The Process Of Biogas Fermentation With Fixed-bed Reactor Using Potato Residues As Feedstock

The potato residues was a good kind of material for biogas production, but the fermentation system ofbiogas was hardly constructed when single potato residues was used as the only feedstock. In this paper, inorder to construct a stable biogas generation system using potato residues as single material, cattle manure wassubstituted for potato residues as the single feedstock on the basis of stable cattle manure fermentation systemof20L anaerobic fermenter until the proportion of potato residues to be the maximum, and a cycle was7daysduring the process of acclimatization. The biogas generation trend of fermentation system was stable from the6th cycle. During the process of acclimatization, pH value was turned from7.5-7.7to6.4-6.9, and pH was heldon6.4-6.9after the system was stable. The peak of biogas production gradually moved forward and it appearedonly one day after adding potato residues after the6th cycle. When the fermentation system kept stable, theaverage daily volume of each generation was10.39L, and the highest gas production volume and rate were10.55L and1.261, respectively. COD removal rate of every cycle was50-55%, and the degradation rate oflignocellulose was18.9%after the system was stable.We had four periods of system of biogas fermentation using potato residues as single feedstock. Themicrobial component diversity of them was analyzed using16S rDNA molecular clone technology.Bacteroidetes was present in each period and other bacterial group was irregularity changes. Archaebacteriagroup which was composed with Methanosaeta sp., Methanocorpusculum sp., Methanoculleus sp. tended tostabilize Carbon dioxide and hydrogen were as substrate for the three kinds of archaebacteria.Feedstock’s pretreatment for biogas fermentation was important, in order to definite the best process ofpretreatment of potato residues, first to determine the optimal C/N, second choosing the effective of factors forpretreatment and going on with single factor experiment, according to the single factor results designorthogonal test, obtain the best pretreatment process. To obtain the best scheme for the pretreatment was5%mesophilic microbial community with cellulose-degradation, the time of acidification2days and40%fowlmanure.Using the best strategy for the pretreatment to deal with potato residues, the factor of influence biogasfermentation were analyzed, according to the single factor results design orthogonal test, obtain the best biogasfermentation technology. The best fermentation process for initial substrate concentration is3%, the initial pH7.0,10%inoculated quantity, the total biogas production3889mL, daily average biogas production of555.6mL, COD removal rate reached49.2%.In order to explore the new technology of biogas fermentation using potato residues as feedstock, addinga fixed-bed which was carbon fiber as material in the system of biogas fermentation. We selected10Lfermentation tank and the cycle of biogas fermentation was13d. The hydraulic retention time, materialconcentration and the time of interval mixing was researched. The optimal process of biogas fermentation withfixed-bed reactorthe was hydraulic retention time of8d, material concentration3%, and the time of intervalmixing for8h. the total biogas production107.769L, daily average biogas production of8.290L, CODremoval rate40.9%.