焦化尾水资源化回用集成工艺中试OA北大核心CSTPCD

To achieve the resource reuse of coking tail water,an integrated process,incorporating pretreatment,pressure-and electrically-driven membrane coupled process,and bipolar membrane electrodialysis,has been devised and piloted.In the integrated process,chemical softening and ozone-hydrogen peroxide composite oxidation process removed hardness and organics.The nanofiltration process separated ions.The electrodialysis and bipolar membrane electrodialysis processes achieve near-zero discharge and acid-base recycling.The chemical softening process can remove up to 64.2%of the hardness in raw water.The ozone-hydrogen peroxide composite oxidation process can remove up to 35.0%of the COD in reverse osmosis concentrated water.The nanofiltration process can achieve a desalination rate of 30.2%,with removal rates of chlorine ions,sulfate radicals,hardness,and TOC of-6.8%,97.3%,78.4%,and 87.4%,respectively.The bipolar membrane electrodialysis process can obtain acids and bases with concentrations above 2 mol/L,with an energy consumption of 4.0 kW·h/kg.The water reuse rate of this integrated process exceeds 90%.Acids and bases can be recycled in a short-term cycle.