Research On Hydrogen Production Of Food Waste And Sewage Sludge By Anaerobic Fermentation

With traditional fuel energy decreased and the environment problem deteriorated,the great potential and prospect of renewable energy has been recently realized.Hydrogen production from food waste and sewage sludge by anaerobic fermentation not only can solve the environment pollution of food waste and sewage sludge,but also produce clean energy which is friend for environment.So it is necessary to study on hydrogen production from food waste and sewage sludge by anaerobic fermentation.This paper is divided into two parts.In the first part,due to the lack of basic data about the food waste in china,the present situation and physical-chemical characteristic of MSW in Pu lan dian were analysed.The results show that the proportion of the food waste is very high in MSW,and the food waste, which contains high moisture and a lot of organic component,is suitable for the anaerobic fermentation.In the second part,hydrogen production from food waste and sewage sludge by fermentation was studied,and the experiment results are showed as follow.(1) Hydrogen production of different mixing ratio with no pretreatmentWhen the ratio of food waste and sewage sludge was 4:1,the efficiency of hydrogen production is the best,the highest hydrogen content and cumulative hydrogen production are 15.61%and 2.48ml H₂/gVS,respectively.In this experiment condition,the delay time is long and the cumulative hydrogen production is low.(2) Hydrogen production of inoculum with different pretreatment methodsCompared with three different pretreatment methods,it is found that hydrogen production inoculated heating pretreatment of 85℃is the highest,the highest hydrogen content and cumulative hydrogen production are 21.93%and 12.15mlH₂/gVS,and the cumulative hydrogen production increased by 3.90 times compared with no pretreatment.(3) The effect of different pretreatment on food wasteThe effect of different pretreatment on SCOD and reducing sugar of food waste is studied in different experiment time and conditions.The results show that when the pH is 13, the pretreatment efficiency is the highest.(4) Hydrogen production of alkaline pretreatment in different experiment conditions In the different initial pH,mixing ratio,substrate concentration and particle size,the hydrogen production by anaerobic fermentation is researched,and the best test parameters are determined:the initial pH is 7,the mixing ration of food waste and sewage sludge is 5:1,the substrate concentration is 25 g/L,and the food waste is completely crushed.The least delay time,the highest hydrogen content,the hydrogen production peat rate and the highest cumulative hydrogen production are 0.3 h,59.96%,1.75 mlH₂/(h·gVS) and 57.59 mlH₂/gVS,respectively.(5) Hydrogen production of different pretreatment methodsIn the experiment,sodium hydroxid(NaOH),hydrochloric acid(HCl) and heating solutions are used in the pretreatment of the food waste and sewage sludge.The results show that the heating pretreatment is the best method.The least delay time,the highest hydrogen content,the hydrogen production peat rate and the highest cumulative hydrogen production are 0.3 h, 47.68%,2.89 mlH₂/(h·gVS) and 57.74 mlH₂/gVS,respectively.