城镇污泥生物沥浸减量试验研究

通过生物沥浸技术实现对城镇污水处理厂污泥减量并最终达到资源化利用的目的，具有非常重要的实际意义。利用可移动集装箱式试验机，采用续批式运行模式对天津本地两处污水处理厂污泥进行生物沥浸减量实验。结果表明，环境温度为15~25℃、曝气量为1.2L/min、反应时间72h，初始批次将260L接种物和0.73kg营养剂投入400L原泥中，按回流比40%进行3批次沥浸实验。当反应结束后，2种污泥3批次的终点pH从沥浸前的5左右可降至3以下。2种污泥的镉、铜、锌、镍平均溶出率都达到80%以上，其中锌、镉的溶出率分别达到了94.26%、86.67%以上，平均溶出效果从高到底依次为锌＞镉＞铜＞镍。汞、铅、砷的平均溶出率最低，分别为21.42%、20.4%、23.52%。2种污泥经生物沥浸固液分离后，泥饼含水率均降至53%以下。向压滤液分别投加4kg/t、2kg/t石灰后，污泥1、2的上部澄清液中氨氮、COD及污泥1的SS都超过了污染物一级排放标准。与原泥相比，粪大肠菌群杀灭率达到99.99%，沥浸过程造成总养分分别损失24.89%、9.31%，有机质也有所损失，泥饼盐分含量超过2.00%。因此，生物沥浸具有很好的应用效果及应用前景，为进一步在本地工程化应用提供了相关依据。

Study on Sludge Reduction by Bioleaching Technology

The paper aims to study sludge reduction in municipal wastewater treatment plant by bioleaching technology and ultimately achieve the purpose of resource utilization, and has practical significance. Three sequencing batches of bioleaching experiments were conducted in two local sewage treatment plants in Tianjin with a movable container testing machine. The results showed that under the condition of 15-25℃, 1.2 L/min of aeration rate and 72 h of reaction time, inputting 260 L initial inoculum and 0.73 kg nutrients into 400 L original mud, 3 batches of leaching experiments were conducted with reflux ratio of 40%. When the reaction time was 72 h, pH value of two kinds of sludge in 3 batches could be reduced from around 5 before leaching to 3 or less. Dissolution rates of cadmium, copper, zinc and nickel of both kinds of sludge reached more than 80% on average, of which, the dissolution rate of zinc and cadmium reached 94.26% and 86.67% . The average dissolution effect from high to low was as follows: zinc ＞ cadmium ＞ Cu＞ Ni. Mercury, lead and arsenic had the lowest average dissolution rate, which was 21.42%, 20.4% and 23.52%, respectively. After bioleaching solid-liquid separation, solid sludge moisture rate was 53% or less. Respectively adding 4 kg/t and 2 kg/t of lime to the liquid after condensation, ammonia, COD of sludge 1 and 2, and SS of sludge 1 exceeded pollutant emission standards in the upper part of the supernatant. Compared with the original mud, fecal coliform kill rate of bioleaching sludge was 99.99% . In the end of the bioleaching process, the total nutrient loss was 24.89% and 9.31% , respectively, and there was also certain loss of organic matters, while solid sludge salt content was more than 2.00%. Therefore, bioleaching technique had good application effect and prospect, and the study provided basis for further local engineering applications.