Heating plants for pellets

Power categories: 500-4900 kW

Biofire’s industrial-grade pellet heating plants are suited for various types of heating needs. Due to the good calorific intensity of pellets, the storage silos are small in relation to the power category, and the refilling interval is long.

- For heat suppliers
- For municipalities
- For district heat production
- For process heating
- As maximum output plants

Heating-plant components and operational description

A system in accordance with EN303-5 standard. The fuel is stored in an appropriate silo from where it can be led to the intermediate tank inside the boiler room via a screw conveyor. The level of the tank is measured by using a capacitive sensor. Fuel flows through the shut-off feeders via the feeder screws to the combustion end of the burner (2).

Burning occurs in the combustion end and the flame is conducted inside the boiler (1.1). The automation adjusts the burning steplessly. If needed, the fuel supply and combustion-air fans react quickly to the fluctuation of power requirements by increasing or decreasing the power. The combustion air is controlled, using precise air-flow regulators and LAMBDA measurement. The heat is transferred from the boiler’s convection surfaces to the boiler water, which is kept at a consistent temperature maintained by using the PT-100 measurement.

The burned out fuel is pushed out as ash into the boiler’s ash space with the help of the hydraulically moving grate aggregate. The cyclone cleaner (9) separates the pulverized fuel ash efficiently, and the ash is then routed to ash removal. The ash is transported with screw conveyors (5) into a large ash receptacle (6) located outside the building.

The vacuum-controlled flue gas fan (7) keeps the boiler’s vacuum, i.e., draught, as desired, thus enabling the use of a wide power range.

Additional material: