Condenser for diazinon production

Abstract

A condenser for diazinon production relates to the field of condensing equipment for chemical engineering and comprises a plurality of cylindrical graphite heat exchange blocks and an outer cylinder for accommodating the graphite heat exchange blocks, the graphite heat exchange blocks are sequentially arranged into a group from top to bottom, transverse through holes and vertical through holes are densely distributed in each graphite heat exchange block, the transverse through holes serve as refrigerant channels, and the vertical through holes serve as vertical through holes. The vertical through holes in the graphite heat exchange blocks are connected end to end to serve as a heating medium channel, the heating medium circulates, heat in the heating medium is conducted into the refrigerant through graphite materials, first sealing grooves are machined in the end faces of the graphite heat exchange blocks, the first sealing grooves are in a circular ring shape, and O-shaped sealing rings are arranged in the first sealing grooves. The vertical through holes are divided into an inner group and an outer group by the first sealing grooves. The heat medium channels are divided into two groups, so that return flowing of the heat medium in the heat medium channels is realized, the flow speed of the heat medium is increased through return flowing, and the convective heat transfer coefficient is increased, so that the heat exchange efficiency is effectively improved, and the condensation speed is increased.

Description

Technical Field

[0001] The invention belongs to the field of condensing equipment for chemical industry, and in particular relates to a condenser used for diazinon production. Background Art

[0002] The block hole graphite condenser (heat exchanger) is a special condensing equipment necessary in the production process of diazinon. It has strong corrosion resistance and good thermal conductivity, and can meet the heat exchange requirements in the production process of diazinon.

[0003] In the traditional block-hole graphite condenser (heat exchanger), there are several cylindrical graphite heat exchange blocks, each of which is covered with horizontal and vertical through holes, and the horizontal through holes and vertical through holes are staggered. After the graphite heat exchange blocks are stacked into a cylinder, the vertical through holes on each graphite heat exchange block are connected in series to form a group of long through holes that run through from top to bottom, which serve as the channel for the condensed corrosive medium, called the heat medium channel. The heat medium channel is connected to the upper and lower ends of the block-hole graphite condenser; an annular space is left between the outer side of each graphite heat exchange block and the outer wall of the block-hole graphite condenser (heat exchanger). The annular space is connected to the horizontal through holes on each graphite heat exchange block and serves as a channel for the cooling medium, called the refrigerant channel. During condensation, the condensed corrosive medium and the cooling medium flow through the heat medium channel and the refrigerant channel respectively, and the heat is conducted through the graphite material to achieve heat exchange condensation.

[0004] The existing block hole graphite condenser (heat exchanger) has the following technical problems: The graphite heat exchange block is cut into a three-dimensional grid structure by horizontal and vertical through holes at various locations, resulting in poor structural strength. At the same time, graphite is a brittle material, and the internal stress caused by the temperature difference between the refrigerant and the heat medium may cause brittle cracks inside the graphite heat exchange block, further weakening the structural strength of the graphite heat exchange block.

[0005] For a long time, technicians have tried to develop polymer materials with better performance for impregnation treatment in order to improve the structural strength of graphite heat exchange blocks. However, the present invention takes a different approach and hopes to improve the structural strength of graphite heat exchange blocks by improving their structure. Summary of the invention

[0006] The present invention provides a condenser for diazinon production, which improves the existing block hole type graphite condenser, especially optimizes the design of the graphite heat exchange block inside the condenser to enhance the structural strength of the graphite heat exchange block, and at the same time improves the heat exchange efficiency of the block hole type graphite condenser and increases the condensation speed.

[0007] The technical problem solved by the present invention is achieved by the following technical solution: The present invention provides a condenser for diazinon production, comprising a plurality of cylindrical graphite heat exchange blocks and an outer cylinder for accommodating the graphite heat exchange blocks, wherein the graphite heat exchange blocks are sequentially arranged in a group from top to bottom, and each graphite heat exchange block is densely covered with transverse through holes and vertical through holes, wherein the transverse through holes serve as refrigerant channels for the circulation of refrigerant, and the vertical through holes on each graphite heat exchange block are connected end to end and serve as heat medium channels for the circulation of heat medium, and the heat in the heat medium is conducted to the refrigerant through the graphite material to realize heat exchange condensation; A circular ring-shaped area without vertical through holes is arranged on the upper end surface of the graphite heat exchange block, and vertical through holes are arranged on both inner and outer sides of the circular ring-shaped area.

[0008] As a preferred embodiment, a first sealing groove is machined in the annular area on the upper end surface of the graphite heat exchange block. The first sealing groove is annular and has an O-ring disposed therein. The vertical through holes are divided into two groups, inner and outer, by the first sealing groove. During operation, the heat medium first flows through a group of vertical through holes on one side of the first sealing groove, and then flows through a group of vertical through holes on the other side of the first sealing groove after turning back.

[0009] As a preferred solution, the upper and lower ends of the graphite heat exchange block group are respectively provided with an upper head and a lower head made of graphite material, and the upper head is provided with a heat medium inlet and a heat medium outlet; The upper and lower ends of the outer cylinder are respectively connected with an upper cover and a lower cover corresponding to the upper head and the lower head.

[0010] As a preferred solution, the upper cover is slidably mounted on the upper end of the outer cylinder, and the upper head is attached to the graphite heat exchange block below it under the elastic force of the spring.

[0011] As a preferred solution, a refrigerant inlet and a refrigerant outlet are provided on the side of the outer cylinder.

[0012] As a preferred embodiment, a baffle is arranged between the graphite heat exchange block and the outer cylinder, the number of the baffles is the same as the number of the graphite heat exchange blocks, and the baffles are alternately arranged on the left or right side of each graphite heat exchange block from top to bottom, so that the transverse through holes in each graphite heat exchange block are connected end to end to form a serpentine flow channel.

[0013] As a preferred solution, the first sealing groove is concentric with the outer diameter of the graphite heat exchange block.

[0014] As a preferred solution, the first sealing groove is not concentric with the outer diameter of the graphite heat exchange block.

[0015] The beneficial effects of the present invention are: 1. The present invention provides an annular area without vertical through holes in the vertical through hole array on the graphite heat exchange block. Since there are no vertical through holes in this area, the structural strength of the entity in this area is significantly enhanced compared with other areas. The stronger annular area is equivalent to the skeleton in the graphite heat exchange block. The skeleton support function is more able to withstand the pressure from the upper and lower sides of the graphite heat exchange block, so that the graphite heat exchange block is not easily damaged by pressure.

[0016] In addition, in order to adapt to the thermal expansion and contraction of the graphite heat exchange block, the upper head in the present invention is installed in a floating manner. After adopting this installation method, the maximum pressure that the O-rings between the graphite heat exchange blocks can seal depends on the preload force of the spring, and the upper limit of the spring preload force depends on the ability of the graphite heat exchange block to withstand pressure from both sides. In the present invention, the setting of the annular area without vertical through holes significantly improves the ability of the graphite heat exchange block to withstand pressure from both sides, thereby allowing the preload force of the spring to be set larger, and ultimately significantly improving the maximum pressure that the O-rings between the graphite heat exchange blocks can seal, thereby improving the pressure bearing capacity of the condenser.

[0017] 2. The annular area is a unique structure in the present invention. On the basis of this unique structure, the present invention sets a first sealing groove and an O-ring in the annular area. The heat medium channel is divided into two groups by the O-ring, thereby realizing the return flow of the heat medium in the heat medium channel. The return flow increases the flow rate of the heat medium and increases the convective heat transfer coefficient, thereby effectively improving the heat exchange efficiency and increasing the condensation speed.

[0018] 3. In the present invention, the first sealing groove can be made non-concentric with the outer diameter of the graphite heat exchange block, that is, the first sealing groove can be made biased toward one side of the end face of the graphite heat exchange block. Such a design can make room on the outside of the first sealing groove so that the heat medium outlet can be set at the top of the upper head, and then the heat medium flows out of the heat medium channel and directly flows upward to the heat medium outlet. Compared with the first embodiment in which the heat medium outlet is set on the side of the upper head, the flow resistance of the heat medium can be significantly reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the overall structure of the first embodiment of the present invention.

[0020] Figure 2 yes Figure 1 Schematic diagram of the structure of the top of the graphite heat exchange block.

[0021] Figure 3 yes Figure 2 Left view of .

[0022] Figure 4 yes Figure 3 Cross-sectional view at BB in the middle.

[0023] Figure 5 yes Figure 2 Cross-sectional view at AA in the middle.

[0024] Figure 6 It is a schematic diagram of the overall structure of the second embodiment of the present invention.

[0025] Figure 7 yes Figure 6 Schematic diagram of the structure of the top of the graphite heat exchange block.

[0026] Figure 8 yes Figure 7 Cross-sectional view at CC.

[0027] Fig. 9 It is a schematic diagram of the distribution of vertical through holes on the top of a graphite heat exchange block in the prior art.

[0028] Fig.10 yes Fig. 9 Left view of .

[0029] Figure 1 Middle: 1. Upper cover; 2. Upper head; 3. Heat medium inlet; 4. Spring; 5. Graphite heat exchange block; 6. Outer cylinder; 7. Lower head; 8. Lower cover; 9. Refrigerant outlet; 10. Baffle; 11. Refrigerant inlet; 12. Heat medium outlet; 13. Heat medium channel; 14. Horizontal through hole; 15. Vertical through hole; 16. First sealing groove; 17. Second sealing groove. DETAILED DESCRIPTION

[0030] The present invention is further described below in conjunction with the accompanying drawings.

[0031] First embodiment like Figure 1-10 As shown, this embodiment includes a plurality of cylindrical graphite heat exchange blocks 5 and an outer tube 6 for accommodating the graphite heat exchange blocks 5. The graphite heat exchange blocks 5 are arranged in a group from top to bottom. Each graphite heat exchange block 5 is densely covered with transverse through holes 14 and vertical through holes 15. The transverse through holes 14 serve as refrigerant channels for the circulation of refrigerant. The vertical through holes 15 on each graphite heat exchange block 5 are connected end to end as heat medium channels 13 for the circulation of heat medium. The heat in the heat medium is transferred to the refrigerant through the graphite material to achieve heat exchange condensation. The above is a conventional structure in the prior art and will not be repeated here.

[0032] like Figure 2As shown, the upper end surface of the graphite heat exchange block 5 is provided with an annular region without vertical through holes 15, and both the inner and outer sides of the annular region are provided with vertical through holes 15. Since there are no vertical through holes 15 in the annular region, the structural strength of the entity in this region is significantly enhanced compared with other regions. The stronger annular region is equivalent to the skeleton in the graphite heat exchange block 5, and its skeleton support function is more able to withstand the pressure from the upper and lower sides of the graphite heat exchange block 5, so that the graphite heat exchange block 5 is not easily damaged by pressure.

[0033] like Figure 2 As shown, in this embodiment, on the upper end surface of the graphite heat exchange block 5, a first sealing groove 16 is processed in the annular area, the first sealing groove 16 is annular, and an O-ring is arranged inside it. The vertical through hole 15 is divided into two groups, inner and outer, by the annular first sealing groove 16, and isolated and sealed by the O-ring.

[0034] In this embodiment, a second sealing groove 17 is provided at the edge of the upper end surface of the graphite heat exchange block 5 , and an O-ring is also provided in the second sealing groove 17 , and the edges of the upper and lower graphite heat exchange blocks 5 are sealed by the O-ring.

[0035] like Figure 2 As shown, in this embodiment, the upper and lower ends of the graphite heat exchange block 5 group are respectively provided with an upper head 2 and a lower head 7 which are also made of graphite material, and the upper head 2 is provided with a heat medium inlet 3 and a heat medium outlet 12. The upper head 2, the lower head 7 and each graphite heat exchange block 5 are connected to form a continuous heat medium flow path which is completely made of graphite (impregnated graphite), and the corrosive heat medium is confined in the space surrounded by the graphite material, thereby avoiding corrosion damage to the condenser.

[0036] like Figure 2 As shown, in this embodiment, the upper and lower ends of the outer cylinder 6 are respectively connected with an upper cover 1 and a lower cover 8 corresponding to the upper head 2 and the lower head 7, which are used to protect the upper head 2 and the lower head 7 and provide rigid support for the upper head 2 and the lower head 7.

[0037] like Figure 1 As shown, in this embodiment, a refrigerant inlet 11 and a refrigerant outlet 9 are provided on the side of the outer tube 6 .

[0038] Working principle: During operation, after the refrigerant flows in from the refrigerant inlet 11, it enters the annular space between the graphite heat exchange block 5 and the outer cylinder 6, then flows through the transverse through holes 14 on each graphite heat exchange block 5, and finally flows out from the refrigerant outlet 9. At the same time, after the heat medium flows in from the heat medium inlet 3, it first flows through a group of vertical through holes 15 on the inner side of the first sealing groove 16, reaches the lower head 7 and turns back, then flows through a group of vertical through holes 15 on the outer side of the first sealing groove 16, and finally flows out from the heat medium outlet 12. By dividing the heat medium channel 13 into two groups, the return flow of the heat medium in the heat medium channel 13 is realized. Through the return flow, the flow rate of the heat medium is increased, and the convective heat transfer coefficient is increased, thereby effectively improving the heat exchange efficiency and increasing the condensation speed.

[0039] like Figure 1 As shown, in this embodiment, the upper cover 1 is slidably mounted on the upper end of the outer cylinder 6, and the upper head 2 is attached to the graphite heat exchange block 5 below it under the elastic force of the spring 4. Such a design allows the upper head 2 and the upper cover 1 to slide elastically with the thermal expansion and contraction of the graphite heat exchange block 5, thereby preventing the graphite heat exchange block 5, the upper head 2 and the lower head 7 from being crushed. In addition, after the upper head 2 adopts the above-mentioned installation method, the maximum pressure that the O-type sealing ring between each graphite heat exchange block 5 can seal depends on the preload force of the spring 4, and the upper limit of the preload force of the spring 4 depends on the ability of the graphite heat exchange block 5 to withstand pressure from both sides. In the present invention, the setting of the annular area without vertical through holes 15 significantly improves the ability of the graphite heat exchange block 5 to withstand pressure from both sides, thereby enabling the preload force of the spring 4 to be set larger, and ultimately enabling the maximum pressure that the O-type sealing ring between each graphite heat exchange block 5 can seal to be significantly increased, thereby improving the pressure bearing capacity of the condenser.

[0040] like Figure 1 As shown, in this embodiment, a baffle 10 is arranged between the graphite heat exchange block 5 and the outer cylinder 6. The number of the baffles 10 is the same as the number of the graphite heat exchange blocks 5. The baffles 10 are alternately arranged on the left or right side of each graphite heat exchange block 5 from top to bottom, so that the transverse through holes 14 in each graphite heat exchange block 5 are connected end to end to form a serpentine flow channel. The arrangement of the baffles 10 allows the refrigerant to pass through each graphite heat exchange block 5 in sequence from top to bottom, so that the refrigerant and the heat medium can exchange heat more fully.

[0041] like Figure 1 , 2 As shown, in this embodiment, the first sealing groove 16 is concentric with the outer diameter of the graphite heat exchange block 5. The advantage of the concentric structure is that the distribution of the transverse through holes 14 and the vertical through holes 15 on the graphite heat exchange block 5 can be more uniform and symmetrical, which is beneficial to reducing the stress in the graphite heat exchange block 5 after thermal expansion and contraction.

[0042] Second embodiment like Figure 6-8As shown, the difference between this embodiment and the first embodiment is that the first sealing groove 16 is not concentric with the outer diameter of the graphite heat exchange block 5 .

[0043] The eccentric design can make space on the outside of the first sealing groove 16, so that the heat medium outlet 12 can be set on the top of the upper head 2, and then the heat medium flows out of the heat medium channel 13 and directly flows upward to the heat medium outlet 12. Compared with the first embodiment in which the heat medium outlet 12 is set on the side of the upper head 2, the flow resistance of the heat medium can be significantly reduced.

Claims

1. A condenser for diazinon production, comprising a plurality of cylindrical graphite heat exchange blocks (5) and an outer cylinder (6) for accommodating the graphite heat exchange blocks (5), wherein the graphite heat exchange blocks (5) are arranged in sequence from top to bottom to form a group, and each graphite heat exchange block (5) is densely covered with transverse through holes (14) and vertical through holes (15), wherein the transverse through holes (14) serve as a refrigerant channel for the circulation of the refrigerant, and the vertical through holes (15) on each graphite heat exchange block (5) are connected end to end to serve as a heat medium channel (13) for the circulation of the heat medium, and the heat in the heat medium is transferred to the refrigerant through the graphite material to achieve heat exchange condensation, characterized in that: An annular region without vertical through holes (15) is provided on the upper end surface of the graphite heat exchange block (5), and vertical through holes (15) are provided on both the inner and outer sides of the annular region.

2. A condenser for diazinon production according to claim 1, characterized in that: On the upper end surface of the graphite heat exchange block (5), a first sealing groove (16) is machined in the annular region. The first sealing groove (16) is annular and has an O-ring disposed therein. The vertical through holes (15) are divided into two groups, inner and outer, by the first sealing groove (16). During operation, the heat medium first flows through a group of vertical through holes (15) on one side of the first sealing groove (16), then turns back and flows through a group of vertical through holes (15) on the other side of the first sealing groove (16).

3. A condenser for diazinon production according to claim 2, characterized in that: An upper end head (2) and a lower end head (7) also made of graphite material are respectively arranged at the upper and lower ends of the graphite heat exchange block group, and a heat medium inlet (3) and a heat medium outlet (12) are arranged on the upper end head (2); The upper and lower ends of the outer cylinder (6) are respectively connected to an upper cover (1) and a lower cover (8) corresponding to the upper end cover (2) and the lower end cover (7).

4. A condenser for diazinon production according to claim 3, characterized in that: The upper cover (1) is slidably mounted on the upper end of the outer cylinder (6), and under the elastic force of the spring (4), the upper head (2) is fitted onto the graphite heat exchange block (5) below it.

5. A condenser for diazinon production according to claim 2, characterized in that: A refrigerant inlet (11) and a refrigerant outlet (9) are provided on the side of the outer cylinder (6).

6. A condenser for diazinon production according to claim 2, characterized in that: A baffle (10) is arranged between the graphite heat exchange block (5) and the outer cylinder (6). The number of the baffles (10) is the same as the number of the graphite heat exchange blocks (5). The baffles (10) are arranged alternately on the left side or the right side of each graphite heat exchange block (5) from top to bottom, so that the transverse through holes (14) in each graphite heat exchange block (5) are connected end to end to form a serpentine flow channel.

7. A condenser for diazinon production according to any one of claims 1 to 6, characterized in that: The first sealing groove (16) is concentric with the outer diameter of the graphite heat exchange block (5).

8. A condenser for diazinon production according to any one of claims 1 to 6, characterized in that: The first sealing groove (16) is not concentric with the outer diameter of the graphite heat exchange block (5).

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