Hydrogenation tail gas recycling system

Abstract

The utility model provides a hydrogenation tail gas recycling system, relates to the technical field of chemical production, and solves the problem that raw material hydrogen is wasted due to the fact that hydrogenation tail gas cannot be recycled in the existing process. The device comprises a hydrogenated tail gas separation pipeline connected to a tail gas separation outlet of a hydrogenated liquid storage tank, the hydrogenated tail gas separation pipeline is connected with an oxygen content analysis detector, the hydrogenated tail gas separation pipeline is connected with a first branch pipe and a second branch pipe in a split-flow mode, the first branch pipe is connected with a first stop valve, and the second branch pipe is connected with a second stop valve. The second branch pipe is connected with a second stop valve, an outlet of the first branch pipe is connected to an incineration device, and an outlet of the second branch pipe is sequentially connected with a gas-liquid separator, a vacuum pump, a desorption gas mixing tank, a compressor and a second-section adsorption system. The hydrogenation tail gas recycling device has the beneficial effect that hydrogenation tail gas can be better recycled.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of chemical production, specifically relates to hydrogenation tail gas recycling system. BACKGROUND

[0002] In hydrogen peroxide production process, hydrogenation liquid in hydrogenation liquid storage tank contains dissolved hydrogen and nitrogen gas, which is resolved in normal pressure hydrogenation liquid storage tank, then hydrogenation tail gas is condensed, separated and recycled aromatic hydrocarbon in gas, separated gas is discharged to incineration device by hydrogenation tail gas fan for treatment, hydrogen content in resolved gas is about 50~90%, maximum amount of two sets of resolved gas is about 2000m3 / h, wherein hydrogen amount of 1000~1500m3 / h should be folded; the existing process lacks hydrogenation tail gas recycling, which causes raw material hydrogen waste. CONTENT OF UTILITY MODEL

[0003] The utility model discloses a hydrogenation tail gas recycling system, which can recycle hydrogenation tail gas and reduce the waste of raw material hydrogen.

[0004] To achieve the above object, the utility model adopts the following technical scheme:

[0005] Hydrogenation tail gas recycling system, characterized by: including the hydrogenation tail gas resolution pipeline connected in the hydrogenation liquid storage tank tail gas resolution export, hydrogenation tail gas resolution pipeline is connected with oxygen content analysis detector, hydrogenation tail gas resolution pipeline is shunt connected with first branch pipe, second branch pipe, first branch pipe is connected with first cut-off valve, second branch pipe is connected with second cut-off valve, first branch pipe export is connected to incineration device, and the export of second branch pipe is connected with gas-liquid separator, vacuum pump, resolved gas mixing tank, compressor and two-stage adsorption system in proper order.

[0006] Further improvement is: the export of second branch pipe is connected with the gas inlet of gas-liquid separator, the gas outlet of gas-liquid separator is connected with the gas inlet of vacuum pump, the gas outlet of vacuum pump is connected with the gas inlet of resolved gas mixing tank, the gas outlet of resolved gas mixing tank is connected with the gas inlet of compressor, and the gas outlet of compressor is connected with the gas inlet of two-stage adsorption system.

[0007] Further improvement is: the liquid outlet of gas-liquid separator is connected with the water inlet of water treatment system.

[0008] Further improvement is: the gas-liquid separator is a gas-liquid separator with condensing mechanism.

[0009] Further improvement is: the second branch pipe between vacuum pump and second cut-off valve is connected with check valve.

[0010] Further improvement is that the compressor is a screw compressor.

[0011] Further improvement is that the oxygen content analysis detector is provided with at least two.

[0012] Further improvement is that the oxygen content analysis detector is provided with at least two.

[0013] Further improvement is that the first cut-off valve is a FO valve, and the second cut-off valve is a FC valve.

[0014] After the above technical scheme is adopted, the following beneficial effects are obtained compared with the prior art:

[0015] The hydrogenated tail gas can be recycled and reused by the oxygen content analysis detector and the additionally added second branch pipe, so that waste of hydrogen gas is avoided, and consumption of hydrogen gas is reduced.

[0016] Since the molecular sieve in the PSA adsorption tower in the two-stage adsorption system will react with liquid water, the molecular sieve is deactivated, so the gas-liquid separator is additionally added to remove water in the tail gas, so that subsequent adsorption is ensured to proceed, the effect is improved, and the service life of the equipment is prolonged.

[0017] The oxygen content analysis detector provided with at least two can select one from two detection devices, one of which is directly interlocked, so that normal operation can be ensured in the case of failure of one of the two. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical scheme in the embodiments of the present application or the prior art, the drawings needed in the following embodiment or prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0019] Fig. 1 is a structural schematic diagram of the present application;

[0020] Fig. 2 is a circuit principle structure schematic diagram of the present application.

[0021] Legend: hydrogenation liquid storage tank 1, hydrogenation tail gas precipitation pipeline 2, first branch pipe 21, second branch pipe 22, first cut-off valve 23, second cut-off valve 24, check valve 25, oxygen content analysis detector 3, gas-liquid separator 4, vacuum pump 5, analysis gas mixing tank 6, compressor 7, two-stage adsorption system 8. DETAILED DESCRIPTION

[0022] Referring to Figs. 1-2 The technical scheme adopted in the specific embodiment is shown in the drawings: a hydrogenated tail gas recycling system, comprising a hydrogenated tail gas outlet pipeline 2 connected to a tail gas outlet of a hydrogenated liquid storage tank 1, an oxygen content analysis detector 3 connected to the hydrogenated tail gas outlet pipeline 2, a first branch pipeline 21 and a second branch pipeline 22 connected in parallel to the hydrogenated tail gas outlet pipeline 2, a first shut-off valve 23 connected to the first branch pipeline 21, a second shut-off valve 24 connected to the second branch pipeline 22, an outlet of the first branch pipeline 21 connected to a combustion device, and an outlet of the second branch pipeline 22 connected in sequence to a gas-liquid separator 4, a vacuum pump 5, a desorption gas mixing tank 6, a compressor 7, and a two-stage adsorption system 8.

[0023] The outlet of the second branch pipeline 22 is connected to the gas inlet of the gas-liquid separator 4, the gas outlet of the gas-liquid separator 4 is connected to the gas inlet of the vacuum pump 5, the gas outlet of the vacuum pump 5 is connected to the gas inlet of the desorption gas mixing tank 6, the gas outlet of the desorption gas mixing tank 6 is connected to the gas inlet of the compressor 7, and the gas outlet of the compressor 7 is connected to the gas inlet of the two-stage adsorption system 8.

[0024] The liquid outlet of the gas-liquid separator 4 is connected to the water inlet of a water treatment system.

[0025] The gas-liquid separator 4 is a gas-liquid separator with a condensing mechanism. Since the molecular sieve in the PSA adsorption tower in the two-stage adsorption system reacts with liquid water, causing the molecular sieve to be deactivated, a gas-liquid separator 4 is added to remove water from the tail gas, ensuring the subsequent adsorption process, improving the effect, and prolonging the service life of the equipment.

[0026] The compressor 7 is a screw compressor.

[0027] The first shut-off valve 23 is an FO valve, and the second shut-off valve 24 is an FC valve. The FO valve is opened in the case of failure when going to the combustion device, and the FC valve is closed in the case of failure when going to the two-stage adsorption system PSA.

[0028] The oxygen content analysis detector 3 is provided with at least two. The oxygen content analysis detector 3 is provided with at least two.

[0029] The controller is electrically connected to the first shut-off valve 23, the second shut-off valve 24, the gas-liquid separator 4, the vacuum pump 5, and the compressor 7. The controller is a single-chip microcomputer controller.

[0030] The utility model discloses a working principle: when using, be provided with oxygen content analysis detector on hydrogenation tail gas precipitation pipeline, detect on-line oxygen content analysis data, judge tail gas flow direction through analysis data, and the content lower passes through the opening first cut -out valve and flows to incineration device direct incineration emptying, and the content higher opens second cut -out valve, first through gas -liquid separator to remove the moisture in tail gas, then through second branch pipe flow direction vacuum pump pressurization, subsequently send into to two stage adsorption system and carry out further recycling, because the molecular sieve in the PSA adsorption tower in two stage adsorption system will react to liquid water, leads to molecular sieve deactivation, so add gas -liquid separator to remove the water in tail gas, guarantee the subsequent adsorption and carry out, improve effect, prolong the service life of equipment, be provided with at least two oxygen content analysis detector can be in two detection equipment two take one, and one alarm direct interlock, under the condition of one of them fails, still can normally operate.

[0031] The above shows and describes the basic principle and main features of the utility model and its advantages, and the skilled person in the art should understand that the utility model is not limited by the above examples, and the above examples and description only illustrate the principle of the utility model, and various changes and improvements can be made to the utility model without departing from the spirit and scope of the utility model, and these changes and improvements all fall within the scope of the claimed utility model, and the scope of protection of the utility model is defined by the appended claims and their equivalents. The utility model is not described in detail, and all known technologies of the skilled person in the art are known.

Claims

1. A hydrogenated tail gas recycle system characterized by: The hydrogenation tail gas discharge pipeline connected to the hydrogenation liquid tank tail gas discharge outlet is provided with an oxygen content analysis detector, and is branched to be connected to a first branch pipeline and a second branch pipeline.

2. The hydrogenated tail gas recycle system of claim 1, wherein: The outlet of the second branch pipeline is connected to the gas inlet of the gas-liquid separator, the gas outlet of the gas-liquid separator is connected to the gas inlet of the vacuum pump, the gas outlet of the vacuum pump is connected to the gas inlet of the desorption gas mixing tank, the gas outlet of the desorption gas mixing tank is connected to the gas inlet of the compressor, and the gas outlet of the compressor is connected to the gas inlet of the two-stage adsorption system.

3. The hydrogenated tail gas recycle system of claim 2, wherein: The liquid outlet of the gas-liquid separator is connected to the water inlet of the water treatment system.

4. The hydrogenated tail gas recycle system of claim 1, wherein: The gas-liquid separator is a gas-liquid separator with a condensing mechanism.

5. The hydrogenated tail gas recycle system of claim 1, wherein: A check valve is connected to the second branch pipeline between the vacuum pump and the second cut-off valve.

6. The hydrogenated tail gas recycle system of claim 1, wherein: The compressor is a screw compressor.

7. The hydrogenated tail gas recycle system of claim 1, wherein: The oxygen content analysis detector is provided with at least two.

8. The hydrogenated tail gas recycle system of claim 1, wherein: The first cut-off valve is an FO valve, and the second cut-off valve is an FC valve.

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