Department of Chemical Engineering, Institut Teknologi Bandung, Jl. Ganesha 10, Bandung 40132, Indonesia E-mail:
Water Sci Technol. 2017 Jun;75(12):2891-2899. doi: 10.2166/wst.2017.173.
Electrodeionization (EDI) is the most common method to produce high purity water used for boiler feed water, microelectronic, and pharmaceutical industries. Commonly, EDI is combined with reverse osmosis (RO) to meet the requirement of EDI feed water, with hardness less than 1 ppm. However, RO requires a relatively high operating pressure and ultrafiltration (UF) as pretreatment which results in high energy consumption and high complexity in piping and instrumentation. In this work, UF was used as the sole pretreatment of EDI to produce high purity water. Tap water with conductivity 248 μS/cm was fed to UF-EDI system. The UF-EDI system showed good performance with ion removal more than 99.4% and produced water with low conductivity from 0.2 to 1 μS/cm and total organic compounds less than 0.3 ppm. Generally, product conductivity decreased with the increase of current density of EDI and the decrease of feed velocity and UF pressure. The energy consumption for UF-EDI system in this work was 0.89-2.36 kWh/m. These results proved that UF-EDI system meets the standards of high purity water for pharmaceutical and boiler feed water with lower investment and energy consumption than RO-EDI system.
电去离子（EDI）是生产锅炉给水电导率小于 1ppm 的高纯水的最常用方法，广泛应用于微电子、制药等领域。通常情况下，EDI 与反渗透（RO）结合使用以满足 EDI 进水的要求。然而，RO 需要相对较高的操作压力和超滤（UF）预处理，这导致高能耗和管道及仪器仪表复杂。在这项工作中，UF 被用作 EDI 的唯一预处理以生产高纯水。将电导率为 248μS/cm 的自来水送入 UF-EDI 系统。该 UF-EDI 系统表现出良好的性能，离子去除率超过 99.4%，产水电导率低至 0.2-1μS/cm，总有机化合物含量低于 0.3ppm。一般来说，随着 EDI 电流密度的增加、进料速度和 UF 压力的降低，产品电导率降低。本工作中 UF-EDI 系统的能耗为 0.89-2.36kWh/m³。这些结果表明，与 RO-EDI 系统相比，UF-EDI 系统具有较低的投资和能耗，可满足制药和锅炉给水电导率高的标准。
