Preliminary study on anaerobic fermentation biogas of Chinese herbal residues with pretreatment

Experiment studied how the traditional Chinese herbal residues to anaerobic ferment and produce biogas after compost pretreatment with biogas slurry and NaOH,and the influences of inoculumsize,pH value on the biogas production were studied.The results showed that:the herbal residue can efficient fermentation biogas within a short time after biogas slurry composting pretreatment;the fermentation peak wasof 2 ~10 days,the gas production in this phase are for more than 95% of the total gas production;during thetrial period the residue with the straw biogas slurry pretreatment produced the highest biogas,up to 11 940 mL,and raw materials gas production rate is 54.4 L/kg dry residue.It is not necessary to adjust C/N by adding animal manure in the fermentation process of residue,straw biogas slurry domesticated enrichment conducive to the microorganisms of decomposition of the straw material can greatly enhance the degradation rate of the residues.NaOH pretreatment could significantly improve the potential for gas production of the residues,fermentation lasting and higher total biogas yield.After 10 d's pretreatment with 5%NaOH,raw materials gas production rate is of the 196.8 L/kg dry residue.