Combined Anaerobic Fermentation Characteristics Of Different Raw Materials And Furfural Wastewater

With the rapid development of the chemical industry,the demand for furfural is increasing.Since sulfuric acid was used as the catalyst in the production of furfural,a large amount of sulfuric acid-containing wastewater was generated.The random discharge of wastewater could cause environmental pollution.Because the comprehensive treatment of furfural wastewater was relatively difficult,furfural wastewater had become a bottleneck restricted the development of the industry.The wastewater had a high temperature and the wastewater contained organic substances such as organic acids that could be utilized by anaerobic microorganisms.Therefore,furfural wastewater could not only provide organic acids for anaerobic fermentation microorganisms,but also hydrate and warm the anaerobic fermentation process of solid waste.However,the effect of sulfate-containing furfural wastewater on the anaerobic fermentation process of different raw materials,and the relationship between the amount of furfural wastewater added and the type of anaerobic fermentation substrate still needs to be analyzed.In order to realize the resource utilization of furfural wastewater and solid waste,the anaerobic fermentation experiment of furfural wastewater with corn stover,cow manure and kitchen waste was designed.The gas production performance,organic matter degradation rate,p H,volatile fatty acid and sulfate content in the fermentation broth were analyzed.The main findings and conclusions were obtained as follows.(1)Under moderate temperature conditions,adding proper amount of furfural wastewater to the corn stover fermentation system can increase methane production and promote organic matter degradation.Furfural wastewater accelerated the start-up speed of corn stalk anaerobic fermentation system,removed the sulfate,and helped to adjust the p H value of anaerobic fermentation system and reduced the risk of acidification of corn stover during anaerobic fermentation.The addition of furfural wastewater was 11.4%(J80 group)had the best gas production performance,and the maximum methane yield was 157.31 m L/g VS,which was 45.67%higher than that of the control group.The highest sulfate removal rate was 26.60%;the maximum degradation rates of TS and VS were 34.46% and 45.43%,which were 72.68% and 78.84% higher than that of the control group.(2)Under moderate temperature conditions,adding proper amount of furfural wastewater to the cattle manure fermentation system can increase methane production and promote organic matter degradation,but the combined anaerobic fermentation of cow manure and furfuralwastewater did not remove sulfate in furfural wastewater.The addition of furfural wastewater was16.7%(N100 group)had the best gas production performance,and the maximum methane yield was 132.71 m L/g VS,which was 21.85% higher than that of the control group.The TS and VS degradation rates of the N120 group(the addition of furfural wastewater was 20%)were 33.28%and 37.84%,which were 21.93% and 22.55% higher than the control group,respectively.(3)Under moderate temperature conditions,adding proper amount of furfural wastewater to the kitchen waste fermentation system can increase methane production and promote organic matter degradation.The combined anaerobic fermentation of kitchen waste and furfural wastewater removed the sulfate,helped to adjust the p H value of anaerobic fermentation system and reduced the risk of acidification of kitchen waste during anaerobic fermentation.The addition of furfural wastewater was 13.3%(C80 group)had the best gas production performance,and the maximum methane yield was 477.08 m L/g VS,which was 38.13% higher than that of the control group.When the retention time was 12 days,the sulfate removal rate of the C80 group reaches a maximum of 17.03%.The maximum degradation rates of TS and VS of the C120 group(the addition of furfural wastewater was 20%)were 24.52% and 30.41%,which were 10.30% and24.06% higher than the control group.