低声能密度超声波破解污泥的效果研究

Effect of low energy density ultrasonic disintegration on the excess sludge

以生活污水处理厂污泥为研究对象,采用超声波技术进行污泥破解,研究不同声能密度和超声作用时间对污泥预处理效果的影响。结果表明,低声能密度超声波在120min内可破碎污泥絮体,分解细胞壁,使胞内有机物溶出;延长超声作用时间、增加声能密度均有助于污泥中有机物、氮、磷等物质的释放,当声能密度为0.10 W/mL、超声作用时间为120 min时,溶解性COD(SCOD)、可溶性蛋白质、可溶性多糖、TN、氨氮、TP、正磷酸盐的浓度较破解前分别提高了29.99、44.49、17.31、14.06、3.19、1.35、1.00倍;破解污泥释放出的氮以有机氮为主,磷的释放作用不明显。利用Pearson相关性分析得知,在声能密度变化条件下,除TP外,SCOD、可溶性蛋白质、可溶性多糖、TN、氨氮、正磷酸盐之间均呈极显著相关(p<0.01);在超声作用时间变化条件下,各指标间均呈极显著相关(p<0.01)。

The effect of different sound energy density and action time on sludge pretreatment by ultrasonication was studied using excess sludge from sewage treatment plant. The results showed that the low energy density ultrasonic could disintegrate the sludge floc,decompose the cell wall and release organic matters of cell in 120 min;extending the ultrasonication action time and increasing the sound energy density was helpful to release of organic matters, nitrogen and phosphorus. When the excess sludge was pretreated under sound energy density of 0.10 W/mL and action time of 120 min, the density of SCOD, soluble protein, soluble polysaccharides, total nitrogen, ammonia nitrogen, total phosphorus and orthophosphate increased by 29.99,44.49,17.31,14.06,3.19,1.35,1.00 times of the original samples;organic nitrogen was the major from released nitrogen, the release effect of phosphorus was not notable. Using Pearson correlation analysis, it was found that there were extremely significant correlations between the density of dissolved substances including （SCOD, soluble protein, soluble polysaecharides, total nitrogen, ammonia nitrogen, total phosphorus,orthophosphate） except total phosphorus with energy density increasing; with action time increasing, the density of all dissolved substances were extremely significant.