A simple solution provides a big impact in a power plant demineralizer system

A large energy provider in North America experienced capacity issues at one of their coal fired generation facilities. The problem was occurring in both their anion and cation vessels within a make-up water demineralizer system. The plant had traditional counter-flow ion exchange units with water hold-down. Typically, this type of system results in less leakage and excellent quality of produced demineralized water. However, despite the large amount of acid and caustic the operators used in their regeneration process, the system was still experiencing short run times and wasting a lot of water through long, inefficient regenerations.

The company initially reached out to a consultant to help troubleshoot, but they didn’t have confidence in the proposed solution.

The plant was in the home town of one of Purolite’s Sales Managers, and he called on the facility regularly—though they were not a direct customer. At the time, Purolite provided replacement resin at the location through a third-party supplier. Despite this, the plant manager had Purolite’s contact information on file from the calls and visits made to the plant over the years and he called Purolite directly.

During the initial conversation, the plant contact explained the capacity issue. Mechanical issues were suspected as the primary cause, and our team felt it was a good opportunity to conduct a PuroPASS™ Performance Analysis System Survey to investigate further.

In the PuroPASS process, a Purolite technical service team goes on site for a customized and comprehensive evaluation of the ion exchange system. The evaluation includes:

  • System inspection

  • Regeneration sequence audit

  • Cost performance model preparation

  • Customized action plan

  • Outline of potential operating cost savings

  • Full system analysis and presentation

  • Troubleshooting of operating issues

During the system inspection, it was discovered that the central collector laterals were not sufficiently covered with resin. If not properly covered, the resin bed is not held down properly during regeneration and the bed can fluidize. This, in turn, results in poor regenerant chemical flow distribution through the resin bed and can result in un-regenerated resin or hide-out of regenerant chemicals, leading to long rinse downs and lower run times.

We suggested covering the central lateral with 6” of resin to make the hold-down flow effective and keep the regeneration zone at the bottom of the bed to prevent breakthrough leakage. Purolite also provided some additional system recommendations, which included a training class on ion exchange for their operator team on resin function and troubleshooting.

Solutions don’t have to be time consuming and expensive. The evaluation quickly identified a major system problem and provided a simple solution. Additionally, the customer developed a better understanding of their system configuration and how to effectively operate it to maintain quality and predictable performance in the future.

Why Purolite?

  • Local support team

  • Strong technical and system knowledge

  • Honest, straightforward recommendations