CN102605125A - Blast furnace blowing rotary-wheel dehumidification method - Google Patents

Abstract

The invention relates to a blast furnace blast runner dehumidification method, which mainly includes a runner dehumidifier equipped with a runner dehumidification area and a regeneration area and capable of circulating dehumidification and then regeneration; the two sides of the runner dehumidification area are respectively provided with an inlet air duct and an outlet air duct, Regeneration air inlet duct and regeneration air outlet duct are respectively arranged on both sides of the regeneration area of the runner; the inlet air duct is equipped with an inlet air valve; the outlet duct is connected to the blower; A heater, a ventilator and a regenerating air damper are provided, and the heater steam supply pipe and the heater condensate drain pipe communicate with the heater respectively. After dehumidification by this method, the temperature of the air will rise to a certain extent, which avoids the process that the air needs to be supercooled and then reheated like the dehumidification of the surface cooler, and saves the energy consumption of reheating. High efficiency, using steam as the heat source, making full use of the steam resources of the metallurgical plant.

Description

Blast Furnace Blast Wheel Dehumidification Method

technical field

The invention relates to a dehumidification method for blast furnace ironmaking blast runners, belonging to the technical field of ironmaking blast furnaces.

Background technique

The ironmaking process is an important part of energy saving in my country's iron and steel industry. The coke ratio of key iron and steel enterprises is lower than 390kg/tFe, but some small and medium iron and steel enterprises have higher coke ratio, some even reach 488kg/tFe, and the fuel ratio is 560kg/tFe about.

Blast furnace blast dehumidification is an important measure for energy saving and consumption reduction of blast furnaces. Through blast dehumidification, blast furnace output can be increased, coal injection ratio can be increased and coke ratio can be reduced. For every 1g/m3 decrease in the moisture content of the blast furnace blast, the comprehensive coke ratio will decrease by 0.7kg/tFe, which is equivalent to 0.68kgce/tFe; Every time the moisture content decreases by 1g/m3, the production capacity of the blast furnace will increase by about 0.1% to 0.5%.

At present, blast furnace blast dehumidification is mostly used as freezing dehumidification method. The method uses a lithium bromide absorption refrigerator, utilizes waste heat steam from a steel plant as a heat source, and provides a cold source for freezing and dehumidification. The refrigeration machine takes low-temperature frozen water (generally 7°C) and sends it to the surface cooler through the water pump, and the blast air passes through the surface cooler to freeze and cool down, and precipitates moisture to achieve the effect of dehumidification. The surface cooling and freezing dehumidification method is that after the air is supercooled and dehumidified by the surface cooler, it is heated in the hot blast stove and then sent into the blast furnace, which causes energy waste and high operating costs. Lithium bromide refrigeration units need to be equipped with cooling water pumps, cooling water pumps, cooling towers and other equipment, design complex cooling water and cooling water system pipelines, and arrange special refrigeration stations, so the floor area becomes larger and the investment cost increases. The lithium bromide refrigeration unit is mainly composed of a generator, absorber, evaporator, condenser, solvent pump, and solution pump. There are many moving parts, which will generate large noise during operation, which is not conducive to the working environment of workers.

In addition, the freezing dehumidification method is suitable for occasions where the air dew point temperature is higher than 4°C, but it is not suitable for low-temperature air below 4°C. At the same time, drainage is required after freezing and dewatering, and demisting of dehumidified air is required. If the drainage is not timely, the safe operation of the fan will be affected.

Contents of the invention

The technical problem to be solved by the present invention is to provide an energy-saving and high-efficiency blast furnace blast wheel dehumidification method for the above defects, which can be used for dehumidification of air at low temperature and low humidity at -30 to +40°C, and the process is simple and takes up The floor area is small, and the running noise is small.

In order to solve the problems of the technologies described above, the technical scheme that the present invention takes:

The dehumidification method of the blast furnace blast runner uses the runner to dehumidify the low-temperature and low-humidity air. The inlet air duct and the outlet air duct are set, and the regeneration air inlet air duct and the regeneration air outlet air duct are respectively arranged on both sides of the regeneration area of the runner; heaters, ventilators and regeneration air valves are installed in sequence on the regeneration air inlet air duct , the heater steam supply pipe and the heater condensate drain pipe are respectively connected with the heater; the outdoor air enters the dehumidification area of the runner through the inlet air pipe, and the dehumidified dry air is blown into the ironmaking blast furnace; the regeneration air is sucked into the regeneration air inlet air pipe Finally, it is heated by the heater, and the heated high-temperature air enters the runner regeneration area, and the runner that has just transferred to the runner regeneration area regenerates this part of the runner for recycling, and the high-humidity hot air after passing through the runner regeneration area Exhausted to the atmosphere through the regeneration air outlet duct.

According to the above technical scheme, the inlet air duct and the regenerated air outlet air duct are not in the same direction; the inlet air duct is equipped with an inlet air valve; the outlet air duct is connected to the blower; Bypass ventilation valve; when the rotary dehumidifier is working, ensure that the bypass ventilation valve is closed.

According to the above technical scheme, the rotary wheel dehumidifier includes a casing, a filter placed in the casing, a runner and a rotary motor, and the filter is placed in front of the rotary wheel; the rotary wheel dehumidification area and the rotary wheel regeneration area are used The fan-shaped area separated by the sealing strip: the runner is set to rotate continuously under the drive of the motor and staggered in the direction of the two areas.

According to the above technical scheme, the central angle of the dehumidification area of the runner is 270°, and the central angle of the regeneration area of the runner is 90°.

According to the above technical scheme, the rotary dehumidifier adopts a lithium chloride or lithium bromide rotary dehumidifier; the rotary wheel is a lithium chloride or lithium bromide rotary wheel, and the composite material is used as the substrate and the hygroscopic material is compounded. The main components of the hygroscopic material include: Active lithium chloride or lithium bromide, and neutral silica gel, molecular sieves.

According to the above technical scheme, the regenerated air inlet duct and the regenerated air outlet duct are made of heat-resistant, moisture-resistant, non-combustible or flame-retardant materials after heat insulation treatment; 2‰, the slope faces the exit direction.

According to the above technical scheme, the heater uses steam as a heating heat source, and the steam is medium-pressure gas or low-pressure gas that has undergone temperature reduction and pressure reduction.

According to the technical scheme, the air valves are all butterfly valves.

This device is suitable for dehumidification of air under low temperature and low humidity conditions of -30 to +40 ° C, and there will be no condensation in the whole process. However, when the blast air is close to 40°C or higher than 40°C, the dehumidification effect of this device is not obvious. Therefore, this device is best suitable for areas where the summer design temperature is lower than 35°C.

Compared with the prior art, the beneficial effects of the present invention are:

Save operating costs. After the treated air is dehumidified by the runner, the temperature of the treated air will rise to a certain extent due to the conversion of latent heat of water vapor into sensible heat and the heat storage of the runner during regeneration, thus avoiding surface cooling. The air needs to go through the process of supercooling and then reheating, which saves reheating energy consumption;

The rotary dehumidification device has a large moisture absorption area, stable performance, continuous dehumidification, adjustable humidity, large dehumidification capacity, and a wide range of applicable temperatures, suitable for dehumidification of air under low temperature and low humidity conditions from -30 to +40°C;

The device is mainly composed of a box body, a runner, moisture-absorbing materials and a low-speed motor, with few components and low noise during equipment operation.

Rotary dehumidification is the most typical dry dehumidification process. The hygroscopic material in the dehumidification rotor absorbs moisture in the air and becomes crystal water instead of water solution and no condensed water is precipitated. Therefore, it will not cause safety hazards to the blast furnace blast system. question;

Compared with freezing and dehumidification, this method does not need to arrange a separate refrigeration room, which reduces the floor space and simplifies the system a lot;

The running noise of the rotary dehumidification system is also smaller than that of the refrigeration dehumidification system;

Using steam as the heat source of the refrigeration unit and heater makes full use of the existing steam heat source in the metallurgical plant, reduces the ironmaking coke ratio of the blast furnace, and provides a prerequisite for the stable production of the blast furnace.

Description of drawings

Figure 1 is a schematic diagram of the method.

In the figure: 1-filter, 2-dehumidification rotor, 3-regeneration rotor, 4-rotor motor, 5-rotor dehumidifier shell, 6-inlet air duct, 7-inlet air valve, 8-bypass ventilation Pipe, 9-bypass ventilation valve, 10-outlet duct, 11-blower, 12-regeneration air inlet duct, 13-regeneration air damper, 14-ventilator, 15-heater, 16-regeneration air outlet duct , 17-steam supply pipe, 18-condensate drain pipe.

Detailed ways

The present invention will be further described below in conjunction with accompanying drawing 1 and embodiment, but does not limit the present invention.

The blast furnace blast runner dehumidification method of the present invention uses the runner to dehumidify low-temperature and low-humidity air, and mainly includes a blast runner dehumidification link and a runner regeneration link, and also includes a bypass link and a heat source steam link. In the dehumidification process of the rotary dehumidifier, one side of the shell 5 of the rotary dehumidifier is connected to the inlet air pipe 6, and the inlet air valve 7 is installed on the inlet air pipe 6, and the shell 5 of the rotary dehumidifier is equipped with a filter 1, a dehumidification wheel 2 and a rotary Wheel motor 4, the other side of the wheel dehumidifier housing 5 is connected to the outlet air duct 10, and the outlet air duct 10 is connected to the blower 11; Connected, the regenerated air inlet air pipe 12 is equipped with a heater 15, a fan 14 and a regenerated air damper 13 in sequence, and a filter 1 and a regenerated runner 3 are installed in the casing 5 of the rotary dehumidifier, and the casing 5 of the rotary dehumidifier The other side is connected with the regeneration air outlet air pipe 16; in the bypass link, the outlet air pipe 10 is connected with a bypass air pipe 8, and the bypass air pipe 8 is equipped with a bypass air valve 9; in the heat source steam link, the steam supply pipe 17 is The heater 15 provides heat source steam, and the condensation drain pipe 18 discharges the steam condensed water in the heater 15 .

The present invention adopts a lithium chloride or lithium bromide rotary dehumidifier, and the inner runner of the rotary dehumidifier is divided into two fan-shaped areas by a sealing strip—a treatment area with a central angle of 270° and a regeneration area with a central angle of 90°. The runner is made of composite material as base material, compounded with lithium chloride or lithium bromide, active silica gel, molecular sieve and other hygroscopic materials.

The air ducts of the regeneration system (regeneration air inlet air duct 12 and regeneration air outlet air duct 16) should be made of heat-resistant, moisture-resistant, non-combustible or flame-retardant materials, and should be heat-insulated; the regeneration air outlet air duct 16 should not be over Long (3-5m, preferably not more than 5m), there should be a slope of not less than 2‰, facing the direction of the exit (the top of the slope is located near the exit, and the bottom of the slope is located at the far end of the exit), to prevent the condensation of regeneration air and the inflow of condensed water Rotary dehumidifier.

The outdoor air inlet of the dehumidifier inlet air duct 6 should be avoided as far as possible from being arranged in the same direction as the outlet of the regeneration air outlet air duct 16 .

The air valves used in the present invention are butterfly valves of corresponding specifications.

This method dehumidifies through the following specific steps: outdoor air enters the rotary dehumidifier through the inlet air duct 6, firstly passes through the filter 1 and then enters the dehumidification rotor 2 for dehumidification, and the dehumidified dry air enters the outlet air duct 10, passes through The outlet air duct 10 enters the blower 11, and then the blower blows the dry air into the ironmaking blast furnace. When the rotary dehumidifier is working, the side ventilation valve 9 must be closed; the regeneration air is sucked by the fan 14 into the regeneration air inlet duct 12 , and then enter the heater 15 from the air duct 12 for heating, the heated high-temperature air enters the dehumidifier, and after passing through the filter 1, the part of the runner that has just transferred to the previous area of the regenerative runner 3 is heated to make this part of the runner Regeneration is for recycling, and the high-humidity hot air after passing through the regeneration runner is discharged to the atmosphere through the regeneration air outlet duct 16.

The runner of the runner dehumidifier is driven by the runner motor 4 to keep the runner at a certain speed. The rotor in the dehumidification rotor area absorbs water and then transfers to the regeneration area, where the rotor is regenerated by heating with high-temperature air; the regenerated rotor then transfers to the area where the dehumidification rotor was located, and continues to dehumidify the humid air, thus ensuring The continuity of the dehumidification work of the rotary dehumidifier.

The heater 15 uses steam as a heating heat source, and the steam comes from medium-pressure gas or low-pressure gas that has been reduced in temperature and pressure.

When the outdoor air does not need dehumidification season, or when the rotary dehumidifier needs maintenance, close the rotary dehumidifier, close the steam supply pipe 17 valve, close the ventilator 14, close the inlet air valve 7 and the regeneration air damper 13. Open the bypass ventilation valve 9 so that the outdoor air directly enters the blower 11 through the bypass ventilation pipe 8, and then the blower 11 blows the air into the ironmaking blast furnace.

When the rotary dehumidifier is working, the blast volume is controlled by adjusting the inlet air valve 7, and the regenerative air flow is controlled by adjusting the regeneration air valve 13; when the rotary dehumidifier stops working, the drum is controlled by adjusting the bypass air valve 9. Air volume.

This method is suitable for dehumidification of air under low temperature and low humidity conditions of -30 to +40°C, and there will be no condensation in the whole process. However, when the blast air is close to 40°C or higher than 40°C, the dehumidification effect of this device is not obvious. Therefore, this device is best suitable for areas where the summer design temperature is lower than 35°C.

What is disclosed above is only a preferred embodiment of the present invention, and of course it cannot be used to limit the scope of rights of the present invention. Therefore, equivalent changes made according to the patent scope of the present invention, such as changes made to process parameters or devices and improvements still belong to the protection scope of the present invention.

Claims (8)

1. Blast furnace blast runner dehumidification method, using the runner to dehumidify the low-temperature and low-humidity air, characterized in that: the runner is divided into a runner dehumidification area and a runner regeneration area, and can be dehumidified and then regenerated; the two dehumidification areas of the runner The inlet air duct and the outlet air duct are respectively arranged on the side of the runner, and the regeneration air inlet air duct and the regeneration air outlet air duct are respectively arranged on both sides of the regeneration area of the runner; The air valve, the heater steam supply pipe and the heater condensate drain pipe are respectively connected with the heater; the outdoor air enters the dehumidification area of the runner through the inlet air pipe, and the dehumidified dry air is blown into the ironmaking blast furnace; the regeneration air is sucked into the regeneration air inlet After the air duct, it is heated by the heater, and the heated high-temperature air enters the runner regeneration area, and the runners that have just transferred to the runner regeneration area are regenerated for recycling, and the high-temperature air after passing through the runner regeneration area The hot and humid air is discharged to the atmosphere through the regeneration air outlet duct. 2. The rotary dehumidification method according to claim 1, characterized in that: the inlet air duct and the regenerated air outlet air duct are not in the same direction; the inlet air duct is equipped with an inlet air valve; the outlet air duct is connected to the blower; The air pipe is connected to the bypass ventilation pipe, and the bypass ventilation pipe is equipped with a bypass ventilation valve; when the rotary dehumidifier is working, ensure that the bypass ventilation valve is closed. 3. The rotary dehumidification method according to claim 1 or 2, characterized in that: the rotary dehumidifier comprises a casing, a filter placed in the casing, a rotary wheel and a rotary motor, and the filter is placed in front of the rotary wheel ; The dehumidification area of the runner and the regeneration area of the runner are fan-shaped areas separated by sealing strips: the runner is set to rotate continuously under the drive of the motor and staggered in the direction of the two areas. 4. The dehumidification method according to claim 3, characterized in that: the central angle of the dehumidification zone of the rotary wheel is 270°, and the central angle of the regeneration zone of the rotary wheel is 90°. 5. The method according to claim 1, 2 or 4, characterized in that: the rotary dehumidifier adopts a lithium chloride or lithium bromide rotary dehumidifier; the rotary wheel is a lithium chloride or lithium bromide rotary The material is processed as a base material and a hygroscopic material. The main components of the hygroscopic material include active lithium chloride or lithium bromide, as well as permanent silica gel and molecular sieve. 6. The dehumidification method according to claim 5, characterized in that: the regenerated air inlet air duct and the regenerated air outlet air duct are made of heat-resistant, moisture-resistant, non-combustible or flame-retardant materials after heat insulation treatment; The length of the regenerated air outlet duct is 3-5m, the slope is not less than 2‰, and the slope is in the direction of the outlet. 7. The dehumidification method according to claim 1 or 2 or 4 or 6, characterized in that: the heater uses steam as a heating heat source, and the steam is medium-pressure or low-pressure gas that has undergone reduced temperature and pressure reduction. 8. The dehumidification method according to claim 7, characterized in that: the air valves are all butterfly valves.