CN-117654077-B - Catalytic reaction rectification unit, equipment and method

CN117654077BCN 117654077 BCN117654077 BCN 117654077BCN-117654077-B

Abstract

The invention discloses a catalytic reaction rectifying unit, equipment and a method, wherein the catalytic reaction rectifying unit comprises a reaction mass transfer channel, a catalyst layer and a packing layer are arranged in the reaction mass transfer channel, the catalyst layer is arranged above the packing layer, a first space is arranged between the catalyst layer and the packing layer, a gas lifting bypass is arranged outside the reaction mass transfer channel and communicated with the first space, a liquid phase product after catalytic reaction is converged with the high-temperature gas phase in the packing layer and carries out gas-liquid mass transfer, and the light component in the liquid phase product is carried by the gas lifting phase after mass transfer to enter the gas lifting bypass to finish mass transfer separation. By arranging the gas lifting bypass, the invention not only can improve the circulation speed of gas phase and effectively reduce the pressure drop in the reaction mass transfer channel, but also can effectively solve the space occupation problem of equipment. The invention can clear the blockage of the catalyst filter screen without extra power, and can realize the online replacement of the catalyst and/or the filler.

Inventors

GAO FENG
GAO XIANHUI
YUAN YING
YU YING
JIANG YANG

Assignees

中国石油化工股份有限公司
中石化（大连）石油化工研究院有限公司

Dates

Publication Date: 20260505
Application Date: 20220830

Claims (11)

1. A catalytic rectification unit, comprising: the reaction mass transfer channel is internally provided with a catalyst layer and a packing layer, and the catalyst layer is arranged above the packing layer with a first space between the catalyst layer and the packing layer; The gas-liquid separation device comprises a reaction mass transfer channel, a gas-lifting bypass, a sealing plate and a sealing plate, wherein the gas-lifting bypass is positioned at the outer side of the reaction mass transfer channel and is communicated with the first space, a liquid phase product after catalytic reaction is converged with the high-temperature gas phase at the filler layer and carries light components in the liquid phase product after mass transfer into the gas-lifting bypass for mass transfer separation, a blocking removing mechanism is arranged at the corresponding position of the catalyst layer in the gas-lifting bypass and is used for removing blocking of a filter screen of the catalyst layer by utilizing gas phase pressure in the first space when the descending liquid phase is blocked by the catalyst layer, the blocking removing mechanism comprises an overflow pipe, the upper end of the overflow pipe is communicated with an overflow inlet positioned above the catalyst layer in the reaction mass transfer channel, the lower end of the overflow pipe is provided with a reducing port, a corrugated section is arranged on the overflow pipe and is used for enabling the overflow pipe to extend downwards after the overflow liquid phase enters the overflow pipe and is full, the sealing plate is arranged at the lower part of the reducing port, the overflow outlet is arranged on the sealing plate and is opposite to the reducing port, and the rising gas phase is blocked in the first space when the overflow plate extends downwards to the sealing plate.
2. The catalytic distillation unit as set forth in claim 1, wherein the reaction mass transfer channel is provided with a first removal flange at both ends for replacement after the reaction mass transfer channel is integrally removed after the catalyst and/or packing has failed.
3. The catalytic rectification unit of claim 2, wherein a second space is provided in said reaction mass transfer channel below said packing layer to said first flange location, and wherein a side wall of said second space is provided with an updraft branch for providing said high temperature gas phase.
4. The catalytic distillation unit as set forth in claim 3, wherein said lift leg includes a vertical section and a bent section extending obliquely downward from a top of the vertical section to a side wall of said reaction mass transfer channel and communicating with said second space.
5. The catalytic rectification unit of claim 4, wherein said vertical section of said riser and said riser bypass are each provided with a second dismounting flange at a location corresponding to said first dismounting flange.
6. Catalytic rectification apparatus, comprising a catalytic rectification unit as claimed in any one of claims 1 to 5, wherein a plurality of catalytic rectification units are arranged transversely on each tray.
7. The catalytic distillation apparatus as set forth in claim 6, wherein the upper ends of the reaction mass transfer channels in each of said catalytic distillation units are in communication with a liquid phase manifold which receives liquid phase product from an upper tray.
8. The catalytic rectification apparatus of claim 6, wherein each of said catalytic rectification units has a lift bypass in communication with a gas phase manifold and lift branches in communication with a gas phase manifold of the lower tray.
9. A catalytic rectification method, characterized in that a catalytic rectification unit according to any one of claims 1 to 5 is applied, which catalytic rectification unit is provided in a plurality of and transversely arranged stages on each stage, comprising the steps of: A. two or more low-temperature liquid-phase reactants enter a catalyst layer in a reaction mass transfer channel from top to bottom to perform catalytic reaction; B. The liquid phase product after catalytic reaction is mixed with high temperature gas phase from bottom to top in the stuffing layer of the reaction mass transfer channel and gas-liquid mass transfer is carried out, and the ascending gas phase after mass transfer carries light components in the liquid phase product to enter the ascending gas bypass, so as to complete mass transfer separation.
10. The catalytic rectification method according to claim 9, wherein, when the catalytic reaction is carried out for a while and when clogging of the filter screen of the catalyst layer occurs, the liquid phase enters an overflow pipe provided in the ascending gas bypass through an overflow inlet, and extends downward through the overflow pipe to the sealing plate so that the liquid phase flows out through the overflow outlet and into a first space in the reaction mass transfer passage while the ascending gas phase is blocked in the first space, and the gas pressure in the first space rises until the clogged filter screen is dredged.
11. The catalytic rectification method of claim 9, wherein when catalytic rectification apparatus is in operation for a period of time requiring replacement of catalyst and/or packing, one of said catalytic rectification units is removed integrally from the first and second removal flanges while the other catalytic rectification units are still in operation, completing on-line replacement of said catalyst and/or packing.

Description

Catalytic reaction rectification unit, equipment and method Technical Field The invention relates to the technical field of petrochemical industry, in particular to a catalytic reaction rectification unit, equipment and a method. Background The catalytic reaction rectification equipment is gas-liquid mass transfer equipment which takes the reaction and rectification process into consideration, and the catalytic rectification technology has wide application in the etherification reaction, the esterification reaction and the alkylation reaction. Compared with the traditional process flow in which the reactor and the rectifying tower are independently used, the use of the catalytic reaction rectifying equipment can greatly reduce the operation and investment cost. In the existing catalytic reaction rectifying equipment, a mode of arranging catalytic reaction sections and mass transfer separation sections at intervals is generally adopted, and the occupied space of the equipment is large by adopting the mode of arranging the catalytic reaction sections and the mass transfer separation sections at intervals vertically. For example, chinese patent application CN102824752a discloses a catalytic distillation column, which comprises a column body, a catalytic reaction section and a separation section, wherein the catalytic reaction section and the separation section are combined alternately and are disposed in the column body. The catalyst can be completely immersed in the reaction liquid, so that gas phase scouring is avoided, the change of the dry and wet of the surface of the catalyst is avoided, and the service life of the catalyst is prolonged. In addition, anti-plugging and online replacement of heterogeneous catalysts are currently a major concern in the industry. Heterogeneous catalysts are solid particles with a certain volume, which are very easy to cause the blockage of tower internals and further influence the normal operation of equipment, so that the problems of blockage are solved and the occurrence of blockage phenomenon is reduced as much as possible. The activity and selectivity of the catalyst are reduced to a certain extent after the catalyst is used for a period of time, and the catalyst in the tower needs to be replaced periodically in order to ensure that the reaction product meets the quality requirement. The catalyst is replaced by stopping, which can cause frequent start-up and stop of the production device, has poor economical efficiency and has been phased out. Therefore, there is a need for a catalytic reaction rectification apparatus that effectively saves space while satisfying the reaction and rectification effects, and that can effectively solve the problems of catalyst blockage and online replacement. The information disclosed in this background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person of ordinary skill in the art. Disclosure of Invention The invention aims to provide a catalytic reaction rectifying unit, equipment and a method, which can not only improve the circulation speed of gas phase and effectively reduce the pressure drop in a reaction mass transfer channel, but also effectively solve the space occupation problem of the equipment by arranging a gas lifting bypass. Another object of the present invention is to provide a special structural design of the overflow pipe in the gas-lift bypass, which can not only guide the liquid phase into the gas-lift bypass and bypass the blocked portion, but also clear the blocked portion of the catalyst screen by using the gas phase pressure raised in the space below the catalyst layer. It is still another object of the present invention to provide a catalytic reaction distillation apparatus that can replace catalyst and/or packing on-line. In order to achieve the aim, according to a first aspect of the invention, a catalytic reaction rectification unit is provided, which comprises a reaction mass transfer channel, a gas lifting bypass and a gas lifting bypass, wherein the upper end of the reaction mass transfer channel receives low-temperature liquid phase reactant running from top to bottom, the lower end of the reaction mass transfer channel receives high-temperature gas phase running from bottom to top, a catalyst layer and a packing layer are arranged in the reaction mass transfer channel, the catalyst layer is arranged above the packing layer, a first space is arranged between the catalyst layer and the packing layer, the gas lifting bypass is positioned outside the reaction mass transfer channel and is communicated with the first space, liquid phase products after the catalytic reaction are converged with the high-temperature gas phase at the packing layer and carry light components in the liquid phase products after the mass transfer into the gas