温度对超磁分离初沉污泥水解酸化的影响

Effect of temperature on hydrolysis and acidification of ReCoMag separated primary sludge

以超磁分离后初沉污泥作为研究对象,在维持初始pH在7.4~7.8的条件下,分别控制温度在20、25、30和35℃,探究温度对超磁分离初沉污泥厌氧水解酸化产物及产率的影响。结果表明,温度的升高加速了超磁分离初沉污泥的水解酸化。35℃时,SCOD在第3天即达到峰值970.32 mg·L-1,VFAs也达到峰值295.9 mg·L-1,此时,VFAs中含量最高的为乙酸217.1 mg·L-1,乙酸占比为73.3%;而25℃时,其占比为68%。超磁分离初沉污泥水解酸化获取内碳源的同时还伴随着N元素的释放,且温度越高,TN和NH4+-N的释放越明显。由于系统中聚合氯化铝((Al2(OH)nCl6-n)m,PAC)的存在,所以并没有P元素的释放。在30℃的反应温度下,超磁分离初沉污泥水解酸化即可以获取更多的碳源,又可以避免产生过高的N、P负荷。

In this study,the effects of temperatures at 20,25,30 and 35℃on anaerobic hydrolysis acidification products and productivity of ReCoMag separated primary sludge were investigated.The results showed that the increase of temperature accelerated the hydrolysis and acidification of the ReCoMag separated primary sludge.At 35℃,SCOD and VFAs reached their own peak values of 970.32 mg·L-1 and 295.9 mg·L-1 on the 3 rd day of anaerobic hydrolysis acidification process,respectively,and acetic acid in VFAs showed the highest content of 217.1 mg·L-1 and its ratio was 73.3%,while its ratio was 68%at 25℃.In addition,the release of N element occurred as autochthonous carbon was obtained from anaerobic hydrolysis acidification of ReCoMag separated primary sludge,and TN and ammonia nitrogen release were more significant at higher temperature.The polymerized aluminum chloride((Al2(OH)nCl6-n)m,PAC)in the system resulted in no P element release.At 30℃,the anaerobic hydrolysis acidification of ReCoMag separated primary sludge could obtain more carbon sources,and avoid excessive yields of N and P loads.