Abstract:

In the color filter manufacturing process of thin-film transistor liquid crystal displays(TFT-LCD), a significant amount of wastewater is generated, characterized by high organic content and poor biodegradability. Before discharging into municipal wastewater treatment plants, multiple treatment processes are required for efficient purification. A high-generation TFT-LCD factory employed a combined process comprising “pH adjustment tank+coagulation tank+oxidation tank+flocculation tank+sedimentation tank+intermediate tank+two-stage A/O+secondary sedimentation tank” for color filter wastewater treatment. The wastewater treatment effectiveness of this combined process over six months of operation was investigated, and the operational costs were analyzed. The results indicated that the combined process exhibited stable removal efficiency for pollutants in water. The effluent pH, color, COD, BOD₅, NH₄ ⁺-N, TN, and TP were 7.69±0.15, (3.04±0.64) times, (72.28±6.62) mg/L, (1.83±1.50) mg/L, (0.96±0.44) mg/L, (2.07±1.11) mg/L, and (0.32±0.07) mg/L, respectively, which surpassed the Class Ⅲ criteria of the Integrated Wastewater Discharge Standard(GB 8978—1996), Grade B requirements of the Water Quality Standard for Discharge to Municipal Sewage Networks(GB/T 31962—2015), and local acceptance standards for wastewater treatment plants. The direct operating cost of this project was 4.46 yuan/m³, which had promotional value in TFT-LCD and other related industries.

Key words: thin-film transistor liquid crystal display, color filter wastewater, two-stage A/O

摘要：

薄膜晶体管液晶显示器（Thin-film transistor liquid crystal display，TFT-LCD）的彩膜制程工艺中会产生大量废水，其水质具有有机物含量高和可生化性差的特点，在排入城镇污水处理厂前，需采用多种处理工艺对其进行高效净化。某高世代TFT-LCD工厂采用“pH调节池+混凝池+氧化池+絮凝池+沉淀池+中间水池+两级A/O+二沉池”组合工艺进行彩膜废水处理，探究了该组合工艺运行6个月对废水的处理效果，并分析了运行成本。结果表明：组合工艺对水体中污染物的去除效果较稳定，出水pH、色度、COD、BOD₅、NH₄ ⁺-N、TN和TP分别为7.69±0.15、（3.04±0.64）倍、（72.28±6.62） mg/L、（1.83±1.50） mg/L、（0.96±0.44） mg/L、（2.07±1.11） mg/L和（0.32±0.07） mg/L，优于《污水综合排放标准》（GB 8978—1996）三级标准、《污水排入城镇下水道水质标准》（GB/T 31962—2015）B级标准和当地污水处理厂的纳管标准；该项目直接运行成本为4.46元/m³，在TFT-LCD以及其他相关行业里有推广价值。

关键词: 薄膜晶体管液晶显示器, 彩膜废水, 两级A/O

CLC Number: 

• X703.1