Bio-tanks to clean up wool clip

A world-beating industrial pollution treatment piloted in Timaru is winning sales in Europe and New Zealand.

The system for treating biological woolscour effluent was developed by Canterbury University doctoral student Matthew Savage at Andar-ADM Group.

Fairlie Woolscour's managing director, Brent Turnbull, said it was the most cost-effective design in the world.

Two of Mr Savage's bio-reactors, based on bacteria-filled cleaning tanks, had been sold - one to a new woolscour plant in Portugal and the other to a company in Ashburton.

Such biological treatments would be in more demand as pollution restrictions worldwide were tightened, said Mr Turnbull, especially in developing countries such as China.

Mr Savage said a woolscour plant could produce as much pollution as a small city. His treatment removed over 90 per cent of biodegradable waste and had been developed in conjunction with a chemical cleaning process at Andar-ADM Group.

The two bio-reactors, based on experimental prototypes, had sold for about $500,000, he said. A full-scale plant with both chemical and biological treatment facilities would sell for several million, depending on customer requirements.

New Zealand fleeces are usually exported untreated. Wool Board environmental technologists have been warning for several years that an Achilles' heel for the wool industry globally is the amount of effluent it produces.

The EU has already legislated to limit dip residue levels to 5 parts a million by 2006. The legislation was prompted by European scouring plants' problems in disposing of effluent heavily contaminated with insecticide.

Many farmers whose sheep produce strong wools have achieved low residue levels, and 80 per cent of the crossbred wool sent to Europe is scoured. It has hardly any pesticide left in comparison with the Australian clip, which is mostly exported in the grease.

But mid-micron growers have been shown to average around 21.7 parts a million across New Zealand, and some merino farmers in Marlborough have residue levels as high as 47 parts a million in their animals' wool, because the fine heavy fleeces hold the chemical for a long time.

Mr Savage is working towards complete removal of the waste.

- NZPA