Catalytic distillation and hydrogenation of heavy unsaturated products in the system for producing olefins (options)

 

Usage: petrochemistry. The inventive installation olefin production, which is designed for the acquisition and allocation of ethylene and propylene, carry out the hydrogenation With2-acetylenes,3-acetylenes and dienes and C4- and heavier acetylenes, dienes and olefins and selective separation of the products is carried out with application of one or more reactive distillation columns of different designs. These columns contain a hydrogenation catalyst in the processing sections and the sections of the Stripping of light fractions, and simultaneously carry out the reaction of catalytic hydrogenation and distillation. The technical result - the simplification of the process. 2 C. and 13 C.p. f-crystals, 10 ill.

The invention relates to a process for obtaining olefins, in particular to the processing of the input gaseous raw materials for more efficient allocation of product and process by-products: namely, catalytic distillation and hydrogenation of heavy unsaturated products in the system for producing olefins.

Ethylene, propylene and other valuable petrochemical products are obtained by thermal cracking of a variety thermal cracking of these inputs to a variety of products ranging from hydrogen to pyrolysis liquid fuels. The exhaust from the stage of cracking thread, usually called the input gas or the cracking gas, consists of materials this range, then you must separate (fractionate) for different products and by-products with the subsequent reaction (hydrogenation) with the participation of at least some unsaturated by-products.

The typical flow of the input gas includes, in addition to the target product, i.e., ethylene and propylene, With2-acetylene,3-acetylene and diene, and C4and more high acetylene, dieny and olefins, as well as a significant amount of hydrogen. In accordance with the most well-known methods With3-acetylene and C2-acetylene and diene and5and more high dieny, acetylene and olefins is subjected to catalytic hydrogenation in the reactor with a fixed bed using a number of commercially available catalysts. Constantly expanding the scope of catalytic hydrogenation in the reactor with fixed bed covers With4-acetylene, dieny and olefins. These separate stage hydrogenation is carried out in one of the two process sequences. When implementing tipichnogo). Then it is gradually cooled, condensing2and heavier components. From the stream by cryogenic produce hydrogen and fractionation emit methane. Flow with the rest With the2and heavier components are directed to a series of distillation columns. In the first column - ethnoastronomy get the upper shoulder strap, including2-acetylene, olefins and paraffins. This material is sent to a vapor-phase reactor with a fixed bed, in which2-acetylene selectively hydrogenized using hydrogen, the previously selected cryogenic path of flow of the input gas.

In the second column of this sequence - propanethiol get the upper shoulder strap, including3-acetylene, dieny, olefins and paraffins. This material is sent to a vapor - or liquid-phase reactor with a fixed bed, in which3-acetylene and diene selectively hydrogenized using hydrogen, the previously selected cryogenic path of flow of the input gas.

In the third column - butanethiol get the upper shoulder strap, including4-acetylene, dieny, olefins and paraffins. Further, this material is directed to either end of such a series of columns in the quality of the final product or in the liquid-phase reactor with namodugo gas, dieny, acetylene, and in some cases, and olefins.

Distillation residues third columns include5and heavier dieny, acetylene, olefins and paraffins. This material is sent to the number of two liquid-phase reactor with a fixed bed. The first of these catalytically hydrogenized acetylene and diene. Olefins catalytically hydrogenized in the second reactor. In both reactors use hydrogen, previously allocated cryogenic path of flow of the input gas. In some cases, in this third column receive the upper shoulder strap, including as4- and5-acetylene, dieny, olefins and paraffins. Their hydrogenized the same as described above only for C4components in a single liquid-phase reactor with a fixed bed. With6and heavier dieny, acetylene, olefins and paraffins away in the form of bottoms of the third column and hydrogenized as described above, in the two-liquid-phase reactor with a fixed bed.

In one embodiment of this is described directly above the typical way the cracking gas is compressed to an absolute pressure within 2,07-3,45 MPa (300 to 500 pounds per square inch) and sent to distillation column. Upper wrap this column constitute the second layer, which2-acetylene and3-acetylenes and dienes hydrogenized using a small portion of hydrogen contained in the stream With a3and lighter products. Dehydrogenation part C3-acetylenes and dienes, as well as4and heavier acetylenes, dienes and olefins, hydrogenized according to the method similar to that described above. Many new units for production of olefins BUTADIENES hydrogenized to olefins or BUTADIENES and butenes fully hydrogenized to butane. In some cases the cracking furnace return saturated With4components, and sometimes saturated With5components.

Despite widespread, typical methods described above have several disadvantages. When hydrogenized unsaturated With3components (methylacetylene and PROPADIENE)4components and gasoline fraction (including C5components), you need at least three separate reactor with a fixed bed. If the gasoline fraction hydrogenized in two stages, the number of reactors fixed bed is four. The costs of such number of reactors with a fixed layer constitute a significant proportion of the capital cost of the system as a whole and complicate its work. ub>components separately and5-the ingredients together with a gasoline fraction, and in which you want one distillation column is less than the number of hydrogenation reactors remains the same.

The present invention relates to the separation of ethylene and propylene in the olefin production, as well as hydrogenation and separation more high molecular weight unsaturated products. The present invention is to develop a method of selective hydrogenation With2-acetylenes and C3-acetylenes and dienes with additional amounts of ethylene and propylene and hydrogenation With4and heavier acetylenes, dienes and olefins to alkanes without hydrogenation of ethylene and propylene and selective separation of the products obtained according to the technological scheme, which minimized the required number of reactors and distillation columns and, therefore, minimized capital costs and maintenance costs. In particular, the invention provides the use of a new layout combined reactive distillation stages, known as catalytic distillation, for simultaneously conducting reactions of hydrogenation and target separation.

2components, including ethylene, C2components, including propylene, acetylene and diene,4- and5components, including acetylene, dieny and olefins, and C6- and heavier components, including unsaturated compounds, for separation of ethylene and propylene and hydrogenation of C3-acetylenes and dienes with additional quantities of propylene hydrogenation of at least a certain number With4- and5-acetylenes, dienes and olefins to saturated compounds and hydrogenation With6and more high molecular weight unsaturated compounds to a mixture of olefins and saturated compounds without significant hydrogenation of ethylene and propylene, comprising the following stages: A. the release of hydrogen and C2components b. the allocation of ethylene as a product selected from C2components, century introduction of material with3- and heavier components and a quantity of hydrogen in the area of input material reactive distillation column comprising a processing section over the area of input material and the section of the Stripping of light fractions under the area of input material, with at least Obogatitelniy unsaturated components in the form of bottoms, D. introduction C6and more high-molecular unsaturated components in the form of bottoms in contact with hydrogen and a hydrogenation catalyst, as a result of these6and more high-molecular unsaturated components hydrogensource to C6- and heavier olefins and saturated compounds, that is, the Stripping3- With4- and5components with simultaneous introduction of these C3- C4and C5components in contact with the hydrogenation catalyst in the processing zone with getting the top of the shoulder strap and keep in dressing area conditions, including the concentration of hydrogen generated by the mentioned amount of the hydrogen, resulting in3-acetylene and diene hydrogensource with the formation of additional quantities of propylene and consequently at least partially hydrogenized4- and5-acetylene, dieny and olefins, J. separation and isolation from the top of the shoulder strap as a product of propylene and further hydrogenation is contained in the upper chase at least partially hydrogenating4- and5-acetylenes, dienes and olefins with getting saturated With4- and5connections.

< the heavy cracking gasoline, where before stage (a) allocation of C2components of recerving source material emit at least part of this heavy cracking gasoline and which additionally includes the stage of filing a dedicated heavy cracking gasoline with C3- and heavier components and hydrogen in the reactive distillation column.

Preferably graciously gaseous source material was obtained at the stage of cracking of the hydrocarbon starting material, in which C3- and heavier components further include propane and which referred to the stage of distillation of the material with3- and heavier components include phase separation of propane and saturated With4- and5components and return the selected propane and saturated With4and C5components on the stage of cracking.

The preferred method, in which stage (g) allocation of propylene from top of shoulder strap includes the following stages: (I) the introduction of the upper shoulder strap in the area of input material, the second reactive distillation column comprising a processing section over the area of input material and the section of the Stripping of light fractions below the introduction of hydrogen into the second reactive distillation column at a point below the catalyst for hydrogenation,
(III) the distillation of propylene top of a shoulder strap and hydrogenation of C3-C4and C5components.

Preferred the way in which stage (g) allocation of propylene from top of shoulder strap includes the following stages:
(I) the introduction of the upper shoulder strap in the area of input material, the second reactive distillation column comprising a processing section over the area of input material and the section of the Stripping of light fractions below the zone input source material, the Stripping section of light fractions which contains a hydrogenation catalyst,
(II) the introduction of hydrogen into the second reactive distillation column at a point below the catalyst for hydrogenation,
(III) the introduction of material with C3- and heavier components in a number of reactive distillation columns comprising at least one reactive distillation processing section containing a hydrogenation catalyst, and at least one reactive rectifying section Stripping light fractions containing hydrogenation catalyst,
(IV) the introduction of hydrogen in the reactive distillation processing section and the Stripping of light fractions,
(V) the hydrogenation of at least one3 (VI) at least partial hydrogenation of C4- and5-acetylenes, dienes and olefins to saturated compounds in one of the reactive distillation sections,
(VII) the distillation of propylene as the product of C4and C5components
(VIII) the hydrogenation of C6and more high-molecular unsaturated components in one of the reactive distillation sections bog light fractions.

The above objective is also achieved by the creation of a method of processing recerving gaseous source material containing unsaturated With3components, including propylene, acetylene and diene, unsaturated C4and C5components, including acetylene, dieny and olefins, with the aim of hydrogenation With3-acetylenes and dienes and hydrogenation of at least one unsaturated C4and unsaturated With5components without hydrogenation of propylene by selective hydrogenation With3-acetylenes and dienes in the first layer of catalytic distillation in the first catalytic distillation and thereby gain additional propylene, distillation, these propylene and an additional amount of propylene in the form of the top ring and get the Mat is ore of one of the unsaturated With4components and unsaturated With5components in the second layer of catalytic distillation in the second catalytic distillation.

On the appended drawings shows:
in Fig.1 is a diagram of a known plant for producing olefins,
in Fig. 2 is a diagram of a modified well-known plant for producing olefins,
in Fig.3 is a diagram of a plant for producing olefins in accordance with the present invention,
in Fig. 4 is a diagram similar to those shown in Fig.3 and illustrating another embodiment of the present invention,
in Fig. 5 and 6 variant with a different placement of columns for catalytic distillation, shown in Fig.4,
in Fig.7-10 scheme, similar to the schemes in Fig.3 and 4, but illustrating other embodiments of the present invention.

As shown primarily in Fig.1, which shows well-known in the art device for producing olefins in a typical pyrolysis and related installations for heat recovery, the overall position 4, receive input gas 6 flow 8 heavy products, which includes mainly the C8- and heavier components. This injected gas 6 is first compressed in the device 12 to aboriginal processing for separating hydrogen 15, followed by the separation of methane in the device 16. A small part3and heavier material, which is condensed in the compressor unit, often referred bypassing stages cryogenic demethanization and directly and in the form of a stream 31 is fed directly to propanethiol column 30. Then, in the device 20 of the gas stream 18 deethanizer, and2-acetylene in the gas stream C2components in the device 22 hydrogenized hydrogen 15 and the device 24 into fractions with getting, essentially, 26 ethylene and ethane 28. Distillation residues 29 of ethnoastronomy columns 20 in the device 30 depropanizer and allocated With3-acetylene and diene in the stream With a3components 32 in the device 34 also hydrogenized hydrogen 15 and the device 36 into fractions with obtaining essentially of propylene 38 and propane 40. Similarly distillation residues from propanethiol columns 30 in the device 42 debutanizer with receiving stream C4components 44, which hydrogenized device 46.

Thread 485- and heavier products together with heavy products 8 from the front side of the system and hydrogen 15 send in the unit 50 for Hydrotreating gasoline fraction. This thread is C5- and heavier products hydrogenized diolefine and acetylene. In the second stage olefins gidrogenit, and sulfur compounds into hydrogen sulfide. Next, partially gidrogenizirovannye product 52 of the first installation of 50 for Hydrotreating gasoline fractions into fractions in the device 54 in which the top of the shoulder strap 56 are removed From5-C8components, resulting in bottoms 58 get With9- and heavier products. After that, the upper shoulder 56 in the device 60 is subjected to further hydrogenation, followed by separation into fractions in the device 62 with getting the top of the shoulder strap 64 saturated With5components and as bottoms gasoline product 66 consisting of saturated6-C5-components. Stream 64 C5components combined with a stream saturated With4products from the stage 46 hydrogenation and the combined stream 65, consisting of C4- and5components typically return in the pyrolysis furnace. In these pyrolysis furnace can also return ethane and propane streams 28 and 40.

In Fig.2 shows a process diagram of a modified version known in the art method, technological scheme of which is shown in Fig.1 and in which the OBR is you separate from C5components, as shown in Fig.1, when C5components are treated together with the gasoline fraction. In the embodiment of Fig.2 (C4- and heavier products in the form of bottoms propanethiol column 30 with heavy products 8 the beginning of the process is sent to distillation column 42, which in this case performs the functions pentanethiol columns, with the Department With the4- and5components in the upper chase 44. At the top of the shoulder straps 44 hydrogenized device 46 with obtaining essentially the same flow 654and C5components, as in the diagram according to Fig.1. Thread 48 bottoms pentanethiol columns 42, which in this case contains6- and heavier components, including components from the stream 8 heavy products, also referred to unit 50 for Hydrotreating gasoline fraction to partial hydrogenation, distillation column 54 to separate9- and heavier products and installation 60 for Hydrotreating the purpose of the final hydrogenation of the remaining stream 66 gasoline fraction with6-C8components exactly the same as in the circuit of Fig.1. As shown in Fig.2, is applied to five separate hydrogenation plants or plants for Hydrotreating.

The objective of these previously known methods is the selection of target fractions and selective hydrogenation With2- and3-acetylenes and dienes, as well as4- and heavier acetylenes, dienes and olefins without hydrogenation target olefins, i.e. ethylene and propylene. For example, selective hydrogenation propylene is not only essential for obtaining high-purity propylene, but the hydrogenation of methylacetylene and PROPADIENE contained in this fraction (collectively referred to as MAPD), allows to obtain an additional quantity of propylene with high product yield.

According to the present invention, these operations of separation and hydrogenation is at least partially carried out by catalytic distillation with hydrogenation. Catalytic distillation is a process in which ordinary distillation is combined with catalytic reactions. In the method according to the present invention, the catalytic reaction is hydrogenation. When the catalytic distillation in a distillation column used catalytic material, which serves as a catalyst for the reaction, and the nozzle column for rectification. This catalyst is om and hydrogenation with a catalytic distillation specifically addressed in the patents US 4302356, US 4443559 and US 4982022. Previously catalytic distillation has been described with reference to the cleansing rich in propylene materials containing small amounts and a limited number of acetylene compounds and diolefins order to receive the additional amount of the propylene hydrogenation and selection available and the resulting propylene (see PCT/US94/07758, international publication WO 95/15934). However, the present invention is the treatment of the cracking gas source stream containing significant quantities of components of the whole range of carbon numbers, including ethylene, propylene,3-acetylene and diene,4- and5-acetylene and diene and olefins, as well as With6- and heavier components, which include unsaturated substances. The present invention is not only hydrogenation acetylenes and dienes with additional quantities of propylene and other olefins, and hydrogenation With4and more high molecular weight olefins with getting alkanes without loss of any substantial amount of the propylene feedstock or newly formed propylene and without clogging the catalytic layers. Proposed in the present invention method in General and SNO present invention in the first embodiment, its implementation in accordance with Fig.3 distillation residues 29 ethnoastronomy columns refer to the column 68 for catalytic distillation with hydrogenation, usually with heavy products 8 the beginning of the process and the condensate from the compressor 31. Despite the possibility of using various well-known hydrogenation catalysts, one of the preferred catalysts is a 0.3 wt. % palladium oxide on spherical particles of alumina as a carrier with dimensions of about 1/8 inch (3.2 mm). Other examples of typical hydrogenation catalysts are metals of group VIII of the Periodic table of elements both individually and in combination and together with the promoters and modifiers, such as palladium/gold, palladium/silver, cobalt/zirconium and Nickel, preferably deposited on a typical carrier for catalyst. In column 68 are catalytic layer 70 in the processing section 71 above is usually located in the Central part of the area 74 of the input source material, and in the zone 73 Stripping light fractions below the area 74 of the input source material, are only means of fractionation, plates or nozzle. Thread 15 of the hydrogen injected into the column 68 of the lower catalytic layer 70. In column 68 support such distillation conditions, i.e. temperature and pressure at which the top ring is distilled off C3With4- and5-acetylene and diolefine hydrogenized mainly in the upper layer 70, and these MAPD hydrogenized to propylene, and C4and C5components hydrogenized to the corresponding olefins. Because acetylene and diene usually hydrogensource first, propylene or4- and5the olefins in this layer 70 hidrogenesse poorly or not hydrogensource at all. In the process of hydrogenation of acetylenes and diolefins impose only a sufficient amount of hydrogen. The upper shoulder 76 of the column 68 containing monounsaturated and saturated With3-C5components, refer to the column 78 containing processing section 81 of the plate or nozzle 80 and section 83 of the Stripping of light fractions plates 79 (or nozzle), followed by catalytic layer 82. Propylene is distilled off at the top of the shoulder strap in the device 84, and unsaturated With4- and5components, mainly olefins, hydrogenized layer 82 flow 15 hydrogen. Usually in a preferred embodiment, the catalytic distillation of the hydrogenation is carried out in the enrichment section of the column and not in the Stripping section of the light fractions. This is because in the catalytic layer can be formed over the high-molecular oligomers, code acetylene and diene removed already in the column 68. This significantly decreases the tendency to form oligomers.

In a preferred embodiment, the means of fractionation, such as a plate or nozzle, is placed between the insertion point of the source material in the column 78 and the catalyst layer 82. These plates are usually reduce the concentration of propylene in the catalytic layer 82, reducing losses due propylene hydrogenation and increasing the total number of propylene discharged into the stream 84. Propane and formed With4- and5-alkanes away in the form of still residue 85. Thread 85 of saturated C3-C5components typically return to the cracking furnace for an additional amount of the target product dehydrogenization, usually ethylene and propylene. Distillation residues 75 of the columns 68, which comprise primarily dehydrogenation6- and heavier components, hydrogenized advanced conventional hydrogenation installing 86 with a fixed layer, and then the device 87 separated into fractions with removal With9- and heavier components in the form of bottoms 88, and then subjected to additional hydrobromide in another acceptable hydrogenization the 92 is the average fraction, i.e., saturated With6-C8-components. Aromatic components of this stream can be removed by conventional technology. In this embodiment of the invention, which provides separation and reaction equivalent to that in ways, some of which were shown in Fig.1 and 2, two units 68 and 78 catalytic distillation with hydrogenation replace propanethiol column 30, hydrogenation installation 34, distillation column 36 and hydrogenation installation 46.

One of the problems associated with the hydrogenation of the flow of the source material of the type used in the implementation of the present invention is also loss of propylene. According to the present invention the flow of the upper shoulder strap withdrawn from column 68, includes all of propylene, coming into this column, plus an additional amount of propylene produced in the hydrogenation of MA and AP. Due to the fact that the catalyst is more selective in the hydrogenation ratio of more highly unsaturated acetylene and diene hydrocarbons compared to the hydrogenation of olefins, there is a high selectivity with a slight hydrogenation of propylene and other olefins or usucich sections 79 and 80 of the column 78. Hydrogen is injected only with a small excess in the stream 15 and thus to provide only the amount of hydrogen required for the hydrogenation of acetylenes and dienes to olefins. In column 68 is also supported by the high ratio of return flow. This reverse flow removes the heat of reaction. More important is that it allows to reduce the concentration of propylene in the liquid phase in the catalytic layer 70. Such a low concentration of propylene further weakens his tendency to hydrogenation.

As shown in Fig.4, an additional reactor with a fixed catalyst layer can be eliminated. This scheme differs from that shown in Fig.3 the fact that the column 68, the hydrogenation catalyst is placed in the Stripping section of the light fractions. In this column 68 catalytic layer 70 is processing section 71 above is usually located in the Central part of the area 74 of the input material, and the other catalytic layer 72 is placed in section 73 of the Stripping of light fractions under the area 74 of the input source material. Disc or nozzle section located below the insertion point of the initial material for the catalyst layer 72. The threads 15 of the hydrogen is sent to the column 68 for each of kataliticheskim the shoulder strap is distilled With3-C5components, a C6- and heavier products are removed as bottoms 75. MAPD,4- and5components hydrogenized mainly in the upper layer 70, and these MAPD hydrogenized to propylene, and C4and C5components hydrogenized to other olefins. Because acetylene and diene usually hydrogensource first, propylene or4- and5the olefins in this layer 70 hydrogensource poorly or not hydrogensource at all. Similarly in the lower layer 726and more high acetylene and diene and styrene hydrogensource first of alkenes. The upper shoulder 76 of the column 68 containing unsaturated and saturated With3-C5components, refer to the column 78 containing processing section 81 of the plate 80 and section 83 of the Stripping of light fractions catalytic layer 82. Propylene is distilled off at the top of the shoulder strap in the device 84, and unsaturated With4and C5components, mainly olefins, hydrogenized layer 82 flow 15 hydrogen. Propane and formed With4- and5-alkanes away in the form of still residue 85. Distillation residues 75 of the columns 68, all of which include hydrogensource6and the higher ianthe stream 75 may be divided into fractions device 87, removing as bottoms 889- and heavier components, and then further hydrogensulfate device 90 using flow 15 hydrogen to complete the hydrogenation. Product 92 is the average fraction, i.e., saturated With6-C8components, which can be used to remove aromatic components. Thus, in this embodiment of the invention, which provides separation and reaction equivalent to that in ways, some of which were shown in Fig. 1 and 2, two units 68 and 78 catalytic distillation with hydrogenation replace propanethiol column 30, hydrogenation installation 34, distillation column 36, hydrogenation installation 46 installation 50 for Hydrotreating to significantly save on the cost of the equipment.

One of the reasons that earlier in the Stripping section of the light fractions of the column, such as column 68, the hydrogenation is not performed (in particular, as it follows from PCT/US94/07758), is the probability of clogging the catalytic layer, such as layer 72. Hydrogenation acetylenes and dienes has the maximum probability of creating a blockage because of the formation of long-chain oligomers or petrogenesis in the processing section. Thus, in accordance with Fig.3 in section Stripping light fractions hydrogensource only olefins that substantially solves the problem of clogging. In Fig. 5 shows another design of the column 68, designed for an even more successful solution to the problem of clogging than in the construction shown in Fig.4. In this design layer 72 is divided into two or more separate layers 72A and 72W. Layer 72A may consist of more selective catalyst in the sense that it is normally primarily simply supports the hydrogenation of more highly unsaturated compounds. Thus, in the area in the column where there can be a certain amount of propylene, hydrogensource only acetylene and diene. On the other hand, the layer 72W may consist of more active and selective catalyst, which provides all other hydrogenation of unsaturated products found on this site. For example, the metal content in the catalyst layer 72W, in particular palladium oxide, may exceed the metal content in the catalyst layer 72A.

Another technique used in the construction of Fig.5 to prevent the hydrogenation of propylene in the upper section of the Stripping volatile to the still residue away with a pump 97 and cooled in the device 98, then Inuktitut back into the feed area of the source material 74 over the section 73 of the Stripping of volatile components. In another embodiment, shown in Fig.6, it is possible to divert steam flow, condensing device 98, and then through the device 97 to pump back into the upper part of the catalytic layer. In the exhaust steam flow decreases the concentration of oligomers and other heavy materials that return in the upper part of the catalytic layer. This pumping bypass provides an opportunity not only to remove heat of reaction and to enhance the wetting of the catalyst, but also be reduced by diluting the concentration of acetylenes and dienes, which are available and which in other circumstances showed a tendency to the formation of blockages.

Another factor that weakens the impact of the formation of oligomers in the diagram according to Fig. 4 is a high concentration of aromatic substances in section Stripping of volatile components. Fraction With6-C9components removed from the installation for steam cracking is predominantly aromatic. The concentration of acetylenes and dienes low. This is because such compounds in coil heaters cracking installation cyclists, forming aenichit the degree of clogging.

Another embodiment of the present invention shown in Fig.7, according to which the installation is 100 catalytic distillation with hydrogenation involves two catalytic layer 102 and 103 in the upper part above the insertion point of the source material and two catalytic layer 104 and 105 in the lower part below the insertion point of the source material. Between the insertion point of the source material and the catalytic section 104 need to place the disc section. MAPD,4and C5components hydrogenized mainly in the upper part, whereas With6- and heavier components hydrogenized mainly in the lower part. The upper shoulder 106 of pentanethiol 100 columns containing3-C5components direct propyleneamine column 108, which is basically saturated With3-C5components 112 produce propylene product, and the rest is returned to the pyrolysis furnace. Distillation residues 114 with6- and heavier components from pentanethiol 100 columns can be added directly to the gasoline fraction. In this embodiment, shown in Fig.7, applied technology, which to some extent similar to those shown in Fig.3. High co and propylene in the liquid phase. Bypass pumping circuit, denoted by the General position 107 is used with the same purpose as in the diagram according to Fig.5. In addition, the processing section also includes two separate catalytic layer 102 and 103 and is also provided with a bypass pump circuit 109. Usually in the catalytic layer 102 hydrogensource acetylene and diolefine, and in the catalytic layer 103 hydrogenized some or all With4-C5-olefins. The catalyst layer 102 is typically less active and more selective than catalyst layer 103. Bypass pumping circuit 109 serves to maintain a high mass flow rate in the catalytic layer 102, allowing you to adjust the temperature and concentration of reagents, and to maintain a high concentration of liquid in the catalyst.

Section Stripping light fractions also includes two catalytic layer, the upper layer 104 more selective than the bottom layer 105. Acetylene and diene, as well as sterols, usually hydrogenized in the catalytic layer 104, and the olefins are usually hydrogenized in the catalytic layer 105. The obtained product (88 and 92) is characterized by a low content of unsaturated substances that are acceptable for mixing with gasoline fraction without prior treatment is authorized in Fig.7, characterized by a significant loss of propylene and an increased tendency to clogging of the catalyst than technological schemes of Fig.3-6, but capital costs are lower than for any hydrogenation plants that are in the same column.

In Fig.8 presents another embodiment of the invention, which provides for the application of catalytic distillation with hydrogenation in combination with ethnoastronomy column. At the base ethnoastronomy columns 118 are placed one or more layers 116 with the hydrogenation catalyst. The top zipper of ethnoastronomy columns, which still contains2-acetylene, ethylene and ethane, are treated the same way as in the circuits of Fig.3-6. In the catalytic layer 116 in the lower part ethnoastronomy columns 118 can be completely or at least mostly hydrogensulfate3and more high acetylene and diene. Although the tendency to clogging of the catalyst and there are, nevertheless due to the high concentration of available aromatic products it is weaker. In addition, the use of two or more catalytic layers, and bypass pumping lines usually minimizes the tendency to clogging of the catalyst. Clogging capatilistic in ethnoastronomy column, the need for catalytic distillation and hydrogenation in propanethiol column 120, as is happening in the units shown in Fig.3-6, is missing. In this embodiment, in propanethiol column 120 is simply provided for the separation into fractions for discharge from the bottoms 78 propylene. In accordance with this scheme the rest of hydrogenation, which in ethnoastronomy column 118 is not completely, almost complete in pentanethiol column 94. As shown in Fig.8, in ethnoastronomy column 118 could be used side capacitor 117 is mounted on a bypass pump circuit that allows, in addition to circulate in the bypass, take the heat of the hydrogenation reaction.

There are other possible technological schemes that use these basic principles. For example, according to Fig.9 hydrocarbons are sent to the column 120, which in this embodiment performs the functions propanethiol columns. In this embodiment, the layer 122 catalytic distillation in the processing section is provided for the top plate 124 and the lower plate 126, and a plate 127 in the Stripping section of the light fractions. In the layer 122 catalytic distillation MA and DD hydrogenized mainly to propylene. Vysokogorii and allows you to create a sufficient flow rate for optimum performance of the catalyst. Distillation residues from the column, i.e., the flow 128, sent to pentanethiol column 130. This pentanethiol column has a layer of catalytic distillation located in the processing section, and a plate 134 in the Stripping section of the light fractions. In the layer 132 catalytic distillation of everything With4-C5-acetylene, dieny and olefins hydrogenized to C4-C5-alkanes. For removal of heat of reaction using a high ratio of return flow. Distillation residues 136 of pentanethiol column 130 is sent to the usual process of hydrogenation gasoline fraction. In accordance with Fig.10 apply a similar scheme, except that pentanethiol columns 130, there is a section of the catalytic distillation located in the Stripping section of light fractions, and it will have a product suitable for mixing with gasoline fraction. In Fig.10 also shows that each catalytic layer is divided into two sections. In addition, each layer of processing sections and layers section of the Stripping of light fractions are represented as divided into two independent sections, which may include catalysts of different activity. The heat of reaction promotes air pump cooling system 140 operating in Llandogo way.

Example
In the column for catalytic distillation with hydrogenation, containing 4000 g commodity palladium catalyst on aluminum oxide with palladium content of 0.3 wt.%, process was conducted by depentanizer. The top zipper of the column are condensed by cooling water and returned in the form of phlegmy. Total head product was taken partially in the form of vapor and liquid.

VAT residue of the column was re-heated using an electric heater to provide the Stripping steam. The raw product was injected into the column at a distance of approximately 15% from the bottom of the column. The pressure on the top of the column was maintained at 7.3 bar.

In the column was filed hydrocarbons at a speed of 2.8 kg/h of the following composition, wt.%:
Ethane - 0.02
Methylacetylene - 2,2
PROPADIENE - 1,13
Propylene - 46,88
Butane - 3,8
Butene - 15,4
Butadiene - 13,1
With5-hydrocarbons - 15,0
With6-hydrocarbons and higher - 2,47
100
A stream of pure hydrogen was introduced into the column at the point of introduction of the hydrocarbon feedstock. Hydrogen was introduced into the flow at a speed of 1.7 moles per mole methylacetylene + PROPADIENE + butadiene.

Below is the total transformation of C3- and4-acetylenes and dienes, %:
Mutilate methylacetylene (MA) and PROPADIENE (PD), %:
The total selectivity MA + PD to propylene - 68
Selectivity MA + DD K6-hydrocarbons - 1
Selectivity MA + PD to propane - 31
Thus, the speed of propylene stream leaving the catalytic system, higher than the content of propylene in his introduction.

Total education butane is 12% of the total number of input stream butadiene + butenes. Thus, almost 100% of the butadiene is converted to butenes and 12% of butenes is further converted to butane.

Experimental data were carried out over the past 45 days with downloads of the same catalyst. During this period of time was not observed deactivation of the catalyst.


Claims

1. The method of processing recerving source material containing hydrogen, C2components, including ethylene, With3components, including propylene, acetylene and diene,4- and5components, including acetylene, dieny and olefins, and C6- and heavier components, including unsaturated compounds, for separation of ethylene and propylene and hydrogenation With3-acetylenes and dienes with additional quantity is in and olefins to saturated compounds and hydrogenation With6and more high molecular weight unsaturated compounds to a mixture of olefins and saturated compounds without significant hydrogenation of ethylene and propylene, comprising the following stages: A. the release of hydrogen and C2components; b. the allocation of ethylene as a product selected from C2components, century introduction of material with3- and heavier components and a quantity of hydrogen in the area of input material reactive distillation column comprising a processing section over the area of input material and the section of the Stripping of light fractions beneath the area of the input original material, while at least in the enrichment section contains a hydrogenation catalyst; the separation by distillation With6and more high-molecular unsaturated components in the form of bottoms; D. introduction6and more high-molecular unsaturated components in the form of bottoms in contact with hydrogen and a hydrogenation catalyst, as a result of these6and more high-molecular unsaturated components hydrogensource to C6- and heavier olefins and saturated compounds; that is, the Stripping3- With4- and5-comm hydrogenation in dressing area with obtaining top of the shoulder strap and keep concentrating zone conditions, including the concentration of hydrogen generated by the mentioned amount of the hydrogen, resulting in3-acetylene and diene hydrogensource with the formation of additional quantities of propylene and consequently at least partially hydrogenized4- and5-acetylene, dieny and olefins, and W. separation and isolation from the top of the shoulder strap as a product of propylene and further hydrogenation is contained in the upper chase at least partially hydrogenating4- and5-acetylenes, dienes and olefins with getting saturated With4- and5connections.

2. The method according to p. 1, in which the Stripping section of light fractions also includes a hydrogenation catalyst and in which the mentioned stages (d) and (e) distillation and hydrogenation With6- and heavier components takes place simultaneously in the Stripping section of the light fractions.

3. The method according to p. 2, in which stage of selection propylene is a phase separation into fractions with the separation of propylene from C4- and5components.

4. The method according to p. 3, in which6- and heavier components include6-C8-components9and more polymer sciense ser the I top of the shoulder strap, including almost all6-C8components, and bottoms, including almost all9- and heavier components, and further hydrogenation of the upper threshold with6-C8components.

5. The method according to p. 2, in which graciously source material additionally includes heavy cracking gasoline, which before stage (a) selection2components of recerving source material emit at least part of this heavy cracking gasoline and which additionally includes the stage of filing a dedicated heavy cracking gasoline together with3- and heavier components and hydrogen in the reactive distillation column.

6. The method according to p. 1, in which stage (a) selection2components from the source material with obtaining the remaining material with3- and heavier components and stage (C) the introduction of this material with3- and heavier components and hydrogen in the reactive distillation column containing a hydrogenation catalyst, include the stage of the introduction of this source material into the reaction-distillation column, the upper part of which includes Renou section, containing the specified catalyst for joint allocation With2components and hydrogenation With3- and heavier components.

7. The method according to p. 1, in which graciously gaseous source material was obtained at the stage of cracking of the hydrocarbon starting material, in which3- and heavier components further include propane and which referred to the stage of distillation of the material with3- and heavier components include phase separation of propane and saturated With4- and5components and return the selected propane and saturated With4- and5components on the stage of cracking.

8. The method according to p. 2, wherein stage (d) and (e) distillation and hydrogenation With6- and heavier components in the Stripping section of light fractions further include stage pumping with the presentation of the material in the crawl from a point below the catalyst hydrogenation section of the Stripping of light fractions in the point above catalyst hydrogenation section of the Stripping of light fractions.

9. The method according to p. 8, in which the hydrogenation catalyst in the Stripping section of light fractions includes the upper section of the hydrogenation catalyst and the bottom section of the spacecraft is it active hydrogenation catalyst in the lower section.

10. The method according to p. 9, which additionally includes a step of pumping with the presentation of the material in the crawl from a point below the upper section at a point above the upper section.

11. The method according to p. 1, in which stage (g) allocation of propylene from top of shoulder strap includes the following stages: (I) the introduction of the upper shoulder strap in the area of input material, the second reactive distillation column comprising a processing section over the area of input material and the section of the Stripping of light fractions below the zone input source material, the Stripping section of light fractions which contains a hydrogenation catalyst; (II) the introduction of hydrogen into the second reactive distillation column at a point below the catalyst hydrogenation; (III) the distillation of propylene top of a shoulder strap and hydrogenation With3- With4- and5components.

12. The method according to p. 1, in which stage (g) allocation of propylene from top of shoulder strap includes the following stages: (I) the introduction of the upper shoulder strap in the area of input material, the second reactive distillation column comprising a processing section over the area of input material and the section of the Stripping of light fractions below the zone input source material, the Stripping section of light fractions which soda is below hydrogenation catalyst; (III) the introduction of material with3- and heavier components in a number of reactive distillation columns comprising at least one reactive distillation processing section containing a hydrogenation catalyst, and at least one reactive rectifying section Stripping light fractions containing a hydrogenation catalyst; (IV) introduction of hydrogen in the reactive distillation processing section and the Stripping of light fractions; (V) the hydrogenation of at least one3-acetylenes and dienes to propylene in one of the reactive distillation processing sections without hydrogenation of propylene; (VI) at least partial hydrogenation With4- and5-acetylenes, dienes and olefins to saturated compounds in one of the reactive distillation sections; (VII) the distillation of propylene as the product of C4- and5components and (VIII) the hydrogenation With6and more high-molecular unsaturated components in one of the reactive distillation sections bog light fractions.

13. The method of processing recerving gaseous source material containing saturated With3components, including propylene, heathenishly3-acetylenes and dienes and hydrogenation of at least one unsaturated C4and unsaturated With5components without hydrogenation of propylene by selective hydrogenation With3-acetylenes and dienes in the first layer of catalytic distillation in the first catalytic distillation and thereby gain additional propylene, distillation, these propylene and an additional amount of propylene in the top of a shoulder strap and receiving material containing unsaturated With4- and5components, and non-selective hydrogenation of at least one unsaturated C4components and unsaturated With5components in the second layer of catalytic distillation in the second catalytic distillation.

14. The method according to p. 13, in which the first layer of catalytic distillation is a processing section of the first catalytic distillation, and the second layer of catalytic distillation is a processing section of the second catalytic distillation.

15. The method according to p. 13, in which the first layer of catalytic distillation is a processing section of the first catalytic distillation, and the second catalytic layer

 

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