总结文翻译

Iron and steel industry is an important basic industry of naional economy, \"important for economic competitiveness and national security “and \"one country's economic lifeline.\"

In the 21st century, China will continue to develop the blast furnace in the restructuring. F structural adjustment can not be simply summarized as Upsizing, but should be based on production scale, the reality of resources to determine the capacity of blast furnaces. In terms of the current actual situation in China, the number of blast furnace blocks must be greatly reduced while the upsizing of average furnace capacity is an inevitable trend. Large-scale blast furnace，could improve productivity, the ease of organization and management, and the quality of molten iron. it helps to reduce heat loss, energy consumption, reduce pollution point is easy to focus on pollution management, environmental protection. All of which are beneficial to reduce steel production costs and improve their market competitiveness

The graduation project is based on the original fuel conditions in Tangshan and Tangshan Steel and environmental conditions of the process, designed to produce 3.48 million tons of qualified steel blast furnace pig iron plant, and various areas of Tangshan Iron Works have many better for reference. With this graduation project deepened the understanding of the professional knowledge of the whole production process iron and steel enterprises have a more profound understanding.

The design includes the first review, the blast furnace plant design, body design of blast furnace, blast furnace plant raw material supply system, air supply system, top equipment, gas treatment system, iron slag handling system, blast furnace injection system.

Blast furnace is a natural high-grade ore, sinter, iron pellets as the main raw materials, coke as the primary fuel and reducing agent, and pulverized coal injection, natural gas and so on. Limestone as a flux slagging, blast furnace gas and the charge of the counter within the movement to complete various physical and chemical reactions. The charge temperature, soft melting, dripping, slagging, get liquid interface reaction of iron slag iron.

Blast furnace equipment in addition to the in vitro, as well as the following system: Feeding system: including storage mines, coke warehouse, storage tank mine, weighing hopper, skip pit.

Gas Purification System: generally refers to the increase in gas pipe, down pipe, scrubbers, gravity filter, venturi tubes, etc., there is high pressure valve high pressure blast furnace operation. Its role is to dust high into the raw gas purification meet the

requirements of the gas fuel.

Air supply system: including stove, heat register, air pipe, air Explorer and so on. Its role is to bring the cold air into the furnace blower.

Iron slag system: including, inter Iron Works, mud soaked, blast furnace cranes, hot metal ladle, slag pot, blocking Java machine, and blast furnace slag pool water of the hydraulic slag equipment.

To achieve high quality, low cost, high yield and extend the furnace, blast furnace body structure and support system must meet the high temperature, high pressure resistance, corrosion resistance, good sealing, reliable, long life, product quality, high output, low consumption requirements . Has become a highly mechanized modern blast furnace, a large-scale automation and comprehensive production equipment. Blast workshop design must also meet the economic and technical indicators of blast furnaces in order to achieve optimal production efficiency.

Blast furnace production of major economic indicators, including the effective volumetric rate, coke, coal than the smelting intensity, burning intensity, off-air ratio, the passing rate of pig iron, blast furnace generation of life, the cost of pig iron. Development trends of modern blast furnace (1) large-scale (2) efficient production

1) Concentrate; 2) high air temperature; 3) high pressure operation; 4) injection of fuel and oxygen-enriched blast; 5) blast humidification and dehumidification; 6) to improve the recycling and efficient use of gas. (3) blast furnace production automation 1) Top loading automation; 2) The stove automatic operation; 3) PCI Automation;

4), furnace temperature, gas composition testing automation throat. (4) to strengthen environmental protection efforts 1) efficient recycling of iron dust, carbon;

2) reducing emissions, waste, waste water emissions; 3) reduction of thermal radiation; 4) to reduce noise pollution.

This design uses the new technologies, including bell-less top and belt, cloth rotating chute fabric to achieve a variety of ways, stove with cone sphere is conducive

to the vault to improve air distribution and air temperature, partition between the increase Heat regenerator gas to prevent short-circuit plate.

Comparison site to do more programs to determine and select the best persons, site selection is reasonable or not, not only affect the speed of construction and investment, also affect the cost of the product after production and economic benefits must be very careful.

Construction of blast furnace ironmaking plant a few blocks, it is necessary to consider increasing the furnace capacity, but also consider the company's gas balance and the balance of the amount of pig iron, it is generally based on plant size, the composition of blast furnace by the two or three appropriate.

Blast of blocks from two considerations, one from the investment, productivity, management, and other considerations, the number of as little as possible; the other hand from the hot metal supply, the supply of blast furnace gas into account, we hope more numbers. Block number of principles should be established to ensure that blast in a blast furnace shutdown, the hot metal and the gas supply is not to break. New business only 2 ~ 3 blast furnace.

Blast furnace plant layout relates to the reasonableness of the adjacent workshop and public facilities is reasonable, but also to transport raw materials and products can be normal, sharing of facilities and transportation lines, the length of pipe line, the cost of product and unit investment products to some extent. Therefore, when planning workshop layout must be considerate.

Blast furnace body including the foundation, steel structure, lining and cooling equipment, and blast furnace design. The size of the blast furnace effective volume that the effective volume of blast furnace and blast furnace blast furnace plant of blocks that the scale of blast furnace blast furnace design is the body design. Modern blast furnace towards the development of large-scale horizontal. Blast advanced body structure design and reasonable is to achieve high-quality, low cost, high yield and longevity of the pre-conditions, but also blast auxiliary systems design and selection basis.

Blast is a shaft furnace, blast furnace working space within the shape of the profile, or blast furnace known as the blast furnace type. The essence of blast furnace gas flow rise and fall of the charge and mass transfer between the process, it must provide space for fuel combustion to provide the blast furnace gas mass flow and the space charge. Blast furnace fuel to meet the conditions of the original request, to provide

anterograde smelting process.

Five-phase blast as: furnace pipe, hearth staves, waist, belly stove, hearth.

Blast furnace blast furnace design is based on units of pig iron production, blast furnace with production to determine the effective volume is based on the effective volume to calculate the other dimensions.

Content of blast furnace lining design is to select each part of lining material, to determine the thickness of lining, that masonry methods and materials calculations. Lining of blast furnace design can extend the life of a reasonable and good technical and economic indicators.

Lining designed to test rate to the following three points: the working conditions of blast furnace and its various parts breakage mechanism; cooling equipment in the form and the role of lining brick; to predict erosion of the furnace is reasonable. Blast furnace blast furnace cooling equipment is an important part of the structure, life on the furnace body can play the following role: to protect the furnace shell, the cooling of the refractory and support, to maintain a reasonable operating furnace, when most or all of the refractory erosion, to the cooling device by holding blast furnace slag Peavy.

According to different parts of the working conditions of blast furnace and cooling requirements, cooling medium used is different, commonly used in the cooling medium are: water, air, and soda mixture that is water-cooled, air cooled, and evaporative cooling.

Cooling equipment work system, control and development of the cooling water flow, velocity, pressure, and poor access to water temperature. Blast furnace heat load of the different parts, different forms of cooling equipment, cooling equipment work system is also different.

Blast furnace steel structure including shell, furnace frame, steel blast furnace top platform and ladder is important to ensure normal production blast furnace facilities. Design of blast furnace steel body, mainly to solve the roof load, the load transfer to the furnace furnace stack-based ways and means, and to solve the furnace shell seals. Steel blast furnace body mainly in the following forms: hearth strut, strut body hearth furnace, furnace frame, free-standing.

Blast furnace shell is the shell, which has cooling equipment and lining, top up with loading equipment and gas pipes, located in the lower part of blast furnace based on a range of cylinder section. The main function of the furnace shell is fixed cooling

equipment to ensure a solid brick of the furnace, the furnace under pressure and play a role in sealing the furnace, and some also bear the roof load and play the role of the cooling liner, dimensionless furnace shell must have a certain strength.

Is based on the lower part of blast furnace load-bearing structure, its role is to blast all the load evenly delivered to the foundation. Buried in the ground by the blast furnace based on the base and the pier on the ground-based components.

Blast furnace plant raw material supply system includes storage tanks and storage coke tank mine design, slots, slot under the equipment and parameter determination of capacity on the feeder belt OK.

Mine the volume of storage tank can store about 12 to 18 hours of ore, coke 6 to 8 hours. After the storage tank mine blast furnace and coke storage tank is used to accept and store charge of. Furthermore, it should set some number of miscellaneous mine shafts, in order to charge the storage flux and washing equipment and other material on the tank car loading material and the belt are two kinds of belt material used in this design. Trough under the equipment and parameters, including feeder, screening equipment, tank weighing under the Transport and Charge. The design uses a belt conveyor feeding means, electronic weighing hopper weighing.

Air supply system, including blast furnace blower, cold air pipe, stove, hot air pipes and pipe all the way

Types of valves. Hot air into the blast furnace of heat about a quarter of total calories, the current blast temperature is generally 1000 ~ 1200 ℃, up to 1400 ℃, improve the air temperature is an important means to reduce the coke rate, but also conducive to increased coal injection volume.

Air supply system including the furnace blower, blast furnace hot stove. Blast furnace blower to provide oxygen necessary for fuel, hot air generated by burning coke in the gas outlet, but also provide the air pressure in the blower can be overcome under the roof material discharged from the column resistance. Designed according to the calculated effective volume of blast furnace hot stove the size of each part. Hot air furnace equipment including: stove body, burners, combustion fan, stove flue, chimney and various pipes and valves.

The design of each block is equipped with four internal combustion stove blast, four hot air furnace uses a shaped arrangement.

Top Top design includes the basic structure, fabric approach, the basic parameters of calculation. This design uses and tank bell-less top - rotate chute fabric.

Bell-less top and the main tank by the material from the hopper, weighing material tank, the center pipes, gas-tight box, rotating distribution chute, sealing the valve, discharge valve.

The design uses a rotating cloth fabric when rotating the main distributor, Vice motor also start chute at a constant speed rotation, while also making gradual chute angle radial motion, so that the formation of adjustable helical charge distribution. When the chute angle of rotation changes in fabric, the use of transition from outside to inside. This cloth can charge way to the stove pipe cross-section cloth on any part of, and may be adjusted according to the thickness of material to get more flat material surface. Calculation of basic parameters, including the length of discharge around the mouth, the mouth of the discharge flow area, hydraulic radius of the discharge opening, cutting speed, discharge rate, time of each fabric, each fabric layer calculations.

Blast furnace process, eliminate a lot of smoke from the roof, per ton of pig iron production of about 1,800 standard cubic meters of gas, which contains 20 to 24%, about 2%, 0.5%, calorific value of about 3500, it has some use of blast furnace gas value. Discharged from the blast furnace top gas, the temperature of 150 to 300, standard state when the dust contains about 40 to 100, after the removal to be cool to use.

Gas treatment system design includes the raw gas pipeline, the choice of dust removal system and determine the size of major equipment.

Blast furnace gas from the furnace top cover plate (burner) leads, the export pipe, up pipe, down pipe into the dust.

The design of blast furnace gas dust removal processing of gravity and a text, the second paper dust removal equipment; blast furnace dust bag are used; hopper funnel, with a dust bag screening at

The design of the coarse dust removal device is gravity. Semi-fine dust collector device located in the thick dust, the dust can not be used to remove coarse particles settling of fine dust, fine dust removal device to reduce the load. Semi-fine dust can be reduced to dust content gas standard state of 800 or less. Semi-fine dust removal device has cultural venturi scrubber. This design uses a venturi diameter adjustment. Fine dust filter device blast furnace gas by the rough and semi-fine dust, the still contain a small amount of finer particles of dust, fine dust before they can be further used.

This design uses the venturi device as a fine dust, fine dust can after the standard state gas content of less than 10.

Blast furnace when iron dust are a large amount, so set a dust mask for dust, exhaust pipes exit the second dust, dust, and the second one the set of a bag filter dust. There are a large number of high-temperature blast furnace pig iron and slag in liquid iron from the lower part of blast furnace slag port port and release. Timely and reasonable to deal with these is to ensure the blast furnace pig iron and slag an important part of normal production. In order to improve these efforts, there must be good for the iron and slag facilities and sufficient transport capacity.

Iron slag handling system, including air platforms and cast house slag processing equipment, iron and water treatment equipment, iron channeling Tsui layout, blast furnace equipment.

Pulverized coal injection system are coal storage, coal preparation, pulverized coal injection, hot smoke and gas and other several parts.

The second part of the material balance and heat balance calculation and calculation of the composition process. In order to achieve high yield of blast furnace, high quality, low consumption, low cost and concentrate on policy must be implemented. Concentrate is the overall improvement of the quality of raw material and fuel, to reduce the coke rate and increase lay the material foundation for refining intensity. To ensure that blast furnace in high winds, high pressure, high air temperature, high load despite stable production conditions, anterograde.

The specific content of fine material can be summarized as \"high, mature, net, uniform, small, stable\" six words, in addition, attention should be paid high temperature metallurgical properties and a reasonable charge structure.

I have now with high basicity sinter and acid pellet as a reasonable charge structure. It can overcome high high basicity basicity refractory The monomer can not drop the shortcomings of the low melting temperature to avoid acidic charge, the shortcomings of the soft melting interval too wide. Play high basicity sinter and acid good metallurgical properties of high grade iron ore pellets, high strength, uniform size, reduction and good benefits. Spiking upward pressure increase the temperature, reduce the maximum pressure value, such as increased permeability of the material layer.

Key part of the process calculation burden calculation, the material balance and heat balance calculations. Calculation of the Central Plains fuel composition

ingredients is the most basic and finishing the most critical step. First adjusted to 100% of the fuel components, and then check the original contents. Set under the given conditions to calculate the composite unknown amount of ore and limestone, according to a variety of mineral proportion in the composite obtained in a variety of mineral ore quality.

Slag and the slag composition to be calculated the amount of CaO, SiO2 content, FeO content, MgO content, Al2O3 content, MnO content furnace slag S content. Check iron components which include manganese, phosphorus, carbon checking, and sulfur, silicon, iron content do not need to check.

Material balance calculations from the top gas composition by calculating the amount of wind. Top gas group to be components of H2, CO2, CO, N2, CH4.

Income to be divided into thermal heat balance and heat expenditure items. Heat source of income is exothermic oxidation of carbon,

Hot air into the heat, the physical burden of the heat, into hot slag, H2 exothermic oxidation.Exothermic thermal decomposition of expenditures by the oxide desulfurization endothermic endothermic decomposition of carbonate, water, thermal decomposition of pulverized coal injection endothermic decomposition of the free state of the water evaporation absorbs heat, the heat away hot metal, slag away, gas with take the form of heat.