半导体和光子工业中的制造工艺涉及使用大量的有机溶剂。这些溶剂的再循环和再利用产生馏出物残余物并且需要在排出之前进行处理。这项研究旨在评估全面废水处理厂中生物处理系统的性能,该废水处理厂处理来自电子化学品回收的含有馏出物残留物的废水。进行了批量实验,以研究全规模废水处理厂的最佳运行条件。为了实现良好的脱氮效率,出水氨和硝酸盐浓度低于20mgN/L和50mgN/L,分别,建议将进水的氨浓度和pH值分别控制在500mgN/L和8.0以下。此外,N-甲基吡咯烷酮的生物降解性,二甘醇单丁醚,和环戊酮馏出物从电子化学品制造过程中的残留物进行了好氧评估,缺氧,和厌氧条件。建议在缺氧条件下处理N-甲基吡咯烷酮和环戊酮馏出物残留物。然而,当使用环戊酮馏出物残渣作为碳源时,发生底物抑制,化学需氧量(COD)水平高于866mg/L,硝酸盐水平高于415mgN/L。在有氧条件下,N-甲基吡咯烷酮和环戊酮馏出物残留物的COD易于降解。然而,观察到对硝化的负面影响,随着初始COD浓度的增加,氨氧化的滞后时间延长。在高COD浓度下,N-甲基吡咯烷酮和环戊酮馏出物残留物的比氨氧化率和硝酸盐产率降低。此外,发现在好氧条件下二乙二醇单丁醚馏出物残渣的生物降解性很低,缺氧,和厌氧条件。关于污水处理厂脱氮微生物的丰度,结果表明,在高pH条件下,Comammox可能比氨氧化细菌具有优势。此外,Comammox可能对环境变化具有更高的抵抗力。本研究首次报道了高氨条件下Comammox对氨氧化细菌的优势。
Manufacturing processes in semiconductor and photonics industries involve the use of a significant amount of organic solvents. Recycle and reuse of these solvents produce distillate residues and require treatment before being discharged. This study aimed to evaluate the performance of the biological treatment system in a full-scale wastewater treatment plant that treats wastewater containing distillate residues from the recycling of electronic chemicals. Batch experiments were conducted to investigate the optimal operational conditions for the full-scale wastewater treatment plant. To achieve good nitrogen removal efficiency with effluent ammonia and nitrate concentrations below 20 mg N/L and 50 mg N/L, respectively, it was suggested to control the ammonia concentration and pH of the influent below 500 mg N/L and 8.0, respectively. In addition, the biodegradability of N-methylpyrrolidone, diethylene glycol monobutyl ether, and cyclopentanone distillate residues from the electronic chemicals manufacturing process were evaluated under aerobic, anoxic, and anaerobic conditions. N-methylpyrrolidone and cyclopentanone distillate residues were suggested to be treated under anoxic condition. However, substrate inhibition occurred when using cyclopentanone distillate residue as a carbon source with chemical oxygen demand (COD) levels higher than 866 mg/L and nitrate levels higher than 415 mg N/L. Under aerobic condition, the COD from both N-methylpyrrolidone and cyclopentanone distillate residues could be easily degraded. Nevertheless, a negative effect on nitrification was observed, with a prolonged lag time for ammonia oxidation as the initial COD concentration increased. The specific ammonia oxidation rate and nitrate production rate decreased under high COD concentration contributed by N-methylpyrrolidone and cyclopentanone distillate residues. Furthermore, the biodegradability of diethylene glycol monobutyl ether distillate residue was found to be low under aerobic, anoxic, and anaerobic conditions. With respect to the abundance of nitrogen removal microorganisms in the wastewater treatment plant, results showed that Comammox may have an advantage over ammonia oxidizing bacteria under high pH conditions. In addition, Comammox may have higher resistance to environmental changes. Dominance of Comammox over ammonia oxidizing bacteria under high ammonia condition was first reported in this study.