A well designed and operated biomass boiler burning fuel within the specification of the boiler should not produce any smoke, but black smoke may be produced if the fuel is too wet for the boiler. All biomass boilers produce some oxides of nitrogen (NOx), particularly nitrogen dioxide (NO2). While NOx emissions from gas boilers have been reduced significantly in recent years through the use of low NOx burners which burn at a temperature slightly below that at which NOx forms, the nature of biomass combustion, and the need to ensure the complete combustion of wood gases, means that combustion takes place at a temperature where atmospheric oxygen and nitrogen can chemically combine. The better the quality of the combustion control system on a biomass boiler, the lower the NOx emissions will be. In general, biomass boilers produce less NOx than oil boilers. Biomass boilers do not produce any oxides of sulphur (SOx).
Woodchips are small to medium-sized pieces of wood formed by cutting or chipping larger pieces of wood such as trees, branches, logging residues, stumps, roots, and wood waste. Woodchips may be used as a biomass solid fuel and are raw material for producing wood pulp.
Although biomass-fired boilers are environment-friendly boiler products, there are also some situations that biomass-fired boilers can’t be used. Main reasons as follows:
Fuel restrictions: The fuels that contain synthetic compounds can’t be used as the fuel of a biomass-fired boiler, such as waste wood furniture, waste paper, production and domestic waste.
The main sectors in which industrial steam boilers are used are:
Food, in industrial bakeries or baby food (as an example)
Textile, in rotary dryers
Chemical, for reactors or storage
Pharmaceutical, for the manufacture of medicines
Cosmetics, for the production of perfumes and creams
Stationery and printing, in drying tunnels
The cement industry, for the manufacture of cement parts
Oil, for the storage and distribution of heavy oils
Wood, involved in the process of melanin production
Hospitals and hotels, especially in the laundry and kitchen areas
Automotive and surface treatment, for the final metal finishing.