阅读说明：本技术 一种减缓叔丁醇精制过程含钼催化剂残液堵塞的方法 (Method for relieving residual liquid blockage of molybdenum-containing catalyst in tertiary butanol refining process ) 是由 代平林 陈战涛 王雷 孙健 于 2019-09-24 设计创作，主要内容包括：本发明公开了一种减缓叔丁醇精制过程含钼催化剂残液堵塞的方法,叔丁醇精制装置包括依次连通的第一精馏塔、第一连接管路、第二精馏塔、第二连接管路和蒸发器,第一连接管路上设有第一输送泵,第二连接管路上设有第二输送泵,分别在第一连接管路和第二连接管路上注入防污剂,防污剂包括直连烷烃50～60份、重质石蜡10～20份、长链脂肪醇3～5份和硬脂酸环己胺1～3份,所述份数为质量份数。本发明减缓叔丁醇精制过程含钼催化剂残液堵塞的方法,有效缓解了叔丁醇精制过程含钼催化剂残液堵塞,使得丁醇精制过程中各设备及各管线的使用周期延长了四倍以上；含钼废液的产量减少了一半以上,显著降低了处理成本；提高了塔釜操作温度,提高了叔丁醇的回收率。(The invention discloses a method for slowing down blockage of a molybdenum-containing catalyst residual liquid in a tertiary butanol refining process, wherein a tertiary butanol refining device comprises a first rectifying tower, a first connecting pipeline, a second rectifying tower, a second connecting pipeline and an evaporator which are sequentially communicated, a first conveying pump is arranged on the first connecting pipeline, a second conveying pump is arranged on the second connecting pipeline, and antifouling agents are respectively injected into the first connecting pipeline and the second connecting pipeline and comprise 50-60 parts of direct-connected alkane, 10-20 parts of heavy paraffin, 3-5 parts of long-chain fatty alcohol and 1-3 parts of cyclohexylamine stearate. The method for relieving the blockage of the molybdenum-containing catalyst raffinate in the tertiary butanol refining process effectively relieves the blockage of the molybdenum-containing catalyst raffinate in the tertiary butanol refining process, so that the service cycle of each device and each pipeline in the butanol refining process is prolonged by more than four times; the yield of the molybdenum-containing waste liquid is reduced by more than half, and the treatment cost is obviously reduced; the operation temperature of the tower kettle is improved, and the recovery rate of the tertiary butanol is improved.)

1. A method for slowing down the blockage of the residual liquid of a molybdenum-containing catalyst in the refining process of tertiary butanol is characterized by comprising the following steps: the tertiary butanol refining device comprises a first rectifying tower, a first connecting pipeline, a second rectifying tower, a second connecting pipeline and an evaporator which are sequentially communicated, wherein a first conveying pump is arranged on the first connecting pipeline, a second conveying pump is arranged on the second connecting pipeline, antifouling agents are respectively injected into the first connecting pipeline and the second connecting pipeline, and the antifouling agents comprise 50-60 parts of direct-connected alkane, 10-20 parts of heavy paraffin, 3-5 parts of long-chain fatty alcohol and 1-3 parts of cyclohexylamine stearate, wherein the parts are in parts by mass.

2. The method for mitigating plugging of the molybdenum-containing catalyst raffinate from the refining of tert-butanol according to claim 1, wherein: the antifouling agent also comprises 5-8 parts of diammine and 0.5-2 parts of nonylphenol polyoxyethylene ether, wherein the parts are in parts by weight.

3. The method for mitigating plugging of the molybdenum-containing catalyst raffinate from the refining of tert-butanol according to claim 2, wherein: the carbon number of the straight alkane is C9-C12; the carbon number of the long-chain fatty alcohol is C8-C12.

4. The method for slowing the blockage of the molybdenum-containing catalyst raffinate in the refining process of the tertiary butanol according to any one of claims 1 to 3, which is characterized by comprising the following steps: the mass ratio of the injection amount of the antifouling agent on the first connecting pipeline to the material in the first rectifying tower is 175-200 ppm; the mass ratio of the injection amount of the antifouling agent on the second connecting pipeline to the materials in the second rectifying tower is 230-250 ppm.

5. The method for slowing the blockage of the molybdenum-containing catalyst raffinate in the refining process of the tertiary butanol according to any one of claims 1 to 3, which is characterized by comprising the following steps: a first rectifying tower: the pressure in the tower is 26 +/-2 kpa absolute, the temperature at the bottom of the tower is 80 +/-3 ℃, and the temperature at the top of the tower is 48 +/-3 ℃; a second rectifying tower: the pressure in the tower is 24 +/-2 kpa absolute, the temperature at the bottom of the tower is 83 +/-3 ℃, and the temperature at the top of the tower is 50 +/-3 ℃.

6. The method for slowing the blockage of the molybdenum-containing catalyst raffinate in the refining process of the tertiary butanol according to any one of claims 1 to 3, which is characterized by comprising the following steps: the temperature in the first connecting pipeline is 80 +/-3 ℃, and the pressure is 0.4 +/-0.1 MPa of gauge pressure; the temperature in the second connecting pipeline is 83 +/-3 ℃, and the pressure is 0.8 +/-0.1 MPa gauge pressure.

7. The method for slowing the blockage of the molybdenum-containing catalyst raffinate in the refining process of the tertiary butanol according to any one of claims 1 to 3, which is characterized by comprising the following steps: the tertiary butanol refining device further comprises an antifouling agent tank, the antifouling agent tank is communicated with the first connecting pipeline through a third connecting pipeline, the antifouling agent tank is communicated with the second connecting pipeline through a fourth connecting pipeline, the third connecting pipeline is provided with a first metering pump, and the fourth connecting pipeline is provided with a second metering pump; and a first check valve is arranged on a third connecting pipeline at the downstream of the first metering pump, and a second check valve is arranged on a fourth connecting pipeline at the downstream of the second metering pump.

8. The method for slowing the blockage of the molybdenum-containing catalyst raffinate in the refining process of the tertiary butanol according to any one of claims 1 to 3, which is characterized by comprising the following steps: also comprises a light component recovery tank and a catalyst residue tank; one end of the first connecting pipeline is communicated with the bottom of the side wall of the first rectifying tower, and the other end of the first connecting pipeline is communicated with the middle part of the side wall of the second rectifying tower; one end of the second connecting pipeline is communicated with the bottom of the side wall of the second rectifying tower, and the other end of the second connecting pipeline is communicated with the middle part of the evaporator; the bottom of the evaporator is communicated with the catalyst residue tank through a fifth pipeline, and the top of the evaporator is communicated with the light component recovery tank through a sixth pipeline.

Technical Field

The invention relates to a method for slowing down the blockage of a molybdenum-containing catalyst residual liquid in a tertiary butanol refining process, and belongs to the field of propylene oxide coproduction.

Background

The coproduction process of the propylene oxide/methyl tert-butyl ether (PO/MTBE) mainly comprises peroxidation, epoxidation, TBA/PO (tert-butyl alcohol/propylene oxide) refining, MTBE refining and the like. The PO/MTBE coproduction process comprises the steps of carrying out peroxidation on isobutane and oxygen to generate an intermediate product tert-butyl hydroperoxide (TBHP), carrying out epoxidation reaction on the generated intermediate product tert-butyl hydroperoxide (TBHP) and propylene under the action of a molybdenum-containing catalyst to generate Propylene Oxide (PO) and tert-butyl alcohol (TBA), and reacting the refined TBA with methanol to synthesize MTBE, wherein metal molybdenum residual liquid in the epoxidation reaction can enter a TBA refining unit. After the molybdenum raffinate enters the TBA refining unit, the molybdenum raffinate is easy to accumulate in a tower kettle reboiler, a tower kettle pump and a discharge pipeline, and after the molybdenum raffinate is accumulated to a certain degree, the tower kettle pump and a downstream pipeline are blocked, so that the heat exchange efficiency of a heat exchanger is reduced, and the molybdenum raffinate needs to be frequently switched and processed.

At present, in order to relieve the blockage problem of a tower kettle pump, a discharge pipeline and the like, the recovery rate of effective components can be reduced only by reducing the operation temperature of the tower kettle and improving the discharge flow of the tower kettle, so that the service cycle of a tower kettle reboiler, the tower kettle pump and the discharge pipeline is prolonged. And finally discharging the molybdenum-containing waste liquid entering the TBA refining unit from the epoxidation unit to a catalyst waste liquid tank through a recovery device, and conveying the molybdenum-containing waste liquid to a hazardous waste operation unit for hazardous waste incineration. The designed production amount of the molybdenum-containing waste liquid is about 1.88t/h, calculated according to 8000 hours of annual operation, and 5000 yuan of treatment cost per ton, and the treatment cost of the molybdenum-containing waste liquid is 7500 ten thousand yuan per year, namely, the treatment cost of the molybdenum-containing waste liquid is a huge expense at present. Therefore, there is a need to find a more effective method for preventing the blockage, reducing the amount of the molybdenum-containing waste liquid, and reducing the cost for treating the molybdenum-containing waste liquid.

Disclosure of Invention

In order to solve the problems that during the coproduction of propylene oxide/methyl tert-butyl ether (PO/MTBE), molybdenum raffinate is easy to be dumped after entering a TBA refining unit and the like in the prior art, the invention provides a method for relieving the blockage of the molybdenum-containing catalyst raffinate in the refining process of tert-butyl alcohol.

In order to solve the technical problems, the technical scheme adopted by the invention is as follows:

a method for relieving blockage of a molybdenum-containing catalyst residual liquid in a tertiary butanol refining process is characterized in that a tertiary butanol refining device comprises a first rectifying tower, a first connecting pipeline, a second rectifying tower, a second connecting pipeline and an evaporator which are sequentially communicated, a first conveying pump is arranged on the first connecting pipeline, a second conveying pump is arranged on the second connecting pipeline, and antifouling agents are respectively injected into the first connecting pipeline and the second connecting pipeline and comprise 50-60 parts of direct-connected alkane, 10-20 parts of heavy paraffin, 3-5 parts of long-chain fatty alcohol and 1-3 parts of cyclohexylamine stearate, wherein the parts are parts by mass.

The top discharge of the first rectifying tower and the second rectifying tower is tert-butyl alcohol with purity of more than 95 percent, and the tert-butyl alcohol is sent to react with methanol to generate MTBE.

Before the antifouling agent is not adopted, the treatment capacity of the first rectifying tower is about 100t/h, the concentration of molybdenum-containing waste liquid in the tower kettle discharge is lower, and the service cycle of a tower kettle reboiler and a discharge pipeline is longer; the feeding flow in the second rectifying tower is small, about 6.5-6.6 t/h (most of materials are rectified and separated in the first rectifying tower), the molybdenum-containing waste liquid is concentrated in a tower kettle reboiler and a discharge pipe line, and the operation periods of the tower kettle discharge pipe line, the tower kettle reboiler and the tower kettle discharge pump are short; this application adds the antifouling agent of specific constitution on first connecting line and second connecting line, has effectively alleviated the jam problem of second rectifying column and follow-up pipeline, has reduced the output of molybdenum-containing waste liquid simultaneously, is showing and is reducing treatment cost, has improved tert-butyl alcohol's rate of recovery.

In order to further improve the anti-blocking effect, the anti-fouling agent further comprises 5-8 parts of diammine and 0.5-2 parts of nonylphenol polyoxyethylene ether, wherein the parts are in parts by weight.

In order to further improve the anti-clogging effect, the number of carbon atoms of the straight-chain alkane is preferably from C9 to C12; the carbon number of the long-chain fatty alcohol is C8-C12.

The antifouling agent has the effect of prolonging the service cycle of residual liquid equipment of the molybdenum-containing catalyst; the inventor finds out through research that: for equipment or pipelines containing the molybdenum catalyst raffinate, the antifouling agent plays a role through the oleophilic group and the polar group contained in the antifouling agent, and insoluble solid or liquid substances in materials can be wrapped to form micelles, so that the solubility of the materials to the insoluble solid or liquid substances is improved; meanwhile, the new generated carbon deposition and other solid small particles in the system can be adsorbed to form micelles which are dissolved in the material, and the substances are prevented from being condensed into large particles to be deposited on the surface of equipment; for the dirt which is deposited on the surface of the equipment, the dirt can be stripped and washed by adsorbing the polar group of the dispersing agent on the surface of the dirt.

In order to further improve the anti-blocking effect, the mass ratio of the injection amount of the anti-fouling agent on the first connecting pipeline to the material in the first rectifying tower is 175-200 ppm; the mass ratio of the injection amount of the antifouling agent on the second connecting pipeline to the materials in the second rectifying tower is 230-250 ppm.

In order to increase the purity of the tert-butanol obtained, a first rectification column: the pressure in the tower is 26 +/-2 kpa absolute, the temperature at the bottom of the tower is 80 +/-3 ℃, and the temperature at the top of the tower is 48 +/-3 ℃; a second rectifying tower: the pressure in the tower is 24 +/-2 kpa absolute, the temperature at the bottom of the tower is 83 +/-3 ℃, and the temperature at the top of the tower is 50 +/-3 ℃.

In order to improve the recovery rate of the tertiary butanol and ensure the anti-blocking effect, the temperature in the first connecting pipeline is 80 +/-3 ℃, and the pressure is 0.4 +/-0.1 MPa gauge pressure; the temperature in the second connecting pipeline is 83 +/-3 ℃, and the pressure is 0.8 +/-0.1 MPa gauge pressure.

In order to facilitate feeding, the tert-butyl alcohol refining device further comprises an antifouling agent tank, the antifouling agent tank is communicated with the first connecting pipeline through a third connecting pipeline, the antifouling agent tank is communicated with the second connecting pipeline through a fourth connecting pipeline, the third connecting pipeline is provided with a first metering pump, and the fourth connecting pipeline is provided with a second metering pump; and a first check valve is arranged on a third connecting pipeline at the downstream of the first metering pump, and a second check valve is arranged on a fourth connecting pipeline at the downstream of the second metering pump.

In order to facilitate the treatment, the device also comprises a light component recovery tank and a catalyst residue tank; one end of the first connecting pipeline is communicated with the bottom of the side wall of the first rectifying tower, and the other end of the first connecting pipeline is communicated with the middle part of the side wall of the second rectifying tower; one end of the second connecting pipeline is communicated with the bottom of the side wall of the second rectifying tower, and the other end of the second connecting pipeline is communicated with the middle part of the evaporator; the bottom of the evaporator is communicated with the catalyst residue tank through a fifth pipeline, and the top of the evaporator is communicated with the light component recovery tank through a sixth pipeline. Namely after the material enters a first rectifying tower for rectification, the material discharged from the top of the tower is tertiary butanol with the purity of more than 95 percent, the material discharged from the bottom of the tower is sent to a second rectifying tower, the material discharged from the top of the second rectifying tower is tertiary butanol with the purity of more than 95 percent, the material discharged from the bottom of the tower is sent to an evaporator, and light components in the material are evaporated from the top by the evaporator and sent to a light component recovery tank to be used as fuel; and the material at the bottom of the evaporator is sent to a catalyst residue tank. Under the current operating mode, the catalyst residue jar material is sent to the useless producer of factory external danger and is burned, and the heat of burning can produce partial steam for the heat supply.

Conventional equipment such as a delivery pump, a meter and the like can be arranged on each pipeline according to requirements.

The prior art is referred to in the art for techniques not mentioned in the present invention.

The method for relieving the blockage of the molybdenum-containing catalyst raffinate in the tertiary butanol refining process effectively relieves the blockage of the molybdenum-containing catalyst raffinate in the tertiary butanol refining process, so that the service cycle of each device and each pipeline in the butanol refining process is prolonged by more than four times; the yield of the molybdenum-containing waste liquid is reduced by more than half, and the treatment cost is obviously reduced; the operation temperature of the tower kettle is improved, and the recovery rate of the tertiary butanol is improved.

Drawings

FIG. 1 is a flow diagram of a process for the co-production of propylene oxide/methyl tert-butyl ether (PO/MTBE);

Detailed Description

In order to better understand the present invention, the following examples are further provided to illustrate the present invention, but the present invention is not limited to the following examples.