A condenser for diazinon production

Abstract

A condenser for diazinon production relates to the field of chemical condensing equipment and includes 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 arranged in a group from top to bottom. Each graphite heat exchange block is densely covered with transverse through-holes and vertical through-holes. The transverse through-holes serve as refrigerant channels for the circulation of refrigerant. The vertical through-holes on each graphite heat exchange block are connected end to end to serve as heat medium channels for the circulation of heat medium. Heat in the heat medium is transferred to the refrigerant through the graphite material. A first sealing groove is machined on the 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, an inner and an outer group, by the first sealing groove. By dividing the heat medium channel into two groups, the present invention achieves a return flow of the heat medium within 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.

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 required in the production process of diazinon. It has strong corrosion resistance and good thermal conductivity, which can meet the heat exchange requirements in the production process of diazinon.

[0003] A traditional block-hole graphite condenser (heat exchanger) consists of several cylindrical graphite heat exchange blocks, each of which is covered with horizontal and vertical through-holes, which are interlaced. When the blocks are stacked into a cylinder, the vertical through-holes on each block are connected in series to form a set of long through-holes that run vertically from top to bottom. These serve as channels for the corrosive medium being condensed, called heat medium channels. The heat medium channels are connected to the top and bottom ends of the block-hole graphite condenser. An annular space is left between the outside of each graphite heat exchange block and the outer wall of the block-hole graphite condenser (heat exchanger). This annular space, connected to the horizontal through-holes on each block, 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 refrigerant channel, respectively. Heat is transferred through the graphite material, achieving heat exchange and condensation.

[0004] The existing block hole graphite condenser (heat exchanger) has the following technical problems:

[0005] The graphite heat exchange block is cut into a three-dimensional grid structure by horizontal and vertical through holes everywhere, which makes its structural strength poor. At the same time, graphite is a brittle material. 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.

[0006] For a long time, technicians have tried to develop high-performance polymer materials 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

[0007] The present invention provides a condenser for diazinon production. By improving the existing block-hole graphite condenser, in particular optimizing the design of the graphite heat exchange blocks inside the condenser, the structural strength of the graphite heat exchange blocks is enhanced, while the heat exchange efficiency of the block-hole graphite condenser is improved and the condensation speed is increased.

[0008] 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. The graphite heat exchange blocks are sequentially arranged in a group from top to bottom. Each graphite heat exchange block is densely covered with transverse through holes and vertical through holes. The transverse through holes serve as refrigerant channels for the circulation of refrigerant. The vertical through holes on each graphite heat exchange block are connected end to end to serve as heat medium channels for the circulation of heat medium. The heat in the heat medium is transferred to the refrigerant through the graphite material, thereby achieving heat exchange and condensation.

[0009] An annular area without vertical through holes is provided on the upper end surface of the graphite heat exchange block, and vertical through holes are provided on both inner and outer sides of the annular area.

[0010] As a preferred solution, a first sealing groove is processed in the annular area on the upper end surface of the graphite heat exchange block. The first sealing groove is annular and an O-ring is arranged inside it. 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.

[0011] 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;

[0012] 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.

[0013] As a preferred solution, the upper cover is slidably mounted on the upper end of the outer cylinder, and the upper head is affixed to the graphite heat exchange block below it under the elastic force of the spring.

[0014] As a preferred solution, a refrigerant inlet and a refrigerant outlet are provided on the side of the outer cylinder.

[0015] As a preferred solution, a baffle is provided 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. 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.

[0016] As a preferred solution, the first sealing groove is concentric with the outer diameter of the graphite heat exchange block.

[0017] As a preferred solution, the first sealing groove is not concentric with the outer diameter of the graphite heat exchange block.

[0018] The beneficial effects of the present invention are:

[0019] 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. Its skeleton support function is more capable of withstanding the pressure from the upper and lower sides of the graphite heat exchange block, thereby making the graphite heat exchange block less likely to be damaged by pressure.

[0020] Furthermore, to accommodate the thermal expansion and contraction of the graphite heat exchange blocks, the upper head in the present invention is installed in a floating manner. With this installation method, the maximum pressure that the O-rings between the graphite heat exchange blocks can seal depends on the preload of the springs, and the upper limit of the spring preload depends on the graphite heat exchange blocks' ability to withstand pressure from both sides. In the present invention, the provision of an annular area without vertical through-holes significantly improves the graphite heat exchange blocks' ability to withstand pressure from both sides, thereby enabling a greater preload of the spring. Ultimately, this significantly increases the maximum pressure that the O-rings between the graphite heat exchange blocks can seal, thereby improving the condenser's pressure-bearing capacity.

[0021] 2. The annular area is a unique structure in the present invention. On the basis of this unique structure, the present invention provides 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.

[0022] 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. This 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

[0023] Figure 1 It is a schematic diagram of the overall structure of the first embodiment of the present invention.

[0024] Figure 2 yes Figure 1 Schematic diagram of the structure of the top of the graphite heat exchange block.

[0025] Figure 3 yes Figure 2 Left view of .

[0026] Figure 4 yes Figure 3 Cross-sectional view at the middle BB.

[0027] Figure 5 yes Figure 2 Cross-sectional view at AA in the middle.

[0028] Figure 6 It is a schematic diagram of the overall structure of the second embodiment of the present invention.

[0029] Figure 7 yes Figure 6 Schematic diagram of the structure of the top of the graphite heat exchange block.

[0030] Figure 8 yes Figure 7 Cross-sectional view at CC.

[0031] Figure 9 This is a schematic diagram of the distribution of vertical through holes on the top of a graphite heat exchange block in the prior art.

[0032] Figure 10 yes Figure 9 Left view of .

[0033] 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

[0034] The present invention will be further described below with reference to the accompanying drawings.

[0035] First embodiment

[0036] like Figure 1-10 As shown, this embodiment includes several 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 to form 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, achieving heat exchange and condensation. The above is a conventional structure in the prior art and will not be repeated here.

[0037] 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. Vertical through-holes 15 are provided on both the inner and outer sides of the annular region. The absence of vertical through-holes 15 within the annular region significantly enhances the structural strength of the entity within this region compared to other regions. The stronger annular region acts as a skeleton within the graphite heat exchange block 5, providing support that is more capable of withstanding pressure from both the upper and lower sides of the graphite heat exchange block 5, thereby preventing the block 5 from being damaged by pressure.

[0038] 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 therein. The vertical through hole 15 is divided into two groups, an inner group and an outer group, by the annular first sealing groove 16 and isolated and sealed by the O-ring.

[0039] In this embodiment, a second sealing groove 17 is provided on 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.

[0040] like Figure 2 As shown, in this embodiment, the upper and lower ends of the graphite heat exchange blocks 5 are respectively provided with an upper head 2 and a lower head 7, also made of graphite. 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 the graphite heat exchange blocks 5 form a continuous heat medium flow path made entirely of graphite (impregnated graphite). The corrosive heat medium is confined within the space enclosed by the graphite material, thereby preventing corrosion damage to the condenser.

[0041] 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.

[0042] 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 .

[0043] Working principle:

[0044] During operation, refrigerant flows in through the refrigerant inlet 11, 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 through the refrigerant outlet 9. Simultaneously, heat medium flows in through the heat medium inlet 3, first flows through a set of vertical through-holes 15 on the inner side of the first sealing groove 16, then turns back inside the lower head 7, and then flows through a set of vertical through-holes 15 on the outer side of the first sealing groove 16, and finally flows out through the heat medium outlet 12. By dividing the heat medium channel 13 into two groups, the heat medium achieves a return flow within the heat medium channel 13. This return flow increases the flow rate of the heat medium and the convective heat transfer coefficient, thereby effectively improving the heat exchange efficiency and increasing the condensation speed.

[0045] 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 elastic force of the spring 4 forces the upper head 2 to fit over the graphite heat exchange block 5 below it. This design allows the upper head 2 and upper cover 1 to elastically slide with the thermal expansion and contraction of the graphite heat exchange block 5, thereby preventing the graphite heat exchange block 5, upper head 2, and lower head 7 from being crushed. Furthermore, when the upper head 2 is installed in this manner, the maximum pressure at which the O-rings between the graphite heat exchange blocks 5 can seal depends on the preload force of the spring 4, and the upper limit of the spring 4 preload force depends on the graphite heat exchange block 5's ability to withstand pressure from both above and below. In the present invention, the provision of an annular area without vertical through-holes 15 significantly improves the graphite heat exchange block 5's ability to withstand pressure from both above and below, thereby allowing for a greater preload force on the spring 4. Ultimately, this significantly increases the maximum pressure at which the O-rings between the graphite heat exchange blocks 5 can seal, thereby improving the condenser's pressure-bearing capacity.

[0046] like Figure 1 As shown, in this embodiment, baffles 10 are disposed between the graphite heat exchange blocks 5 and the outer cylinder 6. The number of baffles 10 is the same as the number of graphite heat exchange blocks 5. Each baffle 10 is alternately positioned on the left or right side of each graphite heat exchange block 5 from top to bottom, thereby connecting the transverse through holes 14 in each graphite heat exchange block 5 end to end to form a serpentine flow channel. The placement of the baffles 10 allows the refrigerant to pass through each graphite heat exchange block 5 sequentially from top to bottom, thereby ensuring more efficient heat exchange between the refrigerant and the heat medium.

[0047] 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.

[0048] Second embodiment

[0049] like Figure 6-8 As 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 .

[0050] The non-concentric design can make space on the outside of the first sealing groove 16, so that the heat medium outlet 12 can be set at the top of the upper head 2, and then the heat medium flows out of the heat medium channel 13 and flows directly 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 sequentially arranged in a group from top to bottom, 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 refrigerant channels for the circulation of refrigerant, and the vertical through holes (15) on each graphite heat exchange block (5) are connected end to end to serve as heat medium channels (13) for the circulation of heat medium, wherein the heat in the heat medium is transferred to the refrigerant through the graphite material, thereby achieving heat exchange condensation, and wherein: The upper end surface of the graphite heat exchange block (5) is provided with an annular region without vertical through holes (15), and vertical through holes (15) are provided on both the inner and outer sides of the annular region; 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 therein. The vertical through holes (15) are divided into two groups, an inner group and an outer group, 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), and then flows back through a group of vertical through holes (15) on the other side of the first sealing groove (16). When viewed from the end face of the graphite heat exchange block (5), the vertical through holes (15) are arranged in groups, and a solid space is left between two adjacent groups of vertical through holes (15). The transverse through holes (14) are arranged in the solid space between the two adjacent groups of vertical through holes (15), thereby ensuring that the transverse through holes and the vertical through holes are not connected; A circular ring-shaped area without vertical through holes (15) is provided in the array of vertical through holes (15) on the graphite heat exchange block (5). Since there are no vertical through holes (15) in this area, the structural strength of the entity in this area is significantly enhanced compared with other areas. The circular ring-shaped area with higher strength is equivalent to the skeleton in the graphite heat exchange block (5). The skeleton support function is more capable of withstanding the pressure from the upper and lower sides of the graphite heat exchange block (5), thereby making the graphite heat exchange block (5) less likely to be damaged by pressure.

2. A condenser for diazinon production according to claim 1, characterized in that: The upper and lower ends of the graphite heat exchange block group are respectively provided with an upper head (2) and a lower head (7) 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 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 head (2) and the lower head (7).

3. A condenser for diazinon production according to claim 2, 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.

4. The condenser for diazinon production according to claim 1, characterized in that: A refrigerant inlet (11) and a refrigerant outlet (9) are provided on the side of the outer cylinder (6).

5. The condenser for diazinon production according to claim 1, characterized in that: A baffle (10) is provided 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 provided 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.

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

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

Images