CN206304709U - A slurry or liquid catalyst feeding device - Google Patents

Abstract

The utility model provides a thick liquid or liquid catalyst feed arrangement, a serial communication port, include: a catalyst preparation tank provided with an inlet and an outlet; the feeding metering unit is connected with the outlet of the catalyst preparation tank; the conveying unit is connected with the outlet of the feeding metering unit; and the gas distribution unit is connected with the outlet end of the conveying unit and converged and then connected with the post-treatment unit, and the catalyst from the conveying unit and the gas from the gas distribution unit are mixed and then output to the post-treatment unit.

Description

A slurry or liquid catalyst feeding device

technical field

The utility model relates to a slurry or liquid catalyst feeding device, which can be widely used in olefin polymerization reaction technology.

Background technique

Slurry or liquid catalyst is a catalyst used in the gas phase ethylene polymerization process, it is a suspension or solution state catalyst dispersed in a viscous liquid, the solid content is about 20%, and the particle diameter of the solid is less than 50 microns. Compared with silica gel-supported solid catalysts, slurry catalysts have the advantages of high activity, low cost, and good quality of polymerization products, and are likely to replace traditional solid catalysts.

The polymerization process requires the slurry or liquid catalyst to be fed into the polymerization reactor in a continuously stable and precisely controlled extremely small flow rate, otherwise it will cause unstable polymerization reaction, resulting in product quality fluctuations or reactor agglomeration.

The slurry or liquid catalyst feeding device provided in Chinese patent 02269754 mainly includes a catalyst feeding tank, a micro feeder connected to it, a hydraulic oil control system and an atomizing nozzle. Although the feeding system can realize a stable and continuous slurry or liquid catalyst However, there are also problems such as the catalyst is easy to settle in the delivery pipeline and the concentration changes, which affects the accuracy of the feeding, and then affects the stability of the polymerization reaction.

A set of slurry feeding device is disclosed in CN200510102423.5, which includes a slurry catalyst tank, a delivery pump and at least one six-way valve and metering tube. When feeding is required, the position of the six-way valve is changed once, and the catalyst in the metering tube is absorbed into the in the polymerization system. By operating the six-way valve, stable, uniform and precise feeding of slurry or liquid catalyst can be realized.

CN200820060332 discloses a viscous slurry precision metering and feeding device, the device is sequentially provided with viscous slurry mother liquor feeding tank, pre-mixer, first additive a reaction buffer tank, pre-mixer, second additive b reaction from upstream to downstream The buffer tank and the corresponding heat tracing circuit, its feeding method and device can control the slurry concentration, so that the catalyst or other viscous slurry and other reactants can be fed accurately and quantitatively.

Utility model content

The purpose of the utility model is designed to realize continuous, stable and quantitative feeding of slurry or liquid catalyst.

In order to achieve the above object, the slurry or liquid catalyst feeding device provided by the utility model includes:

Catalyst preparation tank, equipped with import and export;

A feed metering unit is connected with the outlet of the catalyst preparation tank;

A delivery unit connected to the outlet of the feed metering unit;

The gas distribution unit is connected to the post-processing unit after meeting the outlet end of the delivery unit, and the catalyst from the delivery unit is mixed with the gas from the gas distribution unit and then output to the post-processing unit.

In the slurry or liquid catalyst feeding device, the feed metering unit further includes: two volumetric flowmeters connected in parallel, and two pipelines are arranged on the upper part of each volumetric flowmeter, one of which is the first outlet The first discharge line is connected to the outlet at the bottom of the catalyst preparation tank, the other line is connected to the upper part of the catalyst preparation tank to form the pressure balance line, and the lower part of the volumetric flowmeter is provided with There is a second discharge pipeline, and the two second discharge pipelines meet and are connected to the delivery unit.

In the slurry or liquid catalyst feeding device, the delivery unit further includes a delivery pump and a back pressure valve, the outlet of the delivery pump is connected to a third discharge pipeline, and the third discharge pipeline is connected to the post-processing unit , the third discharge pipeline is provided with a back pressure valve, a first pressure gauge, and a second pressure gauge, the first pressure gauge is set between the delivery pump and the back pressure valve, and the second pressure gauge is set between the back pressure Between the valve and the aftertreatment unit.

In the slurry or liquid catalyst feeding device, the gas distribution unit further includes a gas supply source, a gas distribution line connected to the gas supply source, and sequentially arranged on the gas distribution line along the gas flow direction. The pressure reducing valve and the gas flow meter are connected with a third pressure gauge between the pressure reducing valve and the gas flow meter.

In the slurry or liquid catalyst feeding device, the gas distribution line is connected to the third discharge pipeline, and the connection between the gas distribution line and the third discharge pipeline is located after the second pressure gauge. A one-way valve is arranged on the gas distribution line, and the one-way valve is arranged at the end of the gas distribution line.

In the slurry or liquid catalyst feeding device, the post-processing unit is a fluidized bed reactor, and an atomizer is arranged in the fluidized bed reactor.

In the slurry or liquid catalyst feeding device, a stirring device is also provided in the catalyst preparation tank.

In the slurry or liquid catalyst feeding device, the catalyst preparation tank is also provided with a liquid level detection device.

In the slurry or liquid catalyst feeding device, electromagnetic valves are provided on the two first discharge pipelines, the pressure balance line, and the two second discharge pipelines.

The beneficial effects of the utility model:

The slurry or liquid catalyst feeding device of the utility model can be widely used in the olefin polymerization process, especially in the gas phase polyolefin polymerization process, such as the well-known Unipol polyethylene process, Inovene polypropylene process, etc. in this industry. It has the advantages of high feeding precision, wide adjustment range of feeding amount, continuous and stable feeding, etc., and low investment cost, which can well meet the needs of various occasions from polymerization pilot tests to industrial applications.

Description of drawings

Figure 1 is a schematic diagram of the structure of a slurry or liquid catalyst feeding device.

Figure 2 is a schematic diagram of the structure of the feed metering unit.

Wherein reference sign is:

Catalyst preparation tank 1

Liquid level detection device 11

Stirring device 12

motor 13

Volume flow meter 2A

Volume flow meter 2B

First discharge line 21

Second discharge line 22

Pressure balance line 23

Solenoid valve 15A

Solenoid valve 15B

Solenoid valve 15C

Solenoid valve 15D

Solenoid valve 15E

Solenoid valve 15F

transfer pump 3

Third discharge line 31

Back pressure valve 311

First pressure gauge 312

Second pressure gauge 313

Air supply 4

Gas distribution lines 41

Pressure reducing valve 42

Gas Flow Meter 43

Third pressure gauge 44

Check valve 45

Fluidized bed reactor 5

Atomizer 51

detailed description

The utility model provides a slurry or liquid catalyst feeding device, comprising: a catalyst preparation tank 1, a feed metering unit, a delivery unit, a gas distribution unit, and a post-processing unit.

Catalyst preparation tank 1 is provided with a stirring device 12, such as a stirring paddle, the upper part of the stirring paddle is connected to a motor 13, and a liquid level detection device 11 is installed on the catalyst preparation tank 1, and the outlet of the catalyst preparation tank 1 is located at the bottom of the tank. The outlet of tank 1 is connected to a feed metering unit.

The feed metering unit includes two volumetric flowmeters (2A, 2B) connected in parallel, and each volumetric flowmeter is provided with two pipelines on the upper part, one of which is the first discharge pipeline 21, and the other is the pressure balance line 23, The first discharge pipeline 21 is connected to the outlet at the bottom of the catalyst preparation tank 1, and the other pipeline communicates with the top of the catalyst preparation tank 1 to form a pressure balance line 23. The bottom of the volumetric flowmeter is provided with a second discharge pipeline 22, two The second discharge pipeline 22 is connected to the conveying unit after meeting. The first discharge pipeline 21 , the pressure balance line 23 and the second discharge pipeline 22 are all equipped with solenoid valves.

The transfer unit connection includes a transfer pump 3 and a back pressure valve 311, the outlet of the transfer pump 3 is connected to the third discharge pipeline 31, the third discharge pipeline 31 is connected to the post-processing unit, and the third discharge pipeline 31 is provided with a back pressure valve 311 , the first pressure gauge 312, the second pressure gauge 313, the first pressure gauge 312 is set between the delivery pump 3 and the back pressure valve 311, the second pressure gauge 313 is set between the back pressure valve 311 and the post-processing unit, in the gas distribution A one-way valve 45 is provided on the line 41, and the one-way valve 45 is arranged at the end of the gas distribution line 41, and the third discharge line 31 is connected to a gas distribution unit.

The gas distribution unit comprises a gas supply source 4, a gas distribution line 41 connected to the gas supply source 4, a pressure reducing valve 42, a gas flowmeter 43 are arranged on the gas distribution line 41 along the gas flow direction, and a pressure reducing valve 42 A third pressure gauge 44 is connected to the gas flow meter 43 . The gas distribution line 41 is connected with the third discharge pipeline 31 of the gas distribution unit, and the connection between the gas distribution line 41 and the third discharge pipeline 31 is located behind the second pressure gauge 313, and the catalyst from the delivery unit is connected with the gas distribution unit. After the gas is mixed, it is output to the post-processing unit.

The aftertreatment unit is a fluidized bed reactor, and an atomizer is arranged in the fluidized bed reactor.

The catalyst of the utility model can be a slurry catalyst or a liquid catalyst, and the "serous catalyst" referred to refers to a liquid containing small solid particles, and the "liquid catalyst" refers to a liquid not containing small solid particles. The weight percentage of solids in the general slurry catalyst is less than 75%.

In the above-mentioned feeding device, the purpose of the utility model is achieved in this way: when feeding is required, the slurry or liquid catalyst passes through the volume flow meter under the action of the delivery pump 3, and after passing through the back pressure valve 311 and the pressure gauge, The conveying nitrogen connected to the pressure gauge is sent to the post system, such as the polymerization reaction system. Therefore, continuous, stable and precise quantitative feeding of slurry or liquid catalyst is realized.

In the catalyst preparation tank 1, a stirring device is optionally added to make the feed of the catalyst more uniform, especially for the slurry catalyst, setting the stirring device 12 can avoid the sedimentation of the catalyst in the tank. The catalyst preparation tank 1 and the feed pipeline (not shown in the figure) should be equipped with electric heating wires, and an insulation layer should be provided on the outside, which has strict requirements on the heating temperature, and is also to avoid the sedimentation of the slurry catalyst in the tank and pipeline . In addition, the catalyst preparation tank 1 can also use the liquid level detection device 11 commonly used in this industry, specifically glass, differential pressure, magnetic float, ultrasonic, capacitor and other types.

The delivery pump 3 can adopt various types of liquid delivery pumps used in the industry, such as peristaltic pumps, diaphragm pumps, screw pumps, or plunger pumps. The pressure difference between the pressure set by the back pressure valve 311 and the reactor pressure is 0.1-1.0 MPa, which can be adjusted arbitrarily according to the concentration, activity and polymerization reaction status of the catalyst.

The pressure difference between the pressure set by the decompression valve 42 and the reactor pressure is 0.1-1.0 MPa, which can be adjusted arbitrarily according to the concentration, activity and polymerization reaction status of the catalyst.

The value set by the gas flow meter 43 is 0.5-15 Nm ³ /h, which can be adjusted arbitrarily according to the concentration, activity and polymerization reaction status of the catalyst.

The following specific examples are given to further illustrate:

Example 1

Figure 1 is a slurry or liquid catalyst feeding device for supplying slurry or liquid catalyst to a polymerization system. In the gas distribution unit, a pressure gauge is connected between the pressure reducing valve and the gas flow meter on the gas distribution line 41. The gas distribution unit is connected to the delivery unit and then connected to the post-processing unit (fluidized bed reactor, atomizer). A one-way valve 45 is connected to the end of the gas distribution unit, the atomizer is located inside the fluidized bed reactor, and the gas source can be nitrogen gas source.

When feeding is required, set the pressure reducing valve and the value of the gas flow meter according to the conditions of the polymerization reaction system, then start the delivery pump, adjust the feed amount of the catalyst by adjusting the delivery pump itself, according to the concentration, activity and polymerization of the catalyst According to the reaction conditions, adjust the back pressure valve appropriately, and send nitrogen to continuously send the slurry or liquid catalyst to the post-processing unit.

Example 2

Figure 2 is a feed metering unit for slurry or liquid catalyst, which consists of two volumetric flowmeters and a solenoid valve group. The size of the volume flowmeter can be changed according to the feed rate, and the liquid level measurement and the solenoid valve form a cascade. When the liquid level of the volume flowmeter 16A drops to a low setting value, the solenoid valve 15E is closed, and the solenoid valves 15B and 15F are opened at the same time; The liquid level of positive displacement flowmeter 16A rises to the high setting value, and solenoid valve 15B closes. The principle of flowmeter 16B is the same as that of 16A, and is in an alternate operating state with 16A. Solenoid valves 15A and 15C are always in the open state, and are in communication with the catalyst configuration tank to prevent the volumetric flowmeter from holding pressure. By measuring the time it takes for the volumetric flowmeter level to drop from the high set point to the low set point, the catalyst feed rate can be accurately calculated while ensuring that the catalyst feed is always in a continuous state.

The slurry or liquid catalyst feeding device of the utility model can be widely used in the olefin polymerization process, especially in the gas phase polyolefin polymerization process, such as the well-known Unipol polyethylene process, Inovene polypropylene process, etc. in this industry. It has the advantages of high feeding precision, wide adjustment range of feeding amount, continuous and stable feeding, etc., and low investment cost, which can well meet the needs of various occasions from polymerization pilot tests to industrial applications.

Claims (9)

1. A slurry or liquid catalyst feeding device, characterized in that, comprising: Catalyst preparation tank, equipped with import and export; A feed metering unit is connected with the outlet of the catalyst preparation tank; A delivery unit connected to the outlet of the feed metering unit; The gas distribution unit is connected to the post-processing unit after meeting the outlet end of the delivery unit, and the catalyst from the delivery unit is mixed with the gas from the gas distribution unit and then output to the post-processing unit. 2. The slurry or liquid catalyst feeding device as claimed in claim 1, characterized in that, the feed metering unit further comprises: two volumetric flowmeters connected in parallel, each volumetric flowmeter top is provided with Two pipelines, one of which is the first discharge pipeline and the other is the pressure balance line, the first discharge pipeline is connected to the outlet at the bottom of the catalyst preparation tank, and the other pipeline is connected to the upper part of the catalyst preparation tank to form the pressure balance line , the lower part of the volumetric flowmeter is provided with a second discharge pipeline, and the two second discharge pipelines are connected to the delivery unit after meeting. 3. The slurry or liquid catalyst feeding device as claimed in claim 1 or 2, characterized in that, the delivery unit further comprises a delivery pump and a back pressure valve, the outlet of the delivery pump is connected to the third discharge pipeline, and the The third discharge pipeline is connected to the post-processing unit, and the third discharge pipeline is provided with a back pressure valve, a first pressure gauge, and a second pressure gauge, and the first pressure gauge is arranged on the delivery pump and the back pressure Between the valves, the second pressure gauge is arranged between the back pressure valve and the post-processing unit. 4. The slurry or liquid catalyst feeding device as claimed in claim 3, wherein the gas distribution unit further comprises a gas supply source, a gas distribution line connected to the gas supply source, along the gas flow direction A pressure reducing valve and a gas flow meter are sequentially arranged on the gas distribution line, and a third pressure gauge is connected between the pressure reducing valve and the gas flow meter. 5. slurry or liquid catalyst feeding device as claimed in claim 4, is characterized in that, described gas distribution line is connected with described 3rd discharge pipeline, and described gas distribution line is connected with described 3rd discharge pipeline The connection is located after the second pressure gauge, and a one-way valve is arranged on the gas distribution line, and the one-way valve is arranged at the end of the gas distribution line. 6. The slurry or liquid catalyst feeding device according to claim 1, characterized in that, the post-processing unit is a fluidized bed reactor, and an atomizer is arranged in the fluidized bed reactor. 7. The slurry or liquid catalyst feeding device according to claim 1, characterized in that a stirring device is also provided in the catalyst preparation tank. 8. The slurry or liquid catalyst feeding device according to claim 1 or 7, characterized in that the catalyst preparation tank is also provided with a liquid level detection device. 9. The slurry or liquid catalyst feeding device according to claim 2, characterized in that electromagnetic valves are provided on the two first discharge pipelines, the pressure balance line and the two second discharge pipelines.