Energy Articles
1、 Biomass boiler concept of environmental protection:
The use of biomass fuel boilers, gas boilers, biomass gasification boiler, steam laundry to achieve life heating, heating, central air conditioning, refrigeration, heating water to supply thermal energy, replacing traditional fuel, coal boiler heating mode to achieve Grand strategy of industrial boilers, boiler living and ecological environment, energy saving. Combustion Characteristics of biomass fuel, raw material requirements and technical operating characteristics of the fuel boiler. Run economic cost accounting biomass fuel boiler. Comprehensive utilization of resources to achieve circular economy, energy conservation and increase economic benefits. surroundings. Sunrise industry of vast land, large agricultural and forestry biomass, wide coverage, adequate sources. After combustion of biomass materials rich in potassium and zinc calcium magnesium phosphate, it can be used as efficient fertilizer. Biomass in the processing there are about 5% -10% of the top and the leaves can be used as raw material for the production of feed. Straw compared with coal, a large source of wide grain every year, with an annual output of straw; straw after the harvest is used for power generation, boiler fuel, to avoid environmental pollution caused by farmers burning straw, greatly reducing greenhouse gas emission. Biomass gasification under certain thermodynamic conditions, by means of air portion (or oxygen), the role of water vapor, so that biomass pyrolyzed polymers, oxidation, reduction reforming reaction, and ultimately converted to carbon monoxide, hydrogen process and low molecular weight hydrocarbons and other combustible gases.
2、 The preamble:
The importance of biomass, the role and development trends:
Biomass is plant organic matter through photosynthesis generated, its energy comes from solar energy. Biomass is a solar energy. Biomass is the most important solar energy absorption and storage, solar energy is converted into heat energy in a way.
Biomass energy in 2003 was listed as the world's fourth-largest energy in 2004 and was listed as the third largest energy row before the oil in Europe is considered second only to the second-largest nuclear energy. Because biomass can be grown in the big field, and very environmentally friendly to use, so the developed countries have attached great importance to the research, development and application of biomass energy.
Biomass renewable energy in the series is the only way to achieve urban industrial life, a new clean energy heating, and only the manufacturing cost of the lowest storage costs of clean green energy. It features all-weather operation, unaffected by weather and night.
Biomass is considered clean energy in the world, with its unique practicality and renewable widely used. The biomass briquette, especially particulate fuel, with its own characteristics and combustion characteristics, it has replaced the industrial boiler oil, gas, coal trend. Oil, natural gas is part of the non-renewable mineral resources, mining and limited content, today the world is facing increasingly tense energy shortage situation, the face of this trend, in the past in order to solve the shortage of traditional energy sources and to develop new energy (including nuclear, wind, solar and biomass, etc.) began to re-pay attention to it, especially for such a lack of oil, but in a country of heavy industrialization stage of development, the development of new energy sources has become an important issue involving national security and sustainable economic development.
Therefore, the use of biomass fuel boilers to achieve urban industrial and domestic heating, thus replacing the traditional oil, gas, coal boiler heating mode, and apply economic analysis, the heating industry has become urgent study.
Third, the introduction and biomass fuel combustion characteristics:
3、 Biomass briquette Description:
Biomass briquette: The use of agricultural and forest products processing waste (such as wood chips, crop stalks dry, Stick, peanut shells, etc.) compression molding of fuel, its manufacturing and production can be recycled, which is characterized by: easy ignition good combustion performance, high fuel density, burnout is higher than coal, is about three times volatile coal, coal ash is about 1 / 3-1 / 7, almost zero sulfur dioxide, desulfurization can be achieved without "industrial boiler air pollution emission standards ", ash is a high-quality potash. Carbon dioxide (biomass material) of plant growth and absorb the carbon dioxide emissions from burning and other offset each other, so depending on their carbon dioxide emissions as "zero", so called "zero" new green clean energy emissions.
Biomass briquette forming technology, there are three, namely, screw and piston ram extrusion and roll style. 50 mm diameter cylindrical shape is hexagonal, square 25 × 25 mm and the diameter of the particle type 20 to 6 mm.
Our country is now the world's fastest growing economies, but also a big energy consuming country. How to achieve scientific development, to achieve environmental value is a major problem facing China. With the introduction of "new energy industry development plan" and a series of favorable policies, biomass is also thanks to the widespread development of gold, with wind and solar energy and other renewable energy development competition in the lead role of biomass increasingly prominent.
More effective development and utilization of biomass energy has a special significance for the rural areas of China, in recent years, the State Grid Corporation, five power generation groups and other large state-owned, private and foreign-funded enterprises have invested in China to participate in the construction and operation of biomass power generation industry. By the end of 2009, the national production, to carry out preparatory work in the construction of biomass power generation project has more than 170 installed capacity of 4.6 million kilowatts, of which more than 50 have been put into operation, the installed capacity of more than 100 million kilowatts. Last year the National Development and Reform Commission raised the price of agricultural and forestry biomass power generation Internet (0.75 yuan per kWh) notice and specification of biomass power generation project construction management, not only effectively alleviate the cost pressure on biomass power generation, but also solve the problem of competition for fuel, biomass power generation industry in the "five" during the large-scale development to create a good environment. Sunrise industry of vast land, large agricultural and forestry biomass, wide coverage, adequate sources. After combustion of biomass materials rich in potassium and zinc calcium magnesium phosphate, it can be used as efficient fertilizer. Biomass in the processing there are about 5% -10% of the top and the leaves can be used as raw material for the production of feed. Straw compared with coal, a large source of wide grain every year, with an annual output of straw; straw after the harvest is used for power generation, boiler fuel, to avoid environmental pollution caused by farmers burning straw, greatly reducing greenhouse gas emission.
Biomass fuel related parameters in the following table
No.
|
Content
|
Numerical
|
1
|
Dried calorific Qnet, d (kcal / kg)
|
>4300
|
2
|
Dry basis total sulfur Std (%)
|
<0.33
|
3
|
Ash dry basis (%)
|
<2.2
|
4
|
Dried basis volatile Vd (%)
|
>79
|
5
|
Dry basis fixed carbon Fcd (%)
|
>19
|
4、 Biomass pellet fuel boiler Description:
Biomass pellet fuel, the use of agricultural and forest products processing waste (such as sawdust, dry stalks, Stick, peanut shells, etc.) through the high-temperature curing, compression molding fuel. Biomass pellet fuel: With ignition easy, good fuel performance, high calorific value, high fuel density, non-polluting, combustion can meet environmental emission standards GB13271-2001 "Boiler Air Pollutants Emission Standards"; low price, this product is a kinds of energy efficient environmentally friendly thermal energy equipment. This product has a specific gravity (1.0-1.27kg / m3), high calorific value (3800-4500 kcal), combustion (total sulfur 0.44%, 7.60% moisture, 9.21% ash content, volatile ≥65.62%, the combustion rate 90 % or more), low cost, easy to use, clean and sanitary, etc., easy storage and transport.
5、 Raw biomass fuel combustion characteristics:
(1) The mechanism of combustion of biomass briquette is a static osmotic diffusion combustion, the combustion process ignition of combustible volatiles from the start of the fuel surface exothermic chemical reaction of combustible gas and oxygen to form a flame. In addition to fuel combustion surface portion of the combustible volatile matter, the surface layer portion of the carbon fuel combustion in the transition zone, a flame is formed long. Fuel surface is still less volatile combustion, and to a deeper penetration. In a layer of carbon combustion, combustion of the coke combustion to diffusion, absorption, high thermal efficiency.
(2) Since the biomass briquette is formed through the high pressure, the density is very large, slowly decomposing volatile combustion, combustion in the power zone, with the volatile combustion gradually into the transition zone and the diffusion zone. If the burn rate is moderate, it is possible to make the heat evolved volatile timely delivery to the heating surface, so that heat loss is reduced. At the same time a good match volatile oxygen diffusion of oxygen from the outside world required for combustion, volatile matter can burn, without too much added to the air, temperature gradually increased, reducing the amount of incomplete combustion gas and exhaust heat loss loss.
(3) Volatile combustion, the remaining coke skeleton compact, like coal coke skeleton, like air movement can not be suspended so that the disintegration of the skeleton, so that the carbon skeleton can keep stratified combustion, stratified charge combustion can be formed core. Then the oxygen permeation of oxygen and static diffusion combustion of carbon required considerable, sustained combustion stability, high furnace temperature, reducing the solids and heat losses can be clearly seen in the combustion process in the combustion of carbon, blue wrapped in bright color flame charcoal burning time was significantly prolonged.
In short biomass briquette burning rate even moderate, the amount of oxygen needed for combustion and outside the penetration of oxygen diffusion can better match the combustion wave reduction, combustion is relatively stable, the release of heat absorption and utilization is high.