(PRWEB) July 20, 2012
A key to slurry transport becoming more cost effective has been the development of new plastic pipeline materials that are more efficient and more resistant to the extremely harsh conditions imposed by the slurry transport process.
New PEXGOL polyethylene pipes have been approved for use in long distance slurry pipelines. These include phosphate pipelines, iron ore and magnetite pipelines, and copper and gold concentrate pipelines.
PEXGOL pipes have also been tested by Paterson & Cooke and have been found to have far better abrasion resistance than conventional HDPE pipes.
For instance, PEXGOL slurry pipes are ideal for transportation of magnetite ore concentrate from the mine site to the ship-loading berth or wharf.
The advantages of an ore slurry pipeline over truck hauling the ore overland include:
■ Fewer negative impacts on the environment and greater safety
■ Less social impact
■ Easier access for construction, operation and maintenance
■ Lower operating cost.
Furthermore, PEXGOL pipes do not need to be buried in trenches since they are UV stabilized and resistant to rock impingement damage.
These crosslinked polyethylene pipes offer extended wear life and hence lower maintenance costs. Their improved wear resistance provides increased mean time between failures.
The pipes afford longer service intervals and better pumping efficiencies at an expanded temperature range up to 114 deg.C.
PEXGOL pipes are also well suited for transport of tailings such as Taconite tailings which can be considered to be coarse sand and must be pumped in a range of speeds of 3.4–4.4 m/s to prevent settling. Conventional HDPE pipes are subject to very fast wear and are not ideal for tailings disposal. Such tailings are typically pumped at a weight concentration of 35%. The use of special flocculants and efficient thickeners allows pumping up to a weight concentration of 45%.
The functional performance properties of these PEXGOL pipes which makes them ideal for slurry pipes include:
- Superior resistance to slurry abrasion
- Prolonged wear life
- Ability to perform at much higher service temperatures than conventional HDPE pipes
- High ductility and toughness properties
- Insensitivity to slow crack growth (in contrast to conventional HDPE pipes)
- Improved cost/performance ratio over competing materials