DBD等离子体及其优化对污泥破解和厌氧产甲烷的影响

Effects of DBD plasma and its optimization on sludge cracking and anaerobic methanogenesis

采用介质阻挡放电(DBD)等离子体预处理剩余污泥,探究放电电压、频率、亚铁离子(Fe2+)投加量和极板构型等因素对污泥破解及厌氧产甲烷的影响。结果表明DBD放电等离子体可以有效强化剩余污泥水解,在板状高压构型,放电间隙为6 mm,放电电压为11 kV,放电频率为11 kHz、放电时间为24 min的条件下,剩余污泥的水解效果最佳,污泥上清液溶解性化学需氧量(SCOD)达到675.35 mg·L^-1,而通过在反应器中投加55 mg·L^-1的Fe2+和改变高压极板构型可以将污泥最佳水解效果分别提升23.29%和29.73%。最后,厌氧消化试验表明剩余污泥经DBD放电预处理后产甲烷潜势得到了提高,极板优化和亚铁优化2个预处理累计产甲烷量较原泥分别增长了54.95%和60.43%,日产甲烷量高峰分别提前了2 d和4 d,且均延长了污泥的高效率产气时间。

Dielectric barrier discharge(DBD)plasma was used to pretreat the remaining sludge,and the effects of factors such as discharge voltage,frequency,ferrous ion(Fe2+)dosage and plate configuration on sludge cracking and anaerobic methane production were investigated.The results showed that DBD discharge plasma can effectively strengthen the remaining sludge hydrolysis.In the plate-like high voltage configuration,the discharge gap was 6 mm,the discharge voltage was 11 kV,the discharge frequency was 11 kHz,and the discharge time was 24 min.The effect was the best,the dissolved chemical oxygen demand(SCOD)of the sludge supernatant reached 675.35 mg·L^-1,and the sludge can be optimized by adding 55 mg·L^-1 Fe2+to the reactor and changing the configuration of the high-pressure plate.The hydrolysis effect was increased by 23.29%and 29.73%,respectively.Finally,the anaerobic digestion test showed that the remaining sludge had increased the methane production potential after the DBD discharge pretreatment,and the cumulative methane production of the two pretreatments,polar plate optimization and ferrous optimization,increased by 54.95%and 60.43%respectively compared with the original sludge.The peak of daily methane production was advanced by 2 d and 4 d,respectively,and both extended the time of high-efficiency gas production from sludge.