mertec

something i found on mertec.
18 April 2009 | by Technology Application of the Year 2009

Project: Meretec zinc recycling

DESPITE the benefits of recycling being well known, manufacturers continue to disregard a large volume of galvanised steel every year.

Traditionally, recycling industry practice has been to burn the zinc off the scrap metal, a costly process, both financially and environmentally.

Until now, there has been no ecologically sound or environmentally safe way to recover and recycle zinc from steel, but now a new technology at Meretec’s Ringwood plant in Melbourne has developed a way to safely process galvanised steel scrap.

The process involves adding steel to the reactor drum where hot caustic removes the coating from the steel, which is then washed and mixed with a rust inhibitor and purified. The solution is electroplated in cells where the zinc is grown and harvested. The solution is then returned via the evaporator and washed, and dried for packaging.

Once the scrap metal is loaded onto the Meretc processor, the rest of the process is entirely automated.

The hazardous waste diverted from landfill saves 10,000,000t annually and according to the company, the process results in high quality, low carbon steel scrap that is free from all contaminants and potential pollutants. Every tonne of steel de-galvanised by the system is recycled into new castings or steel, saving hundreds of kilograms of iron ore, coal, limestone and zinc.