Combination of photocatalysis and A/O MBR for TFT-LCD organic wastewater treatment

• Main Authors: Yu-Pu Chen, 陳昱溥
• Other Authors: Sheng-Jie You
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/16658672518939339850

碩士 === 中原大學 === 土木工程研究所 === 99 === In this work, photocatalytic membrane reactor and A/O membrane bioreactor (A/O MBR) was applied for the treatment of organic wastewater from electro-optical industry. In addition, the treatment efficiency of carbon and nitrogen containing wastewater were discussed. In this experiment of photocatalytic membrane reactor, the operational parameters were set as follows, different UV irradiation, pH value between 7~11, added amount of TiO2 (DegussaP25 TiO2) between 0~1.0 g/1. After repeated trials, the optimal operational conditions were full UV irradiation, pH vale = 11, added amount of TiO2 = 1.0 (g/1). The MEA degradation rate was 90%,93%, and 98% respectively. Different circulation ratios (0.5, 1.5, 2.5) were adopted as operational parameters for the discussion of the optimal circulation ratios for A/O MBR. A/O MBR has excellent treatment efficiency of COD, MEA, and ammonia, and the removal rate for the above mentioned organic compounds were 98%, 100%, and 100%, respectively. However, the removal efficiency of TMAH was not better. It was assumed that hydraulic retention time (HRT) was not long enough for the microorganism in water to adapt, therefore the degradation efficiency was only 38%. Under different circulation ratios, the concentration of nitrate varied significantly. The average nitrate concentration was 12 mg/l, 8 mg/l, 16 mg/l for the circulation rations of 0.5, 1.5, 2.5, respectively. When the circulation ratio was 1.5, the concentration of nitrate was lower, indicating the denitrification and nitrification were more complete. Therefore the circulation ratio=1.5 was chosen as the optimal operation condition. In conclusion, the treatment of wastewaters from electro-optical industry using photocatalytic membrane reactor and A/O MBR both had better removal efficiency. As a result, the combination of chemical oxidation with biological treatment provides an anticipating solution for the undegradable and inhibitive organic wastewater generated during TFT-LCD fabrication processes.