垃圾渗滤液膜后浓缩液混凝预处理

垃圾渗滤液膜后浓缩液是垃圾渗滤液经膜技术处理过程中产生的一种成分复杂、难以生物降解的高浓度有机废水,由于其具有高化学需氧量(chemical oxygen demand,COD)、高氨氮、高盐等特点,盐分达到饱和状态后无法结晶析出,致使后续的蒸汽机械再压缩工艺难以进行.为了后续处理工艺能够顺利进行,研究以三氯化铁、六水...

Coagulation pretreatment of concentrated liquid behind landfill leachate membrane

The concentrated liquid behind a landfill leachate membrane is a type of high-concentration organic wastewater generated during the leachate membrane treatment of landfills. It has a complex composition and is difficult to process via biodegradation. Because of its high chemical oxygen demand (COD), high ammonia nitrogen, high salt content, and other characteristics, the salt cannot crystallize and precipitate smoothly after reaching the saturated state, making it difficult to execute the follow-up mechanical vapor recompression process. To execute the follow-up treatment process smoothly, ferric chloride, aluminum chloride hexahydrate, polyaluminum chloride, and polyaluminum ferric chloride were used as coagulants; polyacrylamide was used as a coagulant aid; and the removal rate of COD was used as an evaluation parameter to coagulate the post-membrane concentrated liquid of a waste treatment plant in Jinan, and the optimal operating conditions were obtained. Results show that ferric chloride is the best coagulant. When FeCl₃ dosage was 0.64 g/L, polyacrylamide dosage was 4 mg/L, and pH was 6, the removal rate of COD was the highest (80.6%).