METHOD FOR PRODUCING HIGH-OCTANE MOTOR GASOLINES OF LOW-OCTANE HYDROCARBON FRACTIONS, FRACTIONS OF GASEOUS OLEFINS AND OXYGENATES AND A PLANT FOR THE METHOD EMBODIMENT
20230235236 · 2023-07-27
Assignee
Inventors
- Vladimir Vladislavovich IMSHENETSKIY (Moscow, RU)
- Iosif Izrailevich LISCHINER (Moscow, RU)
- Olga Vasilyevna Malova (Moscow, RU)
- Andrey Leonidovich Tarasov (Moscow, RU)
Cpc classification
C10G3/49
CHEMISTRY; METALLURGY
C10G35/095
CHEMISTRY; METALLURGY
B01J29/405
PERFORMING OPERATIONS; TRANSPORTING
C10G2300/708
CHEMISTRY; METALLURGY
International classification
C10G35/095
CHEMISTRY; METALLURGY
B01J29/40
PERFORMING OPERATIONS; TRANSPORTING
Abstract
The invention relates to method and plant for the production of high-octane gasolines from raw hydrocarbon fractions, fractions of gaseous olefins and oxygenates. A method has been proposed, wherein the feedstock component flow is supplied to a unit for supplying flows to be treated, into the reactor, wherein the reaction is carried out in the presence of a zeolite-containing catalyst, high-octane gasoline is isolated by separation of the conversion product, while diverting simultaneously the reaction water and the exhaust gases. A reactor contains at least two reaction zones, between which there are further arranged means for mixing the reaction product from the previous reaction zone and the supplied oxygenates and olefin-containing feed-stock, whereas using the unit for supplying flows there is supplied a flow oxygenates and olefin-containing feedstock and the flow of raw hydrocarbon fractions into the first reaction zone of the reactor, and the flow oxygenates and olefin-containing feedstock into the second reaction zone of the reactor.
Claims
1. A method of producing gasoline from raw hydrocarbon fractions, fractions of gaseous olefins and oxygenates, wherein the feedstock component flow is supplied to a unit for supplying the flow to be processed into a reactor, wherein the reaction is carried out in the presence of a zeolite-containing catalyst, high-octane gasoline is isolated by separation of the conversion product, while diverting simultaneously the reaction water and the exhaust gases, characterized in that as a reactor, a reactor is used, which contains at least two reaction zones with a zeolite-containing catalyst, between which there are further arranged means for mixing the reaction product from the previous reaction zone and the supplied methanol and/or other oxygenates and olefin-containing feedstock, whereas using the unit for supplying flows there is supplied: separated and/or pre-mixed flow of methanol and/or other oxygenates and olefin-containing feedstock and the flow of raw hydrocarbon fractions into the first reaction zone of the reactor, and flow of methanol and/or other oxygenates and olefin-containing feedstock into the second reaction zone of the reactor.
2. A method of claim 1 characterized in that the flow rate of methanol and/or other oxygenates and olefin-containing feedstock to each reaction zone is controlled, and the temperature of the feedstock to be supplied to the reaction zone is controlled so that the maximum catalyst bed temperature in the reaction zone does not exceed 420° C. in the production of a base stock for the production of gasolines and 500° C. in the production of alkylaromatics concentrate, meanwhile, when decreasing the supply of methanol and/or other oxygenates and/or olefin-containing feedstock to the first reaction zone, the temperature of raw mixture supplied into the first reaction zone is increased, and vice versa.
3. A method of claim 1 characterized in that methanol and/or other oxygenates and olefin-containing feedstock are separated by means of said unit into at least two flows, the first flow is directed into the space upstream the first reaction zone where it is mixed with the flow of raw hydrocarbon fractions, and the second or subsequent flows are mixed in the downstream reaction zones with the conversion product from the upstream reaction zone.
4. A method of claim 1 characterized in that methanol and/or other oxygenates and olefin-containing feedstock are separated by means of said unit into at least one flow, which is directed to the downstream reaction zone, where said stream is mixed with the conversion product from the upstream reaction zone, wherein the first reaction zone is pre-supplied with a pre-mixed flow of methanol and/or other oxygenates and olefin-containing feedstock and the flow of raw hydrocarbon fractions.
5. A method of claim 3 characterized in that the flow is directed from said unit into the reaction zone directly or through a mixing zone located between the reaction zones and having means for mixing.
6. A method of claim 4 characterized in that the flow of methanol and/or other oxygenates and olefin-containing feedstock is mixed with the convertible hydrocarbon fractions in the space upstream the first reaction zone or more upstream in the direction of the hydrocarbon feedstock supply flow.
7. A method of claim 4 characterized in that prior to supplying to the first reaction zone, the mixed flow of methanol and/or other oxygenates and olefin-containing feedstock and the flow of raw hydrocarbon fractions are preheated.
8. A method of claim 1 characterized in that prior to the separation of methanol and/or other oxygenates and olefin-containing feedstock into multiple flows, a raw hydrocarbon fraction or a mixture of a raw hydrocarbon fraction and methanol and/or other oxygenates and olefin-containing feedstock are heated in two stages: at the first stage, a raw hydrocarbon fraction or a mixture of a raw hydrocarbon fraction and methanol and/or other oxygenates and olefin-containing feedstock are vaporized, heavier non-evaporated components are separated, and at the second stage, vaporized components are superheated.
9. A method of claim 5 characterized in that a bed of neutral material granules and/or a fraction of crushed quartz being placed upstream the front catalyst bed, or a line connecting the reactor spaces where the reaction zones are located, are used as mixing means.
10. A method of claim 1 characterized in that methanol and/or other oxygenates are supplied through said unit in the gaseous phase at a temperature of no more than 380° C. preventing its decomposition upon heating.
11. A method of claim 1 characterized in that a 1-2% aqueous solution of an industrial demulsifier is added to a mixture of hydrocarbons and water supplied to the separation at a ratio of 1:50-1:200 to the volume of the reaction water, the aqueous solution of the demulsifier is mixed with the input flow in a laminar static mixer or directly in a hydrocarbons and reaction water condenser located in the separation unit.
12. A method of claim 1 characterized in that isothermal reaction zones are used as the last one or two reaction zones of the reactor.
13. A method of claim 1 characterized in that adiabatic reaction zones containing no heat exchange devices are used as the last one or two reaction zones of the reactor, at the same time, the feedstock flow to be supplied to the final and/or penultimate reaction zones is further superheated no more than up to 500° C.
14. (canceled)
15. (canceled)
16. A method of claim 1 characterized in that a catalyst is used for producing liquid hydrocarbons of dimethyl ether based on crystalline pentasil-type aluminosilicate having a molar ratio of SiO.sub.2/AI.sub.2O.sub.3=25-100 characterized by the presence of residual amounts of sodium ions being equivalent to a content of 0.05-0.1 wt. % of sodium oxide, containing said crystalline aluminosilicate and binder, wherein it further contains cobalt oxide, oxides of rare earth elements and zinc oxide in the following ratio, wt. %: Zinc oxide: 0.5-3.0 Oxides of rare earth elements: 0.1-5.0 Cobalt oxide: 0.05-2.5 Crystalline aluminosilicate: 63-69.8 Binder: the rest.
17. A method of claim 1 characterized in that there is used a catalyst of the aromatization of C.sub.3-C.sub.4 gases, low octane hydrocarbon fractions and aliphatic alcohols, and mixtures thereof, based on the pentasil group zeolites, which contains a mechanical mixture of two zeolites having a different silicate module: a. Zeolite having a SiO.sub.2/AI.sub.2O.sub.3=20 previously treated with an aqueous solution of alkali modified with oxides of rare earth elements (REE) in an amount of 0.5-2.0 wt. %, and b. Zeolite having SiO.sub.2/AI.sub.2O.sub.3=82 having a residual amount of sodium oxide of 0.04 wt. % taken in the ratio of 1.7/1 to 2.8/1, and the remainder being a binder in an amount of 20 to 30 wt. % of the catalyst weight.
18. A method of claim 1 characterized in that the temperature of the last reaction zone is increased during the catalyst operation each time by 1-2° C. upon an increase in allowable values of methanol concentration in the reaction water.
19. (canceled)
20. (canceled)
21. (canceled)
22. A plant for the production of gasolines from raw hydrocarbon fractions, fractions of gaseous olefins and oxygenates comprising at least a unit (1) for supplying methanol and/or other oxygenates and olefin-containing feedstock, a unit (2) for supplying raw hydrocarbon fractions, a unit for supplying flows to be treated into a reactor, and a reactor (6) having at least a reaction zone with a zeolite-containing catalyst and an outlet for subsequent separation of the conversion product characterized in that a reactor (6) is further provided with at least one other reaction zone (62), and the unit for supplying flows into the reactor is adapted to supply the separate and/or pre-mixed flow of methanol and/or other oxygenates and olefin-containing feedstock and the flow of raw hydrocarbon fractions to the first reaction zone (61), and the flow of methanol and/or other oxygenates and olefin-containing feedstock to the second reaction zone (62), wherein between the reaction zones, there is further located means for mixing the reaction products from the upstream reaction zone and supplied methanol and/or other oxygenates and olefin-containing feedstock.
23. A plant of claim 22 characterized in that the unit for supplying flows is used, which contains a unit (5) for heating hydrocarbon feedstock and oxygenates, which has at least two outputs, the first of which is connected to the first input of the first reaction zone (61) directly or through the mixing zone, the second input of which is connected to the output of a unit (2) for supplying raw hydrocarbon fractions, wherein through the second output of the unit (5) there is supplied a flow of methanol and/or other oxygenates and olefin-containing feedstock to the second reaction zone (62).
24. A plant of claim 22 characterized in that it uses a unit for supplying flows comprising a unit (5) for heating the hydrocarbon feedstock and oxygenates, having at least one output connected to the input into the second reaction zone (62) directly or through the mixing zone comprising means for mixing located between the reaction zones, and a unit (3) for mixing the starting components, whose output is connected to the input to the first reaction zone (61), directly or through an additional heating unit (4).
25. A plant of claim 22 characterized in that the unit for supplying flows contains an additional unit (4) for heating having the input connected to the output of the unit (2) for supplying raw hydrocarbon fraction, and the output connected to the input to the first reaction zone (61).
26-35. (canceled)
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0132] Other features and advantages of the invention clearly emerge from the description that is given below for illustration and is non-limiting, with reference to the accompanying drawings, where:
[0133]
[0134]
[0135]
[0136] According to
[0137] The reactor 6 is made as a multiple-shell reactor that includes reaction zones on each shelf/catalyst basket or as a horizontal reactor, the housing of which accommodates several series-connected catalyst baskets. Either every reaction zone, or part of the reaction zones may be made as individual thermally insulated vessels.
[0138] The unit 1 for supplying methanol and/or other oxygenates and/or olefin-containing feedstock is connected to the unit 5 for heating the unit for supplying flows. The unit 5 may have at least one or at least two outputs.
[0139] In case of at least one outlet (not shown in the drawings), said output is connected to the input to the second reaction zone 62 either directly or through the mixing zone having means for mixing located between the reaction zones, wherein the unit for supplying also contains a unit 3 for mixing the starting components, whose output is connected to the inlet to the first reaction zone 61 either directly or through the heating unit 4. In the proposed embodiment, the downstream (second) output of the unit 5 may also be connected to the inlet to the first reaction zone 61 (
[0140] In case of at least two outputs (
[0141] The separation unit 7 is connected to gasoline stabilization column 9, wherein the bottom product is stabilized gasoline with improved antiknock rating. Other products of the column are gasoline stabilization gases and reaction water trapped out of the column reflux tank.
[0142] Upstream the reaction zones, the plant further includes a mixing device installed for mixing the reaction products from the upstream reaction zone and supplied methanol and/or other oxygenates and/or olefin-containing feedstock. The mixing device is not shown in
[0143] In one of the embodiments, a mixer for mixing the reaction products from the upstream reaction zones and supplied methanol and/or other oxygenates and/or olefin-containing feedstock is made as a bed of granules of neutral material and/or a fraction of crushed quartz placed upstream the front catalyst bed, and a line connecting the reaction zones is used as a mixing device.
[0144] The plant further may include devices for heating the reaction mixture installed upstream the last or the penultimate and last reaction zones; the diagram of
[0145] The last one or two reaction zones of the reactor can be made as isothermal reactors.
[0146] The plant further includes a unit 10 for determining the parameters of the resulting gasoline, such as RON, connected to a unit 11 controlling the flow rate of methanol and/or other oxygenates and/or olefin-containing feedstock in the unit 1 for supplying methanol and/or other oxygenates and/or olefin-containing feedstock.
[0147] The plant further includes a reaction water distillation column 8, the bottom product of which is water cleaned of residues of hydrocarbons with a reduced content of methanol and/or other oxygenates, and the distillate of which is water with an increased content of methanol and/or other oxygenates and hydrocarbons.
[0148] The output of the conversion product separation unit for removal of the reaction water with an admixture of methanol can be connected to the input of the rectification column 8, wherein the output of the distillation column with distillate is connected to the input of the unit 1 for supplying methanol and/or other oxygenates and/or olefin-containing feedstock.
EMBODIMENT OF THE INVENTION
[0149] The gasoline base of raw hydrocarbon fractions, fractions of the gaseous olefins and oxygenates is produced as follows (see
[0150] Step A1. In the unit 3, starting components are mixed, which are supplied through the unit 1 for supplying methanol and/or other oxygenates and/or olefin-containing feedstock, and the unit 2 for supplying raw hydrocarbon fractions.
[0151] Step A2. The starting feedstock is heated in the unit 4 for heating the starting feedstock. During heating, if necessary, the heavy components are separated.
[0152] Step A3. The mixture is supplied from the unit 4 to the reactor 6, wherein the reaction is carried out in the presence of a zeolite-containing catalyst. The reactor contains at least two reaction zones, where the zeolite-containing catalyst is located. The mixture from step A2 is supplied into the first reaction zone 61. After heating in the unit 5, methanol and/or other oxygenates and/or olefin-containing feedstock are divided into several flows, the first flow is mixed with the converted hydrocarbon feedstock from the first reaction zone 61 in the mixing zone between the first and second reaction zones, and the subsequent flows are mixed in the downstream mixing zones (not shown in the drawings) with the conversion product from the upstream reaction zone.
[0153] A bed of granules of a neutral material and/or a fraction of crushed quartz placed upstream the catalyst bed placed on a shelf, or a line connecting the reaction zones are used as a mixing zone (a mixing device).
[0154] Methanol and/or other oxygenates are supplied in the gaseous phase at a temperature of no more than 380° C. preventing its decomposition upon heating.
[0155] The isothermal reactors are used as the last or the last and the penultimate reaction zones of the reactor. Alternatively, the adiabatic reactors are used as the last or last and the penultimate reaction zones of the reactor.
[0156] Zeolite-containing catalysts are used in the reaction zones, whose binder is a mixture of alumina in an amount of 30-70 wt. % and silica in an amount of 70-30 wt.
[0157] Alternatively, the catalyst is used for production of liquid hydrocarbons of dimethyl ether based on crystalline pentasil-type aluminosilicate having a molar ratio of SiO.sub.2/Al.sub.2O.sub.3=25-100 characterized by the presence of residual amounts of sodium ions equivalent to a content of 0.05-0.1% wt. of sodium oxide containing said crystalline aluminosilicate and binder, wherein it further contains cobalt oxide, oxides of rare earth elements and zinc oxide at the following component ratio, wt. %:
[0158] Zinc oxide: 0.5-3.0
[0159] Oxides of rare earth elements: 0.1-5.0
[0160] Cobalt oxide: 0.05-2.5
[0161] Crystalline aluminosilicate: 63-69.8
[0162] Binder: the rest.
Alternatively, the catalyst of light aliphatic hydrocarbon conversion is used characterized in that a mixture of pentasil group zeolites with a different silicate module is used as the HZSM-5 zeolite: 1) zeolite with SiO.sub.2/Al.sub.2O.sub.3=20 previously treated with an aqueous solution of alkali, modified with oxides of rare earth elements (REE) in an amount of 0.5-2.0 wt. %, and 2) zeolite with SiO.sub.2/Al.sub.2O.sub.3=82 with a residual amount of sodium oxide in an amount of 0.04 wt. % taken in a ratio of 1.7/1 to 2.8/1, and the remainder being a binder in an amount of 20 to 30 wt. % of the catalyst.
[0163] Step A4. The flow rate of methanol and/or other oxygenates and/or olefin-containing feedstock into the reaction zones is controlled (by the unit 1 and through picking methanol and/or other oxygenates and/or olefin-containing feedstock into the reaction zone from the unit 5), and the temperature of the mixture supplied to the first reaction zone (by the unit 4) is controlled so that the maximum temperature of the catalyst bed does not exceed 420° C. in the preparation of the base stock for the production of high-octane gasoline and 500° C. for the production of a concentrate alkylaromatics, and the temperature of the end catalyst bed in the reaction zone is respectively by 40-70° C. below the maximum temperature of the bed. If methanol is supplied in an amount of less than 20 to 25 wt. %, additional heat supply to the downstream reaction zones is required. To supply heat, hot stabilization gases from the fractionation unit 9 or heated circulating exhaust gases from the unit 7 can be used, or a heater can be installed on the line connecting 2 last zones, or heat is supplied using the heat pipes, or otherwise, or heat supply can be carried out through heating, e.g., preferably superheating the flow supplied into the last or the last and the penultimate reaction zones, but no more than up to 500° C., or isothermal reaction zones with heat exchanging heat supply can be used as the last or the last and the penultimate reaction zones.
[0164] Step A5. The temperature of the last or the last and the penultimate reaction zones is decreased during catalyst operation each time by 1-2° C. as the allowable concentration of methanol in the reaction water increases.
[0165] Step A6. A 1-2% aqueous solution of an industrial demulsifier is added to a mixture of hydrocarbons and water supplied to the separation at a ratio of 1:100 1:200 to the volume of the reaction water. Here, the aqueous solution of the demulsifier is mixed with the input flow in a laminar static mixer or directly in a condenser of hydrocarbons and reaction water located in the separation unit 6 upstream a three-phase separator.
[0166] Step A7. Gasoline is isolated by the separation of the conversion product while diverting simultaneously the reaction water and exhaust gases.
[0167] In the unit 7, the reaction mixture is cooled with partial condensation of C.sub.5+ hydrocarbons and the aqueous portion, further, the three-phase separator located in the same location separates the mixture into the gaseous phase, hydrocarbon condensate and reaction water. The separated hydrocarbon condensate is supplied to a distillation unit 9, from where gasoline selected by stabilized vapor pressure and dried is picked up, and stabilization gases and reaction water with a high content of methanol are picked up from the reflux tank. The separated reaction water with an admixture of methanol and/or other oxygenates is supplied to the distillation unit 8, the distillation residue of which is water cleaned of residues of hydrocarbons with a reduced content of methanol and/or other oxygenates, and the distillate of which is water with a higher content of methanol and/or other oxygenates and hydrocarbons, wherein water with an increased content of oxygenates and hydrocarbons produced in the rectification process are recycled to the reactor inlet to the beginning of the process in a mixture with methanol and/or other oxygenate and/or olefin-containing feedstock.
[0168] Step A8. If the parameters of the produced gasoline with improved antiknock rating differ from the specified parameters that are measured by the unit 10 for determining the parameters of the resulting gasoline, the flow rate of methanol and/or other oxygenates and/or olefin-containing feedstock to the reactor is increased or decreased by the unit 11 controlling the flow rate of methanol and/or other oxygenates and/or olefin-containing feedstock.
[0169] The sequence of steps is exemplary and allows rearranging, adding or making some operations simultaneously without losing the ability of the production of a base stock for the production of gasolines from raw hydrocarbon fractions, fractions of gaseous olefins and oxygenates.
INDUSTRIAL APPLICABILITY
[0170] The proposed plant for producing gasolines from raw hydrocarbon fractions can be embodied in practice, and upon embodiment, it provides an implementation of the declared application, which allows making a conclusion that the invention complies with the “industrial applicability” criterion.
[0171] In accordance with the proposed invention, tests and calculations for the production of gasolines from various hydrocarbon fractions, fractions of gaseous olefins and oxygenates have been conducted.
Example No. 1. Modeling the First Reaction Zone
[0172] A zeolite catalyst was used for the conversion of dimethyl ether after regeneration.
[0173] The process was carried out at atmospheric pressure in a reactor having a useful volume of about 1.5 liters and with thermal insulation made as an air gap between the external surface of the cylindrical reactor shell and an outer protection casing, and with compensation of heat losses using external heating of the protective casing. Previously, the catalyst bed having a volume of 1.2 liters (855 g) was heated to a temperature of 350° C. A mixture of the following mass composition was supplied on the catalyst bed at a temperature of 335° C.: [0174] Methanol: 6.6% [0175] Water: 7%, [0176] Ethylene: 2.9%, and [0177] Straight-run hydrocarbon fraction: 65-85° C., 83.4%, with the composition given in Table 3.
[0178] The mass feedstock flow rate was 2.6 kg/L of catalyst h.sup.−1. During steady state, the temperature of heating of the adiabatic catalyst bed in a narrow front bed (no more than one quarter of the charged catalyst) was about 60-65° C. (from 335° C. to 395-398° C.)), the end catalyst bed temperature was about 360° C. The mass yield of the C.sub.5+ fraction from the first reaction zone was 97.5% per the hydrocarbon fraction supplied (65-85° C.). RON for the C.sub.5+ hydrocarbons fraction to be released from the conversion products was 67 units with RON of the initial fraction equal to 58 units. The methanol conversion was 99.9%.
Example No. 2. Increase in RON of the Product by Increasing the Methanol Flow Rate
[0179] It differs from the Example No. 1 by that the temperature of the raw mixture was reduced down to 320° C. A mixture of the following mass composition was supplied to the reactor inlet: [0180] Methanol: 10.7% [0181] Water: 3.4% [0182] Ethylene 2.6%, and [0183] Fraction, 65-85° C.: 83.4% the rest.
[0184] The mass feedstock flow rate was 2.6 kg/L of catalyst h.sup.−1. During steady state, the temperature of heating of the adiabatic catalyst bed in a narrow front bed (less than one quarter of the charged catalyst) was about 80-85° C. (from 320° C. to 402-406° C.)), the end catalyst bed temperature was about 365° C. The mass yield of the C.sub.5+ fraction from the first reaction zone was 96.4% per the hydrocarbon fraction supplied (65-85° C.). RON for the C.sub.5+ hydrocarbons fraction to be released from the conversion products was 71 units with RON of the initial fraction equal to 58 units. The methanol conversion was 99.5%.
Example No. 3
[0185] We used the same catalyst as that used in experiment 1. A flow reactor was used, wherein the catalyst was filled for the conversion of light hydrocarbons and oxygenates to aromatics concentrate in three beds in an amount of 18 ml of the catalyst each (a total amount of 40 g of catalyst). The catalyst beds were separated by quartz chip beds in an amount of 36 ml each forming the zones for mixing and heating the hydrocarbon feedstock. A narrow straight-run gasoline fraction at 65-85° C. having a density of 0.71 at a flow rate of 60 ml/hr and 80 wt. % methanol at a flow rate of 12 ml/hr were supplied to the first reaction zone.
[0186] Additionally, 80 wt. % methanol was supplied through the capillaries at a rate of 6 ml/hr to the second and third reaction zones through the mixing zones. The ratio of methanol/straight-run fraction was equal to 0.38.
[0187] Temperature in the reaction zones: 365-380° C.
[0188] Reactor pressure: 0.3-0.35 MPa.
[0189] Material balance of experiment as of the 4.sup.th hour of the experiment is given in the Table below.
TABLE-US-00001 TABLE 1 Supplied g/hr to the first reaction zone Fraction 65-85° C. (RON 58) 42.7 Methanol 8.13 Water 2.03 To the second reaction zone additionally Methanol 4.065 Water 1.01 To the third reaction zone additionally Methanol 4.06 Water 1.015 Total supplied 62.98 Produced Liquid fraction of hydrocarbons (RON 87.5) 41.8 Reaction water 13.21 Hydrocarbon hydrogen-containing gas having a 7.97 propane content of up to 39 wt. % Conversion of methanol 99.7% C.sub.5+ hydrocarbon yield per gasoline supplied 0.975
Example No. 4 (Comparative)
[0190] A flow reactor was loaded with 36 ml (26.7 g) of the catalyst, where a narrow straight-run gasoline fraction at 65-85° C. having a density of 0.711, at a flow rate of 36 ml/hr and 100 wt. % methanol at a flow rate of 12 ml/hr were supplied.
[0191] The ratio of methanol/straight fraction was equal to 0.371.
[0192] The temperature in the reaction zone was 365-380° C.
[0193] The reactor pressure was 0.3-0.35 MPa.
[0194] The material balance as of the 4.sup.th hour of the experiment is shown in Table 2.
TABLE-US-00002 TABLE 2 Supplied g/hr Fraction at 65-85° C. (RON 58) 25.60 Methanol 9.50 Total supplied 35.10 Produced Liquid fraction of hydrocarbons (RON 86.3) 24.79 Reaction water 5.34 Hydrocarbon hydrogen-containing gas having a 4.97 propane content of up to 42 wt. % Conversion of methanol 100% C.sub.5+ hydrocarbon yield per gasoline supplied 0.968
[0195] Table 3 shows a comparison of the compositions in weight percentage of the initial narrow straight-run fraction C.sub.6-C.sub.7, and C.sub.5+ hydrocarbon fraction from the catalysate hydrocarbon condensate. As seen from the comparison of examples when using a reactor with three reaction zones and with the distributed supply of methanol, the benzene and durene content in gasoline reduced, the content of alkylaromatics increased.
TABLE-US-00003 TABLE 3 C.sub.5+ fraction C.sub.5+ fraction from from catalysate hydrocarbon hydrocarbon condensate, Feedstock condensate, Example 3 (fraction at Example 4 (reactor with 3 Component description 65-85° C.) (comparative) reaction zones) C.sub.5-C.sub.6 olefins 0.20% 0.32% Sum of C.sub.6-C.sub.8 five- 9.26% 8.18% 8.40% membered naphthenes Sum of C.sub.6-C.sub.8 six 5.97% 3.79% 2.82% membered naphthenes Isopentane 0.00% 3.91% 4.22% Sum of C.sub.6 isoparaffins 0.49% 1.03% 1.16% with two branches Sum of C.sub.7 isoparaffins 29.33% 22.18% 20.51% with two branches Sum of C.sub.6 isoparaffins 9.34% 11.26% 11.53% with one side branch Sum of C.sub.7 isoparaffins 15.69% 6.04% 6.38% with one side branch n-pentane 3.44% 3.78% n-hexane 20.93% 9.71% 9.52% n-heptane 6.57% 1.66% 1.51% Benzene 1.53% 1.12% 0.76% Toluene 0.90% 5.29% 4.55% Xylenes and ethylben- 11.31% 12.69% zene C.sub.9 aromatics 6.79% 7.55% C.sub.10 aromatics 3.10% 2.85% A.sub.11+ 1.12% 1.45% Total 100% 100% 100% Including aromatics 2.4% 28.70% 30.10% Including sum of tetra- 1.20% 0.93% methylbenzenes Of these, 0.46% 0.30% durene (1,2,4,5- tetramethylbenzene)
Example No. 5
[0196] This example demonstrates the possibility of using feedstock containing diene and triene hydrocarbons, as well as the ability to control the degree of conversion of feedstock by increasing the maximum process temperature.
[0197] A catalyst of conversion of light aliphatic hydrocarbons was used.
[0198] The feedstock was a mixture consisting of a mixture of SNG (stable natural gasoline) in an amount of 50 vol. % and a light fraction (initial boiling point: 120° C.) of catalytic cracking gasoline from Ufa Refinery. The total sulfur content in the mixture fraction was 0.008 wt. %. The content of diene and triene hydrocarbons was 0.3 wt. Into a flow reactor, 100 ml. (74 g) of fresh catalyst was loaded. During the experiment, to maintain RON at a level of about 92 units the volumetric feedstock flow rate was reduced by 20%, and the maximum temperature in the reaction zone was increased from 380 to 390° C.
[0199] Table 4 shows the material balance of the experiment corresponding to the 203.sup.rd hour of the pilot plant operation. Diene and triene hydrocarbons were not detected in the produced gasoline. The total sulfur content was reduced to 0.001 wt. %. The methanol conversion during the experiment was no less than 99% and was adjusted by increasing the temperature in the reaction zone and reducing the feedstock volumetric flow rate.
TABLE-US-00004 TABLE 4 Supplied g/hr Mixture of 50% of SNG and light fraction catalytic 50.47 cracking gasoline (initial boiling point: 120° C.). Methanol 23.73 Total supplied 74.20 Produced Liquid fraction of hydrocarbons (RON 92) 44.90 Reaction water 13.39 Hydrocarbon hydrogen-containing gas having a propane 15.9 content of up to 55 wt. % Methanol conversion 100%
Example No. 6 (Calculated)
[0200] The content of methanol in the reaction water is 1.3 wt. %.
[0201] The reaction water is supplied into an evaporator with a vapor space where it is evaporated at a pressure close to atmospheric pressure. Vapors of the reaction water are supplied to a column still. The number of fractionating trays in the column is ten. Vapors from the top of the column are condensed and supplied partially as reflux to the column for reflux. The yield of distillate is 11 wt. % of the weight of the starting feedstock supplied to the column as vapor. The concentration of methanol in the distillate is 8-9 wt. %. This product is admixed to 100 wt. % methanol supplied for conversion together with the hydrocarbon feedstock. As a result, methanol at a concentration of 94 wt. % is supplied for conversion. The bottom product of the column is desalted and water cleaned of hydrocarbons, with the methanol content of no more than 0.2 wt. %.
[0202] Thus, as a result of measurement and calculations, it has been found that the separation of methanol and/or other oxygenates and/or olefin-containing feedstock into multiple flows according to the invention with simultaneous utilization of a reactor comprising at least two reaction zones, allows increasing the useful reactor volume, simplify its design, and besides reduce gassing, reduce the consumption of methanol per unit of increment of RON of the base stock for the production of gasolines.
[0203] Accordingly, the present invention achieves the task set, i.e. increasing the quality of the produced high-octane gasoline due to the reduction of the content of benzene in gasoline, as well as the content of high melting point components such as durene, as well as due to the possibility of regulating the temperature throughout the catalyst bed without using complicated heat-exchange reactor equipment, as well as the possibility of increasing the useful volume of reactor equipment.
[0204] An additional advantage of the proposed solution is that: [0205] There is a low content of C.sub.1-C.sub.2 hydrocarbons in exhaust gases, and since hydrogen is substantially insoluble in liquid hydrocarbons, this allows producing hydrogen-containing gas by using the C.sub.3+ hydrocarbon absorption from exhaust gases with debutanized gasoline from the discussed plant. [0206] Instead of a factory gas fractioning plant, an absorption column can be used, into which gasoline is supplied that has been produced in the plant and cooled down to a temperature range of −10° C. to +15° C. Saturated gasoline is supplied from this column to the stabilization column (unit 9). This increases the yield of commercial propane-butane mixture (C.sub.3-C.sub.4) and allows producing hydrogen-containing gas with a low hydrocarbon content. [0207] As feedstock for the production of gasoline, instead of straight-run gasoline or in conjunction with it, there can be used side-cut fractions from various processes, including fractions containing benzene and so on, fractions containing diene hydrocarbons, including light catalytic cracking gasolines. [0208] Sulfur content in co-processed gasoline is 5-20 times lower than that in the original gasoline. This is because the catalyst runs on feedstock having a sulfur content in convertible gasoline of up to 500 ppm by weight. Sulfur is mainly trapped out as hydrogen sulfide along with exhaust gases and is partly sorbed on the catalyst and is removed during regeneration.
[0209] Gasolines produced in the processing by their basic characteristics (group composition, RON, sulfur content, etc.) comply completely with the fifth grade gasoline characteristics in terms of technical regulations under the Customs Union (CU TR 013/2011) “On requirements for automobile and aviation gasoline, diesel and marine fuel, jet fuel and heating oil”.
[0210] The various embodiments of feedstocks, materials, processes, methods, equipment, and systems, set forth in this specification may be used may be used with each other in different and various combinations. Thus, for example, the configurations provided in the various embodiments of this specification may be used with each other; and the scope of protection afforded the present inventions should not be limited to a particular embodiment, configuration or arrangement that is set forth in a particular embodiment, example, or in an embodiment in a particular Figure.
[0211] Although the present invention has been described in detail by exemplary embodiments, which appear to be preferred ones, it should be remembered that these embodiments are given only for the purpose of illustrating the invention. This description should not be construed as limiting the scope of the invention, since the steps of the described methods and plants may be amended by experts in the field of oil, petrochemicals, physics, etc. in order to adapt them to specific plants or situations, and not leaving the scope of the appended claims. Those skilled in the art will understand that within the scope of the invention as defined by the claims, various variations and modifications, including equivalent solutions, are possible.