Device for eliminating metal bonding of waste heat boiler

Abstract

A device for eliminating metal bonding of a waste heat boiler comprises an evaporative cooling flue, an evaporative cooler, a gravity dust collector, a cyclone dust collector and the waste heat boiler, the front end of the evaporative cooling flue is connected with a smelting reduction furnace, and the rear end of the evaporative cooling flue is connected with the evaporative cooler; the evaporative cooler is connected with an inlet of the gravity dust collector through a connecting flue I; an outlet of the gravity dust collector is connected with an inlet of the cyclone dust collector through a connecting flue II; and an outlet of the cyclone dust collector is connected with an inlet of the waste heat boiler through a connecting flue III. By arranging the gasification cooling flue and the evaporative cooler, low-melting-point alkali metal carbonate is removed in advance, slag bonding of the waste heat boiler is eliminated, and meanwhile it is ensured that the waste heat boiler continues to recycle sensible heat.

Description

Technical Field

[0001] Embodiments of the present disclosure generally relate to the field of iron and steel smelting, and more particularly, to a device for eliminating metal adhesion in a waste heat boiler. Background Art

[0002] When a smelting reduction furnace produces high-purity pig iron, a large amount of high-temperature raw coal gas (1450 - 1600 °C) containing impurities and sensible heat is generated. The sensible heat therein can be recovered through a vaporization cooling flue and a waste heat boiler for power generation; the impurities are mainly semi-coke and iron-containing oxides, and there are also a small amount of inorganic substances such as SiO2, Al2O3, CaO, MgO, K2O, Na2O, etc., which can be recovered and utilized through gravity dust removal, cyclone dust removal, and dry dust removal. Finally, the low-temperature clean coal gas can also be recovered and utilized by downstream gas users.

[0003] During production, it is often found that the evaporator and economizer pipes in the waste heat boiler are prone to alkali metal adhesion. In the light case, it leads to a reduction in sensible heat recovery, and in the severe case, it causes pipe rupture, water leakage, and production interruption. After analyzing the slag deposits, the main reason is that the temperature of the raw coal gas entering the waste heat boiler is 780 - 800 °C, and the low-melting-point alkali metal carbonates crystallize on the evaporator pipes at this temperature, resulting in slag formation. This phenomenon has seriously threatened the normal production of enterprises and caused direct or indirect economic losses to enterprises. Therefore, we propose a device for eliminating adhesion in the waste heat boiler. Summary of the Utility Model

[0004] The purpose of the present utility model is to provide a device for eliminating metal adhesion in a waste heat boiler to solve the problem of current adhesion in the waste heat boiler.

[0005] To solve the above technical problems, the technical solution adopted by the present utility model is as follows:

[0006] A device for eliminating metal adhesion in a waste heat boiler includes a vaporization cooling flue (2), an evaporation cooler (3), a gravity dust collector (5), a cyclone dust collector (7), and a waste heat boiler (9). The front end of the vaporization cooling flue (2) is connected to a smelting reduction furnace (1), and the rear end is connected to the evaporation cooler (3); the evaporation cooler (3) is connected to the inlet of the gravity dust collector (5) through a connecting flue I (4); the outlet of the gravity dust collector (5) is connected to the inlet of the cyclone dust collector (7) through a connecting flue II (6); the outlet of the cyclone dust collector (7) is connected to the inlet of the waste heat boiler (9) through a connecting flue III (8).

[0007] Furthermore, a spraying system (31) is arranged above the evaporation cooler (3), and desalted water atomized by steam or nitrogen, or pulverized bituminous coal is used to spray and cool the high-temperature raw coal gas.

[0008] Furthermore, the injection system (31) includes an injection header pipe (10) and injection guns (11). The injection header pipe (10) is fixed on the outer periphery of the evaporation cooler (3), and injection guns are installed thereon. The injection guns pass through the evaporation cooler and enter the interior to inject atomized water or pulverized bituminous coal into the high-temperature raw coal gas.

[0009] Furthermore, 6 to 12 injection guns (11) are installed on the injection header pipe (10).

[0010] Furthermore, the injection guns (11) are evenly distributed on the injection header pipe (10).

[0011] Furthermore, the injection guns have a telescopic function, which is convenient for adjusting the injection position and replacement.

[0012] Furthermore, a flow regulating valve is installed on the injection gun, and the injection water flow or coal injection volume can be controlled manually or remotely.

[0013] Furthermore, the length of the injection gun is 1000 to 1500 mm.

[0014] Furthermore, a pneumatic quick cut-off valve and a butterfly valve are arranged on the periphery of the injection header pipe, and the injection medium can be switched according to the actual situation. The pneumatic quick cut-off valve and the butterfly valve can be individually cut off or opened on-site, or each medium injection can be individually cut off or controlled remotely.

[0015] Furthermore, each injection gun can be individually cut off or opened by a manual cut-off valve, or individually cut off or opened by remote control, or all injection guns can be controlled as a whole.

[0016] Advantages and effects of the present utility model: By arranging the gasification cooling flue and the evaporation cooler, the high-temperature raw coal gas at 1450 - 1600 °C passes through the gasification cooling flue and the evaporation cooler and the temperature drops to 600 - 750 °C after entering the waste heat boiler. This not only removes the low-melting-point alkali metal carbonate in advance and eliminates the slagging of the waste heat boiler, but also ensures that the waste heat boiler continues to recover sensible heat. Description of the Drawings

[0017] Figure 1 is a schematic diagram of the device for eliminating the slagging of the waste heat boiler of the present utility model.

[0018] Figure 2 is a schematic diagram of the injection system at the upper part of the evaporation cooler.

[0019] Wherein: 1. Smelting reduction furnace; 2. Gasification cooling flue; 3. Evaporation cooler; 31. Injection system; 4. Connecting flue I; 5. Gravity dust collector; 6. Connecting flue II; 7. Cyclone dust collector; 8. Connecting flue III; 9. Waste heat boiler; 10. Injection header pipe; 11. Injection gun Detailed Embodiments

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present utility model clearer, the technical solutions of the embodiments of the present utility model will be described clearly and completely below. Apparently, the described embodiments are some, but not all, of the embodiments of the present utility model. All other embodiments obtained by those of ordinary skill in the art based on the described embodiments of the present utility model without creative efforts shall fall within the protection scope of the present utility model.

[0021] The technical solutions of the present utility model will be further explained and illustrated below in conjunction with specific embodiments.

[0022] A device for eliminating metal adhesion in a waste heat boiler includes a vaporization cooling flue 2, an evaporation cooler 3, a gravity dust collector 5, a cyclone dust collector 7, and a waste heat boiler 9. The front end of the vaporization cooling flue is connected to a smelting reduction furnace, and the rear end is connected to the evaporation cooler; the evaporation cooler is connected to the inlet of the gravity dust collector 5 through a connecting flue I; the outlet of the gravity dust collector is connected to the inlet of the cyclone dust collector 7 through a connecting flue II; the outlet of the cyclone dust collector is connected to the inlet of the waste heat boiler through a connecting flue III. The temperature of the high-temperature raw gas generated by the smelting reduction furnace is 1450 - 1600 °C, and the temperature drops to 800 - 1000 °C after passing through the vaporization cooling flue. A spraying system 31 is arranged above the evaporation cooler for physically and chemically cooling the high-temperature raw gas, so that the temperature of the high-temperature raw gas entering the waste heat boiler is controlled at 600 - 750 °C.

[0023] When the spraying medium of the spraying system 31 is liquid water, demineralized water is selected and atomized by steam or nitrogen, and the steam comes from the vaporization cooling flue or the steam drum of the waste heat boiler.

[0024] When the spraying medium of the spraying system 31 is powder, bituminous coal is selected and transported by nitrogen or compressed air.

[0025] The spraying system includes a spraying header pipe 10 and a spray gun 11.

[0026] The spray gun has a telescopic function, which is convenient for adjusting the spraying position and replacement.

[0027] A flow regulating valve is installed on the spray gun, and the spraying water flow or coal spraying amount can be manually or remotely controlled.

[0028] Preferably, the length of the spray gun is 1000 - 1500 mm.

[0029] Furthermore, the spraying header pipe is fixed on the outer periphery of the evaporation cooler, and 6 - 12 spray guns are evenly arranged thereon. The spray guns pass through the evaporation cooler and enter the interior to spray atomized water or bituminous coal powder on the high-temperature raw gas.

[0030] Further, a pneumatic quick cut-off valve and a butterfly valve are arranged outside the blowing annular pipe, and the blowing medium can be switched according to the actual situation. The above valves can be cut off or opened individually on-site, or each medium blowing can be cut off or controlled remotely.

[0031] Further, each spray gun can be cut off or opened individually by a manual stop valve, or each spray gun can be cut off or controlled individually through remote control, or all spray guns can be controlled as a whole.

[0032] Preferably, the pressure of the blown desalted water is 0.5 - 0.6 MPa, the pressure of steam or nitrogen is 0.8 - 1.0 MPa, and the injection water flow rate does not exceed 20 m 3 / h;

[0033] Preferably, when blowing bituminous coal, the conveying gas flow rate is 500 - 1000 Nm3 / h, the carrier gas pressure is 0.4 - 0.6 MPa, and the bituminous coal flow rate is 5 - 10 t / h.

[0034] Further, the raw coal gas obtains the coarse particle semicoke dust removal ash containing low melting point alkali metal carbonate through the gravity dust collector and the cyclone dust collector, and the raw coal gas entering the waste heat boiler no longer contains low melting point alkali metal carbonate.

[0035] Example 1

[0036] A device for eliminating metal bonding in a waste heat boiler includes a vaporization cooling flue 2, an evaporation cooler 3, a gravity dust collector 5, a cyclone dust collector 7, and a waste heat boiler 9. The front end of the vaporization cooling flue is connected to the smelting reduction furnace 1, and the rear end is connected to the evaporation cooler; the evaporation cooler is connected to the inlet of the gravity dust collector 5 through the connecting flue I; the outlet of the gravity dust collector is connected to the inlet of the cyclone dust collector 7 through the connecting flue II; the outlet of the cyclone dust collector is connected to the inlet of the waste heat boiler through the connecting flue III.

[0037] The high-temperature raw coal gas generated by the smelting reduction furnace has a temperature of 1512 °C. After passing through the vaporization cooling flue, the temperature drops to 895 °C, and after passing through the evaporation cooler, the gravity dust collector, and the cyclone dust collector, the temperature of the raw coal gas entering the waste heat boiler drops to 722 °C.

[0038] 12 spray guns are arranged on the blowing system installed on the evaporation cooler, and the blowing medium is desalted water. The desalted water is atomized by the steam on the steam drum of the vaporization cooling flue. During production, atomized cooling water is blown into the passing raw coal gas. The blowing water pressure is 0.52 MPa, the steam pressure is 0.83 MPa, and the water spraying flow rate is 10.38 m 3 / h.

[0039] No slagging phenomenon occurs in the waste heat boiler, indicating that the low melting point alkali metal carbonate has been removed by the gravity dust collector and the cyclone dust collector.

[0040] Example 2

[0041] A device for eliminating metal adhesion in a waste heat boiler, comprising a vaporization cooling flue 2, an evaporation cooler 3, a gravity dust collector 5, a cyclone dust collector 7 and a waste heat boiler 9. The front end of the vaporization cooling flue is connected to the smelting reduction furnace 1, and the rear end is connected to the evaporation cooler; the evaporation cooler is connected to the inlet of the gravity dust collector 5 through the connecting flue I; the outlet of the gravity dust collector is connected to the inlet of the cyclone dust collector 7 through the connecting flue II; the outlet of the cyclone dust collector is connected to the inlet of the waste heat boiler through the connecting flue III.

[0042] The temperature of the high-temperature raw coal gas generated by the smelting reduction furnace is 1542 °C. After passing through the vaporization cooling flue, the temperature drops to 876 °C, and after passing through the evaporation cooler, the gravity dust collector and the cyclone dust collector, the temperature of the raw coal gas entering the waste heat boiler drops to 717 °C.

[0043] There are 12 spray guns arranged on the spraying system installed on the evaporation cooler. The spraying medium is pulverized bituminous coal, and nitrogen is used to transport the bituminous coal. During production, pulverized bituminous coal is sprayed into the passing raw coal gas. The flow rate of the conveying gas is 780 Nm 3 / h, the pressure is 0.5 MPa, and the bituminous coal spraying amount is 9.2 t / h.

[0044] No slagging phenomenon occurs in the waste heat boiler, indicating that the low-melting-point alkali metal carbonate has been removed by the gravity dust collector and the cyclone dust collector.

[0045] Although the disclosed embodiments of the present invention are as above, the above content is only an embodiment adopted for the convenience of understanding the present invention and is not intended to limit the present invention. Any person skilled in the art within the scope of the present invention can make any modifications and changes in the form and details of the implementation without departing from the spirit and scope disclosed by the present invention. However, the scope of patent protection of the present invention shall still be subject to the scope defined by the appended claims.

Claims

1. A device for eliminating metal adhesion in a waste heat boiler, characterized in that: The invention comprises a vaporization cooling flue (2), an evaporative cooler (3), a gravity dust collector (5), a cyclone dust collector (7) and a waste heat boiler (9), wherein the front end of the vaporization cooling flue (2) is connected to the smelting reduction furnace (1), and the rear end is connected to the evaporative cooler (3); the evaporative cooler (3) is connected to the inlet of the gravity dust collector (5) through a connecting flue I (4); the outlet of the gravity dust collector (5) is connected to the inlet of the cyclone dust collector (7) through a connecting flue II (6); and the outlet of the cyclone dust collector (7) is connected to the inlet of the waste heat boiler (9) through a connecting flue III (8).

2. The device for eliminating metal adhesion of a waste heat boiler according to claim 1, characterized in that: A spraying system (31) is arranged on the upper part of the evaporative cooler (3), and uses desalted water atomized by steam or nitrogen, or bituminous coal powder, to spray and cool the high-temperature raw coal gas.

3. The device for eliminating metal adhesion of a waste heat boiler according to claim 2, characterized in that: The spraying system (31) comprises a spraying ring tube (10) and a spray gun (11). The spraying ring tube (10) is fixed on the outer periphery of the evaporative cooler (3) and is provided with a spray gun. The spray gun passes through the evaporative cooler and enters the interior to spray atomized water or bituminous coal powder on the high-temperature raw coal gas.

4. The device for eliminating metal adhesion of a waste heat boiler according to claim 3, characterized in that: 6 to 12 spray guns (11) are installed on the spray ring pipe (10).

5. The device for eliminating metal adhesion of a waste heat boiler according to claim 3 or 4, characterized in that: The spray guns (11) are evenly distributed on the spray ring pipe (10).

6. The device for eliminating metal adhesion of a waste heat boiler according to claim 5, characterized in that: The spray gun has a telescopic function, which is convenient for adjusting the spraying position and replacing.

7. The device for eliminating metal adhesion of a waste heat boiler according to claim 6, characterized in that: The spray gun is provided with a flow regulating valve, which can manually or remotely control the spraying water flow or the spraying coal amount.

8. The device for eliminating metal adhesion of a waste heat boiler according to claim 7, characterized in that: The length of the spray gun is 1000-1500 mm.

9. The device for eliminating metal adhesion of a waste heat boiler according to claim 8, characterized in that: Pneumatic quick-cut valves and butterfly valves are arranged on the periphery of the injection ring pipe, and the injection medium can be switched according to actual conditions. The pneumatic quick-cut valves and butterfly valves can be individually cut off or opened on site, or each medium injection can be individually or cut off through remote control.

10. The device for eliminating metal adhesion of a waste heat boiler according to claim 9, characterized in that: Each spray gun can be shut off or opened individually by manual shut-off valve, or individually shut off or opened by remote control, or all spray guns can be controlled as a whole.

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