Sludge drying device with waste heat recovery function
By introducing a steam ejector and a flash tank into the sludge drying unit, the separation and reuse of saturated steam and condensate were achieved, solving the problems of steam resource waste and unit vibration, and improving steam utilization and unit stability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-20
- Publication Date
- 2026-03-10
AI Technical Summary
In existing sludge drying equipment, the saturated steam after heat exchange cannot be reused, which causes vibration to the condensate delivery pipeline and heat exchanger, affecting the normal operation of the equipment and wasting steam resources.
A steam ejector and a flash evaporator are introduced into the sludge drying unit. The saturated steam after heat exchange is reused through the Laval tube effect of the steam ejector, and the saturated steam and condensate are separated in the flash evaporator. The condensate is collected in the condensate collection tank, which improves the utilization rate of steam resources and prevents vibration.
This enables the reuse of steam resources, avoids vibration of the condensate delivery pipeline, ensures stable operation of the unit, and reduces steam waste.
Smart Images
Figure CN223983581U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model belongs to sludge drying technical field, concretely relates to a sludge drying device with waste heat recovery function. BACKGROUND
[0002] With the acceleration of coal chemical industry, a large amount of industrial wastewater will be produced in chemical plant production, and the biochemical method is applied to treat industrial wastewater has become an important means, but a large amount of activated sludge will be produced in the process of treating industrial wastewater, in order to reduce the moisture content of sludge and remove the pollution components, the sludge plays a crucial role after dewatering, in the sludge drying process using steam as heat source, how to reduce steam consumption has become an important problem.
[0003] In the sludge drying project using steam as heat source, according to the original process flow, steam heat exchange will produce steam and condensate mixture, wherein there is still a large amount of saturated steam, in the condensate recovery and disposal process, the mixed saturated steam will cause vibration to condensate delivery pipeline and heat exchanger, affect the normal operation of the device, and also cause waste of steam resources. UTILITY MODEL CONTENTS
[0004] Therefore, the utility model discloses a sludge drying device with waste heat recovery function, solves the problem that saturated steam cannot be reused after heat exchange in the prior art sludge drying device, saturated steam causes vibration to condensate delivery pipeline and heat exchanger, affects the normal operation of the device, and also causes waste of steam resources.
[0005] In order to realize the above-mentioned purpose, the technical scheme adopted by the utility model is as follows:
[0006] A sludge drying device with waste heat recovery function, comprising a drying box, a heat exchanger and wet sludge needing drying treatment are arranged in the drying box, high-temperature steam is introduced into the heat exchanger to exchange heat with air, and then the wet sludge placed in the drying box is dried, characterized in that the sludge drying device further comprises:
[0007] A steam ejector is used to deliver steam to the heat exchanger, the steam ejector comprises a connecting pipe and a working pipe in communication, a first air inlet and a second air inlet are arranged on the connecting pipe, a first air outlet is arranged on the working pipe, the first air inlet is in communication with an external steam source, the direction of the first air inlet and the first air outlet is on the same straight line, the direction of the first air outlet is perpendicular to the direction of the first air inlet, in addition, the pipe body diameter of the two ends of the working pipe is greater than the pipe body diameter of the middle part of the working pipe, and the first air outlet is in communication with the heat exchanger through a first pipeline;
[0008] A flash evaporation tank is located on one side of the drying chamber. The top of the flash evaporation tank is connected to the heat exchanger inside the drying chamber via a second pipe. This connection is used to introduce the heat-exchanged steam into the flash evaporation tank for the separation of saturated steam and condensate. The saturated steam is located on the upper inside of the flash evaporation tank, and the condensate is located on the lower inside of the flash evaporation tank. In addition, the side wall of the flash evaporation tank near the top is connected to the second air inlet of the steam ejector via a third pipe.
[0009] A condensate collection tank is located on one side of the flash evaporation tank. One side of the condensate collection tank is connected to the bottom of the flash evaporation tank via a fourth pipe for collecting the condensate in the flash evaporation tank. One side of the condensate collection tank is connected to a condensate pipeline network.
[0010] Preferably, the steam source provides low-pressure steam, and the temperature of the low-pressure steam is 150°C, and the pressure of the low-pressure steam is approximately 0.5 MPa.
[0011] Furthermore, the steam ejector is equipped with valves at the location near the first air inlet and on the third pipe, which are used to control the amount of steam entering the steam ejector and the amount of saturated steam recovered after heat exchange, respectively.
[0012] Preferably, the pressure inside the flash evaporation tank is atmospheric pressure, 0.1 MPa.
[0013] Preferably, the fourth pipeline is also equipped with a suction pump for sending the condensate in the flash tank into the condensate collection tank for collection.
[0014] The beneficial effects of this utility model are as follows:
[0015] In general, this invention connects a flash evaporation tank to the heat exchanger of an existing sludge drying device. The flash evaporation tank separates the saturated steam and condensate after heat exchange. The condensate in the flash evaporation tank is then collected in a condensate collection tank. In addition, this invention also installs a steam ejector at the steam input end of the heat exchanger and uses the Laval tube effect of the steam ejector to reintroduce the steam from the flash evaporation tank into the heat exchanger for reuse. This improves the utilization rate of steam resources and prevents the steam from causing vibration to the condensate delivery pipeline, thus avoiding affecting the overall operation of the device. Attached Figure Description
[0016] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0017] Figure 1 This is a schematic diagram of the overall structure of this utility model;
[0018] Figure 2 This is a schematic diagram of the specific structure of the steam ejector in this utility model. Detailed Implementation
[0019] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0020] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model; the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance. In addition, unless otherwise explicitly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two components. For those skilled in the art, the specific meaning of the above terms in this utility model can be understood according to the specific circumstances.
[0021] The technical solution of this application will be described in detail below with reference to the accompanying drawings.
[0022] The device includes a drying chamber, which contains a heat exchanger and wet sludge to be dried. High-temperature steam is introduced into the heat exchanger to exchange heat with air, thereby drying the wet sludge placed inside the drying chamber. The sludge drying device further includes:
[0023] In this technical solution, such as Figure 1As shown, a sludge drying device with waste heat recovery function mainly includes a drying box 1, which contains a heat exchanger and wet sludge to be dried. The main working principle of the sludge drying device is to exchange heat with the air by introducing high-temperature steam into the heat exchanger, thereby drying the wet sludge placed inside the drying box 1. The drying box 1 and the heat exchanger are incorporated into this utility model, and their specific structures are not described in detail here. In addition, the sludge drying device also includes a steam ejector 2, a flash evaporation tank 3, and a condensate collection tank 4.
[0024] Specifically, such as Figures 1-2 As shown, the steam ejector 2 is used to supply steam to the heat exchanger 1. The steam ejector 2 includes an integrally connected connecting pipe 201 and a working pipe 202. The connecting pipe 201 is provided with a first air inlet 203 and a second air inlet 204. The working pipe 202 is provided with a first air outlet 205. The first air inlet 203 is connected to an external steam source, and the low-pressure steam provided by the steam source has a temperature of 150°C and a pressure of 0.5 MPa. In addition, the directions of the first air inlet 203 and the first air outlet 205 are on the same straight line. The direction of the second air inlet 204 is perpendicular to the direction of the first air inlet 203. Furthermore, the diameter of the pipe body at both ends of the working pipe 202 is larger than the diameter of the pipe body in the middle of the working pipe 202. The first air outlet 205 is connected to the heat exchanger in the drying chamber 1 through a first pipe 5. The steam emitted by the external steam source is introduced into the heat exchanger through the cooperation of the steam ejector 2 and the first pipe 5.
[0025] In addition, such as Figure 1 As shown, the flash evaporation tank 3 is located on one side of the drying chamber 1. The top of the flash evaporation tank 3 is connected to the heat exchanger inside the drying chamber 1 through the second pipe 6. The pressure inside the flash evaporation tank 3 is atmospheric pressure 0.1 MPa. Since the steam after heat exchange is a mixture of saturated steam and condensate, when it is introduced into the flash evaporation tank 3 with reduced pressure, the saturated steam will separate from the condensate. Therefore, the flash evaporation tank 3 is used to introduce the steam mixture after heat exchange into the flash evaporation tank 3 to separate the saturated steam and condensate. Specifically, the saturated steam is located on the upper side of the flash evaporation tank 3, and the condensate is located on the lower side of the flash evaporation tank 3. In addition, the side wall of the flash evaporation tank 3 near the top is also connected to the second air inlet 204 of the steam ejector 2 through the third pipe 7, so that the saturated steam located on the upper side of the flash evaporation tank 3 can be reintroduced into the heat exchanger.
[0026] It should be noted here that, for ease of description, in the direction from the first inlet 203 to the first outlet 205 of the steam ejector 2, the portion of the working pipe 202 with a gradually decreasing diameter is configured as the suction mixing section, and the portion with a gradually increasing diameter is configured as the pressurization and diffusion section. With the steam ejector 2 configured as described above, the pressure energy of the steam fed into the first inlet 203 through the steam source is converted into kinetic energy using the Laval tube effect, forming a supersonic jet. The steam carried by this jet is primarily fluid steam. When the primarily fluid steam moves within the suction mixing section of the working pipe 202 with a gradually decreasing diameter, it passes through the second inlet 204. The second inlet 204, the third pipe 7, and the steam in the flash tank 3 are configured as the pumped fluid steam. The extracted fluid steam is injected into the suction mixing section due to the strong shearing action between it and the main fluid steam. The turbulent diffusion effect of the boundary layer of the main fluid steam causes the two fluid steams to exchange momentum and energy. As a result, the velocity of the main fluid steam continuously decreases, while the velocity of the extracted fluid steam continuously increases, and they gradually become consistent at a certain cross section of the suction mixing section, thus forming a single uniform mixed fluid steam. After the mixed fluid steam enters the pressurization and diffusion section, the kinetic energy of the mixed fluid steam is converted back into pressure energy due to the gradually increasing structure of the pipe body. The mixed fluid steam is decelerated and pressurized again to 0.5 MPa and then discharged from the steam ejector 2 through the first outlet 205. Under the action of the first pipe 5, the mixed fluid steam is input into the heat exchanger for heat exchange.
[0027] Based on the above embodiments, the steam ejector 2 is configured so that the saturated steam after heat exchange can be reused, thereby improving the utilization rate of steam resources. In addition, the present invention also provides valves at the position of the steam ejector 2 near the first air inlet 203 and on the third pipe 7, for controlling the amount of steam entering the steam ejector 2 and the amount of saturated steam recovered after heat exchange, respectively.
[0028] In this technical solution, such as Figure 1 As shown, a condensate collection tank 4 is located on one side of a flash evaporator 3. One side of the condensate collection tank 4 is connected to the bottom of the flash evaporator 3 via a fourth pipe 8, which is used to pass the condensate in the flash evaporator 3 into the condensate collection tank 4 for collection. One side of the condensate collection tank 4 is connected to a condensate pipeline network. In addition, a suction pump 801 is also provided on the fourth pipe 8, which is used to send the condensate in the flash evaporator 3 into the condensate collection tank 4 for collection.
[0029] Specifically, this invention connects the heat exchanger 1 of the existing sludge drying device to a flash evaporation tank 3, and uses the flash evaporation tank 3 to separate the saturated steam and condensate after heat exchange. Then, the condensate in the flash evaporation tank 3 is passed into a condensate collection tank 4 for collection. In addition, this invention also installs a steam ejector 2 at the steam input end of the heat exchanger in the drying chamber 1, and uses the Laval tube effect of the steam ejector 2 to pass the saturated steam in the flash evaporation tank 3 back into the heat exchanger 1 for reuse. This improves the utilization rate of steam resources and also prevents the mixture of steam and condensate from causing vibration to the condensate delivery pipeline, thus avoiding affecting the overall operation of the device.
[0030] Finally, it should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Although the present utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.
Claims
1. A sludge drying device with waste heat recovery function, comprising a drying box, a heat exchanger and wet sludge to be dried in the drying box, air is heated by passing high-temperature steam into the heat exchanger, and then the wet sludge placed in the drying box is dried, characterized in that, The sludge drying device further comprises: a steam ejector for delivering steam to the heat exchanger, the steam ejector comprising a connecting pipe and a working pipe in integral communication, the connecting pipe being provided with a first gas inlet and a second gas inlet, the working pipe being provided with a first gas outlet, wherein the first gas inlet is in communication with an external steam source, the direction of the first gas inlet and the first gas outlet are on the same line, the direction of the second gas inlet is perpendicular to the direction of the first gas inlet, in addition, the pipe body diameter of the two ends of the working pipe is greater than the pipe body diameter of the middle part of the working pipe, and the first gas outlet is in communication with the heat exchanger through a first pipeline; a flash tank arranged on one side of the drying box, the top of the flash tank being in communication with the heat exchanger in the drying box through a second pipeline, for delivering the saturated steam separated from the condensed liquid in the flash tank, the saturated steam being located on the upper side of the inside of the flash tank, and the condensed liquid being located on the lower side of the inside of the flash tank, in addition, the side wall of the flash tank is connected to the second gas inlet of the steam ejector through a third pipeline at a position close to the top; a condensed liquid collecting tank arranged on one side of the flash tank, one side of the condensed liquid collecting tank being in communication with the bottom of the flash tank through a fourth pipeline, for delivering the condensed liquid in the flash tank into the condensed liquid collecting tank for collection, and one side of the condensed liquid collecting tank being connected to a condensed liquid pipeline network.
2. The sludge dewatering device with waste heat recovery function according to claim 1, characterized in that: The steam source provides low-pressure steam, and the temperature of the low-pressure steam is 150°C, and the pressure of the low-pressure steam is 0.5Mpa.
3. The sludge dewatering device with waste heat recovery function according to claim 2, characterized in that: The steam ejector is provided with a valve at a position close to the first gas inlet and on the third pipeline, for respectively controlling the steam entering amount of the steam ejector and the recovery amount of the saturated steam after heat exchange.
4. The sludge dewatering device with waste heat recovery function according to claim 3, characterized in that: The pressure in the flash tank is normal pressure 0.1Mpa.
5. The sludge dewatering device with waste heat recovery function according to claim 4, characterized in that: The fourth pipeline is further provided with a suction pump for delivering the condensed liquid in the flash tank into the condensed liquid collecting tank for collection.