WO2022005333A1

WO2022005333A1 - Method for increasing the yield of a liquid hydrocarbon product

Info

Publication number: WO2022005333A1
Application number: PCT/RU2021/050179
Authority: WO
Inventors: Владимир Владиславович ИМШЕНЕЦКИЙ; Иосиф Израилевич ЛИЩИНЕР; Ольга Васильевна МАЛОВА; Денис Васильевич ПЧЕЛИНЦЕВ; Андрей Леонидович ТАРАСОВ; Александр Анатольевич БЕССОНОВ; Дмитрий Валерьевич ИВАНОВ; Елена Николаевна ЛОБИЧЕНКО
Original assignee: Общество С Ограниченной Ответственностью "Новые Газовые Технологии-Синтез"; Акционерное общество "Газпромнефть-Омский НПЗ"
Priority date: 2020-06-29
Filing date: 2021-06-22
Publication date: 2022-01-06
Also published as: CU20220075A7; RU2747866C1

Abstract

The invention relates to a method for producing gasolines, in which four streams of feedstock are used, the first stream containing a hydrocarbon fraction, the second stream containing an oxygenate, the third stream containing a first olefin-containing fraction, and the fourth stream containing a second olefin-containing fraction, wherein the first olefin-containing fraction includes 10-50 wt% С₂-С₄ olefins and 0.5-8.0 wt% hydrogen, and the second olefin-containing fraction includes 50-70 wt% C₃-C₄ olefins and from 0 to 5.0 wt% С₁-С₂ hydrocarbons, and in which three reaction zones are used which are filled with a zeolite catalyst, wherein the second stream is fed into the first, second and third reaction zones, the mass fraction of the second stream fed into each subsequent reaction zone being less than the mass fraction of the second stream distributed into each preceding reaction zone, and each of the other three streams is fed into at least one reaction zone. The method makes it possible to produce gasolines using low-demand olefin-containing fractions, such as dry gas from catalytic cracking, a propane-propylene fraction or a butane-butylene fraction, and to increase the octane rating of the product to 95-98 at a product yield of more than 70 wt%, while also reducing the diesel fraction content to less than 2 wt%.

Description

METHOD FOR INCREASING THE OUTPUT OF LIQUID HYDROCARBON

PRODUCT

The invention relates to the field of oil refining and petrochemical industries. More specifically, the invention relates to a method for the production of gasolines by co-processing of hydrocarbon fractions, oxygenates and olefin-containing fractions.

The following terms are used in the description:

Gasoline - commercial gasoline or the main component (base) for the production of gasoline. In particular, gasoline obtained by the proposed method can be used to obtain motor gasolines by compounding methods (mixing gasoline fractions obtained by various oil refining processes). For example, according to the proposed method, a basis for the production of motor gasoline of ecological class K5 of the AI-95 brand according to GOST 32513-2013 can be produced. In some cases, the gasoline obtained by the proposed method may not meet all the requirements for commercial gasoline by this or that region or organization. For example, the end-boiling point of gasoline may exceed 215 ^° C. As another example, the benzene content of produced gasoline may exceed 1.0 vol. %. As another example, the aromatic content of the gasoline produced can exceed 35 vol. %. In particular, the produced gasoline can contain from 20 to 98 May. % aromatics, preferably from 25 to 60 May. % aromatics. As gasoline can be considered a liquid hydrocarbon product produced by the proposed method. Produced by the proposed method, liquid hydrocarbon products with an aromatic concentration above 40 May. % can be successfully used as a high-octane base for the production of motor gasolines.

Hydrocarbon fraction - a fraction of the gasoline boiling range (the boiling point is not standardized, the boiling point is not more than 215 ° C). In particular, the end of the boiling point can be 200 ° C, 180 ° C, 160 ° C or 85 ° C. Preferably, the end boiling point is not higher than 180 ° C. The onset of boiling can be, for example, 62 ° C, 85 ° C, 140 ° C. Preferably, the initial boiling point is at least 62 ° C.

Oxygenate is an aliphatic alcohol or ether. It can be selected from the group including: methanol, raw methanol, technical methanol, ethanol, dimethyl ether, other aliphatic alcohols, other ethers, as well as mixtures thereof, incl. with water. May contain impurities such as aldehydes, carboxylic acids, esters, aromatic alcohols. The method does not involve the use of unsaturated (unsaturated) alcohols, for example, allyl alcohol, but their presence is possible as impurities.

Olefin-containing fraction Ci + (first olefin-containing fraction) - a fraction including 10-50 May. % olefins C ₂ -C ₄ (ethylene, propylene, normal butylenes, isobutylene) and 0.5-8.0 wt. % hydrogen.

The olefin-containing fraction Ci + may contain inert or weakly reactive components other than olefins, for example: methane, ethane, propane, butane, hydrogen, nitrogen. For example, the first olefin-containing fraction may contain from 0.5 to 8.0 wt. % hydrogen, preferably from 2 to 8 May. % hydrogen. Preferably, the mass fraction of C ₅₊ hydrocarbons in the olefin-containing Ci + fraction is not more than 5.0 wt. %. Preferably, the volume fraction of hydrogen sulfide in the olefin-containing fraction Ci + is not more than 0.005%.

The presence of the index "C1 ₊ " in the term "olefin-containing fraction Ci ₊ " indicates the possibility of the presence of methane in the first olefin-containing fraction. However, cases are possible when the first olefin-containing fraction does not contain Ci hydrocarbons (methane content 0.0 wt%).

Olefin-containing fraction C3-C4 (second olefin-containing fraction) - a fraction including 50-70 May. % of C ₃ -C ₄ olefins (propylene, butylenes, isobutylene) and no more than 5.0 May. % C ₁ -C ₂ hydrocarbons (methane, ethane, ethylene).

The olefin-containing C ₃ -C ₄ fraction may contain inert or weakly reactive components other than olefins, for example: propane, butane, isobutane, pentane, isopentanes, hydrogen, nitrogen.

The reaction zone is a separate volume in the reactor containing the catalyst. Several consecutive reaction zones can be located in one reactor. For example, the reaction zones can be shelves in a shelf reactor. Also, each reaction zone can be located in a separate reactor. A separate reactor can be used as the reaction zone.

OCHI is a research octane number. It can be determined, for example, according to ASTM D2699 or according to GOST 8226.

C _{n -} hydrocarbons with the number of carbon atoms n.

Cn + - hydrocarbons with the number of carbon atoms equal to or more than n.

REE - rare earth elements.

DME stands for dimethyl ether.

SGKK is a dry catalytic cracking gas.

FAU - fraction of aromatic hydrocarbons. Diesel fraction - a hydrocarbon fraction with a boiling point range of 220-350 ° C, i.e. the initial boiling point is not less than 220 ° С, the final boiling point is not more than 350 ° С.

PPF - propane-propylene fraction.

BBF - butane-butylene fraction.

Mass feed rate of raw materials, h ¹ - the amount of raw materials passed per unit time through a unit mass of the catalyst. For example, the mass feed rate

1st component:

where 1 ^X0 is the mass flow of the i-ro component at the inlet, g / h. m _{cat is the} mass of the catalyst, g.

Conversion is the ratio of the amount of raw material that has entered the reaction to the amount of raw material fed into the reaction. For example, the conversion of the i-ro component:

where / _£ ^input is the mass flow of the i-ro component at the input, g / h. mass flow of the i-ro component at the outlet, g / h.

Selectivity is the ratio of the amount of the target component to the total amount of hydrocarbons obtained in the given process. For example, the selectivity of the i-ro component of the product: yield

Si = n

where ^g . ^output mass flow of the i-ro component at the output, g / h,

- total mass flow of all produced hydrocarbons, g / h.

The percentage of oxygenate substitution for olefin-containing fractions (% substitution) is calculated as follows:

S; fct - oxygenate

% substitution = - 100%, lk - u about (4)

xigenate S ^ ^' D / olefin) where u _oxygenate is the molar flow i-ro of the supplied oxygenate, mol / h, k, is the coefficient advising the i-th supplied oxygenate. The k factor is 0.5 for methanol, 1 for other oxygenates (eg ethanol, propanol, DME). r _{j olefin} - molar flow of the j -th fed olefin, mol / h. For example, when methanol is used as oxygenate, the first olefin-containing fraction includes propylene and the second olefin-containing fraction includes propylene, the percentage of substitution is calculated as follows:

0.5 p methanol

% substitution = 1 - - - - 100%, 0.5 · "-methanol 4 ^" ^ -propylene_1 4 ^" ^ -propylene_2

(5) where “methanol, _mol / _{h is the} molar flow of methanol supplied, mol / h, ⁿ propylene_1 is the molar flow of propylene supplied as part of the first olefin-containing fraction, mol / h, ⁿ propylene_2 is the molar flow of propylene supplied as part of the second olefin-containing fraction, mol / h,

0.5 is the coefficient corresponding to methanol.

As another example, if ethanol is used as oxygenate, the first olefin-containing fraction contains ethylene and the second olefin-containing fraction contains propylene and butylenes, the substitution percentage is calculated as follows.

% replacement

where n _Ethanol ^_ molar flow of supplied methanol, mol / h, n _EtIlene ^_ molar flow of supplied ethylene, mol / h,

" _Propylene ^_ molar flow of propylene feed, mol / h,

"Butylenes - total molar flow of supplied butylenes (including isobutylene), mol / h,

1 - coefficient for ethanol.

LEVEL OF TECHNOLOGY

There are several examples of joint processing of hydrocarbon fractions, oxygenates and olefin-containing fractions into gasolines.

Patent RU 2671568 dated 09/27/2016 refers to a complex installation for processing a mixture of Ci-Cio hydrocarbons of various compositions (low-octane gasoline fractions n.c.-180 ° C, 90-160 ° C or narrower fractions, pentane-heptane (hexane) fractions , propane-butane fractions, NGL and / or lower olefins Cr-Ciu and / or their mixtures with each other and / or with paraffins Ci-Cio, and / or with hydrogen) in the presence of oxygen-containing compounds, including one or more parallel sectioned adiabatic reactors, consisting of one or more stationary layers (sections) of a zeolite-containing catalyst with the supply or removal of heat between the layers (sections) of the catalyst. The proposed installation allows to obtain high-octane gasolines, diesel fractions or aromatic hydrocarbons.

The disadvantage of the invention is the need to add significant amounts of isobutane to the feedstock in order to control the temperature of the reaction zones. Isobutane is a highly demanded refinery product with a high cost. Its redirection to the processing of the hydrocarbon fraction will lead to an increase in the cost of gasoline production.

The disadvantage of the invention is also the circulation of a part of the gaseous product directly through the catalyst bed. Recycling the gaseous product complicates the required equipment and its maintenance. Also, this approach does not allow working with sulfur-containing raw materials without involving additional purification methods. In particular, the plant contains a unit for removing sulfur compounds using the hydrogen-containing gas obtained in the process from at least a portion of the hydrocarbon feedstock. Incomplete purification of raw materials from sulfur can lead to the production of a gaseous product contaminated with sulfur compounds. Recycling of such a gaseous product will lead to accelerated poisoning of the catalyst with gaseous sulfur-containing compounds (hydrogen sulfide, mercaptans).

Application for the invention WO2017155431 describes a method for producing gasolines from raw hydrocarbon fractions, fractions of gaseous olefins and oxygenates. As a reactor, a reactor is used containing at least two reaction zones with a zeolite-containing catalyst, between which there is additionally located means for mixing the reaction products of the previous reaction zone and supplied methanol or other oxygenates and olefin-containing raw materials, and through the unit for feeding streams:

• to the first reaction zone of the reactor: a stream of methanol or other oxygenates and olefin-containing raw materials and a stream of raw hydrocarbon fractions,

• to the second reaction zone of the reactor - a stream of methanol or other oxygenates and olefin-containing raw materials.

As a disadvantage of the method can be considered the fact that when obtaining gasoline, the temperature of the end layer of the catalyst is 40-70 ° C lower than the maximum temperature of the catalyst layer. Such a drop in temperature in the end layer of the catalyst can lead to uneven coking of the catalyst and to the occurrence of side reactions (for example, oligomerization of olefins instead of involving them in the processes of aromatic alkylation and aromatics formation). As a disadvantage of the method, the need for additional heat supply to the reaction zones can also be considered, then at low methanol consumption (less than 20% of the mass of the converted raw material), including due to additional overheating of the feed stream supplied to the last and / or penultimate reaction zones (maximum up to 500 ° C), or by using isothermal reaction zones as one or two of the last reaction zones of the reactor.

This method is the closest to the present invention and is taken as a prototype.

But none of the documents described does not investigate how the distribution of the oxygenate streams and the two olefin-containing fractions affect the process parameters. Also known documents do not take into account the problems that arise when replacing pure olefins with cheap sources of C2-C4 olefins. Conditions are not disclosed that allow obtaining a high-octane product under conditions when the feedstock includes methane, ethane, hydrogen, nitrogen. It is also not disclosed that the use of raw materials of a certain composition with an appropriate distribution between the reaction zones will eliminate the recycle of gaseous products.

DISCLOSURE OF THE INVENTION

The objective of the invention is to involve low-demand olefin-containing fractions in the production of high-octane gasolines while maintaining the yield and quality of the product. In this case, it is necessary to ensure the yield of a liquid hydrocarbon product above 70% for the supplied hydrocarbon fraction and the RON of the product above 95 units, preferably 95-98 units. Such a product is an attractive high-octane base for the production of commercial gasolines with octane numbers above 95 units.

The technical results of the present invention are also considered:

1. involvement in the production of high-octane gasolines of the olefin-containing fraction Ci ₊ , including hydrogen, without its additional separation;

2. Reducing the content of the diesel fraction in the product when the olefin-containing fraction C3-C4, including from 50 to 70 May, is involved in the production of gasoline. % of C3-C4 olefins;

3. Decrease in the content of olefins in the product to 1.1-3.0 May. %;

4. the ability to exclude the recycling of gaseous products;

5. absence of oxygenates in the liquid hydrocarbon product;

6. reduction of oxygenate consumption due to partial replacement of oxygenate with olefin-containing fractions. The solution to the problems and the achievement of the above technical results is achieved due to the proposed method for producing gasolines, in which four streams are used as raw materials, the first of which includes a hydrocarbon fraction, the second stream includes an oxygenate, the third stream includes the first olefin-containing fraction, the fourth stream includes the second olefin-containing fraction, and: a. the first olefin-containing fraction includes one or more olefins selected from the group consisting of: ethylene, propylene, butylenes, isobutylene, in a total amount of 10 to 50 May. % and includes 0.5-8.0 May. % hydrogen,

B. the second olefin-containing fraction comprises one or more olefins selected from the group consisting of propylene, butylenes, isobutylene, in a total amount of 50 to 70 May. % and includes from 0 to 5.0 May. % C1-C2 hydrocarbons, c. use three reaction zones filled with zeolite catalyst, d. the first stream is fed to at least one reaction zone, e. the second stream is fed into the first, second and third reaction zones, and the mass fraction of the second stream supplied to each subsequent reaction zone is less than the mass fraction of the second stream supplied to each previous reaction zone f. the third stream is fed to at least one reaction zone, g. the fourth stream is fed to at least one reaction zone. h. wherein the product stream from the first reaction zone is fed to the second reaction zone and the product stream from the second reaction zone is fed to the third reaction zone.

An embodiment of the invention is possible, in which the distribution of the second stream between the three reaction zones is 40-85 May. % / 10-35 May. % / 5-25 May. % of the total amount of the second stream.

In this case, the mass fraction of the second stream supplied to the first reaction zone is 40-85 May. % of the second stream, the mass fraction of the second stream supplied to the second reaction zone is 10-35 wt. % of the second stream, and the mass fraction of the second stream supplied to the third reaction zone is 5-25 May. % of the second stream.

An embodiment of the invention is possible in which the first stream is preferably fed to the first reaction zone. Possible execution of the invention, in which the hydrocarbon fraction contains normal paraffins in the amount of 15-24 May. %, isoparaffins in the amount of 42-56 May. %, naphthenes in the amount of May 22-40. %, the rest is aromatic hydrocarbons and olefins.

Possible execution of the invention, in which the hydrocarbon fraction contains from 0 to 80 May. % hydrocarbons C _b , preferably from 23 to 46 May. % C _b hydrocarbons, most preferably from 36 to 46 May. % hydrocarbons C _b .

Possible execution of the invention, in which the hydrocarbon fraction contains from 0 to 70 May. % C7 isoparaffins, preferably from 26 to 50 May. % C7 isoparaffins, most preferably from 26 to 38 May. % C7 isoparaffins.

It is possible to carry out the invention, in which the hydrocarbon fraction can be selected from the group including straight-run gasoline, stable gas gasoline, light gas condensate, gasoline fraction with boiling points of about 62 ° - 85 ° C, raffinate, and mixtures thereof.

An embodiment of the invention is possible, in which the first olefin-containing fraction is selected from the group consisting of dry catalytic cracking gas, catalytic cracking gas, off-gas from the coking unit, off-gas from the catalytic reforming unit, off-gases of the Fischer-Tropsch synthesis, pyrolysis gas, fuel gases of various origin, as well as mixtures thereof.

An embodiment of the invention is possible, in which the first olefin-containing fraction comprises 2.3-8.0 wt. % hydrogen, preferably 3.2-8.0 wt. % hydrogen.

An embodiment of the invention is possible, in which the mass fraction of C5 ₊ hydrocarbons in the first olefin-containing fraction is from 0 to 10.0 wt%. %, preferably from 0 to 5.0 May. %.

An embodiment of the invention is possible, in which the first olefin-containing fraction contains hydrocarbon components selected from the group: methane, ethane, propane, butane, and / or inorganic gases selected from the group: hydrogen, nitrogen, and / or impurities of heavier C5 _{+ olefins} , selected from the group: pentenes, hexene.

An embodiment of the invention is possible in which the second olefin-containing fraction is selected from the group consisting of propane-propylene fractions, butane-butylene fractions, catalytic cracking wet gas, and mixtures thereof.

It is possible to carry out the invention in which the oxygenate is selected from the group consisting of aliphatic alcohols and ethers, for example, methanol, ethanol, crude methanol, technical methanol, dimethyl ether, as well as mixtures thereof, including with water. It is possible to carry out the invention in which the oxygenate may contain impurities, for example, aldehydes, carboxylic acids, esters, unsaturated alcohols.

It is possible to carry out the invention, in which the zeolite catalyst comprises: a) a zeolite of the ZSM-5 type with a S1O2 / AI2O3 modulus from 43 to 95, in an amount from 65 to 80 May. %,

B) sodium oxide in an amount from 0.04 to 0.15 May. %, c) zinc oxide in the amount of 1.0-5.5 wt. %, d) oxides of rare earth elements in a total amount of 0.5-5.0 wt. %, e) a binder comprising silicon dioxide, aluminum oxide, or mixtures thereof.

An embodiment of the invention is possible in which the zeolite catalyst does not contain platinum metals.

It is possible to carry out the invention in which the rare earth elements are selected from the group including lanthanum, praseodymium, neodymium, cerium, as well as mixtures thereof.

An embodiment of the invention is possible, in which the mass feed rate of the raw material is 0.5-10 h ¹ , preferably 1-3 h ¹ .

An embodiment of the invention is possible, in which the process pressure is from 1.5 to 4.0 MPa, preferably from 2.2 to 2.7 MPa.

Possible execution of the invention, in which the hydrocarbon fraction is 70-83 May. % of the supplied raw materials.

An embodiment of the invention is possible, in which the first olefin-containing fraction is May 4-19. % of the supplied raw materials.

An embodiment of the invention is possible, in which the second olefin-containing fraction is 3-14 May. % of the supplied raw materials.

Possible execution of the invention, in which the temperature of the flow at the entrance to the first / second / third reaction zone is 350-380 ° C / 340-370 ° C / 340-370 ° C.

Possible implementation of the invention, in which the distribution of the catalyst on the reaction is 17-33 May. % / May 28-50. % / 33-50 May. % of the total amount of catalyst for the first / second / third reaction zone, respectively.

An embodiment of the invention is possible, in which the reaction is carried out in the gas phase in a fixed catalyst bed.

CARRYING OUT THE INVENTION

To carry out the process, the hydrocarbon fraction, oxygenate and olefin-containing fractions are separated into several streams. The streams are fed to the reaction zones:

R101 - the first reaction zone; R201 - second reaction zone;

R301 - third reaction zone.

The hydrocarbon fraction is fed to at least one reaction zone. For this, the hydrocarbon fraction can be separated into one, two or three streams. In particular, for carrying out the experiments of Examples 1-6, the entire hydrocarbon fraction was distributed to the first reaction zone (i.e., the second and third hydrocarbon fraction streams were not generated). To carry out the experiment according to example 7, the hydrocarbon fraction was distributed into three reaction zones (i.e., created the first, second and third streams of the hydrocarbon fraction). Also, if necessary, it is possible to distribute the entire flow of the hydrocarbon fraction only to the second or only to the third reaction zone. In another embodiment, the proposed process allows you to distribute the hydrocarbon fraction into several reaction zones.

The oxygenate is fed into the first, second and third reaction zones. For this, the oxygenate is divided into first, second and third oxygenate streams fed to the first, second and third reaction zones, respectively.

In this case, the mass feed rate of the third oxygenate stream, WHSV _{0X 3} , h ¹ , is less than the mass feed rate of the second oxygenate stream, WHSV _{0X 2} , h ¹ , and the mass feed rate of the second oxygenate stream, WHSV _{o 2} , h ¹ , is less, than the mass feed rate of the first oxygenate stream, WHSV _0X h ¹ , i.e. WHSV _0X s <WHSV _{0X 2} <WHSV _0X,.

As a result, the mass fraction of the oxygenate stream fed to each subsequent reaction zone is less than the mass fraction of the oxygenate stream fed to each previous reaction zone.

The first olefin-containing fraction is fed to at least one reaction zone. For this, the first olefin-containing fraction can be separated into one, two or three streams.

The second olefin-containing fraction is fed to at least one reaction zone. For this, the second olefin-containing fraction can be separated into one, two or three streams.

In the process, the product stream from the first reaction zone is fed to the second reaction zone and the product stream from the second reaction zone is fed to the third reaction zone.

In this case, each of the streams supplied to a specific reaction zone can be heated before or after mixing with other streams. Feed streams fed to a particular reaction zone are mixed in a mixing zone located upstream of the catalyst bed of that reaction zone. The mixing zone of the reaction zone can be, for example:

• a layer of granules of neutral material placed in front of the layer of zeolite catalyst, for example, a protective layer, forecontact;

• connecting line (main) connecting the reaction zones;

• a heater (or preheater) located between the reaction zones.

The product stream from the third reaction zone is separated into a hydrocarbon product fraction and an aqueous product fraction. The aqueous fraction of the product is withdrawn.

The hydrocarbon fraction of the product is then separated into a liquid hydrocarbon product and a gaseous product by means of fractionation and stabilization. In particular, settling and degassing of the aqueous phase, debutanization of the hydrocarbon phase, condensation of propane, etc. can be carried out. The gaseous product can be further separated into a gaseous product fraction enriched in C ₃ -C4 hydrocarbons and a gaseous product fraction enriched in C1-C2 hydrocarbons.

The main component of a liquid hydrocarbon product is C5 + hydrocarbons (hydrocarbons with five or more carbon atoms). Depending on the goals of a particular production, a liquid hydrocarbon product may contain not only C5 + hydrocarbons, but also different amounts of dissolved gases C1-C4. In particular, in the production of motor gasolines, it is usually allowed to be present until May 3-5. % of dissolved gases in summer gasolines and up to May 5-7. % of dissolved gases in winter gasolines. The gaseous product can include C1-C4 hydrocarbons, nitrogen, hydrogen and other inorganic gases, as well as heavier hydrocarbons.

Product streams can be directed to external heat exchangers, such as recuperative heat exchangers, to heat the feed streams and pre-cool the product streams.

Examples of

The results achieved are illustrated below in Examples 1-4 and 7, and Comparative Examples 5-6.

Comparative example 5 differs from the examples according to the invention in that no first olefin-containing fraction is fed to any reaction zone. Comparative example 6 differs from the examples according to the invention in that no second olefin-containing fraction is fed to either reaction zone. Example 7 repeats the conditions of Example 1, except that the distribution of the hydrocarbon fraction in the reaction zones is changed. In example 1, the distribution of the hydrocarbon fraction over the reaction zones Rioi / R201 / R301 was 100/0/0 May. %. Example 7 retains the same mass flow rates of raw materials as Example 1, however, the hydrocarbon fraction is distributed over the three reaction zones in a ratio of 50/30/20 May. %.

To carry out examples 1-7, a catalytic unit was used, including three reactors connected in series, with a total catalyst load of up to 9 liters. The reactors are designated as first, second and third reaction zones, R101, R201, and R301, respectively.

The reactors are structurally as close as possible to the adiabatic type, the heat exchange between the catalyst bed and the vessel is minimized. The catalyst baskets are placed in the reactor vessel so that a gap (approximately 2 mm) remains between the wall of the basket and the strong body. Each reactor is installed in a thermostat with three heating zones. Three thermocouples are placed between the surfaces of the heating elements and the outer surface of the reactor vessel. On the contrary, thermocouples are also located on the inner wall of the reactor basket casing. There is also an air gap not exceeding 3-4 mm between the inner surface of the thermostat and the outer surface of the reactor. The control loops maintain a constant temperature difference between the thermocouples at the outer wall of the reactor and the thermocouple opposite at the inner surface of the reactor basket.

Liquid and gaseous products for analysis began to be taken 4 hours after the start of the feed.

Table 1 shows the chemical compositions of the hydrocarbon fractions used in Examples 1-7. In particular, the 62-85 ° C fraction (fr. 62-85 ° C) is the benzene-forming part of the catalytic reforming feedstock (approximate boiling range 62-85 ° C). The raffinate is typically a mixture of predominantly gasoline-range hydrocarbons that have not been converted during the catalytic reforming process. The raffinate can be described as a by-product gasoline cut taken from an aromatic hydrocarbon extractive distillation unit. For example, the raffinate can be a by-product of the extractive distillation of the benzene-toluene fraction. Also, the raffinate can be a by-product of the extractive distillation of the toluene-xylene fraction.

Table 2 shows the compositions of the olefin-containing Ci ₊ fractions (first olefin-containing fraction) used in Examples 1-7. Used olefin containing Ci ₊ fractions can be considered, for example, as a model of a dry gas of catalytic cracking (the compositions of the SGCC were obtained as a result of averaging the data of the refinery over several months of operation of the catalytic cracking unit). Note, however, that the name and process of origin of the olefin-containing Ci ₊ fractions may vary depending on the enterprise and region. Attention should be paid to the chemical composition of the fraction used, in particular, the olefin-containing Ci ₊ fraction should include C ₂ -C ₄ olefins in a total amount of 10 to 50 May. %. The olefin-containing fraction may contain hydrogen in a concentration of 0.5 to 8 May. %, preferably from 2.3 to 8 May. % hydrogen, more preferably 3 to 8 May. % hydrogen. Preferably, the weight fraction of C ₅₊ hydrocarbons in the olefin-containing Ci ₊ fraction is not more than 5.0 wt%. %. Preferably, the volume fraction of hydrogen sulfide in the olefin-containing fraction Ci ₊ is not more than 0.005%.

Table 3 shows the compositions of the olefin-containing C ₃ -C ₄ fractions (second olefin-containing fraction) used in Examples 1-7. Used olefin-containing fractions C3-C4 can be considered, for example, as models of propane-propylene fraction, butene-butylene fraction and catalytic cracking wet gas. However, we note that the name and the process of origin of the olefin-containing fractions C3-C4 may vary depending on the enterprise and the region. Attention should be paid to the chemical composition of the fraction used, in particular, the olefin-containing C ₃ -C ₄ fraction should include C ₃ -C ₄ olefins in a total amount of 50 to 70 May. %, and contain no more than May 5. % C ₁ -C ₄ hydrocarbons (methane, ethane, ethylene).

Methanol technical grade "A" GOST 2222-95 was used as oxygenate in examples 1, 2, 5-7. Example 4 uses 95% ethanol. Example 3 used dimethyl ether (DME) 99%.

Table 4 shows the compositions of the zeolite catalysts used in Examples 1-7.

Table 5 shows the conditions and basic parameters of examples 1-6. The hydrocarbon fraction in examples 1-6 is fed to the first reaction zone. Example 7 repeats the conditions of Example 1, except that in Example 7 the hydrocarbon fraction is distributed over the three reaction zones in a ratio of 50/30/20 May. %. The experiments according to the invention were carried out at a pressure of 15-40 bar (1.5-4.0 MPa), preferably 22-27 bar (2.2-2.7 MPa). The parameter% oxygenate substitution (percentage of oxygenate substitution for olefin-containing fractions) is calculated using formulas (4) - (6) on pages 3-4 of this Description. Tables 6 and 7 show the compositions of the resulting liquid hydrocarbon product of Examples 1-6. Example 7 shows the yield of liquid hydrocarbon product C5 ₊ 78.9 wt. % on the supplied hydrocarbon fraction at the RON of the product 96.5 units. and an aromatics content of 48.5 May. % (data are given for a liquid hydrocarbon product that does not contain dissolved gases, similar to Table 6).

Table 7 shows the composition of gasoline after separation of gaseous products from it, while the content of dissolved gases in gasoline is stabilized at 3-5 May. % (stabilized liquid hydrocarbon product). Such a product can be considered as stable gasoline or as a high-octane base for the production of commercial gasolines. The foods in Table 7 contain from May 3 to May 5. % dissolved gases C1-C4. However, depending on the goals of a particular production, the liquid hydrocarbon product may contain different amounts of dissolved gases C1-C4. In particular, in the production of motor gasolines, it is usually allowed to be present until May 3-5. % of dissolved gases in summer gasolines and up to May 5-7. % of dissolved gases in winter gasolines. The desired amount of dissolved gases in the product is controlled by standard fractionation and stabilization techniques.

Table 6 shows the composition of the products for the same experiments as Table 7, however, Table 6 shows the composition of the liquid hydrocarbon products without dissolved gases C1-C4 (fraction C5 ₊ hydrocarbon fraction of the product). Typically, production does not require a product that does not contain dissolved gases. However, a comparison of the yield and composition of C5 ₊ products is more revealing. Liquid hydrocarbon products obtained and stored under different conditions may contain different amounts of dissolved gases. In this case, the content of dissolved gases can vary unevenly over time, changing the chemical composition. This can lead to inadequate comparison of the yield and quality of products from different experiments, especially when comparing results from different enterprises. Therefore, it is more preferable to compare the parameters of a product that does not contain dissolved gases. However, we note that, depending on the goals of a particular production, the liquid hydrocarbon product may contain not only С 5 ₊ hydrocarbons, but also different amounts of dissolved gases С1-С4, as shown in Table 7, for example.

Since C5 ₊ hydrocarbons (hydrocarbons with five or more carbon atoms) are the main component of a liquid hydrocarbon product, the yield of a liquid hydrocarbon product increases simultaneously with the yield of C5 ₊ hydrocarbons.

The gaseous product in examples 1-7 consisted mainly of saturated hydrocarbons and nitrogen. The source of nitrogen is the olefin- containing fractions. In examples 1-4 and 7, the content of C3 ₊ hydrocarbons (mainly propane) in the gaseous product was 30-67 vol. %. The total content of olefins in the gaseous product was 0.5-1.2 vol. %, which shows a high degree of conversion of feed olefins. The ethane content was 0.3-1.1 vol. %, which indicates the suppression of side processes of ethylene hydrogenation by hydrogen of the feedstock.

Table 1. Composition of hydrocarbon fractions, May. %

P (normal paraffins), I (isoparaffins), O (olefins), N (naphthenes), A (aromatics) ’The indicator serves to assess the composition of the fraction. Due to rounding to one and the presence of unrecognized components, it may not add up to 100.0%.

Straight-run gasoline, c.c. - the end of boiling is undefined.

^*** Isoparaffins with three or more chains (RON over 90) are contained in the used hydrocarbon fractions in trace amounts. Table 2. Composition of olefin-containing fractions Ci ₊ , May. % (first olefin-containing fraction)

Table 3. Composition of olefin-containing fractions Cs ₊ , May. % (second olefin-containing fraction)

Table 4. The composition of the zeolite catalysts used in examples 1-7.

* Rare earth elements (REEs) include, for example, lanthanum, praseodymium, neodymium, cerium, preferably mixtures thereof. The source of rare-earth compounds can be individual compounds of each of the elements, for example, nitrates. Mixtures of rare earth compounds can also serve as a source of rare earth compounds. For example, as a source of compounds of rare earth elements, intermediate products of the production of rare earth elements with a content of mixed compounds of rare earth elements of at least 60 May can be used. %, such as a concentrate of rare earth elements, rough rare earth concentrate of rare earth elements, collective concentrates of rare earth metals, intermediate products of processing of rare earth ores. Mixtures of rare earth compounds can be used without prior separation of the individual rare earth compounds.

Table 5. Conditions and basic parameters of examples 1-6.

^* In experiments 1-6, the entire hydrocarbon fraction is distributed to the first reaction zone. Table 6. Composition of the liquid hydrocarbon product that does not contain dissolved gases.

P (normal paraffins), I (isoparaffins), O (olefins), N (naphthenes), A (aromatics) 'The indicator is used to quickly assess the composition of the fraction. Due to rounding to one and the presence of unrecognized components, it may not add up to 100.0%.

Table 7. Composition of the stabilized liquid hydrocarbon product.

The output of the stabilized liquid hydrocarbon product (stable gasoline after separation of the gaseous product) to the supplied hydrocarbon fraction.

Observations

Oil refining and petrochemical industries can serve as a source of low-demand olefin-containing fractions. Such sources of olefins are usually low cost and poorly processed into commercial gasolines.

Light olefin-containing with olefin content from 10 to 50 May. % often contain hydrogen, which prevents the processing of olefin-containing fractions into high-octane gasoline components. An example of such an olefin-containing Ci ₊ fraction (first olefin-containing fraction) is SGCC, a dry catalytic cracking gas. The content of olefins in such fractions is too low for petrochemical processing. As a result, the fractions are sent for incineration (used as fuel gases).

Problems are also caused by fractions available in production with a higher content of C3-C4 olefins (50-70 wt%) and a low content of light C1-C2 gases (methane, ethane, ethylene). An example of such an olefin-containing C3-C4 fraction (second olefin-containing fraction) are propane-propylene and butane-butylene fractions. Although PPP / BBF refining processes are known, the market for such petrochemicals is limited and region-sensitive. Unlike commercial motor gasolines, classic PPF / BBF processing products may not find sufficient demand in the region where they need to be recycled.

The problem is also that the processing of olefin-containing C3-C4 fractions on zeolite catalysts by known methods leads to the production of gasolines with a high olefin content (more than 20 wt%) and a high proportion of diesel fraction (more than 5 wt%). Such a product is difficult to use for compounding commercial gasolines, where the olefin content and boiling ranges are strictly regulated.

The present method solves these problems by involving both olefin-containing fractions Cs- and olefin-containing fractions C3-C4 in the gasoline production process.

It was noted that the implementation of the proposed method allows you to reduce the content of olefins in the product to a level of 1.1 -3.0 May. %, which is significantly lower than the requirements for the content of olefins in motor gasolines.

It was also found that in the absence of the supply of the olefin-containing fraction Ci ₊ to at least one reaction zone, the proportion of the diesel fraction in the product increases by 2-6 May. %. This effect is illustrated in comparative example 5, where the olefin-containing fraction Ci _{+ was} not fed to any of the reaction zones. As a result, the share of the diesel fraction in the liquid hydrocarbon product С5 ₊ increased by May 3. %. Product containing May 2. % and more of the diesel fraction is unprofitable to use as a basis in the production of commercial motor gasolines, because in the latter, the maximum density and fractional composition are strictly controlled. The use of the proposed method makes it possible to reduce the content of the diesel fraction in the liquid hydrocarbon product C - up to May 2. % and less, which is shown in examples 1-4.

It was found that in the absence of the supply of the olefin-containing fraction Cs ₊ to at least one reaction zone, the RON of the product decreases by 4-10 units. This effect is illustrated in comparative example 6, where the olefin-containing fraction C3-C4 was not fed to any of the reaction zones. As a result, the research octane number of the product decreased by 8 units. The use of the proposed method makes it possible to obtain a product of OCHI at least 95 units, which is illustrated in examples 1-4.

Thus, the proposed method makes it possible to reduce the proportion of the diesel fraction in the liquid hydrocarbon product to May 2. % or less, and allows you to increase the RON of the product to a level above 95 units. At the same time, the yield of liquid hydrocarbon product С ₅₊ remains above 70 May. %.

Similar results are achieved simultaneously with the involvement in the gasoline production process of olefin-containing Ci ₊ fractions, such as SGCC, and olefin-containing C ₃ -C ₄ fractions, such as PPF / BBF.

These parameters make the liquid hydrocarbon product produced according to the present invention a suitable basis for the production of premium commercial motor gasolines with an octane rating of more than 95 units.

Possibility of using olefin-containing fraction Ci ₊ without preliminary separation of hydrogen from it

It was found that the proposed method allows the use of an olefin-containing fraction Ci + with an increased hydrogen content as a raw material. Moreover, the proposed method does not require additional separation of hydrogen from the olefin-containing fraction Ci ₊ .

In particular, examples 1-4 use an olefin-containing Cu fraction with a hydrogen content of 0.5 to 8 May. %. In this case, olefin-containing fractions were fed to the reaction zones without preliminary separation of hydrogen from them.

This result is important because fuel gases often contain olefins along with significant amounts of hydrogen. However, the presence of hydrogen in the olefin source can lead to side reactions. In particular, in the course of preliminary studies outside the recommended range of conditions, it was noticed that the inclusion of 0.5 - 8 May. % hydrogen in olefin-containing fractions reduces the yield liquid hydrocarbon product on May 3-6. % (while maintaining the same molar flow of olefins and a fixed mass feed rate). Additionally, when the hydrogen content in olefin-containing fractions is from 2.3 to 8 May. % there was a decrease in the share of high-octane alkyl-benzenes in the product by 0.6-2.3 May. %. Similar results could be observed due to a side process of hydrogenation of feed olefins. The application of the proposed method made it possible to suppress these negative effects, including due to the supply of oxygenate to three reaction zones. Examples 1-4 according to the invention did not show a decrease in the yield of a liquid hydrocarbon product or a decrease in the selectivity to the formation of alkyl-benzenes in the product as a result of the inclusion of hydrogen in the olefin-containing fractions of the feed.

These results make it possible to process cheap olefin-containing fractions that were previously incapable of processing into high-octane gasolines.

Ability to exclude the recycling of gaseous products

Found that the proposed method eliminates the recycle of gaseous products. All examples, according to the proposed method, show the conversion of olefins C2-C4 feed above 98 May. %. Such a high degree of conversion in one pass of the feedstock through the reactor makes it possible to abandon the use of the recycle of gaseous products for the purpose of a more complete processing of the olefins of the feedstock.

Lack of oxygenates in liquid hydrocarbon product

The proposed method makes it possible to obtain a liquid hydrocarbon product that does not contain oxygenates. Oxygenants, in particular ethanol, are often used as octane-enhancing additives in the compounding of motor gasolines. However, the maximum content of oxygenates in commercial gasolines is strictly standardized. Liquid hydrocarbon products obtained in examples 1-4 do not contain oxygenates, however, they have a high octane number according to the research method (RON of the product is above 90 units). This combination of properties allows the use of the maximum allowable amount of oxygenates when compounding commercial gasolines based on the product obtained by the proposed method.

Decrease in oxygenate consumption

Co-processing of hydrocarbon fractions and oxygenates (without the involvement of olefin-containing fractions) often makes it possible to obtain gasolines with high RON and high product yields. However, oxygenates such as methanol, ethanol, dimethyl ether are rarely available in refineries as cheap feedstocks. When the source of oxygenate cannot be found in the by-product or intermediate product of the enterprise itself, it has to be purchased from outside at prices marketable product. This increases the cost of producing a unit of commercial gasoline, and complicates the logistics of production.

It was found that it is possible to reduce the consumption of oxygenates for the production of gasoline by partially replacing oxygenates with low-demand olefin-containing fractions. This approach allows you to reduce the consumption of oxygenates while maintaining the yield and quality of the product.

In particular, the proposed method makes it possible to partially replace oxygenates with a source of dilute olefins (the first and second olefin-containing fractions). In examples 1-4, olefin-containing fractions act as a partial replacement for oxygenates of the feed.

The calculation of the percentage of substitution of oxygenates for olefin-containing fractions is carried out according to formulas (4) - (6) on pages 3-4 of this Description. In this case, molar streams of olefins supplied to the reaction zones as part of the first and second olefin-containing fractions are added. Examples according to the invention show the possibility of replacing from 82 to 95% of oxygenate by olefin-containing fractions to obtain an RON of liquid hydrocarbon product above 95 units. and product release over May 70. % on the supplied hydrocarbon fraction.

The provided formulas (4) - (6) can be applied to the already known methods of joint processing of hydrocarbon fractions and oxygenates (previously without the involvement of olefin-containing fractions) into gasolines. In this case, formulas (4) - (6) make it possible to calculate the amount (molar flow, mol / h) of oxygenate in a known method, which can be replaced by available olefin-containing fractions without loss of quality and product yield.

Distributed supply of hydrocarbon fraction

It was noticed that changing the supply of the hydrocarbon fraction to the reaction zones makes it possible to control several parameters of the process. In particular, the distribution of the hydrocarbon fraction into two or three reaction zones makes it possible to further increase the yield and / or selectivity of the formation of C ₅ - hydrocarbons (hydrocarbons with five or more carbon atoms). Also, in the case of distributed feeding of the hydrocarbon fraction to several reaction zones, cracking of isoparaffins with two or more alkyl substituents with the formation of lower hydrocarbons C1-C4 can be suppressed. Also, as a result of the distribution of the hydrocarbon fraction into several reaction zones, a decrease in the dealkylation of alkylaromatic hydrocarbons can be observed. In particular, Example 7 shows the possibility of distributing the hydrocarbon fraction over several reaction zones. Example 7 repeats the conditions of Example 1, except for a change in the distribution of the hydrocarbon fraction. In example 1, the distribution of the hydrocarbon fraction over the reaction zones Rioi / R201 / R301 was 100/0/0 May. %. Example 7 retains the same mass flow rates of raw materials as Example 1, however, the hydrocarbon fraction is distributed over the three reaction zones in a ratio of 50/30/20 May. %. As a result, it is possible to increase the product yield on May 4th. % for the supplied hydrocarbon fraction (from 74.8 to 78.9 wt.% for a liquid hydrocarbon product that does not contain dissolved gases).

The aromatics content in the product of Example 7 (liquid hydrocarbon product not containing dissolved gases C1-C4) is reduced by 2.6 May. % compared to example 1 (from 51.1 to 48.5 May.%). Typically, as the concentration of aromatics in the product decreases, the octane rating of the product is expected to decrease. However, it was found that the RTI of the product of Example 7 is practically indistinguishable from the RTI of the product of Example 1 (96.6 units and 96.4 units, respectively). This effect can be explained by a decrease in the cracking of high-octane isoparaffins C _? -Cx (isoparaffins with individual research octane numbers more than 72 units) as a result of the distributed supply of the hydrocarbon fraction to several reaction zones.

Also, if necessary, it is possible to distribute the entire flow of the hydrocarbon fraction only to the second or only to the third reaction zone.

Claims

FORMULA

1. A method for producing gasolines, in which four streams are used as raw materials, the first of which includes a hydrocarbon fraction, the second stream includes an oxygenate, the third stream includes a first olefin-containing fraction, the fourth stream includes a second olefin-containing fraction, and: a. the first olefin-containing fraction includes one or more olefins selected from the group consisting of ethylene, propylene, butylenes, isobutylene, in a total amount of 10 to 50 May. % and includes 0.5-8.0 May. % hydrogen,

2. The method of claim 1, wherein the distribution of the second stream between the three reaction zones is 40-85 May. % / 10-35 May. % / 5-25 May. % of the total amount of the second stream.

3. A process according to claim 1, wherein the first stream is preferably fed to the first reaction zone.

4. The method according to claim 1, wherein the hydrocarbon fraction contains normal paraffins in an amount of 15-24 May. %, isoparaffins in the amount of 42-56 May. %, naphthenes in the amount of May 22-40. %, the rest is aromatic hydrocarbons and olefins.

5. The method of claim 1, wherein the hydrocarbon fraction contains from 0 to 80 May. % of hydrocarbons Sat, preferably from 23 to 46 May. % of hydrocarbons Sat, most preferably from 36 to 46 May. % hydrocarbons C _b .

6. The method according to claim 1, wherein the hydrocarbon fraction contains from 0 to 70 May. % Ci isoparaffins, preferably from 26 to 50 May. % isoparaffins i, most preferably from 26 to 38 May. % of isoparaffins Ci.

7. The method according to claim 1, in which the hydrocarbon fraction can be selected from the group including straight-run gasoline, stable gas gasoline, light gas condensate, gasoline fraction with boiling points of about 62 ° - 85 ° C, raffinate, and mixtures thereof.

8. A process according to claim 1, wherein the first olefin-containing fraction is selected from the group consisting of dry catalytic cracking gas, catalytic cracking gas, coker off-gas, catalytic reformer off-gas, Fischer-Tropsch off-gas, pyrolysis gas , fuel gases of various origins, as well as mixtures thereof.

9. The method of claim 1, wherein the first olefin-containing fraction comprises

May 2.3-8.0. % hydrogen, preferably 3.2-8.0 wt. % hydrogen.

10. The method according to claim 1, wherein the mass fraction of C5 ₊ hydrocarbons in the first olefin-containing fraction is from 0 to 10.0 wt%. %, preferably from 0 to 5.0 May. %.

11. The method according to claim 1, in which the first olefin-containing fraction contains hydrocarbon components selected from the group: methane, ethane, propane, butane, and / or inorganic gases selected from the group: hydrogen, nitrogen, and / or impurities more heavy olefins C5 ₊ selected from the group: pentenes, hexenes.

12. The method of claim 1, wherein the second olefin-containing fraction is selected from the group consisting of propane-propylene fractions, butane-butylene fractions, catalytic cracking wet gas, and mixtures thereof.

13. The method according to claim 1, in which the oxygenate is selected from the group consisting of aliphatic alcohols and ethers, for example, methanol, ethanol, crude methanol, technical methanol, dimethyl ether, as well as mixtures thereof, including with water.

14. A process according to claim 1, wherein the oxygenate may contain impurities, for example, aldehydes, carboxylic acids, esters, unsaturated alcohols.

15. The method of claim 1, wherein the zeolite catalyst comprises: a. zeolite of the ZSM-5 type with the S1O2 / AI2O3 module from 43 to 95, in an amount from 65 to 80 May. %,

B. sodium oxide in an amount from 0.04 to 0.15 May. %, c. zinc oxide in the amount of 1.0-5.5 May. %, d. oxides of rare earth elements in a total amount of 0.5-5.0 May. %, e. a binder comprising silicon dioxide, aluminum oxide, or mixtures thereof.

16. The method of claim 15, wherein the zeolite catalyst is free of platinum metals.

17. The method of claim 15, wherein the rare earths are selected from the group consisting of lanthanum, praseodymium, neodymium, cerium, and mixtures thereof.

18. The method according to claim 1, in which the mass feed rate of the raw material is

0.5-10 h ¹ , preferably 1-3 h ¹ .

19. A method according to claim 1, wherein the process pressure is 1.5 to 4.0 MPa, preferably 2.2 to 2.7 MPa.

20. The method of claim 1, wherein the hydrocarbon fraction is 70-83 May. % of the supplied raw materials.

21. The method of claim 1, wherein the first olefin-containing fraction is

May 4-19. % of the supplied raw materials.

22. The method of claim 1, wherein the second olefin-containing fraction is

May 3-14. % of the supplied raw materials.

23. The method according to claim 1, wherein the temperature of the stream at the inlet to the first / second / third reaction zone is 350-380 ° C / 340-370 ° C / 340-370 ° C.

24. The method according to claim 1, in which the distribution of the catalyst over the reaction is 17-33 May. % / May 28-50. % / 33-50 May. % of the total amount of catalyst for the first / second / third reaction zone, respectively.

25. The method of claim 1, wherein the reaction is carried out in the gas phase in a fixed bed of catalyst.