Potassium chloride drying system equipment

Abstract

The utility model discloses potassium chloride drying system equipment which comprises feeding equipment, microwave drying equipment, a flue gas pipeline, a cyclone dust collector, a tail gas pipeline and a water bath dust collector, the feeding equipment conveys materials to a material conveying belt of the microwave drying equipment, and the materials are output after being dried by the microwave drying equipment; a gas collecting hood is arranged at the top of the microwave drying equipment, the gas collecting hood is communicated with a gas inlet of the cyclone dust collector through a flue gas pipeline, and a gas outlet of the cyclone dust collector is communicated with the interior of the water bath dust collector through a tail gas pipeline. Compared with the prior art, the microwave drying equipment is adopted for drying the potassium chloride wet matter, the amount of smoke after microwave drying is reduced, the follow-up collection and dust removal load is reduced, the yield of potassium chloride is improved compared with traditional drying, cooling equipment does not need to be additionally arranged, and the production cost is reduced. The temperature of the dried potassium chloride can meet the packaging requirement through natural cooling, and potassium chloride dust and water vapor in tail gas can be recycled through a water bath dust remover.

Description

Technical Field

[0001] The utility model relates to the field of chemical industry, and in particular to a potassium chloride drying system equipment. Background Art

[0002] China is a large agricultural country. The three major fertilizers required for crops are nitrogen, phosphorus and potash fertilizers, and potassium chloride occupies a major market share in potash fertilizers. The production of potassium chloride using carnallite and sylvite as raw materials is divided into two categories: hot and cold processing. Regardless of the process route, the finished potassium chloride needs to be dried and dehumidified before packaging. Because potassium chloride is hygroscopic, it is easy to absorb moisture, dissolve and precipitate on its surface during storage and transportation, resulting in the formation of new crystals between salt particles, leading to the occurrence of agglomeration, which seriously affects product quality.

[0003] The national standard requires that the water content of industrial potassium chloride should be controlled below 2%, while the water content of potassium chloride produced by the general flotation method is about 9%-10%, which needs further drying. The traditional drying process is to make the flue gas temperature after natural gas combustion reach (500-600℃) and contact with wet potassium chloride in the rotary dryer to dry the finished potassium chloride. To ensure the removal of moisture, the tail gas temperature needs to be maintained at 110℃. At this time, the temperature of the dried potassium chloride is 80-100℃. The dried product needs to enter the rotary cooler to cool to 40℃ before entering the subsequent packaging process. The dried tail gas is separated and dusted by the cyclone dust collector group, and then enters the pulse bag dust collector for secondary dust removal. After the product in the air is recovered through two dust removals, the flue gas is discharged into the atmosphere.

[0004] This drying process not only has high drying temperature and complex procedures, but also requires the recovery of products in the flue gas. Therefore, only a cyclone dust collector and a bag dust collector can be used for dry dust removal, and potassium chloride products can be recovered by dust removal. Due to the structure of the bag dust collector and the moisture content in the flue gas, the temperature of the 110°C flue gas entering the bag dust collector after passing through the cyclone is reduced. Especially in winter, the heat loss is large and condensation will occur. Since potassium chloride has strong hygroscopicity, it will block the bag, resulting in a significant increase in operating resistance, affecting the dust removal efficiency, and causing the bag to wear, perforate and fall off, shortening its life and increasing maintenance costs. In severe cases, the bag dust collector needs to be isolated for maintenance, which will affect production and the environment.

[0005] Moreover, if the dust removal measures adopted for the dust-containing flue gas generated during the dry drying process are unreasonable, it will not only reduce the potassium chloride yield, but also have a great impact on the pollution of the surrounding atmospheric environment. Utility Model Content

[0006] The purpose of the utility model is to provide a potassium chloride drying system equipment that solves the above-mentioned problem, through which the floated wet potassium chloride is dried for storage and transportation.

[0007] In order to achieve the above-mentioned purpose, the technical solution adopted by the utility model is: a potassium chloride drying system equipment, including a feeding device, a microwave drying device, a flue gas duct, a cyclone dust collector, an exhaust gas duct and a water bath dust collector, the feeding device conveys the material to the feeding belt of the microwave drying device, and the material is output after being dried by the microwave drying device, and an air collecting hood is provided on the top of the microwave drying device, the air collecting hood is connected with the air inlet of the cyclone dust collector through the flue gas duct, and the air outlet of the cyclone dust collector is connected with the inside of the water bath dust collector through the exhaust gas duct.

[0008] Preferably, a plurality of exhaust ports are provided on the top of the microwave drying device, and the exhaust ports are arranged in sequence and at intervals along the length direction of the microwave drying device, and the microwave drying device is connected to the interior of the gas collecting hood through the exhaust ports.

[0009] Preferably, a product recovery port is provided at the bottom of the cyclone dust collector.

[0010] Preferably, a plurality of gas distributors are arranged in sequence from bottom to top at the bottom of the water bath dust collector, and the gas distributors are all connected to the exhaust gas pipeline.

[0011] Preferably, a plurality of atomizing spray devices are sequentially arranged on the upper part of the water bath dust collector from top to bottom, and the atomizing spray devices are connected through a spray pipeline.

[0012] Preferably, a solution recovery pipe is provided at the bottom of the water bath dust collector.

[0013] Compared with the prior art, the advantages of the utility model are:

[0014] (1) The utility model adopts microwave drying equipment to dry wet potassium chloride. The amount of flue gas after microwave drying is reduced, which reduces the subsequent dust collection load. At the same time, the yield of potassium chloride is improved compared with traditional drying. The potassium chloride dust content in the flue gas is low. Through the lower drying temperature, the energy used is greatly reduced, which reduces the operating cost. The dust removal equipment required is smaller than the dust removal equipment for flue gas after traditional drying, and the cost is low.

[0015] (2) The temperature of the dried potassium chloride can meet the packaging requirements by natural cooling, without the need for cooling equipment, thus shortening the process line. The shorter process reduces the one-time cost of the equipment.

[0016] (3) The use of a water bath dust collector can not only recycle a small amount of potassium chloride dust in the tail gas, but also condense the water vapor in the tail gas and recycle it, reducing the flue gas emissions. In addition, the recovered potassium chloride solution can be used in the potassium chloride production line, solving the problem of requiring a large amount of water-soluble materials in the potassium chloride production process. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a system principle block diagram of the utility model.

[0018] In the figure, 1. feeding equipment; 2. microwave drying equipment; 3. gas collecting hood; 4. flue gas duct; 5. cyclone dust collector; 6. tail gas duct; 7. water bath dust collector; 8. atomizing spray device; 9. gas distributor; 10. spray pipeline; 11. solution recovery pipe. DETAILED DESCRIPTION

[0019] The utility model will be further described below.

[0020] A potassium chloride drying system equipment, see Figure 1 , including a feeding device 1, a microwave drying device 2, a flue gas duct 4, a cyclone dust collector 5, an exhaust gas duct 6 and a water bath dust collector 7. The feeding device 1 conveys the material to the feeding belt of the microwave drying device 2, and the material is output after being dried by the microwave drying device 2. An air collecting hood 3 is provided on the top of the microwave drying device 2. The air collecting hood 3 is connected with the air inlet of the cyclone dust collector 5 through the flue gas duct 4, and the air outlet of the cyclone dust collector 5 is connected with the inside of the water bath dust collector 7 through the exhaust gas duct 6.

[0021] Since the dielectric constant of water is 80, it is highly sensitive to microwaves, while the dielectric constant of potassium chloride is 4.6, which is relatively small compared to water, and is hardly heated during the microwave drying process. According to a large amount of simulation test data comparison and analysis, in order to achieve drying efficiency, the utility model uses microwave drying equipment 2 to dry the wet potassium chloride flotated. During microwave drying, the moisture requirement of potassium chloride wet material feeding needs to be controlled before 4.5-10%, which is consistent with the moisture content of wet material at the front end of the current potassium chloride drying process. After drying, the moisture content is less than 2%, which can meet the moisture requirements of industrial potassium chloride products. At the same time, the morphology and structure of potassium chloride dried by microwaves have not changed. Through experiments, it is found that the optimal temperature for microwave drying of potassium chloride is 55-65°C, and the possibility of microwave drying being applied to wet potassium chloride lays the foundation for the engineering design of potassium chloride drying process in the future. The amount of flue gas after drying by microwave drying equipment 2 is less than that of traditional gas flue gas drying, which reduces the subsequent collection and dust removal load, and at the same time improves the yield of potassium chloride compared with traditional drying. The temperature of potassium chloride after drying can meet the packaging requirements by natural cooling, and no cooling equipment needs to be added, shortening the process flow line.

[0022] Although the microwave drying equipment 2 achieves low-temperature drying, there is still a small amount of potassium chloride dust in the flue gas. Therefore, a plurality of exhaust ports are opened on the top of the existing microwave drying equipment 2. The exhaust ports are arranged in sequence at intervals along the length direction of the microwave drying equipment 2. The microwave drying equipment 2 is connected to the inside of the gas collecting hood 3 through the exhaust ports. The flue gas is collected through the gas collecting hood 3 so as to recover the potassium chloride dust in the flue gas as a product.

[0023] A product recovery port is provided at the bottom of the cyclone dust collector 5, and potassium chloride dust products are recovered through the cyclone dust collector 5.

[0024] Due to the use of microwave drying equipment 2, the load of subsequent collection of potassium chloride dust is reduced. The cyclone dust collector 5 can collect most of the potassium chloride dust, so there is no need to use a bag dust collector for dust recovery, which solves various problems of bag collection of potassium chloride dust. However, the exhaust gas discharged from the outlet of the cyclone dust collector 5 still contains a small amount of potassium chloride dust.

[0025] Therefore, the utility model is connected in series with a water bath dust collector 7 at the outlet of the cyclone dust collector 5, and a plurality of gas distributors 9 are sequentially arranged along the tower body from bottom to top in the water bath dust collector 7, and the gas distributors 9 are all connected with the tail gas pipeline 6. A plurality of atomizing spray devices 8 are sequentially arranged on the upper part of the water bath dust collector 7 from top to bottom, and the atomizing spray devices 8 are connected through a spray pipeline 10. The tail gas containing potassium chloride dust enters the lower part of the cylinder of the water bath dust collector 7, and rises evenly through the atomizing spray device 8 after passing through the gas distributor 9, and contacts with the water mist sprayed in the reverse direction. Under the collision, interception and condensation of dust particles and droplets, the potassium chloride dust is absorbed and dissolved, and the gas and water exchange heat at the same time. Then the gas continues to rise and is discharged to high altitude through the chimney on the top of the tower. The potassium chloride solution that completes the mass heat exchange is returned to the potassium chloride production system from the solution recovery pipe 11 at the bottom of the water bath dust collector 7 for recycling.

[0026] The utility model not only improves the dust removal process, but also discharges a large amount of water in the traditional dry flue gas into the air. The potassium chloride production process requires a large amount of water-soluble materials. The use of the water bath dust collector 7 not only recycles the water, but also reduces the flue gas emissions and energy consumption. It should be noted that when using the water bath dust collector 7 to treat flue gas containing potassium chloride dust, special attention should be paid to the selection of towers, smoke exhaust chimneys and air duct materials. Because halogen-containing salts are very corrosive to metal materials, especially Cl - The design of the internal structure of the water bath dust collector 7 is very important for the distribution of gas. Whether the gas distribution is uniform will directly affect the dust removal effect.

[0027] The above is a detailed introduction to a potassium chloride drying system equipment and process provided by the utility model. Specific examples are used in this article to illustrate the principle and implementation method of the utility model. The description of the above embodiments is only used to help understand the method and core idea of ​​the utility model; at the same time, for those skilled in the art, according to the idea of ​​the utility model, there will be changes in the specific implementation method and application scope, and changes and improvements to the utility model will be possible without exceeding the concept and scope specified in the attached claims. In summary, the content of this specification should not be understood as a limitation on the utility model.

Claims

1. A potassium chloride drying system equipment, characterized in that: It includes a feeding device, a microwave drying device, a flue gas duct, a cyclone dust collector, an exhaust gas duct and a water bath dust collector. The feeding device conveys the material to the feeding belt of the microwave drying device, and the material is output after being dried by the microwave drying device. An air collecting hood is provided on the top of the microwave drying device, and the air collecting hood is connected with the air inlet of the cyclone dust collector through the flue gas duct. The air outlet of the cyclone dust collector is connected with the inside of the water bath dust collector through the exhaust gas duct.

2. A potassium chloride drying system equipment according to claim 1, characterized in that: A plurality of exhaust ports are arranged on the top of the microwave drying device, and the exhaust ports are arranged in sequence and at intervals along the length direction of the microwave drying device. The microwave drying device is connected with the interior of the gas collecting hood through the exhaust ports.

3. A potassium chloride drying system equipment according to claim 1, characterized in that: A product recovery port is provided at the bottom of the cyclone dust collector.

4. A potassium chloride drying system equipment according to claim 1, characterized in that: A plurality of gas distributors are arranged in sequence from bottom to top at the bottom of the water bath dust collector, and the gas distributors are all connected to the exhaust gas pipeline.

5. A potassium chloride drying system equipment according to claim 1, characterized in that: A plurality of atomizing spray devices are sequentially arranged on the upper part of the water bath dust collector from top to bottom, and the atomizing spray devices are connected through a spray pipeline.

6. A potassium chloride drying system equipment according to claim 1, characterized in that: A solution recovery pipe is provided at the bottom of the water bath dust collector.

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