GB2287250A - Gasoline production using dehydrocyclodimerisation - Google Patents

Abstract

A process for gasoline production involves fractionating a hydrocarbon feed 1 into C1-C3, C5-C6 (both optional), C2-C5, gasoline-range and heavier-than-gasoline streams, the C2-C5 stream 10 being dehydrocyclodimerised under pressure to produce aromatics, the product 14 of this reaction being cooled and condensed, with the condensed liquid 15 containing H2, propane and C6+ hydrocarbons being recycled into the fresh incoming feed which is eg crude oil or a gas condensate. The product 14 is heat-exchanged with the incoming combined feed 4 and the hotter fractions 9, 18 are heat exchanged with the stream 10. <IMAGE>

Description

PRODUCTION OF GASOLINE FROM CRUDE OIL OR GAS CONDENSATE BY DIRECT INTEGRATION WITH DEHYDROCYCLODIMERIZATION OF C3'S AND C4'S.

DESCRIPTION FIELD OF INVENTION The subject process relates to a hydrocarbon conversion process. Specifically, the subject process relates to a process for the conversion of a light aliphatic hydrocarbon such as propane and butane in crude oil or gas consensate to benzene or other aromatic hydrocarbons, which are mixed with the feed and a C5/C6 stream and/or a gasoline stream directly drawn off from the feed fractionation device. In a catalytic conversion zone the light aliphatic hydrocarbons are converted to aromatic hydrocarbons by a dehydrocyclodimerization reaction, with hydrogen also being produced. The resultant consensable hydrocarbons, which comprise of aromatic hydrocarbons, are then passed into the main fractionation device from whence the products and the feed to the dehydrocyclodimerization reaction zone are drawn. The heat from the dehydrocyclodimerization reaction zone provides heat for the feed to the main fractionation device and the rundown products partially provide the heat for the dehydrocyclodimerization reaction zone. This invention also relates to the design and operation of facilities employed to recover condensable hydrocarbons from a natural gas stream.

INFORMATION DISCLOSURE There are a large number of references that describe the conversion of light aliphatic hydrocarbons to aromatic hydrocarbons but few that directly convert these hydrocarbons for directly producing C5/C6 and gasoline streams in one process For instance, U.S.Pat. No 2,992,283 issued to J.Eng describes the conversion of propylene a variety of higher molecular weight saturated and unsaturated hydrocarbons including aromatics using a treated crystalline aluminosilicate as the catalyst. U.S Pat No 4,347,394 issued to C.M.Detz et al describes the conversion of CS-plus hydrocarbons to aromatics using a non acidic zeolite supporting a platinum compound. U.S Pat No. 4,451,685 presents a process for conversion of ethylene and/ or propylene to gasoline blending stock over a crystalline borosilicate catalyst containing specific metals U.S Pat No 4,329,532 issued to P.J. Conn et al describes the conversion of C4minus olefins or mixtures of olefins and paraffins to aromatic hydrocarbons using a catalyst that comprises a crystalline silicate having a specified composition, crystalline size range, and X-ray diffusion pattern.

A review of dehydrocyclodimerization was published at page 191 of Volume 18,No 2 (1979) of Industrial and Engineering Chemistry- Process Design and Development by Caisery. U.S.

Patent No. 4,180,689 issued to E.E.Davies et al describes the conversion of C3-C8 aliphatic hydrocarbons to aromatic hydrocarbons in a process that employs a catalyst comprising gallium supported on an aluminiosilicate. U.S Pat No.3,761,389 issued to L.D Rollman et all describes an improved process for converting C2 to 400 degree Fahrenheit hydrocarbons to aromatics over a ZSM-5 type catalyst.

U.S Pat No 4,528,412 issued to P.C Steacy is pertinent for its description of a production recovery method for dehydrocyclodimerization process and U.S Pat No 4,677,235 issued to John R. Mowry is pertinent for its description of a production recovery method for producing C5 -plus aromatic from the dehydrocyclodimer zation process using a natural gas feed.

A review of Hydrocarbon Processing Dec 1991 article "Processing LPG to BTX product" describes the application for the conversion of ilie C3-C5 aliphatic hydrocarbons to Benzene and C6+ aromatics.

Much development has occurred in the art of crude oil and gas condensate processing including the common processing techniques including partial condensation by indirect heat exchange, auto refrigeration by the steps of compression, cooling and expansion, and fractional distillation. U.S Pat Nos 3,393,527 issued to L.K.Swensen et al.; 3,791,157 issued to R.R.Tracy et al 4,004,430 issued to S.M.Solomon et al and 4,070,165 issued to J. W.

Colton are believed pertinent for their showing of the use of these techniques to separate the gas conensates and gas condensate and compressed gases from a natural gas stream which are methods of producing the feed stream., and for their description of the fractionation of hydrocarbons from a natural gas stream.

BRIEF SUMMARY OF THE INVENTION The invention is a unique process for the production of a gasoline streams from crude oil and/or gas condensate in an integrated unit using the product of C6 aromatics from the propane & butane in the feed and recycle stream. One of the novel features of the subject invention is the integration of a catalytic dehydrocyclodimerization reaction zone with a main fractionation section. The reaction products of the catalytic dehydrocyclodimerization reaction zone are partially condensed and the produced condensate is recycled to the main fractionator with the fresh feed. The integration of the catalytic dehydrocyclodimerization reaction zone with the main fractionation facilities can provide significant economic efficiencies when employing revamped or existing fractionation facility. A significant feature of the subject invention is the application for gas condensate and crude oil feeds and the fact that there is no requirement to compress and recycle large quantities of produced gases from the catalytic dehydrocyclodimerization reaction zone.

A broad embodiment of the invention may be characterized as a hydrocarbon conversion process which comprises the steps of cooling and condensing a hereinafter characterized reaction zone effluent stream comprising hydrogen, propane and C6-plus hydrocarbons into a separator zone and separating the condensed liquids from the offgases: mixing or otherwise the condensed liquids with the incoming fresh gas condensate feed or crude oil as the first process stream, and partially or total preheating this feed stream against the reactor effluent and feeding this stream into a main fractionation zone and therein separating the combined feed stream and recycled reactor zone condensate into a C3-minus off gas, C3-C5 stream (defined as the first process stream) , C5/C6 stream(optional), gasoline stream and bottoms stream. The bottoms stream can be subsequently separated into Kerosene, Gasoils and Fuel Oil products in standard fractionation facilities; passing the first process stream into a catalytic dehydrocyclodimerization reaction zone, partially preheated against product streams of the fractionation section so that the second process stream is maintained at dehydrocyclodimerization conditions and producing the previously referred to reaction zone effluent stream.

BRIEF DESCRIPTION OF THE DRAWINGS The drawing is a simplified process flow diagram illustrating several embodiments of the invention. In the basic flow of the process propane & butane present in the feed enters through line 1 , is separated in the fractionation zone 7, and is converted to a mixture of C6-plus aromatics and hydrogen in the dehydrocyclodimerization reaction zone 13. The reactor effluent line 14 flows to the cold vapour-liquid separator from where the condensed liquids line 15 is mixed with the incoming stream 1. The combined feed is preheated against the dehydrocyclodimerization reaction zone effluent 14 and is feed to the fractionator zone in line 4.

DETAILED DESCRIPTION Dehydrocyclodimerization processes have been developed for the conversion of light aliphatic hydrocarbons to aromatic or non aromatic C6+ hydrocarbons. The basic utility of theses processes is the ability to convert low value, highly available C3 and/or C4 hydrocarbons into C6+ aromatics which are blended directly with naphtha components in the feed to produce gasoline for direct production without the necessity of catalytic reforming. The process may therefore be performed to upgrade the value of the hydrocarbons. it may also be desired to correct an overabundance of C3 and C4, or facilitate the conversion of Crude oil , gas condensate or gas condensate and produced gases into distillate fuel products at remote locations, for example oil fields and pipeline, in order to meet local requirements for such products. It is the objective of the subject invention to provide a process to make fuel distillate products, gasoline, kerosene and diesel from Crude oil , gas condensate or gas condensate. It is a further objective of the subject invention to provide a more economic dehydrocyclodimerization process and utilize this process for the production of gasoline.

The subject process achieves these objectives by employing the unique integration of fractionation and heat integration with the dehydrocyclodimerization reaction zone.

Conventional fractionation of crude oil , gas condensate and gas condensate with compressed gases must normally be designed to accommodate a variety of materials having an extreme boiling range similar to that of the dehydrocyclodimerization reaction zone. Existing or new crude oil fractionation, gas condensate stabilization units or gas concentration plants may therefore be adaptable to the subject process and function as the relatively expensive product recovery section of the dehydrocyclodimerization reaction zone. Additionally, for relatively small units for remote location the dehydrocyclodimerization reaction zone can be designed as two parallel semi-regerative reaction sections operated such that each reaction section is design 75% of the capacity. These factors greatly reduce the capital cost of a dehydrocyclodimerization reaction zone and are particularly suitable for small pre-fabricated skid-mounted units to be transported to remote locations. Additionally the fractionation zone will also function as the feed preparation zone producing the required feed stock to the dehydrocyclodimerization reaction zone. The subject process also provides a mean of partially recovering the C3's and C41s paraffins for recycle to the reaction zone.

In the subject process the C3's and C4's in a feed of aliphatic hydrocarbons, from a crude oil, a gas condensate or a gas condensate with compressed gases are passed into a dehydrocyclodimerization reaction zone that converts a portion of the entering hydrocarbons into aromatic hydrocarbons. The term "reaction zone" is intended to indicate the totality of the equipment employed in the conversion step wherein the feed hydrocarbons are passed through a reaction chamber(s), which may contain several beds of catalyst and interstage heaters, etc.

The composition of the effluent stream of the dehydrocyclodimerization reaction zone will depend upon such factors as the composition of the feed to the dehydrocyclodiinerization reaction zone, which is effected by the composition of the fresh feed stock, and the operating parameters of the fractionation zone. The presence of olefinic hydrocarbons within the feed stream to the dehydrocyclodimerization reaction zone would tend to cause the production of branch chain or acyclic C6+ hydrocarbons. However, few olefinic hydrocarbons are normally present in the natural fresh feeds of crude oil , gas condensate or gas condensate with compressed gases. Therefore the recycle of the olephinic components from the condensed dehydrocyclodimerization reaction zone effluent is insignificant compared to the fresh feed.

Any produced branch chain or acyclic C6+ hydrocarbons end up in the gasoline stream as high octane components. When processing a dehydrocyclodimerization reaction zone feedstock comprising of propane or butane or mixtures thereof, the reaction zone effluent will contain benzene, toluene, ethylbenzene, a mixture of the various xylenes, styrene, N-propyl benzene, cumene, methyl benzene, trimethyl benzene, methyl propyl benzenes, dimethylethyl benzenes, indane, C11 alkylbenzenes, naphthalene, methyl-naphthalene, dimethylnaphthalene and a very small amount of heavy aromatic compounds. The majority of these when introduced with the fresh feed to the fractionation zone will provide the high octane components for the resultant directly drawn gasoline product.

The feed compounds to the dehydrocyclodimerization reaction zone are light aliphatic hydrocarbons having from 2 to 5 carbon atoms per molecule. Feed streams to the dehydrocyclodimerization reaction zone may comprise various mixtures of these compounds.

It is preferred that over 50 mole per cent of the feed to the dehydrocyclodimerization reaction zone have three or more carbon atoms per molecule. Some butylene and propylene may be present. The preferred concentration of C5 for production of benzene, toluene and xylene products for production of these specific products is less than 10 mole per cent. However, in the subject process the objective is the produce high octane components for the production of gasoline at an economic basis. In this case the preferred concentration of C5 in the feed is a function of the capital costs associated with the fractionation zone and the relative prices of the products. The preferred concentration of C5 could be as much as 25 mole per cent.

The configuration of the dehydrocyclodimerization reaction zone and the composition of the catalyst employed within the reaction zone are not basic elements of the invention to limiting characteristics of the invention. Nevertheless, in order to provide a background to the subject invention, it is felt useful to describe the preferred reactor systems for the use in the invention.

For large units the system comprises a moving bed radial flow multistage reactor such as is described in U.S Pat Nos 3,652,231; 3,692,496, 3,706,536; 3,785,963; 3,825,116; 3,839,196; 3,839,197, 3,854,887, 3,856,662, 3,918,930, 3,981,824; 4,094,814, 4,110,081 and 4,403,909.

These patents also describe catalyst regeneration systems and various aspects of moving catalyst bed operations and equipment. This reactor system has been widely employed commercially for reforming of naphtha fractions. Its use has also been described for dehydrogenation of light paraffins.

The moving bed reactor system employs a spherical catalyst having a diameter between about 1/64 and 1/2 inch. The catalyst preferably comprises a support material and a metallic component deposited on the support material and a metallic component deposited on the support material as though impregnation or coprecipitation. The previously cited references point out that the current trend is the use of a zeolite support material, with the catalyst referred to in the art as a ZSM-5 type zeolite being often specified as a preferred material.

When properly formulated, it appears this zeolite material by itself has significant activity for the dehydrocyclodimerization reaction. Further information on such zeolitic catalysts for dehydrocyclodimerization reaction can be obtained from European patent application No 83 20114229 by E.P.Kieffer. However, it is still preferred to employ a metallic component within the catalyst system to increase the activity of the catalyst. The preferred metallic component is gallium as described in the previously cited U.S Pat No 4,180,689. The catalyst may contain from about 0.15 to 2.4 weight per cent gallium that is preferred exchanged or impregnated into the zeolitic component of the catalyst rather that forming a portion of the original (as produced) zeolit. A preferred range of the gallium component is from 0.3 to 1.0 weight per cent. For further information on catalyst and operating conditions for the dehydrocyclodimerization reaction zone may be obtained from U.S Pat No 4,565,897. It is not particularly pertinent that this patent refers to feed streams from between 10 to 50 weight per cent ethane.

The zeolite material, preferably ZSM-5, is normally bound during the particle forming stage with another material primarily to increase the strength and durability of the catalyst. This binding material is often clay or alumina. It is highly preferred that this binder comprises an alumina, as can be prepared by the gelation of a hydrosol precursor in accordance with the well-known oildropping method. For instance, an alumina hydrosol can be prepared by digesting alumina in aqueous hydrochloric acid and/or aluminium chloride. The final composite can be formed in a variety of shapes or by oil-dropping and finished using conventional catalyst manufacturing techniques For small unitsthe system comprises fixed bed multistage reactors that are regenerated when the activity of the catalyst declines. In order to ensure a continuous operation the preferred design in this mode has two reaction sections operated in parallel and design for 75% of capacity. This semi-regerative reactor system has been widely employed commercially for reforming of naphtha fractions. The major advantage of designing the reactor system for small unit in this manner is that the design can be easily pre-fabricated and skid-mounted and thereby reducing the problems of transportation. This is of particular relevant for remote locations.

The dehydrocyclodimerization reaction zone for the subject process is preferably operated at a temperature between 920 degrees - 1050 degrees Fahrenheit (487 degrees - 565 degrees Celsius) a pressure up to 100 psig (689 kPa g) and a liquid space velocity of 0.5 to 6.0 hr-1.

The advantages of operating the dehydrocyclodimerization reaction at relative high pressures are that the operation of the fractionation zone can be operated without the requirement of a pump for the condensate produced from the dehydrocyclodimerization reaction effluent. This substantially simplifies the design and is of significant importance for small units destined for remote locations.

It is believed that those skilled in the art of petroleum and petrochemical process design may determine proper operating conditions, vessel designs, and operating procedures for the subject process through the use of standard process design techniques after having now appraised of the overall flow of the process. The fractionation zone employed in the process preferably contains trayed fractionation columns having valve type trays and being of relatively standard design. Suitable fractionation zones may be readily designed by those skilled in the art. The operating conditions required in the frac+:nation zones are dependent upon the compounds being separated, the desired separation and the economics of the unit.

The illstration of the flow of the subject process presented in the drawings has been simplified by not illustrating many required pieces of conventional equipment that are not pertinent or necessary to a discussion of the subject invention. These engineering features include control systems, pumps and compressors, reactor and fractionation column internals, overhead condensing systems and reboiling systems for the fractionation columns and similar process equipment of a generalized nature.

Referring now to the drawing for the gas condensate feed, the gas condensate enters the process through line 1. Preferably, this gas condensate feed stream has been treated in suitable facilities for the removal of water. Any, hydrogen sulphide and other sulfur compounds are preferably treated in the streams produced in the fractionation zone. The gas condensate is pumped in the pump 2 and mixed with the dehydrocyclodimerization reaction effluent condensate 15 to produce the combined stream 4. The combined feed stream 4 is heated against the dehydrocyclodimerization reaction effluent in heat exchanger 3 and fed through process line 4 to the fractionation zone 7. This stream comprises propane, propylene, butane, butylene, C5 and C6 hydrocarbons including the benzene, toluene, xylene and other aromatic hydrocarbons produced in the dehydrocyclodimerization reaction zone 13 with an equilibrium concentration of the more volatile materials from the vapour-liquid separator 16 of the dehydrocyclodimerization reaction effluent 14. This mixed phase or vapour phase stream (depending on the gas condensate composition) will therefore contain some finite quantity of hydrogen, methane & ethane Fractional distillation is the preferred method of performing the separation of the various components of the stream of line 4 , although other separatory methods could be used in addition to or to the exclusion of fractional distillation within the overall zone. Nevertheless, the entering materials are preferably separated into a small light gas stream comprising Cl-C3's discharged through line 8, a heavy hydrocarbon product stream comprising hydrocarbons boiling above 390 degrees Fahrenheit (200 degrees Celsius) through process line 6, a gasoline hydrocarbon stream to meet required specification through process line 9, and a C5/C6 hydrocarbon product stream through process line 5 and a first process stream comprising the C3-C5 stream (with up to 25 mole per cent C5) which it is desired to charge to the dehydrocyclodimerization reaction zone, carried by process stream 10. For most types of gas condensate or crude oil fresh feed the discharge for process stream 8 is expected to be small. The split between the presence of C5 hydrocarbon in the process streams of lines 5 and 10 need not be exact since it is acceptable to charge C5 hydrocarbons to the dehydrocyclodimerization reaction zone 13 The lack of any requirement for a precise separation of the various hydrocarbons within the fractionation zone allows the utilization of lower cost fractionation equipment and/or the operation of the fractionation columns in a mode that reduces the utility costs of the operation as by minimizing reflux and stripping requirements. The control of the octane quality of the gasoline is achieve by drawing off less C5/C6 from the fractionation column in process stream 5 and drawing more gasoline in stream 9 to reduce the Octane Number in the gasoline product and by drawing off more C5/C6 from the fractionation column in process stream 5 and drawing less gasoline in stream 9 to increase the Octane Number in the gasoline product. Additional controls considered include varying the ration of fresh feed in process stream line 1 to dehydrocyclodimerization reaction zone effluent condensate process stream 15 and/or varying the dehydrocyclodimerization reaction zone 13 temperature.

The hydrocarbon stream of line 10 is first heated by indirect heat exchange in heat exchangers 11 exchanging heat with the gasoline product stream 9 and fractionation heavy stream 18. It is then passed into the fired heater 12 that raises the temperature ofthe materials in line 10 to the desired inlet temperature of the downstream dehydrocyclodimerization reaction zone 13. The thus heated hydrocarbons will flow into the reaction zone 13 wherein they are contacted with beds of dehydrocyclodimerization catalyst at suitable operating conditions. The reaction section can be either the multi-stage moving bed operating system or the semi-regenerative operating system. In either case the preferred arrangement is with three reactors in sequence with inter-stage heating to replace the heat of reaction of the highly endothermic reaction.

There is thus produced a vapour phase reaction zone effluent carried by line 14 that will comprise an admixture of the unconverted charge materials including ethane, propane and butane and the product materials of the reaction including hydrogen, benzene, toluene, xylene and other C6+ aromatic hydrocarbons. The catalysed dehydrocyclodimerization reaction is highly selective to the production of aromatic hydrocarbons when processing a totally paraffinic feed stream. A minor amount, less than 2 mole per cent, of C6-plus acyclic hydrocarbons may be produced during the dehydrocyclodimerization reaction. If for some reason there is any appreciable percentage of olephinic hydrocarbons in the feed stream, the proportion of the acyclic hydrocarbon produced will increase. The reaction zone effluent is then cooled in indirect heat exchange in the means 3 against the combined feed stream 4 to the fractionation zone 7. It is then further cooled and partially condensed by indirect heat exchange as though through the use of the air cooled indirect heat exchange means 15. The effluent stream of the reaction zone 14 is then passed into the vapour-liquid separation vessel 4. The separation vessel is preferably operated at 70-90 psig ( 482-620 k Pa g ). Reference may be made to U.S Pat 4,677,235 where the preferred vapour-liquid separation pressure is 400 psig (2,758 k Pa g) and a main compressor is require. In the subject process no main compressor is required for either the bulk reactor effluent or the bulk reactor produced noncondensable gases. However, it may be preferable to include a small recycle compressor for the reaction section. Those skilled in the art will recognise that the embodiment illustrated in the drawing is subject to appreciable variations beyond that already discussed. For example, various alternative heat exchange methods could be employed to cool or heat both the feed and effluent streams of the reaction zone. It is contemplated that a number of techniques could be used to partially or totally separate the reactor effluents and that a significant variation of fractionation is possible in the structure and orientation of the fractionation zone.

However, the subject process lends itself to simplicity in the overall design and implies by the invention itself a plant with minimum capital cost for equipment and minimum operating and maintenance cost by minimising and simplifying the use of rotating equipment. The is of particular importance for small unit for installation in remote locations.

As the fresh feed to the subject process is relatively low in methane and ethane it is preferred to exclude the recovery of these components for economic reasons. However, Those skilled in the art will identify standard methods for their recovery. The preferred routing of these components is to provide fuel gas and are derived principally from the process stream in line Q The bulk reactor produced non-condensable gases in stream 17 contain hydrogen, methane, ethane, ethylene, propane, propylene, butane and some C5 + components. For applications where the recovery of the C3+ components is a low priority the preferred routing of this stream is to fuel gas. However, for applications where the recovery of the C3+ components is a high priority this stream can be routed to a number of separation processes including adsorption-stripping in a fractionation column, pressure swing adsorption, partial condensation through the use of low temperatures in a cryogenic separation system similar to the "cold boxes" employed for gas recovery and sepa.ation, or through the use of membranes that selectively allow the passage of one or more hydrocarbons. The use of either adsorptionstripping and/or membranes are the preferred options. In the adsorption -stripper option the preferred absorbing oil is the produced gasoline that is recycled to the main fractionation zone 7 for recovery.

In one embodiment of the invention some of the fresh feed is in the vapour state and is compressed and partially condensed and than passed to a vapour-liquid separator so that condensate is primarily a C3+ liquid with a small amount of C2's. The light gas condensate produced is pumped and combined with the feed stream 4 to the fractionation zone 7. In this way additional C3-C4's become available to be passed to the dehydrocyclodimerization reaction zone. The off gas from the vapour-liquid separator is produced as a product.

In one embodiment of the invention some the fresh feed is a crude oil. In this event the preheat from the dehydrocyclodimerization reaction zone effluent is insufficient to vaporise the gasoline components in the feed and an auxiliary fired heater is added to the process stream 4, or alternatively, the fractionation zone incorporates a fired reboiler at the bottom of the main fractionation column. The bottom drawoff can then be passed into a second fractionation column where Kerosene and Diesel are draw off as additional products.

In one embodiment of the invention the produced non-condensable gases in stream 17 contain hydrogen, methane, ethane, ethylene, propane, propylene, butane and some C5 + components are compressed to 450 psig (3102 k Pa g) absorbed in an absorber column to recover the C3+ components which are routed with the absorption oil (gasoline) to the fractionation zone 7.

The resultant gas containing hydrogen, methane, ethane, ethylene, with a small amount of propane and propylene is processed through the use of membranes , or alternative, that produces a hydrogen rich stream, typically greater than 75 mole per cent Hydrogen and a C2 and C3 stream that can be if desired routed to the fractionation zone 7 for recovery of the C3's or routed to fuel gas. The produced hydrogen rich stream can then be routed to an isomerization process with the C5/C6 stream produced in the fractionation zone for further octane enhancement of the fresh feed. In this way the hydrogen is further utilised.

In one embodiment of t dehydrocyclodimerization reaction, the operating conditions employed within the dehydrocyclodimerization reaction zone, the fractionation schemes employed within the process flow, the remoteness of the location, the size of the unit and the local requirement for fuel distilled products and the difficulty of obtaining these products locally.

As previously indicated, it is preferred that the fresh feed is treated for the removal of any significant amounts of water. The sweetening of the produced products from the fractionation zone is only required if the catalyst in downstream processes or the product specifications require such treatment. It is preferable to dry and remove sulfur compound for the feed to the dehydrocyclodimerization reaction zone as the preferred zeolite type catalyst may be adversely affected by the presence of significant concentrations of water.

Claims (5)

1. PRODUCTION OF GASOLINE FROM CRUDE OIL OR GAS CONDENSATE BY

   DIRECT INTEGRATION WITH DEHYDROCYCLODIMERIZATION OF C3'S AND C4'S.

   CLAIMS What is claimed is: 1.A hydrocarbon conversion process that comprises the steps of: (a) combining the condendensed liquids of a hereinafter characterized reaction zone effluent stream comprising hydrogen, propane and C6-plus hydrocarbons with a fresh feed of crude oil, gas condensate or gas condensate and compressed gases and feeding them to a fractionation zone.

   (b) withdrawing from the fractionation zone offgas-stream C1's-C3's, a first processing stream containing C2's to C5's, and a first product stream that corresponds to a meeting a gasoline octane product specification, and a second product stream corresponding to any components heavier than the gasoline product (c) passing the first processing stream into a dehydrocyclodimerization reaction zone maintained at dehydrocyclodimerization conditions including a pressure under 100 psig, and producing the previously referred to reaction zone effluent stream.

   (d) passing the previously referred to reaction zone effluent stream through coolers and condensers into a vapour-liquid separator from where an off gas stream containing hydrogen, methane, ethane, ethylene, propane, propylene and small amounts of C4+ hydrocarbons is drawn as a third product stream and the condensed liquid is recycle as referred to previously
2. 2. The process of claim 1 wherein a C5/C6 stream is drawn from the fractionation zone.
3. 3. The process of claim 1 wherein the second product stream corresponding to any components heavier than the gasoline product are further separated into fuel distilled product in the fractionation zone.
4. 4. The process of claim 1 wherein no offgas-stream Cl's-C3's is drawn from the fractionation zone.
5. 5. The process of claim 1 further characterized in that a bed of a catalyst comprising gallium is present within the reaction zone 6 The process of claim I further characterized in that fresh feed gases are compressed and partially condensed and that the produced gas condensate is mixed with incoming fresh feed of crude oil or other gas condensate and passed to the fractionation zone.

   7 The process of claim 1 further characterized in that the combined fresh feed with the previously referred to reaction zone effluent stream condensate are preheated against the previously referred to reaction zone effluent stream.

   8 The process of claim 1 further characterized in that the feed to the reaction zone is partially preheated against the product streams drawn from the fractionation zone.

   9 The process of claim 1 filrther characterized in that the fractionation zone comprises of at least one fractionation column.

   10 The process of claim 1 fiarther characterized in that the fresh feed, whether crude oil, gas condensate or gas condensate with compressed gases comprises C6 hydrocarbons.

   11 The process of claim 1 further characterized in that the fresh feed of crude oil, heavy gas condensate or heavy gas condensate with compressed gases comprises additional preheating for the feed to the fractionation zone other than that provided by the previously referred to reaction zone effluent stream.

   12 The process of claim 1 further characterized in that the fresh feed of crude oil, heavy gas condensate or heavy gas condensate with compressed gases comprises auxiliary heating to the fractionation zone other than that provided by the previously referred to reaction zone effluent stream.

   13 The process of claim 1 further characterized in that the fresh feed comprises of all or part of an aliphatic and olephinic gas condensate or gas condensate with compressed gases.