CN111744413A - An integrated skid-mounted device for measuring and conveying fragile particle slurry and its application - Google Patents

Abstract

The invention relates to an integrated skid-mounted device for measuring and conveying fragile particle slurry and application thereof, wherein the device comprises a slurry tank, a 1# mixer, a 1# mixing reaction stop tank, a 2# mixer, a 2# mixing reaction stop tank and a program-controlled three-way valve, an inlet of the 1# mixer is connected with an a additive measuring tank, an inlet of the 2# mixer is connected with a b additive measuring tank, one end of an outlet of the three-way valve is connected with a closed buffer tank, the other end of the outlet of the three-way valve is connected with a subsequent reaction system, and the slurry tank is also connected with the program-controlled three-way valve through another pipeline. The device can stably and uniformly add the slurry catalyst into the reactor and protect the particle form in the slurry catalyst in the pretreatment and conveying processes.

Description

An integrated skid-mounted device for measuring and conveying fragile particle slurry and its application

technical field

The invention relates to a feeding device, in particular to an integrated skid-mounted device for measuring and conveying fragile particle slurry and its application.

Background technique

Gas-phase fluidized bed process is widely used in polyolefin production process because of its advantages of simple equipment and process flow, low energy consumption, and high controllability. In order to make the gas-phase fluidized bed unit run smoothly, improve the production capacity and product quality, the slurry polyolefin catalyst and slurry polyethylene catalyst feeding system came into being. In order to improve product quality and performance, it is sometimes necessary to pretreat the catalyst for one or more times before adding it to the reactor, for example, one or several additives are used to reduce the catalyst, such as using triethylaluminum, monochlorodicarbonate in sequence. The titanium-based catalyst is treated with ethyl aluminum.

Polyolefin catalyst is a special sensitive substance, and its main components are very sensitive to moisture, oxygen, impurities, etc. For example, once contacted with air, components in the catalyst react with water and oxygen in the air, resulting in loss of catalyst activity or even complete deactivation. Furthermore, the deactivation process releases heat.

Polyolefin catalysts are generally brittle particles with specific morphology and structure, and their morphological characteristics will affect the stability of the polyolefin production process and the performance of the product. After the catalyst particles are broken, the performance of the catalyst will decrease, for example, the activity will decrease, which will affect the bed weight of the reactor and cause the reactor to become unstable; Flakes and other undesirable phenomena, and ash will affect the quality of polyethylene products and increase the difficulty of subsequent processing of polyethylene. The slurry polyolefin catalyst is a slurry with a certain concentration prepared by mixing traditional dry powder polyolefin catalyst with a specific diluent in a specific ratio. After being prepared into a slurry, the diluent has a certain protective effect on the morphology and structure of the catalyst. But long-distance, unsteady transport can still cause damage to the catalyst structure. The crushing of catalyst particles in the slurry catalyst during transportation will not only cause the above adverse effects, but also cause changes in the solid content, viscosity, and uniformity of particle dispersion in the slurry, which will affect subsequent transportation, metering, and temperature control processes.

The polyolefin catalyst has high activity, and the polymerization process releases heat. If the catalyst is injected into the reactor too fast, the polymerization reaction will be unstable, and the local reaction temperature will be too high, which will affect the stability of the process control and the quality of the product. Although the preparation of the dry powder catalyst into a slurry catalyst largely solves the problem that the catalyst feeding is difficult to control, the viscosity of the diluent will change after the preparation of the slurry catalyst due to the certain viscosity of the diluent. If the catalyst particles are in the diluent during feeding Uneven distribution will still lead to unstable polymerization reaction, high local reaction temperature, affecting the stability of process control and product quality. In addition, when the slurry catalyst is injected into the system, if the solid-liquid distribution is uneven, the injection port will be blocked.

Therefore, how to stably and uniformly add the slurry catalyst into the reactor and protect the particle morphology of the slurry catalyst during pretreatment and transportation is a technical problem to be solved urgently in the art.

Patent CN201820539352.8 discloses a device for conveying solid materials. Before the feeder transports materials into the reaction kettle, a vacuuming mechanism is used to evacuate the air in the feeder and the reaction kettle, and an inert gas is introduced into the feeder. It can avoid the reaction between the material and the moisture in the air and other substances, which can solve the problem that the material will come into contact with moisture during the production process of fluroxypyr, which will reduce the activity of the material and cause damage. CN200480013183.5 discloses a method for controlling polymer powder in gas phase polymerization, which includes introducing a slurry catalyst into a gas phase reactor undergoing olefin polymerization, introducing a precatalyst into a slurry feed tank 10, and passing a pump on the 10 11 is used to transport the slurry to the reactor 40, and it is operated in the range of 10-60 °C, preferably 30-45 °C, but the patent does not take into account the different states of the slurry catalyst during pretreatment, transportation, and feeding, The optimum processing temperature varies. CN200510102423.5 discloses a slurry or liquid catalyst feeding system, the device includes a slurry or liquid catalyst tank, a transfer pump, at least one six-way valve and a quantitative pipe. The feeding of catalyst slurry or liquid in the quantitative tube can be realized through the six-way valve, but the patent does not deal with the situation that the catalyst needs to be pretreated during feeding.

Patent 200820060332.9 discloses a precise metering and feeding device for viscous slurry, which provides a device that can control the viscosity of the slurry and accurately quantify the catalyst. a mixer, a first additive (eg reducing agent) a reaction buffer tank, a premixer, a second additive (eg reducing agent) b reaction buffer tank, the apparatus further comprising the following heat tracing circuits: the premixer, the The first additive (such as reducing agent) a reaction buffer tank and the connecting pipeline between them are provided with a first heat tracing device that controls the heat tracing temperature at 45-50°C; and/or the premixer, the first heat tracing device Two additives (such as reducing agent) b reaction buffer tank and the connecting pipeline between them are provided with a second heat tracing device that controls the heat tracing temperature at 60-65°C. The feeding method and device of the utility model can control the viscosity of the slurry, so that the catalyst or other viscous slurry and other reaction materials can be accurately quantified. However, the feeding device disclosed in the patent does not involve the wiring of pipelines and devices, stirring paddles and other key factors that can affect the protection of particles in the slurry, and the patent does not consider the temperature adjustment of the device under different environments and working conditions. question.

SUMMARY OF THE INVENTION

One of the objectives of the present invention is to provide an integrated skid-mounted device for measuring and transporting fragile particle slurry, which can stably and uniformly add the slurry catalyst into the reactor, and protect the particle shape in the slurry catalyst during pretreatment and transportation. .

The second purpose of the present invention is to provide a specific application of the device, which is used to stably and uniformly add the slurry catalyst into the reactor, prevent clogging during injection, and protect the particle morphology in the slurry catalyst during pretreatment and transportation. .

The object of the present invention is achieved through the following technical solutions:

An integrated skid-mounted device for measuring and conveying brittle particle slurry, including a slurry tank, a 1# mixer, a 1# mixing reaction retention tank, a 2# mixer, a 2# mixing reaction retention tank and a program-controlled Three-way valve, the inlet of the 1# mixer is connected to the additive metering tank a, the inlet of the 2# mixer is connected to the additive metering tank b, one end of the outlet of the three-way valve is connected to the closed buffer tank, and the other end is connected to the subsequent reaction system, The slurry tank is also connected to a program-controlled three-way valve through another pipeline. The device integrates the equipment and connecting pipes on a skid seat and is arranged in a line shape, and is compactly arranged in the direction of gravity flow and process flow. The slurry tank is installed in the The first agitator, the first agitator is provided with a plurality of blades, and is at least divided into 2 layers, and the second agitator is installed in the 1# mixing reaction and retention tank and the 2# mixing reaction retention tank, so The second agitator adopts a multi-layer paddle agitator and is arranged in at least 3 layers. This design can ensure that the slurry at the bottom of the tank can be uniformly mixed, and can also prevent the generation of large vortices and keep the liquid level. Stable, reducing the shear force on the slurry is beneficial to protect the fragile particle morphology. The special stirrer set in the tank of the device ensures the stability of the liquid level in the tank, which is conducive to the measurement of pressure, temperature, etc., and is conducive to the measurement of slurry, and realizes stable and accurate control of various parameters.

Preferably, the rotational speed of the first agitator is 60-120 rpm, the gap between the blade edge and the tank wall is 5-50 mm, and the gap between the bottommost blade and the tank bottom is 30-90 mm.

Preferably, the slurry tank, the additive metering tank a and the additive metering tank b are all provided with a gas inlet and a material inlet.

Preferably, the 1# mixer, the 1# mixing reaction retention tank and the pipeline between them, as well as the pipeline between the 1# mixing reaction retention tank and the program-controlled three-way valve, are provided to control the heat tracing temperature at 35 -55°C first heat tracing device;

The 2# mixer, the 2# mixing reaction retention tank and the pipeline between them, and the pipeline between the 2# mixing reaction retention tank and the program-controlled three-way valve are provided with the heat tracing temperature controlled at 50-65 ℃ the second heat tracing device.

Preferably, the slurry tank is arranged on the uppermost layer, the control valve, display instrument, and metering pump are arranged on the lower layer, and liquid level detection devices are installed in the slurry tank, 1# mixing reaction retention tank, and 2# mixing reaction retention tank.

Preferably, the device is provided with a metering pump and a cascade-controlled mass flow meter in the pipeline, and the metering pump adopts a plunger pump, a centrifugal pump or a peristaltic pump.

Preferably, the slurry tank, the 1# mixing reaction retention tank, and the 2# mixing reaction retention tank are equipped with pressure detection and control adjustment devices to ensure system stability.

The device is used for the transportation of polyolefin slurry catalyst, the slurry viscosity in the slurry tank is 500-3000mpa·s, and the treatment temperature is 20-30℃. The specific steps are: successively pass nitrogen and white oil into the device to complete the water, oxygen and impurity removal of the system; inject the polyolefin slurry catalyst into the slurry tank, start the agitator and the heat tracing device, and pump the slurry catalyst from the slurry tank It is transported and added to the subsequent reaction system through a process-controlled three-way valve, and additives for treating the slurry catalyst can be added according to actual needs.

The polyolefin slurry catalyst is formed by mixing white oil and magnesium-titanium series dry powder catalyst,

The additive is trihexylaluminum solution and/or diethylaluminum monochloride solution, the triethylaluminum solution is pumped from the additive metering tank a to the 1# mixer, and the slurry catalyst and triethylaluminum solution are completed in the 1# mixer After mixing, it is pumped to the 1# mixing reaction retention tank; the diethylaluminum monochloride solution is pumped from the b additive metering tank to the 2# mixer, and the catalyst and the diethylaluminum monochloride solution are completed in the 2# mixer After mixing, it is transported to 2# mixing reaction retention tank by pump.

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

1. The present invention provides an integrated skid-mounted control device for slurry metering and transportation, which can protect the fragile particles in the slurry, maintain the original shape of the particles during the metering and transportation process, and avoid blockage during the slurry metering and transportation process. With the function of removing blockage, the device can mix and react the slurry with different additives in sequence, so that the slurry can meet the requirements of subsequent processes, and the process system is simple.

2. The skid-mounted device integrates all equipment and pipelines on a skid base, and the conveying pipeline is short, especially suitable for the metering, conveying and processing of slurries prepared with fragile particles. The device protects the fragile particles with high sensitivity to water and oxygen and high requirements for shape protection through gas protection, accurate metering, and temperature control systems, and can stably handle slurries with a certain viscosity.

3. A special stirring device is installed in the slurry tank of the device to make the solid-liquid phase distribution of the slurry catalyst uniform and prevent the solid particles in the slurry from settling. The device is equipped with a temperature regulating device, which can perform cooling and heat tracing of the device, and is suitable for different working conditions.

4. The slurry catalyst transported by the device can be added to the reactor stably and evenly, preventing blockage during injection, and protecting the particle shape during pretreatment and transportation. The device occupies a small area, is easy to move and install, and has low equipment maintenance costs. It can be stopped and operated according to site requirements.

Description of drawings

Fig. 1 is the overall structure schematic diagram of the device of the present invention;

Fig. 2 is the structural representation of the agitator in the slurry tank of the present invention;

In the picture: 1-Slurry tank, 2-a additive metering tank, 3-1# mixer, 4-1# mixing reaction retention tank, 5-b additive metering tank, 6-2# mixer, 7-2# mixing tank Reaction retention tank, 8-closed buffer tank, 9-subsequent reaction system, 10-programmed three-way valve, a gap between blade edge and tank wall, b gap between the bottommost blade and the tank bottom (center line).

Detailed ways

The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

Referring to Fig. 1, the present invention provides an integrated skid-mounted device for measuring and conveying fragile particle slurry. The device includes a slurry tank 1, a additive metering tank 2, 1# mixer 3, 1# mixing reaction retention tank 4, b Additive metering tank 5, 2# mixer 6, 2# mixing reaction retention tank 7, closed buffer tank 8, program-controlled three-way valve 10; the device also includes segmented heat tracing devices, such as: a additive metering tank, 1# mixing tank Heat tracing devices are installed between the reactor, the 1# mixing reaction retention tank and the pipeline between them, the pipeline between the 1# mixing reaction retention tank and the program-controlled three-way valve, and the program-controlled three-way valve and the subsequent system pipeline. b Additive metering tank, 2# mixer, 2# mixing reaction retention tank and the pipeline between them, as well as the pipeline between the 2# mixing reaction retention tank and the program-controlled three-way valve, and the program-controlled three-way valve and the subsequent system pipeline are all Install heat tracing. The heat tracing device is controlled by subsection program, and different temperature programs can be set according to requirements. The processing temperature between the 1# mixer, the 1# mixing reaction retention tank and the pipeline between them and the pipeline between the 1# mixing reaction retention tank and the program-controlled three-way valve can be set to 35-55℃, and the viscosity is 2500-3500mpa· s; The processing temperature between the 2# mixer, the 2# mixing reaction retention tank and the pipeline between them and the pipeline between the 2# mixing reaction retention tank and the program-controlled three-way valve can be set to 50-65 °C, and the viscosity is 3500- 4500mpa·s.

This device integrates all equipment and pipes on a skid base, and is designed with short conveying pipelines and linear arrangement of processes and equipment. The slurry is a plug flow in the conveying pipeline, reducing the velocity gradient of the fluid to protect the particle shape in the slurry from being damaged. All equipment, instruments, pipelines, etc. in the skid-mounted device are integrated on the skid base, and are arranged in a reasonable three-dimensional manner according to the material flow direction, so as to facilitate the fluid flow or transportation by gravity. For example, the slurry tank is arranged on the uppermost layer, and the slurry can flow to the lower pipeline or device by gravity. This method makes the process path the shortest, which can reduce the wear and energy loss of the particles in the passive transportation during the slurry transportation process, which is conducive to easy transportation. Protection of crushed particle form. The main control valves, display instruments, metering pumps, etc. are arranged in the lower layer, which is convenient for operators to operate, inspect and maintain on site.

The slurry tank, the a additive metering tank and the b additive metering tank of the device are provided with a gas inlet and a material inlet. Inert gas, such as nitrogen, can be introduced into the unit through the gas inlet on the tank. Materials, such as slurry catalyst, can be input into the device through the material inlet of the slurry tank; for example, additive a can be input into the device through the material inlet of the additive metering tank.

The device can choose to use additives according to production needs. For example, if a additive is selected, the catalyst slurry can be treated by using a 1# mixer and a 1# mixing reaction residence tank. When selecting additives a and b, 1# mixer, 1# mixing reaction retention tank, 2# mixer and 2# mixing reaction retention tank can be used to process the catalyst slurry at the same time.

The mixers such as the 1# mixer and the 2# mixer in this device are non-power mixers.

A stirring device is installed in the slurry tank of the device to make the solid-liquid phase distribution of the slurry catalyst uniform and prevent the solid particles in the slurry from settling. The agitator is equipped with multiple blades, which are arranged in at least 2 layers, and the distribution of 3-5 layers is better. This design can ensure that the slurry at the bottom of the tank can be uniformly mixed, and can also prevent the generation of large vortices and keep the liquid The stability of the surface and the reduction of the shear force on the slurry are beneficial to protect the fragile particle morphology. The special stirrer set in the tank of the device ensures the stability of the liquid level in the tank, which is conducive to the measurement of pressure, temperature, etc., and is conducive to the measurement of slurry, and realizes stable and accurate control of various parameters. The blades of the agitator should be smooth without damage, and the stirring speed should be slow. For example, set the rotating speed to 60-120 rpm. If the rotating speed is too high, the catalyst particles will be damaged. If the rotating speed is too low, the catalyst particles will settle. As shown in Figure 2, the gap between the blade edge and the tank wall is 5-50mm. The gap between the bottom blade and the tank bottom (center line) needs to be 30-90mm. This design allows the precipitated material to be quickly slurried again.

The 1# mixing reaction holding tank and the 2# mixing reaction holding tank of the device are equipped with stirring devices to mix the additives and the slurry catalyst evenly, and at the same time, make the mixed slurry catalyst solid and liquid phase distribution evenly, and prevent the solid particles in the slurry from settling. The special agitator set in the tank of the device ensures the stability of the liquid level in the tank, which is conducive to the measurement of pressure, temperature, liquid level, etc., and is conducive to the measurement of slurry, and realizes stable and accurate control of various parameters. Multilayer paddle agitators are preferred. The agitator is provided with a plurality of blades, which are arranged in at least 3 layers, preferably 3-6 layers. After the slurry enters the 1# mixing reaction retention tank and the 2# mixing reaction retention tank, the slurry is in a state of plug flow through the stirring of the stirring paddle, so as to ensure the consistency of the slurry residence time and prevent the slurry and additives from reacting for too long or reacting. insufficient. The blades of the agitator should be smooth without damage, and the speed should be slow during stirring.

The liquid level detection device is installed in the slurry tank, 1# mixed reaction retention tank and 2# mixed reaction retention tank of the device to monitor the liquid level in real time to ensure the stability and continuity of the feeding. Two types of liquid level gauges can be installed at the same time to ensure the accuracy of the data. Different pressure, magnetic float, ultrasonic and other forms can be selected.

The device can be selected between the slurry tank and the program-controlled three-way valve, between the slurry tank and the mixer, between the additive metering tank and the mixer, between the mixer and the reactor, and between the reactor and the program-controlled three-way valve. Use metering pumps, such as plunger pumps, centrifugal pumps, peristaltic pumps, etc. The delivery of the additive is preferably a piston pump. The best way to transport slurry is screw pump. The screw pump stator is made of corrosion-resistant materials with certain elasticity, such as special tetrafluoro rubber, to ensure that the slurry containing solid particles can be smoothly boosted and transported without being easily worn and broken.

Pressure detection and control and adjustment devices are installed in the slurry tank, 1# mixed reaction retention tank and 2# mixed reaction retention tank of the device to monitor system pressure in real time to ensure system stability.

The device is equipped with a flow meter in the slurry material, and the flow meter cascade control is designed to realize the precise control of the slurry and additives added. Such as slurry tank, a additive metering tank, 1# mixer, pipeline between 1# mixing reaction retention tank and pipeline between 1# mixing reaction retention tank and program-controlled three-way valve, and between program-controlled three-way valve and subsequent system Cascade-controlled mass flow meters are installed in the pipeline for accurate metering.

All pipelines and tanks of the device are equipped with electric heat tracing system, which can control the temperature of the system by automatic adjustment, improving the accuracy and convenience of temperature control; at the same time, manual mode is also set. A circulating water temperature adjustment system is installed in key pipelines and tanks, for example, a jacket is installed in the slurry tank 1, and the inside is circulating water, which can be cooled or heated. The electric heat tracing system and circulating water system of the device can ensure the stability of the internal temperature of the device under different environments and working conditions, prevent the catalyst particles from settling and cause uneven distribution of the catalyst in the slurry, prevent the slurry viscosity from increasing and block the pipeline, and prevent the catalyst from being overheated. Aging and performance are affected.

The device is equipped with a closed reaction retention tank.

The slurry tank, a additive metering tank, 1# mixed reaction retention tank, b additive metering tank, 2# mixed reaction retention tank, and sealed reaction retention tank are all equipped with venting devices such as venting valves.

The subsequent reaction system of the device can be an aggregate device of an ethylene polymerization device.

Example 1

Connect the purified nitrogen gas to the gas inlet of the slurry tank 1, start the pressure control device of the agitator, set the program-controlled three-way valve to the subsequent system device from the slurry tank 1, and open the closed buffer tank 8 when the gauge pressure rises by 200KPa. Close the vent valve of the buffer tank 8, and pressurize it after the pressure returns to zero. This was repeated 10 times to ensure that all the air in the system was replaced with nitrogen. Connect the purified nitrogen to the gas inlet of the 1# mixing reaction retention tank, start the agitator pressure control device, set the program-controlled three-way valve to the 1# mixing reaction retention tank to the subsequent system device, and wait for the closed buffer tank 8 The gauge pressure rises by 200KPa, and the vent valve of the closed buffer tank 8 is opened, and the pressure is charged after the pressure returns to zero. This was repeated 10 times to ensure that all the air in the system was replaced with nitrogen. Connect the purified nitrogen to the gas inlet of the 2# mixing reaction retention tank, start the agitator pressure control device, set the program-controlled three-way valve to the 2# mixing reaction retention tank to the subsequent system device, and wait for the closed buffer tank 8 The gauge pressure rises by 200KPa, and the vent valve of the closed buffer tank 8 is opened, and the pressure is charged after the pressure returns to zero. This was repeated 10 times to ensure that all the air in the system was replaced with nitrogen.

Connect the white oil to the material inlet of the slurry tank 1, start the agitator, pressure control and temperature control devices, add 100L of white oil, stir for 30min, set the program-controlled three-way valve to the slurry tank 1 to the subsequent system device, Open the vent valve of the closed buffer tank 8, and discharge the white oil into the closed buffer tank 8. Connect the white oil to the material inlet of the 1# mixing reaction retention tank, start the mixer, pressure control and temperature control devices, add 50L of white oil, stir for 30min, set the program-controlled three-way valve to the 1# mixing reaction retention tank Into the subsequent system device, open the vent valve of the closed buffer tank 8, and discharge the white oil into the closed buffer tank 8. Connect the white oil to the material inlet of the 2# mixing reaction retention tank, start the mixer, pressure control and temperature control devices, add 50L of white oil, stir for 30min, set the program-controlled three-way valve to the 2# mixing reaction retention tank Into the subsequent system device, open the vent valve of the closed buffer tank 8, and discharge the white oil into the closed buffer tank 8.

According to the above steps, the water, oxygen and impurity removal of the device can be completed, which can prevent the material from reacting with moisture and other substances in the air.

Example 2

According to Example 1, the steps of removing water, oxygen and impurities in the device were completed.

The catalyst was prepared with reference to WO2004101630A1: a total of 500L slurry catalyst was prepared by mixing 72wt% white oil and 28wt% magnesium-titanium series dry powder catalyst. Use this device to deliver this catalyst to subsequent systems.

The agitator in the slurry tank 1 is a multi-layer paddle type and fully mixed agitator, and the set rotation speed is 120 rpm. Start agitator and heat tracing device. Start its temperature control device, pressure control device, liquid level measurement device and other devices.

The program-controlled three-way valve is set as the slurry tank 1 to the subsequent system device, and the slurry catalyst is pumped from the slurry tank 1 and added to the subsequent system device through the process-controlled three-way valve.

Example 3

According to Example 1, the steps of removing water, oxygen and impurities in the device were completed.

The treatment catalyst was prepared with reference to WO2004101630A1: a total of 600L slurry catalyst was prepared by mixing 70wt% white oil and 30wt% magnesium-titanium series dry powder catalyst. The slurry catalyst is treated with triethylaluminum solution and then sent to the aggregate device of the ethylene polymerization device.

The agitator in the slurry tank 1 is a multi-layer paddle type and fully mixed agitator, and the set rotation speed is 120 rpm. Start agitator and heat tracing device.

Set the processing temperature between the 1# mixer, the 1# mixing reaction retention tank and the pipeline between them, and the pipeline between the 1# mixing reaction retention tank and the program-controlled three-way valve, and set the maximum control temperature not higher than 50°C; set the processing temperature between 2# mixer, 2# mixing reaction retention tank and the pipeline between them and the pipeline between 2# mixing reaction retention tank and the program-controlled three-way valve to 55°C, and set the maximum control temperature not higher than 65℃. The set temperature of the connection pipeline between the program-controlled three-way valve and the subsequent system is 65°C, and the set maximum control temperature is not higher than 70°C. The temperature setting is based on the curve of viscosity changing with temperature under a certain shear rate. Start agitator and heat tracing device.

Start other heat tracing devices, temperature control devices, pressure control devices, liquid level measurement devices and other devices.

Set the program-controlled three-way valve to the 1# mixing reaction retention tank to the aggregate device of the ethylene polymerization unit. The treated slurry catalyst is pumped from the 1# mixing reaction retention tank and fed to the ethylene polymerization unit through the process-controlled three-way valve.

Example 4

According to Example 1, the steps of removing water, oxygen and impurities in the device were completed.

The treatment catalyst was prepared with reference to WO2004101630A1: a total of 450L slurry catalyst was prepared by mixing 75wt% white oil and 25wt% magnesium-titanium series dry powder catalyst. The slurry catalyst is treated with trihexylaluminum solution and diethylaluminum monochloride solution and then sent to the aggregate device of the ethylene polymerization device.

The agitator in the slurry tank 1 is a multi-layer paddle type and fully mixed agitator, and the set rotation speed is 120 rpm. Start agitator and heat tracing device.

Set the processing temperature between the 1# mixer, the 1# mixing reaction retention tank and the pipeline between them, and the pipeline between the 1# mixing reaction retention tank and the program-controlled three-way valve, and set the maximum control temperature not higher than 50°C; set the processing temperature between 2# mixer, 2# mixing reaction retention tank and the pipeline between them and the pipeline between 2# mixing reaction retention tank and the program-controlled three-way valve to 55°C, and set the maximum control temperature not higher than 65℃. The set temperature of the connection pipeline between the program-controlled three-way valve and the subsequent system is 65°C, and the set maximum control temperature is not higher than 70°C. The temperature setting is based on the curve of viscosity changing with temperature under a certain shear rate. Start agitator and heat tracing device.

Start other heat tracing devices, temperature control devices, pressure control devices, liquid level measurement devices and other devices.

The slurry catalyst in the slurry tank 1 was preheated to 25°C, and transported to the 1# mixer with a screw pump, and the flow rate was measured by a mass flow meter installed on the pipeline. The triethylaluminum solution is pumped from the additive metering tank a to the 1# mixer, and the flow is measured by a mass flow meter installed on the pipeline. After the slurry catalyst and the triethylaluminum solution are mixed in the 1# mixer, they are pumped to the 1# mixing reaction retention tank.

The reduced slurry catalyst is pumped to the 2# mixer, and the flow is measured by a mass flow meter installed on the pipeline. The diethylaluminum monochloride solution is pumped from the b additive metering tank to the 2# mixer, and the flow is measured by a mass flow meter installed on the pipeline. After the catalyst and the diethylaluminum monochloride solution are mixed in the 2# mixer, they are pumped to the 2# mixing reaction retention tank.

The program-controlled three-way valve is set as the 2# mixing reaction retention tank to the aggregate device of the ethylene polymerization unit. The treated slurry catalyst is pumped from the 2# mixing reaction retention tank, and fed to the ethylene polymerization unit through the process-controlled three-way valve. .

The foregoing description of the embodiments is provided to facilitate understanding and use of the invention by those of ordinary skill in the art. It will be apparent to those skilled in the art that various modifications to these embodiments can be readily made, and the generic principles described herein can be applied to other embodiments without inventive step. Therefore, the present invention is not limited to the above-mentioned embodiments, and improvements and modifications made by those skilled in the art according to the disclosure of the present invention without departing from the scope of the present invention should all fall within the protection scope of the present invention.

Claims (10)

1. An integrated skid-mounted device for measuring and transporting fragile particle slurry, comprising a slurry tank (1), a 1# mixer (3), a 1# mixing reaction retention tank (4), a 2# mixing tank from upstream to downstream in sequence Mixer (6), 2# mixing reaction retention tank (7) and program-controlled three-way valve (10), the inlet of the 1# mixer (3) is connected to a additive metering tank (2), and the 2# mixer ( 6) The inlet is connected to the additive metering tank (5), one end of the outlet of the three-way valve is connected to the closed buffer tank (8), the other end is connected to the subsequent reaction system (9), and the slurry tank (1) is also connected through another pipe connected with the program-controlled three-way valve (10), characterized in that, The device integrates equipment and connecting pipes into a skid, and is compactly arranged in the direction of gravity flow and process flow. A first agitator is installed in the slurry tank (1), and the first agitator is provided with a plurality of blades , and at least divided into 2 layers of arrangement, the second agitator is installed in the 1# mixed reaction retention tank (4) and the 2# mixed reaction retention tank (7), and the second agitator adopts a multi-layer paddle type blender, and arrange in at least 3 layers. 2. The integrated skid-mounted device for measuring and conveying a kind of fragile particle slurry according to claim 1, wherein the rotating speed of the first agitator is 60-120 rpm, and the gap between the blade edge and the tank wall is 5 rpm. -50mm, the gap between the bottom blade and the bottom of the tank is 30-90mm. 3. The integrated skid-mounted device for measuring and conveying fragile particle slurry according to claim 1, wherein the slurry tank (1), the a-additive metering tank (2), the b-additive metering tank (5) ) are equipped with gas inlet and material inlet. 4. The integrated skid-mounted device for measuring and transporting fragile particle slurry according to claim 1, wherein, The 1# mixer (3), the 1# mixing reaction retention tank (4) and the pipeline between them, and the pipeline between the 1# mixing reaction retention tank (4) and the program-controlled three-way valve (10) Equipped with the first heat tracing device to control the heat tracing temperature at 35-55℃; The 2# mixer (6), the 2# mixed reaction retention tank (7) and the pipeline between them, and the pipeline between the 2# mixed reaction retention tank (7) and the program-controlled three-way valve (10) A second heat tracing device is provided to control the heat tracing temperature at 50-65°C. 5. The integrated skid-mounted device for measuring and transporting fragile particle slurry according to claim 1, wherein the slurry tank (1) is arranged on the uppermost layer, and the control valve, the display instrument and the metering pump are arranged in the uppermost layer. In the lower layer, a liquid level detection device is installed in the slurry tank (1), the 1# mixed reaction retention tank (4), and the 2# mixed reaction retention tank (7). 6. The integrated skid-mounted device for measuring and conveying fragile particle slurry according to claim 1, wherein the device is provided with a metering pump and a cascade-controlled mass flowmeter in the pipeline, and the metering pump is Use plunger, centrifugal or peristaltic pumps. 7. The integrated skid-mounted device for measuring and transporting fragile particle slurry according to claim 1, wherein the slurry tank (1), the 1# mixing reaction retention tank (4), the 2# mixing reaction A pressure detection and control adjustment device to ensure the stability of the system is installed in the stay tank (7). 8. The application of an integrated skid-mounted device for measuring and conveying fragile particle slurry according to claim 1, wherein the device is used for the transportation of polyolefin slurry catalyst, and the slurry tank (1) handles the slurry viscosity of 500-3000mpa·s, treatment temperature is 20-30℃. 9. The application of an integrated skid-mounted device for measuring and transporting fragile particle slurry according to claim 8, wherein the specific steps are: successively feeding nitrogen and white oil into the device to complete the dewatering, Deoxygenation and impurity removal; inject the polyolefin slurry catalyst into the slurry tank (1), start the agitator and the heat tracing device, the slurry catalyst is pumped from the slurry tank (1), and added to the subsequent process through the process control three-way valve (10). In the reaction system (9), additives for treating the slurry catalyst can be added according to actual needs. 10. The application of an integrated skid-mounted device for measuring and transporting fragile particle slurry according to claim 9, wherein the polyolefin slurry catalyst is formed by mixing white oil and magnesium-titanium series dry powder catalyst, The additive is trihexylaluminum solution and/or diethylaluminum monochloride solution, the triethylaluminum solution is pumped from the additive metering tank (2) to the 1# mixer (3), the slurry catalyst and the triethylaluminum solution After the 1# mixer (3) completes the mixing, it is transported to the 1# mixing reaction retention tank (4) by the pump; The diethylaluminum monochloride solution is pumped from the b additive metering tank (5) to the 2# mixer (6). After the catalyst and the diethylaluminum monochloride solution are mixed in the 2# mixer (6), the Transferred to the 2# mixing reaction retention tank (7).

Images