Abstract
A two-stage brine purification process involving an ion exchange column and a secondary filter is an important process unit in a chlor-alkali plant. As part of the effort to increase the plant capacity, the throughput of this process has been increased, which has subsequently caused non-conformance to the production specifications unless the filter is changed more frequently. Investigations are then carried out to study the sensitivity of potential variables to be manipulated in order to optimise the process, and increase the filter life. The results obtained from plant tests show that by increasing Calcium to Magnesium ratio, and maintaining lower excess sulphate the filter life can be increased. Based on these findings, a recycle stream is introduced and better performance is obtained. Following this modification, better performance is obtained, however, due to some production issues, the target desired improvement level is not ach
