Device for monitoring content of dimethyl ether in chloromethane synthesis gas on line

Abstract

The utility model provides a device for on-line monitoring of dimethyl ether content in chloromethane synthesis gas, which comprises a first rectifying tower, a first sampling pipeline arranged at the top of the first rectifying tower is communicated with on-line analysis equipment, and the on-line analysis equipment is sequentially communicated with a buffer tank, a compressor, a first reboiler and the first rectifying tower through pipelines. The top of the first rectifying tower is also sequentially communicated with a first heat exchanger, a second heat exchanger and a second absorption tower through pipelines, the first heat exchanger and the second heat exchanger are respectively communicated with a reflux condensation tank through pipelines, and the bottom of the reflux condensation tank is communicated with the first rectifying tower and an extraction pipeline through pipelines via a reflux pump. According to the utility model, a direct sampling method is replaced by a special sampling method, so that the influence of human factors of the direct sampling method is solved, the sampling is carried out under a closed condition, personnel injury is effectively avoided, a sample result more accurately reflects the actual operation condition of the chloromethane synthesis device, and the content of dimethyl ether is ensured to be within a control range.

Description

TECHNICAL FIELD

[0001] The utility model relates to a chemical industry technical field especially relates to a device of on -line monitoring dimethyl ether content in chloromethane synthesis gas. BACKGROUND

[0002] Chloromethane is also called methyl chloride, is important raw material of organic synthesis, is mainly used to produce organic silicon compound - methyl chlorosilane, and methyl cellulose, still is widely used as solvent, extracting agent, propellant, refrigerant, local anesthetic, methylating reagent, and is used to produce pesticide, medicine, spice etc. What is the adverse effect of dimethyl ether (dimethyl ether is the byproduct of chloromethane synthesis, and dimethyl ether content reflects the selectivity of synthesis reaction, and the sulfuric acid consumption required for subsequent removal of dimethyl ether) analysis sampling type includes: one, direct sampling method;Two, indirect sampling method. Direct sampling method is directly collected by manual, is suitable for simple, easy to collect sample;But sampling process is greatly influenced by human factors, and there is sample distortion. Indirect sampling method is completed through certain device and instrument, and the operation is relatively complex, and is influenced by equipment and operating conditions, and the sample representativeness is better. SUMMARY

[0003] In order to solve the above problems, the utility model aims at providing a device of on -line monitoring dimethyl ether content in chloromethane synthesis gas.

[0004] The utility model technical scheme is as follows:

[0005] A device of on -line monitoring dimethyl ether content in chloromethane synthesis gas, the device includes first rectifying tower, and first rectifying tower top is equipped with first sampling pipeline and is communicated with on -line analysis equipment, and on -line analysis equipment is communicated with buffer tank, compressor, first reboiler and first rectifying tower in sequence through pipeline, and the top of first rectifying tower is also communicated with first heat exchanger, second heat exchanger and second absorption tower in sequence through pipeline, and first heat exchanger, second heat exchanger are communicated with reflux condenser tank through pipeline respectively, and the bottom of reflux condenser tank is communicated with first rectifying tower and production pipeline through pipeline by reflux pump, and the gas phase vent line of second heat exchanger is communicated with the vent line of on -line analysis equipment and second absorption tower.

[0006] Preferably, the first heat exchanger discharge port is communicated with the reflux condenser tank through the pipeline.

[0007] Preferably, the bottom of the second absorption tower is connected to the top of the second absorption tower through a circulation pump, a third heat exchanger, and a second absorption tower by a circulation pipeline.

[0008] Preferably, the first reboiler and the bottom and lower part of the first rectifying tower form a loop, and the first reboiler is also connected to the middle part of the first rectifying tower through a pipeline.

[0009] Preferably, the reflux pump is also in communication with the upper portion of the first rectification tower through a pipeline.

[0010] Preferably, the online analysis device is an online chromatographic analyzer.

[0011] The utility model has the advantages of:

[0012] The utility model discloses a special sampling method replaces direct sampling method, solves the influence of direct sampling method artificial factor, and sampling is carried out under the closed condition, effectively avoids personnel injury, and sample result is more accurate to reflect the actual operation condition of chloromethane synthesis device, ensures that dimethyl ether content is in the control range. BRIEF DESCRIPTION OF DRAWINGS

[0013] Figure 1 It is the device structure schematic diagram of detecting the chloride ion in methanol;

[0014] In the drawing: first rectification tower 1, first sampling pipeline 2, buffer tank 3, compressor 4, first reboiler 5, first heat exchanger 6, second heat exchanger 7, second absorption tower 8, reflux condenser 9, reflux pump 10, online analysis device vent line 11, circulating pump 12, third heat exchanger 13. DETAILED DESCRIPTION

[0015] The technical scheme in the utility model embodiment will be clearly and completely described below in combination with specific embodiments of the utility model, and the embodiments are only a part of the embodiments of the utility model, not all the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by the person skilled in the art without creative labor belong to the protection scope of the utility model.

[0016] Embodiment 1

[0017] An online monitoring device of dimethyl ether content in chloromethane synthesis gas, the device includes first rectification tower 1, first rectification tower 1 top is equipped with first sampling pipeline 2 and is communicated with online analysis device, and online analysis device is communicated with buffer tank 3, compressor 4, first reboiler 5 and first rectification tower 1 in proper order through pipeline, the top of first rectification tower 1 is also communicated with first heat exchanger 6, second heat exchanger 7 and second absorption tower 8 in proper order through pipeline, first heat exchanger 6, second heat exchanger 7 are communicated with reflux condenser 9 through pipeline respectively, the bottom of reflux condenser 9 is communicated with first rectification tower 1 and production pipeline through reflux pump 10 through pipeline, second heat exchanger 7 gas phase vent line is communicated with online analysis device vent line 11 and second absorption tower 8.

[0018] Preferably, the first heat exchanger 6 outlet is communicated with the reflux condenser 9 through a pipeline.

[0019] Preferably, the second absorption tower 8 bottom is communicated with the second absorption tower 8 top through a pipeline, a circulating pump 12 and a third heat exchanger 13 to form a circulating pipeline.

[0020] Preferably, the first reboiler 5 is communicated with the first rectifying tower 1 bottom and lower part to form a loop, and the first reboiler 5 is also communicated with the first rectifying tower 1 middle part through a pipeline.

[0021] Preferably, the reflux pump 10 is also communicated with the first rectifying tower 1 upper part through a pipeline.

[0022] Preferably, the online analysis device is an online chromatographic analyzer, model: 241102, Lanzhou Kehai Petrochemical Equipment Co., Ltd.

[0023] A sample is drawn from a high-pressure position of the first rectifying tower 1 top, and is returned to the compressor 4 inlet buffer tank 3 through a large circulation; the large circulation draws a three-way sample to the online analysis device, and the treated gas is returned to the second absorption tower 8 for absorption treatment; the online analysis device analyzes the chloromethane sample, and obtains that the dimethyl ether content in the chloromethane synthesis gas is less than 0.0030%, and the synthesis gas component content meets the requirement.

[0024] The technical scheme of the present application is explained by the above embodiment, but the present application is not limited to the above embodiment, that is, it does not mean that the present application must rely on the above specific embodiment to be implemented. Any improvement on the basis of the present application by the person skilled in the art, or equivalent replacement of the materials selected by the present application, etc., all fall within the protection scope of the patent.

Claims

1. A device for online monitoring of the dimethyl ether content in a chloromethane synthesis gas, said device comprising a first rectification column (1), characterized in that: The first rectifying tower (1) is provided with a first sampling pipeline (2) at the top and is communicated with an online analysis device, the online analysis device is communicated with a buffer tank (3), a compressor (4), a first reboiler (5) and the first rectifying tower (1) in sequence through a pipeline, the first rectifying tower (1) is further communicated with a first heat exchanger (6), a second heat exchanger (7) and a second absorption tower (8) in sequence through a pipeline, the first heat exchanger (6) and the second heat exchanger (7) are communicated with a reflux condenser tank (9) through a pipeline respectively, the bottom of the reflux condenser tank (9) is communicated with the first rectifying tower (1) and a production pipeline through a reflux pump (10) through a pipeline, a gas phase venting pipeline of the second heat exchanger (7) is communicated with an online analysis device venting pipeline (11) and the second absorption tower (8).

2. The apparatus for on-line monitoring of dimethyl ether content in chloromethane synthesis gas according to claim 1, characterized in that: The first heat exchanger (6) is communicated with the reflux condenser tank (9) through a pipeline.

3. The apparatus for on-line monitoring of dimethyl ether content in chloromethane synthesis gas according to claim 1, characterized in that: The bottom of the second absorption tower (8) forms a circulation pipeline through a circulation pump (12), a third heat exchanger (13) and the top of the second absorption tower (8) through a pipeline.

4. The apparatus for on-line monitoring of dimethyl ether content in chloromethane synthesis gas according to claim 1, characterized in that: The first reboiler (5) forms a loop with the bottom and the lower part of the first rectifying tower (1), and the first reboiler (5) is further communicated with the middle part of the first rectifying tower (1) through a pipeline.

5. The apparatus for on-line monitoring of dimethyl ether content in chloromethane synthesis gas according to claim 1, characterized in that: The reflux pump (10) is further communicated with the upper part of the first rectifying tower (1) through a pipeline.

6. The apparatus for on-line monitoring of dimethyl ether content in chloromethane synthesis gas according to claim 1, characterized by: The online analysis device is an online chromatographic analyzer.

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