水稻秸秆联合剩余污泥共发酵产酸效能探究

目的]研究稻秆与剩余污泥厌氧发酵产酸性能。方法]在总固体浓度为20 g/L条件下,用一定比例的稻秆代替部分剩余污泥,构建共发酵产酸系统,探讨其有机物组分变化及其产酸特性。结果]稻秆的投加能够促进多糖和蛋白溶出,提高SCOD含量,在发酵进行到第4天时,10%预处理稻秆处理和10%稻秆处理发酵体系中SCOD达到最高,分别为3 440和2 810 mg COD/L,与污泥对照相比,分别升高了72.0%和40.5%。与此同时,在发酵结束时,稻秆的投加虽没有增加VFAs积累量,但其在短期内能够促进VFAs转化,缩短发酵时间,在发酵进行到第6天时,与污泥对照组相比,10%预处理稻秆处理中VFAs积累量提升了70.1%。当VFAs积累量趋于稳定时,乙酸和丙酸占总酸的比例和从大到小依次为10%预处理稻秆处理、10%稻秆处理、污泥对照。结论]稻秆的投加能够改善污泥厌氧发酵产酸性能,可为农业废物的资源化利用提供一种有效途径。

Study on Anaerobic Acidification Performance during Co-fermentation of Sewage Sludge and Rice Straw

Objective] To analyze the acid-producing properties of anaerobic fermentation of rice straw and sewage sludge.Method] Under the condition of total solid concentration of 20 g/L for experiment beginning,the co-fermentation system which part of sewage sludge was replaced by a certain proportion of rice straw was constructed.Result]The change of organic components and acid-producing properties during fermentation process was explored,when 10％ rice straw dosing (rice straw mass/mass of rice straw and sludge mixture =1:10) and 10％ pretreated rice straw added in the fermentation system,respectively.The results showed that the addition of rice straw could promote the dissolution of polysaccharides and protein content and increase the SCOD content.At the 4th day of fermentation,the highest SCOD was achieved in the co-fermentation system.The SCOD content in 10％ pretreated rice straw experiment group and 10％ rice straw experiment was 3 440 mg COD/L and 2 810 mg COD/L,which increased by 72.0％ and 40.5％,respectively,compared with the sludge control.Meanwhile,at the end of fermentation,the addition of rice straw did not increase the accumulation of VFAs,but it could promote the conversion of VFAs in the short term and decrease the fermentation period.Compared with the sludge control group at the 6th day of fermentation,the accumulation of VFAs in pretreated rice straw experiment group increased by 70.1％.When amount of VFAs accmnulation stabilized,the ratio of acetic acid and propionic acid to total acid and from large to small were as follows 10％ pretreated rice straw experiment group,10％ rice straw experiment group,sludge control group.Conclusion]The addition of rice straw could improve anaerobic fermentation performance of sewage sludge and provide a effective way in utilization of waste resource of agriculture.