Device for drying sludge by using exhaust gas

Abstract

The utility model discloses a device for drying sludge by using exhaust gas, which comprises a disc drying machine system, a sludge drying system and a sludge drying system, the sludge drying system sequentially passes through a gas heat exchanger, a sludge conveying device and a cold water heat exchanger through cooperation of exhaust gas and circulating air, and the sludge in the sludge conveying device is subjected to a circulating sludge drying process; and the exhaust gas treatment system is used for treating the cooled exhaust gas. According to the waste heat utilization device, waste heat utilization can be carried out on exhaust gas needing to be discharged originally, energy is saved, and the cost of original exhaust gas treatment equipment is reduced; exhaust gas generated in the disc drying machine system is reutilized through the sludge drying system, the sludge is circularly dried in cooperation with circulating air, the overall energy consumption is low, and a large amount of sludge treatment cost can be saved.

Description

Technical Field

[0001] The utility model relates to the technical field of sludge drying, in particular to a device for drying sludge by utilizing exhaust gas. Background Art

[0002] Disc dryer is a kind of equipment commonly used for sludge drying. It evaporates the water in the sludge through heating and rotating motion, turning it into a solid state. It is widely used in sewage treatment plants, environmental protection projects, metallurgy, chemical industry, mining and other fields to treat and dry sludge. It can effectively reduce the volume and weight of sludge, making it convenient for subsequent treatment and disposal.

[0003] In the direct heat exchange process involving heat sources such as steam or flue gas, such as the sludge drying production process of the disc dryer, the heat source will be converted into low-temperature steam or flue gas (100°C) with many impurities after contacting the material. This low-temperature steam or flue gas containing impurities is usually called exhaust gas. In order to treat this exhaust gas, it is usually necessary to add processing equipment at the exhaust gas outlet to cool and dehumidify it, and then return it to the boiler system as combustion air after treatment. However, the heat energy contained in these exhaust gases is not effectively utilized, but needs to be processed through facilities such as cooling towers, resulting in energy waste. Utility Model Content

[0004] The purpose of the utility model is to solve the above problems and provide a device for drying sludge by utilizing exhaust gas.

[0005] In order to achieve the above-mentioned purpose, the utility model specifically adopts the following technical solutions, including:

[0006] A disc dryer system, wherein the disc dryer system is used for carrying out a sludge drying process;

[0007] The sludge drying system comprises a sludge conveying device, a gas heat exchanger and a cold water heat exchanger are arranged above the sludge conveying device, and the sludge in the sludge conveying device is subjected to a circulating sludge drying process by exhaust gas and circulating air passing through the gas heat exchanger, the sludge conveying device and the cold water heat exchanger in sequence.

[0008] As a further description of the above technical solution, it also includes a waste gas treatment system, which includes a cooling and dehumidification device and a boiler device, and the waste gas treatment system is used to treat the waste gas after cooling.

[0009] As a further description of the above technical solution, the cooling and dehumidifying device is connected to the gas outlet of the gas heat exchanger, and the cooling and dehumidifying device is used to cool and dehumidify the exhaust gas.

[0010] As a further description of the above technical solution, the boiler device is connected to the air outlet of the cooling and dehumidification device, and the boiler device is used to process the exhaust gas after low-temperature drying.

[0011] As a further description of the above technical solution, the disc dryer system and the gas heat exchanger are connected via a heat exchange pipe, and a control valve is also provided on the heat exchange pipe.

[0012] As a further description of the above technical solution, conveyor belts are evenly distributed at heights inside the sludge conveying device, and 3-5 groups of conveyor belts are provided.

[0013] As a further description of the above technical solution, an air inlet is provided at the bottom of one side of the sludge conveying device, and an air outlet is provided on the upper side of the sludge conveying device. The circulating air flows into the air inlet from the gas heat exchanger and then flows out from the air outlet to the cold water heat exchanger.

[0014] As a further description of the above technical solution, a feeding device is also provided on one side above the sludge conveying device, and the feeding device is used to convey the sludge to the conveyor belt.

[0015] As a further description of the above technical solution, the gas heat exchanger is arranged on one side of the upper end of the sludge conveying device, and the gas heat exchanger cooperates with the exhaust gas generated by the disc dryer system and the circulating air circulating in the sludge conveying device to perform a heat exchange process.

[0016] As a further description of the above technical solution, the cold water heat exchanger is arranged on one side of the gas heat exchanger, and the cold water heat exchanger cooperates with the circulating air circulating in the sludge conveying device to perform a condensation and drainage process.

[0017] The beneficial effects of the utility model are as follows:

[0018] 1. The utility model can save energy and reduce the operating cost of the original exhaust gas treatment equipment by utilizing the waste heat of the exhaust gas that originally needs to be discharged. In the sludge drying system, the exhaust gas generated by the disc dryer system can be reused for a second time, and the sludge can be dried in a circulating air process, which can effectively reduce the overall energy consumption, improve energy utilization efficiency, and also save a lot of sludge treatment costs.

[0019] In order to more clearly illustrate the structural features and functions of the present invention, the present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a structural schematic diagram of the utility model sludge drying device;

[0021] Reference numerals:

[0022] 1. Disc dryer system; 11. Control valve; 2. Sludge drying system; 21. Sludge conveying device; 211. Conveyor belt; 212. Air inlet; 213. Air outlet; 22. Gas heat exchanger; 23. Cold water heat exchanger; 24. Feeding device; 3. Exhaust gas treatment system; 31. Cooling and dehumidification device; 32. Boiler device. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solution and advantages of the embodiments of the present utility model clearer, the technical solution in the embodiments of the present utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the present utility model.

[0024] like Figure 1 As shown, in one embodiment, a device for drying sludge using exhaust gas includes: a disc drying system 1, a sludge drying system 2, and an exhaust gas treatment system 3. The disc drying system 1 is used to perform the sludge drying process, and the sludge drying system 2 sequentially passes the disc drying system 1 through a gas heat exchanger 22, a sludge conveying device 21, and a cold water heat exchanger 23 with circulating air to achieve cyclic drying treatment of the sludge in the sludge conveying device; the exhaust gas treatment system 3 is used to treat the exhaust gas after cooling.

[0025] Furthermore, the disc dryer system 1 and the gas heat exchanger 22 are connected via a heat exchange pipe, and a control valve 11 is also provided on the heat exchange pipe to ensure that the flow of the exhaust gas can be effectively controlled during the operation of the system.

[0026] like Figure 1 As shown, in this embodiment, 3-5 groups of conveyor belts 211 are evenly arranged inside the sludge conveying device 21 according to the height. Among them, an air inlet 212 is provided at the bottom of one side of the sludge conveying device 21, and an air outlet 213 is provided at one side of the upper end. The circulating air flows from the gas heat exchanger 22 into the air inlet 212, passes through the conveyor belt 211 area, and finally flows from the air outlet 213 to the cold water heat exchanger 23.

[0027] Furthermore, a feeding device 24 is provided on the upper side of the sludge conveying device 21 for conveying the sludge to the conveyor belt 211 to achieve smooth conveying and drying of the sludge.

[0028] like Figure 1As shown, in this embodiment, a gas heat exchanger 22 and a cold water heat exchanger 23 are arranged above the sludge conveying device 21. The gas heat exchanger 22 is located on one side of the upper end of the sludge conveying device 21, and is used to perform a heat exchange process with the exhaust gas generated by the disc dryer system 1 and the circulating air circulating in the sludge conveying device 21. The cold water heat exchanger 23 is located on one side of the gas heat exchanger 22, and performs a condensation and drainage process with the circulating air circulating in the sludge conveying device 21.

[0029] like Figure 1 As shown, in this embodiment, the exhaust gas treatment system 3 includes a cooling and dehumidifying device 31 and a boiler device 32. The cooling and dehumidifying device 31 is connected to the gas outlet of the gas heat exchanger 22, and is used to cool and dehumidify the exhaust gas. The boiler device 32 is connected to the gas outlet of the cooling and dehumidifying device 31, and is mainly responsible for processing the exhaust gas after low-temperature drying.

[0030] Working principle:

[0031] The disc dryer system will produce 100°C exhaust gas during the drying process. The exhaust gas is introduced into the gas heat exchanger 22 to play an indirect heating role. The circulating air of the sludge drying system 2 is heated by the gas heat exchanger 22 to form 70°C circulating air. The feeding device 24 inputs the sludge into the sludge drying system 2 and evenly distributes it on the multi-layer conveyor belt 211. The circulating air takes out the water vapor in the sludge through the conveyor belt 211 covered with sludge, forming humid hot air of about 55°C. The humid hot air passes through the cold water heat exchanger 23, and the water vapor in it is condensed and discharged. After it becomes 40°C dry cold air, it enters the gas heat exchanger 22 again for heating, completing the entire cycle. After the dryer circulating air is heated by the gas heat exchanger 22, the heat of the exhaust gas in the gas heat exchanger 22 is absorbed, so that the 100°C exhaust gas is cooled to 80°C and then discharged from the gas heat exchanger 22, and then enters the cooling and dehumidification system to be cooled to 50°C, and finally enters the boiler system to be used as combustion-supporting air.

[0032] By reusing the exhaust gas generated by the disc dryer system in the sludge drying system 2 and combining it with the circulating air to dry the sludge, the overall energy consumption can be effectively reduced, the energy utilization efficiency can be improved, and a large amount of sludge treatment costs can be saved at the same time, thus achieving energy conservation and reducing the operating costs of the exhaust gas treatment equipment.

[0033] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A device for drying sludge using exhaust gas, characterized in that: include: A disc drying machine system (1), wherein the disc drying machine system (1) is used for carrying out a sludge drying process; A sludge drying system (2), the sludge drying system (2) comprising a sludge conveying device (21), a gas heat exchanger (22) and a cold water heat exchanger (23) being arranged above the sludge conveying device (21), the exhaust gas being matched with the circulating air passing through the gas heat exchanger (22), the sludge conveying device (21) and the cold water heat exchanger (23) in sequence, so as to perform a circulating sludge drying process on the sludge in the sludge conveying device.

2. The device for drying sludge using exhaust gas according to claim 1, characterized in that: It also includes a waste gas treatment system (3), wherein the waste gas treatment system (3) includes a cooling and dehumidifying device (31) and a boiler device (32), and the waste gas treatment system (3) is used to treat the waste gas after cooling.

3. The device for drying sludge using exhaust gas according to claim 2, characterized in that: The cooling and dehumidifying device (31) is connected to the gas outlet of the gas heat exchanger (22), and the cooling and dehumidifying device (31) is used to cool and dehumidify the exhaust gas.

4. The device for drying sludge using exhaust gas according to claim 2, characterized in that: The boiler device (32) is connected to the gas outlet of the cooling and dehumidifying device (31), and the boiler device (32) is used to process the exhaust gas after low-temperature drying.

5. The device for drying sludge using exhaust gas according to claim 1, characterized in that: The disc drying machine system (1) and the gas heat exchanger (22) are connected via a heat exchange pipeline, and a control valve (11) is also provided on the heat exchange pipeline.

6. The device for drying sludge using exhaust gas according to claim 1, characterized in that: Conveyor belts (211) are evenly distributed at different heights inside the sludge conveying device (21), and 3 to 5 groups of the conveyor belts (211) are provided.

7. The device for drying sludge using exhaust gas according to claim 1, characterized in that: An air inlet (212) is provided at the bottom of one side of the sludge conveying device (21), and an air outlet (213) is provided at the upper end of the sludge conveying device (21); the circulating air flows from the gas heat exchanger (22) into the air inlet (212) and then flows out from the air outlet (213) to the cold water heat exchanger (23).

8. The device for drying sludge using exhaust gas according to claim 1, characterized in that: A feeding device (24) is also provided on one side above the sludge conveying device (21), and the feeding device (24) is used to convey the sludge to the conveyor belt (211).

9. The device for drying sludge using exhaust gas according to claim 1, characterized in that: The gas heat exchanger (22) is arranged on one side of the upper end of the sludge conveying device (21), and the gas heat exchanger (22) cooperates with the exhaust gas generated by the disc dryer system (1) and the circulating air circulating in the sludge conveying device (21) to perform a heat exchange process.

10. The device for drying sludge using exhaust gas according to claim 1, characterized in that: The cold water heat exchanger (23) is arranged on one side of the gas heat exchanger (22), and the cold water heat exchanger (23) cooperates with the circulating air circulating in the sludge conveying device (21) to perform a condensation and drainage process.

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