Chris Franklin, MD at Ranheat Engineering Ltd – a leading UK manufacturer of wood combustion equipment – continues his series of articles for Furniture & Joinery Production.

This issue, Chris examines how the Government is looking at pollution caused by wood-burning stoves and its potentially serious effects on the UK woodworking Industry.

DEFRA published a “practical guide “to open fires and wood-burning stoves” last year. HETAS has also stated that the Government has confirmed there will be no ban on wood stoves. 

Domestic wood-burning stoves are reportedly responsible for up to 20% of air-borne pollution in the form of NOx and particulate.

Industrial users using wood waste to heat their factories are already governed by strict rules, but it is expected that these rules will change, with the emission levels lowered. The strict emission limits that apply to systems over 90kgs/hour wood consumption do not apply below the 90kg limit, but this is set to change.

The Government’s Renewable Heat incentive started with a higher emission level for NOx and Particulate. This was changed, and the limits were lowered during the scheme. At the end of the scheme, this had fallen to 30 g/GJ PM and 150 g/GJ NOx for industrial boiler systems.

Ranheat ceramic filters have been consistently measured at an average of 1.2 g/GJ particulate and 110 g/GJ for NOx.

The proposed new limits for domestic stoves will be a maximum of 375 g/GJ particulate. The current regulations look set to drop to a more stringent 185g/GJ. If the Government is targeting domestic wood-burners, it is highly likely that these will be applied to industrial installations, even small ones. 

Therefore, it is likely that new hand-loaded industrial heaters will need to be lower than this new limit. At the moment, hand-loaded industrial heaters are generally required to meet the Clean Air Act and have been exemption tested by the Government. Many of these tests were carried out more than 20 years ago. 

The feeling is that the new, stricter limits will apply to all new industrial installations. It is unlikely that a natural draft system will meet the new lower limits, as there is insufficient control with a natural draft chimney.

All Ranheat systems are fitted with induced draft (electric chimney fan) and forced draft fans for both primary and secondary air. The fans are controlled by Flue gas temperature and Ranheat warm air heaters all feature multitube heat exchangers. These multitube heat exchangers produce lower flue temperatures and higher efficiencies.

  Any Ranheat system, or indeed any wood-fired installation using waste wood, must still meet all of the current regulations. You still are legally required to obtain planning, chimney height approval and permits to enable you to legally burn wood-waste. This can be in the form of an exemption from the EA for up to 50kgs per hour, or a permit for a SWIP or a full part B permit. Ranheat is on hand to give free assistance with obtaining these permits and permissions.

For further information on all types and sizes of Industrial Woodburning equipment from 75kW upwards, contact Ranheat.

01604 750005