Methanol-containing tail gas treatment device

Abstract

The utility model relates to the technical field of tail gas treatment, in particular to a methanol-containing tail gas treatment device which comprises a gas-liquid separation device communicated with a tail gas header pipe, a gas phase of the gas-liquid separation device is communicated with a washing device through a pipeline, and the washing device comprises a primary washing tower and a secondary washing tower. The first-stage washing tower and the second-stage washing tower are connected in series, a circulating washing device is arranged at the bottom of the washing device, and a carbon box is arranged at a gas phase outlet of the second-stage washing tower, so that the content of methanol in tail gas and wastewater is effectively reduced, meanwhile, the treatment flow is optimized, and the resource consumption and the environmental pollution are reduced.

Description

Technical Field

[0001] This utility model relates to the field of exhaust gas treatment technology, specifically to a methanol-containing exhaust gas treatment device. Background Technology

[0002] Methanol-containing exhaust gas refers to the exhaust gas emitted when methanol is used as fuel. As a clean fuel, methanol produces exhaust gas that is more environmentally friendly than traditional fuels during combustion. Methanol combustion produces some gas emissions, mainly including carbon dioxide (CO2), carbon monoxide (CO), nitrogen oxides (NOx), and unburned hydrocarbons (HC).

[0003] However, many methanol combustion processes currently involve incomplete combustion, especially in high-boiling-point solvent production, which generates a large amount of smoke and dust. When the exhaust gas emitted during incomplete combustion of methanol undergoes combustion treatment, some carbon and hydrogen elements in the methanol are oxidized, generating some carbon and hydrogen compounds and other incompletely oxidized organic matter. These substances may form solid particulate matter during combustion, also known as particulate methanol exhaust gas. The emission of such substances to the outside environment will cause pollution. Therefore, methanol-containing exhaust gas needs to be treated before being emitted. Existing exhaust gas treatment devices produce wastewater with high methanol content, causing an increase in COD and BOD of the water body, affecting the water body's self-purification capacity, and leading to water quality deterioration. Furthermore, due to the high methanol content in the treatment process, the amount of adsorbent used increases, leading to an increase in the unit consumption of public works, thus increasing production costs and labor intensity. Therefore, this technical solution is proposed for improvement. Utility Model Content

[0004] The purpose of this invention is to overcome the shortcomings of existing technologies in treating methanol-containing exhaust gas, which are characterized by high costs and poor treatment effects, and to provide a methanol-containing exhaust gas treatment device.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a methanol-containing tail gas treatment device, comprising a gas-liquid separation device connected to the tail gas main pipe, wherein the gas phase of the gas-liquid separation device is connected to a washing device via a pipeline, the washing device comprising a primary washing tower and a secondary washing tower connected in series, a circulating washing device being provided at the bottom of the washing device, and a carbon box being provided at the gas phase outlet of the secondary washing tower.

[0006] Furthermore, the gas-liquid separation device is a condenser, and the liquid phase outlet of the condenser is connected to a wastewater buffer tank.

[0007] Furthermore, the circulating washing device includes a circulating pump located at the bottom, and a washing section is provided inside the circulating washing device. The inlet of the circulating pump is connected to the washing section, and the outlet of the circulating pump is connected to a nozzle located at the top of the circulating washing device via a pipe.

[0008] Furthermore, each of the circulating pumps is arranged in two sets in parallel, and the outlet of each circulating pump is provided with a bypass pipe connected to the sewage buffer tank.

[0009] Furthermore, both the primary and secondary washing towers are equipped with wire mesh demisters at their tops, and both the primary and secondary washing towers are equipped with replenishment pipes at their upper parts, with spray nozzles installed at the outlets of the replenishment pipes.

[0010] Furthermore, the gas phase outlets of both the primary and secondary scrubbing towers are located at the top.

[0011] The beneficial effects of this utility model embodiment are as follows: The washing device consists of a primary washing tower and a secondary washing tower connected in series to form a two-stage washing system. A circulating washing device is configured at the bottom of the washing device, including a circulating pump installed at the bottom of the washing tower. The inlet of the circulating pump is connected to the washing section, and the outlet is connected to a nozzle installed at the top of the washing tower through a pipe to form a circulating spray, which washes the exhaust gas multiple times, improving the methanol removal efficiency. A carbon box is also installed at the gas phase outlet of the secondary washing tower. The carbon box is filled with adsorption materials such as activated carbon to perform deep adsorption treatment on trace amounts of methanol and other harmful gases in the exhaust gas, effectively reducing the methanol content in the exhaust gas and wastewater. At the same time, the treatment process is optimized, reducing resource consumption and environmental pollution. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the overall connection structure of this utility model;

[0013] Figure 2 This is a schematic diagram of the condenser connection structure of this utility model;

[0014] In the diagram: 1. Primary scrubbing tower; 101. Wire mesh demister; 2. Secondary scrubbing tower; 3. Condenser; 4. Carbon box; 5. Circulating pump; 501. Bypass pipe. Detailed Implementation

[0015] The preferred embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely for explaining the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0016] See Figures 1 to 2This utility model discloses a high-efficiency treatment device for methanol-containing tail gas, which mainly includes a gas-liquid separation device connected to the tail gas main pipe. The gas-liquid separation device adopts the form of a condenser 3. Its working principle is to utilize the condensation characteristics of different substances at different temperatures to effectively separate the gas phase and liquid phase in the tail gas. The condensed liquid phase mainly contains some condensed methanol and other high-boiling-point substances, which are transported through pipelines to a sewage buffer tank for temporary storage for further processing.

[0017] The gaseous tail gas after gas-liquid separation is guided to a scrubbing device through pipelines. The scrubbing device consists of a primary scrubbing tower 1 and a secondary scrubbing tower 2 connected in series, forming a two-stage scrubbing system. Each scrubbing tower has a scrubbing section located at the bottom. The scrubbing section is filled with scrubbing liquid, which is located at the bottom of the primary scrubbing tower 1 from the outlet of the condenser 3, ensuring sufficient contact with the tail gas to remove methanol and other harmful gases. To ensure scrubbing effectiveness, a circulating scrubbing device is installed at the bottom of the scrubbing unit, including a circulating pump 5 located at the bottom of the scrubbing tower. The inlet of the circulating pump 5 is connected to the scrubbing section. The outlet is connected to a nozzle located at the top of the scrubbing tower via a pipe. In this way, the scrubbing liquid is drawn from the bottom of the scrubbing tower and transported to the top nozzle by the circulation pump 5, forming a circulating spray to scrub the exhaust gas multiple times and improve the methanol removal efficiency. Considering the stability and reliability in actual operation, two sets of circulation pumps 5 are set in parallel for emergencies. At the same time, the outlet of circulation pump 5 is also equipped with a bypass pipe 501 connected to the sewage buffer tank. When the methanol content in the scrubbing liquid is too high or needs to be replaced, part of the scrubbing liquid can be discharged to the sewage buffer tank through the bypass pipe 501 to avoid burdening subsequent treatment.

[0018] At the top of both the primary scrubbing tower 1 and the secondary scrubbing tower 2, wire mesh demisters 101 are installed to remove foam and fine droplets generated during the scrubbing process, ensuring the cleanliness of the emitted gas. In addition, a replenishment pipe is installed at the top of the scrubbing tower, with a spray nozzle at its outlet, to periodically replenish the scrubbing tower with fresh scrubbing liquid, maintaining the stability of the scrubbing effect. The exhaust gas after two stages of scrubbing is discharged through the gas phase outlet at the top of the secondary scrubbing tower 2. To further ensure that the exhaust gas meets emission standards, a carbon box 4 is also installed at the gas phase outlet of the secondary scrubbing tower 2. The carbon box 4 is filled with activated carbon and other adsorption materials to deeply adsorb trace amounts of methanol and other harmful gases in the exhaust gas, ensuring that the final emitted exhaust gas meets environmental protection requirements. This technical solution effectively reduces the methanol content in exhaust gas and wastewater through multi-stage treatment processes including gas-liquid separation, two-stage scrubbing, circulating spraying, and deep adsorption, while optimizing the treatment process and reducing resource consumption and environmental pollution.

[0019] It should be noted that in the description of this utility model, terms such as "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," which indicate direction or positional relationships, are based on the direction or positional relationships shown in the accompanying drawings. These are used merely for ease of description and do not indicate or imply that the device or element must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0020] Furthermore, it should be noted that, in the description of this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0021] The term "comprising" or any other similar term is intended to cover non-exclusive inclusion, such that a process, article, or apparatus / device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to those processes, articles, or apparatus / devices.

[0022] The technical solution of this utility model has been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the protection scope of this utility model is obviously not limited to these specific embodiments. Without departing from the principle of this utility model, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the protection scope of this utility model.

Claims

1. A methanol-containing tail gas treatment device, characterized in that: The device includes a gas-liquid separation unit connected to the exhaust gas main pipe. The gas phase of the gas-liquid separation unit is connected to a washing unit via a pipeline. The washing unit includes a primary washing tower and a secondary washing tower connected in series. A circulating washing device is provided at the bottom of the washing unit. A carbon box is provided at the gas phase outlet of the secondary washing tower.

2. The methanol-containing tail gas treatment device according to claim 1, characterized in that: The gas-liquid separation device is a condenser, and the liquid phase outlet of the condenser is connected to a sewage buffer tank.

3. The methanol-containing tail gas treatment device according to claim 1, characterized in that: The circulating washing device includes a circulating pump located at the bottom, and a washing section is provided inside the circulating washing device. The inlet of the circulating pump is connected to the washing section, and the outlet of the circulating pump is connected to a nozzle located at the top of the circulating washing device through a pipe.

4. The methanol-containing tail gas treatment device according to claim 3, characterized in that: Each of the circulating pumps is arranged in two sets in parallel, and the outlet of each circulating pump is provided with a bypass pipe connected to the sewage buffer tank.

5. The methanol-containing tail gas treatment device according to claim 1, characterized in that: Both the primary and secondary washing towers are equipped with wire mesh demisters at the top, and both the primary and secondary washing towers are equipped with liquid replenishment pipes at the top, with water spray heads at the outlets of the liquid replenishment pipes.

6. The methanol-containing tail gas treatment device according to claim 1, characterized in that: The gas phase outlets of both the primary and secondary scrubbing towers are located at the top.

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