基于复合絮凝剂的SBR工艺中试研究

为解决传统活性污泥法处理能力较低及占地大的问题,利用纳米型复合絮凝剂可使活性污泥快速沉降的特性,采用基于纳米型复合絮凝剂的SBR工艺处理市政污水。在SBR中试装置中,当纳米型复合絮凝剂投加量为20μL/L时,长期运行结果显示污泥性能稳定,污泥容积指数(SV1)<50mL/g,表明污泥沉降速度已达到好氧颗粒污泥的水平。纳米型复合絮凝剂投加到水体后,通过吸附电中和作用促进絮凝,并利用大分子有机物的吸附架桥和卷扫等辅助作用,使污泥絮体及小颗粒迅速聚集成团下降,显著提升了出水水质。基于该纳米型复合絮凝剂的SBR出水水质可达到《城镇污水处理厂污染物排放标准》(GB18918-2002)的一级A要求。综上,该工艺适用于污水处理厂提标改造和延缓扩容的工程实践。

Study on Pilot-scale SBR Process Based on Composite Flocculant

In order to solve the problem of low treating capacity and large footprint for the traditional activated sludge process, municipal wastewater was treated by SBR process based on nano?type composite flocculant through its property to accelerate rapid sedimentation of activated sludge. When the dosage of nano-type composite flocculant was 20μL/L, the Iong-tenn operation results showed that the sludge was stable and sludge volume index ( SVI) was less than 50mL/g in the pilot-scale SBR, which indicated that the sludge settling velocity was equivalent to that of aerobic granular sludge. The addition of nano-type composite flocculant could accelerate the rapid aggregation and sedimentation of flocs and small particles through adsorption & electrical neutralization, adsorption bridging of macromolecular organics and auxiliary functions such as sweeping, which eventually improved the effluent quality. The effluent quality of SBR process based on composite flocculant could meet the first class A standard of Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant ( GB 18918-2002 ). Therefore, the process is applicable for upgrading & reconstmction and delaying expansion of sewage treatment plants.