新型垂直流人工湿地组合工艺处理剩余污泥实验研究

剩余污泥是污水处理过程产生的主要副产品和有机废物,它的处理与处置是污水处理的重要组成部分.通过6个月的实验室模拟,研究了一种新型垂直流人工湿地组合工艺对剩余污泥的脱水和渗滤液的净化效果.结果表明,随着停留时间的增长污泥含水率和挥发性固体呈下降趋势,脱水后污泥含水率为40%,挥发性固体去除率达48.2%.在实验期间,共有392 L新鲜剩余污泥得到处理,获得10.3 L干污泥,污泥体积减小97.4%.湿地床表面污泥以平均每月0.87 cm的速度增厚,到试验结束时为5.23 cm深.组合系统以20.0 L(/m2.d)的污泥负荷间歇进泥方式运行,其污泥渗滤液的TN,TP和COD的平均去除率可分别达75.2%,97.3%和78.4%.结果说明该垂直流人工湿地组合系统可以作为传统污泥处置的一个替代方法,是一种建造简单、维护成本低的生态处理方法.

Treatment and Dewatering of Sewage Sludge by an Innovative Vertical-flow Constructed Wetlands Combination Process

Sewage sludge is the main organic waste end product generated in wastewater treatment processing, and its treatment and handling are today a major issue in wastewater treatment plants. Laboratory-scale experimental results indicated that the system in this study promotes sludge dewatering, as well as sludge water purification. The sludge water content and VS tend to decrease with increasing sludge retention time. The final product is sludge with a water content of around 40%;and the VS average removal rate was 48.2%. Approximately 392 L of fresh sludge was introduced totally and 10.3 L dewatered sludge accumulated during the experimental period, corresponding to a sludge volume reduction of 97.4%. The sludge depth was 5.23 cm at the end with an increasing rate about 0.87 cm per month. Based on the sludge loading rate of 20.0 L/（m2·d）and an intermittently loaded model, the system could achieve a constant nutrient removal rate, with average percentages of removal being 75.2%, 97.3% and 78.4% for TN,TP and COD, respectively. The results showed that on-site treatment of sewage sludge with this uncomplicated, low-maintenance ecology technology can offer an alternative to conventional sludge treatment.