How does a mechanical stoker work?
How does a mechanical stoker work?
A mechanical stoker is a mechanical system that feeds solid fuel like coal, coke or anthracite into the furnace of a steam boiler. The under feeder pushes fresh coal into the bottom of the furnace and then advances it upwards so that it mixes with the burning coal above.
What is stoker power plant?
stoker, machine for feeding coal or other solid fuel into a furnace, usually supporting the fuel during combustion. Power for running a stoker is usually furnished by an electric motor, and control of combustion is achieved by variable speed or intermittent drive.
What is chain grate stoker?
Definition of chain-grate stoker : a wide endless traveling chain that feeds and supports the fuel in a boiler furnace.
What are the principal of stokers?
Explanation: In under feed type of stokers, the fuel and air move in the same direction. In this stoker air after passing through the holes in the grate comes in contact with the raw coal. As air diffuses through the bed of raw coal, it mixes with the volatile matter generated by the raw coal.
What do you mean by stoker fired boiler?
Stoker fired boilers are the smallest units among hard coal fired boilers. They are mainly operated in local or industrial heat or heat and power generating plants. RAFAKO S.A. offers OR type steam boilers, WR type hot water boilers as well as modernisation of the existing stoker fired boilers.
What is the difference between overfeed and underfeed stoker?
Overfeed stoker is the type of stoker in which the coal is fed from the top and air is blown from below. Underfeed stoker is one where coal is fed from underneath and the air is fed from top.
What is a stoker fired boiler?
Stoker-fired boilers are used in many applications with thermal capacities below 50 MW. In these boilers, the fuel is fed by a stoker onto the grate, where it is ignited by heat from the refractory above. As the fuel travels down the grate, it continues to burn, with primary air coming from below.
What do you mean by pulverized?
1 : to reduce (as by crushing, beating, or grinding) to very small particles : atomize pulverize rock. 2 : annihilate, demolish. intransitive verb. : to become pulverized.
What type of coal is used in stoker fired boilers?
Stoker fired boilers are the smallest units among hard coal fired boilers. They are mainly operated in local or industrial heat or heat and power generating plants….Stoker fired boilers.
| Boiler type: | Natural circulation |
|---|---|
| Fuel type: | Bituminous coal |
| Net calorific value: | 23 MJ/kg |
| Additional informations: | Stoker fired boiler |
Which is the type of boiler according to firing?
A fire-tube boiler is a type of boiler in which hot gases pass from a fire through one or more tubes running through a sealed container of water. The heat of the gases is transferred through the walls of the tubes by thermal conduction, heating the water and ultimately creating steam.
What is an spreader stoker?
Spreader stokers utilize a combination of suspension burning and grate burning. The coal is continually fed into the furnace above a burning bed of coal. The coal fines are burned in suspension; the larger particles fall to the grate, where they are burned in a thin, fastburning coal bed.
What is a mechanical stoker and how does it work?
A mechanical stoker is a mechanical system that feeds solid fuel like coal, coke or anthracite into the furnace of a steam boiler. They are common on steam locomotives after 1900 and are also used on ships and power stations. Known now as a spreader stoker they remain in use today especially in furnaces fueled by wood pellets or refuse.
What is a spreader feeder and how does it work?
Spreader feeders have the capability to uniformly feed coal into a device that can propel it along the depth of a grate in an evenly distributed pattern. Many designs have been used successfully over the years. The coal feed mechanisms include gravity reciprocating plates and metering chain conveyors.
What is the maximum steam output from a stoker?
Practical considerations limit stoker size and, consequently, the maximum steam generation rates. For coal firing, this maximum is about 350,000 pounds per hour (lb/hr); for wood or other biomass firing it is about 700,000 lb/hr.
