Mitigating the risk of lead poisoning at a metal processing plant
Delivering a successful pilot system of an innovative recycling plant that reduces manual handling of metals resulting in a safer working environment
Mixed metal hand sorting raising a risk of lead poisoning for operators
The company is a manufacturer of lead products, a premium distributor of zinc and copper products and a leading supplier of metal products to the building industry throughout Ireland. It’s a division of a large pan-European engineering group. The manufacturing facility in Ireland included a lead refinery and mixed metal refinery plants and was spread over a 4.5 acre site.
For the mixed metal processing plants, the company acquires scrap metal from building site demolitions. It melts down the scrap metal to produce 8 and 3 tonne ingots, some of which are rolled into sheet coils for use in the construction industry as well as for x-ray protection in hospitals. However, contaminated materials can lie on top of the molten lead in the form of dross which needs to be disposed of. The dross although contaminated contains some mixed metals which themselves have monetary value. The company wanted to develop a better approach to processing the contaminated dross and recovering the mixed metals safely. Hand sorting can leave processing lines contaminated with lead dust which can be ingested or absorbed through the skin exposing operators to lead poisoning.
Piloting an innovative recycling solution to automate mixed metal separation
Malone Group was engaged to identify a recycling solution that could work at a large scale processing facility, reduce disposal costs and improve yield, as returns from metal recycling are low with typically 40% of waste going to landfill. The engineering team designed a pilot system to de-contaminate the mixed metal by conveying it through an agitated water bath where the water was recirculated through filters. The filtrate having a high lead content was recycled through the smelting process. The cleaned mixed materials were then conveyed for further processing to separate brass, copper and aluminium with Eddy currents. The carbon steel was removed with magnetic rollers and the remaining clean organic materials sent to the landfill.
Delivering a solution that improved yields and reduced health risks
This innovative solution reduced the amount of contaminated waste going to landfill and successfully increased the value of metals recycled from the 4 tonnes per day waste stream being processed.