Device and method for dispensing catalysts for polyolefins

Abstract

The application discloses a kind of polyolefin catalyst's split charging device, including catalyst finished product tank and at least two catalyst split charging tank by distribution system communication, distribution system includes the first multi-pass switching valve group of controlling catalyst material flow direction and the second multi-pass switching valve group of controlling pressure release, and the catalyst flow port on adjacent two catalyst split charging tank is communicated by pipeline with sight glass;Second multi-pass switching valve group includes at least one flow pass;Each flow pass is respectively communicated with the emptying port on corresponding catalyst split charging tank by pipeline.Using the device to carry out catalyst split charging, by the cooperation of each pass in two switching valve groups and each catalyst split charging tank, flow pass and emptying port, combined with sight glass, can effectively avoid the safety risk of overpressure existing in the phenomenon of tank eruption generated in split charging process and split charging tank, while improving the accuracy of catalyst split charging, can be used for the distribution and split charging of catalyst.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of olefin polymerization, in particular to a catalyst dispensing device and method for polyolefin. BACKGROUND

[0002] The catalyst types used in the production process of polyethylene are Z-N catalyst, metallocene catalyst, Cr catalyst, non-metallocene catalyst, etc., which can produce different polyethylene products, such as butene copolymer polyethylene, octene copolymer polyethylene, ultra-high molecular weight polyethylene, very low density polyethylene, etc. With the rapid development of the polyethylene industry in recent years, the application of catalysts has achieved remarkable success. Combined with the polyethylene production process, polyethylene products that meet different use requirements can be produced. On the basis of continuously improving the production technology level, product quality and production scale of polyethylene, the production technology and research and development application of catalysts are also constantly innovating.

[0003] Before evaluating the application performance of the prepared polyethylene catalyst, product test data can be obtained through a small test polymerization device, and then a pilot production device is used to obtain device analysis operation data and product performance by using catalysts for market application. The research and development of catalysts aim to improve the production load of the device and broaden the product grade. Only a catalyst system with stable comprehensive performance can help the device to operate stably at high load and better produce high-value-added grades. Combined with the polyolefin production process, the performance of the catalyst is investigated by adjusting the hydrogen / ethylene molar ratio and the change of the alpha-olefin / ethylene molar ratio during the production of the target grade. The dry powder catalyst used in ethylene polymerization is the key to the entire polyethylene production line. Accurate catalyst dosage and ratio can improve the efficiency of polyethylene production research. For devices with multiple polyethylene small test and pilot polymerization research, catalysts are distributed in different polyethylene reactors and cannot be used interchangeably, so the catalysts need to be distributed to the corresponding storage tanks for use. The polyethylene dry powder catalyst dispensing tank is a pressure vessel used for small-batch dispensing and storage of large-volume dry powder catalyst products in the finished product tank. The dispensing tank is connected with a catalyst feed port, a nitrogen port, a vent port, a pressure gauge, a valve and other related accessories on the top of the tank. A weighing scale is provided at the bottom of the tank body. During dispensing, the dispensing tank and the conveying pipeline are replaced with nitrogen, and then the feeding is carried out through the feeding pipeline. When the tank pressure and mass reach the set value, the relevant valves are closed, and the dispensing is completed. However, in actual operation, before determining that the feeding is completed and closing the valves, the catalyst has already emerged from the venting pipeline, causing the phenomenon of tank overflow, which in turn causes product loss, increases the difficulty of cleaning and pollutes the environment. At present, there is no literature and technology to show how to effectively distribute the polyethylene dry powder catalyst, and no industry standards or specifications have been formed. Therefore, it is urgent to develop a dry powder catalyst material dispensing device and method for olefin polymerization and its application.

[0004] As disclosed in Chinese patent document CN108017733B, a catalyst material distribution device for olefin polymerization, a distribution method and application thereof are disclosed. The catalyst distribution device comprises a catalyst storage tank, a catalyst feed pump and a catalyst material distribution system connected in sequence. The catalyst material distribution system comprises a multi-pass switching valve group for controlling the flow direction of the catalyst material and a controller electrically connected to the multi-pass switching valve group. The multi-pass switching valve group comprises a feed port, a flushing port and a discharge port. The total number of the feed port and the flushing port is equal to the number of the discharge port. The catalyst material can be divided into multiple streams according to a predetermined ratio and enter the downstream production line main polymerization reactor respectively. By periodically switching the flow direction, a parallel production mode of multiple polyolefin production lines sharing one set of catalyst storage and feeding device can be realized. However, the distribution device is suitable for the distribution of liquid phase catalysts, and the catalysts are prone to sedimentation in the conveying pipeline during the distribution process, which leads to changes in the concentration of the catalysts and other problems, thereby affecting the accuracy of the catalyst distribution and feeding, affecting the stability of the polymerization reaction, and once the mechanical seal of the catalyst feed pump leaks, it will cause great harm to personal safety. At the same time, the catalyst distribution system is more suitable for the feeding of catalysts and is not suitable for the distribution and storage of catalysts.

[0005] Chinese patent document CN205745269U discloses a benzene hydrogenation catalyst combination split charging tank. The benzene hydrogenation catalyst combination split charging tank comprises a main split charging tank and a secondary split charging tank. Nitrogen pipelines, catalyst feeding pipelines and emptying pipelines are arranged on the main split charging tank body and the secondary split charging tank body. The main split charging tank and the secondary split charging tank are connected through a soft connection pipeline. However, the benzene hydrogenation catalyst combination split charging tank cannot directly observe whether the tank is overflowing during the catalyst split charging process. The catalyst in the main split charging tank will inevitably lose mass during the pressure discharge process. The weight of the catalyst in the tank cannot be accurately measured. In addition, during the process of feeding the catalyst from the main split charging tank to the secondary split charging tank, the pressure will inevitably exceed the normal pressure, which poses a safety risk.

[0006] Chinese patent document CN216806694U discloses a magnesium-titanium polyethylene catalyst tank discharge mechanism. The magnesium-titanium polyethylene catalyst tank discharge mechanism comprises a storage tank body, a height adjusting device, a discharge device and a sealing device. The storage tank body comprises a feeding port and a discharge port. The height adjusting device comprises a support frame. The discharge device comprises an electric valve arranged at the discharge port. A discharge pipe is arranged at the bottom end of the discharge port. A scattering disc is fixedly arranged at one end of the discharge pipe. A driving device is arranged at the other end of the discharge pipe. The design of the hydraulic cylinder and the guide rod facilitates the adjustment of the height of the storage tank body and the discharge of the catalyst. However, the device drives the catalyst to flow in the discharge pipe by arranging a nitrogen compressor and a nitrogen buffer tank at one end of the discharge pipe and blowing compressed nitrogen in the discharge pipe to avoid the congestion of the catalyst in the discharge pipe. This process can only ensure that the finished tank is prevented from being affected by water vapor and dust and other pollutants. In addition, the equipment operation is complex and not suitable for the distribution and split charging of the catalyst.

[0007] Chinese patent document CN203346317 U discloses a special device for adding catalyst in polymerization reaction of terpene resin production, which comprises a feeding tank and a nitrogen buffer tank, a discharge butterfly valve is arranged at the discharge port of the bottom of the feeding tank, a closable catalyst feeding port, a vent valve, a pressure gauge and a nitrogen input port are arranged at the top of the feeding tank, the gas output end of the nitrogen buffer tank is connected with the nitrogen input port of the feeding tank through an adjusting valve and a gas inlet valve; a sight glass cylinder is arranged at the output end of the discharge butterfly valve to form an external port, so that the catalyst feeding speed and amount can be conveniently observed through the sight glass cylinder; a transparent scale is arranged on the sidewall of the feeding tank to conveniently observe the catalyst storage amount in the feeding tank; the connection from the catalyst feeding port of the feeding tank to the reaction kettle constitutes a fully-closed reaction system. However, the sight glass cylinder in the device is only used for observing the catalyst feeding speed and amount, and the transparent scale on the sidewall of the feeding tank is used for observing the catalyst storage amount in the feeding tank, so that the catalyst storage amount is not accurate. SUMMARY

[0008] The present application aims to provide a catalyst dispensing device and method for polyolefins, which can be used for dispensing and distributing catalysts.

[0009] To achieve the above-mentioned purpose, the present application provides a catalyst dispensing device for polyolefins, which comprises a catalyst product tank and at least two catalyst dispensing tanks, and the catalyst product tank and each catalyst dispensing tank are connected through a distribution system.

[0010] The distribution system comprises a first multi-way switching valve group for controlling the flow direction of catalyst and a second multi-way switching valve group for controlling pressure relief.

[0011] The top of each catalyst dispensing tank is provided with a catalyst inlet, a vent and at least one catalyst flow port; the top of the catalyst product tank is provided with a nitrogen inlet, a catalyst feeding port and a safety valve vent, and the bottom is provided with a discharge port.

[0012] The first multi-way switching valve group comprises a catalyst feeding port and at least two catalyst discharge ports, the number of catalyst discharge ports is the same as the number of catalyst dispensing tanks, each catalyst discharge port is connected with the catalyst inlet of the corresponding catalyst dispensing tank through a pipeline; and the catalyst flow ports of adjacent two catalyst dispensing tanks are connected through a pipeline with a sight glass.

[0013] The second multi-channel switching valve assembly includes an inlet, an outlet, and at least one flow port; the inlet is connected via a pipeline to the discharge port at the bottom of the catalyst finished product tank; the outlet is connected via a pipeline to the catalyst inlet of the first multi-channel switching valve assembly; the number of flow ports is no more than the number of catalyst dispensing tanks, and each flow port is connected via a pipeline to the vent port on the corresponding catalyst dispensing tank.

[0014] Optionally, in the dispensing device for the catalyst for polyolefins provided by the present invention, the first multi-channel switching valve group and the second multi-channel switching valve group are electrically connected to the corresponding controller or manually controlled according to the catalyst feed rate.

[0015] Optionally, in the catalyst dispensing device for polyolefins provided by the present invention, each catalyst dispensing tank is provided with a pneumatic vibrating hammer.

[0016] Optionally, in the dispensing device for the catalyst for polyolefins provided by the present invention, each sight glass is provided with a flow control valve on the pipeline between the catalyst flow port on the corresponding catalyst dispensing tank; preferably, the flow control valve is located at the catalyst flow port on the catalyst dispensing tank, and the number of catalyst flow ports on the catalyst dispensing tank is the same as the number of flow control valves, which is not limited in specific terms, but preferably 1-2.

[0017] Optionally, in the dispensing device for the catalyst for polyolefins provided by the present invention, the first multi-channel switching valve group is a four-way valve containing one catalyst inlet and three catalyst outlets; the second multi-channel switching valve group is a four-way valve containing one inlet, one outlet and two flow ports.

[0018] Optionally, in the polyolefin catalyst dispensing device provided by the present invention, a second control valve is provided on the pipeline between each catalyst outlet in the first multi-channel switching valve group and the catalyst inlet on the corresponding catalyst dispensing tank. Preferably, the second control valve is located at the catalyst inlet on the catalyst dispensing tank.

[0019] Optionally, in the polyolefin catalyst dispensing device provided by the present invention, a first control valve is provided on the pipeline between the inlet of the second multi-channel switching valve group and the discharge port at the bottom of the catalyst finished product tank. Preferably, the first control valve is located at the discharge port at the bottom of the catalyst finished product tank.

[0020] Optionally, in the catalyst dispensing device for polyolefins provided by the present invention, a pressure detection device is provided on the catalyst dispensing tank farthest from the nitrogen storage tank, and preferably, a pressure detection device is provided on each of the catalyst dispensing tanks.

[0021] Optionally, in the polyolefin catalyst dispensing device provided by the present invention, the polyolefin catalyst dispensing device further includes a discharge tank; the vent on each catalyst dispensing tank is connected to the discharge tank via a pipeline containing a vent valve, preferably the vent valve is located at the vent on the catalyst dispensing tank.

[0022] Optionally, in the catalyst dispensing device for polyolefins provided by the present invention, the catalyst dispensing tank closest to the nitrogen storage tank is provided with a nitrogen inlet; preferably, each catalyst dispensing tank is provided with a nitrogen inlet.

[0023] Optionally, in the polyolefin catalyst dispensing device provided by the present invention, the catalyst finished product tank is equipped with a stirring device.

[0024] Optionally, in the dispensing device for the polyolefin catalyst provided by the present invention, each of the pipelines is made of stainless steel. By using stainless steel pipelines, problems such as rupture due to lack of pressure resistance of conventional PVC or polyurethane pipelines can be prevented. The specific length and diameter of each pipeline are determined by the distance between the devices and the amount of catalyst, preferably 1 / 8 to 1 / 2 inch pipelines.

[0025] The present invention also provides a method for dispensing a catalyst for polyolefins, wherein the above-mentioned dispensing device for the catalyst for polyolefins is used for dispensing.

[0026] Optionally, the present invention also provides a method for dispensing a catalyst for polyolefins, comprising the following steps:

[0027] The air in the dispensing device for the catalyst of the polyolefin is completely replaced with nitrogen;

[0028] The catalyst in the finished catalyst tank is sequentially fed into the corresponding catalyst dispensing tank through pipelines via the discharge port at the bottom of the finished catalyst tank, the inlet of the second multi-channel switching valve group and the outlet of the second multi-channel switching valve group, the catalyst inlet in the first multi-channel switching valve group and at least one catalyst outlet in the first multi-channel switching valve group. At the same time, the catalyst in the corresponding catalyst dispensing tank is observed through a sight glass to see if the catalyst is full.

[0029] After the catalyst dispensing tank is filled, close the corresponding catalyst outlet in the first multi-channel switching valve group.

[0030] Optionally, in the method for dispensing the polyolefin catalyst provided by this invention, the specific steps for completely replacing the air in the dispensing device with nitrogen are not limited; conventional methods in the industry are acceptable. To ensure catalyst activity, the dispensing can be performed 3-20 times depending on the actual situation. For example, when the nitrogen pressure is 0.1-0.5 MPa and the pressure in the catalyst dispensing tank farthest from the nitrogen storage tank reaches 0.2 MPa, the pressure can be released to the discharge tank, and this operation can be repeated. Specifically, the water / oxygen content in the catalyst dispensing tank farthest from the nitrogen storage tank can be detected to determine whether the dispensing can be stopped. For example, when the water / oxygen content in the catalyst dispensing tank farthest from the nitrogen storage tank is below 1 ppm, the dispensing can be stopped, and the catalyst dispensing can proceed.

[0031] Optionally, in the method for dispensing the catalyst for polyolefins provided by the present invention, each catalyst dispensing tank may dispense the catalyst simultaneously, in batches, or sequentially.

[0032] Optionally, in the method for dispensing catalysts for polyolefins provided by the present invention, during the process of dispensing catalysts into each catalyst dispensing tank, a pneumatic vibrating hammer is used to vibrate the catalyst dispensing tank.

[0033] Optionally, in the method for dispensing the catalyst for polyolefins provided by the present invention, during the process of dispensing the catalyst in each of the catalyst dispensing tanks, the flow port in the second multi-channel switching valve group is opened.

[0034] Optionally, in the dispensing method for the catalyst for polyolefins provided by the present invention, the nitrogen gas is refined nitrogen gas, and preferably the pressure of the nitrogen gas is 0.1-0.5 MPa.

[0035] Compared with the prior art, the present invention has the following advantages:

[0036] Beneficial Effect 1: The catalyst dispensing device for polyolefins provided by this invention, through the coordination of each passage in the first and second multi-channel switching valve groups with the catalyst product tank and each catalyst dispensing tank, combined with observation through a sight glass, can avoid overflow and achieve continuous and stable catalyst feeding. It is suitable for both solid and liquid catalysts. Simultaneously, through the coordination of the first and second multi-channel switching valve groups, the catalyst product tank, and two or more catalyst dispensing tanks, it can effectively prevent catalyst contact with air during catalyst transport. This fundamentally eliminates the risk of active components in the catalyst, such as titanium-containing compounds, reacting with air to generate titanium dioxide and hydrogen chloride, leading to reduced catalyst activity and environmental pollution from hydrochloric acid fumes, which pose significant harm to operators. Using this catalyst dispensing device, the precisely metered catalyst added to the polymerization reactor results in a stable reaction, preventing clumping inside the reactor and blockage of the catalyst feed line. This improves the accuracy of catalyst dispensing and can be used simultaneously for catalyst dispensing and storage (simply close the valves on the catalyst dispensing tank during storage). This fundamentally solves problems such as incomplete feeding of dry powder catalysts, resulting in catalyst waste, or high frequency of preparation and high labor intensity for operators when the equipment load is high.

[0037] Beneficial Effect 2: This dispensing device is a continuous, stable, and precise metering polyolefin dispensing device, particularly suitable for pilot-scale or small-scale plants requiring quantitative application studies of the same or different types of catalysts. It covers various solid catalysts such as linear low-density polyethylene, medium-density polyethylene, and high-density polyethylene, and is especially suitable for small-batch dispensing of catalyst from the catalyst storage tank. In experiments involving polyolefin catalyst research and evaluation, polymerization reaction engineering research, and the development of new polyolefin products, where catalysts are expensive and require experimental research on catalyst types, differential catalyst feed, and polymerization reaction conditions, small-batch dispensing of catalyst from the catalyst storage tank or flexible switching of catalyst feed is necessary. This ensures precise catalyst feeding during experiments, guarantees the accuracy of polymerization test parameters, and avoids catalyst waste and post-processing procedures.

[0038] Beneficial Effect 3: The catalyst dispensing device for polyolefins provided by this invention can match optimized test parameters according to polymerization tests under different conditions during performance evaluation of the developed catalyst. This enables the use of catalysts in multiple olefin polymerization reactors, allowing seamless switching of feed between multiple catalyst dispensing tanks, ensuring the accuracy of the target catalyst feed rate, and improving catalyst utilization efficiency. This solves the existing needs for multiple small-scale or pilot-scale polyolefin polymerization production units simultaneously conducting catalyst research and evaluation, polymerization process research, and new product development. By quantitatively filling each catalyst dispensing tank for use under different polymerization process conditions, the device avoids excessive catalyst waste and subsequent catalyst treatment while meeting the required catalyst feed rate for testing, ensuring safety and environmental protection. Furthermore, it effectively solves the problem of catalyst deactivation caused by modifications to the catalyst storage tank, polymerization reactor, or process pipeline of a polyolefin polymerization unit, or by catalyst deactivation due to human intervention, preventing normal catalyst feeding. The continuous and stable switching between multiple catalyst dispensing tanks in this invention ensures the continuous operation of the entire polyolefin unit.

[0039] Beneficial Effect 4: The catalyst dispensing device for polyolefins provided by this invention is particularly suitable for the dispensing and feeding system of dry powder catalysts in pilot or small-scale polyolefin test plants. Because solid dry powder catalyst feeding systems suffer from problems such as easy forced feeding, easy clogging of the catalyst injection pipe, and catalyst bridging within the feeder, this invention, by adding a pneumatic vibrating hammer to the catalyst dispensing tank and combining it with the adjustment of nitrogen supply and valve opening, can ensure the continuity and stability of the distribution and addition of solid dry powder catalysts, achieving stable control of the reaction system. Under quantitative and continuous stable feeding of solid dry powder catalysts, large fluctuations in reaction temperature, reaction pressure, yield, etc., can be avoided, enabling the polymerization plant to produce safely and stably.

[0040] Beneficial Effect 5: The polyolefin catalyst dispensing method provided by this invention, by employing a polyolefin catalyst dispensing device, can meet the needs of catalyst research and evaluation, polymerization process research, and new product development for companies with multiple polyolefin pilot or small-scale polymerization production units. At the discharge port at the bottom of the catalyst product tank, quantitative dispensing of the catalyst is achieved through a flexible connection with a multi-channel switching valve assembly. Through a second multi-channel switching valve assembly and the vent on the catalyst dispensing tank, refined nitrogen purging and safe pressure relief are achieved throughout the process. Combined with a sight glass on the catalyst dispensing tank for observing catalyst flow, and accessories such as the catalyst inlet, vent, pressure gauge, nitrogen inlet, and valves on the top of the catalyst dispensing tank, this method is effective. During the dispensing process, the catalyst dispensing tank is first purged with nitrogen before being fed through pipelines. Once the tank pressure and mass reach the set values, the relevant valves are closed. This process, which involves closing all valves before and after dispensing, prevents overflow and reduces product loss. Furthermore, if the polyolefin production unit does not require the addition of catalyst temporarily, the dispensed catalyst can be stored directly in the dispensing tank without affecting its activity. Attached Figure Description

[0041] Figure 1 This is a schematic diagram of a dispensing device for a catalyst for polyolefins provided by the present invention. Attached image description:

[0043] 1. Catalyst finished product tank; 2, 3, 4. Catalyst dispensing tanks; A, B. Sight glasses; C. Pneumatic vibratory hammer; VB-1. Nitrogen ball valve; VB-2, VB-3. Vault ball valves; VB-4. Nitrogen pipeline main ball valve; VB-5. Second four-way valve; VB-6. First four-way valve; VB-7, VB-8, VB-9. Second control valves. Detailed Implementation

[0044] The present invention will now be described in detail through embodiments. It should be noted that the following embodiments are only for further illustration of the present invention and should not be construed as limiting the scope of protection of the present invention. Those skilled in the art can make some non-essential improvements and adjustments to the present invention based on the above description.

[0045] In the description of this invention, it should be noted that the terms "top," "bottom," etc., indicating orientation or positional relationships are based on the orientation or positional relationships shown in the accompanying drawings and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," "third," and "fourth" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0046] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connection" and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0047] Furthermore, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0048] To address the problems of overflowing tanks, inaccurate quantitative distribution of catalysts, and unsuitability for catalyst packaging in existing polyolefin catalyst dispensing devices, this invention provides a dispensing device for olefin polymerization catalysts, comprising a catalyst product tank and at least two catalyst dispensing tanks, wherein the catalyst product tank and each catalyst dispensing tank are connected by a dispensing system.

[0049] The distribution system includes a first multi-way switching valve group that controls the flow of catalyst material and a second multi-way switching valve group that controls pressure relief;

[0050] The catalyst dispensing tank is equipped with a catalyst inlet, an air vent, and at least one catalyst flow port at the top; the catalyst finished product tank is equipped with a nitrogen inlet, a catalyst feeding port, a pressure detection device, and a safety valve air vent at the top, and a discharge port at the bottom;

[0051] The first multi-path switching valve assembly includes a catalyst inlet and at least two catalyst outlets. The number of catalyst outlets is the same as the number of catalyst dispensing tanks. Each catalyst outlet is connected to the catalyst inlet on the corresponding catalyst dispensing tank via a pipeline. Furthermore, the catalyst flow ports on two adjacent catalyst dispensing tanks are connected via a pipeline with a sight glass.

[0052] The second multi-way switching valve assembly includes an inlet, an outlet, and at least one flow port; the inlet is connected to the discharge port at the bottom of the catalyst finished product tank via a pipeline; the outlet is connected to the catalyst inlet of the first multi-way switching valve assembly via a pipeline; the number of flow ports is no more than the number of catalyst dispensing tanks, and each flow port is connected to the vent port on the corresponding catalyst dispensing tank via a pipeline.

[0053] The catalyst dispensing device for polyolefins provided by this invention is particularly suitable for distributing finished catalyst material from a catalyst tank for olefin polymerization into multiple dispensing tanks for catalyst polymerization evaluation and polymerization process research. This dispensing device utilizes a finished catalyst tank, multiple catalyst dispensing tanks of the same or different volumes, and a distribution system consisting of a multi-channel switching valve assembly, pipelines, sight glasses, and various control valves between them. By adjusting nitrogen pressure and valve openings, and with the aid of sight glasses and other accessories, it achieves quantitative filling of the catalyst in each dispensing tank. Furthermore, it prevents overflow and safety hazards caused by high pressure within the catalyst dispensing tanks. The dispensed catalyst storage tanks can meet the requirements of different polymerization process conditions, as well as the requirements for comparative studies of different types of catalysts or differential feed of the same catalyst for polymerization reaction conditions. This catalyst dispensing device can accurately and quantitatively dispense catalyst from the finished catalyst storage tank and flexibly switch the catalyst feed according to parameter adjustments during the polymerization experiment, achieving precise catalyst feeding during the experiment. It is particularly suitable for small-scale or pilot-scale polyolefin polymerization plants for catalyst performance evaluation and polymerization process research. In addition, the device can achieve precise quantitative dispensing of catalysts, and the bottom outlet of each catalyst dispensing tank can be connected to an olefin polymerization reactor or a catalyst packaging device. In this way, the catalyst in the dispensing catalyst storage tank can be directly put into the olefin polymerization reactor for catalytic polymerization, or it can be quantitatively packaged and then sold.

[0054] In one alternative implementation, the first and second multi-way switching valve assemblies are electrically connected to their respective controllers or manually controlled according to the catalyst feed rate. A typical example of an electrically connected controller is a DCS control system that transmits electrical signals to field solenoid valves, which in turn control compressed air to actuate the multi-way switching ball valves.

[0055] In one optional embodiment, the capacity of the catalyst finished product tank and the catalyst dispensing tank is not limited and can be adjusted according to the actual situation. Moreover, the capacity of each catalyst dispensing tank can be the same or different. For example, a catalyst finished product tank with a volume of 10-100L and a catalyst dispensing tank with a volume of 1-10L can be selected.

[0056] In one optional embodiment, each catalyst dispensing tank is equipped with a pneumatic vibrating hammer. During the dispensing process, the pneumatic vibrating hammer is activated appropriately, especially when dispensing solid dry powder catalysts, to avoid the inaccurate quantitative dispensing of catalysts due to pipeline blockage, bridging, or other reasons.

[0057] In one optional embodiment, a flow control valve is installed on the pipeline between each sight glass and the catalyst flow port on the corresponding catalyst dispensing tank. In a preferred embodiment, the flow control valve is located at the catalyst flow port on the catalyst dispensing tank, and the number of catalyst flow ports on the catalyst dispensing tank is the same as the number of flow control valves, the specific number is not limited, such as 1 or 2. During the catalyst dispensing process, the sight glass is used to observe whether the corresponding catalyst dispensing tank is full. When it is full, the corresponding catalyst outlet in the first multi-way switching valve group is closed in time, and the excess catalyst in the pipeline is circulated to other unfilled dispensing tanks through the flow control valve. Then, the corresponding flow control valve on the filled dispensing tank is closed. This can avoid the safety hazard of pressure difference caused by the closure of the corresponding catalyst outlet in the first multi-way switching valve group, and can also prevent catalyst waste caused by overflowing. By further setting the flow control valve at the catalyst flow port on the catalyst dispensing tank, the accuracy of catalyst dispensing can be further improved.

[0058] In one optional embodiment, the number of passages in the first and second multi-way switching valve groups is not specifically limited and can be determined based on the actual number of catalyst dispensing tanks to be filled. Assuming the total number of catalyst dispensing tanks is *a*, the total number of passages in the first multi-way switching valve group is *b*, where *b* = *a* + 1, and *a* is a natural number. For example, when there are two, three, four, or five catalyst dispensing tanks, the corresponding first and second multi-way switching valve groups are selected from three-way valves, four-way valves, five-way valves, or six-way valves. Specifically, the first multi-way switching valve group may be selected from a four-way valve containing one catalyst inlet and three catalyst outlets; the second multi-way switching valve group may be selected from a four-way valve containing one inlet, one outlet, and two flow ports.

[0059] In one optional embodiment, a second control valve is provided on the pipeline between each catalyst outlet in the first multi-channel switching valve group and the catalyst inlet on the corresponding catalyst dispensing tank. In a preferred embodiment, the second control valve is located at the catalyst inlet on the catalyst dispensing tank.

[0060] In one optional embodiment, a first control valve is provided on the pipeline between the inlet of the second multi-channel switching valve assembly and the discharge port at the bottom of the catalyst finished product tank. In a preferred embodiment, the first control valve is located at the discharge port at the bottom of the catalyst finished product tank.

[0061] In one optional embodiment, a pressure detection device is installed on the catalyst dispensing tank furthest from the nitrogen storage tank. In a preferred embodiment, each catalyst dispensing tank is equipped with a pressure detection device, such as a pressure monitor. In another optional embodiment, the dispensing device for the polyolefin catalyst also includes a discharge tank; the vent ports on each catalyst dispensing tank are connected to the discharge tank via pipelines containing vent valves. In a preferred embodiment, the vent valves are located at the vent ports on the catalyst dispensing tanks. By installing pressure detection devices on the catalyst dispensing tanks, combined with the control of the valves in the distribution system, when the pressure inside the dispensing tank is too high, the pressure can be released to the discharge tank through the vent ports on the catalyst dispensing tanks, ensuring the safe and stable operation of the device while guaranteeing the accuracy of the catalyst dispensing quantity in each dispensing tank.

[0062] In one optional embodiment, a nitrogen inlet is provided on the catalyst dispensing tank closest to the nitrogen storage tank; in a preferred embodiment, each catalyst dispensing tank is provided with a nitrogen inlet for introducing nitrogen into each catalyst dispensing tank to replace the air in the device and prevent the catalyst from becoming ineffective during the dispensing process.

[0063] In one optional implementation, the amount of catalyst in each catalyst dispensing tank can be measured by the capacity of the catalyst dispensing tank; alternatively, it can be obtained by weighing the catalyst using a scale installed at the bottom of the catalyst dispensing tank after closing all valves on the catalyst dispensing tank and completely disconnecting it from other pipelines and devices. However, the weighing method is relatively complicated and time-consuming, while measuring by the capacity of the catalyst dispensing tank is more convenient and faster.

[0064] In one alternative embodiment, the catalyst product tank is equipped with a stirring device, such as a stirrer.

[0065] In one optional embodiment, the pipelines involved in the dispensing device for the polyolefin catalyst are made of transparent PVC or polyurethane flexible tubing. The specific length and diameter of each pipeline are determined by the distance between the devices and the amount of catalyst being transported. In a preferred embodiment, tubing with a diameter of 1 / 8 to 1 / 2 inch is selected. By using transparent tubing, the transfer rate of the catalyst in each pipeline during the dispensing process can be directly observed, and then controlled and adjusted through valves.

[0066] The catalyst dispensing device for olefin polymerization provided by this invention is suitable for dispensing catalysts in various forms, such as solid dry powder and liquid. The catalyst in the finished product tank can be selected from any of the following: titanium-based catalysts, chromium-based catalysts, metallocene catalysts, or non-metallocene catalysts used in olefin polymerization. This catalyst dispensing device is particularly suitable for distributing dry powder catalyst materials for olefin polymerization to multiple polymerization units, meeting the needs of catalyst storage, feed distribution, and catalyst feeding for multiple polyolefin polymerization units, thereby improving catalyst utilization efficiency. Using this device for catalyst dispensing results in a simple process flow, enabling performance evaluation of different types of olefin polymerization catalysts, online switching of catalyst feed rates, and high operational flexibility. It has guiding significance for catalyst evaluation systems in polyolefin pilot and small-scale experimental units.

[0067] To better illustrate the present invention, Example 1 provides a specific catalyst dispensing device, but this device does not constitute a limitation on the embodiments of the present invention.

[0068] Example 1

[0069] This embodiment provides a specific dispensing device for a catalyst used in polyolefins, such as... Figure 1 As shown, it includes a catalyst product tank 1 connected by a distribution system and three catalyst dispensing tanks, namely catalyst dispensing tank 2, catalyst dispensing tank 3 and catalyst dispensing tank 4.

[0070] The catalyst finished product tank 1 is equipped with an agitator inside, and has a nitrogen inlet, a catalyst feeding port, and a safety valve vent at the top. The catalyst finished product tank 1 is equipped with a discharge port at the bottom.

[0071] Each of the three catalyst dispensing tanks is equipped with a catalyst inlet and a pressure gauge at the top (not shown in catalyst dispensing tanks 2 and 3), and an outlet at the bottom; each is equipped with a start-up vibrating hammer C on the side wall (not shown in catalyst dispensing tanks 2 and 3).

[0072] The catalyst dispensing tank 2 has two catalyst flow ports on its top, and the catalyst dispensing tanks 3 and 4 each have one catalyst flow port on their tops. The catalyst flow port on the top of catalyst dispensing tank 3 is connected to the first catalyst flow port on the top of catalyst dispensing tank 2 via a transparent pipeline sequentially equipped with a first flow control valve, a sight glass A, and a second flow control valve. The first and second flow control valves are located at the catalyst flow ports of catalyst dispensing tank 3 and 2, respectively. The second catalyst flow port on the top of catalyst dispensing tank 2 is connected to the catalyst flow port on the top of catalyst dispensing tank 4 via a transparent pipeline sequentially equipped with a third flow control valve, a sight glass B, and a fourth flow control valve. The third and fourth flow control valves are located at the second catalyst flow port of catalyst dispensing tank 2 and 4, respectively.

[0073] The distribution system includes a first four-way valve VB-6 controlling the flow of catalyst material and a second four-way valve VB-5 controlling pressure relief. These two four-way valves are electrically connected to their respective controllers (not shown) in the DCS control system. The first four-way valve VB-6 has one catalyst inlet and three catalyst outlets; the second four-way valve VB-5 has one inlet, one outlet, and two flow ports. The first four-way valve VB-6 and the second four-way valve VB-5 are remotely controlled via the DCS control system or manually controlled according to the catalyst feed rate.

[0074] The discharge port at the bottom of catalyst product tank 1 is connected to the inlet of the second four-way valve VB-5 via a transparent pipeline equipped with a first control ball valve, and the first control ball valve is located at the discharge port; the outlet of the second four-way valve VB-5 is connected to the catalyst inlet of the first four-way valve VB-6 via a transparent pipeline, and the three catalyst outlets of the first four-way valve VB-6 are respectively connected to the catalyst inlets at the top of the three catalyst dispensing tanks via pipelines equipped with second control valves (VB-8, VB-7 and VB-9). Among them, the second control valve VB-8 is located at the catalyst inlet of catalyst dispensing tank 2, the second control valve VB-7 is located at the catalyst inlet of catalyst dispensing tank 3, and the second control valve VB-9 is located at the catalyst inlet of catalyst dispensing tank 4.

[0075] Catalyst dispensing tank 3 has a vent at its top. This vent is connected to one port of the second four-way valve VB-5 via a pipeline containing a vent ball valve VB-3, and the vent ball valve VB-3 is located at the vent at the top of catalyst dispensing tank 3. Catalyst dispensing tank 4 has a vent at its top. This vent is connected to the other port of the second four-way valve VB-5 via a pipeline containing a vent ball valve VB-2, and the vent ball valve VB-2 is located at the vent at the top of catalyst dispensing tank 4.

[0076] The refined nitrogen inlet is connected to the nitrogen inlet on the catalyst finished product tank 1 and the nitrogen inlet at the top of the catalyst dispensing tank 3 via a pipeline equipped with a nitrogen pipeline main ball valve VB-4. A nitrogen balloon valve VB-1 is installed on the pipeline between the nitrogen pipeline main ball valve VB-4 and the nitrogen inlet at the top of the catalyst dispensing tank 3, and the nitrogen balloon valve VB-1 is located at the nitrogen inlet of the catalyst dispensing tank 3.

[0077] The nitrogen pipeline main ball valve VB-4, nitrogen ball valve VB-1, vent ball valve VB-2, and the vent port at the top of catalyst dispensing tank 1 are connected to the discharge tank and kerosene sealing tank via pipelines, respectively, and the discharge tank and kerosene sealing tank are connected in parallel.

[0078] The dispensing method provided by this invention is applicable to any type of polyolefin catalyst, but for convenience, the following dispensing will be carried out using a titanium-based catalyst system with magnesium alkoxy as the support.

[0079] Example 2

[0080] This embodiment provides a method for dispensing a catalyst for polyolefins, using the method described in Example 1. Figure 1 The illustrated catalyst filling device for polyolefins consists of three catalyst filling tanks filled sequentially (filling tank 2, filling tank 3, and filling tank 4). All pipelines used are 1 / 2-inch PVC pipes. The catalyst finished product storage tank has a capacity of 100L, catalyst filling tank 2 has a capacity of 10L, catalyst filling tank 3 has a capacity of 10L, and catalyst filling tank 4 has a capacity of 10L. The specific steps include the following:

[0081] (1) Nitrogen purging: Keep the catalyst finished product tank 1 and the distribution system in an interrupted state, and then open the main ball valve VB-4, nitrogen ball valve VB-1, vent ball valves VB-2 and VB-3, second four-way valve VB-5, first four-way valve VB-6, three second control valves VB-7, VB-8 and VB-9, first flow control valve, second flow control valve, third flow control valve and fourth flow control valve, etc.; purge the pipelines (including sight glass A and sight glass B) in the three catalyst dispensing tanks and the distribution system with nitrogen, control the pressure of the input refined nitrogen to 0.45MPa, and observe the pressure gauge indication of catalyst dispensing tank 4. When the pressure in catalyst dispensing tank 4 reaches 0.1MPa, depressurize and vent to the discharge tank. Repeat the operation 5 times, and analyze the gas composition in catalyst dispensing tank 4. If the water / oxygen content is below 1-5ppm, stop purging nitrogen.

[0082] (2) Catalyst dispensing tank 2: Close the two flow ports in VB-5, the two catalyst outlets in VB-6 that are connected to catalyst dispensing tank 3 and catalyst dispensing tank 4 respectively, VB-3, VB-7, VB-9, VB-2, the first flow control valve, the second flow control valve, the third flow control valve and the fourth flow control valve; Under the condition of maintaining the supply of refined nitrogen, at room temperature, under the stirring of the motor in the catalyst finished product tank 1, the pressure in the catalyst finished product tank 1 is increased by supplying nitrogen to make the tank pressure in the catalyst finished product tank 1 0.45MPa, and then open the first control ball valve at the bottom of the catalyst finished product tank 1, and feed the catalyst dispensing tank 2 through the transparent hose. If the catalyst in the transparent hose slows down during the feeding process, open the first flow control valve and the second flow control valve. At this time, a part of the pressurized catalyst will be transferred from the catalyst dispensing tank 2 to the catalyst dispensing tank 3. The capacity of the catalyst in the sight glass A can be observed to determine whether the dispensing tank 2 is full, so as to ensure the accuracy of the amount of catalyst. At the same time, the pneumatic vibrating hammer C on the catalyst dispensing tank 2 is activated appropriately during the filling process, which helps to quantitatively dispense the catalyst.

[0083] (3) Catalyst filling tank 3: After catalyst filling tank 2 is filled, close the catalyst outlet corresponding to catalyst filling tank 2 in VB-6, VB-8 and the second flow control valve, and open the catalyst outlet corresponding to catalyst filling tank 3 in VB-6 and VB-7 to feed the catalyst into catalyst filling tank 3. In order to maintain smooth catalyst feeding, open the two flow ports in VB-3, VB-2 and VB-5 to transfer a part of the pressurized catalyst from catalyst filling tank 3 to catalyst filling tank 4. When the pressure gauge of catalyst filling tank 4 indicates that the pressure is too high (more than 0.1MPa), open the ball valve of the kerosene sealing tank to release the pressure. During the filling process, start the pneumatic vibrating hammer C on catalyst filling tank 3 as appropriate.

[0084] (4) Catalyst Dispensing Tank 4: After observing through sight glass A that catalyst dispensing tank 3 is full, close the first flow control valve and the catalyst outlets corresponding to catalyst dispensing tank 3 in VB-7, VB-1, VB-3, and VB-6. Open the catalyst outlets corresponding to catalyst dispensing tank 4 in VB-9 and VB-6 and the fourth flow control valve to feed catalyst into catalyst dispensing tank 4. Determine whether catalyst dispensing tank 4 is full by observing the catalyst volume in sight glass B. During the dispensing process, appropriately activate the pneumatic vibrating hammer C on catalyst dispensing tank 4. After catalyst dispensing tank 4 is full, close the first control ball valve, VB-9, the fourth flow control valve, and VB-2 at the bottom of catalyst finished product tank 1. Weighing with a weighing scale, the weight of catalyst in each catalyst dispensing tank is basically the same.

[0085] Example 3

[0086] This embodiment provides a method for dispensing a catalyst for polyolefins, using the method described in Example 1.Figure 1 The diagram shows a dispensing device for polyolefin catalysts. It involves batch dispensing (dispensing tanks 2-3 and 4), with all pipelines using 1 / 2-inch PVC pipes. The catalyst finished product storage tank has a capacity of 50L, dispensing tank 2 has a capacity of 5L, dispensing tank 3 has a capacity of 5L, and dispensing tank 4 has a capacity of 5L. The specific steps include:

[0087] (1) Nitrogen purging: Keep the catalyst finished product tank 1 and the distribution system in an interrupted state, and then open the main ball valve VB-4, nitrogen ball valve VB-1, vent ball valves VB-2 and VB-3, second four-way valve VB-5, first four-way valve VB-6, three second control valves VB-7, VB-8 and VB-9, first flow control valve, second flow control valve, third flow control valve and fourth flow control valve, etc.; purge the pipelines (including sight glass A and sight glass B) in the three catalyst dispensing tanks and the distribution system with nitrogen, control the pressure of the input refined nitrogen to 0.45MPa, and observe the pressure gauge indication of catalyst dispensing tank 4. When the pressure in catalyst dispensing tank 4 reaches 0.1MPa, depressurize and vent to the discharge tank. Repeat the operation 5 times, and analyze the gas composition in catalyst dispensing tank 4. If the water / oxygen content is below 1-5ppm, stop purging nitrogen.

[0088] (2) Filling: Close the two flow ports in VB-5, the two catalyst outlets in VB-6 that are connected to catalyst dispensing tanks 3 and 4 respectively, VB-3, VB-7, VB-9, VB-2, the first flow control valve, the second flow control valve, the third flow control valve, and the fourth flow control valve; with purified nitrogen being continuously supplied, at room temperature, under the stirring of a motor in the catalyst finished product tank 1, pressurize the tank pressure in the catalyst finished product tank 1 by supplying nitrogen to 0.45MPa, then open the first control ball valve at the bottom of the catalyst finished product tank 1, and feed the catalyst dispensing tank 2 through a transparent hose. If the catalyst flow in the transparent hose slows down during the feeding process, open the first flow control valve, the second flow control valve, and the third flow control valve. The flow control valve and the fourth flow control valve allow a portion of the pressurized catalyst to be transferred from catalyst dispensing tank 2 to catalyst dispensing tanks 3 and 4, balancing the pressure in the three tanks (catalyst dispensing tank 2 acts as a buffer tank, while catalyst dispensing tanks 3 and 4 act as residual material storage tanks). The fullness of the three tanks can be determined by observing the catalyst volume in sight glasses A and B. Then, two flow ports in VB-3, VB-2, and VB-5 are opened, and the pressure gauge on catalyst dispensing tank 4 is consulted to prevent overflow or overpressure. If the pressure in catalyst dispensing tank 4 becomes too high (exceeding 0.1 MPa), the ball valve of the kerosene sealing tank is opened to release pressure until catalyst dispensing tanks 3 and 4 are full. During the distribution process, appropriately activating the pneumatic vibratory hammers C on each catalyst dispensing tank helps with the quantitative dispensing of the catalyst.

[0089] Example 4

[0090] This embodiment provides a method for dispensing a catalyst for polyolefins, using the method described in Example 1. Figure 1 The illustrated catalyst filling device for polyolefins consists of three catalyst filling tanks filled sequentially (filling tank 3-filling tank 2-filling tank 4). All pipelines used are 1 / 2-inch PVC pipes. The finished catalyst storage tank has a capacity of 10L, catalyst filling tank 2 has a capacity of 1L, catalyst filling tank 3 has a capacity of 1L, and catalyst filling tank 4 has a capacity of 1L. The specific steps include the following:

[0091] (1) Nitrogen purging: Keep the catalyst finished product tank 1 and the distribution system in an interrupted state, and then open the main ball valve VB-4, nitrogen ball valve VB-1, vent ball valves VB-2 and VB-3, second four-way valve VB-5, first four-way valve VB-6, three second control valves VB-7, VB-8 and VB-9, first flow control valve, second flow control valve, third flow control valve and fourth flow control valve, etc.; purge the pipelines (including sight glass A and sight glass B) in the three catalyst dispensing tanks and the distribution system with nitrogen, control the pressure of the input refined nitrogen to 0.45MPa, and observe the pressure gauge indication of catalyst dispensing tank 4. When the pressure in catalyst dispensing tank 4 reaches 0.1MPa, depressurize and vent to the discharge tank. Repeat the operation 5 times, and analyze the gas composition in catalyst dispensing tank 4. If the water / oxygen content is below 1-5ppm, stop purging nitrogen.

[0092] (2) Catalyst dispensing tank 3: Close the two flow ports in VB-5, the two catalyst outlets in VB-6 that are connected to catalyst dispensing tank 2 and catalyst dispensing tank 4 respectively, VB-3, VB-8, VB-9, VB-2, the first flow control valve, the second flow control valve, the third flow control valve and the fourth flow control valve; Under the condition of maintaining the supply of refined nitrogen, at room temperature, under the stirring of the motor in the catalyst finished product tank 1, the pressure in the catalyst finished product tank 1 is increased by supplying nitrogen to make the tank pressure in the catalyst finished product tank 1 0.45MPa, and then open the first control ball valve at the bottom of the catalyst finished product tank 1, and feed the catalyst dispensing tank 3 through the transparent hose. If the catalyst in the transparent hose slows down during the feeding process, open the first flow control valve and the second flow control valve. At this time, a part of the pressurized catalyst will be transferred from the catalyst dispensing tank 3 to the catalyst dispensing tank 2. The capacity of the catalyst in the sight glass A can be observed to determine whether the dispensing tank 3 is full, so as to ensure the accuracy of the amount of catalyst. At the same time, the pneumatic vibrating hammer C on the catalyst dispensing tank 3 is activated appropriately during the filling process, which helps to quantitatively dispense the catalyst.

[0093] (3) Catalyst filling tank 2: After catalyst filling tank 3 is filled, close the catalyst outlet VB-7, the first flow control valve and the second flow control valve in VB-1, VB-3 and VB-6 corresponding to catalyst filling tank 3. Open the catalyst outlet in VB-6 corresponding to catalyst filling tank 2 and VB-8 to feed the catalyst into catalyst filling tank 2. In order to maintain smooth catalyst feeding, open the flow port connected to VB-2 in VB-2 and VB-5, the third flow control valve and the fourth flow control valve to transfer a part of the pressurized catalyst from catalyst filling tank 2 to catalyst filling tank 4. Observe whether catalyst filling tank 2 is filled through sight glass B. When the pressure gauge of catalyst filling tank 4 indicates that the pressure is too high (more than 0.1MPa), open the ball valve of kerosene sealing tank to release the pressure. During the filling process, start the pneumatic vibrating hammer C on catalyst filling tank 2 appropriately.

[0094] (4) Catalyst Dispensing Tank 4: After observing through sight glass B that catalyst dispensing tank 2 is full, close the catalyst outlets corresponding to catalyst dispensing tank 2 in the third flow control valve, VB-8, and VB-6. Open the catalyst outlets corresponding to catalyst dispensing tank 4 in VB-9 and VB-6 to feed catalyst into catalyst dispensing tank 4. Determine whether catalyst dispensing tank 4 is full by observing the catalyst volume in sight glass B. During the dispensing process, appropriately activate the pneumatic vibrating hammer C on catalyst dispensing tank 4. After catalyst dispensing tank 4 is full, close the first control ball valve, VB-9, the fourth flow control valve, and VB-2 at the bottom of catalyst finished product tank 1. Weighing with a weighing scale, the weight of catalyst in each catalyst dispensing tank is basically the same.

[0095] After the catalyst is packaged using the methods described in Examples 2, 3, and 4, each catalyst packaging tank can be connected to the corresponding olefin polymerization reactor or the catalyst packaging device, depending on actual needs. The olefin polymerization reaction can be carried out in the liquid phase or the gas phase. The liquid phase reactor can be a loop reactor or a stirred tank reactor, etc., while the gas phase reactor can be a horizontal stirred bed reactor, a vertical stirred bed reactor, or a fluidized bed reactor, etc. These liquid phase reactors and gas phase reactors can also be arbitrarily combined.

[0096] Of course, the present invention may have other various embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and modifications according to the present invention, but these corresponding changes and modifications should all fall within the protection scope of the claims of the present invention.

Claims

1. A dispensing device for a catalyst for polyolefins, characterized in that, It includes a catalyst product tank and at least two catalyst dispensing tanks, wherein the catalyst product tank and each of the catalyst dispensing tanks are connected by a distribution system; The distribution system includes a first multi-channel switching valve group that controls the flow direction of catalyst material and a second multi-channel switching valve group that controls pressure relief. Each catalyst dispensing tank is equipped with a catalyst inlet, an vent, and at least one catalyst flow port at the top; the catalyst finished product tank is equipped with a nitrogen inlet, a catalyst feeding port, and a safety valve vent at the top, and a discharge port at the bottom; The first multi-channel switching valve assembly includes a catalyst inlet and at least two catalyst outlets. The number of catalyst outlets is the same as the number of catalyst dispensing tanks. Each catalyst outlet is connected to the catalyst inlet of the corresponding catalyst dispensing tank via a pipeline. Furthermore, the catalyst flow ports of two adjacent catalyst dispensing tanks are connected via a pipeline with a sight glass. The second multi-channel switching valve assembly includes an inlet, an outlet, and at least one flow port; the inlet is connected via a pipeline to the discharge port at the bottom of the catalyst finished product tank; the outlet is connected via a pipeline to the catalyst inlet of the first multi-channel switching valve assembly; the number of flow ports is no more than the number of catalyst dispensing tanks, and each flow port is connected via a pipeline to the vent port on the corresponding catalyst dispensing tank.

2. The dispensing apparatus for the catalyst for polyolefins as described in claim 1, characterized in that, Each of the catalyst dispensing tanks is equipped with a pneumatic vibrating hammer.

3. The dispensing apparatus for the catalyst for polyolefins as described in claim 1, characterized in that, Each sight glass is equipped with a flow control valve on the pipeline between it and the catalyst flow port on the corresponding catalyst dispensing tank.

4. The dispensing apparatus for the catalyst for polyolefins as described in claim 1, characterized in that, The first multi-way switching valve assembly is a four-way valve containing one catalyst inlet and three catalyst outlets; the second multi-way switching valve assembly is a four-way valve containing one inlet, one outlet and two flow ports.

5. The dispensing apparatus for the catalyst for polyolefins as described in claim 1, characterized in that, A second control valve is provided on the pipeline between each catalyst outlet in the first multi-channel switching valve group and the catalyst inlet on the corresponding catalyst dispensing tank.

6. The dispensing apparatus for the catalyst for polyolefins as described in claim 1, characterized in that, A first control valve is installed on the pipeline between the inlet of the second multi-channel switching valve assembly and the outlet at the bottom of the catalyst finished product tank.

7. The dispensing apparatus for the catalyst for polyolefins as described in claim 1, characterized in that, Each of the catalyst dispensing tanks is equipped with a pressure detection device.

8. The dispensing apparatus for the catalyst for polyolefins as described in claim 1, characterized in that, The catalyst dispensing device for polyolefins also includes an exhaust tank, and the vent on each catalyst dispensing tank is connected to the exhaust tank via a pipeline containing an exhaust valve.

9. The dispensing apparatus for the catalyst for polyolefins as described in claim 1, characterized in that, Each of the catalyst dispensing tanks is equipped with a nitrogen inlet.

10. The dispensing apparatus for the catalyst for polyolefins as described in claim 1, characterized in that, The catalyst finished product tank is equipped with a stirring device.

11. The dispensing apparatus for the catalyst for polyolefins according to any one of claims 1-10, characterized in that, All of the pipelines are made of stainless steel.

12. The dispensing apparatus for the catalyst for polyolefins as described in claim 3, characterized in that, The flow control valve is located at the catalyst flow port on the catalyst dispensing tank.

13. The dispensing apparatus for the catalyst for polyolefins as described in claim 5, characterized in that, The second control valve is located at the catalyst inlet on the catalyst dispensing tank.

14. The dispensing apparatus for the catalyst for polyolefins as described in claim 6, characterized in that, The first control valve is located at the discharge port at the bottom of the catalyst finished product tank.

15. The dispensing apparatus for the catalyst for polyolefins as described in claim 8, characterized in that, The vent valve is located at the vent port on the catalyst dispensing tank.

16. The dispensing apparatus for the catalyst for polyolefins as described in claim 11, characterized in that, Each of the pipelines mentioned is a 1 / 8 to 1 / 2 inch pipeline.

17. A method for dispensing a catalyst for polyolefins, characterized in that, The catalyst for polyolefins is dispensed using the dispensing apparatus according to any one of claims 1-16.

18. The packaging method as described in claim 17, characterized in that, Includes the following steps: The air in the dispensing device for the catalyst of the polyolefin is completely replaced with nitrogen; The catalyst in the finished catalyst tank is sequentially fed into the corresponding catalyst dispensing tank through pipelines via the discharge port at the bottom of the finished catalyst tank, the inlet of the second multi-channel switching valve group and the outlet of the second multi-channel switching valve group, the catalyst inlet in the first multi-channel switching valve group and at least one catalyst outlet in the first multi-channel switching valve group. At the same time, the catalyst in the corresponding catalyst dispensing tank is observed through a sight glass to see if the catalyst is full. After the catalyst dispensing tank is filled, close the corresponding catalyst outlet in the first multi-channel switching valve group.

19. The packaging method as described in claim 18, characterized in that, The catalysts can be packaged simultaneously, in batches, or sequentially in the various packaging tanks.

20. The packaging method as described in claim 18, characterized in that, During the catalyst filling process in each of the catalyst filling tanks, a pneumatic vibratory hammer is used to vibrate the catalyst filling tank.

21. The packaging method as described in claim 18, characterized in that, During the process of dispensing catalyst into each of the catalyst dispensing tanks, the flow port in the second multi-channel switching valve group is opened.

22. The packaging method as described in claim 18, characterized in that, The nitrogen gas mentioned is refined nitrogen gas.

23. The packaging method as described in claim 22, characterized in that, The pressure of the nitrogen gas is 0.1-0.5 MPa.

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