Summary
• Thrifty Firewood Co is using greenheart dust and shavings to make briquettes.
• The dust and shavings are converted in a Weima TH520 briquette press supplied by Weima UK,a division of Fercell Engineering.
• Thrifty Firewood could produce more than 6,720, 10kg sacks of briquettes a year.

A frugal Yorkshireman is using high calorific value waste to bring an innovative product to the wood fuel market.

Martin Larkin of the Thrifty Firewood Co, Cleckheaton, uses greenheart sawdust and shavings for his high-quality briquettes, which he says burn hotter than many kinds of coal.

His new venture completes a chain of greenheart utilisation that does not leave a scrap of waste. Virgin and salvaged timber is used in the construction of breakwaters, bridges and oil rigs, offcuts and seconds are fashioned into 8in-long bale skewers for the wool industry, and factory waste is compressed into briquettes for the domestic wood burner market.

Raw material

Woodworker and hardwood and speciality timber merchant Mr Larkin is making the most of a free raw material and greenheart’s extraordinary calorific value. “Animal bedding isn’t a good recycling option for hardwood as it can cause respiratory problems,” he said. “And I had the idea that a briquette machine would not only provide me with a solution for my own hardwood waste disposal, but also give me the option to take other people’s waste, saving on their disposal cost and, when processed, creating a saleable product.

“Because of the nature of the building trade, work can quieten down in winter. I also envisaged extra income and extra work from processing the waste into fuel. It’s a seasonal, sustainable job for me.”

Mr Larkin regularly now collects half-tonne loads of dust and shavings from the skewer factory just down the road and blends it with waste from his own operation and from customers and neighbouring businesses. The mix is then run through a TH520 briquette press from Weima of Germany.

Hydraulic pressure and binding agents already present in the wood mean there is no need for binders or resin, as long as moisture content remains below 18% and chip size is constant. The end product is very dense and burns with a surprisingly intense heat.

Production capacity

The Weima press is billed as capable of processing up to 8,200kg per hour and, based on an input of 10m3 of wood waste, weighing an estimated 1,400kg, and a running time of 14 hours each week, Weima’s UK agent Fercell Engineering Ltd predicted that Mr Larkin could produce 6,720, 10kg sacks of briquettes per year. If he sells them at £3.50 per sack, it said, he could achieve annual revenue of £23,520.

Mr Larkin said he is already exceeding his production targets and, while he stockpiles briquettes in preparation for a marketing push this winter, he is investigating alternative sources of wood waste.

“I’m letting small businesses know they can save on their waste disposal expenditure by allowing me to collect their wood waste,” he said. “One man was paying for his bin to be emptied every month – now he saves money and I make money. It’s a win-win situation.”

He is working to make the operation as clean as possible. Health and safety concerns include potential severe throat irritation from greenheart dust, which when in sand flour form can remain in the lung. Because of their strength, greenheart splinters are also more likely to puncture the skin than most woods, and more likely to become septic.

Buoyant market

Sustainable sources of greenheart offcuts and seconds show no sign of waning. The market for the species is buoyant, unlike the wood itself, which is so dense it sinks in water.

Greenheart is grown almost exclusively in Guyana, South America, where nearly 60% of the country is state forest – home to over 120 species of tree. Greenheart is grown in clumps rather than plantations and the Guyana Forestry Commission awards harvesting licences.

Marine and construction timber specialist Aitken & Howard, a UK importer of greenheart and one of Mr Larkin’s suppliers, has no fears over sustainability of supply.

“There is natural regeneration over three or four generations,” said a spokesperson. “The forestry should go on forever, it’s very carefully managed and we have complete chain of custody.” He also predicts salvage sources will remain stable as new greenheart clumps are established and disused and damaged timbers are gradually reclaimed.

Meanwhile Mr Larkin says the market for wood fuel is increasing and likely to carry on growing.

“Wood recycling solves waste and fuel issues in one fell swoop,” he said. “It’s bringing manufacturing jobs to Cleckheaton and helping the town become more self-sufficient. Recycling is where the new world meets the old.”