CN107955642B

CN107955642B - Method for mixed hydrogenation of carbon five raffinate oil and coker gasoline

Info

Publication number: CN107955642B
Application number: CN201610896074.7A
Authority: CN
Inventors: 俞坚祥; 谢国群; 林水生; 凌再申; 吴晓敏; 王建军; 吴旭波; 王亚勤
Original assignee: China Petroleum and Chemical Corp
Current assignee: China Petroleum and Chemical Corp
Priority date: 2016-10-14
Filing date: 2016-10-14
Publication date: 2020-07-31
Anticipated expiration: 2036-10-14
Also published as: CN107955642A

Abstract

The invention relates to the field of petroleum processing, in particular to a method for carrying out mixed hydrogenation on carbon five raffinate oil and coker gasoline and a system for carrying out mixed hydrogenation on carbon five raffinate oil and coker gasoline. The method for mixed hydrogenation of carbon five raffinate oil and coker gasoline comprises the following steps: and (3) carrying out pre-hydrogenation reaction on the carbon five raffinate oil to ensure that diolefin in the carbon five raffinate oil is subjected to hydrogenation saturation, and taking a product obtained by the pre-hydrogenation reaction as a diluent to carry out hydrogenation reaction together with the coking gasoline. The method and the system can effectively solve the difficulties that the coking gasoline and the carbon five raffinate oil are easy to coke and polymerize in the hydrogenation process, can reasonably utilize resources, effectively reduce the cost of raw materials and energy loss, and can effectively prolong the operation period of equipment.

Description

Method for mixed hydrogenation of carbon five raffinate oil and coker gasoline

Technical Field

The invention relates to the field of petroleum processing, in particular to a method for carrying out mixed hydrogenation on carbon five raffinate oil and coker gasoline and a system for carrying out mixed hydrogenation on carbon five raffinate oil and coker gasoline.

Background

The coking gasoline contains high-content olefin, and is easy to polymerize and coke under the condition of single hydrogenation, so that the processing difficulty is high.

The ethylene byproduct carbon five raffinate oil is rich in diolefin with high economic value, and is taken as a carbon five comprehensive utilization technology, the carbon five diolefin subdivision has a mature patent technology at present, and is also a hot problem of chemical research, the key point is to separate various useful monomers which are in short supply in the chemical industry, mainly diolefin and isoamylene, and the technology for improving the carbon five comprehensive utilization rate at present is basically adopted. However, the ethylene-carbon five raffinate oil used in the process technology still contains high diolefin, and is easy to polymerize and coke under conventional processing conditions, so that the processing and utilization difficulty is high.

Disclosure of Invention

The invention aims to overcome the defects that the hydrotreating difficulty of the coking gasoline is higher in the prior art and/or the hydrotreating difficulty of the carbon five raffinate oil is higher in the prior art, and provides a method for mixed hydrogenation of the carbon five raffinate oil and the coking gasoline and a system for mixed hydrogenation of the carbon five raffinate oil and the coking gasoline. The method and the system can effectively solve the difficulties that the coking gasoline and the carbon five raffinate oil are easy to coke and polymerize in the hydrogenation process, can reasonably utilize resources, effectively reduce the cost of raw materials and energy loss, and can effectively prolong the operation period of equipment.

In view of the defects that the carbon five raffinate oil and the coking gasoline both have high-concentration olefin, the olefin is easy to polymerize and coke in the hydrogenation reaction, the pressure difference between a reactor and a heat exchanger is easy to rise, and the coking blocks the heat exchanger to cause the shutdown of the device in serious cases, the inventor of the invention finds that the hydrogenation reaction of the carbon five raffinate oil and the hydrogenation reaction of the coking gasoline can be skillfully combined, so that the defects of the carbon five raffinate oil and the coking gasoline can be overcome, and a naphtha product and a light stone product which can be used as ethylene cracking raw materials can be obtained. Specifically, the inventor of the invention finds that diolefins in the carbon five raffinate oil are subjected to hydrogenation saturation while monoolefins are not subjected to hydrogenation reaction and are not subjected to desulfurization and denitrification reaction by performing pre-hydrogenation saturation treatment on the carbon five raffinate oil, and a product obtained by the pre-hydrogenation saturation treatment can be just used as a diluent for the hydrogenation reaction of the coking gasoline, so that the problem of coking of the hydrogenation reaction of the coking gasoline is effectively relieved, and the operation period of a system is effectively prolonged.

The invention provides a method for mixed hydrogenation of carbon five raffinate oil and coker gasoline, wherein the method comprises the following steps: and (3) carrying out pre-hydrogenation reaction on the carbon five raffinate oil to ensure that diolefin in the carbon five raffinate oil is subjected to hydrogenation saturation, and taking a product obtained by the pre-hydrogenation reaction as a diluent to carry out hydrogenation reaction together with the coking gasoline.

The invention provides a system for mixed hydrogenation of carbon five raffinate oil and coker gasoline, wherein the system comprises a carbon five raffinate oil source, a coker gasoline source, a pre-hydrogenation reactor and a hydrogenation reactor, wherein an inlet of the pre-hydrogenation reactor is communicated with the carbon five raffinate oil source, an outlet of the pre-hydrogenation reactor is communicated with an inlet of the hydrogenation reactor, and an inlet of the hydrogenation reactor is also communicated with the coker gasoline source.

Additional features and advantages of the invention will be set forth in the detailed description which follows.

Drawings

The accompanying drawings, which 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 principles of the invention and not to limit the invention. In the drawings:

FIG. 1 is a carbon five raffinate and coker gasoline hybrid hydrogenation system according to one embodiment of the present invention.

Description of the reference numerals

FI401 raw material dehydrator; a P205 pre-hydrogenated feed pump; e271 prehydrogenation heat exchanger; e270 prehydrogenation heater; r200 is a pre-hydrogenation reactor; c202 recycle hydrogen compressor; e201 a first hydrogenation heat exchanger; e202AB second hydrogenation heat exchanger; e202CD third hydrogenation heat exchanger; f201 reaction heating furnace; r201 a first hydrogenation reactor; r202 a second hydrogenation reactor; v243 hot high pressure separator; v244 hot low pressure separator; v202 cold high pressure separator; v203 cold low pressure separator; v206 diluent reservoir; a P204 diluent pump; v201 raw oil buffer tank; a P201 hydrogenation feed pump; a T201 hydrogen sulfide removal stripping tower; t203, a recycle hydrogen desulfurization tower; v204 circulates a hydrogen separation tank.

Detailed Description

The following describes in detail specific embodiments of the present invention. It should be understood that the detailed description and specific examples, while indicating the present invention, are given by way of illustration and explanation only, not limitation.

The endpoints of the ranges and any values disclosed herein are not limited to the precise range or value, and such ranges or values should be understood to encompass values close to those ranges or values. For ranges of values, between the endpoints of each of the ranges and the individual points, and between the individual points may be combined with each other to give one or more new ranges of values, and these ranges of values should be considered as specifically disclosed herein.

In the present invention, the pre-hydrogenation reaction is desirably carried out so as to saturate diolefins in the carbon five raffinate, that is, so that 90 wt% or more of the carbon five raffinate does not undergo a monoolefin hydrogenation reaction, a desulfurization reaction, a denitrification reaction, or other reactions. To achieve this, it is preferable to control the conditions of the prehydrogenation reaction. The inventors of the present invention have found that the above object can be achieved when the temperature of the prehydrogenation reaction is controlled to 150 ℃ or lower and the catalyst is a hydrogenation catalyst containing no heavy metal. The temperature of the pre-hydrogenation reaction can be 100-150 ℃, preferably 100-130 ℃, and more preferably 100-120 ℃; the catalyst used for the pre-hydrogenation reaction can be various hydrogenation catalysts without heavy metals.

In the present invention, the conditions of the prehydrogenation reaction further include: the hydrogen-oil ratio can be 200-500v/v, preferably 200-350 v/v; the space velocity can be 1.2-3.95h^-1Preferably 1.6-3.95h^-1(ii) a The pressure may be 3.5-5MPa, preferably 3.8-5 MPa.

In the present invention, the method further comprises: introducing an additional diluent to carry out a pre-hydrogenation reaction together with the carbon five raffinate oil, wherein the dosage of the additional diluent is not particularly limited, and the weight ratio of the dosage of the carbon five raffinate oil to the dosage of the additional diluent can be 1: 3-15, preferably 1: 5-10, more preferably 1: 6-8. The type of the external diluent is not particularly limited, and a diluent conventionally used in the art may be used, and for example, a non-aromatic gasoline, i.e., a gasoline containing no aromatic hydrocarbon; the source of the external diluent is not particularly limited, and can be obtained by, for example, benzene extraction, aromatic extraction, or the like.

In the present invention, the carbon five raffinate is subjected to the pre-hydrogenation reaction to hydrogenate all or most of the dienes therein, and preferably, the content of the dienes in the feed obtained by pre-hydrogenating the carbon five raffinate is up to 0.4 wt% or less, more preferably up to 0.1 wt% or less.

In the invention, the material obtained after the carbon five raffinate oil is subjected to the pre-hydrogenation treatment can be used as a diluent to carry out hydrogenation reaction together with the coker gasoline, so that the concentration of the dialkene in the coker gasoline is diluted, the coking phenomenon in the hydrogenation reaction process can be effectively relieved, and the hydrogenation reaction can be smoothly operated for a long period. The mixing ratio of the product obtained by the pre-hydrogenation reaction to the coker gasoline can be determined according to the content of diolefins in the coker gasoline and the condition of the hydrogenation reaction, for example, the mixing ratio of the product obtained by the pre-hydrogenation reaction to the coker gasoline can be 1: 1-2.5, preferably 1: 1.5-2.

In the present invention, the amount ratio of the carbon five raffinate, the external diluent and the coker gasoline may be determined according to the above-mentioned amount ratio of the carbon five raffinate to the external diluent and the mixing ratio of the product obtained by the pre-hydrogenation reaction to the coker gasoline, and preferably, the weight ratio of the amounts of the carbon five raffinate, the external diluent and the coker gasoline simultaneously satisfies 1: 3-15: 5-20, preferably 1: 5-10: 8-16, most preferably 1: 6-8: 12-16.

In the present invention, the conditions of the hydrogenation reaction are not particularly limited, and may be hydrogenation conditions conventional in the art, and may include, for example: the hydrogen-oil ratio is 250-600v/v, preferably 350-500 v/v; the space velocity is 0.8-2h^-1Preferably 0.8-1.7h^-1(ii) a The pressure is 3.5-4.5MPa, preferably3.8-4.5 MPa; the temperature is 210 ℃ to 275 ℃, preferably 210 ℃ to 240 ℃.

In the present invention, in order to make full use of materials and energy in the system, preferably, the method further comprises: and carrying out gas-liquid separation on the product obtained by the hydrogenation reaction, and recycling the obtained gas to the pre-hydrogenation reaction and/or the hydrogenation reaction. Usually, H is contained in the gas obtained by the gas-liquid separation₂In an amount of about 80% by weight, which gas can be returned to said pre-hydrogenation reaction and/or to said hydrogenation reaction to provide H₂In addition, H is consumed due to the pre-hydrogenation reaction and the hydrogenation reaction₂Therefore, in addition, it is necessary to supplement pure H₂(generally referred to as fertilizer hydrogen) which may be mixed with the above-mentioned returned gas and then subjected to the preliminary hydrogenation reaction and/or the hydrogenation reaction, or may be separately subjected to the preliminary hydrogenation reaction and/or the hydrogenation reaction.

In the invention, the liquid material obtained by gas-liquid separation of the product obtained by the hydrogenation reaction can be used as a product or a raw material in other processes after or without subsequent treatment. For example, a liquid obtained by subjecting a liquid material obtained by performing gas-liquid separation on a product obtained by the hydrogenation reaction to desulfurization treatment is a naphtha product, the naphtha product can be used as an ethylene cracking raw material, and a light-weight product can be obtained by partially refluxing at the top of the column in the process.

In the present invention, the method for gas-liquid separation of the product obtained by the hydrogenation reaction is not particularly limited, and for example, multistage separation may be performed. According to a specific embodiment of the invention, the product obtained by the hydrogenation reaction is first subjected to a first-stage separation under high temperature and high pressure conditions (temperature of 150-, the liquid obtained by the fourth stage separation and the heavy component obtained by the third stage separation are mixed or respectively (preferably mixed) collected or subjected to hydrogen sulfide removal stripping treatment, and hydrogen sulfide, partial light hydrocarbon and water in the material are removed in the hydrogen sulfide removal stripping treatment process, so that naphtha products and light stone products are obtained. In addition, the gas obtained by the second stage separation, i.e. the gas used for recycling back to the pre-hydrogenation reaction and/or the hydrogenation reaction, can be simply treated before being recycled back for recycling, for example, the gas can be recycled back to the pre-hydrogenation reaction and/or the hydrogenation reaction after being desulfurized, paraffin removed and pressurized.

In the present invention, in order to make more full use of the materials and energy sources in the system, preferably, the method for bringing the materials to the temperature in the pre-hydrogenation reaction and/or the hydrogenation reaction comprises: the material and the material with higher temperature in the system are subjected to heat exchange, for example, the material entering the pre-hydrogenation reactor can be subjected to heat exchange with the material flowing out of the pre-hydrogenation reactor, and the material entering the hydrogenation reactor can be subjected to heat exchange with the material flowing out of the hydrogenation reactor, so that the energy in the system can be fully utilized, and the energy is effectively saved; in the case of insufficient heat being exchanged, additional heating can be carried out.

The second aspect of the present invention provides a system for mixed hydrogenation of carbon five raffinate and coker gasoline, as shown in fig. 1, wherein the system includes a carbon five raffinate source, a coker gasoline source, a pre-hydrogenation reactor R200, and a hydrogenation reactor, an inlet of the pre-hydrogenation reactor R200 is communicated with the carbon five raffinate source, an outlet of the pre-hydrogenation reactor R200 is communicated with an inlet of the hydrogenation reactor, and an inlet of the hydrogenation reactor is also communicated with the coker gasoline source.

In the present invention, in order to make the material reach approximate temperature and pressure before entering the pre-hydrogenation reactor R200, it is preferable that a pressurizing device and a heating device are further disposed on a communicating pipeline between the carbon five raffinate oil source and the pre-hydrogenation reactor R200. Wherein the pressurizing device may be a feed pump, such as pre-hydrogenated feed pump P205 shown in FIG. 1; the heating device may be any device conventionally used in the art for heating a material, but in order to make more full use of the material and energy in the system, preferably, the heating device comprises a pre-hydrogenation heat exchanger E271 and a pre-hydrogenation heater E270, wherein the outlet of the pre-hydrogenation reactor R200 is also communicated with the pre-hydrogenation heat exchanger E271, so that the raw material of the carbon five raffinate oil exchanges heat with the material at the outlet of the pre-hydrogenation reactor in the pre-hydrogenation heat exchanger E271, and the pre-hydrogenation heater E270 may be further arranged for continuously heating the carbon five raffinate oil to a predetermined temperature because the temperature reached by the heat exchange of the carbon five raffinate oil in the pre-hydrogenation heat exchanger E271 is not high enough.

In the invention, the system also comprises an additional diluent source which is communicated with the pre-hydrogenation reactor and is used for diluting the carbon five raffinate oil and carrying out pre-hydrogenation reaction together. The transport pipeline with the added diluent can be combined with a transport pipeline of the carbon five raffinate oil at any position, and preferably is combined with the transport pipeline of the carbon five raffinate oil before a pressurizing device and a hydrogenation device; for example, the line connecting the external diluent source is connected to the line at the inlet of the pre-hydrogenation feed pump P205. The diluent source may also be in communication with a coker gasoline conduit for temporarily supplying diluent to coker gasoline when problems arise with the pre-hydrogenation of carbon five raffinate, or for replenishing a portion of the diluent when insufficient diluent is available to the pre-hydrogenation system. The diluent supply circuit may also include other conventional auxiliary equipment such as a diluent reservoir V206 and a diluent pump P204.

In the present invention, the hydrogenation reactor may be one or more of R201 and R202 shown in fig. 1 in series or parallel. In order to enable the material to reach approximate temperature and pressure before entering the hydrogenation reactor, preferably, a heat exchange unit is further disposed on a communicating pipeline between the coker gasoline source and the hydrogenation reactor, the heat exchange unit includes one or more hydrogenation heat exchangers, such as E201, E202AB, and E202CD shown in fig. 1, an inlet and an outlet of the hydrogenation reactor are both communicated with the heat exchange unit, so that the material entering the hydrogenation reactor and the material flowing out of the hydrogenation reactor exchange heat in the heat exchange unit. As shown in fig. 1, the material entering the hydrogenation reactor sequentially flows through hydrogenation heat exchangers E202CD, E202AB and E201, and the material flowing out of the hydrogenation reactor sequentially flows through hydrogenation heat exchangers E201, E202AB and E202CD, so that the material entering the hydrogenation reactor and the material flowing out of the hydrogenation reactor exchange heat in the hydrogenation heat exchangers E201, E202AB and E202CD, and thus the temperature of the material entering the hydrogenation reactor gradually increases and the temperature of the material flowing out of the hydrogenation reactor gradually decreases. The number of hydrogenation heat exchangers can be determined according to the temperature to be reached and the temperature of the feed, and the number is enough to make the feed reach the required temperature.

In the present invention, preferably, an outlet of the pre-hydrogenation reactor R200 is sequentially communicated with the heat exchange unit and the hydrogenation reactor, that is, the material flowing out of the pre-hydrogenation reactor R200 enters the heat exchange unit, and is mixed with the coker gasoline in the heat exchange unit to function as a diluent, and the obtained mixture enters the hydrogenation reactor together. Since the material exiting the pre-hydrogenation reactor R200 is already at a certain temperature, it can be fed to a hydrogenation heat exchanger located in the middle of the plurality of hydrogenation heat exchangers, and as an example in fig. 1, the material exiting the pre-hydrogenation reactor R200 can enter the middle second hydrogenation heat exchanger E202AB, and be mixed with coker gasoline in the second hydrogenation heat exchanger E202 AB.

In the invention, the material flowing out of the hydrogenation reactor can be subjected to gas-liquid separation, the gas obtained by separation is recycled to the pre-hydrogenation reactor R200 and/or the hydrogenation reactors R201 and R201, and the liquid obtained by separation is used as a product after no treatment or simple treatment. The gas-liquid separation process can use equipment conventional in the art, according to a preferred embodiment of the invention, the outlet of the hydrogenation reactor is connected with the inlet of a hot high-pressure separator V243, the light component outlet of the hot high-pressure separator V243 is connected with the inlet of a cold high-pressure separator V202, the heavy component outlet of the hot high-pressure separator V243 is connected with the inlet of a hot low-pressure separator V244, the heavy component outlet of the cold high-pressure separator V202 and the light component outlet of the hot low-pressure separator V244 are both connected with the inlet of a cold low-pressure separator V203, the heavy component outlet of the cold low-pressure separator V203 and the heavy component outlet of the hot low-pressure separator V244 are both connected with the inlet of a hydrogen sulfide stripping tower T201, and therefore, the separated liquid is collected after passing through the hydrogen sulfide stripping tower T201; in addition, the light weight fraction outlet of the cold high-pressure separator V202 is communicated with the inlet of the pre-hydrogenation reactor R200 and/or the inlet of the hydrogenation reactor, thereby realizing the circulation of the separated gas back to the pre-hydrogenation reactor R200 and/or the hydrogenation reactors R201 and R201. Preferably, the separated gas is subjected to certain treatment, such as pressurization, desulfurization, paraffin removal and the like, before being recycled to the pre-hydrogenation reactor R200 and/or the hydrogenation reactors R201 and R201, and according to a preferred embodiment of the present invention, a recycle hydrogen desulfurization tower T203, a recycle hydrogen knockout drum V204 and a recycle hydrogen compressor C202 are further sequentially arranged between the light component outlet of the cold high-pressure separator V202 and the inlet of the pre-hydrogenation reactor R200 and/or the inlet of the hydrogenation reactor in the material flow direction.

In addition, H is consumed due to the pre-hydrogenation reaction and the hydrogenation reaction₂Therefore, in addition, it is necessary to supplement pure H₂(generally referred to as fertilizer hydrogen) which may be mixed with the above-mentioned returned gas and then subjected to the preliminary hydrogenation reaction and/or the hydrogenation reaction, or may be separately subjected to the preliminary hydrogenation reaction and/or the hydrogenation reaction. According to a preferred embodiment of the present invention, an inlet of a pure hydrogen pipeline is further disposed between the light component outlet of the cold high-pressure separator V202 and the inlet of the pre-hydrogenation reactor R200 and/or the inlet of the hydrogenation reactor, so that the pure hydrogen and the light component obtained by the cold high-pressure separator V202 are mixed and then enter the pre-hydrogenation reactor R200 and/or the hydrogenation reactor.

In the present invention, the pipeline connecting mode for circulating the separated gas and/or chemical fertilizer hydrogen back to the pre-hydrogenation reactor and/or the hydrogenation reactor is not particularly limited, for example, the gas and/or chemical fertilizer hydrogen can be introduced from a plurality of parts of the pre-hydrogenation reactor and/or the hydrogenation reactor at the same time, and the liquid material can be introduced into the pipeline of the pre-hydrogenation reactor and/or the hydrogenation reactor separately.

In the present invention, the system for mixed hydrogenation of carbon five raffinate and coker gasoline may further comprise other additional equipment conventionally used in the art, for example, a raw material dehydrator may be arranged after the carbon five raffinate source and/or the coker gasoline source to remove water in the material, such as FI401 in fig. 1; for example, a reaction heating furnace, such as F201 in fig. 1, may be disposed between the heat exchange unit and the hydrogenation reactor, and the furnace is used when the system starts to operate and finishes to operate, the heating furnace is not started during the operation of the system, and the material only flows through the heating furnace.

According to a preferred embodiment of the present invention, as shown in fig. 1, the system for the mixed hydrogenation of carbon five raffinate oil and coker gasoline and the method for the mixed hydrogenation of carbon five raffinate oil and coker gasoline using the system of the present invention comprise:

as shown in figure 1, the carbon five raffinate oil from the carbon five raffinate oil source is dehydrated in a raw material dehydrator FI401 along a material pipeline, then is mixed with an external diluent from a diluent storage tank V206 (the mixing weight ratio is 1: 3-15), the mixed material is continuously pressurized to 5-6MPa along the material pipeline in a pre-hydrogenation feeding pump P205, is heated to 100-^-1The pressure is 3.5-5.0MPa, the temperature is 100-: 1-2.5), the mixed material flows through a reaction heating furnace F2 through a first hydrogenation heat exchanger E20101 enter a first hydrogenation reactor R201 and a second hydrogenation reactor R202 for hydrogenation reaction (the reaction conditions comprise a hydrogen-oil ratio of 250-^-1The pressure is 3.5-4.5MPa, the temperature is 210-275 ℃), the materials obtained after the reaction sequentially flow through a first hydrogenation heat exchanger E201, a second hydrogenation heat exchanger E202AB and a third hydrogenation heat exchanger E202CD to heat the materials entering a hydrogenation reactor, then the materials enter a hot high-pressure separator V243 to carry out first-stage separation under the conditions of high temperature and high pressure (the temperature is 150-175 ℃, and the pressure is 3.2-3.8MPa), the light components obtained by the first-stage separation are introduced into a cold high-pressure separator V202 to carry out second-stage separation under the conditions of low temperature and high pressure (the temperature is 35-40 ℃, and the pressure is 3.3-3.5MPa), the heavy components obtained by the first-stage separation are introduced into a hot low-pressure separator V244 to carry out third-stage separation under the conditions of high temperature and low pressure (the temperature is 175 ℃, and the pressure is 0.9-1.1MPa), the liquid obtained by the third-stage separation is introduced into a cold low-pressure separator V203 to carry out the low-temperature and low-pressure separation The temperature is 35-45 ℃, the pressure is 0.9-1.1MPa), the fourth stage separation is carried out, the liquid obtained by the fourth stage separation and the heavy component obtained by the third stage separation are mixed or respectively (preferably mixed) introduced into a hydrogen sulfide removal stripping tower T201 for hydrogen sulfide removal stripping treatment, and a refined naphtha product and a light stone product are obtained; in addition, the gas obtained by the second-stage separation is sequentially circulated in a hydrogen desulfurization tower T203 for desulfurization, is subjected to paraffin removal in a circulating hydrogen separating tank V204, is pressurized to 4-7MPa by a circulating hydrogen compressor C202, is mixed with fertilizer hydrogen (pure hydrogen) with the pressure of 4-7MPa from the outside, and is circulated to the hydrogenation reactors R201 and R202, the pre-hydrogenation reactor R200 and the pipeline of the pre-hydrogenation reactor R200. Therefore, the system and the mode of the invention can realize the hydrotreatment of the carbon five raffinate oil and the coking gasoline, solve the problem of easy coking in the prior art, reasonably utilize resources, effectively reduce the cost of raw materials and energy loss, and effectively prolong the operation period of equipment.

The present invention will be described in detail below by way of examples.

Examples 1-6 and comparative examples 1-2 are provided to illustrate the system for the hybrid hydrogenation of carbon five raffinate and coker gasoline of the present invention and the process for the hybrid hydrogenation of carbon five raffinate and coker gasoline using the same.

In the following comparative examples and examples, the composition and content of carbon five raffinate oil used are shown in table 1, and the composition and content of coker gasoline are shown in table 2.

TABLE 1

TABLE 2

TABLE 3

Density (20 ℃ C.)/g.cm^-3	0.67
		Distillation range/. degree.C
IBP	69
		10％	76
50％	84
		90％	103
EBP	137
		Bromine number/gBr (100g)^-1	24
Sulfur/. mu. g.g^-1	0.5
		Nitrogen/. mu.g.g	<0.5

Example 1

As shown in FIG. 1, the carbon five raffinate (1 part by weight) from the carbon five raffinate source was dehydrated in a raw material dehydrator FI401 along the feed line, and then mixed with an additional diluent (7 parts by weight, obtained by direct supply through an upstream aromatics extraction apparatus, and having the composition shown in Table 3, and the additional diluent used below is the same as that of the present example) from a diluent storage tank V206, and the mixed feed was continuously pressurized to 6.0MPa in a pre-hydrogenation feed pump P205, heated to 120 ℃ in a pre-hydrogenation heat exchanger E271 and a pre-hydrogenation heater E270 along the feed line, and then subjected to a pre-hydrogenation reaction in a pre-hydrogenation reactor R200 to saturate diolefins in the carbon five raffinate (the reaction conditions include a hydrogen-oil ratio of 250V/V and a space velocity of 3.0 h)^-1The pressure is 4.5MPa and the temperature is 145 ℃; using a catalyst without heavy metals, the manufacturer is a medium petrochemical compliant catalyst division company, the mark is FHUDS-6/FH-40C), the material obtained after the pre-hydrogenation reaction firstly flows through a pre-hydrogenation heat exchanger E271 along a pipeline so as to heat the carbon five raffinate oil entering a pre-hydrogenation reactor by using the heat of the material, and then flows into a second hydrogenation heat exchanger E202AB in a heat exchange unit, and the carbon five raffinate oil comes from a coking gasoline source and is already mixed with the carbon five raffinate oil in the second hydrogenation heat exchanger E202ABThe coking gasoline (12 parts by weight) passing through a raw oil buffer tank V201, a hydrogenation raw material pump P201 and a third hydrogenation heat exchanger E202CD is mixed, the mixed material passes through a first hydrogenation heat exchanger E201, flows through a reaction heating furnace F201, enters hydrogenation reactors R201 and R202 for hydrogenation reaction (the reaction conditions comprise that the hydrogen-oil ratio is 400V/V, and the space velocity is 1.6 h)^-1The pressure is 4.5MPa, the temperature is 230 ℃), the materials obtained after the reaction sequentially flow through a first hydrogenation heat exchanger E201, a second hydrogenation heat exchanger E202AB and a third hydrogenation heat exchanger E202CD to heat the materials entering a hydrogenation reactor, then enter a hot high-pressure separator V243 to carry out first-stage separation under the conditions of high temperature and high pressure (the temperature is 160 ℃ and the pressure is 3.6MPa), the light components obtained by the first-stage separation are introduced into a cold high-pressure separator V202 to carry out second-stage separation under the conditions of low temperature and high pressure (the temperature is 40 ℃ and the pressure is 3.4MPa), the heavy components obtained by the first-stage separation are introduced into a hot low-pressure separator V244 to carry out third-stage separation under the conditions of high temperature and low pressure (the temperature is 160 ℃ and the pressure is 1.1MPa), the light components obtained by the third-stage separation and the liquid obtained by the second-stage separation are introduced into a cold low-pressure separator V203 to carry out low, pressure of 1.1MPa) to carry out fourth-stage separation, mixing the liquid obtained by the fourth-stage separation with the heavy component obtained by the third-stage separation or respectively (preferably mixing) introducing the liquid and the heavy component into a hydrogen sulfide removal stripping tower T201 to carry out hydrogen sulfide removal stripping treatment, and obtaining a refined naphtha product (marked as I1) and a light stone product; in addition, the gas obtained by the second-stage separation is sequentially circulated in a hydrogen desulfurization tower T203 for desulfurization, is subjected to paraffin removal in a circulating hydrogen separating tank V204, is pressurized to 5.0MPa by a circulating hydrogen compressor C202, is mixed with chemical fertilizer hydrogen (pure hydrogen) with the pressure of 7.0MPa from the outside, and is circulated to the hydrogenation reactors R201 and R202, the pre-hydrogenation reactor R200 and the pipeline of the pre-hydrogenation reactor R200. Therefore, the system and the mode of the invention can realize the hydrotreatment of the carbon five raffinate oil and the coking gasoline, solve the problem of easy coking in the prior art, reasonably utilize resources, effectively reduce the cost of raw materials and energy loss, and effectively prolong the operation period of equipment.

Example 2

The process and system of example 1 are followed except that the prehydrogenation reaction conditions in the prehydrogenation reactor R200 include: the hydrogen-oil ratio is 200v/v, and the space velocity is 1.6h^-1The pressure is 3.8MPa and the temperature is 100 ℃; the weight ratio of the carbon five raffinate oil to the diluent to the coking gasoline is 1: 6: 12. the resulting naphtha product was designated as I2.

Example 3

The process and system of example 1 are followed except that the prehydrogenation reaction conditions in the prehydrogenation reactor R200 include: the hydrogen-oil ratio is 350v/v, and the space velocity is 3.95h^-1The pressure is 5.0MPa, and the temperature is 130 ℃; the weight ratio of the carbon five raffinate oil to the diluent to the coking gasoline is 1: 8: 16. the resulting naphtha product was designated as I3.

Example 4

The process and system of example 1 are followed except that the prehydrogenation reaction conditions in the prehydrogenation reactor R200 include: the hydrogen-oil ratio is 400v/v, and the space velocity is 1.5h^-1The pressure is 3.7MPa and the temperature is 135 ℃. The resulting naphtha product was designated as I4.

Example 5

The process and system of example 1 were followed except that the carbon five raffinate, external diluent and coker gasoline were used in a weight ratio of 1: 7: 20. the resulting naphtha product was designated as I5.

Example 6

The procedure was followed as in example 1 except that the catalyst used for the prehydrogenation reaction was a heavy metal catalyst containing 0.258 wt% Pd and was manufactured by Zhongpetrochemical Furan catalyst division under the designation SHP-01. The resulting naphtha product was designated as I6.

Comparative example 1

The procedure of example 1 was followed except that the step of the pre-hydrogenation reaction was not performed, and the coker gasoline of 12 parts by weight was directly subjected to the hydrogenation reaction with the diluent of 8 parts by weight without introducing the carbon five raffinate, that is, the route of fig. 1 in which the carbon five raffinate source, the raw material dehydration column FI401, the pre-hydrogenation feed pump P205, the pre-hydrogenation heat exchanger E271, the pre-hydrogenation heater E270 and the pre-hydrogenation reactor R200 were disposed was removed. The resulting naphtha product was designated as D1.

Comparative example 2

The procedure was followed as in comparative example 1 except that 2.5 parts by weight of carbon five raffinate was hydrogenated with 17.5 parts by weight of additional diluent without introducing coker gasoline. The resulting naphtha product was designated as D2.

Test example

The following tests were carried out for examples 1 to 6 and comparative examples 1 to 2, respectively, and the results are shown in Table 4.

(1) The diene contents (m/m) of the feeds obtained at the outlet of the prehydrogenation reactors of examples 1 to 6 were determined according to the methods defined in GZH L H-T4.102.23.336, respectively, and this test was not carried out since comparative examples 1 and 2 had no course of the prehydrogenation reaction;

(2) the sulfur contents (mg/kg) of the obtained naphtha products I1-I6 and D1-D2 were measured respectively according to the method specified in SH-T0253;

(3) bromine numbers (gBr/100g) of the obtained naphtha products I1 to I6 and D1 to D2 were measured respectively according to the method specified in SH-T0236;

(4) the data of the inlet-outlet differential pressure indicating instruments (i.e., the pressure difference at the outlet and the inlet) of the E201, E202AB and E202CD of examples 1-6 and comparative examples 1-2, respectively, were read, i.e., as their respective shell-side differential pressures.

TABLE 4

As can be seen from Table 4, the diolefin content of the prehydrogenation feed obtained by the method of the present invention can reach below 1 wt%, and in combination with other detection parameters, the pretreatment process of the present invention can obtain a better naphtha product and reduce coking. The sulfur content of the naphtha product obtained by the method and the system can reach below 20mg/kg and even below 15mg/kg, and the bromine number can reach below 0.08 wt% and even below 0.06 wt%, so that the naphtha product obtained by the method has high purity; the shell side pressure difference of the E201 can reach below 7kPa and even below 4kPa, the shell side pressure difference of the E202AB can reach below 30kPa and even below 25kPa, and the shell side pressure difference of the E202CD can reach below 40kPa and even below 35kPa, so that the shell side pressure difference of the invention is small, and the coking amount in the system is proved to be small, and the system can realize a longer operation period (the operation period of the invention can reach above 1500 days). While the sulfur content of the naphtha product obtained in the comparative example 1 reaches 50mg/kg, the bromine number reaches 2.0 wt%, and the shell-side pressure difference is far higher than that of the invention, which proves that the coking condition is far worse than that of the invention, so the operation period is far shorter than that of the invention (generally about 700 days). In contrast, in comparative example 2, when a large amount of diluent is used, the bromine number content is still as high as 1.0 wt%, and the shell-side pressure difference is still high, so that the method needs more diluent under the same conditions (temperature and pressure) and is higher in cost, and the hydrogenation effect and the coking control effect are not ideal.

In addition, through accounting according to the energy-saving detection center of Ningbo theory of Industrial science of Zhejiang university, compared with comparative example 1, the energy-saving amount of the embodiment 1 of the invention reaches 130.97 tons of standard coal, so that the invention can reasonably utilize resources and effectively reduce the cost of raw materials and energy loss.

The preferred embodiments of the present invention have been described in detail, however, the present invention is not limited to the specific details of the above embodiments, and various simple modifications may be made to the technical solution of the present invention within the technical idea of the present invention, and these simple modifications are within the protective scope of the present invention. It should be noted that the various technical features described in the above embodiments can be combined in any suitable manner without contradiction, and the invention is not described in any way for the possible combinations in order to avoid unnecessary repetition. In addition, any combination of the various embodiments of the present invention is also possible, and the same should be considered as the disclosure of the present invention as long as it does not depart from the spirit of the present invention.

Claims

1. A method for mixed hydrogenation of carbon five raffinate oil and coker gasoline is characterized by comprising the following steps: pre-hydrogenation reaction is carried out on the carbon five raffinate oil to ensure that dialkene in the carbon five raffinate oil is subjected to hydrogenation saturation, and a product obtained by the pre-hydrogenation reaction is used as a diluent to carry out hydrogenation reaction together with the coking gasoline, wherein the temperature of the pre-hydrogenation reaction is 100-150 ℃, the hydrogen-oil ratio is 200-500v/v, and the airspeed is 1.2-3.95h^-1The pressure is 3.5-5MPa, the catalyst is a hydrogenation catalyst without heavy metal, and the mixing ratio of the product obtained by the pre-hydrogenation reaction to the coking gasoline is 1: 1-2.5.

2. The process of claim 1, wherein the pre-hydrogenation reaction is such that diolefins in the carbon five raffinate are hydrosaturated and 90 wt% or more of the carbon five raffinate is free of mono-olefin hydrogenation, desulfurization, or denitrification.

3. The method according to claim 1 or 2, wherein the method further comprises: introducing an additional diluent to carry out a pre-hydrogenation reaction together with the carbon five raffinate oil, wherein the weight ratio of the carbon five raffinate oil to the additional diluent is 1: 3-15.

4. The process of claim 1 or 2, wherein the mixing ratio of the product obtained from the pre-hydrogenation reaction to coker gasoline is 1: 1.5-2.

5. The process of claim 1, wherein the conditions of the hydrogenation reaction comprise: the hydrogen-oil ratio is 250-600v/v, and the space velocity is 0.8-2h^-1The pressure is 3.5-4.5MPa, and the temperature is 210-275 ℃.

6. The method according to claim 1 or 2, wherein the method further comprises: and carrying out gas-liquid separation on the product obtained by the hydrogenation reaction, and recycling the obtained gas to the pre-hydrogenation reaction and/or the hydrogenation reaction.