What are the major performance features of CFBC boiler?

The major performance features of the CFBC boiler (circulating fluidizing bed combustion boiler) are: a) It has a high processing capacity because of the high gas velocity through the system.

What is a fluidized bed boiler?

Fluidized-bed boilers are the most common type of boiler recommended for biomass fuel, which is burned within a hot bed of inert particles, typically sand. The fuel-particle mix is suspended by an upward flow of combustion air within the bed. As velocities increase the gas/solid mix exhibits fluid-like properties.

What is loop seal in CFBC boiler?

In a circulating fluidized bed (CFB), the loop seal is an important component which recirculates the solids captured by the cyclone to the bottom of the riser and avoids the direct flow of gas from high-pressure riser to the low-pressure cyclone.

What is the difference between Afbc and CFBC boiler?

AFBC means atmospheric fluidized bed combustion, where the furnace pressure is atmospheric pressure. CFBC boiler stands for circulating fluidized bed combustion boiler, the furnace is pressurised and the furnace gas is recirculated to capture the unburnt carbon, to increase the thermal efficiency of the boiler.

How does a CFBC boiler work?

A circulating fluidized bed (CFB) boiler features higher gas velocity (superficial flow velocity) in the furnace (combustor) compared with a bubbling fluidized bed (BFB) boiler. The boiler activates a mixture of particles and gas to improve combustion reaction.

What is CFBC technology?

It is the boiler that uses a specific technology called ‘Circulating Fluidized Bed Combustion (CFBC)’. The high concentration of bed material along with staged air supply ensures that bulk combustion temperatures do not exceed 950°C making it environment friendly (lesser production of NOx) means of utilizing coal.

What are the advantages of a fluidized bed boiler?

The principal advantages of FBC systems include: (1) high fuel flexibility, including the capability of using fuels with a high content of sulfur or ash; (2) the capability for firing low-grade fuels, e.g., biomass, refuse-derived fuels, and wastes, and for co-firing different types of fuels; (3) in situ …

What is the function of a loop-seal?

Loop-seals are commonly used in circulating fluidized bed systems to convey particles from a low pressure region to a high pressure region. One of the principal functions of loop-seal is to avoid the undesirable inverse gas flow and to provide gas tightness.

How does a loop-seal work?

Loop-seal, considered heart of a circulating fluidized bed (CFB), returns solids captured by cyclone to the base of the riser while preventing direct flow of gas from high pressure riser to the low-pressure cyclone. For example, the minimum aeration for the onset of solids flow increases with increase in this length.