The Pontiac District is located southwest of Chicago in central Illinois on the Vermillion River. The water treatment plant system serves approximately 4,500 customers and is owned and operated by Illinois American Water, an investor-owned water utility. Because the water source for the plant is the Vermillion River, the community faces variable nitrate levels influenced by regional rainfall.
The system could no longer meet nitrate removal using blending and conventional treatment, so utility engineers chose to install a permanent nitrate removal facility to properly address the fluctuating nitrate levels. Tonka Water was selected to provide their innovative Pur-IX™ ion exchange system to address this issue. The Pur-IX™ system occupies a small footprint, has the lowest salt usage and generates the lowest water waste of any ion exchange process available.
The Pur-IX™ system applies conventional ion exchange in a new, innovative configuration, allowing designers to minimize footprint while ensuring the lowest waste volume. Pur-IX™ incorporates 20 continuously operating ion exchange vessels, 14 of which are treating water in parallel, while the remaining six are being regenerated. The system continuously cycles out-of-service vessels through an efficient multi-step regeneration process, automatically returning regenerated vessels back into service. Operating in this way ensures the ion exchange resin is used to its fullest and maximum capacity, making the process the most efficient possible.
The Pur-IX™ process generates a single continuous low flow waste stream, eliminating the need for enhancements such as waste equalization, gradual “bleeding” to final discharge, large evaporative pond waste handling systems, or shock loading to POTW’s.
Proven in over 30 installations, this fully-automated system consists of twenty continuously operating small stationary ion exchange vessels piped through a single multi-port valve. The interior disc of the multi-port valve is the only moving part in the system. It momentarily indexes once every 30-60 minutes, which means it operates for less than 12 minutes per day. This innovation, combined with internal brine and rinse recycle, greatly reduces waste and salt usage; while producing high quality potable water.
The Pontiac plant is performing well, and has been exceeding expectations since commissioning. Tonka Water is proud to have assisted the community in achieving its treatment goals.