Valmet’s boiler solution utilizing bubbling fluidized bed (BFB) combustion technology is called HYBEX. Wide fuel flexibility, high combustion efficiency, high reliability, excellent controllability and low emissions have turned it into a real winner, with over 200 deliveries and boiler conversions around the world.
HYBEX boilers are available in the size range of 10 to 400 MWth. Their proven technology and design ensure excellent combustion results, as well as minimal unplanned shutdowns and maintenance. With HYBEX, you can count on high combustion efficiency of over 99%, resulting in boiler efficiency typically around 90% even with high moisture fuels.
For wet and low thermal value fuels
The main advantage of the HYBEX boiler is the possibility to use fuels with high moisture content and a low thermal value. It is ideal for the following fuels:
- Wood chips
- Forest residues
- Sugarcane bagasse
- Recycled wood fuels
- Agricultural residues
- Pulp and paper mill sludge
- De-inking and water treatment sludge
Efficient control of flue gases
The BFB combustion principle is based on the fluidization of a sand bed. The hot bubbling sand and the solid fuel are mixed together in the lower part of the furnace. The high heat capacity of the sand bed ensures fast fuel ignition and absorbs fluctuations in fuel quality.
The fundamental core of the HYBEX boiler is the patented Hydro Beam grate. It enables efficient and reliable removal of impurities and coarse material from the bottom of the furnace. Over 30% of the rigid water-cooled grate construction area is open for easy removal of ash from the bottom.
Flue gas emissions are controlled with carefully designed solutions, including the combustion air system, SNCR or SCR systems, electrostatic precipitators, fabric filters with additive injection and flue gas condensing scrubbers.