Design and Construction of the Vändra 0.85 MW Boiler House

In accordance with the tender conditions and the Client’s requirements, we designed, manufactured, and built a biofuel-fired boiler house as a turnkey solution, from fuel reception to ash removal. The thermal capacity of the boiler house is 850 kW at 55% fuel moisture (nominal thermal capacity 980 kW).
The maximum operating pressure of the water boiler is 6 bar and the maximum permissible operating temperature is 110 °C.

The fuel reception capacity is >180 m³/h, and the fuel storage capacity is 230 solid m³, which corresponds to approximately one week of supply at full load operation.

The biofuel boiler is connected to the district heating network together with gas-fired peak load boilers located in a container boiler house next to the new boiler house. The container boiler house was relocated in Vändra from its original location to the new boiler house. We also implemented automatic cascade control between the three boilers.

The new biofuel boiler is designed to operate at least 8,240 operating hours per year in a capacity range of 25–100% of nominal capacity and to use wood chips with a moisture content of 35–60% as fuel. The non-heating period is intended for regular maintenance, cleaning, and repair of the equipment.

For the project, we manufactured all the main technological equipment of the boiler house – the wood chip boiler and furnace, fuel and ash conveyors, fuel reception system, moving-floor fuel storage, piping, flue gas ducts, and air ducts.