There are several questions asked about the use of waste wood in a boiler intended for virgin wood fuel. The rules set by OFGEM are very clear. Waste wood of any kind SHOULD NOT be used on boilers that have been accredited using virgin wood.

Problem with Recycled Fuel Fuels

There are some serious consequences for the use of waste fuel in improper and inappropriate boilers. The list below is what your waste supplier will not tell you about;

• If your RHI application for your virgin wood will be a violation of the terms for RHI and therefore you will be fined and may be required to pay your RHI payment to date.
• Your annual RHI declaration asks if you have made any changes to your fuel or system. If you say ‘No’ to your response, then this will be a breach of contract and classified as a fraud. Your RHI app can be stopped.
• The use of any waste materials as fuel (including clean A-class recycled wood waste) means you must have an Environmental Permit to do so.
• Getting enough Environmental Permission does not mean you can burn waste, just set the permitted level of air pollution. If air contaminants can not be passed through the use of filters, then you will not be able to operate the machine. Recycled waste (unlike virgin wood) produces higher levels of NOx and Sox.
• To reduce the increased particulate levels produced by using waste wood, a cyclone filter or filter filter will be required. Mesh filters can cost £ 12,000 plus per boiler for 199kW and c engines. £ 60,000 for a 1MW engine.
• CEM may also be required (Continuous Emissions Monitoring System) which tests emissions to demonstrate compliance and automatically shut down the boiler if it has to cross emission limits.
• Once the EP is obtained, and the necessary mesh filter, cyclone filter and CEM has been installed, you must reapply to OFGEM to regain accreditation. You may not be accepted into the RHI scheme or if accepted, you may be accredited at a lower rate.
• I have been audited randomly by OFGEM You must have proof of purchase of original virgin wood fuel in accordance with the kWh generated on your meter. Historical invoices, indicating the number and amount of the given BSL will be requested. Having a small pile of virgin wood in place does not qualify as ‘proof’ because it is an inadequate audit trial for the wood used.
• Your boiler guarantee is invalid and increases the damage, wear will occur so that more maintenance and increased down time.

FURTHER READING

Virgin Wood

Virgin wood comes from virgin ‘wood in round wood’, usually from the following species (douglas, pine, larch) commonly known as SPF. On the occasion of Poplar, larch, Cherry and other woods are included. This is obtained in accordance with the requirements of BS EN 14961 of forest that can be traced and managed sustainably; And often certified by accreditation bodies such as Woodsure Ltd. To be eligible for the RHI Government (payment of Renewable Heat Incentives), it must be listed in the Biomass Fuel Supplier List. Some wood fuel suppliers (such as Chip Chip Ltd) also choose to have their products and tested independently and checked and analyzed for consistency every 4 weeks by Alfred H Knight or similar; And should be monitored under an environmental management system certified by Green Dragon to level 3 or ISO 14001; Supplied by Chip Chip Limited;

Waste Wood

Once called “waste fuel” then permission is required. But there are limits, as well as some exemptions.

Plants burning less than 50kg / h do not require clearance. It’s about 135kW (chip) and 200kW (pellets). There is also a reference for 0.4MW thermal input, but this is for different parts and is an addition to the 135 / 200kW limit (from section 5.1).

The key is in defining waste. The Environment Agency has issued a briefing document (V1 September 2014) to clarify this. Broadly speaking:

– Virgin Wood is not waste

– Non-virgin wood arches, shavings, chips, sawdust are waste

– Non-treated (or non-treated) non-treated waste wood is waste. This section specifically covers any panel panel.

– Non treated virgin wood is waste

The wooden virgin is wood of:

– entire trees and wooden parts of trees including branches and bark derived from forestry products, forest management, tree operations and other similar operations (excluding clippings or ornaments consisting of leaves 2);

– virgin wood processing (eg wooden rolls, shavings or sawdust from sawmills) or wooden products dealing with virgin timber.

The Environmental Briefings document states:

“The information provided during the treatments applied to wood waste is not sufficient to ensure that all ‘clean’ grade wood is clean enough to be used for a number of purposes highlighted above and therefore we continue to classify It as” Use of waste. “Furthermore, the experience of the Environment Agency to date is such that we have no belief that the general procedure for separation of waste wood is strong enough for final use. The use of wood waste must be in accordance with the exclusion or permit Relevant. ”

Unprocessed waste wood is likely to result in higher NOx and Sox increases. This is because almost always there are nails, screws, plastics, paints, stencils, treatments, etc. In this case NOx and SOx will likely increase from virgins.

Filter requirements are driven by strict limitations on PM emissions. RHI requires only a single test that shows emissions in a limited period. EPR permissions require warranty from the filter manufacturer, otherwise the CEMs are required (Continuous Emissions Monitoring System). They also need to prove vigilantly against dust filtration equipment, which can not generally be adapted to standard reduction technologies.

It is also important to show that burnt wood will be part 1.1 or part 5.1 activity (chapters 1 and 5 of the Environmental Surface Rule, EPR). Certain fuels also exist under section 13 / 13A. EPR covers a wide range of activities. Even if permission to process waste is granted, this will be a different activity (ie, section 6.6), and therefore requires different permits or at least a variation on permits before biomass boilers can operate on waste fuel.

If there is a permit (issued with EPR for the right activity) then no RHI emission certificate (RHI-ec) is required. Permits take precedence over RHI-ec (a little bit more stringent in some ways that is slightly milder in others, yet more robust and overall weight).

The need for CEMs varies, most Binder GmbH boilers have acceptable on-board control and enough CEM for well-controlled processes. Other boiler brands may not be so.

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