Acidification And Hydrolysis Of Spent Mushroom And Manure Under Co-fermentation Conditions And The Characteristics Of Gas Production

Energy is an important material basis for human and economic and social development.In order to solve the limited reserves of traditional energy and increasingly serious environmental problems,the development and utilization of renewable biomass energy has become one of the important ways,in which anaerobic digestion of organic biomass is the most cost-effective and environmentally effective way.How to improve anaerobic fermentation efficiency has become a hot issue at present.With the development of intensive animal husbandry around the world,a large number of livestock and poultry waste and agricultural waste become important raw materials for biogas production.This study focused on improving the efficiency of methane production by mixed anaerobic fermentation of edible spent mushroom and cattle manure from agricultural waste.Based on the traditional two-phase anaerobic fermentation process,the optimum conditions of hydrolytic acidification of spent mushroom and manure(different ratio,acidizing time,solid content)and the characteristics of biogas production by anaerobic fermentation of acidizing liquid were studied.It provides scientific basis for anaerobic fermentation of bacteria bran to produce biogas efficiently.The main results are as follows:(1)The effects of different ratio of spent mushroom and manure on substrate decomposition and acid production were studied.According to the TS ratio of 10:0?8:2?6:4?4:6?2:8?0:10 respectively,spent mushroom and manure were acidified for 6 days,and the anaerobic fermentation of acidizing solution was carried out for 31 days each day.The results showed that both hydrolysis and gas production of pure spent mushroom were the worst.After adding cow manure,the acidizing efficiency and gas production content of the system were improved.According to TS ratio of 8:2?6:4?4:6?2:8,the total VFAs increased by 7% and 34.5%,respectively.248%,540%,respectively,methane volume gas production rate and biogas volume gas production rate increased,respectively.It was 105%,240%,348%,487% and 163%,527%,88.6% and 1419% The highest acidizing days of gas production are almost the same as those of the maximum value of s COD dissolution.It isconcluded that the major factor affecting gas production is the dissolution level of soluble organic matter,and the results of collaborative analysis are carried out.Finally,the best proportion is spent mushroom:manure=2:8,acidification time is 3 days.(2)The effects of TS 5%,10% and 15% on acidification and anaerobic fermentation gas production were studied on the basis of TS ratio of spent mushroom and manure at 2:8.The results showed that with the increase of solid content,the accumulation of VFAs and s COD was favorable,and the gas production efficiency of anaerobic fermentation was improved.The cumulative methane yield of hydrolysate acidified for 1 day was the highest when the mixture with high solid content of 15% TS was acidified for 1 day.The results of combined effect analysis showed that the cumulative methane yield of hydrolysate was 16% higher than the theoretical value.Compared with 5% and 10% of TS,the volumetric gas production rate of biogas was increased by 76.4% and 33%,respectively.Methane volumetric gas production rates increased by 114%,respectively.14.8%.(3)Acidizing at 30 ? for 6 days,the effect of temperature on the gas production from anaerobic fermentation of acidizing liquid was studied under the condition of 15% total solid content and 2:8 TS ratio of spent mushroom and manure at 30 ? for 6 days.The results showed that compared with 37 ?,55 ? promoted methane production of pure spent mushroom,and the average cumulative methane production efficiency increased by 104%.