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.
What is Afbc?
Acronym. Definition. AFBC. Atmospheric Fluidized-Bed Combustion (power generation, associated with coal-fired power plants)
How do I start a FBC boiler?
FBC ADVANTAGE OVER CHAIN GRATE STOKER BOILER
- Open the start up vent valve; ensure that minimum 20% MCR steam flow beacuse of maintain the flow through superheaters.
- Adjust the PA Air to wind box to start bed fluidization, ensure the air flow through windbox is above purge air flow requirement.
- Start the fuel feeders.
Why bed material is used in boiler?
The purpose of Bed Material is to support Fluidization of the Bed. It is little heavier (higher gravity) and rounded spherical shaped sand allowing uniform primary air distribution for good fluidization and at the same time ensuring excellent turbulence for combustion with minimum excess air.
What are the two parts of a boiler?
The key elements of a boiler include the burner, combustion chamber, heat exchanger, exhaust stack, and controls. Boiler accessories including the flue gas economizer are also commonly used as an effective method to recover heat from a boiler.
What are the types of boiler?
Boilers can be broadly classified as shell tube and water tube boilers.
- Shell and tube boilers. Shell and tube boilers are also referred to as fire tube or smoke tube boilers.
- Different types of fire tube boilers:
- Lancashire boiler:
- Locomotive boiler.
- Reversal Chamber:
- Wet Back Boilers:
- Dry Back Boilers:
- Two pass boilers:
What are the boiler interlocks?
Boiler interlock isn’t a physical control device. Instead it describes how the system has been wired in. It’s a wiring arrangement that prevents your boiler from heating your home when there’s no need for it, for example, if the temperature that you set on the thermostat has been reached.
What are the types of FBC boiler?
There are three basic types of fluidised bed combustion boilers: 1. Atmospheric classic Fluidised Bed Combustion System (AFBC) 2. Atmospheric circulating (fast) Fluidised Bed Combustion system(CFBC) 3.
Why clinker is formed in boiler?
Strong bonded deposits called clinkers are formed when ash deposit fuses to the furnace walls and tubes of a boiler. Due to strong bonding with the furnace walls, traditional sootblower implemented for the removal of ash deposits are ineffective for the removal of clinkers.
What is boiler efficiency formula?
Direct efficiency In order to calculate boiler efficiency by this method, we divide the total energy output of a boiler by total energy input given to the boiler, multiplied by hundred. GCV= Gross calorific value of the fuel.
What is the main function of boiler?
The main function of a boiler is to heat water to generate steam. Steam produced in a boiler can be used for a variety of purposes including space heating, sterilisation, drying, humidification and power generation.
What do you need to know about an AFBC boiler?
AFBC is atmospheric fluidised bed combustion, where the furnace pressure is atmospheric pressure. In case of CFBC, Circulating fluidised bed combustion, the furnace is pressurised and the furnace gas is recirculated to capture the unburnt carbon, to increase the thermal efficiency of the boiler.
What makes up the bed of a CFBC boiler?
The process employs bed consisting of mineral matter (ash) and coal/fuel along with limestone fluidized by combustion air .
How does an atmospheric fluidised bed combustion boiler work?
The challenge of the AFBC process is to burn fuel in an environmentally acceptable manner yet showing economic promise. The AFBC Boiler achieves this by carrying out combustion in a bed of crushed refractory / sand which is suspended by an upward stream of air, fluidising it and facilitating a significant higher degree of combustion completeness.
How is Sox control achieved in an AfBC boiler?
Due to lower operating temperatures, the AFBC boiler design is less dependent on fuel and fuel ash characteristics than conventional boilers. SOx control is achieved by limestone addition in the bed and FGD (Flue Gas Desulphurisation) is eliminated.
AFBC is atmospheric fluidised bed combustion, where the furnace pressure is atmospheric pressure. In case of CFBC, Circulating fluidised bed combustion, the furnace is pressurised and the furnace gas is recirculated to capture the unburnt carbon, to increase the thermal efficiency of the boiler.
The process employs bed consisting of mineral matter (ash) and coal/fuel along with limestone fluidized by combustion air .
What makes ZG CFBC different from other CFBC boilers?
ZG CFBC boilers are capable of burning a wide range of fuels allowing for less expensive fuel preparation and thus a reduction in costs.The solid fuel-fired CFBC boilers use internal recVirculation with two-stage solid separation system in capacities up to 680t/hr. CFBC technology evolves from AFBC to overcome some of the Problems of AFBC. d).
Why is CFBC ash recirculated in a furnace?
Note : The main reason to develop this type of combustion is to limit the emission of hazardous gases like SOx and NOx which are generated at higher bed temperatures. Source : a book on boilers for power and processes. Both are fluidized bed combustion but in cfbc ash is recirculated in furnace thereby either cooling temperature or increasing.
