The Study Of Biogas Production From Arundo Donax Cv.lvzhou No.1 By High-Temperature Fermention And The Pulping Technology Of Biogas Residue

Based on the energy plant Arundo donax cv.Lvzhou No.las materials,From "Changes in nutrient compositions of Arundo donax cv.Lvzhou No.1 at different growth Stages"?"Effects of biogas production by high-temperature fermentation","Relations between microorganism structure and function in methanogenesis," and "Arundo donax cv.Lvzhou No.1 and its biogas slag pulping processes" aspect,in-depth study of the potential of Arundo donax cv.Lvzhou No.1 as a modern biogas industry and raw materials for pulping,and the relationship between microbial community structure and function during high temperature fermentation to produce biogas,in order to provide a theoretical basis and technical support for the industrialization of Arundo donax cv.Lvzhou No.1.To provide theoretical basis and technical support for the industrial utilization of Arundo donax cv.Lvzhou No.1,this article takes Arundo donaxcv.Lvzhou No.las raw material to study on its potential of being the row material in modern biogas and pulp-making industry,as well as the relationship between the structure and function of microbial community in the process of biogas production at high temperature in four aspects:"Changes in nutrient compositions of Arundo donax cv.Lvzhou No.1 at different growth Stages"?"Effects of biogas production by high-temperature fermentation","Relations between microorganism structure and function in methanogenesis," and " Arundo donax cv.Lvzhou No.1 and its biogas slag pulping processes"(1)Changes of nutrient composition of Arundo donax cv.Lvzhou No.1 in different periodsArundo donax cv.Lvzhou No.1 was a period of rapid growth from 1 to 180 days,and dry matter reached the maximum accumulation rate at the time of about 90 days,reaching 157.41g/plant-month.With the extension of the growth period,the contents of cellulose,hemicellulose and lignin of Arundo donax cv.Lvzhou No.1 are increasing,and the total fiber content of Arundo donax cv.Lvzhou No.1 is as high as 85%at the later stage of growth.In the first four months,the carbohydrate content increased first and then decreased,highest content was 10.1%at the three-month growth period.The crude protein content decreased continuously from 10.3%to 4.3%.The crude fat content was always low,stays at 1.5%.(2)Effect of biogas production by high-temperature fermentation of Arundo donax cv.Lvzhou No.1The Arundo donax cv.Lvzhou No.1 gas production effect of different growth periods differed greatly.The Arundo donax cv.Lvzhou No.1 gas production effect of the first five months was better,and it was more suitable as a fermentation raw material,especially the Arundo donax cv.Lvzhou No.1 with a growth period of 2 months.The most appropriate,the total gas production and total methane production reached 317.2mL/g TS and 236.6mL/g TS,respectively.According to the monthly average accumulated dry matter production gas,Arundo donax cv.Lvzhou No.1 reached 49222.1mL at 3 months of growth,which is the best harvest period.(3)Study on the structure of bacteria during high temperature fermentationIn the process of high-temperature fermentation of Arundo donax cv.Lvzhou No.1,the main bacterial phylum was Firmicutes,followed by Proteobacteria.The main archaeal phylum is Euryarchaeota.The dominant bacterial genus was Sedimentibacter during the high-temperature fermentation of Arundo donax cv.Lvzhou No.1.Another predominant bacterial genus was Tepidiphilus during the fermentation prophase and peak gas production phases.Another dominant bacterial genus during the stable gas production phase was Gelria.The main archaeal genus is Methanoculleus.The cellulose content reached a maximum of 52.90%on the second day of fermentation.At this time,the lignin content was 28.35%,and the hemicellulose content was always maintained at about 8.5%.The degradation rate of hemicellulose was the highest,and the degradation rate reached 41.78%at the end of fermentation.The cellulose degradation rate was 27.99%.The lowest degradation rate is lignin,which is 14.46%.The organic acid in the biogas slurry is dominated by acetic acid,peaks on the first day of fermentation,and then gradually decreases.During the high-temperature fermentation process of Arundo donax cv.Lvzhou No.1,the predominant bacterial flora is always related to the degradation of organic matter,acetogenesis,and hydrogen production,while the predominant bacterial flora of archaea is always associated with methanogenic function.(4)Arundo donax cv.Lvzhou No.1 and its high-temperature fermentation biogas residue pulping processArundo donax cv.Lvzhou No.1 achieved 43.30%cellulose content for 3 months after its growth.After 5 months of growth,its cellulose content was maintained at about 46.5%.In this study,we explored the Arundo donax cv.Lvzhou No.1 and its biogas residue pulping parameters:20%alkali content(calculated as Na2O);18%sulfur content(as Na2O);maximum temperature 170?,heating time 2h Incubation time 70min;liquid ratio 1:4,can be made better than the coarse pulp(Kapber pulp 21.5,viscosity 831;biogas slurry Kappa 17.3,viscosity 763).The ultrasonic assisted pulping process of Arundo donax cv.Lvzhou No.1 and its biogas residue is as follows:pretreatment:ultrasonic frequency 20kHZ;temperature 100?;alkali amount 3%(calculated by Na2O);sulfurization degree 3%(calculated by Na2O);Time 3h.Cooked pulp:the amount of alkali used 3%(calculated by Na2O);sulfurization degree 2%(calculated by Na2O);maximum temperature 170?,heating time 2h;holding time 1.5h;prepared grass pulp Kappa value 21.9,viscosity 837;Biogas slurry Kappa number 22.4,viscosity 782.