Study On The Characteristics Of Exogenous Auxiliaries On Biogas Production From Anaerobic Fermentation Of Cow Dung

At present,it is a hot spot for research to promote the gas production of biogas fermentation project by adding exogenous auxiliaries of trace elements.Therefore,this article selects the magnet powders and banana skin powders that are rich in trace elements and are cheap and available as an external aid.Based on the anaerobic fermentation experiment of a single substrate,cow manure,we explore the use of magnetic powder and banana skin powder composites.The optimum ratio of the source additives,and then the anaerobic fermentation conditions optimization experiments for the composite external additives,provide some theoretical guidance and reference significance for improving the difficulties faced by the biogas fermentation engineering in the cold region of Inner Mongolia and improving the utilization of livestock manure.In the experiment,the optimum addition amount of single powder was obtained by adding single magnetite and banana bark powder into 1 %,3 %,5 %,7 % and 9 % of cow dung TS.The final use of solids content(7 %,8 %,9 %,10 %,11 %),anaerobic sludge: substrate quality(20 %,30 %,40 %,50 %,60 %),temperature(low temperature 20 °C,Medium temperature 35 ?,high temperature 50 ?)under different factors and different levels of single factor fermentation experiments tocompare the differences of different levels,analyze the reasons and obtain the conditions of compound excipients fermentation optimization conditions.The conclusion as below:(1)The 3.3915 g of magnetite powder with a total solid mass fraction of cow manure of 7 % and 0.4845 g of banana peel powder with a total solid mass fraction of 1 % were used as an external aid and were added to the fermentation system.The biogas production in the fermentation system was 10490 ml and 10075 ml,respectively.The unit gas production rate was 216.51 ml/g TS and 207.94 ml/g TS respectively,an increase of 30.96 % and 25.78 % compared with the blank experiment.(2)The compound exogenous adjuvant composed of 3.3915 g of magnetite powder with a total solid mass fraction of cow dung and 0.4845 g of banana peel powder with a total solid content of cow dung of 1 % during the fermentation period is 12550 ml,and the unit gas production rate is 252.84ml/g TS,compared with single addition experiment and blank experiment,increased 19.64 %,24.57 %,56.68 %;(3)After the fermentation conditions were optimized,the fermentation was performed under the conditions of high temperature 50 ?,total solid mass fraction of 8 %,and anaerobic sludge:substrate mass ratio of 50 %.