Chain Grate Biomass Fired Steam Boiler
Working pressure: 1.0-2.5 MPA
Available fuel: Biomass particles (Rice husk, straw, coffee husk, sawdust, bagasse, etc.)
Available industries: Heating, chemical, food, tobacco, textile, printing and dyeing, feed, medicine, building material, wine, rubber, hospital
Biomass Fired Steam Boiler Applicable Fuel
DZL type biomass steam boiler adopts chain grate, suitable fuel for molding pellet fuel, can add a small amount of wood, wood block, can also be mixed with coal.
Biomass Fired Steam Boiler Introduction
The chain grate biomass fired steam boiler is a kind of horizontal three-return water and fire tube mixed boiler, which has a bunch of threaded smoke pipe arranged in the boiler barrel. The left and right sides of the furnace chamber are equipped with water cooling walls of light pipes. Chain grate is adopted to realize mechanical coal feeding, equipped with blower and induced draft fan for mechanical ventilation, and equipped with scraper type slag discharge machine to realize automatic slag discharge. The front and rear arches of the furnace adopt new energy saving technology. After the fuel falls on the grate from the coal sill and enters the furnace for combustion, the flame, through the refraction of the rear arch, turns upward through the burning Chambers on both sides of the body and turns to the front smoke box, and then turns back to the tube bundle in the pot by the front smoke box, enters the economizer through the rear smoke box, and then is pumped by the induced draft fan to the air through the flue to the chimney.
Biomass Fired Steam Boiler Structure Feature
- The pot barrel is composed of arched tube plate and threaded smoke pipe, so that the pot barrel changes from a quasi-rigid body to a quasi-elastic body structure, and the stretch parts in the tube plate area are eliminated to reduce the stress. The smoke pipe in the tube plate is changed from two return journey to single return journey, which solves the problem of crack in the tube plate.
- The bottom of the pot is arranged with an ascending pipe row, which eliminates the stagnant area at the bottom of the pot and makes the mud residue not easy to deposit. The high temperature area of the pot can be well cooled to prevent the bottom bulge of the pot.
- High efficiency heat transfer threaded smoke pipe is adopted to enhance the heat transfer effect and achieve the characteristics of boiler heating up and boosting fast, thus improving the thermal efficiency of the boiler.
- Compact structure, compared with the same type of boiler, small external size, saving investment in boiler house infrastructure.
- Stable operation, convenient adjustment and sufficient output.
- The use of threaded smoke pipe to enhance heat transfer, improve the heat transfer coefficient and thermal efficiency, because the smoke in the pipe has a disturbance. Smoke tube is not easy to accumulate ash, play the role of cleaning.
- The eight-character wall in the furnace and the smoke window at the exit have a certain dust-lowering effect. The original dust concentration of the boiler is controlled below the standard to ensure that the soot emission of the boiler can meet the target of environmental protection regulation.
- The unique double-layer secondary air design improves the ignition condition of biomass fuel, adopts independent air chamber, achieves reasonable distribution of air, forms an aerodynamic field conducive to combustion in the furnace, and makes the combustion temperature and combustion efficiency high.
Biomass Fired Steam Boiler Performance
- Simulated controlled combustion can be achieved without deflagration;
- The ignition rate of combustion can be controlled by adjusting the secondary air volume of speed control;
- Secondary air is arranged in front and rear arches to ensure secondary combustion of fly ash after particle decomposition with high combustion efficiency;
- Adopt chain grate and mechanical feeding. Uniform feed, stable combustion, convenient control, with non – tempering, convenient mechanical ash cleaning.
Biomass Fired Steam Boiler Working Process
The coal with roughly uniform biomass particles falls into the coal sill by the automatic coal loader and enters the front arch for preheating under the rotation of the chain grate. It burns out in the burning area and falls into the slag pool. The high-temperature flue gas generated by furnace combustion enters the back of the furnace through the arch mouth at the lower part of the two-wing flue, and then carries out heat transfer through the two-wing flue, flows forward through the front smoke box, enters the convection tube after heat transfer, enters the economizer and dust collector at the end of the pot, and is sent to the chimney through the induced draft fan, and discharged into the atmosphere.
The boiler feed water is completed by the boiler feed water pump, the softened water by the feed water economizer, and then into the pot barrel, and then into the left and right header by the drop pipe. The water cooling walls on both sides absorb heat and vaporize to generate steam. The steam enters the steam separator in the pot and enters the heat flow through the main steam valve after separation.
Biomass Moulding Fuel Description
Biomass Moulding Fuel, “BMF” for short., is the use of agricultural and forestry waste (such as straw, sawdust, bagasse, etc.) as raw materials, after grinding, drying, mixing, extrusion and other technological processes, made of molding (such as granular, bar, block, etc.) fuel. Mainly used to replace the traditional fossil energy (coal, oil, natural gas), in the specially developed biomass combustion machine in direct combustion of a new clean fuel.
BMF is composed of combustible, inorganic and water, mainly containing carbon (C), hydrogen (H), oxygen (O) and a small amount of nitrogen (N), sulfur (S) and other elements, and contains ash and water. The components are as follows:
- Carbon: BMF fuel is a low-carbon fuel with low carbon content (about 45-50%), especially low fixed carbon content (about 16%), so the carbon emission during combustion is low.
- Hydrogen: BMF fuel is rich in hydrogen (about 5-8%) and has high volatile content (more than 70%), so it has good combustion characteristics.
- Oxygen: BMF fuel has high oxygen content (about 35-40%). The oxygen content of biomass fuel is significantly higher than that of mineral coal, which makes biomass fuel easy to ignite.
- Sulfur: BMF fuel contains less than 0.08% sulfur and has good environmental protection characteristics. It is unnecessary to set up flue gas desulfurization device when burning.
- Ash content: High quality woody biomass is mainly used as raw material for BMF particulate fuel, and the ash content is relatively low, only 1.5-3%.
Biomass Fuel Characteristics
As a high-quality homogeneous fuel, molded fuel can be automatically controlled in transportation, storage, transmission and combustion, and its convenience is comparable to that of light fuel.
- Solid fuel, high density, small volume, safe and convenient storage, clean;
- High volatile fuel, easy ignition, good combustion characteristics, high burnout rate;
- The sulfur content is very low, only about 1/20 of that of fuel oil. It can meet the environmental protection requirements without taking any measures of desulfurization and denitrification.
- Low ash content, conventional dust removal device can meet the environmental requirements;
- “0” emissions: CO2 emitted from biomass combustion is the same as CO2 absorbed in the growth process, and it replaces fossil energy and reduces net emissions. CO2 from biomass fuel is ecological “0” emissions.
Biomass Fired Steam Boiler Specification
|Model||Rated thermal power（t/h/MW）||Rated working pressure（MPa）||Steam temperature/Rated output water temperature（℃）||Thermal efficiency（%）||Maximum transport size(m)
Leave a Reply