C2764 - Pacific Coilcoaters - Colour Coaters - Auckland Region

Summary
Through a waste minimisation programme costing approximately $300,000, Pacific Coilcoaters has achieved annual after-tax savings worth more than $940,000. The main environmental benefits of the programme are more efficient use of resources, greater energy efficiency and reduced waste disposal.

Business Profile
Pacific Coilcoaters produces 30,000 tonnes of Color Cote flat painted steel roofing each year. Pacific Coilcoaters is located in Penrose, Auckland, is a member of the Fletcher group and employs 62 staff.

Type of Project
Reduced handling of coils, reduction of steel corrosion, water-cooling tower to reuse water, oil skimming from caustic baths and chemical recycling, new painting machine to reduce scrap.

Reasons for Project
High water consumption and increasing water costs.

The Project

Water cooling tower to reuse water

Details	Water is used at a rate of 11 litres per second to cool the steel after the painted surfaces have been cured in the ovens. Before Pacific Coilcoaters's CP programme was established, all this water was treated as waste after use and discarded into the sewers. Pacific Coilcoaters has now obtained approval to install a water-cooling tower, allowing the water to be reused. This will significantly reduce the company's water supply and trade waste discharge bills.
Economics	Costs for the water-cooling tower are estimated at $100,000. Savings through reduced water consumption and trade waste discharge are an estimated $70,000. The payback period is 17 months.
Benefits	Reduced water consumption and costs. Reduced trade waste discharge and costs.

Reduction of steel corrosion

Details	Pacific Coilcoaters faced a problem of corrosion caused by condensation on the cold steel in winter. To overcome this, heat from the ovens, which had previously been wasted, was pumped back into the factory to keep the steel and the rest of the factory warm. Installing the heat exchanger and overhead ducting has resulted in 70 per cent less steel corrosion.
Economics	Costs were $280,000 for the purchase and installation of the heat exchanger and overhead ducting. Annual savings are $240,000. The payback period was 14 months.
Benefits	Reduced steel corrosion. Improved product quality. Reduced steel costs.

METAL CLEANING PROCESS

Oil skimming from caustic baths and chemical recycling

Details	To prepare the steel for painting the coils are soaked in caustic soda and acid baths. The caustic soda baths were being discarded every 2-3 weeks because of contamination with oil from the coils. The company began skimming off the waste oil and storing it for separate treatment. As a result the caustic soda baths now last for 12 months. Chemicals are also recycled prolonging the life of the chemicals and significantly reducing toxic discharges.
Economics	Costs for waste oil treatment have not been determined. Total savins are approximately $33,000 per year. The payback period is 12 months.
Benefits	Reduced caustic soda consumption and costs. Reduced trade waste discharge and costs. Reduced labour time to replace caustic soda baths.

METAL FINISHING PROCESSES

New painting machine to reduce scrap

Details	A new painting machine was installed to improve the operating procedures. Scrap has been significantly reduced.
Economics	Annual savings are $243,000.
Benefits	Reduced scrap and disposal costs. Improved product quality.

For additional information contact:
Pacific Coilcoaters Ltd,
Auckland

For further information about Cleaner Production in the Metal Industry see:

Opus International Consultants (September 1997): Cleaner Production Guide for the Metal Industry- Minimising waste, reducing costs and caring for the environment.