Recycling a profit from discarded garden waste

GreenComp's trommel sifts the shredded green waste to make compost. Picture: DENISE BRADLEY (Image: Archant)

They say one man's trash is another man's treasure.

And that's particularly true for a south Norfolk firm whose rapid growth is rooted in agricultural compost, made from domestic garden waste.

Greencomp, based at the former Second World War airfield at Hethel, has agreements with four councils to dispose of the green waste left in kerb-side brown bins, or collected from recycling centres.

After securing the necessary licences four years ago, the company turned the shredded remains of discarded hedge trimmings, branches and grass cuttings into 100 tonnes of nutrient-rich compost to be used by farmers and horticultural growers.

This year, the annual output is expected to top 15,000 tonnes – a measure of the expansion of a company whose turnover now stands at £400,000, employing six people.

Greencomp was founded by partners Ian Thurtle, who was previously working in waste haulage, and Simon Stearn, a fourth-generation farmer whose land included half of the old Hethel airfield, within a 1,000-acre arable farming operation.

Mr Stearn credits the firm's success partly to the rising demand from councils eager to find alternatives to landfill – but also to the advantageous location.

'That has been our biggest attribute – we are using an old site, but we are geographically right next to the A11 and to the city,' he said. 'We couldn't do it from a greenfield site. It needed the concrete, so the fact that the foundation was here was a huge benefit to us. 'We are using about 40pc of the finished product ourselves on the farm. There is a big improvement in the soil nutrients, which is mainly potash, with small amounts of nitrogen and phosphate as well.'

Co-director Mr Thurtle said the main source of income was fees paid by councils to dispose of their waste, allowing the company to sell its finished product at a fraction of the cost commercial phosphate or potash fertilisers.

'This is an excellent way of recycling a council's waste product rather than it going to landfill,' he said. 'The benefit is in the cost and the carbon footprint. All of it is used in a 10-mile radius, so it has a very low carbon footprint.

'There are people doing this in Manchester and Birmingham, but they are in a muddle because they cannot get rid of the product because there is no agriculture. But here, we have the great benefit of being on a farm, and in an agricultural area.'

Greencomp's raw material comes from brown bins collected by South Norfolk Council, as well as garden waste collected from recycling centres including those in Norwich and Lowestoft.

South Norfolk Council said there was a growing demand for its fortnightly garden waste collection, with 1,772 new customers added last year, and 8213.6 tonnes collected in 2014/15 – a 49pc increase from 2011/12.

Greencomp is in talks with other local authorities to increase its compost production, and also recycles 5,000 tonnes of wood from council amenity sites into products including block boards and animal bedding.

The composting process:

Once delivered to Greencomp, the garden waste is shredded and placed into piles which are regularly turned over and tested daily for temperature – which can reach 65 to 80 degrees as biological processes break down the organic material.

To ensure full traceability, each windrow is numbered so its source, arrival date, and heat readings can be logged.

The shredder and the circular trommel used to sieve the fine compost from the oversized pieces represent a combined machinery investment of £500,000.

After eight weeks, the compost is ready to be sold to growers.

The entire site is surrounded by a concrete bund, with rain water and run-off diverted into a sealed lagoon, in order to meet strict environmental legislation.