盐分对ASBR装置厌氧污泥产甲烷活性的影响

Effect of Salinity on Methanogenic Activity of Anaerobic Sludge in ASBR Reactor

为研究盐分对处理餐厨垃圾的厌氧污泥产甲烷活性的影响,文章设计了甲烷转化率和日均甲烷产量与进水NaCl浓度负荷的对应关系的两种判断方法,用于确定盐分对厌氧污泥产甲烷活性的毒性负荷。结果表明:中温条件下(30℃~35℃),以模拟餐厨垃圾组分的混合短链脂肪酸为ASBR的进水基质,测定盐分对厌氧污泥产甲烷活性的毒性负荷,发现厌氧污泥对盐分有一定的耐受能力;在进水NaCl浓度≤16 g·L^-1时,对厌氧污泥的产甲烷活性无显著影响,但当进水中的NaCl浓度在24~64 g·L^-1 d^-1之间时,厌氧污泥甲烷活性毒性负荷两种判定方式,即厌氧污泥中的甲烷日均产量和甲烷转化率均与NaCl浓度呈现明显负相关,由此可得,使厌氧污泥活性下降10%和50%的NaCl浓度分别为22.07 g·L^-1,21.73 g·L^-1和51.22 g·L^-1,50.74 g·L^-1。说明适当的盐分可以提升ASBR中厌氧污泥的产甲烷活性,但过高的盐分浓度则会抑制产甲烷活性。

The effect of salinity on methanogenic activity of anaerobic sludge treating kitchen waste was studied in this paper.The toxic loads of salinity on methanogenic activity were determined by the relations between methane conversion rate and influent NaCl loading,or the relation between daily average methane production and influent NaCl loading.The result showed that,under temperature of 30℃~35℃,with the mixed short-chain fatty acid of a simulated kitchen waste as the influent substrate of ASBR reactor,the anaerobic sludge had certain tolerance to salt.When the concentrations of NaCl in influent were less than 16 g·L^-1,there were no significant impact on the methanogenic activity of anaerobic sludge.However,when influent NaCl concentration was between 24~64 g·L^-1 d-1,the daily average methane production and methane conversion rate of anaerobic sludge were negatively correlated with NaCl concentration.The NaCl concentration leading to 10%and 50%of sludge activity reduction were 22.07 g·L^-1,21.73 g·L^-1 and 51.22 g·L^-1,50.74 g·L^-1,respectively.This indicated that appropriate salinity could enhance methanogenic activity of anaerobic sludge in ASBR,but excessive salinity could inhibit methanogenic activity.