| A custom-designed waste water management system is
saving Premier Plating Company $14,400 a year on the cost
of treatment and disposal of waste produced by the
electroplating process. The company has also reduced
water consumption at its plants by a massive 2.2 million
litres per year. The system cost only $15,000, so the
company’s investment has been paid back in less than
a year. The company, with a long standing concern for the environment, also values being able to reduce the volume of sludge for disposal by over 80%. |
- Irving Judge
- Premier Plating Company
- 11 Whyalla Street
- WILLETON WA 6155
- +61 9 451 5688 ph
- +61 9 457 9555 fx
Premier Plating was established as an electroplating plant in 1952 in Bently, Western Australia and now has three plants, all at the same site.
It was originally set up to electroplate tap fittings, but it has expanded and today, Premier plates in excess of three million items per year, from car bumper bars to nuts and bolts, using mainly chrome, copper, gold, nickel, silver, tin and zinc plating.
Its estimated market share is at a steady level of about 20% to 25% of the Western Australian market, with an annual turnover for 1993-94 of just under $600,000.
Premier Plating’s original electroplating process consumed around 11,000 litres of water per day - more than 4 million litres every year - and represented a major expense on the company's financial statement.
At the end of the production process, 30 different waste streams of contaminated water were discharged into four sumps behind the plant. Treatment and disposal of these wastes were complicated, labour intensive, and cost more than $1,200 per month in chemicals, equipment maintenance, waste transport, and dumping.
Different plating metals such as zinc, copper and silver produce a range of end products. Conventional chemical treatment of these end products involved the separation of the different waste and the application of specific treatment processes. The treated waste products (10% to 15% solids) were concentrated by simple settling and disposed of by methods approved by the WA Environment Protection Agency.
Dissatisfaction with this inefficient use of resources and genuine concern for the environment had motivated Premier Plating management's continuing search for a better waste management system for more than 20 years.
In early 1991, Premier Plating introduced an innovative waste management system designed by the WA-based waste water treatment specialists, ADAS Pty. Ltd..
ADAS worked with Premier Plating for two months to test and analyse the end-products in the waste water, including the alkalis, acids, chromates, heavy metals and cyanides produced through the electroplating process. Then based on the plant's existing sumps and piping systems, ADAS designed a custom-made static treatment system - the first system in Australia which treated a mixed group of end products. Premier Plating spent $15,000 - almost half-a-month’s turnover - to introduce the innovative waste water management technology.
Filtration of end-products
The new automatically controlled process involves the filtration of the end products from the waste water through a static reactor, a container filled with granules which acts as a filter. The waste water flows through the static reactor at a rate of 1,000 litres per hour and flows out in a purified form, leaving the end products inside the reactor. As static reactors are self regenerative, they automatically empty into a separate tank when the level of impurities reaches a predetermined level.
Water recycling loop
The static treatment process also involves a water recycling loop which has reduced water consumption from 11,000 litres to 1,500 litres per day. The reactor treats the effluent and sends 85% to 90% of treated water back into the factory for re-use in the rinsing process of electroplating.
The remaining 10% to 15% of treated water and regenerated end-products (sludge made up of heavy metals and chromate) are pumped into a separate tank where they are purified. The purified water is discharged to ground (with WA EPA approval), while the sludge accumulates in the tank and is removed once or twice per year to an EPA approved tipping site. This part of the process alone has resulted in a significant reduction in transport and disposal costs.
The static treatment process has provided Premier Plating with a number of benefits including:
a dramatic reduction in water consumption, estimated at 2.2 million litres per year;
lower production costs;
improved productivity;
a reduction in chemical, transport, and disposal fees, estimated at $14,400 per year;
a reduction in the amount of sludge disposed of in EPA-approved tips from 108,000 litres to 18,000 litres of sludge annually (this represents considerable savings as the EPA has introduced tipping fees of around $120 per 1,000 litres;
decreased time spent in operating and maintaining the waste water treatment system (operation and maintenance of the previous system took longer than the current two days per week).
Before After Water (litres) 2,600,000 360,000 Chemicals $2,400 $0 Waste transport $3,000 $600 Disposal $0* $2,160 Table 1. Before-and-after consumption and expenditure
Premier Plating had been dissatisfied with its previous waste water treatment system because of the massive amount of wasted water and the huge quantities of solid waste that needed to be disposed of. As water became scarcer, and as the WA EPA introduced tipping fees for sludge disposal, the company’s search for cleaner production methods became more urgent.
The technology had to be specifically designed to treat waste water with different groups of end-products.
The Cleaner Production Case Studies Directory is part of EnviroNET Australia.
For more information contact:
Environment Australia
Environment Protection Group
PO Box E305 KINGSTON ACT 2604 Email: cproduction@ea.gov.au
URL: http://www.environment.gov.au/net/environet.html