A method for recycling smelting flue gas drying materials

Abstract

The invention discloses a method for recycling and utilizing smelting flue gas drying materials, which belongs to the field of tail gas treatment and pyrometallurgical technology. The steps are: lead concentrate, zinc leaching slag, roasted ore, flux and crushed coal are mixed and put into a molten pool, and stirred for reduction; CO is sent to the tail gas treatment system after passing through a flue gas cooler, a dust collector and cooling with the flue gas; CO-containing flue gas with a small amount of smoke dust is purified and enriched again, and then sent to the drying system; ignited by a burner ignition device to complete the treatment. The invention can effectively purify CO tail gas, and realize CO enrichment combustion and utilization of dry materials. The method of the invention has a wide range of CO tail gas that can be recycled and utilized, and can be recycled above 10000ppm. The method of the invention is simple to operate and has a high degree of automation. DCS control can be realized, and the alarm, interlocking and purge devices can be set safely and reliably. The scheme of the invention can effectively reduce the production cost of the enterprise.

Description

Technical Field

[0001] The invention relates to the technical field of tail gas treatment and pyrometallurgy, and in particular to a method for recycling smelting flue gas drying materials. Background Art

[0002] At present, the excess CO generated in the metallurgical process mainly adopts the secondary combustion in the furnace and direct exhaust. If the secondary combustion in the furnace is adopted, the main problems include: the atmosphere in the furnace is difficult to control, the energy of the combustion after the secondary combustion changes dramatically in the furnace area, which will cause a large temperature difference change to the refractory materials, water jacket and furnace top of the metallurgical furnace, and the change of deformation stress will affect the safe and stable operation of the metallurgical furnace, refractory materials and boiler. On the one hand, the flow rate of the discharge process is difficult to control, which poses a safety risk. On the other hand, the exhaust will pollute the atmosphere.

[0003] Therefore, providing a method for recycling smelting flue gas drying materials is a technical problem that technical personnel in this field urgently need to solve. Summary of the invention

[0004] In view of this, the present invention provides a method for recycling smelting flue gas drying materials, using the CO-containing tail gas generated in the smelting process of the metallurgical furnace as the raw material drying fuel, achieving process innovation and breakthrough, and having obvious energy-saving effect, stable production control, and outstanding production benefits. The method of the present invention is simple to operate and has a high degree of automation.

[0005] To achieve the above object, the present invention adopts the following technical solution:

[0006] A method for recycling smelting flue gas dried materials, comprising the following steps:

[0007] (1) Lead concentrate, zinc leaching slag, zinc roasted sand, flux and crushed coal are mixed and put into a molten pool, where a violent reduction reaction occurs and a strong reducing atmosphere is formed in the furnace;

[0008] (2) In the strong reducing atmosphere formed, the excess CO is cooled in the flue gas cooler along with the flue gas, then removed by the dust collector and cooled to below 120°C before being sent to the exhaust gas treatment system;

[0009] (3) The exhaust gas treatment system purifies and enriches the CO-containing flue gas with a small amount of smoke and dust, and then transports the flue gas to the drying system;

[0010] (4) A CO detection device is set before the ignition device to detect CO in real time. If the CO concentration is greater than 10,000 ppm, the drying system will automatically ignite through the burner ignition device according to production needs to complete the recycling of smelting flue gas drying materials.

[0011] Furthermore, the mass ratio of the lead concentrate, zinc leaching slag, zinc roasted sand, flux and crushed coal is 10:110-12:2-5:0.3-0.8:0..3-0.8.

[0012] Furthermore, the crushed coal is lump coal.

[0013] Furthermore, the lump coal has C ≥ 60%, S ≤ 3%, volatile matter ≤ 10%, ash ≤ 24%, and moisture ≤ 8%; the lump coal particle size is 15-30 mm;

[0014] Furthermore, the flux is limestone and / or quartz sand.

[0015] Furthermore, the reduction reaction temperature in step (1) is 900°C to 1150°C.

[0016] Furthermore, the exhaust gas treatment system in step (2) includes an explosion-proof dust collector and an induced draft fan connected in series.

[0017] Furthermore, after the burner ignition device in step (4) automatically ignites, the fan frequency is set and adjusted according to the temperature to control the CO delivery amount and temperature.

[0018] The beneficial effects of the present invention are:

[0019] The present invention can effectively purify CO tail gas and realize CO enrichment combustion and utilization of dry materials. The method of the present invention has a wide range of CO tail gas recovery and utilization, and can achieve recovery above 10000ppm. The method of the present invention is simple to operate and has a high degree of automation. DCS control can be realized, and the alarm, interlocking, and purge devices can be set safely and reliably. The scheme of the present invention can effectively reduce the production cost of enterprises. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 The present invention is a process flow chart of the method for recycling smelting flue gas drying materials. DETAILED DESCRIPTION

[0021] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] In the present invention, the lump coal has C≥60%, S≤3%, volatile matter≤10%, ash≤24%, and moisture≤8%; the particle size of the lump coal is distributed in the range of 15-30 mm;

[0023] Example 1

[0024] A method for recycling smelting flue gas drying materials

[0025] (1) Lead concentrate, zinc leaching slag, zinc roasted sand, limestone and lump coal are mixed in a mass ratio of 10:11:3:0.5:0.5 and added into a molten pool, a violent reduction reaction occurs in the molten pool at 1000° C., and a strong reducing atmosphere is formed in the furnace;

[0026] (2) In the strong reducing atmosphere formed, the excess CO is cooled in the flue gas cooler and then removed by the dust collector to a temperature of 120°C. The particulate matter in the flue gas is ≤50mg / m 3 The tail gas treatment system is composed of explosion-proof dust collector and induced draft fan connected in series.

[0027] (3) The exhaust gas treatment system purifies and enriches the CO-containing flue gas with a small amount of smoke and dust, and then transports the flue gas to the drying system;

[0028] (4) A CO detection device is set before the ignition device to detect CO in real time. If the CO concentration is greater than 10000ppm, the drying system will automatically ignite through the burner ignition device according to production needs to complete the recycling of smelting flue gas drying materials. After the burner ignition device automatically ignites, the fan frequency is adjusted according to the temperature setting to control the CO delivery volume and temperature.

[0029] Example 2 A method for recycling smelting flue gas drying materials

[0030] (1) Lead concentrate, zinc leaching slag, zinc roasted sand, limestone and lump coal are mixed in a mass ratio of 10:10:5:0.3:0.3 and added into a molten pool, a violent reduction reaction occurs in the molten pool at 1000° C., and a strong reducing atmosphere is formed in the furnace;

[0031] (2) In the strong reducing atmosphere formed, the excess CO is cooled in the flue gas cooler and then removed by the dust collector to a temperature of 120°C. The particulate matter in the flue gas is ≤50mg / m 3 The tail gas treatment system is composed of explosion-proof dust collector and induced draft fan connected in series.

[0032] (3) The exhaust gas treatment system purifies and enriches the CO-containing flue gas with a small amount of smoke and dust, and then transports the flue gas to the drying system;

[0033] (4) A CO detection device is set before the ignition device to detect CO in real time. If the CO concentration is greater than 10000ppm, the drying system will automatically ignite through the burner ignition device according to production needs to complete the recycling of smelting flue gas drying materials. After the burner ignition device automatically ignites, the fan frequency is adjusted according to the temperature setting to control the CO delivery volume and temperature.

[0034] Example 3

[0035] A method for recycling smelting flue gas drying materials

[0036] (1) Lead concentrate, zinc leaching slag, zinc roasted sand, limestone and lump coal are mixed in a mass ratio of 10:12:2:0.8:0.8 and added into a molten pool, a violent reduction reaction occurs in the molten pool at 1000° C., and a strong reducing atmosphere is formed in the furnace;

[0037] (2) In the strong reducing atmosphere formed, the excess CO is cooled in the flue gas cooler and then removed by the dust collector to a temperature of 120°C. The particulate matter in the flue gas is ≤50mg / m 3 The tail gas treatment system is composed of explosion-proof dust collector and induced draft fan connected in series.

[0038] (3) The exhaust gas treatment system purifies and enriches the CO-containing flue gas with a small amount of smoke and dust, and then transports the flue gas to the drying system;

[0039] (4) A CO detection device is set before the ignition device to detect CO in real time. If the CO concentration is greater than 10000ppm, the drying system will automatically ignite through the burner ignition device according to production needs to complete the recycling of smelting flue gas drying materials. After the burner ignition device automatically ignites, the fan frequency is adjusted according to the temperature setting to control the CO delivery volume and temperature.

[0040] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A method for recycling smelting flue gas drying materials, characterized in that: The following steps are involved: (1) Lead concentrate, zinc leaching slag, zinc roasted sand, flux and crushed coal are mixed and put into a molten pool, where a violent reduction reaction occurs and a strong reducing atmosphere is formed in the furnace; (2) In the strong reducing atmosphere formed, the excess CO is cooled in the flue gas cooler along with the flue gas, then removed by the dust collector and cooled to below 120°C before being sent to the exhaust gas treatment system; (3) The exhaust gas treatment system purifies and enriches the CO-containing flue gas with a small amount of smoke and dust, and then transports the flue gas to the drying system; (4) A CO detection device is set before the ignition device to detect CO in real time. If the CO concentration is greater than 10000ppm, the drying system will automatically ignite through the burner ignition device according to production needs to complete the recycling of smelting flue gas drying materials.

2. A method for recycling smelting flue gas drying materials according to claim 1, characterized in that: The mass ratio of the lead concentrate, zinc leaching slag, zinc roasted sand, flux and crushed coal is 10:110-12:2-5:0.3-0.8:0..3-0.

8.

3. A method for recycling smelting flue gas drying materials according to claim 1 or 2, characterized in that: The crushed coal is lump coal.

4. A method for recycling smelting flue gas drying materials according to claim 3, characterized in that: The lump coal has C≥60%, S≤3%, volatile matter≤10%, ash≤24%, and moisture≤8%; and the particle size of the lump coal is 15-30 mm.

5. A method for recycling smelting flue gas drying materials according to claim 1 or 2, characterized in that: The flux is limestone and / or quartz sand.

6. A method for recycling smelting flue gas drying materials according to claim 1, characterized in that: The reduction reaction temperature in step (1) is 900°C to 1150°C.

7. A method for recycling smelting flue gas drying materials according to claim 1, characterized in that: The tail gas treatment system in step (2) comprises an explosion-proof dust collector and an induced draft fan connected in series.

8. A method for recycling smelting flue gas drying materials according to claim 1, characterized in that: After the burner ignition device in step (4) automatically ignites, the fan frequency is set and adjusted according to the temperature to control the CO delivery amount and temperature.

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