Automatic flushing device for alkaline washing tower of VCM (Vinyl Chloride Monomer) device

Abstract

The utility model relates to the technical field of chemical production, in particular to an automatic flushing device for an alkaline tower of a VCM (Vinyl Chloride Monomer) device, and aims to solve the problems that in the long-time operation process of the conventional alkaline tower, sodium carbonate and other salt inorganic matters are generated inside the alkaline tower, crystals are extremely easy to form inside the alkaline tower and inside a pipeline, the purification capacity of the alkaline tower is reduced, and the production cost is reduced. Meanwhile, time and labor are wasted in alkali liquor concentration detection and washing of the alkaline washing tower. According to the device, an on-line alkali liquor and sodium carbonate concentration monitor, an alkali preparation tank switch valve, an alkali preparation tank, an alkali circulating pump, a new water pipe switch valve, an alkali circulating tank outlet pipe switch valve and other parts are added in the operation of an existing VCM device alkali washing tower, so that the concentration detection and flushing process in the alkali washing tower replaces manual field sampling analysis; the labor intensity of operators is effectively reduced, so that the automatic control flushing of the alkaline washing tower is ensured, and the overall operation efficiency of the alkaline washing tower is greatly improved.

Description

Technical Field

[0001] The utility model relates to the technical field of chemical production, in particular to an automatic flushing device for an alkali washing tower of a VCM device. Background Art

[0002] Currently, in the PVC chemical production process, the VCM unit's caustic wash tower utilizes alkali to transfer mass and heat within the crude vinyl chloride gas, absorbing residual carbon dioxide and hydrogen chloride in the gas to produce slightly alkaline, purified crude vinyl chloride gas. This effectively prevents acid corrosion in the VCM unit's equipment and pipelines. However, over long periods of operation, the alkali concentration in the caustic wash tower gradually decreases. Furthermore, due to the absorption of hydrogen chloride and carbon dioxide, it reacts with sodium hydroxide to form inorganic salts such as sodium carbonate. Over time, these salts crystallize within the tower and pipelines, potentially reducing the tower's purification capacity. Therefore, real-time monitoring of the alkali concentration in the caustic wash tower and its self-flushing significantly impact its overall operational efficiency. Utility Model Content

[0003] The utility model provides an automatic flushing device for an alkali washing tower of a VCM device, so as to solve the problems existing in the above background.

[0004] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0005] The invention discloses an automatic flushing device for an alkali washing tower of a VCM device, comprising an alkali washing tower, wherein the inlet of the alkali washing tower is connected to an alkali circulation tank, the outlet of the alkali circulation tank is connected to an alkali preparation tank, the inlet of the alkali circulation tank is connected to the outlet of the alkali washing tower, the bottom side of the alkali circulation tank is further connected to a wastewater delivery pump, and the top side of the alkali circulation tank is further connected to a new water pipeline.

[0006] Furthermore, a concentration monitor, an alkali circulation tank outlet pipe switch valve and an alkali circulation pump are sequentially provided on the pipeline between the outlet of the alkali circulation tank and the inlet of the alkali washing tower, and the outlet of the alkali circulation pump is connected to the alkali solution inlet of the alkali washing tower.

[0007] Furthermore, a wastewater pump inlet switch valve and a wastewater pump outlet switch valve are provided on the bottom outlet pipe of the alkali circulation tank, and the wastewater pump is arranged between the wastewater pump inlet switch valve and the wastewater pump outlet switch valve.

[0008] Furthermore, the inlet of the alkali preparation tank is connected to an alkali solution pipeline, and an alkali preparation tank switch valve is provided on the pipeline between the outlet of the alkali preparation tank and the inlet of the alkali circulation pump.

[0009] Furthermore, the top of the alkali washing tower is connected to a gas cabinet and a compression device respectively.

[0010] Furthermore, a new water pipe switch valve is provided on the new water pipe line.

[0011] The utility model has the following beneficial effects:

[0012] The utility model provides an automatic flushing device for the alkali washing tower of a VCM device. By adding components such as an online alkali solution, a sodium carbonate concentration monitor, an alkali preparation tank switch valve, an alkali preparation tank, an alkali circulation pump, a new water pipe switch valve, and an alkali circulation tank outlet pipe switch valve to the operation of the existing VCM device alkali washing tower, the concentration detection and flushing process inside the alkali washing tower replaces manual on-site sampling and analysis, effectively reducing the labor intensity of operators, thereby ensuring the automatic control flushing of the alkali washing tower and greatly improving the overall operating efficiency of the alkali washing tower. The utility model solves the problem that during the long-term operation of the alkali washing tower, due to the internal generation of sodium carbonate and other salt inorganic substances, it is very easy to form crystals inside the alkali washing tower and in the pipeline, resulting in a decrease in the purification capacity of the alkali washing tower, and at the same time making the alkali solution concentration detection and alkali washing tower flushing more time-consuming and labor-intensive. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of the overall structure of the utility model.

[0014] The meanings of the reference numerals are as follows:

[0015] 1. Alkali preparation tank switch valve; 2. Alkali preparation tank; 3. Wastewater transfer pump inlet switch valve; 4. Wastewater transfer pump; 5. Wastewater transfer pump outlet switch valve; 6. Alkali washing tower; 7. Alkali circulation tank; 8. New water pipe switch valve; 9. Concentration monitor; 10. Alkali circulation tank outlet pipe switch valve; 11. Alkali circulation pump; 12. Alkali solution inlet of alkali washing tower; 13. New water pipeline; 14. Gas cabinet; 15. Compression device; 16. Crude vinyl chloride; 17. Alkali solution pipeline. DETAILED DESCRIPTION

[0016] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0017] like Figure 1 As shown, an automatic flushing device for an alkali washing tower of a VCM device includes an alkali washing tower 6, the inlet of the alkali washing tower 6 is connected to an alkali circulation tank 7, the outlet of the alkali circulation tank 7 is connected to an alkali preparation tank 2, the inlet of the alkali circulation tank 7 is connected to the outlet of the alkali washing tower 6, the bottom side of the alkali circulation tank 7 is also connected to a wastewater delivery pump 4, and the top side of the alkali circulation tank 7 is also connected to a new water pipeline 13.

[0018] The pipeline between the outlet of the alkali circulation tank 7 and the inlet of the alkali washing tower 6 is provided with a concentration monitor 9, an alkali circulation tank outlet pipe switch valve 10 and an alkali circulation pump 11 in sequence, and the outlet of the alkali circulation pump 11 is connected to the alkali solution inlet 12 of the alkali washing tower.

[0019] A wastewater pump inlet switch valve 3 and a wastewater pump outlet switch valve 5 are provided on the bottom outlet pipe of the alkali circulation tank 7, and the wastewater pump 4 is arranged between the wastewater pump inlet switch valve 3 and the wastewater pump outlet switch valve 5.

[0020] The inlet of the alkali preparation tank 2 is connected to the alkali solution pipeline 17 , and the alkali preparation tank switch valve 1 is provided on the pipeline between the outlet of the alkali preparation tank 2 and the inlet of the alkali circulation pump 11 .

[0021] The top of the alkali washing tower 6 is connected to a gas cabinet 14 and a compression device 15 respectively.

[0022] A new water pipe on-off valve 8 is provided on the new water pipe line 13 .

[0023] During specific application of the present invention, when the alkali washing tower 6 is in normal operation, the alkali configuration tank switch valve 1, the wastewater delivery pump inlet switch valve 3 and the new water pipe switch valve 8 are controlled to be closed, the alkali circulation tank outlet pipe switch valve 10 is opened, the alkali circulation pump 11 operates normally, and the alkali solution is circulated and delivered to the inside of the alkali washing tower 6 for normal purification. During the automatic tower washing process, when the concentration monitor 9 of alkali concentration and sodium carbonate concentration detects that the alkali concentration in the alkali solution delivered from the alkali circulation tank 7 is lower than the range of 9%-14% and the sodium carbonate concentration is higher than the index of 5%-8%, the system starts to stop the alkali circulation and starts automatic tower washing; when the alkali circulation tank 7 is emptied and replaced, the alkali circulation pump 11 stops running, the alkali circulation tank outlet pipe switch valve 10 is closed, and the wastewater delivery pump 4 starts to start. After the start signal is transmitted to the wastewater delivery pump inlet switch valve 3, the valve is opened and the opening success signal is transmitted to the wastewater delivery pump outlet switch valve 5. The wastewater delivery pump outlet switch valve 5 opens after a delay of 3s and starts to discharge the waste alkali solution inside the alkali circulation tank 7 to the wastewater treatment device; when the liquid level is lower than 10%, the new water pipe switch valve 8 is opened to add new water and flush the residue inside the alkali circulation tank 7. After flushing for 5 minutes, the wastewater delivery pump inlet switch valve 3, wastewater delivery pump 4 and wastewater delivery pump outlet switch valve 5 are closed. Furthermore, when the liquid level of the alkali circulation tank 7 reaches 30%, the alkali circulation tank outlet pipe switch valve 10 and the alkali circulation pump 11 are opened to begin flushing the alkali washing tower 6. When the liquid level of the alkali circulation tank 7 reaches 70%, the new water pipe switch valve 8 is closed, and the alkali washing tower 6 is circulated and flushed for 15 minutes. Then, the alkali circulation tank 7 is emptied and replaced once again. After the final cleaning is completed, the alkali solution is reconfigured and the purification of the alkali washing tower 6 begins. The alkali configuration tank switch valve 1 is first opened, and after 2 seconds, the new water pipe switch valve 8 is closed to start the alkali solution circulation. At the same time, 32% of the alkali solution is transferred from the alkali configuration tank 2 to the alkali circulation tank 7. When the liquid level of the alkali circulation tank 7 reaches 70%, the alkali circulation tank outlet pipe switch valve 10 is opened and the alkali configuration tank switch valve 1 is closed, thereby completing the automatic flushing of the alkali washing tower 6. The entire process effectively reduces the labor intensity of the operators, thereby ensuring the automatic control flushing of the alkali washing tower 6 and greatly improving the overall operating efficiency of the alkali washing tower 6. Therefore, the device has good practicality.

Claims

1. An automatic flushing device for an alkali washing tower of a VCM device, comprising an alkali washing tower (6), characterized in that: The inlet of the alkali washing tower (6) is connected to an alkali circulation tank (7), the outlet of the alkali circulation tank (7) is connected to the alkali preparation tank (2), the inlet of the alkali circulation tank (7) is connected to the outlet of the alkali washing tower (6), the bottom side of the alkali circulation tank (7) is also connected to a wastewater delivery pump (4), and the top side of the alkali circulation tank (7) is also connected to a new water pipeline (13).

2. The automatic flushing device for the alkali washing tower of a VCM device according to claim 1, characterized in that: A concentration monitor (9), an alkali circulation tank outlet pipe switch valve (10) and an alkali circulation pump (11) are sequentially provided on the pipeline between the outlet of the alkali circulation tank (7) and the inlet of the alkali washing tower (6), and the outlet of the alkali circulation pump (11) is connected to the alkali solution inlet (12) of the alkali washing tower.

3. The automatic flushing device for the alkali washing tower of a VCM device according to claim 2, characterized in that: A wastewater delivery pump inlet switch valve (3) and a wastewater delivery pump outlet switch valve (5) are provided on the bottom outlet pipe of the alkali circulation tank (7), and the wastewater delivery pump (4) is arranged between the wastewater delivery pump inlet switch valve (3) and the wastewater delivery pump outlet switch valve (5).

4. The automatic flushing device for the alkali washing tower of a VCM device according to claim 1, characterized in that: The inlet of the alkali preparation tank (2) is connected to an alkali solution pipeline (17), and an alkali preparation tank switch valve (1) is provided on the pipeline between the outlet of the alkali preparation tank (2) and the inlet of the alkali circulation pump (11).

5. The automatic flushing device for the alkali washing tower of a VCM device according to claim 2, characterized in that: The top of the alkali washing tower (6) is connected to a gas cabinet (14) and a compression device (15) respectively.

6. The automatic flushing device for the alkali washing tower of a VCM device according to claim 1, characterized in that: The new water pipeline (13) is provided with a new water pipe on-off valve (8).

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