Radial flow reactor for producing piperazine and co-producing triethylene diamine from ethylenediamine

Abstract

The utility model discloses a radial flow reactor for producing piperazine and co-producing triethylene diamine from ethylenediamine, which comprises a catalyst feeding channel, a catalyst discharging channel, a raw material gas feeding channel, a product gas discharging channel and a catalyst removing device, the catalyst removing device is an adjustable pore plate arranged between the inner shell and the outer shell of the reactor, the adjustable pore plate and a product air outlet in the inner shell form different pore sizes through adjustment, the catalyst in the bed height corresponding to the maximum gap can be discharged, the discharged catalyst enters a catalyst hopper below, and the catalyst is discharged from the catalyst hopper. And discharging along with the replaced catalyst. The device has the beneficial effects that the catalyst can be discharged in a layered manner according to the state of the catalyst of each bed layer, so that the operation flexibility is improved, and the problem that the catalyst can only be discharged from the bottom layer and sequentially replaced is solved.

Description

TECHNICAL FIELD

[0001] The utility model relates to radial reactor field especially relates to a radial flow reactor for ethylenediamine production piperazine co-production triethylene diamine. BACKGROUND

[0002] The reaction of ethylenediamine production piperazine co-production triethylene diamine is strong exothermic reaction, and piperazine is an important pharmaceutical intermediate and has great application value, but when producing piperazine from ethylenediamine, producing triethylene diamine has more advantages from the reaction thermodynamics.Compared with piperazine, the application field of triethylene diamine is smaller, and how to improve the selectivity of piperazine is a key problem.In order to improve the selectivity of piperazine, large space velocity operation can be used, or the outer surface acid site of the catalyst can be modified, or the conversion rate can be reduced.

[0003] At present, the reactor used in the industry of ethylenediamine production piperazine co-production triethylene diamine is a fixed bed reactor, although various schemes can be taken to take heat, but the axial or radial temperature difference of the reaction is relatively large, which is not conducive to improving the selectivity of the reaction.If a fixed bed reactor of tube type is used, and combined with the forced flow of heat transfer fluid in the tube to take heat, although the axial and radial temperature uniformity of the reactor can be improved, but the equipment processing and manufacturing, and the catalyst filling requirement are high, and when the catalyst performance decays, the catalyst must be replaced after shutdown, which is more troublesome. SUMMARY

[0004] According to the problems existing in the prior art, one of the purposes of the utility model is to disclose a radial flow reactor for ethylenediamine production piperazine co-production triethylene diamine, which can realize the discharge of different bed layers of deactivated catalyst by adding adjustable orifice plates, maintain other active catalysts unchanged, and facilitate the replacement of catalysts.The second purpose of the utility model is to disclose a radial flow reactor for ethylenediamine production piperazine co-production triethylene diamine, which can reduce the temperature difference between the axial and radial directions and prolong the service life of the catalyst.

[0005] The technical scheme adopted by the utility model is as follows:

[0006] A radial flow reactor for ethylenediamine production piperazine co-production triethylene diamine, comprising a catalyst feed channel, a catalyst discharge channel, a raw material gas feed channel and a product gas discharge channel.

[0007] The catalyst feed channel is arranged at the upper end of the reactor and comprises a catalyst feed port, a plug valve A, a plug valve B, a feed tee valve and an intermediate bin.

[0008] The catalyst discharge channel is arranged at the lower end of the reactor and comprises a catalyst discharge port, a plug valve C, a plug valve D, a discharge tee valve and a catalyst discharge hopper.

[0009] The raw material gas feeding channel comprises a feeding port arranged on the outer wall of the reactor and a distribution pipe arranged in the center of the reactor, the distribution pipe is communicated with the feeding port on the side, the upper and lower ends of the distribution pipe are closed, and a plurality of micro holes are arranged on the wall of the distribution pipe for feeding the raw material gas.

[0010] The vertical part of the reactor is divided into an outer shell and an inner shell, and a distance is kept between the outer shell and the inner shell.

[0011] The catalyst removal device is an adjustable hole structure, preferably an adjustable hole plate, which is tightly attached to the outer side of the inner shell and can move along the outer side of the inner shell.

[0012] The product gas discharge channel comprises a product gas outlet arranged on the inner shell of the reactor and a gas collecting port arranged on the outer shell, the product gas overflows from the opening of the inner shell, flows through the channel between the inner shell and the outer shell, and is collected by the gas collecting port.

[0013] The product gas outlet is a circular opening arranged on the inner shell, and the adjustable hole plate is provided with a plurality of uniformly distributed openings, the opening distribution of the adjustable hole plate corresponds to the positions of the product gas outlets one by one, the sizes are the same, and all are greater than the diameter of the catalyst particles. The adjustable hole plate can move in the horizontal direction along the outer side of the inner shell of the reactor, and when it moves to a certain position, the adjustable hole plate and the product gas outlet can form different pore sizes.

[0014] For example, the catalyst is a small ball with a diameter of 5mm, the opening of the product gas outlet and the adjustable hole plate is greater than 3-5mm, the discharged catalyst enters the lower catalyst hopper and is discharged together with the replaced catalyst.

[0015] The adjustable hole plate is evenly divided into four sections along the longitudinal coordinate direction, and each section can be moved independently.

[0016] The adjustable hole plate is controlled to move by an eccentric wheel, so as to be adjusted, the eccentric wheel is controlled manually, and a handle is arranged on the outer shell of the reactor.

[0017] The radial flow reactor for producing piperazine and triethylene diamine byproduct in the production of ethylenediamine has the following advantages:

[0018] 1. (1) The reaction occurs simultaneously in the axial and radial directions, resulting in a uniform temperature field. (2) The catalyst in each bed can be unloaded in layers according to its state, improving operational flexibility and solving the problem that it can only be unloaded from the bottom layer and replaced sequentially. (3) Catalysts with declining performance can be replaced online continuously, improving operational stability. (4) Product gas can be quickly removed from the catalyst, reducing the occurrence of side reactions and allowing for high-yield intermediate products. (5) Specifically in the production of triethylenediamine, because the intermediates of this reaction are prone to polymerization, the polymers generally flow with the gas flow. At the outlet position, the catalyst is more likely to form deposits with relatively large molecular weights. At this time, the catalyst removal device is adjusted to unload the catalyst and keep the catalyst bed in a highly active state. (6) The reactor of this invention can also be used for other strongly exothermic or strongly endothermic reactions. As long as the catalyst life of these reactions is greater than 24 hours, the reactor of this invention can be used to easily replace the catalyst and control the process parameters well, achieving the optimal reaction effect.

[0019] 2. This reactor is adiabatic, and inert gas can be added to the reaction raw materials to adjust the temperature of the catalyst bed.

[0020] 3. Using the reactor of this invention, piperazine can be produced with high selectivity, and the yield of piperazine is greater than that of triethylenediamine (TDI) by more than 85%. Attached Figure Description

[0021] Figure 1 A schematic diagram of the radial reactor (the adjustable orifice plate is divided into 4 sections, which are not shown in the figure);

[0022] Figure 2 A schematic diagram showing the structure with the largest opening when the adjustable orifice plate coincides with the product's air outlet opening.

[0023] Figure 3 Schematic diagram of the structure when the gap between the adjustable orifice plate and the product's air outlet is at its minimum;

[0024] Figure 4 Schematic diagram of the connection track between the adjustable orifice plate and the reactor inner shell;

[0025] Detailed description of the reactor structure: 1. Product gas collection port, 2. Reactor outer shell, 3. Reactor inner shell, 4. Gate valve B, 5. Feed three-way valve, 6. Gate valve A, 7. Catalyst inlet, 8. Intermediate silo, 9. Raw material gas diversion pipe, 10. Adjustable orifice plate, 11. Raw material gas inlet, 12. Catalyst discharge hopper, 13. Gate valve C, 14. Gate valve D, 15. Catalyst discharge port, 16. Discharge three-way valve. Detailed Implementation

[0026] The utility model will be described in detail below in combination with the drawings and specific embodiments, but the protection scope of the utility model is not limited to the following embodiments.

[0027] The reactor operating method is as follows:

[0028] 1. Replacing new catalyst (from catalyst inlet): opening the plug valve A, loading the catalyst into the intermediate bin, closing the catalyst inlet plug valve A, vacuumizing and replacing with nitrogen three times, opening the plug valve B connected with the reactor, loading the catalyst into the reactor, then closing the plug valve B, vacuumizing and replacing the intermediate bin with nitrogen three times for the next loading of catalyst.

[0029] 2. Unloading the deactivated catalyst (from catalyst outlet): opening the plug valve C, loading the deactivated catalyst into the catalyst discharge hopper, closing the plug valve C, vacuumizing and replacing with nitrogen three times, opening the plug valve D to unload the catalyst, closing the plug valve D, and vacuumizing and replacing the intermediate bin with nitrogen three times for the next unloading of catalyst.

[0030] 3. Unloading the catalyst in different bed layers: adjusting the adjustable orifice plate to coincide with the outlet opening, unloading the deactivated catalyst outside the bed layer, after unloading, adjusting the adjustable orifice plate to the minimum gap with the outlet opening for the outlet mode.

[0031] 4. The raw material gas enters the reactor from the raw material gas inlet, the raw material flows through the catalyst bed for reaction, the product gas is formed from the product outlet, flows through the gap between the inner shell and the outer shell, and is collected by the gas collecting port.

Claims

1. A radial flow reactor for the production of piperazine coproduct triethylenediamine from ethylenediamine, characterized in that The radial flow reactor for producing piperazine and triethylene diamine by-product from ethylenediamine comprises a catalyst feeding channel, a catalyst discharging channel, a raw material gas feeding channel and a product gas discharging channel. The catalyst feeding channel is arranged at the upper end of the reactor, and the catalyst discharging channel is arranged at the lower end of the reactor. The raw material gas feeding channel comprises a feeding port arranged on the outer wall of the reactor and a shunt pipe arranged in the center of the reactor. The reactor radial vertical part shell comprises an outer shell and an inner shell. The product gas discharging channel comprises a product gas outlet arranged on the inner shell of the reactor and a gas collecting port arranged on the outer shell. A catalyst removal device is arranged between the inner shell and the outer shell for removing the catalyst of the deactivated bed layer.

2. The radial flow reactor for producing piperazine and triethylene diamine by-product from ethylenediamine according to claim 1, characterized in that: The catalyst feeding channel comprises a catalyst feeding port, a plug valve A, a plug valve B, a feeding tee valve and an intermediate bin. The catalyst discharging channel comprises a catalyst discharging port, a plug valve C, a plug valve D, a discharging tee valve and a catalyst discharging hopper. The shunt pipe of the raw material gas feeding channel is connected with the feeding port on the side, and the upper and lower ends are closed. A plurality of micro pores are arranged on the pipe wall of the shunt pipe. The raw material gas enters the shunt pipe through the feeding port, and then flows through the catalyst bed layer for reaction. The product gas overflows from the gas outlet of the inner shell, flows through the channel between the inner shell and the outer shell, and is collected by the gas collecting port.

3. The radial flow reactor for the production of piperazine coproduct triethylenediamine from ethylenediamine according to claim 1, characterized in that The catalyst removal device is an adjustable aperture plate which is tightly attached to the outer side of the inner shell and can move along the outer side of the inner shell.

4. The radial flow reactor for the production of piperazine coproducts triethylenediamine according to claim 1, characterized in that The product gas outlet is a uniformly distributed opening arranged on the inner shell. A plurality of uniformly distributed openings are arranged on the adjustable aperture plate. The opening distribution of the adjustable aperture plate corresponds to the position of the product gas outlet one by one, and the sizes are the same. Both are larger than the diameter of the catalyst particles. The adjustable aperture plate and the product gas outlet can form different pore sizes by adjustment. When the two openings are staggered to make the gap the smallest, it is the gas outlet mode. When the two openings are completely overlapped, the pore size is the largest, and the catalyst can be discharged.

5. The radial flow reactor for the production of piperazine coproducts triethylenediamine according to claim 1, characterized in that The adjustable aperture plate is divided into four sections along the longitudinal coordinate direction, and each section can be moved independently.

6. The radial flow reactor for the production of piperazine coproducts triethylenediamine according to claim 1, characterized in that The adjustable aperture plate is controlled and moved by an eccentric wheel, so as to be adjusted. The eccentric wheel is controlled manually, and the handle is arranged on the outer shell of the reactor.

Images