RU191347U1 - DEVICE FOR SEPARATION OF BENZENE ALKYLATION REACTION PRODUCTS - Google Patents

Abstract

The utility model relates to the chemical and petrochemical industries, in particular to devices for separating the liquid and gas phases of the reaction product, and can be used in various industries for the most complete phase separation. The separator contains an outer casing (1), which is a cylindrical shell with upper (2) and lower (3) covers. In the bottom cover (3) there is a pipe (7) for withdrawing the liquid phase of the reaction products. The inlet of the reaction products (4), the thermocouple pocket (6) and the outlet pipe for the gaseous phase of the reaction products (5) are placed in the top cover. In the cylindrical part of the shell, there are nozzles for the inlet (8) and outlet (9) of the coolant, which are connected to the circulation cooler. A product receiver (10) is placed inside the housing (1), which is a cylindrical shell with upper (I) and lower (12) covers. In the bottom cover (12) there is a pipe (7) for withdrawing the liquid phase of the reaction products. The inlet of the reaction products (4), the thermocouple pocket (6) and the outlet pipe for the gaseous phase of the reaction products (5) are placed in the top cover. The pipe (4) is located in the product receiver (10) at a height of 2/3 of the total height of the receiver (10). The thermocouple pocket is located at a height of 5 mm from the bottom cover (12) of the receiver (10). The outlet pipe of the gas phase (5) and the outlet pipe of the liquid phase (7) are welded flush with the caps (11) and (12), respectively. The inlet (8) and outlet (9) of the coolant are welded flush with the shell (1).

Description

Technical field

The utility model relates to the chemical and petrochemical industries, as well as to laboratory equipment, namely, devices for separating the liquid and gas phases of the initial product, and can be used in various industries for the most complete separation of phases, including during the alkylation reaction benzene, as well as during laboratory studies of the alkylation reaction of benzene with propylene (ethylene).

State of the art

A sufficiently complete separation of liquid and gaseous reaction products in industry and laboratories causes quite big problems. For the most part, before gaseous and liquid reagents (products) get into the separator for separation, they are pre-cooled in heat exchangers or refrigerators. At the same time, the designs of industrial separators are characterized by a more complex structure, which makes them inapplicable for use in laboratory conditions when conducting various studies.

A known method of separating associated gas into liquid and gas fractions and installation for implementing the method (application for invention EA 200870047 A1), in which natural gas is cooled before separation from the liquid and only then it enters the separator, where it is separated from the water. The disadvantage of this solution is the presence of preliminary cooling of the gas-liquid mixture, which increases the separation process by one stage. The installation is characterized by the presence of separate cooling and associated gas separation units, which is inconvenient if the separation process is implemented in laboratory conditions.

Also known is the method and installation of hydrotreatment of diesel fuel (Patent RU 2323958), where the reaction mixture before entering the separation in the separator, as in the previous method, first goes through the cooling stage, and only then goes to the separation. The installation includes two heat exchangers, between which a tube furnace and a reactor are placed along the technological cycle; a high-pressure separator located at the outlet of the second heat exchanger (providing preliminary cooling of the reaction products) is connected with its output to the unit for purification of hydrogen-sulfide from hydrogen sulfide, and the second through a heater with a stabilization column.

This solution is characterized by the disadvantage presented in the description of the previous analogue, including associated with the need for preliminary cooling of the reaction mixture.

Closest to the claimed design is a device for vacuum separation of titanium of the Russian Federation 2240370, by the number of common features adopted for the closest prototype. The device comprises a container for installing a separation apparatus in it, made in the form of a cylinder with a cone in the lower part, with nozzles for supplying and discharging liquid, nozzles for supplying and discharging air, while it is equipped with a caisson mounted on the outer surface of the cylindrical part of the tank, this nozzles for supplying fluid are placed on the box in its lower part, and the nozzles for draining the liquid in its upper part. The invention allows to increase the service life of the cooling device and the vacuum separation apparatus due to the parallel supply of liquid and air in a closed jacket without the formation of steam.

The disadvantage of this device is the design complexity of the cooling apparatus and the complete cooling of the apparatus, which does not provide a sufficiently complete separation of the liquid and gas phases of the reaction product.

Utility Model Disclosure

The technical problem solved by the present utility model is the development of a separator, preferably for separating the products of the benzene alkylation reaction under laboratory conditions, which prevents the transition of benzene to the gas phase and a clearer separation of the reaction products and unreacted gas.

The technical result provided by the claimed technical solution is a more complete separation of the gaseous and liquid products of the alkylation reaction by increasing the cooling surface, as well as cooling the nozzle of the inlet stream, which prevents the transition of benzene into the gas phase and thereby more clearly separate the unreacted gas from the reaction products . The inventive device is also characterized by simplicity of design and ease of maintenance including during laboratory research.

The problem is solved in that the device for separating the products of the reaction of alkylation of benzene into liquid and gas phases includes a vertically oriented housing for a shared reaction product (inner case or receiver of reaction products), equipped with three nozzles - input of the reaction product, output of the liquid phase, output of the gaseous phase ; thermocouple located in the housing; and an external cooling circuit of the housing, made with the possibility of connecting through the nozzles of the inlet and outlet of the coolant to the circulation cooler, while the external cooling circuit is implemented as an external housing, made in the form of a cylindrical shell with upper and lower covers, and having dimensions that accommodate housing for a shared reaction product with the possibility of cooling this housing over its entire surface, while the nozzles of the input of the reaction product and the output of the gaseous phase passing through the top cover of the outer case, the liquid phase outlet pipe through its bottom cover, the coolant inlet pipe is located in the lower part of the outer case, and the coolant outlet pipe in its upper part, the thermocouple is placed in the housing for the reaction product to be separated with the possibility temperature measurements over the entire height of the given case, and the inlet of the reaction product inlet is placed in this case at a depth of at least 2/3 of its height.

The inner case for the reaction product to be divided is made in the form of a cylindrical shell with upper and lower covers or in the form of a cylinder with a bottom and top cover, and is coaxial with the outer case. The thermocouple is located at a height of 2-5 mm (not less than 1/30 of the height of the inner cylindrical shell) from the bottom cover of the housing for a shared reaction product. The distance between the upper covers of the outer shell and the shell for the shared reaction product is 3-10 mm (at least 1/17 of the height of the outer cylindrical shell). The distance between the lower covers of the outer shell and the shell for the shared reaction product is 3-10 mm (at least 1/17 of the height of the outer cylindrical shell). The distance between the cylindrical shells of the outer shell and the shell for the shared reaction product is 10-20 mm (at least 1/7 of the height of the outer cylindrical shell).

In specific embodiments of the device, the inlet of the reaction product may be threaded for connection to a benzene alkylation reactor; the outlet port of the gaseous phase (unreacted gas) is threaded for connection to a gasometer. The outlet port for the gaseous phase and the outlet port for the liquid phase are welded flush with the upper and lower covers, respectively. Coolant inlet and outlet nozzles are welded flush with the shell. The bottom cover or bottom of the inner case is made in the form of a cone for a more complete discharge of the liquid phase from the separator.

Brief Description of the Drawings

The invention is illustrated by drawings, where in FIG. 1 is a sectional perspective view of the separator; FIG. 2 is a schematic diagram of a laboratory setup using a separator of the claimed design.

The positions in the figures denote: 1 - outer casing; 2 - top cover; 3-lower cover; 4 - pipe inlet products; 5 - pipe outlet of the gaseous phase; 6 - pocket thermocouple; 7 - pipe outlet liquid phase of the products; 8 - pipe inlet of the coolant; 9 - pipe outlet coolant; 10 - product receiver (inner case); 11 - the top cover of the receiver; 12 - bottom cover of the receiver; 13 - reactor; 14 - catalyst layer; 15 - furnace for heating the reactor, 16 - separator, 17 - gas meter, 18 - measuring cylinder;

Utility Model Implementation

Below is a more detailed description of the design of the claimed device.

The separator (Fig. 1) consists of two main units: the outer case (1) with the top (2) and bottom (3) covers and the product receiver (inner case) (10) with the top (11) and bottom (12) covers. The outer casing (1) is a cylindrical shell limited by a top cover (2) on top and a bottom cover (3) on the bottom. The inlet pipes (8) and the outlet (9) of the coolant are mounted in the outer casing (1). As a coolant, antifreeze is usually used, which is circulated using a circulation cooler. A product inlet pipe (4), a thermocouple pocket (6), a product gas outlet pipe (5) and a liquid product phase outlet pipe (7) pass through the top cover (2) of the outer case (1). The product receiver (10) is a cylindrical shell, bounded above by a top cover (11), below - a bottom cover (12), made in the shape of a cone. A product inlet pipe (4) is mounted in the product receiver, lowered down 2/3 of the height of the receiver, the inner diameter of the pipe must be at least 1/2 of the inner diameter of the reactor (the pipe is aligned with the reactor), and the thermocouple pocket (6) located at a distance 5 mm (not less than 1/30 of the height of the inner cylindrical shell) from the bottom cover (12), the outlet pipe for the gaseous phase of the products (5) mounted on the top cover (11) and the outlet pipe on the liquid phase of the products (7) mounted on the bottom cover (12).

The separator works as follows.

The separator is connected to the reactor by means of a thread on the product inlet pipe (4). The coolant (antifreeze) by means of a circulation cooler enters the coolant inlet pipe (8), fills all the free space of the outer casing (1) and leaves the coolant outlet pipe (9). In the outer casing, the reaction products are pre-cooled by cooling the nozzles (4) and (5), which makes it possible to more completely cool the liquid phase of the products and prevent benzene from entering the gas phase. Through the product inlet pipe (4), the liquid and gas phases of the reaction products enter the product receiver (10), where the liquid phase of the products is cooled even more and accumulates in the lower part of the receiver (10) on the lower cover (12), made in the form of a cone for more complete withdrawal of products, as they accumulate, through the pipe (7). Cooling of the liquid phase is necessary so that the liquid phase of the product does not pass into the gaseous phase and is not removed together with unreacted gas through the pipe (5).

To test the operation of the claimed device, a separator sample was made, which was tested in a laboratory flow-through installation for the alkylation (transalkylation) of benzene with a steel integral reactor using heterogeneous catalysts, namely, zeolite alkylation catalysts. All structural elements of the device are made of stainless steel grade 12X18H10T dimensions of the external cylinder (cylindrical shell): diameter - 70 mm; height - 85 mm. Dimensions of the inner cylinder (cylindrical shell): diameter - 40 mm; height - 75 mm. The size of the pipe (4) is 82 mm, the size of the pipe (5) is 55 mm, the size of the pipe (6) is 83.5 mm, the size of the pipe (7) is 30 mm, the size of the pipes (8, 9) is 26.5 mm . The distance between the covers (2), (11) and (3), (12) is 3.5 mm. This device was used to separate the liquid phase of products from the gas phase (unreacted gas) of the benzene alkylation process with propylene. To cool the entire contour of the inner cylinder and nozzles, a liquid circulation cooler from LAUDA Microcool MC 250 was used, antifreeze was used as a coolant (to -40 ° C).

The experiments on the alkylation of benzene with propylene were carried out in a flow unit (Fig. 2) with a steel integrated reactor (13) with a volume of 10 cm ³ with a loading of the catalyst, which was used various zeolites with a volume of 2 cm ³ . The reactor is heated by means of a stove (14). Before each experiment, dehydration was carried out in a stream of inert gas (V), which was supplied by a gas flow regulator (RRG-2) with a stepwise increase in temperature and holding for a certain time. Upon completion of dehydration, the system was cooled to the temperature of the experiment. The experiment began with the supply of benzene (II) pump (H-1). Benzene was supplied until the first drop appeared from the separator of the claimed design (15), which is an indicator that the system is filled with benzene, after which the flow of propylene (I) began. Propylene was fed into the reactor (13) with a gas flow regulator (RRG-1). After the reaction, unreacted propylene was separated from the reaction products in a separator (16), accumulated in a gasometer (17), displacing liquid from it, which was collected in a measuring cylinder (18). The amount of displaced liquid was determined by the amount of propylene, which did not react.

Experiments on the alkylation of benzene were carried out under certain standard conditions: temperature 205 ° C, atmospheric pressure, the molar ratio of benzene / propylene 10/1, the feed rate of benzene 10 h ^-1 . The total duration of the experiment is 240 minutes; sampling was carried out every 40 minutes.

The alkylation products were analyzed on a Shimadzu GC2030 gas chromatograph with a flame ionization detector and a capillary column (DB-1, 100 m * 0.25 mm * 0.50 μm).

The inventive device during the separation of the products of the reaction of alkylation of benzene in laboratory conditions showed a clearer separation of the reaction products and unreacted gas. This result is explained by an increase in the cooling area (cooling of the entire inner cylinder, as well as the incoming pipes), due to which a more complete cooling of the liquid phase is achieved; due to more complete cooling of the liquid phase in which benzene is contained, it does not go into a gaseous state and benzene vapors are not observed in the outgoing unreacted gas during analysis. The presence of a thermocouple pocket inside the device and the circulation thermostat allows you to accurately maintain the desired cooling temperature.

The claimed technical solution is implemented using industrially produced devices and materials, can be manufactured at any laboratory or industrial enterprise and will be widely used in various fields of organic and petrochemical synthesis.

Claims (9)

1. A device for separating the products of the reaction of alkylation of benzene into liquid and gas phases, including a vertically oriented housing for a shared reaction product, equipped with three nozzles - input of the reaction product, output of the liquid phase, output of the gaseous phase; thermocouple located in the housing; and an external cooling circuit of the housing, configured to connect through the nozzles of the inlet and outlet of the coolant to the circulation cooler, characterized in that the external cooling circuit is implemented as an external housing, made in the form of a cylindrical shell with upper and lower covers, and having dimensions that provide placing in it a housing for a shared reaction product with the possibility of cooling this housing over its entire surface, while the nozzles of the input of the reaction product and the output of gaseous the phases are made passing through the upper cover of the outer casing, the liquid phase outlet pipe is through its lower cover, the coolant inlet pipe is located in the lower part of the external housing, and the coolant outlet pipe is in its upper part, the thermocouple is placed in the housing for the reaction product to be separated with the ability to measure temperature over the entire height of a given building, and the inlet of the reaction product inlet is placed in this case at a depth of at least 2/3 of its height. 2. The device according to p. 1, characterized in that the housing for a shared reaction product is made in the form of a cylindrical shell with upper and lower covers and is located coaxially with the external housing. 3. The device according to p. 1, characterized in that the thermocouple is located at a height of 2-5 mm from the bottom cover of the housing for a shared reaction product. 4. The device according to p. 2, characterized in that the distance between the upper covers of the outer shell and the shell for the shared reaction product is at least 1/17 of the height of the outer cylindrical shell. 5. The device according to p. 2, characterized in that the distance between the lower covers of the outer shell and the shell for the shared reaction product is at least 1/17 of the height of the outer cylindrical shell. 6. The device according to claim 1, characterized in that the distance between the cylindrical shells of the outer shell and the shell for the shared reaction product is at least 1/7 of the height of the outer cylindrical shell. 7. The device according to claim 1, characterized in that the inlet pipe of the reaction product is threaded for connection to a benzene alkylation reactor. 8. The device according to p. 1, characterized in that the outlet pipe of the gaseous phase is threaded for connection to a gasometer. 9. The device according to p. 2, characterized in that the lower housing cover for a shared reaction product is made in the form of a cone for draining the liquid phase from the separator.

Images