestion characteristics of pork were studied by batch anaerobic digestion experiment,and the feasibility of applying anaerobic digestion to the harmLess treatment of dead pigs was explored.In this paper,batch experiments on different parts of pork were carried out to explore the gas production characteristics of different components and the gas production potential of pork.Then the effects of process,pretreatment,temperature,inoculum concentration and organic loading on anaerobic fermentation of mixed pork were studied.Finally,the optimal TS gas production rate under different temperature,inoculum concentration and organic loading conditions was studied by response surface test.The following results are obtained:1,Using pig skin,pork lean pork and pig fat as raw materials,the biogas production experiments were carried out by batch fermentation under the experimental temperature of 30 degrees.The biogas production potential was 1139mL/gTS,1571mL/gTS and 1231mL/gTS or 1159mL/gVS,1687 mL/gVS and 1257 mL/gVS respectively.The results showed that anaerobic digestion could realize the utilization of sick and dead pork resources.2.Mixed pork was used as raw material,and laboratory self-assembled upper drainage fermentation device(device B)and lower drainage fermentation device(device A)were used to carry out experiments.The results showed that the air pressure did have some influence on the pork fermentation process.The*gas*production rate of pork could be increased by 40% under negative pressure in the fermentation device,and the difference of gas production was not significant.At the same time,the anaerobic fat and protein of mixed pork had good synergistic effect,and the gas_production rate of TS and methane_production rate were higher than that of fat and protein fermented alone.3.Compared with untreated TS,the gas production rate of pork treated by HTHP increased by 19.5% and the methane production rate of TS increased by 19.6%,which was higher than that of cooked TS.Both high-temperature and high-pressure treatment and boiling treatment can only destroy the spatial structure of protein,but can not destroy the peptide bond.So both high-temperature and high-pressure treatment and boiling treatment have no effect on the fermentation cycle.However,the two treatments accelerated the fat precipitation rate to varying degrees and advanced the main gas production period.4,The effects of temperature and organic load inoculation on the gas production rate of TS in pork anaerobic digestion were as follows: organic load(g)> inoculum concentration(%)> temperature(?).The optimum conditions of TS gas production rate for pork anaerobic digestion are temperature 36 C,inoculum concentration 6%,organic load 9.2g.Under this condition,the relative error between actual TS gas production rate and theoretical gas production rate is 2.38%.Among them,the interaction between organic load and inoculation amount is obvious,and there is no obvious interaction between temperature and other two factors.In summary,pork can be digested by anaerobic digestion to achieve efficient energy conversion.After a series of optimization experiments,the TS production rate of pork has been significantly increased to 2397 mL/gTS.This experiment provides a reference for the application of anaerobic digestion in the treatment of dead pigs.