Waste heat recycling device for calcium oxide production

Abstract

The utility model relates to the technical field of calcium oxide production, in particular to a calcium oxide production waste heat recycling device. The calcium oxide production waste heat recycling device comprises a washing kettle, the washing kettle is connected with a crushing and grinding box through a drying box, the crushing and grinding box is connected with a vertical cooler through a rotary kiln, the rotary kiln is connected with an induced draft fan through a dust fall heat exchange box, and the induced draft fan is connected with the washing kettle through a waste heat recycling water tank. According to the device, the dust falling heat exchange box and the waste heat recovery water tank are used in cooperation, dust falling heat exchange treatment is conducted on smoke exhausted by the rotary kiln, the exchanged heat is used for crushing, grinding and washing of raw materials, the waste heat utilization efficiency is greatly improved, and the production cost is saved; heat in the vertical cooler is used for the drying box after being exchanged, so that the production efficiency is greatly improved.

Description

Technical Field

[0001] The utility model relates to the technical field of calcium oxide production, in particular to a device for recovering and utilizing waste heat from calcium oxide production. Background Art

[0002] The preparation of calcium oxide is done by calcining limestone (calcium carbonate, CaCO3), which is a decomposition reaction. At high temperatures, limestone decomposes into calcium oxide (CaO) and carbon dioxide (CO2). The chemical equation for this reaction is as follows:

[0003] CaCO3→CaO+CO2.

[0004] The reaction is exothermic, meaning that heat is released during the reaction. When limestone is burned, the calcium carbonate decomposes at high temperatures, releasing energy.

[0005] In workshop production, the large amount of heat generated during the preparation of calcium oxide has not been better utilized. Especially in the early stage of limestone pretreatment, if the temperature of the limestone after pretreatment is low, it will also have a great impact on the later production efficiency. Utility Model Content

[0006] In view of the above deficiencies in the prior art, the purpose of the utility model is to provide a waste heat recovery and utilization device for calcium oxide production. Through the coordinated use of a dust reduction heat exchange box and a waste heat recovery water tank, the flue gas discharged from the rotary kiln is subjected to dust reduction and heat exchange treatment, and the exchanged heat is used for crushing, grinding and washing of raw materials, which greatly improves the waste heat utilization efficiency and saves production costs; by exchanging heat in the vertical cooler and using it in a drying box, the production efficiency is greatly improved.

[0007] The utility model is realized by adopting the following technical solutions:

[0008] The calcium oxide production waste heat recovery and utilization device comprises a water washing kettle, which is connected to a crushing and grinding box through a drying box, the crushing and grinding box is connected to a vertical cooler through a rotary kiln, the rotary kiln is connected to an induced draft fan through a dust reduction heat exchange box, and the induced draft fan is connected to the water washing kettle through a waste heat recovery water tank.

[0009] The inner diameter of the dust reduction heat exchanger box is much larger than the diameter of the pipe entering the dust reduction heat exchanger box. After the impurities enter the dust reduction heat exchanger box with the gas, the flow rate is significantly reduced, and then the impurities settle and accumulate under the action of gravity, thereby achieving the purpose of dust reduction. The bottom of the dust reduction heat exchanger box is inclined, which is conducive to the collection of impurities.

[0010] The water washing kettle is provided with a water washing kettle feed port, a primary material guide plate is connected between the water washing kettle and the drying box, and a magnet is provided under the primary material guide plate.

[0011] The vertical cooler is provided with an inner cooler shell inside, and an outer cooler shell is provided outside the inner cooler shell. The rotary kiln is connected with the inner cooler shell through a secondary material guide plate.

[0012] The dust reduction heat exchange box is provided with a dust reduction heat exchange box coil inside, the dust reduction heat exchange box coil is connected with a dust reduction heat exchange box coil inlet pipe, and the dust reduction heat exchange box coil is connected to the crushing and grinding box through the dust reduction heat exchange box coil outlet pipe. The dust reduction heat exchange box coil is in gas phase, and gas-to-gas heat exchange is performed in the dust reduction heat exchange box.

[0013] The waste heat recovery water tank is provided with a waste heat recovery water tank coil inside, the induced draft fan is connected to the waste heat recovery water tank coil inside, and the waste heat recovery water tank is connected to the washing kettle through a liquid phase waste heat recovery water tank pipeline. A water inlet is provided on the waste heat recovery water tank, and gas-liquid heat exchange is performed in the waste heat recovery water tank, so that the waste heat recovery water tank achieves the purpose of fully utilizing the waste heat.

[0014] The vertical cooler is connected to the drying box through a drying box inlet pipe, and a dust reduction heat exchange box inlet pipe is connected between the rotary kiln and the dust reduction heat exchange box.

[0015] The working principle of the utility model is:

[0016] The limestone enters the water washing kettle for cleaning to remove impurities on the surface, and then enters the drying box after iron removal by the primary guide plate and magnet, and then enters the rotary kiln for reaction through the crushing and grinding box; the exhaust gas in the rotary kiln enters the dust reduction heat exchange box for a heat exchange, and the gas heated in the dust reduction heat exchange box coil enters the crushing and grinding box, and then the exhaust gas enters the waste heat recovery water tank coil through the induced draft fan to heat the water in the waste heat recovery water tank, and the heated water enters the water washing kettle; the product generated after the reaction is completed enters the vertical cooler through the secondary guide plate, and the gas that cools the product enters the drying box through the drying box inlet pipe. Among them, the inner diameter of the dust reduction heat exchange box is much larger than the diameter of the dust reduction heat exchange box inlet pipe. After the impurities enter the dust reduction heat exchange box with the gas, the flow rate is significantly reduced, and then the impurities settle and accumulate under the action of gravity, thereby achieving the purpose of dust reduction. The bottom of the dust reduction heat exchange box is inclined, which is conducive to the collection of impurities.

[0017] Compared with the prior art, the beneficial effects of the utility model are:

[0018] By adopting the waste heat recovery and utilization device for calcium oxide production of the utility model, dust reduction and heat exchange treatment is carried out on the flue gas discharged from the rotary kiln through the coordinated use of the dust reduction heat exchange box and the waste heat recovery water tank. The exchanged heat is used for crushing, grinding and washing of raw materials, which greatly improves the waste heat utilization efficiency and saves production costs. The heat in the vertical cooler is exchanged and used in the drying box, which greatly improves the production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the structure of the waste heat recovery and utilization device for calcium oxide production of the utility model;

[0020] In the figure: 1. Water washing kettle; 2. Drying box; 3. Crushing and grinding box; 4. Rotary kiln; 5. Vertical cooler; 6. Dust reduction heat exchange box; 7. Waste heat recovery water tank; 8. Feed inlet of water washing kettle; 9. Cooler inner shell; 10. Cooler outer shell; 11. Dust reduction heat exchange box coil; 12. Induced draft fan; 13. Waste heat recovery water tank coil; 14. Primary guide plate; 15. Magnet; 16. Secondary guide plate; 17. Dust reduction heat exchange box inlet pipe; 18. Dust reduction heat exchange box coil inlet pipe; 19. Dust reduction heat exchange box coil outlet pipe; 20. Liquid phase waste heat recovery water tank outlet pipe; 21. Drying box inlet pipe. DETAILED DESCRIPTION

[0021] In order to make the purpose and technical solution of the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings.

[0022] Example 1

[0023] like Figure 1 As shown, the waste heat recovery and utilization device for calcium oxide production includes a water washing kettle 1, which is connected to a crushing and grinding box 3 through a drying box 2, and the crushing and grinding box 3 is connected to a vertical cooler 5 through a rotary kiln 4, and the rotary kiln 4 is connected to an induced draft fan 12 through a dust reduction heat exchange box 6, and the induced draft fan 12 is connected to the water washing kettle 1 through a waste heat recovery water tank 7. The water washing kettle 1 is provided with a water washing kettle feed port 8, and a primary guide plate 14 is connected between the water washing kettle 1 and the drying box 2, and a magnet 15 is provided below the primary guide plate 14. A cooler inner shell 9 is provided inside the vertical cooler 5, and a cooler outer shell 10 is provided outside the cooler inner shell 9, and the rotary kiln 4 is connected to the cooler inner shell 9 through a secondary guide plate 16. The dust reduction heat exchange box 6 is provided with a dust reduction heat exchange box coil 11 inside, and the dust reduction heat exchange box coil 11 is connected with a dust reduction heat exchange box coil inlet pipe 18, and the dust reduction heat exchange box coil 11 is connected to the crushing and grinding box 3 through the dust reduction heat exchange box coil outlet pipe 19. The dust reduction heat exchange box coil 11 is in gas phase, and gas-to-gas heat exchange is performed in the dust reduction heat exchange box 6. The waste heat recovery water tank 7 is provided with a waste heat recovery water tank coil 13 inside, and the induced draft fan 12 is connected to the waste heat recovery water tank coil 13 inside, and the waste heat recovery water tank 7 is connected to the washing kettle 1 through the liquid phase waste heat recovery water tank outlet pipe 20. The waste heat recovery water tank 7 is provided with a water inlet, and the waste heat recovery water tank 7 is in gas-liquid heat exchange, and the waste heat recovery water tank 7 serves the purpose of fully utilizing the waste heat. The vertical cooler 5 is connected to the drying box 2 through a drying box inlet pipe 21 , and a dust reduction heat exchange box inlet pipe 17 is connected between the rotary kiln 4 and the dust reduction heat exchange box 6 .

[0024] The above-mentioned calcium oxide production waste heat recovery and utilization device, when in operation, comprises the following steps:

[0025] (1) The limestone enters the water washing kettle 1 for cleaning to remove impurities on the surface, and then enters the drying box 2 after iron removal by the primary guide plate 14 and the magnet 15, and then enters the rotary kiln 4 for reaction through the crushing and grinding box 3; (2) The exhaust gas in the rotary kiln 4 enters the dust reduction heat exchange box 6 for a heat exchange, and the gas heated in the dust reduction heat exchange box coil 11 enters the crushing and grinding box 3, and then the exhaust gas enters the waste heat recovery water tank coil 13 through the induced draft fan 12 to heat the water in the waste heat recovery water tank 7, and the heated water enters the water washing kettle 1; (3) The product generated after the reaction is completed enters the vertical cooler 5 through the secondary guide plate 16, and the gas used to cool the product enters the drying box 2 through the drying box inlet pipe 21.

Claims

1. A device for recovering waste heat from calcium oxide production, characterized in that: The invention comprises a water washing kettle (1), wherein the water washing kettle (1) is connected to a crushing and grinding box (3) via a drying box (2), the crushing and grinding box (3) is connected to a vertical cooler (5) via a rotary kiln (4), the rotary kiln (4) is connected to an induced draft fan (12) via a dust reduction heat exchange box (6), and the induced draft fan (12) is connected to the water washing kettle (1) via a waste heat recovery water tank (7).

2. The calcium oxide production waste heat recovery and utilization device according to claim 1 is characterized in that: The water washing kettle (1) is provided with a water washing kettle feed port (8), a primary material guide plate (14) is connected between the water washing kettle (1) and the drying box (2), and a magnet (15) is provided below the primary material guide plate (14).

3. The device for recovering waste heat from calcium oxide production according to claim 1, characterized in that: The vertical cooler (5) is provided with a cooler inner shell (9), the outer side of the cooler inner shell (9) is provided with a cooler outer shell (10), and the rotary kiln (4) is connected to the cooler inner shell (9) through a secondary material guide plate (16).

4. The device for recovering waste heat from calcium oxide production according to claim 1, characterized in that: The dust reduction heat exchange box (6) is provided with a dust reduction heat exchange box coil (11) inside, and the dust reduction heat exchange box coil (11) is connected to a dust reduction heat exchange box coil inlet pipe (18), and the dust reduction heat exchange box coil (11) is connected to the crushing and grinding box (3) through a dust reduction heat exchange box coil outlet pipe (19).

5. The device for recovering waste heat from calcium oxide production according to claim 1, characterized in that: The waste heat recovery water tank (7) is provided with a waste heat recovery water tank coil (13) inside, the induced draft fan (12) is connected to the waste heat recovery water tank coil (13) inside, and the waste heat recovery water tank (7) is connected to the washing kettle (1) through a liquid phase waste heat recovery water tank pipeline (20).

6. The device for recovering waste heat from calcium oxide production according to claim 1, characterized in that: The vertical cooler (5) is connected to the drying box (2) via a drying box inlet pipe (21), and a dust reduction heat exchange box inlet pipe (17) is connected between the rotary kiln (4) and the dust reduction heat exchange box (6).

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