摘要：

采用硫酸吸收荒煤气中氨气生产硫酸铵过程中，随着硫酸铵母液的循环使用，母液中的金属离子、有机物、氯离子等杂质不断累积，为避免影响硫酸铵产品质量和设备的稳定运行，通常需要置换出部分硫酸铵母液来降低杂质含量。由于被排出的废硫酸铵母液中氨氮、COD、氯离子及金属离子浓度极高，不满足直接排入焦化废水处理系统的水质要求。针对某煤精厂高盐高有机物废硫酸铵母液，采用氨气将硫酸铵母液pH调节至7.5~9.0，使母液中粗吡啶析出后溢流去除，使金属离子形成的氢氧化物沉淀，通过板框压滤机过滤去除，净化后的硫酸铵母液经蒸发结晶回收硫酸铵和氯化铵的混盐，蒸发结晶过程中产生的冷凝水满足焦化废水处理系统进水水质要求，可直接排入焦化废水处理系统，实现了废硫酸铵母液处理的同时回收了粗吡啶和混合铵盐，较直接稀释排入焦化废水处理系统，处理成本降低52.56%，为其他焦化厂或煤精厂废硫酸铵母液的处理提供参考。

关键词: 废硫酸铵母液, 粗吡啶, 硫酸铵回收

Abstract:

In the process of producing ammonium sulfate by absorbing ammonia gas from raw gas with sulfuric acid, impurities such as metal ions, organic matter, and chloride ions in the mother liquor continuously accumulate with the recycle of ammonium sulfate mother liquor. To avoid affecting the quality of ammonium sulfate products and the stable operation of equipment, it is usually necessary to replace part of the mother liquor to reduce the impurity content. Due to the extremely high concentrations of ammonia nitrogen, COD, chloride ions and metal ions in the discharged waste ammonium sulfate mother liquor, it does not meet the water quality requirements for direct discharge into the coking wastewater treatment system. For the high-salt and high-organic waste ammonium sulfate mother liquor of a certain coal refining plant, ammonia gas was used to adjust the pH of the ammonium sulfate mother liquor to 7.5-9.0, so that the crude pyridine in the mother liquor was precipitated and removed through overflow. The hydroxide precipitate formed by metal ions was filtered out through a plate and frame filter press. The purified ammonium sulfate mother liquor was evaporated and crystallized to recover the mixed salts of ammonium sulfate and ammonium chloride. The condensate water produced during the evaporation and crystallization process met the influent water quality requirements and could be directly discharged into the coking wastewater treatment system. This process realized the treatment of waste ammonium sulfate mother liquor while recovered crude pyridine and mixed ammonium salts. Compared with direct dilution and discharge into the coking wastewater treatment system, the treatment cost was reduced by 52.56%, providing a reference for the treatment of waste ammonium sulfate mother liquor in other coking plants or coal refining plants.

Key words: waste ammonium sulfide mother liquor, crude pyridine, ammonium sulfate recovery

中图分类号: 

• X703.1