Bleach Plant Pressate Cooling

Catalyst Paper Corporation
Powell River, British Columbia
Project Year: 2007

This project involved relocating two obsolete shell and tube heat exchangers removed from the shut down kraft mill, and an automatic water filter removed from the upper floor of the old groundwood screen room. The equipment was then installed onto new concrete foundations and a new steel frame/platform arrangement in the old groundwood screen room area basement.
Warm temperatures the previous summer resulted in effluent temperatures becoming too high for the biological component of the treatment system to survive. Excess pressate from the bleach plant is now diverted to the heat exchangers and cooled using filtered mill water before being sent to the effluent treatment system. Additionally, a future tie-in point was added to reclaim heated mill water back into the process, and to route cooled pressate back into the white water chest to help with temperature control in the winter months.

All of the equipment, valves, and some of the stainless steel piping was existing mill site surplus. Minimal new purchased materials were required.

The project included budget preparation, along with detailed process, structural, and mechanical engineering and design.