Heat exchange device for sludge carbonization technology

[0022] In order to understand the above objects, features and advantages of the present invention more clearly, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that the embodiments of the present application and the features in the embodiments may be combined with each other in the case of no conflict.

[0023] In the description of the present invention, it should be noted that the terms "center", "portrait", "horizontal", "top", "bottom", "front", "rear", "left", "right", " The orientation or positional relationship indicated by vertical, horizontal, top, bottom, inner, outer, etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and The description is simplified rather than indicating or implying that the device or element referred to must have a particular orientation, be constructed and operate in a particular orientation, and therefore should not be construed as limiting the invention. Furthermore, the terms "first", "second", and "third" are used for descriptive purposes only and should not be construed to indicate or imply relative importance.

[0024] In the description of the present invention, it should be noted that, unless otherwise expressly specified and limited, the terms "connected" and "connected" should be understood in a broad sense, for example, it may be a fixed connection, a detachable connection, or an integral connection. Ground connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood in specific situations.

[0025] See figure 1 , the heat exchange device for the sludge carbonization process in this embodiment includes a front heat exchange unit and a rear heat exchange unit, the material outlet of the front heat exchange unit is connected to the material inlet of the reactor 10, and the rear heat exchange unit The material inlet of the reactor 10 is connected to the material outlet of the reactor 10 . The front heat exchange unit includes a plurality of front heat exchanger groups connected in parallel, and the plurality of the front heat exchanger groups work alternately, and/or the rear heat exchange unit includes a plurality of rear heat exchanger groups connected in parallel , and a plurality of the rear heat exchanger groups work alternately.

[0026] Among them, the function of the front heat exchanger group is to preheat the material entering the reactor 10, that is, the sludge, so that the sludge entering the reactor 10 can reach the set temperature. The set temperature here is generally but not limited. It is 50℃~80℃. The function of the rear heat exchanger group is to cool down the material output from the reactor 10, that is, the biochar, so that the biochar output from the rear heat exchanger group can be input into the subsequent pressure relief device.

[0027] The heat exchange device used for the sludge carbonization process in this embodiment includes multiple sets of heat exchangers (in this application, unless the heat exchanger sets are limited, they all refer to the front heat exchanger set and the / or rear heat exchanger group), so that when one of the heat exchanger groups conducts sufficient heat exchange for the material in it, the other heat exchanger groups can deliver the material that has undergone sufficient heat exchange to the subsequent stages of the sludge hydrothermal carbonization system. In the device, the material can pass through each group of heat exchangers smoothly and slowly, so as to ensure sufficient heat exchange between the material and the heat exchange medium in the heat exchanger group, so as to ensure a better heat exchange effect. In addition, since multiple heat exchanger groups work alternately, it is possible to ensure that the heat exchange device works continuously, so as to improve the heat exchange efficiency of the heat exchange device used for sludge carbonization in the process.

[0028] In addition, when the heat exchange device for the sludge carbonization process of the present embodiment works continuously, it can also improve the preheating recovery rate and achieve the effect of energy saving and environmental protection.

[0029] When the number of the current heat exchanger groups is multiple, the sludge entering the reactor 10 can be fully preheated, and the heat exchange efficiency of the heat exchange device used in the sludge carbonization process can be ensured. When the number of the rear heat exchanger groups is multiple, the biochar output from the reactor 10 can be sufficiently cooled, and the heat exchange efficiency of the heat exchange device used in the sludge carbonization process can be ensured.

[0030] However, the heat exchange device used for the sludge carbonization process in this embodiment not only includes a situation where the number of front heat exchanger groups or rear heat exchanger groups is multiple, but also includes a front heat exchanger group and a rear heat exchanger group. The number of are multiple. Preferably, the number of the front heat exchanger group and the rear heat exchanger group is plural, so as to have the above-mentioned beneficial effects.

[0031] Further, the front heat exchange unit includes a first inlet and a first outlet for circulation of heat exchange medium, and the rear heat exchange unit includes a second inlet and a second outlet for circulation of heat exchange medium.

[0032] For the purpose of environmental protection and energy saving, the first inlet is connected to the second outlet through a first pipeline, and the first outlet is connected to the second inlet, so that the front heat exchange unit and the rear heat exchange unit are connected. The first circulation loop of the heat exchange medium is formed between them. Therefore, after the heat exchange medium preheats the sludge in the front heat exchanger group, a heat exchange medium with a reduced temperature is obtained, and then the heat exchange medium with a reduced temperature is passed into the rear heat exchanger group to carry out the biochar treatment. Cool down. At the same time, the heat exchange medium in the rear heat exchanger group recovers the thermal energy of the biochar to obtain a heat exchange medium with an increased temperature. After that, the heat exchange medium whose temperature has been raised is passed into the front heat exchanger group to preheat the sludge, and so on.

[0033] The reason why the connection between the first inlet and the second outlet is limited through the first pipeline, and the connection between the first outlet and the second inlet is not limited, is mainly because the first pipeline needs to be further described later. .

[0034] In addition, the heat energy recovered by the rear heat exchanger group can not only be used to preheat the sludge, but also can be used to heat the auxiliary facilities of the factory in winter, so as to make full use of the remaining heat energy and achieve high efficiency and energy saving.

[0035] figure 1 There are two front heat exchanger groups and two rear heat exchanger groups. It should be noted that the attached figure 1 It does not constitute a limitation to this embodiment. In the heat exchange device used for the sludge carbonization process in this embodiment, the number of the front heat exchanger group and the rear heat exchanger group can be any other number.

[0036] In this embodiment, in order to realize the alternate work between the multiple front heat exchanger groups, it is preferable but not necessary that the material inlet of the front heat exchange unit is connected to the two front heat exchanger groups through the two first on-off valves 3 respectively. . In addition, a controller can be used to control the on-off of the first on-off valve 3 . Therefore, when the first switch valve 3 connected to the front heat exchanger group is turned on, the sludge can circulate in the front heat exchanger group and be transported to the subsequent reactor 10; the first switch connected to the front heat exchanger group When valve 3 is open, the sludge stays in this front heat exchanger bank for heating until its preheating is complete.

[0037] Of course, in order to realize the alternate work among multiple front heat exchanger groups, in addition to controlling the flow of materials through the first on-off valve 3, a second on-off valve 4 also needs to be set to control the flow of heat exchange medium.

[0038] from figure 1 It can be seen from the above that in this embodiment, two second on-off valves 4 are arranged at the first outlet position of the heat exchange medium of the front heat exchange unit, which are respectively connected to the two front heat exchanger groups, so that the corresponding When the second on-off valve 4 is turned on, the heat exchange medium can flow through the front heat exchanger group.

[0039] For a certain front heat exchanger group, if the first switch valve 3 is turned off, the second switch valve 4 corresponding to the front heat exchanger group is turned on at this time, so that the circulating heat exchange medium can exchange heat for the front heat exchanger group. The sludge in the reactor group is fully preheated. Conversely, if the first switch valve 3 of a certain front heat exchanger group is turned on, it means that the sludge in the front heat exchanger group is sufficiently preheated, and the second switch corresponding to the front heat exchanger group can be turned off at this time. valve 4.

[0040] Similarly, in order to realize the alternate work among multiple rear heat exchanger groups, the flow of materials can also be controlled by setting the first switch valve 3, and the flow of heat exchange medium can be controlled by setting the second switch valve 4. Wherein, there is also a certain connection between the on-off valve 3 and the second on-off valve 4 of the rear heat exchanger group, so as to realize the working alternation of multiple rear heat exchanger groups.

[0041] from figure 1 It can be seen from the above that the second switch valve 4 of the rear heat exchanger group is arranged at the second inlet of the heat exchange medium, of course, the second switch valve 4 can also be arranged at the second outlet of the heat exchange medium or other positions, as long as The flow of the heat exchange medium in the rear heat exchanger group may be controlled. Similarly, the setting positions of the first on-off valve 3 of the rear heat exchanger group, and the first on-off valve 3 and the second on-off valve 4 of the front heat exchanger group are not limited by the drawings, as long as the material or heat can be realized. The control of the exchange medium is sufficient.

[0042] And it should be noted that when the number of heat exchanger groups is other than two, the first on-off valve 3 and the second on-off valve 4 can also work alternately. The principle and the number of heat exchanger groups are two. The principle is the same at all times, and will not be repeated here.

[0043] Among them, it is preferable to switch the on-off of the first on-off valve 3 and the second on-off valve 4 corresponding to the heat exchanger group every 5-8 minutes, so as to control the alternation between the heat exchanger groups. In addition, a monitoring instrument may be provided corresponding to each heat exchanger to monitor the working state of each heat exchanger, and control the heat exchange device for the sludge carbonization process based on the monitoring results.

[0044] from figure 1 It can be seen from the above that in the front heat exchange unit of this embodiment, each front heat exchanger group includes three front heat exchangers 1, and along the material flow direction, there are a first-level front heat exchanger and a second-level front heat exchanger in sequence. and three-stage front heat exchanger.

[0045] Among them, "material flow direction" refers to the figure 1 The direction from left to right in the middle, so that the material finally passes into the reactor 10. Due to the staged preheating of the sludge by the primary front heat exchanger, the secondary front heat exchanger and the tertiary front heat exchanger, the primary front heat exchanger, the secondary front heat exchanger and the tertiary front heat exchanger The temperature of the sludge in the heat exchanger gradually increases, and finally the sludge output from the three-stage front heat exchanger reaches the set temperature. This method of grading heating can make the preheating of the sludge more sufficient and uniform, and can improve the heat exchange efficiency to achieve the purpose of energy saving, thereby improving the preheating effect from all aspects.

[0046] see further figure 1 , the first inlet of the front heat exchange unit is arranged on the side of the third-stage front heat exchanger, and the first outlet is arranged on the side of the first-stage front heat exchanger. Therefore, after the heat exchange medium enters from the first inlet, it passes through the three-stage front heat exchanger, the second-stage front heat exchanger and the first-stage front heat exchanger in sequence, and finally flows back from the first outlet on the side of the first-stage front heat exchanger. Rear heat exchange unit. In this case, the temperature of the heat exchange medium is the highest when it enters the three-stage front heat exchanger, and the temperature gradually decreases after passing through the two-stage front heat exchanger and the first-stage front heat exchanger, so as to meet the requirements of each front heat exchanger 1 for sludge preheating. hot request.

[0047] It can be seen from the above that in the front heat exchange unit, the sludge flows from left to right, while the heat exchange medium flows from right to left, that is, the flow direction of the material is opposite to the flow direction of the heat exchange medium, so that the material and the heat exchange medium are exchanged. Hot enough.

[0048] Of course, it should be noted that, in the front heat exchanger group of this embodiment, the number of the front heat exchangers 1 is not limited to three, and may be any number. The reason why three front heat exchangers 1 are selected in this embodiment is a preferred design scheme obtained by synthesizing multiple factors such as preheating effect and preheating efficiency.

[0049] Assuming that the material input to the front heat exchange unit has an initial temperature of 10°C to 30°C, and the final temperature of the material leaving the front heat exchange unit needs to reach 50°C to 80°C, then when the number of front heat exchangers 1 is three, each Each front heat exchanger 1 only needs to heat up the material by about 15°C.

[0050] further from figure 1 It can be seen from the above that in the rear heat exchange unit of this embodiment, each rear heat exchanger group includes six rear heat exchangers 2 connected in series. Exchanger, three-stage after heat exchanger, four-stage after heat exchanger, five-stage after heat exchanger and six-stage after heat exchanger.

[0051] In the same way, the "material flow direction" here refers to the figure 1 The direction from left to right in the middle, so that the material output from the reactor 10 enters the rear heat exchange unit, and is input into the pressure relief device through the rear heat exchange unit. Because the first-stage after heat exchanger, the second-stage after-heat exchanger, the third-stage after-heat exchanger, the fourth-stage after-heat exchanger, the fifth-stage after-heat exchanger and the sixth-stage after-heat exchanger are used for grading and cooling the sludge, The temperature of the biochar in the first-stage after heat exchanger, the second-stage after-heat exchanger, the third-stage after-heat exchanger, the fourth-stage after-heat exchanger, the fifth-stage after-heat exchanger and the sixth-stage after-heat exchanger gradually decreased, and finally the The biochar output from the six-stage rear heat exchanger reaches the set temperature. This method of grading cooling can make the cooling of biochar more thorough and uniform, and can improve the heat exchange efficiency to achieve the purpose of energy saving, so as to achieve the cooling effect in an all-round way.

[0052] see further figure 1 , the second inlet of the rear heat exchange unit is arranged on the side of the six-stage rear heat exchanger, and the second outlet is arranged on the side of the first-stage rear heat exchanger. Therefore, after the heat exchange medium enters from the second inlet, it sequentially passes through the six-stage rear heat exchanger, the fifth-stage rear heat exchanger, the fourth-stage rear heat exchanger, the third-stage rear heat exchanger, the second-stage rear heat exchanger and the first-stage rear heat exchanger. The rear heat exchanger finally flows back to the front heat exchange unit from the second outlet on the side of the primary rear heat exchanger. In this case, the temperature of the heat exchange medium is the highest when it enters the six-stage rear heat exchanger, and the temperature gradually decreases after passing through the subsequent rear heat exchangers 2, so as to meet the requirements for cooling the biochar in each of the rear heat exchangers 2.

[0053] It should be noted that, in addition to being arranged on the side of the sixth-stage rear heat exchanger, the second inlet can also be arranged between the sixth-stage rear heat exchanger and the fifth-stage rear heat exchanger, and the heat exchange medium enters through the second inlet. The five-stage rear heat exchanger, and then the fourth-stage rear heat exchanger, the third-stage rear heat exchanger, the second-stage rear heat exchanger, and the first-stage rear heat exchanger are sequentially entered. In this case, the first five-stage rear heat exchanger can be connected with the front heat exchange unit to form a closed loop, and the six-stage rear heat exchanger can use a different heat exchange medium from that in the closed loop. Preferably, water is used as the heat exchange medium in the six-stage rear heat exchanger, so that the temperature in the sixth-stage rear heat exchanger can be completely cooled, and the material output from the sixth-stage rear heat exchanger can meet the set requirements.

[0054] Similarly, in the rear heat exchange unit, the material flows from the rear heat exchanger 2 on the left to the rear heat exchanger 2 on the right, and the heat exchange medium flows from the rear heat exchanger 2 on the right to the rear heat exchanger 2 on the left. , that is, for the entire rear heat exchange unit, the flow direction of the material is opposite to the flow direction of the heat exchange medium, so that the heat exchange between the material and the heat exchange medium is sufficient. In addition, in the rear heat exchanger group of the present embodiment, the number of the rear heat exchangers 2 is not limited to six, and may be any number.

[0055] Wherein, according to the difference between the material temperature at the material outlet of the reactor 10 and the material temperature at the material outlet of the sixth-stage rear heat exchanger, the six-stage rear heat exchanger is selected and installed. It should be understood that the rear heat exchanger 2 is not limited to six stages.

[0056] In order to deal with the situation that the heat recovered in the rear heat exchange unit is not enough to preheat the sludge in the front heat exchange unit to the set temperature, between the secondary front heat exchanger and the tertiary front heat exchanger, close to the The secondary front heat exchanger is provided with a third inlet for the circulation of the heat exchange medium, and a third outlet is provided near the tertiary front heat exchanger. Of course, the third inlet can be directly arranged on the body of the secondary front heat exchanger, and the third outlet can also be directly arranged on the body of the tertiary heat exchanger.

[0057] The third inlet is connected to the second outlet through a second pipeline, so that a second circulation of heat exchange medium is formed between the first-stage front heat exchanger, the second-stage front heat exchanger and the rear heat exchange unit circuit, and the first pipeline and the second pipeline are alternately connected; the third outlet is connected to the first inlet through the third pipeline, so that the three-stage front heat exchanger itself forms heat The third circulation loop of the exchange medium.

[0058] When the heat recovered in the rear heat exchange unit is sufficient to fully preheat the sludge in the front heat exchange unit, the first pipeline is turned on and the second pipeline is disconnected, and the heat exchange medium flowing out from the rear heat exchange unit will enter The three-stage front heat exchanger, at this time, the heat exchange medium circulates in the first circulation loop formed by the connection of the entire front heat exchange unit and the rear heat exchange unit.

[0059]When the heat recovered in the rear heat exchange unit is not enough to fully preheat the sludge in the front heat exchange unit, the second pipeline is connected to the first pipeline and disconnected, and the heat exchange medium flowing out from the rear heat exchange unit Directly into the secondary front heat exchanger, and then into the primary front heat exchanger. For the three-stage front heat exchanger with higher temperature requirements, it is heated through the third circulation loop.

[0060] It can be seen from this that when the second pipeline is turned on, the third circulation loop is turned on; when the first pipeline is turned on, the third circulation loop is turned off.

[0061] See figure 1 , a third on-off valve 5 can be arranged on the first pipeline, so that the on-off of the first pipeline can be controlled by the on-off of the third on-off valve 5 . In addition, the on-off of the second pipeline can also be realized by a valve (attached figure 1 The valve provided on the second pipeline is not shown). When the second pipeline is conducting, in order to prevent the heat exchange medium in the third circulation loop from flowing into the secondary front heat exchanger, a fourth on-off valve 6 is provided between the third inlet and the third outlet, so that when When the first pipeline is disconnected and the second pipeline is connected, the fourth switch valve 6 is controlled to be disconnected; when the first pipeline is connected and the second pipeline is disconnected, the fourth switch valve 6 is controlled to be connected.

[0062] In order to make the third circulation loop have a heating effect, the third pipeline can be connected to the medium heat exchanger 9, and the medium heat exchanger 9 can be connected to the high-temperature heat exchange pipeline to the heat exchanger in the third pipeline. The heat exchange medium heats up. The medium heat exchanger 9 is different from the above-mentioned front heat exchanger 1 and rear heat exchanger 2, and its function is to heat up the heat exchange medium in the third pipeline.

[0063] from figure 1 It can be seen from the above that, in order to heat the materials in the reactor 10, a heat source device is arranged between the heating medium inlet and the heating medium outlet of the reactor 10. Specifically, the heating medium inlet is connected to the outlet of the heat source device, the heating medium outlet is connected to the return port of the heat source device through a fourth pipeline, and a circulating heating is formed between the reactor 10 and the heat source device loop.

[0064] In this embodiment, it is preferable that the high-temperature heat exchange pipeline and the fourth pipeline are connected in parallel, so that the high-temperature heat exchange pipeline adopts the heat source device for heating the reactor 10 as the heat source, and no additional heat source is required, so as to reduce the overall cost for the sludge carbonization process. The footprint of the heat exchange device.

[0065] In this embodiment, it is preferable that the heat source device is a heat-conducting oil furnace 11 , so that the heating medium entering the reactor 10 from the heat-conducting oil furnace 11 is heat-conducting oil. Also, it is preferable but not necessary that the medium in the front heat exchange unit and the rear heat exchange unit is also heat transfer oil. At this time, heat exchange between the heat transfer oil and the heat transfer oil is performed in the medium heat exchanger 9 connected to the third pipeline and the high temperature heat exchange pipeline.

[0066] In order to adjust the flow rate of the heat-conducting oil in the fourth pipeline and the high-temperature heat exchange pipeline, flow regulating valves 7 may be provided on the high-temperature heat exchange pipeline and the fourth pipeline, respectively. Preferably, the high temperature heat exchange pipeline is related to the flow regulating valve 7 on the fourth pipeline, so that when the opening degree of the flow regulating valve 7 on the high temperature heat exchange pipeline decreases, the opening degree of the flow regulating valve 7 on the fourth pipeline increases; When the opening degree of the flow regulating valve 7 on the high temperature heat exchange pipeline increases, the opening degree of the flow regulating valve 7 on the fourth pipeline decreases.

[0067] Furthermore, from figure 1 It can be found that each rear heat exchanger 2 is provided with an exhaust gas regulating valve 8 correspondingly, and the exhaust gas regulating valve 8 can be used to discharge the gas in the heat exchange medium. In addition, a pump 12 is provided on the circuit of the heat exchange medium for pumping the heat exchange medium.

[0068] attached figure 1 In order to distinguish the heat exchange medium, the heating medium and the material conveying pipeline, the first circulation loop, the second circulation loop and the third circulation loop of the heat exchange medium are represented by dotted lines, the circulating heating circuit is represented by dotted lines, and the material conveying Pipelines are represented by implementations.

[0069] In addition, when the heat exchanger of the prior art is suitable for heat exchange between sludge and biochar, it is prone to the phenomenon of material sticking. In addition, there are disadvantages such as poor fluidity, low heat exchange efficiency, and long heat exchange cycle. Therefore, the present embodiment proposes a new front heat exchanger 1 and a rear heat exchanger 2, and the front heat exchanger 1 and the rear heat exchanger 2 are described below respectively.

[0070] For the front heat exchanger 1 of this embodiment, please refer to figure 2 and image 3 , including a medium circulation pipe 13 and a material conveying pipe 14 arranged in the medium circulation pipe 13 . Among them, the heat exchange medium passes into the space between the medium circulation pipe 13 and the material conveying pipe 14 through the N1 port, and then flows out from the N2 port; the material passes into the material conveying pipe 14 through the N3 port, so that the heat exchange There is sufficient contact between the medium and the material, and then it is discharged from the N4 port.

[0071] Preferably, both the medium circulation pipe 13 and the material conveying pipe 14 are straight pipes, so as to reduce the resistance of the inner wall of the pipe to the material and the heat exchange medium. In addition, preferably but not necessarily, the medium circulation pipe 13 and the material conveying pipe 14 are both circular in cross section and made of 316L stainless steel.

[0072] from image 3 It can be seen from the above that, corresponding to the number of stages of the front heat exchanger 1, the number of material conveying pipes 14 set in one of the medium circulation pipes 13 is three. Since the number of material conveying pipes 14 in the medium circulation pipe 13 is larger, the material conveying capacity is weaker, but the thermal contact area between the material and the heat exchange medium is larger. In this embodiment, according to the characteristics of sludge, three material conveying pipes 14 are chosen to be arranged in the medium circulation pipe 13 to seek a reasonable balance between heat exchange efficiency and heat exchange effect. Of course, the number of material conveying pipes 14 is not subject to image 3 limits.

[0073] The above-mentioned front heat exchanger 1 is arranged horizontally, that is, the axes of the medium circulation pipe 13 and the material conveying pipe 14 are both located on the horizontal plane, thereby greatly reducing the resistance of material conveying.

[0074] For the rear heat exchanger 2 in this embodiment, please refer to Figure 4 and Figure 5 , and also includes a medium circulation pipe 13 and a material conveying pipe 14 arranged in the outer pipe.

[0075] The difference from the above-mentioned front heat exchanger 1 is that in the rear heat exchanger 2 of this embodiment, seven material conveying pipes 14 are arranged in the medium circulation pipes 13 . And, the rear heat exchanger 2 is placed vertically, so that for a single rear heat exchanger 2, the biochar is input from the top of the rear heat exchanger 2 and output from the bottom end of the rear heat exchanger 2; and the heat exchange medium is from the rear The bottom end of the heat exchanger 2 is input, and the top end of the rear heat exchanger 2 is output to ensure sufficient heat exchange between the biochar and the heat exchange medium.

[0076] The type of valve mentioned above is not limited, it can be any valve disclosed in the prior art.

[0077] The above embodiments are only used to illustrate the present invention, but not to limit the present invention. Although the present invention has been described in detail with reference to the embodiments, those of ordinary skill in the art should understand that various combinations, modifications or equivalent replacements to the technical solutions of the present invention do not depart from the spirit and scope of the technical solutions of the present invention, and should cover within the scope of the claims of the present invention.