CN210874717U

CN210874717U - Tail gas treatment system in polyether production

Info

Publication number: CN210874717U
Application number: CN201921549207.9U
Authority: CN
Inventors: 赵其献; 郭康宁; 陶玉环; 李汝阁; 康春花
Original assignee: Sinomec Refinery & Chemical Corp ltd
Current assignee: Sinomec Refinery & Chemical Corp ltd
Priority date: 2019-09-17
Filing date: 2019-09-17
Publication date: 2020-06-30
Anticipated expiration: 2029-09-17

Abstract

The utility model provides a tail gas processing system in polyether production, including compressor, condenser, liquid trap, absorption tower A and absorption tower B that connect in order, absorption tower A and absorption tower B's packing layer upper portion all is equipped with the washing liquid entry, the washing liquid entry all with the cooler is linked together, absorption tower A all is equipped with the overflow mouth with absorption tower B, absorption tower A overflow mouth is higher than its gas inlet A, absorption tower B overflow mouth is less than its gas inlet B. This tail gas processing system in polyether production clears away the tail gas composition that traditional washing mode is difficult to handle through pressurization cooling procedure, reduces the absorption pressure of filler in the absorption tower, improves tail gas purifying effect, and unique two tower designs, can be different according to handling tail gas volume and tail gas concentration, and the service mode of adjustment two towers has adapted to different operating condition, and energy-conservation, water conservation.

Description

Tail gas treatment system in polyether production

Technical Field

The utility model relates to a chemical industry environmental protection technical field especially relates to a tail gas treatment system in polyether production.

Background

At present, with the rapid development of national economy, the requirement on environmental protection is higher and higher. The Tianjin City of 8/1/2014 starts to implement the emission control Standard of volatile organic Compounds of Industrial enterprises (DB12/524-³(maximum incineration treatment is 20 mg/m)³)。

The main composition is nitrogen gas in the tail gas that produces in the polyether production process, epoxypropane, acrylonitrile, styrene etc. that the belt exceeds standard are difficult to handle, in traditional polyether production tail gas treatment, generally adopt the mode of water washing or alkali-wash, however, styrene, acrylonitrile among the polyether tail gas are insoluble in water or slightly soluble in water, traditional water washing's mode is difficult to clear away, and polyether micromolecule etc. in the tail gas can condense into viscous liquid after water washing or alkali-wash, block up the filler in the absorption tower easily, in case block up, can lead to the device to shut down, tail gas can't be handled.

Disclosure of Invention

In view of this, the utility model aims at overcoming the defect that exists among the above-mentioned prior art, provides a tail gas treatment system in polyether production.

In order to achieve the above purpose, the technical scheme of the utility model is realized like this:

a tail gas treatment system in polyether production comprises a compressor, a condenser, a liquid collector, an absorption tower A and an absorption tower B which are sequentially connected, wherein the upper parts of packing layers of the absorption tower A and the absorption tower B are respectively provided with a washing liquid inlet, and the washing liquid inlets are respectively communicated with a cooler;

the absorption tower A and the absorption tower B are both provided with overflow ports, the overflow port of the absorption tower A is higher than the gas inlet A, and the overflow port of the absorption tower B is lower than the gas inlet B;

and a circulating pump B attached to the absorption tower B is provided with two water outlet pipes, wherein one water outlet pipe is communicated with the absorption tower B, and the other water outlet pipe is communicated with the top of the absorption tower A.

Further, a condensate outlet is formed in the lower portion of the condenser.

Further, an induced draft fan is arranged between the gas outlet A at the top of the absorption tower A and the gas inlet B of the absorption tower B.

Further, a pressure regulating valve is arranged on an air outlet arranged at the top of the liquid collector.

Furthermore, a gas ejector pipe is arranged at the gas inlet A, and a nozzle is arranged on the gas ejector pipe.

Furthermore, a U-shaped pipe is arranged outside the overflow port, and an air-tight water layer is arranged at the bottom of the U-shaped pipe.

Further, the top of the absorption tower B is provided with an activated carbon adsorption tank.

Compared with the prior art, the beneficial effects of the utility model are as follows:

this tail gas processing system in polyether production clears away the tail gas composition that traditional washing mode is difficult to handle through pressurization cooling procedure, reduces the absorption pressure of filler in the absorption tower, improves tail gas purifying effect, and unique two tower designs, can be different according to handling tail gas volume and tail gas concentration, and the using-way of adjustment two towers both can establish ties by two towers and also can single tower operation, has adapted to different operating condition, and energy-conservation, water conservation.

Drawings

The accompanying drawings, which form a part hereof, are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention without undue limitation. In the drawings:

fig. 1 is a schematic diagram of the overall structure of a tail gas treatment system in polyether production.

Description of reference numerals:

1-a compressor; 2-a condenser; 21-a condensate outlet; 22-gas outlet; 3-a liquid collector; 31-an air inlet; 32-air outlet; 33-a pressure regulating valve; 4-absorption column a; 41-gas inlet a; 411-a gas lance; 42-gas outlet A; 43-circulation pump A; 431-water outlet; 5-a draught fan; 6-absorption column B; 61-gas inlet B; 62-gas outlet B; 63-circulating pump B; 64-an activated carbon adsorption tank; 7-a filler layer; 8-an overflow port; 9-a cooler; 91-washing liquid inlet.

Detailed Description

It should be noted that, in the present invention, the embodiments and features of the embodiments may be combined with each other without conflict.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are used merely for convenience of description and for simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be construed as limiting the present invention. Furthermore, the terms "first", "second", etc. are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first," "second," etc. may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless otherwise specified.

In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art through specific situations.

The invention will be described in detail with reference to the following examples with reference to the accompanying drawings:

the tail gas treatment system in polyether production comprises a compressor 1, a condenser 2, a liquid collector 3, an absorption tower A4 and an absorption tower B6 which are connected in sequence, wherein the upper parts of a filler layer 7 of the absorption tower A4 and the absorption tower B6 are communicated with a cooler 9, washing liquid is cooled to 1-10 ℃ by the cooler 9 and then is injected into the absorption tower A4 and the absorption tower B6 through a washing liquid inlet 91, and the absorption tower A and the absorption tower B are respectively provided with a circulating pump for conveying the washing liquid flowing into the bottom of the tower back to the upper part of the filler layer 7 of the top of the tower to form circulation of the washing liquid in the tower.

The lower part of the condenser 2 is provided with a condensate outlet 21, the upper part is provided with a gas outlet 22, the gas outlet 22 is communicated with a gas inlet 31 in the middle of the liquid collector 3, the gas outlet 32 arranged at the top of the liquid collector 3 is communicated with a gas inlet A41 arranged in the absorption tower A4, a pressure regulating valve 33 is arranged on the air outlet 32, an air injection pipe 411 is arranged at the air inlet A41, the gas injection pipe 411 is provided with a nozzle, the absorption tower A4 and the absorption tower B6 are both provided with overflow ports 8, a U-shaped pipe is arranged outside the overflow port 8, a choke water layer is arranged at the bottom of the U-shaped pipe to prevent tail gas in the absorption tower A4 from leaking outside, the overflow port 8 of the absorption tower A4 is higher than the gas injection pipe 411, that is, the gas injection pipe 411 is immersed in the washing liquid, and since the impurity concentration of the tail gas is reduced after the tail gas is washed in the absorption tower a, it is not necessary to provide a gas injection pipe in the absorption tower B, and the tail gas is not immersed in the washing liquid when entering the absorption tower B.

After the tail gas is pressurized by the compressor 1 and cooled to 1-10 ℃ by the condenser 2, most of propylene oxide, styrene and acrylonitrile can be condensed out, condensate flows out from a condensate outlet at the lower part of the condenser, the rest of the tail gas enters a liquid collector from a gas outlet at the upper part of the condenser through a gas conveying pipe, the liquid collector absorbs the residual condensate in the tail gas, a gas inlet at the middle part of the liquid collector is communicated, polyether micromolecules are basically removed, the rest of the tail gas enters a gas outlet pipe of the absorption tower A4 after pressure adjustment, residual VOCS in the tail gas is removed through water washing or alkali washing in the tower, the temperature of the washing liquid in the absorption tower A4 is 1-10 ℃, the pressure in the gas spraying pipe 411 is larger than that in the absorption tower A, after the tail gas overflows from the washing liquid, countercurrent heat exchange and mass transfer are carried out on the washing liquid in the tower, and then the tail.

Under the condition that the tail gas concentration is small or the tail gas quantity is small, the tail gas can be discharged after being treated by the absorption tower A4, and under the condition that the tail gas concentration is large or the tail gas quantity is large, the gas discharged from the top of the absorption tower A4 needs to be conveyed into the absorption tower B6 through the induced draft fan 5 for secondary treatment.

Namely, the tail gas discharged from the gas outlet a42 is input into the absorption tower B6 through the induced draft fan 5, and is subjected to countercurrent heat exchange and mass transfer with the washing liquid in the absorption tower B6, and then is discharged from the gas outlet B62 at the top of the absorption tower B6, and the top of the absorption tower B6 is provided with the activated carbon adsorption tank 64 for absorbing pollutants possibly existing in the tail gas and preventing the single gas component from exceeding the standard.

And a circulating pump B63 attached to the absorption tower B6 is provided with two water outlet pipes, wherein one water outlet pipe is communicated with the absorption tower B6, and the other water outlet pipe is communicated with the top of the absorption tower A4, so that the washing liquid in the absorption tower B6 is input into the absorption tower A4 under the condition that the absorption tower B6 is not used for a while, and the washing liquid is recycled.

The cooler, the condenser, the liquid collector and the absorption tower are all in the prior art, and the internal structure of the absorption tower is not described any more.

The above description is only a preferred embodiment of the present invention, and should not be taken as limiting the invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The tail gas treatment system in polyether production is characterized by comprising a compressor (1), a condenser (2), a liquid collector (3), an absorption tower A (4) and an absorption tower B (6) which are sequentially connected, wherein washing liquid inlets (91) are formed in the upper parts of packing layers (7) of the absorption tower A (4) and the absorption tower B (6), and the washing liquid inlets (91) are communicated with a cooler (9);

the absorption tower A (4) and the absorption tower B (6) are both provided with overflow ports (8), the overflow ports (8) of the absorption tower A (4) are higher than the gas inlet A (41) of the absorption tower A, and the overflow ports (8) of the absorption tower B (6) are lower than the gas inlet B (61) of the absorption tower B;

and a circulating pump B (63) attached to the absorption tower B (6) is provided with two water outlet pipes, wherein one water outlet pipe is communicated with the absorption tower B (6), and the other water outlet pipe is communicated with the top of the absorption tower A (4).

2. The tail gas treatment system in polyether production according to claim 1, characterized in that: and a condensate outlet (21) is formed in the lower part of the condenser (2).

3. The tail gas treatment system in polyether production according to claim 1, characterized in that: and an induced draft fan (5) is arranged between a gas outlet A (42) at the top of the absorption tower A (4) and a gas inlet B (61) of the absorption tower B (6).

4. The tail gas treatment system in polyether production according to claim 1, characterized in that: a pressure regulating valve (33) is arranged on an air outlet (32) arranged at the top of the liquid collector (3).

5. The tail gas treatment system in polyether production according to claim 1, characterized in that: the gas inlet A (41) is provided with a gas injection pipe (411), and a nozzle is arranged on the gas injection pipe (411).

6. The tail gas treatment system in polyether production according to claim 1, characterized in that: and a U-shaped pipe is arranged outside the overflow port (8), and an air-tight water layer is arranged at the bottom of the U-shaped pipe.

7. The tail gas treatment system in polyether production according to claim 1, characterized in that: and the top of the absorption tower B (6) is provided with an activated carbon adsorption tank (64).