元坝气田蒸发母液深度处理技术研究与工艺设计

元坝气田污水处理厂蒸发母液为三效蒸发系统粗盐结晶后的残液,是复杂组分共存的高盐废水,处理难度极大。研究拟对蒸发母液进行深度处理,通过工艺比选和优化后,蒸发母液经过混凝沉降、CaCl₂除SO2-₄、UV+H₂O₂协同氧化除有机物的组合工艺处理后,出水水质为ρ(固体悬浮物)<50 mg/L,ρ(SO2-₄)为4 200 mg/L,TOC值为459.25 mg/L。出水水质达到厂区采出水处理工艺进水水质要求,可回到厂区水处理工艺及装置进行处理,能有效解决母液处理和积压的难题。该组合处理工艺流程短、简单易维护,在一定程度上实现了蒸发母液的近零排放。 

Study and process design of the advanced treatment of evaporated mother liquor in Yuanba gas field

The mother liquor as the residual liquid was produced after the coarse salt crystallized in the three-effect evaporation system in wastewater treatment plant of Yuanba gas field, which is a high salinity wastewater containing complex components. At present, the treatment of mother liquor is facing great difficulties with the lack of mature processing technology. This study intends to carry out advanced treatment of mother liquor. After the process comparison and optimization, the mother liquor was treated by coagulation sedimentation, sulfate removal of calcium chloride, and organic compounds removal of UV+H₂O₂ co-oxidation. The effluent quality indexes were achieved by SS<50 mg/L, sulfate radical of 4 200 mg/L and TOC of 459.25 mg/L, which can meet the requirements of influent water quality for the produced water treatment process in Yuanba gas field. Therefore, the plight of mother liquor build-up and advanced treatment would be significantly improved. The processing techniques in this study have the advantages of simple technological process and easy maintainability. To some extent, the near zero discharge of mother liquor could be achieved.