A catalyst discharging device and method for a synthesis reactor

Abstract

The present invention provides a catalyst unloading device and method for a synthesis reactor, wherein a negative pressure is formed by a fan, and a solid-gas mixing chamber, a separator and a dust collector are sequentially arranged along the airflow direction on the air path between the synthesis reactor and the air inlet of the fan; the solid-gas mixing chamber is a shell structure of an indoor cavity, and a tangential inlet of the separator is introduced through a discharge pipe in the middle of the front bottom end along the airflow direction in the cavity, and an adjusting air duct with an adjusting valve is formed in the middle of the rear bottom end, and the air volume can be adjusted by adjusting the opening of the adjusting valve, and the solid-gas mixing chamber leads out a plurality of particle suction pipes connected to the cavity and independent of each other from the peripheral wall, and each particle suction pipe is inserted into the catalyst bed in the tube from the top of the corresponding tube array and can move up and down in the tube array; the outlet of the separator is connected to the inlet of the dust collector through the air duct, and the outlet of the dust collector is connected to the air inlet of the fan through the air duct. The present invention is easy to implement and maintain, saves manpower and operation time, and reduces costs and improves efficiency.

Description

Technical Field

[0001] The invention relates to the technical field of chemical production, and more specifically to a device and method for discharging a catalyst from a synthesis reactor. Background Art

[0002] At present, the main industrial processes for synthesizing vinyl acetate are ethylene oxidation and acetylene. Due to the large heat effect of the reaction of synthesizing vinyl acetate by ethylene oxidation and acetylene, the vinyl acetate synthesis reactor is generally a tube-type fixed bed reactor. Zinc acetate / activated carbon catalyst is loaded in the tube to form a certain height stacked bed. The mixed gas of acetylene and acetic acid reacts under the action of the catalyst to generate vinyl acetate.

[0003] However, since the catalyst particles in the reaction tubes of the synthesis reactor are in a static state and have a low breakage rate, after a period of reaction, the catalyst particles inside the tubes are prone to coking and bridging. The internal space of the upper and lower heads of the reactor is small, and when it is impossible to unload all of the particles from the bottom of the reactor, the only way is to use a hose to enter the reactor tubes in a limited space and start to clear the blockage from the bottom. Therefore, each time the catalyst is replaced, there are problems such as long catalyst unloading time, poor construction environment, high labor intensity, and harm to the health of loading and unloading personnel. Summary of the invention

[0004] The present invention aims to solve the above technical problems at least to a certain extent. To this end, the present invention provides a catalyst unloading device and method for a synthesis reactor, which is easy to implement and maintain, saves manpower and operation time, reduces costs and improves efficiency.

[0005] To achieve the above object, the present invention adopts the following technical solution:

[0006] A catalyst discharging device for a synthesis reactor has the following structural features:

[0007] A negative pressure is formed by a fan, and a solid-gas mixing chamber, a separator and a dust collector are arranged in sequence along the air flow direction on the air path between the synthesis reactor and the air inlet of the fan;

[0008] The solid-gas mixing chamber is a shell structure of an indoor cavity, and a discharge port in the middle of the front bottom end is introduced into the tangential inlet of the separator through a discharge pipe along the airflow direction in the cavity, and a regulating air duct is formed in the middle of the rear bottom end, and multiple independent particle suction pipes connected to the cavity are led out from the peripheral wall, and the multiple particle suction pipes are divided into two groups symmetrically arranged on the left and right side walls of the solid-gas mixing chamber, and the particle suction pipe group on each side is divided into two upper and lower rows arranged at intervals, and the particle suction pipes in each row are distributed at equal intervals from front to back along the airflow direction. The material flow direction in the particle suction pipe and the airflow direction in the solid-gas mixing chamber are both forward, and the particle suction pipe is inclined to form an angle with the front-to-back central axis of the solid-gas mixing chamber; the rear end of the regulating air duct is exposed outside the solid-gas mixing chamber and is provided with a regulating valve, and extends in the solid-gas mixing chamber to the position aligned with the frontmost particle suction pipe, and the pipe section aligned with the area between the two adjacent frontmost particle suction pipes in the single-row particle suction pipe is a truncated cone structure formed by gradually contracting from the back to the front end;

[0009] The number of the particle suction pipes is set according to the number of tube arrays in the synthesis reactor, and each particle suction pipe is inserted into the catalyst bed in the tube array from the top of the corresponding tube array and can move up and down in the tube array;

[0010] The outlet of the separator is connected to the inlet of the dust collector through an air duct, and the outlet of the dust collector is connected to the air inlet of the fan through an air duct.

[0011] The structural characteristics of the present invention also lie in:

[0012] The wind volume of the fan is 2000m 3 / h.

[0013] The particle suction pipe is made of an antistatic hose, the outer diameter of which is 8-10 mm smaller than the inner diameter of the tube array of the synthesis reactor, and can extend into the bottom of the tube array.

[0014] The tube end of the particle suction tube inserted into the tube array is detachably connected with a stainless steel tube head, and the tube end of the stainless steel tube head is serrated.

[0015] The separator is a cyclone separator; the dust collector is a bag filter, and the filtering accuracy of the filter bag is 5 μm.

[0016] The ash outlet at the bottom of the separator and the ash outlet at the bottom of the dust collector are both provided with dust collecting bags.

[0017] The present invention also proposes a method for unloading a catalyst from a synthesis reactor, which is implemented using the above-mentioned catalyst unloading device for the synthesis reactor and is carried out in the following steps:

[0018] Step 1: Catalyst collection and mixing

[0019] Each particle suction tube is extended from the upper tube plate of the synthesis reactor into the catalyst bed in each tube array, and the fan is started, and the fan air volume is set to 2000m 3 / h, the device turns on the vacuum mode;

[0020] Each particle suction pipe is manually operated to move up and down in the corresponding array of pipes. The stainless steel pipe head is in direct contact with the catalyst bed. Under the action of negative pressure airflow, each particle suction pipe is used to dredge the coked granular catalyst and transport the catalyst particles to the solid-gas mixing chamber. All catalyst particles transported to the solid-gas mixing chamber through the particle suction pipe are evenly mixed in the solid-gas mixing chamber under the action of negative pressure airflow.

[0021] Step 2: Particle separation and dust collection

[0022] The catalyst particles evenly mixed in the solid-gas mixing chamber enter the separator from the tangential inlet through the discharge pipe under the action of negative pressure airflow, and the gas-solid separation is realized under the action of centrifugal force. The catalyst particles separated by the separator fall into the dust bag at the bottom of the separator for collection, and the gas carrying the catalyst powder is sent out through the outlet of the separator and sent into the dust collector through the air duct. The catalyst powder enters the dust bag of the dust collector for collection, and the clean gas is sent to the air inlet of the fan through the air duct through the outlet of the dust collector and discharged from the air outlet of the fan.

[0023] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0024] The present invention can simultaneously extract catalysts from multiple tubes in a synthesis reactor, replacing the original catalyst replacement method of the synthesis reactor, improving the catalyst replacement environment, avoiding environmental pollution, greatly shortening the replacement time, saving a lot of manpower and time, effectively improving the operation rate of a single synthesis reactor, and reducing the catalyst replacement cost;

[0025] The present invention can be modified on the basis of the original device, has low cost, and is convenient for front-line employees to maintain and use. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the process principle of the present invention;

[0027] Figure 2 1 is a schematic diagram of the front view structure of the solid-gas mixing chamber;

[0028] Figure 3 1 is a schematic diagram of the top view of the solid-gas mixing chamber;

[0029] Figure 4 It is a structural schematic diagram of a stainless steel pipe head.

[0030] In the figure, 1 is a synthesis reactor; 2 is a solid-gas mixing chamber; 3 is a discharge pipe; 4 is an adjusting air duct; 5 is a regulating valve; 6 is a particle suction pipe; 7 is a stainless steel pipe head; 8 is a sawtooth; 9 is a separator; 10 is a dust collector; 11 is a fan; and 12 is a dust bag. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0032] Please refer to Figures 1 to 4 The structure of the catalyst discharge device of the synthesis reactor of this embodiment is as follows:

[0033] Negative pressure is formed by the fan 11, and a solid-gas mixing chamber 2, a separator 9 and a dust collector 10 are sequentially arranged along the air flow direction on the air path between the synthesis reactor 1 and the air inlet of the fan 11;

[0034] The solid-gas mixing chamber 2 is a shell structure of an indoor cavity. The discharge port at the middle of the front bottom end is introduced into the tangential inlet of the separator 9 through the discharge pipe 3 along the airflow direction in the cavity. A regulating air duct 4 is formed in the middle of the rear bottom end. A plurality of independent particle suction pipes 6 connected to the cavity are drawn out from the peripheral wall. The plurality of particle suction pipes 6 are divided into two groups symmetrically arranged on the left and right side walls of the solid-gas mixing chamber 2. The particle suction pipe 6 group on each side is divided into two upper and lower columns arranged at intervals. The particle suction pipes 6 in each column are distributed at equal intervals front and back along the airflow direction. The material flow direction in the particle suction pipe 6 and the airflow direction in the solid-gas mixing chamber 2 are both forward. The particle suction pipe 6 is inclined and is between the front-to-back central axis of the solid-gas mixing chamber 2. An angle is formed; the rear end of the regulating air duct 4 is exposed outside the solid-gas mixing chamber 2 and is provided with a regulating valve 5, which extends in the solid-gas mixing chamber 2 to the position aligned with the frontmost particle suction pipe 6, and the pipe section aligned with the area between the two frontmost adjacent particle suction pipes 6 in the single-row particle suction pipe 6 is a truncated cone structure gradually contracted from the back to the front end; the solid-gas mixing chamber 2 adopts this unique structural form, which can accelerate the flow of solid and gas, and by adjusting the opening of the regulating valve 5 on the regulating air duct 4, the negative pressure air volume and pressure can be adjusted, so as to better transport the catalyst particles through negative pressure; for example, when the air force is insufficient, the opening of the regulating valve 5 can be adjusted to be large, and when the air force is too large, the opening of the regulating valve 5 can be adjusted to be small;

[0035] The number of the particle suction pipes 6 is set in accordance with the number of tube arrays in the synthesis reactor 1. Each particle suction pipe 6 is inserted into the catalyst bed in the tube array from the top of the corresponding tube array and can move up and down in the tube array.

[0036] The outlet of the separator 9 is connected to the inlet of the dust collector 10 through the air duct, and the outlet of the dust collector 10 is connected to the air inlet of the fan 11 through the air duct.

[0037] In the specific implementation, the corresponding structural settings also include:

[0038] The air volume of fan 11 is 2000m 3 / h.

[0039] The particle suction pipe 6 is made of an antistatic hose, and its outer diameter is 8-10 mm smaller than the inner diameter of the tube array of the synthesis reactor 1, and can extend into the bottom of the tube array.

[0040] The end of the particle suction pipe 6 inserted into the tube array is detachably connected to a stainless steel pipe head 7. The end of the stainless steel pipe head 7 is in the shape of a sawtooth 8. Each sawtooth 8 is evenly spaced along the circumferential direction, and the interval between two adjacent sawtooths 8 is 90 degrees.

[0041] The separator 9 is a cyclone separator 9 based on the centrifugal separation principle; the dust collector 10 is a bag dust collector, using a Metas filter bag, and the filtration accuracy of the filter bag is 5 μm.

[0042] The ash outlet at the bottom of the separator 9 and the ash outlet at the bottom of the dust collector 10 are both provided with dust collecting bags 12 .

[0043] The device includes two units: catalyst collection and mixing and particle separation and dust collection, among which:

[0044] The catalyst collection and mixing unit uses each particle suction pipe 6 to simultaneously suck out the catalyst particles in each array of tubes and transport them to the solid-gas mixing chamber 2 for mixing, which greatly shortens the construction progress and improves the efficiency of catalyst particle discharge;

[0045] The particle separation and dust collection unit is to pass the catalyst particles mixed in the solid-gas mixing chamber 2 and output through the separator 9 and the dust collector 10 in sequence, and collect the catalyst particles into the dust bags 12 at the bottom of the separator 9 and the dust collector 10. Ton bags can be set at the bottom of the separator 9 and the dust collector 10, and the catalysts collected in the two dust bags 12 can be intermittently discharged into the ton bags below.

[0046] The embodiment of the present invention also provides a method for unloading a catalyst from a synthesis reactor, which is implemented using the above-mentioned catalyst unloading device for the synthesis reactor and is carried out in the following steps:

[0047] Step 1: Catalyst collection and mixing

[0048] Each particle suction pipe 6 extends from the upper tube plate of the synthesis reactor 1 into the catalyst bed in each tube array, and the fan 11 is started, and the air volume of the fan 11 is set to 2000m 3 / h, the device turns on the vacuum mode;

[0049] Each particle suction pipe 6 is manually operated to move up and down in the corresponding array of pipes, and the stainless steel pipe head 7 is in direct contact with the catalyst bed. Under the action of the negative pressure airflow, each particle suction pipe 6 is used to dredge the coked granular catalyst, and at the same time, the catalyst particles are transported to the solid-gas mixing chamber 2; all the catalyst particles transported to the solid-gas mixing chamber 2 through the particle suction pipe 6 are evenly mixed in the solid-gas mixing chamber 2 under the action of the negative pressure airflow;

[0050] Step 2: Particle separation and dust collection

[0051] The catalyst particles evenly mixed by the solid-gas mixing chamber 2 enter the separator 9 from the tangential inlet through the discharge pipe under the action of the negative pressure airflow, and swirl in the separator 9, so that the large particles of catalyst with large inertial centrifugal force collide with the inner wall of the separator 9, decelerate and fall into the dust bag 12 at the cone bucket at the bottom of the separator 9 for collection, thereby achieving the effect of gas-solid separation. The catalyst particles separated by the separator 9 fall into the dust bag 12 at the bottom of the separator 9 for collection, and the gas carrying the fine catalyst powder is sent out through the outlet of the separator 9 and sent into the dust collector 10 through the air duct. The fine catalyst powder enters the dust bag 12 of the dust collector 10 for collection, and the clean gas is sent to the air inlet of the fan 11 through the air duct through the outlet of the dust collector 10 and discharged from the air outlet of the fan 11.

[0052] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A catalyst discharging device for a synthesis reactor, characterized in that: A negative pressure is formed by a fan, and a solid-gas mixing chamber, a separator and a dust collector are arranged in sequence along the air flow direction on the air path between the synthesis reactor and the air inlet of the fan; The solid-gas mixing chamber is a shell structure of an indoor cavity, and a discharge port in the middle of the front bottom end is introduced into the tangential inlet of the separator through a discharge pipe along the airflow direction in the cavity, and a regulating air duct is formed in the middle of the rear bottom end, and multiple independent particle suction pipes connected to the cavity are led out from the peripheral wall, and the multiple particle suction pipes are divided into two groups symmetrically arranged on the left and right side walls of the solid-gas mixing chamber, and the particle suction pipe group on each side is divided into two upper and lower rows arranged at intervals, and the particle suction pipes in each row are distributed at equal intervals from front to back along the airflow direction. The material flow direction in the particle suction pipe and the airflow direction in the solid-gas mixing chamber are both forward, and the particle suction pipe is inclined to form an angle with the front-to-back central axis of the solid-gas mixing chamber; the rear end of the regulating air duct is exposed outside the solid-gas mixing chamber and is provided with a regulating valve, and extends in the solid-gas mixing chamber to the position aligned with the frontmost particle suction pipe, and the pipe section aligned with the area between the two adjacent frontmost particle suction pipes in the single-row particle suction pipe is a truncated cone structure formed by gradually contracting from the back to the front end; The number of the particle suction pipes is set according to the number of tube arrays in the synthesis reactor, and each particle suction pipe is inserted into the catalyst bed in the tube array from the top of the corresponding tube array and can move up and down in the tube array; The outlet of the separator is connected to the inlet of the dust collector through an air duct, and the outlet of the dust collector is connected to the air inlet of the fan through an air duct.

2. The catalyst discharging device for the synthesis reactor according to claim 1, characterized in that: The wind volume of the fan is 2000m 3 / h.

3. The catalyst discharging device for the synthesis reactor according to claim 1, characterized in that: The particle suction pipe is made of an antistatic hose, the outer diameter of which is 8-10 mm smaller than the inner diameter of the tube array of the synthesis reactor, and can extend into the bottom of the tube array.

4. The catalyst discharging device for the synthesis reactor according to claim 1, characterized in that: The tube end of the particle suction tube inserted into the tube array is detachably connected with a stainless steel tube head, and the tube end of the stainless steel tube head is serrated.

5. The catalyst discharging device for the synthesis reactor according to claim 1, characterized in that: The separator is a cyclone separator; the dust collector is a bag filter, and the filtering accuracy of the filter bag is 5 μm.

6. The catalyst discharging device for the synthesis reactor according to claim 1, characterized in that: The ash outlet at the bottom of the separator and the ash outlet at the bottom of the dust collector are both provided with dust collecting bags.

7. A method for unloading a catalyst from a synthesis reactor, characterized in that: The method is implemented by using the catalyst discharge device of the synthesis reactor according to any one of claims 1 to 6, and is carried out according to the following steps: Step 1: Catalyst collection and mixing Each particle suction tube is extended from the upper tube plate of the synthesis reactor into the catalyst bed in each tube array, and the fan is started, and the fan air volume is set to 2000m 3 / h, the device turns on the vacuum mode; Each particle suction pipe is manually operated to move up and down in the corresponding array of pipes. The stainless steel pipe head is in direct contact with the catalyst bed. Under the action of negative pressure airflow, each particle suction pipe is used to dredge the coked granular catalyst and transport the catalyst particles to the solid-gas mixing chamber. All catalyst particles transported to the solid-gas mixing chamber through the particle suction pipe are evenly mixed in the solid-gas mixing chamber under the action of negative pressure airflow. Step 2: Particle separation and dust collection The catalyst particles evenly mixed in the solid-gas mixing chamber enter the separator from the tangential inlet through the discharge pipe under the action of negative pressure airflow, and the gas-solid separation is realized under the action of centrifugal force. The catalyst particles separated by the separator fall into the dust bag at the bottom of the separator for collection, and the gas carrying the catalyst powder is sent out through the outlet of the separator and sent into the dust collector through the air duct. The catalyst powder enters the dust bag of the dust collector for collection, and the clean gas is sent to the air inlet of the fan through the air duct through the outlet of the dust collector and discharged from the air outlet of the fan.

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