Wes Long, Carl F. Baker
Papers # 2016 Berlin
Canfor’s Prince George Pulp & Paper Mill in Prince George, BC, Canada operates a bleach plant effluent system for the production of Bleached Kraft Pulp. The original underground fiberglass reinforced pipe (FRP) presents an elevated risk to both environment and production targets. Over the past five years there have been over 10 repairs required to maintain integrity of the pipeline. The primary objective of the project was to create a more reliable pipeline and reduce the risk of a major leak event and subsequent consequences. With temperatures up to 75°C, standard PE4710 materials were not suitable for this application. A brand new PE-RT product that expands the use of PE into larger diameter industrial applications allowing continuous operating range from -45°C to 82°C with intermittent temperatures up to 95°C was selected to replace the underground fiberglass piping.
Canfor, a producer of lumber, pulp and paper needed a solution to replace aging 30-inch (760mm) fiberglass reinforced pipe. A new PE-RT product now expands PE into industrial applications requiring resistance to high temperatures and having an HDB of 800psi at 180°F (82.2°C).
Through chemical processes, Canfor cooks, washes, and extracts pulp fiber from wood that results in both acidic and caustic effluent with temperatures normally in the 50-60°C range or as high as 70-75°C. Traditional brittle fiberglass pipes have experienced repeated joint failures over time, whereas heat-fused HDPE pipe provides solutions reducing unnecessary maintenance and a longer service life. Standard PE4710 HDPE pipes have pressure ratings limited to 140°F (60°C) and are not normally acceptable for such high temperature acidic and caustic effluent. Additionally, the potential for higher ORP’s from residual chlorine levels and bleaching also justified turning to a different material based on the potential oxidative attack at high temperatures. The new PE-RT Resin protects against oxidative attacks at high temperatures and the flexible heat-fused HDPE pipe provides considerable cost savings during installation. Compared to fiberglass, up to eight 40-foot lengths of HDPE pipe can be joined by heat fusion per day, whereas only one 6-meter length of FRP can be wrapped per day.
The presentation will highlight photos during the installation process and report the advantages of using the new pipe material. This project provides reference for expanding HDPE pipe into new applications using PE-RT materials.