Maintenance of industrial biomass boilers

Industrial biomass boilers, whether steam, hot water or thermal oil, have special characteristics compared to fossil fuel boilers, which require certain actions to be taken to ensure their durability and correct operation.

Maintenance of industrial biomass boilers

Adjustment and control of emissions

The air emission limits for industrial biomass boilers (link with future article) are laid down for medium sized boilers (between 1 and 50 MW) in Directive 2015/2193 on the limitation of emissions of certain pollutants into the air from medium sized combustion plants.

These limits must be strictly adhered to and non-compliance may lead to the opening of a sanctioning file by the administration. It is therefore recommended that emissions be adjusted at least once a year.

Regulatory technical inspections

The industrial biomass boilers of categories I, II, III and IV according to RD 709/2015 must be subject to regulatory technical inspections as dictated by the REP (regulation of pressure equipment).

Change of grates in combustion chamber

Cast iron grates are the elements that form the combustion bed of a furnace or chamber. These grates are one of the usual consumables in an industrial biomass boiler.

The supply of cast iron grates in good condition is vital for efficient and controlled combustion. For this reason, it is advisable to have a good stock and a regular supplier who is reliable and responsive.

Refractory repairs

Refractory is the material that forms the walls of areas subjected to high temperatures such as the furnace or combustion chamber and some parts of the exchange bodies.

Its maintenance is vital to protect other materials that are less resistant to high temperatures, as well as to keep heat within the installation.

It is recommended to check the refractory parts during the maintenance checks and to repair the possible deteriorations produced.


The cleaning of the flue gas passages in biomass boilers, whether they are pyrotubular or water-tube type, is essential to guarantee the correct operation and efficiency design values of the boiler.

Likewise, the cleaning of the water, steam or thermal oil circuits is critical to guarantee the durability and guarantee of the equipment.

This cleaning can be chemical or mechanical depending on the type of dirt and incrustations adhered to the exchange bodies.

Compliance with emission standards for industrial boilers

Under the transposition of Directive 2015/2193 on the limitation of emissions into the air for medium-power boilers (between 1 and 50 MW), many biomass installations will need an upgrade in order to comply with particulate air emissions as well as NOx emissions.

These upgrades must be carried out before 2025 for installations with more than 5 MW of power and before 2030 for installations between 1 and 5 MW of power.

It is advisable to consult a specialist company to evaluate the future investment.


Subscribe to our Newsletter