High-humidity material tail gas recycling and drying system

Abstract

The utility model discloses a high-humidity material tail gas recycling and drying system, which relates to the technical field of tail gas recycling and drying and comprises a double-layer rotary dryer, a high-temperature heater, a high-efficiency gas-solid separator, a high-pressure circulating fan and a heat recycling device, a material inlet of the double-layer rotary dryer is connected with a feeding device, and a material outlet of the double-layer rotary dryer is connected with a spiral discharging machine. The circulating drying medium inlet is connected with the high-temperature heater, the circulating drying medium outlet is connected with the gas-solid separator, a gas outlet of the gas-solid separator is connected with an air suction port of the high-pressure circulating fan, and an exhaust port of the high-pressure circulating fan is connected with the high-temperature heater. The double-layer rotary drum dryer is reasonable in structural design, materials are dried through superheated steam which is generated by the high-temperature heater and exceeds the temperature of a drying speed reversal point, compared with a traditional drying mode, energy consumption can be saved by more than half, the double-layer rotary drum dryer is adopted, the materials are arranged on the inner layer, and circulating drying media are arranged on the outer layer. Condensation caused by contact between the surface of the roller and wet materials is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of tail gas recovery and drying systems, in particular to a tail gas recovery and drying system for high-humidity materials. Background Art

[0002] In the existing technology, high-humidity material drying is usually carried out by using high-temperature flue gas or high-temperature hot air generated by hot air furnaces burning coal, oil, gas or biomass to dry high-humidity materials. The water vapor and gas generated by the drying materials are purified by the tail gas purification device and then discharged. As the water in the materials evaporates during the drying of high-humidity materials, a large amount of water vapor will be generated. As the tail gas is discharged, a large amount of white plume (white smoke) will appear in the chimney of the drying system, causing serious visual pollution.

[0003] Since the exhaust gas contains a large amount of non-condensable gases in addition to water vapor, the cost of exhaust gas recovery is relatively high. The latent heat of water vapor in the exhaust gas is difficult to recover, and the gas volume is large, so the exhaust gas purification cost is also high.

[0004] Some high-humidity materials such as animal manure, sludge, kitchen waste, bacterial protein, bone meal, food waste and other materials with a certain odor will produce a lot of unwelcome odors when dried using traditional methods. Moreover, due to the large amount of gas, the odor is difficult to handle and has an impact on the environment.

[0005] Some high-humidity materials, such as wine lees, forage grass, straw, palm fiber, sawdust, fungus residue, starch residue, etc., are flammable and explosive after drying. Using traditional drying methods, high-temperature flue gas or hot air can easily cause the dryer to catch fire and explode.

[0006] Publication No. CN104896903B discloses a biomass material drying system with full exhaust gas recovery. The waste heat heating silo is connected to a screw feeder with a closed structure through a waste heat heating feeder. The hot water pipe is located below the waste heat heating silo. The high temperature tubes of the main machine are on the side of the container-type tube heating drum main machine. The secondary heater is located above the high temperature tube container of the main machine. The highly sealed circulation fan is located on the side of the secondary heater outside the container. This application adopts a container-type tube heating drum main machine, which integrates high temperature heating and material drying. The heating is carried out inside the container-type drum. The high temperature is easy to cause fire and carbonize the material. The drum surface is easy to produce condensation when it contacts the wet material. Summary of the invention

[0007] The utility model aims to solve the above technical problems and provide a high-humidity material tail gas recovery and drying system.

[0008] In order to achieve the above technical objectives and meet the above technical requirements, the technical solution adopted by the utility model is: a high-humidity material tail gas recovery and drying system, which is characterized by: comprising a double-layer rotary drum dryer, a high-temperature heater, a high-efficiency gas-solid separator, a high-pressure circulating fan, and a heat recovery device. The double-layer rotary drum dryer is provided with a material inlet, a material outlet, a circulating drying medium inlet, and a circulating drying medium outlet. The material inlet is connected to the feeding device, the material outlet is connected to the spiral discharging machine, the circulating drying medium inlet is connected to the high-temperature heater through a pipeline, the circulating drying medium outlet is connected to the gas-solid separator through a pipeline, the gas outlet of the gas-solid separator is connected to the air intake of the high-pressure circulating fan through a pipeline, the solid outlet of the gas-solid separator is connected to the spiral discharging machine, the exhaust port of the high-pressure circulating fan is connected to the high-temperature heater through a pipeline, and the heat recovery device is used to recover heat from excess water vapor.

[0009] Preferably: the double-layer rotary drum dryer comprises an inner drum and an outer drum, an interlayer is arranged between the inner drum and the outer drum, the wet material is located in the inner drum, a gap is arranged on the inner drum, and the circulating drying medium heated by the high-temperature heater enters the inner drum through the interlayer and the gap to exchange heat and mass with the wet material to dry the wet material.

[0010] Preferably, the inner cylinder is configured as a conical cylinder or a straight cylinder.

[0011] Preferably, the circulating drying medium is circulating superheated steam, and the material is dried by generating superheated steam having a temperature exceeding a drying rate reversal point through a high temperature heater.

[0012] Preferably, the high temperature heater is configured as an anti-blocking high temperature heater, thereby preventing the dust in the circulating drying medium from affecting the equipment.

[0013] Working principle: The wet material enters the double-layer rotary dryer through the feeding device. The circulating drying medium heated by the high-temperature heater exchanges heat and quality with the wet material in the double-layer rotary dryer, so that the wet material is dried. The circulating drying medium after heat exchange is dedusted by the high-efficiency gas-solid separator, circulated to the high-temperature heater for heating and then circulated again through the high-pressure circulating fan. The heat recovery device is used to recover heat from excess water vapor.

[0014] Compared with the traditional structure, the utility model has the following beneficial effects:

[0015] 1. The utility model has a reasonable structural design and adopts a double-layer rotary drum dryer. The material is in the inner layer and the circulating drying medium is in the outer layer, which avoids condensation caused by the contact of the drum surface with the wet material; the circulating drying medium directly contacts the material for heat and quality exchange, effectively protecting the material and avoiding carbonization of the material.

[0016] 2. The utility model has good economic efficiency and is more energy-saving. Since the drying medium is circulating superheated water vapor, the water vapor generated by the evaporation of water in the high-humidity material is basically in a saturated state, and it is easy to recover heat through a heat recovery device and turn it into liquid water for discharge. Compared with the traditional drying method, its energy consumption can be saved by more than half, which greatly improves the economy of drying high-humidity materials. At the same time, it avoids the generation of a large amount of non-condensable gas in the traditional drying method, and basically can achieve no white plume (white smoke) emissions.

[0017] 3. The utility model has high safety, adopts an independently set anti-blocking high-temperature heater and a double-layer rotary drum dryer, circulates superheated water vapor as a drying medium, and basically can achieve air-free, that is, oxygen-free, in the drying system, solving the problem of easy fire and explosion in traditional drying methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the structure of the utility model;

[0019] Figure 2 This is a schematic diagram of the structure of the double-layer rotary drum drying machine of the utility model;

[0020] In the figure: 1. double-layer rotary drum dryer, 11. outer drum, 12. inner drum, 2. high-temperature heater, 3. gas-solid separator, 4. high-pressure circulation fan, 5. heat recovery device, 6. spiral discharger. DETAILED DESCRIPTION

[0021] The utility model is further described below.

[0022] Combined with Figure 1 The high-humidity material tail gas recovery and drying system comprises a double-layer rotary dryer 1, a high-temperature heater 2, a high-efficiency gas-solid separator 3, a high-pressure circulating fan 4, and a heat recovery device 5. The double-layer rotary dryer 1 is provided with a material inlet, a material outlet, a circulating drying medium inlet, and a circulating drying medium outlet. The material inlet is connected to the feeding device, the material outlet is connected to the spiral discharging machine 6, the circulating drying medium inlet is connected to the high-temperature heater 2 through a pipeline, the circulating drying medium outlet is connected to the gas-solid separator 3 through a pipeline, the gas outlet of the gas-solid separator 3 is connected to the air intake of the high-pressure circulating fan 4 through a pipeline, the solid outlet of the gas-solid separator 3 is connected to the spiral discharging machine 6, the exhaust port of the high-pressure circulating fan 4 is connected to the high-temperature heater 2 through a pipeline, and the heat recovery device 5 is used to recover heat from excess water vapor.

[0023] As attached Figure 2As shown, the double-layer rotary drum dryer 1 includes an inner drum 12 and an outer drum 11, wherein an interlayer is provided between the inner drum 12 and the outer drum 11, and the wet material is located in the inner drum 12. A gap is provided on the inner drum 12, and the circulating drying medium heated by the high-temperature heater 2 enters the inner drum through the interlayer and the gap to exchange heat and mass with the wet material to dry the wet material.

[0024] The inner cylinder 12 is configured as a conical cylinder or a straight cylinder, and the inner cylinder 12 is connected to the outer cylinder 11 via a gap. The drying medium first passes through the interlayer between the outer cylinder 11 and the inner cylinder 12, and then enters the inner cylinder 12 through the gap to contact the wet material. At the same time, the high temperature of the drying medium in the interlayer can prevent the wet material from contacting the outer cylinder to produce condensation.

[0025] The circulating drying medium is circulating superheated steam, and the superheated steam with a temperature exceeding the drying rate reversal point is generated by the high temperature heater 2 to dry the material instead of traditional flue gas and hot air.

[0026] The high temperature heater 3 is configured as an anti-blocking high temperature heater, thereby preventing the dust in the circulating drying medium from affecting the equipment.

[0027] The heat source used by the anti-blocking high temperature heater can be gas, oil, biomass, methane, superheated steam, electricity and other heat sources.

[0028] In specific implementation, the high-humidity material passes through the feeding device and enters the inner drum 12 of the double-layer rotary dryer 1. At the same time, the circulating superheated steam heated by the anti-blocking high-temperature heater 2 passes through the inner and outer drum interlayer of the double-layer rotary dryer 1, and then passes through the gap on the inner drum 12 to enter the inner drum 12, contacting the wet material for heat and mass exchange, so that the wet material can be dried. The saturated steam coming out of the double-layer rotary dryer 1 passes through the high-efficiency gas-solid separator 3 for dust removal, circulates to the anti-blocking high-temperature heater 2 for heating, and then enters the double-layer rotary dryer 1 to complete the cycle. The dried material and the material separated by the gas-solid separator are discharged through the spiral discharging machine 6. With the double-layer rotary dryer 1, the wet material is in the inner layer and the circulating superheated steam is in the outer layer, which avoids the condensation phenomenon caused by the contact between the drum surface and the wet material; the circulating superheated steam directly contacts the material for heat and mass exchange, effectively protecting the material and avoiding carbonization of the material.

[0029] Excess water vapor is recovered through the latent heat recovery device to achieve energy saving. The excess water vapor generated by the high-humidity material tail gas recovery and drying system has high latent heat and is very convenient to recover heat through the condensation recovery device.

[0030] Since the drying medium is circulating superheated steam, the water vapor generated by the evaporation of water in the high-humidity material is basically in a saturated state, and it is easy to recover heat through a heat recovery device and turn into liquid water for discharge. Compared with traditional drying methods, its energy consumption can be saved by more than half, greatly improving the economy of drying high-humidity materials. At the same time, it avoids the generation of a large amount of non-condensable gas in traditional drying methods, and basically can achieve no white plume (white smoke) emissions.

[0031] The above embodiments of the present invention are merely examples to clearly illustrate the present invention, but are not intended to limit the protection scope of the present invention. All equivalent technical solutions also belong to the scope of the present invention. The patent protection scope of the present invention should be defined by the claims.

Claims

1. High-humidity material tail gas recovery and drying system, characterized by: The invention comprises a double-layer rotary drum dryer (1), a high-temperature heater (2), a gas-solid separator (3), a high-pressure circulating fan (4), and a heat recovery device (5). The double-layer rotary drum dryer (1) is provided with a material inlet, a material outlet, a circulating drying medium inlet, and a circulating drying medium outlet. The material inlet is connected to a feeding device, the material outlet is connected to a spiral discharger (6), the circulating drying medium inlet is connected to the high-temperature heater (2) through a pipeline, the circulating drying medium outlet is connected to the gas-solid separator (3) through a pipeline, the gas outlet of the gas-solid separator (3) is connected to the air intake of the high-pressure circulating fan (4) through a pipeline, the solid outlet of the gas-solid separator (3) is connected to the spiral discharger (6), the exhaust port of the high-pressure circulating fan (4) is connected to the high-temperature heater (2) through a pipeline, and the heat recovery device (5) is used to recover heat from excess water vapor.

2. The high-humidity material tail gas recovery and drying system according to claim 1 is characterized by: The double-layer rotary drum dryer (1) comprises an inner drum (12) and an outer drum (11); an interlayer is provided between the inner drum (12) and the outer drum (11); wet materials are located in the inner drum (12); a gap is provided on the inner drum (12); a circulating drying medium heated by a high-temperature heater (2) enters the inner drum (12) through the interlayer and the gap, and exchanges heat and quality with the wet materials to dry the wet materials.

3. The high-humidity material tail gas recovery and drying system according to claim 2 is characterized in that: The inner cylinder (12) is configured as a conical cylinder or a straight cylinder.

4. The high-humidity material tail gas recovery and drying system according to claim 1 is characterized in that: The circulating drying medium is circulating superheated steam, and the high-temperature heater (2) generates superheated steam having a temperature exceeding the drying rate reversal point to dry the material.

5. The high-humidity material tail gas recovery and drying system according to claim 1 is characterized in that: The high temperature heater (2) is configured as an anti-blocking type high temperature heater.

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