Energy-saving descaling water washing tower system

Abstract

The application relates to the field of MTO process equipment, in particular to an energy-saving descaling water washing tower system, which comprises a rewashing pipe connected to the bottom of a quenching tower to convey purified water of the quenching tower, filter tanks connected to the rewashing pipe, a buffer tank connected to the filter tanks, a water pump connected to the buffer tank, and a water washing tower connected to the water pump and used for washing reaction gas sent out by the quenching tower again, two filter tanks are arranged, three-way valves are arranged between the two filter tanks and the rewashing pipe and between the two filter tanks and the buffer tank, purified water of the quenching tower is used as washing water of the water washing tower, the amount of turbine water or condensate water is reduced, the total sewage discharge amount of the quenching tower and the water washing tower is reduced, and the treatment pressure is reduced.

Description

Technical Field

[0001] This application relates to the field of MTO process equipment, and in particular to an energy-saving descaling water washing tower system. Background Technology

[0002] In olefin plants, reaction gases rich in hydrocarbons and oxides are generated. In order to remove the oxides from the reaction gases, the reaction gases need to be passed through a quench tower and a water washing tower in sequence. In the quench tower and the water washing tower, the washing water and the reaction gases are in countercurrent contact so that the oxides in the reaction gases dissolve in the washing water to form purified water. The purified water is then sent back to the olefin plant for further reaction.

[0003] Existing water scrubbing towers use turbine condensate, boiler feedwater, or operation and maintenance condensate as the scrubbing water. For example, the water scrubbing tower and quench tower water supply system of a DMTO device is disclosed in announcement number CN217636962U.

[0004] Regarding the aforementioned technologies, using condensate as the washing water in the water scrubbing tower is wasteful and increases the total wastewater treatment capacity of the quench tower and the water scrubbing tower. Summary of the Invention

[0005] In order to improve the energy efficiency of the water washing tower and reduce the total wastewater treatment volume of the quench tower and the water washing tower, this application provides an energy-saving descaling water washing tower system.

[0006] The energy-saving descaling water washing tower system provided in this application adopts the following technical solution.

[0007] An energy-saving descaling water scrubbing tower system includes a rewash pipe connected to the bottom of a quench tower to deliver purified water to the quench tower, a filter tank connected to the rewash pipe, a buffer tank connected to the filter tank, a water pump connected to the buffer tank, and a water scrubbing tower connected to the water pump to rewash the reaction gas sent out from the quench tower. Two filter tanks are provided, and three-way valves are provided between the two filter tanks and the rewash pipe, as well as between the two filter tanks and the buffer tank.

[0008] By adopting the above technical solution, the purified water sent from the quench tower is filtered by the filter tank to remove catalyst solids and a small amount of oil from the purified water before being sent to the water washing tower for use. This reduces the use of condensate in the water washing tower, reduces the total amount of wastewater generated by the quench tower and the water washing tower, and also makes it less likely to cause blockage of the trays or coolers of the water washing tower.

[0009] Optionally, the filter tank includes a tank body with an upper section for connecting the rewash pipe and the buffer tank, a partition fixedly connected to the top of the tank body to divide the upper part of the tank body into two spaces, a filter screen located on the side of the partition body near the buffer tank for filtering the purified water fed into the buffer tank, and a slag discharge valve connected to the bottom of the tank body. The position of the tank body connecting to the rewash pipe is located on the side of the partition body away from the filter screen.

[0010] By adopting the above technical solution, oil sludge accumulates on the water surface on the side of the baffle away from the filter screen, allowing oil and water to separate smoothly and making it difficult for oil sludge to be discharged from the tank.

[0011] Optionally, the top of the tank is connected to an oil suction pipe with internal negative pressure. The oil suction pipe is connected to a flexible hose located inside the tank on the side of the partition away from the filter screen. The bottom end of the flexible hose is fixedly connected to a pipe end block. The tank is equipped with an oil suction cylinder with a power rod connected to the pipe end block.

[0012] By adopting the above technical solution, when a certain amount of oil accumulates, the bottom of the hose descends to suck away the oil.

[0013] Optionally, a peristaltic pump is connected between the rewash pipe and the tank, and the height at which the tank is connected to the buffer tank is higher than the height at which the tank is connected to the peristaltic pump.

[0014] By adopting the above technical solution, the purified water fed into the tank will not pass through the oil layer on the water surface, thereby reducing the possibility of secondary adsorption of oil by the catalyst particles in the purified water.

[0015] Optionally, two filters are provided, with a mesh plate fixedly connected to the two filters at positions close to each other. An upper sealing plate is rotatably connected to the upper part of the tank located on the mesh plate, and a lower sealing plate is rotatably connected to the lower part of the tank located on the mesh plate. The sides of the upper and lower sealing plates away from their respective rotation points are far apart. A flow-blocking plate is fixedly connected between the upper part of the filter and the mesh plate. The mesh plate has a through opening for purified water to pass through and is located above the position where the filter is connected to the mesh plate. The upper and lower sealing plates can seal the two far apart openings formed by the tank and the mesh plate.

[0016] By adopting the above technical solution, after a certain period of use, when a filter screen becomes clogged, the upper and lower sealing plates can be rotated, allowing another filter screen to filter catalyst particles in the water. At the same time, the clogged filter screen is backwashed, thereby extending the service life of the filter screen and reducing the time required for cleaning the filter screen.

[0017] Optionally, the bottoms of the two filters are close together, and the filters are arc-shaped.

[0018] By adopting the above technical solution, the opening area of ​​the plate is maximized, thereby increasing the water flow rate of the plate opening. The arc-shaped filter screen also results in a larger overall water flow rate of the filter screen.

[0019] Optionally, a row of baffle plates is fixedly connected to both opposite surfaces of the lower sealing plate. The baffle plates are inclined, and the side of the higher row of baffle plates away from the lower sealing plate is closer to the mesh plate.

[0020] By adopting the above technical solution, some of the impurities flushed down by the backwash filter can be blocked by the particle deflector, thereby reducing the amount of impurities sent out of the tank.

[0021] Optionally, the lower sealing plate is fixedly connected to two opposite sides with particle blocking plates. The particle blocking plates can abut against the side of the flow blocking plate away from the middle plate, and an overflow port is opened through the particle blocking plate near the lower sealing plate.

[0022] By adopting the above technical solution, as many catalyst particles as possible can be blocked by the particle-blocking plate.

[0023] Optionally, the particle blocking plate is located between two adjacent particle blocking plates, and the farthest distance between the flow port and the lower sealing plate is less than the farthest distance between the particle blocking plate and the lower sealing plate.

[0024] By adopting the above technical solution, some catalyst particles will be blocked by another baffle plate when they pass through the outlet with the water flow, further reducing the amount of catalyst particles in the purified water discharged from the tank.

[0025] Optionally, the particle blocking sheet includes several front pieces located on the side of the particle blocking plate closer to the middle plate and a rear piece located on the side of the particle blocking plate away from the middle plate, wherein the maximum distance between the rear piece and the lower sealing plate is greater than the maximum distance between the front piece and the lower sealing plate.

[0026] By adopting the above technical solution, the opening area of ​​the flow port can be maximized, ensuring the water flow rate while blocking as many impurity particles as possible.

[0027] In summary, this application includes at least the following beneficial effects.

[0028] The purified water from the quench tower is filtered through a filter tank to remove catalyst solids and a small amount of oil before being sent to the water washing tower for use. This reduces the amount of condensate used in the water washing tower, lowers the total amount of wastewater generated by the quench tower and water washing tower, and also reduces the likelihood of clogging of the trays or coolers in the water washing tower. Attached Figure Description

[0029] Figure 1 This is a simplified structural diagram of this application; Figure 2 This is a cross-sectional structural diagram of the tank. Figure 3 yes Figure 2 Enlarged view of point A in the middle.

[0030] Explanation of reference numerals in the attached diagram: 1. Rewash pipe; 2. Filter tank; 3. Buffer tank; 31. Rear plate; 32. Left chamber; 33. Right chamber; 34. Slag discharge valve; 4. Water pump; 41. Mesh plate; 42. Upper sealing plate; 43. Lower sealing plate; 44. Plate opening; 45. Baffle plate; 46. Particle baffle; 47. Particle baffle plate; 48. Flow port; 49. Front plate; 5. Water washing tower; 51. Three-way valve; 52. Tank body; 53. Baffle plate; 54. Filter screen; 55. Oil suction pipe; 56. Hose; 57. Pipe end block; 58. Oil suction cylinder; 59. Peristaltic pump. Detailed Implementation

[0031] The present application will be further described in detail below with reference to the accompanying drawings.

[0032] This application discloses an energy-saving descaling water washing tower system, referring to... Figure 1 The system includes a water scrubbing tower 5 that re-washes the reaction gas from the quench tower. A water pump 4 is connected to the cooler inlet of the water scrubbing tower 5, and a buffer tank 3 is connected to the inlet of the water pump 4 to reduce the pressure on the water pump 4 and improve its operational stability. A three-way valve 51 is connected to the inlet of the buffer tank 3. Both openings of the three-way valve 51 furthest from the buffer tank 3 are connected to filter tanks 2. The inlets of the two filter tanks 2 are connected to a three-way valve 51. The three-way valve 51 connected to the inlet of the filter tanks 2 is also connected to a peristaltic pump 59. The inlet of the peristaltic pump 59 is connected to a rewash pipe 1 for conveying purified water from the bottom of the quench tower. This ensures that the purified water produced by the quench tower is filtered before being supplied to the water scrubbing tower, reducing the total wastewater production. The two filter tanks 2 also ensure that the normal operation of the water scrubbing tower 5 is not easily affected if one filter tank 2 malfunctions or requires regular maintenance.

[0033] Reference Figure 1 and Figure 2The filter tank 2 includes a tank body 52 with two three-way valves 51 connected to each other on opposite sides at the top. A vertical baffle 53 is fixedly connected to the middle of the top of the tank body 52. ​​The baffle 53 is located between the position where the tank body 52 is connected to the peristaltic pump 59 and the position where the tank body 52 is connected to the buffer tank 3. There is a gap between the bottom of the baffle 53 and the bottom of the tank body 52 to allow purified water to pass through. At the same time, the position where the tank body 52 is connected to the peristaltic pump 59 is lower than the position where the tank body 52 is connected to the buffer tank 3, so that the height of the oil sludge accumulated on the water surface in the tank body 52 is higher than the height of the purified water entering the tank body 52. ​​This makes it difficult for the catalyst particles in the purified water to penetrate the oil layer on the water surface of the tank body 52, thereby reducing the possibility of secondary oil adsorption by the catalyst particles. The upper part of the tank 52 is detachably connected to an oil suction pipe 55, which is connected to an external oil pump to create a negative pressure inside the oil suction pipe 55. The oil suction pipe 55 is detachably connected to a hose 56 located inside the tank 52 via a threaded connector. The bottom end of the hose 56 is fixedly connected to a pipe end block 57. The top of the tank 52 is detachably connected to an oil suction cylinder 58, and the power rod of the oil suction cylinder 58 is detachably connected to the pipe end block 57. At the same time, a sight glass is provided on the side of the tank 52 that is connected to the peristaltic pump 59. When it is observed that the oil layer inside the tank has a certain thickness, the oil suction cylinder 58 is operated so that the bottom end of the hose 56 enters the oil layer for suction and discharge.

[0034] Reference Figure 2 Two filter screens 54 are detachably connected inside the tank body 52. ​​The filter screens 54 are located on the side of the partition 53 away from the hose 56. The filter screens 54 are arc-shaped, with their bottom ends close together. A vertical mesh plate 41 is detachably connected between the bottom ends of the two filter screens 54. The two filter screens 54 are symmetrically arranged with the mesh plate 41 as the center plane. A horizontal flow-blocking plate 45 is detachably connected between the upper part of the two filter screens 54 and the mesh plate 41. There is a gap between the side of the flow-blocking plate 45 away from the mesh plate 41 and the tank body 52 to allow purified water to pass through.

[0035] Reference Figure 2The mesh plate 41 is detachably connected to the inner wall of the tank body 52 to split the tank body 52 at the position where the mesh plate 41 is set into a left cavity 32 and a right cavity 33. The upper sealing plate 42 is rotatably connected to the upper part of the tank body 52 located above the mesh plate 41. The upper sealing plate 42 can block the upper opening of the left cavity 32 or the upper opening of the right cavity 33. The lower surface of the upper sealing plate 42 can abut against the upper surface of a flow baffle plate 45. A lower sealing plate 43 is rotatably connected to the tank body 52 below the mesh plate 41. The lower sealing plate 43 can seal the lower opening of either the left cavity 32 or the lower opening of the right cavity 33. A motor is installed outside the tank body 52 to drive the lower sealing plate 43 and the upper sealing plate 42 to rotate. The upper and lower openings of the left cavity 32 will not be blocked by the upper sealing plate 42 and the lower sealing plate 43 at the same time, nor will the upper and lower openings of the right cavity 33 be blocked by the upper sealing plate 42 and the lower sealing plate 43 at the same time. Meanwhile, the mesh plate 41 has a through-hole 44 for purified water to pass through. The lowest point of the through-hole 44 is higher than the height of the filter screen 54 connected to the mesh plate 41. A slag discharge valve 34 is fixedly connected to and connected to the bottom of the tank body 52 to periodically discharge the catalyst particles at the bottom of the tank body 52.

[0036] After a filter screen 54 becomes clogged after prolonged use, the upper sealing plate 42 and the lower sealing plate 43 are rotated so that another filter screen 54 filters the purified water, blocks the passage of catalyst particles, and allows the previously clogged filter screen 54 to be backwashed.

[0037] Reference Figure 2 and Figure 3 A row of baffle plates 46 is fixedly connected to both the upper and lower surfaces of the lower sealing plate 43. Each row of baffle plates 46 is inclined. The two rows of baffle plates 46 are symmetrically arranged with the lower sealing plate 43 as the center plane. The higher row of baffle plates 46 is further away from the lower sealing plate 43 and closer to the mesh plate 41, so that the catalyst particles can be blocked when they fall through the baffle plates 46. Each row of particle-blocking plates 46 includes several front plates 49 and one rear plate 31. The rear plate 31 is away from the mesh plate 41. The maximum distance between the rear plate 31 and the lower sealing plate 43 is greater than the maximum distance between the front plates 49 and the lower sealing plate 43. There is a particle-blocking plate 47 fixedly connected to the lower sealing plate 43 between each rear plate 31 and the adjacent front plate 49. When the lower sealing plate 43 is horizontal, the upper part of the particle-blocking plate 47 can abut against the flow-blocking plate 45. At the same time, the particle-blocking plate 47 is provided with a flow port 48. The maximum distance between the flow port 48 and the lower sealing plate 43 is less than the maximum distance between the rear plate 31 and the lower sealing plate 43.

[0038] Even if some catalyst particles washed down from the clogged filter screen 54 pass through the outlet 48, the catalyst particles will be carried by the water flow to the rear plate 31 for interception. Furthermore, after the lower sealing plate 43 rotates, the originally upward-facing baffle plate 46 will turn downwards, allowing the catalyst particles located between the baffle plate 46 and the lower sealing plate 43 to fall smoothly. There is a sufficiently large gap between the side of the baffle plate 47 facing away from the filter screen 54 and the inner wall of the tank 52, ensuring that the baffle plate 47 does not contact the inner wall of the tank 52 during rotation with the lower sealing plate 43.

[0039] The implementation principle of an energy-saving descaling water washing tower system according to an embodiment of this application is as follows: the purified water generated after the quench tower washes the reaction gas passes through the rewash pipe 1, peristaltic pump 59, filter tank 2 and buffer tank 3 in sequence, and is finally sent into the water washing tower 5 for use in washing the reaction gas, thereby reducing the amount of wastewater produced.

[0040] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. An energy-saving descaling water scrubbing tower system, characterized in that: The system includes a rewash pipe (1) connected to the bottom of the quench tower to deliver purified water to the quench tower, a filter tank (2) connected to the rewash pipe (1), a buffer tank (3) connected to the filter tank (2), a water pump (4) connected to the buffer tank (3), and a water scrubbing tower (5) connected to the water pump (4) to rewash the reaction gas sent from the quench tower. Two filter tanks (2) are provided, and three-way valves (51) are installed between the two filter tanks (2) and the rewash pipe (1), and between the two filter tanks (2) and the buffer tank (3). The filter tank (2) includes a tank body (52) at the top for communication between the rewash pipe (1) and the buffer tank (3), a partition (53) fixedly connected to the top of the tank body (52) to divide the upper part of the tank body (52) into two spaces, a filter screen (54) located on the side of the partition (53) near the tank body (52) connected to the buffer tank (3) to filter the purified water fed into the buffer tank (3), and a filter screen (54) connected to the bottom of the tank body (52). The slag discharge valve (34) and the tank body (52) are connected to the rewash pipe (1) on the side of the partition plate (53) away from the filter screen (54); two filter screens (54) are provided, and a mesh plate (41) is fixedly connected to the two filter screens (54) at the position close to each other. The upper sealing plate (42) is rotatably connected to the upper part of the tank body (52) above the mesh plate (41), and the lower sealing plate (43) is rotatably connected to the lower part of the tank body (52) below the mesh plate (41). (42) and the lower sealing plate (43) are far apart from their respective rotation points. A flow-blocking plate (45) is fixedly connected between the upper part of the filter screen (54) and the middle plate (41). The middle plate (41) has a through opening (44) for purified water to pass through and is located above the position where the filter screen (54) is connected to the middle plate (41). The upper sealing plate (42) and the lower sealing plate (43) can seal the two far apart openings formed by the tank (52) and the middle plate (41).

2. The energy-saving descaling water washing tower system according to claim 1, characterized in that: The top of the tank (52) is connected to an oil suction pipe (55) with negative pressure inside. The oil suction pipe (55) is connected to a hose (56) located on the side of the tank (52) away from the filter screen (54) of the partition (53). The bottom end of the hose (56) is fixedly connected to a pipe end block (57). The tank (52) is provided with an oil suction cylinder (58) with a power rod connected to the pipe end block (57).

3. The energy-saving descaling water washing tower system according to claim 2, characterized in that: A peristaltic pump (59) is connected between the rewash pipe (1) and the tank (52). The height of the tank (52) connected to the buffer tank (3) is higher than the height of the tank (52) connected to the peristaltic pump (59).

4. The energy-saving descaling water washing tower system according to claim 1, characterized in that: The bottoms of the two filters (54) are close together, and the filters (54) are arc-shaped.

5. The energy-saving descaling water washing tower system according to claim 1, characterized in that: A row of baffle plates (46) is fixedly connected to both opposite surfaces of the lower sealing plate (43). The baffle plates (46) are inclined, and the side of the higher row of baffle plates (46) away from the lower sealing plate (43) is close to the mesh plate (41).

6. The energy-saving descaling water washing tower system according to claim 5, characterized in that: The lower sealing plate (43) is fixedly connected to two opposing sides with particle blocking plates (47). The particle blocking plates (47) can abut against the side of the flow blocking plate (45) away from the net plate (41). The particle blocking plates (47) have a through-flow port (48) on the side of the lower sealing plate (43).

7. The energy-saving descaling water washing tower system according to claim 6, characterized in that: The particle blocking plate (47) is located between two adjacent particle blocking plates (46), and the farthest distance between the flow port (48) and the lower sealing plate (43) is less than the farthest distance between the particle blocking plate (46) and the lower sealing plate (43).

8. The energy-saving descaling water washing tower system according to claim 7, characterized in that: The particle blocking plate (46) includes several front pieces (49) located on the side of the particle blocking plate (47) close to the middle plate (41) and a rear piece (31) located on the side of the particle blocking plate (47) away from the middle plate (41). The maximum distance between the rear piece (31) and the lower sealing plate (43) is greater than the maximum distance between the front piece (49) and the lower sealing plate (43).

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