Zhang Yan, Zhao Chen, Ren Fangyun, Wang Xiufeng, Sun Xiuping, Zou Yihong, Liu Yucan, Tian Yepeng
School of Civil Engineering, Yantai University, Yantai 264005, China.
School of Civil Engineering, Yantai University, Yantai 264005, China.
Waste Manag. 2023 Jun 1;164:181-190. doi: 10.1016/j.wasman.2023.04.015. Epub 2023 Apr 13.
A small amount of leachate with complex composition will be produced during the compressing of municipal solid waste in refuse transfer stations. In this study, the freeze-melt method, a green and efficient wastewater treatment technology, was used to treat the compressed leachate. The effects of freezing temperature, freezing duration, and ice melting method on the removal rates of contaminants were investigated. The results showed that the freeze-melt method was not selective for the removal of chemical oxygen demand (COD), total organic carbon (TOC), ammonia-nitrogen (NH-N) and total phosphorus (TP). The removal rate of contaminants was positively correlated with freezing temperature and negatively correlated with freezing duration, and the slower the growth rate of ice, the higher the purity of ice. When the compressed leachate was frozen at -15 °C for 42 h, the removal rates of COD, TOC, NH-N and TP were 60.00%, 58.40%, 56.89% and 55.34%, respectively. Contaminants trapped in ice were removed during the melting process, especially in the early stages of melting. The divided melting method was more beneficial than the natural melting method in removing contaminants during the initial stage of melting, which contributes to the reduction of produced water losses. This study provides a new idea for the treatment of small amounts of highly concentrated leachate generated by compression facilities distributed in various corners of the city.
在垃圾转运站对城市固体废物进行压缩处理时，会产生少量成分复杂的渗滤液。本研究采用绿色高效的废水处理技术——冻融法，对压缩渗滤液进行处理。研究了冷冻温度、冷冻时长及融冰方式对污染物去除率的影响。结果表明，冻融法对化学需氧量（COD）、总有机碳（TOC）、氨氮（NH-N）和总磷（TP）的去除没有选择性。污染物去除率与冷冻温度呈正相关，与冷冻时长呈负相关，且结冰速率越慢，冰的纯度越高。当压缩渗滤液在-15℃冷冻42小时时，COD、TOC、NH-N和TP的去除率分别为60.00%、58.40%、56.89%和55.34%。被困在冰中的污染物在融化过程中被去除，尤其是在融化初期。在融化初期，分阶段融化法比自然融化法更有利于去除污染物，这有助于减少产水损失。本研究为处理城市各个角落的压缩设施产生的少量高浓度渗滤液提供了新思路。
