摘要:
某钢铁联合企业拟采用循环结晶造粒流化床+混凝+双极膜电渗析+二次反渗透工艺处理该企业废水处理系统的一次反渗透浓水。为验证工程应用的可行性,通过中试试验考察了循环结晶造粒流化床对一次反渗透浓水的除硬效果,探讨了该工艺中碱的种类与投加量对出水水质的影响,并采用连续运行的方式考察了该流化床的运行稳定性、流化床硬度去除规律以及流化床晶体投排依据。在流化床浓水上升流速为80 m/h,投加600 mg/L的NaOH调节浓水pH=10.95时,流化床出水总硬度、Ca2+质量浓度、Mg2+质量浓度分别为315.98、78.43、28.23 mg/L,相应的去除率分别为82.61%、85.42%、73.75%;此外,色度和TOC去除率分别达到99.60%和51.94%。流化床出水经过混凝除浊后浊度小于1 NTU,满足后续工段进水要求。连续运行试验结果表明,流化床运行稳定,晶体投排对系统运行性能无影响,进水压强与床层高度呈正相关性,可以通过观测压强控制晶体投排。
关键词:
化学结晶,
钢铁工业废水处理,
除硬,
除浊
Abstract:
A steel integrated enterprise intended to adopt a combining treatment process of circulating crystallization granulation fluidized bed+coagulation+bipolar membrane electrodialysis+secondary reverse osmosis to treat the primary reverse osmosis concentrated water from its wastewater treatment system. To verify the feasibility of the engineering application, a pilot test was conducted to investigate the hardness removal effect of the circulating crystallization granulation fluidized bed on the primary reverse osmosis concentrated water of the enterprise. The influence of the type and dosage of alkali in the process on the effluent water quality was explored, and the operational stability, hardness removal law, and crystal feeding and discharging basis of the fluidized bed were investigated by continuous operation. When the flow rate of the concentrated water in the fluidized bed was 80 m/h, pH of the concentrated water was adjusted to 10.95 by adding 600 mg/L NaOH, and the total hardness, Ca2+ and Mg2+ mass concentrations in the effluent of the fluidized bed were 315.98, 78.43, and 28.23 mg/L, respectively, and the corresponding removal rates were 82.61%, 85.42%, and 73.75%, respectively. In addition, the removal rates of chromaticity and TOC reached 99.60% and 51.94%, respectively. The effluent from the fluidized bed was treated with coagulation to remove turbidity, and the turbidity was less than 1 NTU, which met the requirements for incoming water quality in subsequent sections. The continuous test results showed that the fluidized bed operated stably, and the crystal feeding and discharging had no effect on the system performance. The inlet pressure was positively correlated with the bed height, so the crystal feeding and discharging could be controlled by observing the pressure.
Key words:
chemical crystallization,
wastewater treatment in the steel industry,
hardness removal,
turbidity removal
中图分类号:
罗睿, 雷国元, 周顺明, 胡学文, 周达, 马肖, 吴思. 结晶流化床去除钢铁企业反渗透浓水硬度的中试研究[J]. 工业水处理, 2025, 45(6): 179-186.
Rui LUO, Guoyuan LEI, Shunming ZHOU, Xuewen HU, Da ZHOU, Xiao MA, Si WU. Pilot study on the removal of hardness of reverse osmosis concentrated water in steel enterprises by crystallized fluidized bed[J]. Industrial Water Treatment, 2025, 45(6): 179-186.