A device for methanol to olefins plant oxide stripper plugging disposal

Abstract

The utility model discloses a kind of methanol to olefin device oxide stripping column jam disposal device, including oxide stripping column, the reflux pump of the top of oxide stripping column is equipped with top reflux line, from the reflux pump connection to oxide stripping column;Bottom liquid phase delivery pump is equipped with bottom reflux line, from the delivery pump connection to oxide stripping column;Setting connecting pipeline, from delivery pump inlet connection to reflux pump inlet;It further includes cleaning agent storage tank and diaphragm metering pump, the cleaning agent storage tank bottom outlet is connected to the oxide stripping column liquid phase outlet via diaphragm metering pump.The device of the utility model injects cleaning solution into oxide stripping column by cleaning agent storage tank, using soaking, circulation etc. mode washing, can effectively solve the problem of oxide stripping column tray blockage, ensure that equipment long-period stable operation.

Description

Technical Field

[0001] This utility model belongs to the field of methanol-to-olefins (MTO) technology, specifically relating to a device for dealing with blockage in the oxide stripping tower of a methanol-to-olefins plant. Background Technology

[0002] HYDRO / UOP's MTO process is one of the world's leading methods for methanol-to-olefins (MTO). During the methanol-to-olefins reaction, various oxygen-containing byproducts are generated. To increase the yield of low-carbon olefins, the process water from the MTO washing tower and separation tower, as well as the condensate from the first stage of the product gas compressor, which contains small amounts of oxygen-containing compounds (such as methanol, dimethyl ether, aldehydes, and ketones), is sent to an oxide stripping tower for stripping to recover these organic compounds. The recovered organic compounds are then returned to the MTO reactor to participate in the reaction again. This oxygen-containing wastewater contains catalyst powder and oily substances. During long-term operation, deposits easily accumulate on the trays of the oxide stripping tower. Severe agglomeration increases the pressure differential on the trays, forming a liquid seal and affecting the operating efficiency of the oxide stripping tower, becoming a common problem in the MTO industry.

[0003] In actual production, the problem of clogging on the trays of oxide stripping towers is usually addressed manually during unit maintenance. The trays and bottom of the tower are cleaned manually, but due to the small diameter of the upper trays and the small spacing between them, manual cleaning is difficult and time-consuming, failing to completely solve the clogging problem. Some similar units have considered injecting a certain proportion of solvent into the oxide stripping tower during production to dissolve and clean the scale on the trays. The main drawback of this approach is the need to continuously inject solvent based on the total wastewater discharge from the oxide stripping tower to maintain the solvent concentration and thus the cleaning effect, resulting in high solvent consumption costs. Furthermore, the cleaning effect and the impact of the solvent on downstream wastewater treatment require further verification and experimentation.

[0004] Therefore, production practices require the exploration of a new, effective, and efficient method for dealing with blockages in the oxide stripping tower of a methanol-to-olefins unit. Summary of the Invention

[0005] The purpose of this invention is to provide a device for treating blockage in the oxide stripping tower of a methanol-to-olefins (MTO) plant. This device utilizes a chemical cleaning solution injected into the oxide stripping tower for soaking and circulation, thereby cleaning the tower. The device effectively solves the problem of tray blockage in the oxide stripping tower of an MTO plant. The cleaned trays are essentially brand new, ensuring long-term stable operation of the equipment. Furthermore, the device significantly reduces maintenance difficulty and cycle time compared to manual methods, resulting in lower overall construction costs and improved efficiency in resolving oxide stripping tower blockage issues, thus further enhancing overall economic benefits.

[0006] To achieve the above-mentioned objectives, the present invention adopts the following technical solution: An apparatus for treating blockage in an oxide stripping tower of a methanol-to-olefins plant, comprising an oxide stripping tower, characterized in that the apparatus further comprises: A top reflux tank is provided, wherein the top vapor outlet of the oxide stripping tower is connected to the top reflux tank via a cooler; A reflux pump is provided, with the liquid phase outlet at the bottom of the top reflux tank connected to the reflux pump, which is connected to the tank area. A top reflux line is connected from the reflux pump (4) to the oxide stripping tower; A transfer pump is connected to the liquid phase outlet at the bottom of the oxide stripping tower, and the transfer pump is connected to the downstream oxide absorption tower; A bottom reflux line is connected from the outlet of the transfer pump to the oxide stripping tower; A cleaning agent storage tank and a diaphragm metering pump, wherein the bottom outlet of the cleaning agent storage tank is connected to the diaphragm metering pump, and the diaphragm metering pump is connected to the liquid phase outlet of the oxide stripping tower; A connecting line connects the inlet of the delivery pump and the inlet of the return pump.

[0007] Furthermore, a filter is provided on the connecting pipeline.

[0008] Furthermore, a second flow control valve is installed on the return line at the top of the tower to control the return flow.

[0009] Furthermore, a first flow control valve is installed on the return line at the bottom of the tower to control the return flow.

[0010] Furthermore, a level gauge is provided in the cleaning agent storage tank to control the liquid level.

[0011] Furthermore, the top gas phase outlet of the reflux tank is connected to the reactor.

[0012] Beneficial Effects: This utility model discloses a device for treating blockage in the oxide stripping tower of a methanol-to-olefins (MTO) unit. It utilizes a chemical washing solution injected into the oxide stripping tower, employing methods such as soaking and circulation for washing, followed by filtration and collection of the waste liquid. This device effectively solves the problem of tray blockage in the oxide stripping tower of an MTO unit. The cleaned trays are essentially refilled, ensuring long-term stable operation of the equipment. Furthermore, it significantly reduces the difficulty and cycle of maintenance compared to manual methods, resulting in lower overall construction costs and improved efficiency in resolving oxide stripping tower blockage issues, thus further enhancing overall economic benefits. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the structure of a blockage treatment device for an oxide stripping tower in a methanol-to-olefins plant according to the present invention. In the diagram: 1-Oxide stripping tower; 2-Cooler; 3-Top reflux tank; 4-Reflux pump; 5-Transfer pump; 6-Filter; 7-Level gauge; 8-Diaphragm metering pump; 9-Cleaning agent storage tank; 10-Connecting pipeline; 11-Top reflux line; 12-Bottom reflux line; 13-First flow control valve; 14-Second flow control valve. Detailed Implementation

[0014] The specific embodiments of the present invention will be described in detail below. However, it should be noted that the scope of protection of the present invention is not limited by these specific embodiments, but is determined by the claims.

[0015] like Figure 1 As shown, the present invention provides a device for handling blockage in the oxide stripping tower of a methanol-to-olefins plant, which can be modified based on the original oxide stripping tower 1.

[0016] In the MTO unit, oxide stripping tower 1 is used for stripping oxygenated wastewater to recover organic compounds such as methanol, dimethyl ether, aldehydes, and ketones. Oxygenated water enters oxide stripping tower 1 from the top. The top gaseous material is cooled by cooler 2 and then enters top reflux tank 3. The top gaseous material in top reflux tank 3 returns to the reactor, while the bottom liquid material is sent to the tank area via reflux pump 4. After stripping, the bottom liquid material in oxide stripping tower 1 is sent to the downstream oxide absorption tower for absorption via transfer pump 5. Oxygenated wastewater from the oxide absorption tower enters oxide stripping tower 1 from the bottom.

[0017] A top reflux line 11 is provided at the outlet of the reflux pump 4, connected to the upper feed inlet of the oxide stripping tower 1. A second flow control valve 14 is provided on the top reflux line 11 to control the top reflux flow rate. A bottom reflux line 12 is provided at the outlet of the transfer pump 5, connected to the lower feed inlet of the oxide stripping tower 1. A first flow control valve 13 is provided on the bottom reflux line 12 to control the top reflux flow rate. A connecting pipeline 10 is provided, with the inlet of the transfer pump 5 connected to the connecting pipeline 10, and the connecting pipeline 10 connected to the inlet of the reflux pump 4. Further, a filter 6 is provided on the connecting pipeline 10. The device also includes a cleaning agent storage tank 9 and a diaphragm metering pump 8. The cleaning agent storage tank 9 stores the prepared chemical cleaning solution, and its bottom outlet is connected to the diaphragm metering pump 8, which is connected to the liquid phase outlet of the oxide stripping tower 1. A level gauge 7 is provided on the cleaning agent storage tank 9 to control the liquid level.

[0018] The apparatus for handling blockages in the oxide stripping tower of a methanol-to-olefins unit, as described in this invention, involves the following steps during unit maintenance: During maintenance, a prepared chemical cleaning solution is pumped from the cleaning agent storage tank 9 to the bottom liquid outlet of the oxide stripping tower 1 via a diaphragm metering pump 8. This solution is then pumped into the bottom tray of the oxide stripping tower 1 via a transfer pump 5 and the bottom reflux line 12. A first flow control valve 13 controls the appropriate reflux rate. The chemical cleaning solution is then introduced into the inlet of the reflux pump 4 via a connecting pipeline 10 and injected into the top tray of the oxide stripping tower 1 via a top reflux line 11. A second flow control valve 14 controls the appropriate reflux rate. During this process, the liquid level at the bottom of the oxide stripping tower 1 must be monitored to prevent pump cavitation. The filter 6 is cleaned periodically until it is clean, and the waste chemical cleaning solution is collected and disposed of.

Claims

1. An apparatus for treating blockage in an oxide stripping tower of a methanol-to-olefins plant, comprising an oxide stripping tower (1), characterized in that, The device further includes: A top reflux tank (3) is provided, and the top vapor outlet of the oxide stripping tower (1) is connected to the top reflux tank (3) via a cooler (2). A reflux pump (4) is connected to the bottom liquid phase outlet of the top reflux tank (3), and the reflux pump (4) is connected to the tank area; A top reflux line (11) is connected from the outlet of the reflux pump (4) to the oxide stripping tower (1). A transfer pump (5) is connected to the bottom liquid phase outlet of the oxide stripping tower (1), and the transfer pump (5) is connected to the downstream oxide absorption tower; A bottom reflux line (12) is connected from the outlet of the transfer pump (5) to the oxide stripping tower (1); A cleaning agent storage tank (9) and a diaphragm metering pump (8) are provided, with the bottom outlet of the cleaning agent storage tank (9) connected to the diaphragm metering pump (8), and the diaphragm metering pump (8) connected to the liquid phase outlet of the oxide stripping tower (1). A connecting line (10) is provided, which connects the inlet of the delivery pump (5) and the inlet of the return pump (4).

2. The apparatus for handling blockage in the oxide stripping tower of a methanol-to-olefins unit according to claim 1, characterized in that, A filter (6) is installed on the connecting pipeline (10).

3. The apparatus for handling blockage in the oxide stripping tower of a methanol-to-olefins unit according to claim 1, characterized in that, A second flow control valve (14) is provided on the top return line (11) of the tower.

4. The apparatus for handling blockage in the oxide stripping tower of a methanol-to-olefins unit according to claim 1, characterized in that, The first flow control valve (13) is installed on the bottom return line (12) of the tower.

5. The apparatus for handling blockage in the oxide stripping tower of a methanol-to-olefins unit according to claim 1, characterized in that, The cleaning agent storage tank (9) is equipped with a level gauge (7).

6. The apparatus for handling blockage in the oxide stripping tower of a methanol-to-olefins unit according to claim 1, characterized in that, The top gas phase outlet of the reflux tank (3) is connected to the reactor.

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