某再生水厂两期脱氮除磷工艺设计及效能分析

Process Design and Efficiency Analysis of Nitrogen and Phosphorus Removal in Two Phases of a Reclaimed Water Plant

某再生水厂一期采用“7池型MSBR+反硝化生物滤池+高效气浮”工艺,二期采用“10池型MSBR+深度脱氮V型滤池”工艺,设计出水水质均要求达到地表水准Ⅳ类标准(TN≤10 mg/L)。根据2022年1月—2023年7月的运营数据,一期平均出水TN为6.50 mg/L,TP为0.16 mg/L,平均吨水电耗为0.236 kW·h/m^(3),浓度为10%的液体PAC用量为28.97 mg/L,浓度为20%的液体碳源乙酸钠用量为63.17 mg/L,运行时的平均单位污染物碳排放强度为(4.59±0.98)kgCO_(2)-eq/kg,吨水碳排放为(0.319±0.075)kgCO_(2)-eq/m^(3);二期平均出水TN为5.37 mg/L,TP为0.19 mg/L,平均吨水电耗为0.273 kW·h/m^(3),浓度为10%的液体PAC用量为42.99 mg/L,浓度为20%的液体碳源乙酸钠用量为21.98 mg/L,运行时的平均单位污染物碳排放强度为(4.75±0.67)kgCO_(2)-eq/kg,吨水碳排放为(0.328±0.050)kgCO_(2)-eq/m^(3)。

A reclaimed water plant adopts the process of 7‑tank MSBR,denitrification biological filter and high‑efficiency air flotation in phase I,and the process of 10‑tank MSBR,deep denitrification V‑type filter in phaseⅡ.The design effluent quality is required to meet level quasi‑Ⅳcriteria of Environmental Quality Standard for Surface Water(GB 3838-2002),i.e.,TN≤10 mg/L.According to relevant operation data from January 2022 to July 2023 in phaseⅠ,the average effluent TN and TP were 6.50 mg/L and 0.16 mg/L,respectively.The corresponding average unit power consumption was 0.236 kW·h/m^(3),the dosage of 10%content liquid PAC was 28.97 mg/L,and the dosage of 20%content liquid carbon source sodium acetate was 63.17 mg/L.The average carbon emission intensity per unit pollutant during operation was(4.59±0.98)kgCO_(2)-eq/kg,and the average carbon emission in tensity per ton of wastewater was(0.319±0.075)kgCO_(2)-eq/m^(3).In phaseⅡ,the average effluent TN was 5.37 mg/L,TP was 0.19 mg/L,the average unit power consumption was 0.273 kW·h/m^(3),the dosage of 10%content liquid PAC was 42.99 mg/L,and the dosage of 20%content liquid carbon source sodium acetate was 21.98 mg/L.The average unit carbon emission intensity was(4.75±0.67)kgCO_(2)-eq/kg,and the average carbon emission in tensity per ton of wastewater was(0.328±0.050)kgCO_(2)-eq/m^(3).