Type of CHP system: BFB boiler

Plant owner: Plant owner is Mreal Oyj

Commissioned: (reconstructed):1976 (1997)

Status of plant: Commercial

Contractor details: The main boiler of Simpele plant was commissioned by A. Ahlström Oy in 1976. Bubbling fluidised bed boiler conversion delivered by Foster Wheeler in 1997.

Power generation: Steam turbine

Main fuel: Multifuel (more biofuels and/or peat)

Typically 45% of biomass or different type of residues, 55% of peat. Heavy fuel oil is used for back-up. The moisture content of wood fuels is typically around 30-60% and for peat 45%.

Nominal capacities & efficiencies:

Thermal input, biomass & waste: 127 MW

Total thermal input, incl. fossil fuels: 127 MW

Gross electrical output: 33,6 MWe

Heat output: 113 MJ/s

Electrical efficiency, gross: 26 %

Overall efficiency, gross: 89 %

How is plant controlled: Process steam demand controls the plant operation.

Heat backup: One back-up boiler. An electric boiler will be decommissioned soon.

Heat usage: Heating and process steam

Energy usage: Process steam, 5 bar and 1 bar, supplied to paper and cardboard mill. District heat for the local energy utility Simpeleen Lämpö Oy.

Fuel storage: Wood fuels are stored on the fuel field.

Waste water: Waste water is treated in a biological sewage treatment plant.

Ash discharge: Ash is used for landscaping, also for landfilling and small amount as fertilizer.

Plant description: Plant is a multi-fuel plant. Originally it was equipped with a pf-boiler, after retrofitting using fluidised bed boiler.

Fuel feeding system: Bark from (pulp mill’s) own processes is fed through a piping system directly to the plant. There are separate intermediate storages for wood fuels and for peat.

Boiler: BFB boiler by Foster Wheeler.

Turbine: Back pressure turbine and condensing turbine.

Steam data: 40 kg/s, 525°C, 112 bar (live steam)

Flue gas cleaning: Electrostatic precipitator.

Cooling system: River water.

Staff: There are 20 persons working at the power plant.

Electricity sale info:

Electricity produced at the power plant is used in the own paper and cardboard mills. Any surplus of electricity is sold out. Condensing power is produced in order to minimise the amount of external electricity acquisition.

Total fluidised bed conversion costs were about € 10 millions (1997).

Data collected and quality assured by: VTT Processes.

Contact person: Kati Veijonen