阅读说明：本技术 一种环己醇脱氢产品急冷和脱水工艺方法 (Quenching and dewatering process method for cyclohexanol dehydrogenation product ) 是由 李广忠 刘新伟 杨克俭 李岩 王刚 李坤 黄贺源 于 2021-10-13 设计创作，主要内容包括：本发明提供了一种环己醇脱氢产品急冷和脱水工艺方法,设计一种环己醇脱氢产品急冷和脱水设备,包括醇酮干燥塔、醇酮干燥冷凝器、一级回流罐、醇酮干燥尾冷器、二级回流罐。本发明所述的工艺方法将环己醇脱氢产物进入醇酮干燥塔进行急冷并分离氢气,塔顶分别设置冷凝器、尾冷器分级冷凝,并设置两级回流罐,冷凝器和一级回流罐中的物料全回流,尾冷器冷凝的物料在二级回流罐中倾析,油相送至一级回流罐,水相送至污水处理,塔釜得到饱和温度且含水量满足分离要求的粗醇酮,送至下游分离装置,使用本发明中的工艺方法可以节约循环水和精馏分离单元蒸汽消耗,降低能源消耗,减少生产成本,具有广泛的应用前景。(The invention provides a cyclohexanol dehydrogenation product quenching and dehydrating process method, and designs cyclohexanol dehydrogenation product quenching and dehydrating equipment which comprises an alcohol ketone drying tower, an alcohol ketone drying condenser, a primary reflux tank, an alcohol ketone drying tail cooler and a secondary reflux tank. The process method of the invention can save steam consumption of circulating water and a rectification separation unit, reduce energy consumption and production cost, and has wide application prospect.)

1. A cyclohexanol dehydrogenation product rapid cooling and dehydration equipment which characterized in that: the device comprises an alcohol ketone drying tower, wherein a middle feeding hole of the alcohol ketone drying tower is communicated with a discharging hole of a cyclohexanol dehydrogenation reactor;

the feed inlet of the alcohol ketone drying condenser is communicated with the gas outlet at the top of the alcohol ketone drying tower;

the feed inlet of the primary reflux tank is communicated with the liquid phase discharge port of the alcohol ketone drying condenser, and the discharge port of the primary reflux tank is communicated with the feed inlet at the top of the alcohol ketone drying condenser;

the feed inlet of the alcohol ketone drying tail cooler is communicated with the gas-phase discharge outlet of the alcohol ketone drying condenser;

and the feed inlet of the second-stage reflux tank is communicated with the liquid-phase discharge outlet of the alcohol-ketone drying tail cooler, and the oil-phase discharge outlet of the second-stage reflux tank is communicated with the feed inlet of the first-stage reflux tank.

2. The apparatus of claim 1, wherein: and a reflux pump is communicated between the primary reflux tank and the alcohol ketone drying tower.

3. The apparatus of claim 1, wherein: and a gas-phase discharge port of the alcohol ketone drying tail cooler is communicated with a dehydrogenation compressor.

4. The apparatus of claim 1, wherein: and a discharge port at the bottom of the alcohol ketone drying tower is communicated with a feed inlet of the light component removal tower.

5. A cyclohexanol dehydrogenation product quenching and dehydration process, using the apparatus of any of claims 1-4, characterized by the following steps:

(1) the gas-liquid mixed product discharged from the cyclohexanol dehydrogenation reactor enters an alcohol ketone drying tower, the gas phase discharged from the top of the alcohol ketone drying tower enters an alcohol ketone drying condenser, and crude alcohol ketone is discharged from the tower kettle;

(2) condensed liquid formed by condensation of the alcohol ketone drying condenser enters a primary reflux tank, and uncondensed gas phase enters an alcohol ketone drying tail air cooler;

(3) condensed fluid formed by condensation of the alcohol ketone drying tail cooler enters a secondary reflux tank and is layered into a water layer and an oil layer in the secondary reflux tank, and the oil layer enters a primary reflux tank;

(4) and the liquid phase in the primary reflux tank flows back to the alcohol ketone drying tower from the feeding stream at the top of the alcohol ketone drying tower.

6. The process of claim 5, wherein: the water content of the crude alcohol ketone discharged from the tower bottom of the alcohol ketone drying tower is less than 100 ppm.

7. The process of claim 5, wherein: and hydrogen is extracted from a gas-phase discharge port of the alcohol ketone drying tail cooler.

8. The process of claim 5, wherein: and (4) completely refluxing the oil phase at the top of the alcohol ketone drying tower.

Technical Field

The invention belongs to the field of organic chemistry, and particularly relates to a process method for quenching and dehydrating cyclohexanol dehydrogenation products.

Background

Cyclohexanone is an important organic chemical raw material. In China, 65% of cyclohexanone is used as a raw material for producing caprolactam, 20% of cyclohexanone is used as a raw material for producing adipic acid, and the rest of cyclohexanone is used as a related chemical raw material. In addition, cyclohexanone is an excellent solvent and can be used as a solvent for nitrocellulose, vinyl chloride polymers and copolymers of paints. With the rapid development of chemical fiber industry in China, the yields of caprolactam and adipic acid are increased year by year, the demand of cyclohexanone is increased day by day, and the development and utilization prospect is wide.

The traditional cyclohexene method cyclohexanone process mainly comprises the main processes of benzene hydrogenation, cyclohexene refining, cyclohexene hydration, cyclohexanol refining, cyclohexanol dehydrogenation, cyclohexanone refining and the like.

As shown in fig. 2, in the conventional process flow, the cyclohexanol dehydrogenation product is first subjected to heat exchange with the feed of the dehydrogenation reactor, after part of the heat is recovered, the cyclohexanol dehydrogenation product is condensed to 50 deg.C by condenser and tail cooler, uncondensed hydrogen is separated, and is pressurized by compressor and sent to downstream device, liquid phase generated by condensation enters dehydrogenation material buffer tank, sending to a drying tower by a feeding pump, condensing the gas phase evaporated from the top of the drying tower, entering a reflux tank of the drying tower, layering in the reflux tank of the drying tower, wherein the upper oil phase returns to the dehydrogenation chatty buffer tank, the lower water phase is sent to sewage treatment, and then cyclohexanone products are obtained through light and heavy removal and other operations, because most of heat of materials is consumed in the transportation process, the energy consumption for preparing cyclohexanone by using the process is high, the production cost is high, and the energy conservation and the environmental protection are not facilitated.

Disclosure of Invention

In view of the above, the present invention aims to provide a process for quenching and dehydrating cyclohexanol dehydrogenation products, wherein the condensation and dehydration steps in the production process of cyclohexanone are combined in an alcohol-ketone drying tower to complete the separation process of quenching and dehydration, low-temperature hydrogen is extracted from the top of the tower, and saturated liquid materials are extracted from the bottom of the tower, so as to save the consumption of circulating water and steam, reduce the energy consumption for producing cyclohexanone, and reduce the production cost of enterprises.

In order to achieve the purpose, the technical scheme of the invention is realized as follows:

a cyclohexanol dehydrogenation product quenching and dehydration equipment comprises an alcohol ketone drying tower, wherein a middle feed inlet of the alcohol ketone drying tower is communicated with a discharge outlet of a cyclohexanol dehydrogenation reactor, a product discharged by the cyclohexanol dehydrogenation reactor forms a gas-liquid mixture after heat exchange, a gas-phase product enters the alcohol ketone drying tower, a liquid-phase product directly flows into the alcohol ketone drying tower, the feeding temperature is 150 ℃, in the alcohol ketone drying tower, hydrogen, light components, cyclohexanone and water are evaporated out at the top of the alcohol ketone drying tower, a liquid phase is concentrated at the bottom of the alcohol ketone drying tower, a reboiler at the bottom of the alcohol ketone drying tower heats the liquid phase of the alcohol ketone drying tower, the top of the alcohol ketone drying tower is condensed to form an oil phase which is totally refluxed, a crude alcohol ketone can be extracted from a tower bottom of the alcohol ketone drying tower, the water content of the crude alcohol ketone is controlled below 100ppm, and finally the crude alcohol ketone is sent to the middle of the lightness removing tower under the driving action of a discharge pump of the alcohol ketone drying tower, carrying out subsequent treatment;

the feeding hole of the alcohol ketone drying condenser is communicated with the gas outlet at the top of the alcohol ketone drying tower, a gas-phase mixture discharged from the top of the alcohol ketone drying tower enters the alcohol ketone drying condenser, part of the gas phase is condensed in the alcohol ketone drying condenser to form a condensate, the rest gas phase flows backwards, and the condensate flows downwards under the action of gravity;

the device comprises a primary reflux tank, a feed inlet of the primary reflux tank is communicated with a liquid phase discharge port of an alcohol ketone drying condenser, condensate condensed in the alcohol ketone drying condenser directly flows into the primary reflux tank under the action of gravity, a discharge port of the primary reflux tank is communicated with a feed inlet at the top of the alcohol ketone drying condenser, all liquid phases collected in the primary reflux tank are returned to the feed inlet at the top of an alcohol ketone drying tower through a reflux pump, and when the liquid phases flow downwards in the alcohol ketone drying tower, heat exchange can be carried out between the liquid phases and an upwards flowing gas phase in the alcohol ketone drying tower, so that the heat utilization rate is improved;

the device comprises an alcohol ketone drying tail cooler, a dehydrogenation compressor, a gas phase discharge port, a liquid phase discharge port, a gas phase discharge port and a gas phase discharge port, wherein the gas phase discharge port is communicated with the gas phase discharge port;

a feed inlet of the secondary reflux tank is communicated with a liquid-phase discharge outlet of the alcohol ketone drying tail cooler, condensate formed by condensation in the alcohol ketone drying tower tail cooler flows into the secondary reflux tank under the action of gravity, and standing in a secondary reflux tank to separate into an oil phase layer at the upper layer and a water phase layer at the lower layer, wherein the oil phase discharge port of the secondary reflux tank is communicated with the feed port of the primary reflux tank, namely, the oil phase substance in the oil phase layer flows into the first-stage reflux tank under the action of gravity, and is mixed with condensate formed by condensation in the alcohol ketone drying condenser, under the action of a reflux pump, the mixture enters the alcohol ketone drying tower through a feed inlet at the top of the alcohol ketone drying tower for circulation, and the water phase substance in the secondary reflux tank is directly discharged from a water phase discharge port at the bottom of the secondary reflux tank and treated as sewage, wherein the content of the organic material in the water phase layer is less than 1%.

Furthermore, a reflux pump is communicated between the primary reflux tank and the alcohol ketone drying tower, and the reflux pump can pump the liquid-phase substances collected in the primary reflux tank into a feed inlet at the top of the alcohol ketone drying tower for cyclic treatment.

Furthermore, a gas-phase discharge port of the alcohol ketone drying tail cooler is communicated with a dehydrogenation compressor, and the dehydrogenation compressor can compress and extract cold air which is discharged by the alcohol ketone drying tail cooler and is not condensed and then send out of a boundary area.

Further, a discharge hole at the bottom of the alcohol ketone drying tower is communicated with a feed inlet of the lightness-removing tower, a discharge pump is arranged between the alcohol ketone drying tower and the lightness-removing tower, and the kettle liquid of the alcohol ketone drying tower finally flows into the middle of the lightness-removing tower under the action of the discharge pump.

The cyclohexanol dehydrogenation product quenching and dewatering process adopts the equipment, and comprises the following steps:

(1) introducing a liquid mixed product discharged from the cyclohexanol dehydrogenation reactor into an alcohol ketone drying tower, wherein the feeding position is the middle part of the alcohol ketone drying tower, a gas-phase substance evaporated from the alcohol ketone drying tower enters an alcohol ketone drying condenser from the top of the alcohol ketone drying tower, and crude alcohol ketone is collected in a tower kettle of the alcohol ketone drying tower to form a kettle liquid which is discharged and then enters a lightness removing tower;

(2) after entering an alcohol ketone drying condenser, a part of gas-phase substances evaporated from the top of the alcohol ketone drying tower is condensed to form condensate after meeting cold, and the condensate directly flows into a primary reflux tank under the action of gravity, while uncondensed gas phase is transported backwards and enters an alcohol ketone drying tail gas cooler;

(3) the uncondensed gas phase discharged by the alcohol ketone drying condenser enters an alcohol ketone drying tail cooler, part of the uncondensed gas phase is condensed after meeting cold to form condensate, and directly enters a secondary reflux tank under the action of gravity, the uncondensed gas phase is transported backwards, wherein the condensate is stood in the secondary reflux tank and is layered into a water layer and an oil layer, the oil layer flows into a primary reflux tank under the action of gravity, the water phase is discharged as sewage, the uncondensed gas phase is mainly hydrogen, and the hydrogen is compressed and purified by a dehydrogenation compressor connected with the alcohol ketone drying tail cooler and then is discharged out of a battery compartment;

(4) and liquid phase mixture collected by the first-stage reflux tank from the alcohol ketone drying condenser and the second-stage reflux tank flows back to the alcohol ketone drying tower from the feeding material at the top of the alcohol ketone drying tower under the action of a reflux pump, and the liquid phase mixture is contacted with the gas phase evaporated from the alcohol ketone drying tower in the ascending process in the process of flowing downwards along the alcohol ketone drying tower, so that the liquid phase mixture is preheated, and the gas phase is precooled, thereby further utilizing the heat.

Further, the water content of the crude alcohol ketone discharged from the tower bottom of the alcohol ketone drying tower is less than 100 ppm.

Further, hydrogen is extracted from a gas-phase discharge port of the alcohol ketone drying tail cooler.

Further, the oil phase at the top of the alcohol ketone drying tower is totally refluxed.

Compared with the prior art, the quenching and dehydration process method for the cyclohexanol dehydrogenation product has the following advantages:

the process method of the invention can save steam consumption of circulating water and a rectification separation unit, reduce energy consumption and production cost, and has wide application prospect.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate an embodiment of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

fig. 1 is a schematic view of a connection structure of a quenching and dehydration apparatus for a cyclohexanol dehydrogenation product according to an embodiment of the present invention;

FIG. 2 is a schematic diagram of a connection structure of a cyclohexanone production apparatus in the prior art.

Description of reference numerals:

1. an alcohol ketone drying tower; 2. an alcohol ketone drying condenser; 3. a first-stage reflux tank; 4. alcohol ketone drying tail cooling device; 5. a secondary reflux tank; 6. a reflux pump; 7. a dehydrogenation compressor.

Detailed Description

Unless defined otherwise, technical terms used in the following examples have the same meanings as commonly understood by one of ordinary skill in the art to which the present invention belongs. The test reagents used in the following examples, unless otherwise specified, are all conventional biochemical reagents; the experimental methods are conventional methods unless otherwise specified.

In order to reduce the energy consumption of the device and reduce the consumption of steam and circulating water, the invention changes the condensation mode of dehydrogenation reaction materials, and sends both gas phase and liquid phase cooled by a feed preheater to an alcohol ketone drying tower to be used as feed, wherein the feed temperature is about 150 ℃, and simultaneously, two processes of condensation and dehydration in the traditional process are combined to be carried out in one alcohol ketone drying tower, thereby completing the separation process of quenching and dehydration. Low-temperature hydrogen is separated from the top of the alcohol ketone drying tower, water contained in the materials is removed, and liquid materials with saturated temperature are extracted from the tower bottom and enter the separation unit, so that the steam consumption of circulating water and the separation unit is saved, the energy consumption is reduced, and the cost is reduced.

The present invention will be described in detail with reference to the following examples and accompanying drawings.

As shown in figure 1, the invention designs a cyclohexanol dehydrogenation product quenching and dewatering device, which comprises an alcohol ketone drying tower 1, an alcohol ketone drying condenser 2, a primary reflux tank 3, an alcohol ketone drying tail cooler 4 and a secondary reflux tank 5,

a middle feed inlet of the alcohol ketone drying tower 1 is communicated with a discharge outlet of a cyclohexanol dehydrogenation reactor, a gas-liquid mixture is formed after heat exchange is carried out on a product discharged from the cyclohexanol dehydrogenation reactor, a gas-phase product enters the alcohol ketone drying tower 1, a liquid-phase product directly flows into the alcohol ketone drying tower 1, the feeding temperature is 150 ℃, in the alcohol ketone drying tower 1, hydrogen, light components, cyclohexanone and water are evaporated out at the top of the alcohol ketone drying tower 1, the liquid phase is concentrated at the bottom of the alcohol ketone drying tower 1, a reboiler at the bottom of the alcohol ketone drying tower 1 heats the liquid phase of the alcohol ketone drying tower 1, the condensation at the top of the tower forms an oil phase which is totally refluxed, crude alcohol ketone can be extracted from a tower bottom of the alcohol ketone drying tower 1, the water content of the crude alcohol ketone is controlled below 100ppm, and finally the crude alcohol ketone is sent to the middle of the light component removal tower for subsequent treatment under the driving action of a discharge pump of the alcohol ketone drying tower 1;

the feed inlet of the alcohol ketone drying condenser 2 is communicated with the gas outlet at the top of the alcohol ketone drying tower 1, a gas-phase mixture discharged from the top of the alcohol ketone drying tower 1 enters the alcohol ketone drying condenser 2, part of the gas phase is condensed in the alcohol ketone drying condenser 2 to form a condensate, the rest gas phase flows backwards, and the condensate flows downwards under the action of gravity;

the feeding hole of the primary reflux tank 3 is communicated with the liquid phase discharging hole of the alcohol ketone drying condenser 2, condensate formed by condensation in the alcohol ketone drying condenser 2 directly flows into the primary reflux tank 3 under the action of gravity, the discharging hole of the primary reflux tank 3 is communicated with the feeding hole at the top of the alcohol ketone drying condenser 2, all the liquid phases collected in the primary reflux tank 3 are returned to the feeding hole at the top of the alcohol ketone drying tower 1 through a reflux pump 6, and when the liquid phases flow downwards in the alcohol ketone drying tower 1, heat exchange is generated between the liquid phases and the gas phase flowing upwards in the alcohol ketone drying tower 1, so that the heat utilization rate is improved;

the feed inlet of the alcohol ketone drying tail cooler 4 is communicated with the gas-phase discharge outlet of the alcohol ketone drying condenser 2, the residual gas phase discharged from the alcohol ketone drying condenser 2 is subjected to secondary condensation in the alcohol ketone drying tail cooler 4, part of the gas phase is condensed to form condensate, the condensate is discharged from the liquid-phase discharge outlet at the bottom of the alcohol ketone drying tail cooler 4, and the residual uncondensed gas phase is discharged backwards from the gas-phase discharge outlet above the alcohol ketone drying tail cooler 4, wherein the main component is hydrogen which is compressed and purified under the action of a dehydrogenation compressor 7 and then is discharged out of a boundary area;

a feed inlet of the secondary reflux tank 5 is communicated with a liquid-phase discharge outlet of the alcohol ketone drying tail cooler 4, condensate formed by condensation in the alcohol ketone drying tower 1 tail cooler flows into the secondary reflux tank 5 under the action of gravity, and is kept stand and layered in a secondary reflux tank 5 into an oil phase layer positioned at the upper layer and a water phase layer positioned at the lower layer, wherein an oil phase discharge hole of the secondary reflux tank 5 is communicated with a feed inlet of a primary reflux tank 3, namely, the oil phase substance in the oil phase layer flows into the first-stage reflux tank 3 under the action of gravity, and is mixed with condensate formed by condensation in the alcohol ketone drying condenser 2, under the action of a reflux pump 6, the mixture enters the alcohol ketone drying tower 1 through a feed inlet at the top of the alcohol ketone drying tower 1 for circulation, and the water phase substance in the secondary reflux tank 5 is directly discharged from a water phase discharge port at the bottom of the secondary reflux tank 5 to be treated as sewage, wherein the content of the organic material in the water phase layer is less than 1%.

Further, a reflux pump 6 is communicated between the first-stage reflux tank 3 and the alcohol ketone drying tower 1, and the reflux pump 6 can pump the liquid-phase substances collected in the first-stage reflux tank 3 into a feed inlet at the top of the alcohol ketone drying tower 1 for cyclic treatment.

Further, a gas-phase discharge port of the alcohol ketone drying tail cooler 4 is communicated with a dehydrogenation compressor 7, and the dehydrogenation compressor 7 can compress and extract the cold air which is discharged from the alcohol ketone drying tail cooler 4 and is not condensed and then send out of a battery limit.

Further, a discharge hole at the bottom of the alcohol ketone drying tower 1 is communicated with a feed inlet of the light component removal tower, a discharge pump is arranged between the alcohol ketone drying tower 1 and the light component removal tower, and the kettle liquid of the alcohol ketone drying tower 1 finally flows into the middle of the light component removal tower under the action of the discharge pump.

Examples

In this embodiment, the product of the cyclohexanol dehydrogenation apparatus is processed by the quenching and dehydration equipment for cyclohexanol dehydrogenation products, and the method specifically includes the following steps:

(1) introducing a liquid mixed product discharged from the cyclohexanol dehydrogenation reactor into an alcohol ketone drying tower, wherein the feeding position is the middle part of the alcohol ketone drying tower, a gas-phase substance evaporated from the alcohol ketone drying tower enters an alcohol ketone drying condenser from the top of the alcohol ketone drying tower, and crude alcohol ketone is collected in a tower kettle of the alcohol ketone drying tower to form a kettle liquid which is discharged and then enters a lightness removing tower;

(2) after entering an alcohol ketone drying condenser, a part of gas-phase substances evaporated from the top of the alcohol ketone drying tower is condensed to form condensate after meeting cold, and the condensate directly flows into a primary reflux tank under the action of gravity, while uncondensed gas phase is transported backwards and enters an alcohol ketone drying tail gas cooler;

(3) the uncondensed gas phase discharged by the alcohol ketone drying condenser enters an alcohol ketone drying tail cooler, part of the uncondensed gas phase is condensed after meeting cold to form condensate, and directly enters a secondary reflux tank under the action of gravity, the uncondensed gas phase is transported backwards, wherein the condensate is stood in the secondary reflux tank and is layered into a water layer and an oil layer, the oil layer flows into a primary reflux tank under the action of gravity, the water phase is discharged as sewage, the uncondensed gas phase is mainly hydrogen, and the hydrogen is compressed and purified by a dehydrogenation compressor connected with the alcohol ketone drying tail cooler and then is discharged out of a battery compartment;

(4) and liquid phase mixture collected by the first-stage reflux tank from the alcohol ketone drying condenser and the second-stage reflux tank flows back to the alcohol ketone drying tower from the feeding material at the top of the alcohol ketone drying tower under the action of a reflux pump, and the liquid phase mixture is contacted with the gas phase evaporated from the alcohol ketone drying tower in the ascending process in the process of flowing downwards along the alcohol ketone drying tower, so that the liquid phase mixture is preheated, and the gas phase is precooled, thereby further utilizing the heat.

Comparative example

The comparative example is based on the existing flow in the field, as shown in fig. 2, a cyclohexanol dehydrogenation product firstly exchanges heat with the feeding material of a dehydrogenation reactor, after partial heat is recovered, all materials are condensed to 50 ℃ through a condenser and a tail cooler, separated hydrogen is pressurized and sent to a downstream device through a compressor, a condensed liquid phase enters a dehydrogenation material buffer tank and is sent to a drying tower through a pump, a gas phase at the top of the drying tower is condensed, an oil phase returns to a dehydrogenation pump tank, a water phase is sent to sewage treatment, and then the cyclohexanone product is obtained through light weight removal, heavy weight removal and other operations.

Calculated by using a 20 ten thousand ton/year cyclohexanone scale device, according to the flow in the comparative example, the heat load of the drying tower kettle is 5522.9kW, and the consumption of medium-pressure steam (the pressure is 1.2MPaG) is 10.04 t/h. By adopting the flow in the embodiment, the heat load of the alcohol ketone drying tower is 784.6kW, the consumed medium-pressure steam amount (the pressure is 1.2MPaG) is 1.43t/h, the steam can be saved by 8.6t/h, the circulating water consumption is reduced, and the energy-saving effect is remarkable.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.