A DEVICE that converts household rubbish into soil nutrients is to be the first in the country to be allowed to recycle catering waste.

The aerobic digester, at Thornley Waste Transfer Station, in east Durham, was opened by Prime Minister Tony Blair in 2002.

It was the first of its kind in the country and recycles more than 8,000 tonnes of household rubbish a year into compost and other recyclable by-products.

Now it has been hailed as a model of best practice by the Department for the Environment, Food and Rural Affairs (Defra). The Government department has also granted it a licence to process catering waste and out-of-date food, which will also be turned into compost.

The £1.7m plant is owned by CDENT, a subsidiary of the County Durham Environmental Trust. It is operated by Premier Waste Management and disposes of household waste from County Durham, Darlington, South Tyneside and Sunderland. It is currently carrying out trials using municipal waste from the Easington district.

Councillor Brian Myers, cabinet member with portfolio for waste management for Durham County Council, said: "The county council is now confident that commercial scale plants can be constructed and has now provided funding for a second tower to be developed at the Thornley site.

"This will contribute to achieving a 25 per cent waste recovery rate for the county."

Scientists at Newcastle and Durham Universities are carrying out trials to see if the soil conditioner produced by the digester can be used for things such as landfill restoration or tree planting.