Steam Boiler Power Plant with 240 MWth Pyroflow Biomass CFB Boiler

10502025 Steam Boiler Power Plant with 240 MWth Pyroflow Biomass CFB Boiler

Sustainable, Low-Emission Biomass CHP Power Plant with Proven Operational Excellence

High-performance combined heat and power (CHP) plant with an electric capacity of 88 MVA and a thermal capacity of 240 MW. The plant is engineered for efficient and environmentally responsible operation using wood-based biomass as its primary fuel, with coal used only as a secondary support fuel under extreme moisture conditions. The plant remains in full operational service and includes all systems from biomass fuel feeding to electricity and steam dispatch. It has been exceptionally well maintained, consistently upgraded, and meets or exceeds today’s strictest environmental and quality requirements.

The steam boiler employs Circulating Fluidized Bed (CFB) combustion technology, commercial type PYROFLOW, manufactured in Finland by Ahlström in 1989. This technology ensures high-efficiency, low-emission combustion of a wide range of solid fuels—even with high variability in moisture and calorific content—making it ideal for modern, carbon-conscious operations. The CFB boiler operates with a steam flow of 100 kg/s, at 137 bar pressure and 535°C temperature. The primary fuel is wood-based biomass with a moisture content of 35–55%, ensuring carbon-neutral energy production. Coal has been used selectively during wet conditions to improve combustion balance.

The fluidized bed consists of quartz sand, with optional limestone injection for SOx control during coal operation. Emission performance remains excellent, with NOx and SOx levels well below regulatory thresholds. The boiler tubing is inspected annually, and all auxiliaries receive comprehensive servicing during scheduled maintenance outages.

The steam turbine plant is supplied by Siemens, comprising a extraction back-pressure turbine with an integrated district heating section, a condensing turbine, and an 88 MVA / 10.5 kV / 50Hz generator with auxiliaries. The 3.5 bar extraction steam is delivered to nearby industry and used to produce hot water for district heating, enabling a high-efficiency cogeneration process that minimizes energy waste and maximizes environmental value. In condensing mode, the turbine operates at full electricity output, with remaining low-pressure steam condensed efficiently in a tubular condenser.

Both turbines were refurbished to factory “zero-hour” condition by Siemens Germany in 2023. The alternator was also inspected and confirmed in excellent condition. All major maintenance and life extension work—including a comprehensive lifespan evaluation by Sumitomo in 2022—confirms over 10 years of reliable future operation.

The plant’s automation and control system was fully modernized in 2016 and now operates on Siemens T-3000 platform with Simatic S7 PLCs, enabling reliable, around-the-clock operation with automated supervision. The operators also manage a separate 120 MW auxiliary steam boiler from the same control room. Each plant features its own independent power status, boiler protection, and automation infrastructure (I/O level, processor stations, and HMI), allowing parallel or independent operation. The plant’s flexible design and digital control system contribute to enhanced operational sustainability and energy efficiency.

Here you can watch the introction videos of Siemens Steam Turbine and General Plant Introduction