R&D Center, Samsung Engineering Co. Ltd, 415-10 Woncheon-Dong, Youngtong-Gu, Suwon, Gyeonggi-Do, 443-823, Republic of Korea.
R&D Center, Samsung Engineering Co. Ltd, 415-10 Woncheon-Dong, Youngtong-Gu, Suwon, Gyeonggi-Do, 443-823, Republic of Korea.
Water Res. 2019 Jul 1;158:411-416. doi: 10.1016/j.watres.2019.02.017. Epub 2019 Feb 19.
The removal of urea by persulfate with UV irradiation in an ultrapure water (UPW) production system was examined using a continuously operated column reactor. Urea is a substance that is not properly removed by the unit processes in UPW production systems. Based on our monitoring of urea concentration over 1 year of the operation of a UPW production facility, a relatively high concentration of urea was introduced between February and May in 2016 and the total organic carbon (TOC) concentration of the UPW was increased in that period. Approximately 50% of the urea in the raw water was removed by the UPW production process, for which double-pass reverse osmosis units were instrumental. The addition of persulfate to the TOC reduction UV unit in the UPW production process was examined to improve the efficiency of urea removal. As a result, supplying over 20 μmol/L persulfate to the TOC reduction UV reactor improved the efficiency of urea removal from 9% to 90%. UV dose was an important factor of urea removal. In the ion analysis, nitrate and sulfate were detected in the effluent, and the ratio of produced nitrate to the removed urea was approximately 2.
采用连续操作柱式反应器研究了在超纯水（UPW）生产系统中用过硫酸盐和紫外辐射去除尿素。尿素是 UPW 生产系统的单元工艺不能有效去除的物质。根据我们对 UPW 生产设施运行一年多来尿素浓度的监测，2016 年 2 月至 5 月期间，尿素的浓度相对较高，在此期间，超纯水中的总有机碳（TOC）浓度增加。大约 50%的原水中的尿素被 UPW 生产工艺去除，双级反渗透装置在其中发挥了重要作用。为了提高尿素去除效率，在 UPW 生产过程的 TOC 还原 UV 单元中添加过硫酸盐。结果表明，向 TOC 还原 UV 反应器中供应超过 20μmol/L 的过硫酸盐，可将尿素去除效率从 9%提高到 90%。紫外剂量是尿素去除的一个重要因素。在离子分析中，在流出物中检测到硝酸盐和硫酸盐，生成的硝酸盐与去除的尿素的比例约为 2。
