Kettle reactor with polymer online removal function and application

Abstract

The invention discloses a tank reactor with a polymer online removal function and application. The tank reactor comprises a reactor shell, a heat exchanger, a stirrer, an ultrasonic transducer and an ultrasonic generator, a stirring shaft of the stirrer is arranged at the position of a middle shaft in the reactor; a plurality of heat exchangers are arranged around the stirring shaft in the reactor; the ultrasonic transducer is arranged on the reactor shell and is positioned between the inner wall of the reactor and the heat exchanger; the ultrasonic generator is positioned outside the reactor and is electrically connected with the ultrasonic transducer. The ultrasonic transducers are installed on the periphery of the interior of the reactor wall, low-molecular polymers generated by reaction are prevented from being attached to the heat exchange tubes through the ultrasonic oscillation effect, and long-period stable operation of the polymerization reactor is achieved.

Description

Technical Field

[0001] The present invention relates to the field of producing low-carbon olefins by ethylene oligomerization, and in particular to a kettle reactor with a polymer online removal function and its application; more particularly to a reactor for producing 1-butene and / or 1-octene by ethylene oligomerization, and the reactor has a polymer online removal function. Background Art

[0002] 1-Butene and 1-octene are the main comonomers for producing linear low-density polyethylene (LLDPE) and high-density polyethylene (HDPE). As tie molecules, the short and side-branched structures they provide can give polyethylene lamellae a stronger bond between them, significantly improving the mechanical properties of polyethylene products such as tensile strength, impact strength, and tear resistance. In the industrial process, it is generally necessary to add 1% to 10% of comonomers to produce copolymerized polyethylene.

[0003] At present, the industrial production technology of 1-octene can be roughly divided into three categories. The first category is to obtain polymerization-grade 1-octene from mixed raw materials such as Fischer-Tropsch olefins through separation and purification; the advantages of this type of technology are low raw material and processing costs, and the disadvantages are high dependence on raw material resources, high impurity content of products and poor quality. The second category is the traditional ethylene polymerization technology for preparing α-olefins. This technology uses ethylene as raw material to produce a series of α-olefins, and then separates 1-butene, 1-hexene and 1-octene from the intermediate materials; the advantages of this type of process are wide application range and the ability to produce 1-butene, 1-hexene and 1-octene at the same time. The disadvantages are that the overall selectivity of 1-butene, 1-hexene and 1-octene is low and the output ratio of the two copolymer monomers cannot be flexibly adjusted, the single set of equipment has a large production capacity and high operating energy consumption. The third category is high-selective ethylene oligomerization technology, which refers to the tetramerization of ethylene into 1-octene, etc. The advantages of this type of technology are a wide range of applications and can be widely used as a polyethylene supporting device. It has the advantages of high selectivity, good product quality, and low construction and operation costs. This type of technology has one set of equipment corresponding to one monomer, and the product plan is clear. It is the most promising copolymer production technology in the future.

[0004] The catalyst for the tetramerization of ethylene to produce 1-octene is usually a multi-component catalytic system composed of transition metals, ligands, and alkyl aluminum alkanes. The industrial production process uses heat exchange tubes installed inside the reactor to remove heat. When the process device is in operation, a small amount of catalyst will usually adhere to the wall of the heat exchange tube inside the reactor, and a layer of low-molecular polyethylene will be generated over a long period of time, which will reduce the heat exchange effect of the heat exchanger, resulting in poor heat exchange performance of the reactor, and the inability to control the reaction temperature. The reactor is forced to be switched regularly to clean the reactor heat exchange tube, which is not only labor-intensive and costly, but also increases material consumption and affects the stability of the operating device. Therefore, in view of the huge demand for 1-octene in the current polyethylene plant, it is important to develop a new process technology that can prevent scale and remove oligomers, and realize the continuous and stable production of high-quality 1-octene copolymer monomer technology through ethylene polymerization. It has important economic and practical value and scientific research significance.

[0005] At present, the industrial production technology of 1-butene can be roughly divided into three categories. The first category is to obtain polymerization-grade 1-butene from mixed raw materials such as cracking C4 or Fischer-Tropsch olefins through separation and purification; the advantages of this type of technology are low raw material and processing costs, and the disadvantages are high dependence on raw material resources, high impurity content of products and poor quality. The second category is the traditional ethylene polymerization technology for preparing α-olefins. This technology uses ethylene as raw material to produce a series of α-olefins, and then separates 1-butene and 1-hexene from the intermediate materials; the advantages of this type of process are wide application range and the ability to produce 1-butene and 1-hexene at the same time. The disadvantages are that the overall selectivity of 1-butene and 1-hexene is low and the output ratio of the two copolymer monomers cannot be flexibly adjusted, the single set of equipment has a large production capacity, and the operating energy consumption is high. The third category is high-selective ethylene oligomerization technology, which refers to the synthesis of 1-butene from ethylene dimerization. The advantages of this technology are a wide range of applications and can be widely used as a polyethylene supporting device. It has the advantages of high selectivity, good product quality, and low construction and operation costs. This technology has one set of equipment corresponding to one monomer, and the product plan is clear. It is the most promising copolymer production technology in the future.

[0006] The catalyst for ethylene dimerization to produce 1-butene is usually a multi-catalyst system composed of a transition metal, a ligand and an alkyl aluminum, such as the three-way catalytic system disclosed in US2943125, which has the general formula of Ti(OR)4 or Ti(OR')4 alkoxytitanium or aryloxytitanium, an aluminum compound and a Lewis base additive, and the four-way catalytic system disclosed in CN 105899289 A, which has the general formula of Ti(OR)4 titanate, an ether modifier, an aluminoxane and the other aluminum compound. The process adopts the method of extracting the reaction liquid through a circulating pump, cooling it in a heat exchanger and returning it to the reactor, thereby achieving the purpose of removing the reaction heat. Since the catalyst will also adhere to the heat exchange tube wall in a small amount in this process, a layer of polyethylene will be generated over a long period of time to reduce the heat exchange effect of the heat exchanger. The heat exchanger needs to be disassembled and cleaned regularly. Under high pressure, it is necessary to withdraw the material, install a blind plate, and disassemble the heat exchanger head for high-pressure water gun cleaning. Not only is the operation intensity high and the cost high, but it also increases material consumption and affects the stability of the operating device. Therefore, it is also urgent to develop a process technology that can remove the oligomers stuck on the heat exchanger online, and to achieve ethylene polymerization to continuously and stably produce high-quality 1-butene copolymer monomer technology, which has important economic and practical value and scientific research significance.

[0007] As for the technology of anti-scaling and descaling of heat exchangers, the most widely used technology at present is the application of ultrasonic technology for scale prevention. Dalas E. and Nishida I. et al. found through experimental research in 2001 and 2004 respectively that ultrasound has a strong anti-scaling effect. The reason for scale prevention is that the scaling substances in the fluid are dispersed and detached under the strong sound field, and it is not easy to stay on the pipe wall to form scale. Gradually, ultrasonic descaling and anti-scaling equipment began to be widely used in various industrial or civil pipelines, water purification and other fields, such as water scaling in factory cooling systems, reducing the formation of scale on the inner wall of pipelines, and used for lake management, inhibiting bacteria and algae, preventing the formation of biological scale, cleaning water quality, saving chemicals, and reducing sewage discharge.

[0008] Ultrasonic descaling and anti-scaling equipment mainly consists of an ultrasonic generator, an ultrasonic signal transmission cable, an ultrasonic energy converter, and a pipe assembly with an ultrasonic transducer installed. According to the installation method, it is divided into three types: external, embedded, and built-in. Ultrasonic descaling and anti-scaling equipment mainly uses the "cavitation" effect, "chemical" effect, "shear" effect, and "inhibition" effect of ultrasound to treat the fluid with a strong sound field, so that the scaling substances in the fluid undergo a series of changes in their physical form and chemical properties under the action of the ultrasonic field, so that they are dispersed, crushed, loosened, and not easy to adhere to the pipe wall to form scale.

[0009] The "cavitation" effect is that the energy of ultrasound directly generates a large number of cavities and bubbles in the treated fluid medium. When these cavities and bubbles are broken and squeezed, a strong pressure peak is generated in a certain range. The local pressure peak can reach thousands of atmospheres. Under the action of the pressure peak, the scaling substances are crushed and suspended in the water, and the scale layer that has been generated is broken up to make it easy to fall off; the "activation" effect is that ultrasound produces "cavitation" in the fluid, while increasing the activity of the flowing fluid and scaling substances, destroying the conditions for scale formation and deposition on the heat exchanger tube wall, so that the scaling substances form dispersed deposits in the fluid instead of forming hard scale on the tube wall; the "shear" effect is that ultrasound radiates on the scale layer, tube wall and water. Due to the different responses to the ultrasonic frequency, the three produce asynchronous vibrations, thus generating high-speed relative motion. Due to the speed difference, the relative shear force on the interface between the scale layer and the heat exchanger tube wall is formed, which causes the scale layer to fatigue and loosen; the "inhibition" effect is to change the physical and chemical properties of the fluid body through the action of ultrasound, which can inhibit the nucleation and growth of ions in the medium at the wall surface, thereby reducing the number of scale-forming ions adhering to the heat exchanger surface. Practical research has shown that the longer the ultrasonic action time, the better the effect of preventing scaling of scaling substances. In short, when the medium is under the action of ultrasound, when the ultrasonic energy is large enough, that is, "power ultrasound" can produce a short, local, extremely high temperature, high pressure, and high-strength electric field extreme physical environment in the conductive medium under normal temperature and pressure conditions, the fluid will produce the so-called "acoustic cavitation effect" and trigger many mechanical, physical, chemical, biological and other effects, achieving the purpose of ultrasonic anti-scaling and descaling in the fluid.

[0010] Fouling resistance, also known as fouling coefficient, indicates the degree of heat transfer efficiency reduction caused by deposits on the heat transfer surface of the heat exchanger, that is, the heat transfer resistance caused by the deposits on the heat transfer surface, and the unit is m 2 ·K / W. The heat exchange surface of the heat exchanger is covered with some kind of dirt (such as scale, sludge, oil, etc.). The gradual formation of dirt thermal resistance will inevitably lead to a corresponding decrease in the heat transfer coefficient of the heat exchanger, causing the heat transfer performance of the heat exchanger to deteriorate. Due to the existence of dirt thermal resistance, the heat transfer coefficient decreases, the required heat transfer area increases, the economic efficiency of the equipment decreases, and sometimes seriously affects the normal operation of the equipment.

[0011] The earliest calculation relationship for the formation of scale in tubular heat exchangers was proposed by Albert Pencher of the United Kingdom, which is called the Albert Pencher equation, as shown in formula (1). The corresponding numerical values ​​are obtained by calculating the corresponding parameters to determine the scale formation. Once scale is formed, the heat scale coefficient of the heat exchanger will increase. When the heat scale coefficient increases to a certain extent, the performance of the heat exchanger will be seriously affected.

[0012]

[0013] Where: r is the fouling thermal resistance on the tube side (m 2 ·K / W); t is time (s); α is the calculation constant in the Albert-Pancher formula; Re is the tube side Reynolds number; E is the energy coefficient in the Albert-Pancher formula; R is the gas constant; T f is the liquid film temperature (K); γ is the calculation constant in the Albert-Panchel formula; τ is the shear force on the dirt surface (Pa).

[0014] It can be seen from the formula that the speed of fouling formation is directly related to the fluid velocity and the liquid film temperature. However, the Albert Panchel calculation constant (α) and energy coefficient (E) values ​​in the formula need to be reset according to the actual conditions of the reactor and the reaction materials in actual applications.

[0015] By analyzing the dynamic parameters of the heat exchanger inlet and outlet temperature, flow rate, pressure, etc., and through parameter simulation calculation, a heat exchanger scaling prediction model is established to judge the scaling situation as an important basis for control system regulation. In the design stage, a reasonable range of fouling thermal resistance is set through a large number of statistical calculations, and the control system automatically takes appropriate measures to control it.

[0016] At present, the existing ultrasonic anti-scaling technology is mostly used for the effect on inorganic scale compounds, and is rarely used for the removal of organic scale substances. In particular, there is no relevant report on the design of the heat exchanger of the kettle reactor for the process of ethylene polymerization to produce 1-butene and 1-octene. Further research is needed on the installation position of the ultrasonic transducer in the reactor, the adjustment effect of the transducer and other designs on the removal of oligomers. In addition, the online real-time monitoring technology of ultrasonic anti-scaling is rarely used in the existing technology. It is of great practical significance to timely monitor the scaling of the heat exchanger online to play a good role in regulating the operation of the device. Summary of the invention

[0017] The purpose of the present invention is to provide a kettle reactor with the function of online polymer removal and its application; the kettle reactor is an ethylene polymerization reactor for producing 1-butene and 1-octene.

[0018] In order to improve the difficulty of regular manual cleaning of oligomers accumulated in the heat exchanger in the process of ethylene oligomerization to synthesize 1-butene / 1-octene, the reactor is equipped with an online self-cleaning function and the ethylene polymerization capacity is improved, so that the reaction device of ethylene dimerization and tetramerization can be operated stably and at low cost for a long time; the present invention applies ultrasonic online cleaning technology to the kettle reactor of the process, and achieves the purpose of preventing and removing oligomers from adhering to the heat exchanger through the cavitation, activation, shearing and inhibition effects of ultrasonic waves. Ultrasonic waves can remove dirt in heat exchange media with different components by preventing the scale layer from adhering to the surface of the heat exchange tube. The high-speed vortex caused by ultrasonic waves can effectively destroy the stagnant layer. This principle can improve the heat transfer effect. Ultrasonic anti-scaling and descaling not only has low energy consumption but also low operating costs, and can effectively reduce the workload of routine maintenance. No chemical substances need to be added during the descaling process, which will not cause environmental pollution and waste of resources, will not damage the equipment, and will not threaten the health of the staff. In addition, it also has the advantages of continuous operation, high degree of automation, safety and environmental protection. The ultrasonic wave has an acoustic field effect on the scaling substances, so that they are dispersed and fall off, and are not easy to stay on the tube wall to form scaling. The present invention installs ultrasonic transducers around the inner wall of the reactor, and prevents the low molecular polymers produced by the reaction from adhering to the heat exchange tubes through the ultrasonic oscillation, thereby realizing the long-term stable operation of the polymerization reactor.

[0019] In order to achieve the above purpose, the present invention adopts the following technical solutions:

[0020] In one aspect, the present invention provides a tank reactor with a polymer online removal function, wherein the tank reactor comprises: a reactor shell, a heat exchanger, an agitator, an ultrasonic transducer and an ultrasonic generator;

[0021] The stirring shaft of the stirrer is arranged at the center axis position in the reactor;

[0022] A plurality of the heat exchangers are arranged in the reactor around the stirring shaft;

[0023] The ultrasonic transducer is mounted on the reactor housing and is located between the inner wall of the reactor and the heat exchanger;

[0024] The ultrasonic generator is located outside the reactor and is electrically connected to the ultrasonic transducer.

[0025] The installation position of the ultrasonic transducer will directly affect the descaling effect of the heat exchanger. The present invention chooses to install it between the inner wall of the reactor and the heat exchange tube. The heat exchangers in the kettle reactor are divided into multiple groups, symmetrically or evenly distributed, and installed vertically. Usually, the accumulation thickness of the polymer hanging on the heat exchange tube at the lateral tube wall of the reactor is greater, because the flushing effect of the stirring paddle on the side of the kettle wall is weakened at the kettle wall. Therefore, the present invention is designed to build-in the ultrasonic transducer and install it between the inner wall of the reactor and the heat exchanger, so that the ultrasonic wave can directly act on the inner wall of the heat exchanger.

[0026] According to the kettle reactor of the present invention, preferably, the ultrasonic transducer is connected to the reactor housing via a flange, and a cable is led out from the middle of the flange and connected to the ultrasonic generator.

[0027] According to the kettle reactor of the present invention, preferably, the ultrasonic transducer comprises a plurality of ultrasonic transducers installed on the side walls of the reactor shell and at least one ultrasonic transducer installed on the bottom of the reactor shell.

[0028] The bottom of the reactor is also equipped with an ultrasonic transducer, which is mainly used to remove adhesions on the bottom of the heat exchanger and the central stirring paddle, and works in conjunction with the ultrasonic transducer on the side wall to ensure the descaling effect. Specifically, the number of installations at the bottom can be 1, 2 or more.

[0029] Specifically, the ultrasonic transducers are symmetrically or evenly distributed in the cross section, and in the longitudinal direction, multiple rows can also be arranged according to the specific size of the reactor.

[0030] According to the kettle reactor of the present invention, preferably, in the longitudinal direction, the spacing between the plurality of ultrasonic transducers installed on the side wall of the reactor shell is 20 to 50 cm, and they can be distributed with equal spacing or unequal spacing. The installation spacing at the upper part of the side wall of the reactor shell can be slightly larger, and the installation spacing at the lower part of the side wall of the reactor shell can be reduced.

[0031] According to the kettle reactor of the present invention, preferably, the ultrasonic transducer installed on the upper part of the side wall of the reactor shell is inclined at 20° to 45° with respect to the horizontal direction toward the heat exchanger.

[0032] According to the kettle reactor of the present invention, preferably, the ultrasonic transducer installed at the bottom of the reactor shell is inclined at 40° to 90° with respect to the horizontal direction toward the heat exchanger.

[0033] The directivity of the ultrasonic sound field is directly related to the radius of the ultrasonic transducer. The directivity of the ultrasonic sound field decreases as the radius of the ultrasonic transducer increases. Preferably, the radius of the ultrasonic transducer is 15 to 80 mm, and more preferably 25 to 45 mm.

[0034] The directivity of the ultrasonic sound field gradually increases with the decrease of the frequency. Preferably, the frequency of the ultrasonic transducer is 20 to 60 kHz, more preferably 28 to 35 kHz, to achieve the best scale inhibition effect.

[0035] Ultrasonic waves will be affected by the temperature changes in the reactor and affect the descaling effect. Ultrasonic cavitation is best within the temperature range of 40 to 60°C. The reaction temperature of ethylene tetramerization to synthesize 1-octene is in the range of 50 to 55°C, which is within the optimal range for the use of ultrasound.

[0036] Ultrasonic transducers are usually high-power, pressure-resistant transducers. Power density is an important parameter for characterizing ultrasound. Power density = transmission power (W) / transmission area (S). Preferably, the power density of the ultrasonic transducer is greater than 3W / cm 2 , more preferably 30 to 50 W / cm 2 .

[0037] According to the tank reactor of the present invention, preferably, the tank reactor further comprises a control unit and a monitor;

[0038] The monitor monitors and adjusts in real time: the temperature and flow rate of the heat exchange fluid in the heat exchanger, the feed flow rate and the discharge flow rate of the reactor, and the flow rate of the reflux material in the reactor;

[0039] The monitor transmits the real-time monitoring data to the control unit, and the control unit processes the received data signal to obtain the real-time corrected scale thermal resistance R (m) , and according to the real-time correction scale thermal resistance R (m) Real-time feedback instructs the monitor to adjust various parameters;

[0040] When the kettle reactor starts working, part of the ultrasonic transducers are turned on, and the rest are kept as standby;

[0041] The specific feedback instruction process includes:

[0042] When the control unit processes the obtained real-time corrected scale thermal resistance R (m) When the value is 10-15, it is considered that a small amount of scale is generated in the heat exchanger, which is determined to be level one. The monitor will be fed back in real time to instruct the feed flow rate of the reactor to decrease by 5%-10%, and the power of the ultrasonic transducer will be increased by 10%-20%;

[0043] When the control unit processes the obtained real-time corrected scale thermal resistance R (m) When the value is 16-20, it is considered that the heat exchanger has a moderate amount of scale, which is determined to be level 2. The monitor will be fed back in real time to instruct the reactor to reduce the feed flow rate by 10%-30%, and increase the power of the ultrasonic transducer by 20%-40%.

[0044] When the control unit processes the obtained real-time corrected scale thermal resistance R (m) When the value is ≥21, it is considered that the heat exchanger has a lot of scale, which is determined to be level 3. The monitor will be fed back in real time to instruct the reactor to reduce the feed flow rate by 30% to 50%, increase the power of the ultrasonic transducer by 20% to 40%, and enable the standby ultrasonic transducer to improve the descaling ability.

[0045] The real-time corrected scale thermal resistance R (m) The calculation process is as follows:

[0046]

[0047] Where m is the correction coefficient, m is 1.706×10 11 ;

[0048] r is the fouling thermal resistance on the tube side, in m 2 K / W;

[0049] t is time, in seconds;

[0050]

[0051] Where α is the calculation constant in Albert Panchel's formula, which is 8.39m 2 ·K / (W·s);

[0052] k is the calibration constant, k is 3.01×10 6 ;

[0053] Re is the Reynolds number of the stirring blade. The Reynolds number physically represents the ratio of the inertial force to the viscous force level;

[0054] E is the energy coefficient in Albert Panchel's formula, which is taken as 68 kJ / mol;

[0055] R is the gas constant, which is 8.314×10 -3 kJ / mol;

[0056] T f is the liquid film temperature, in K, and is the discharge temperature of the monitored reactor;

[0057] γ is the calculation constant in Albert Panchel's formula, which is 4.03×10 -11 kJ / mol;

[0058] τ is the shear force on the dirt surface, in Pa;

[0059]

[0060] Where ρ is the density of the reaction fluid, in kg / m 3 ;

[0061] d j is the impeller diameter of the stirring paddle, in m;

[0062] n is the impeller speed of the stirring paddle, in r / s, obtained by the set stirring rate of the stirring paddle;

[0063] μ is the kinematic viscosity of the reaction fluid, in Pa·s;

[0064] τ=(f / 2)ρv 2

[0065] Where ρ is the density of the reaction fluid, in kg / m 3 ;

[0066] v is the speed at which the stirring paddle drives the reaction fluid, in m / s;

[0067] v=πd j n

[0068] f is the friction coefficient, f = 0.0791 / Re 0.25 .

[0069] Among them, when the kettle reactor starts working, part of the ultrasonic transducers are turned on, and the rest are used as backup; the ultrasonic transducers turned on specifically when starting working and the backup ultrasonic transducers can be freely selected, for example, turned on alternately from top to bottom, or turned on one and closed the other, and the present invention has no limitation on this.

[0070] Those skilled in the art understand that the signal input of the monitor comes from a flow meter, a temperature sensor, a pressure sensor, etc., that is, the monitor monitors various parameters in real time through a flow meter, a temperature sensor, a pressure sensor, etc.

[0071] According to the tank reactor of the present invention, preferably, the monitors include: a feed monitor, a discharge monitor, a reflux material monitor, a heat exchanger inlet monitor and a heat exchanger outlet monitor; these monitors monitor the temperature, flow rate and pressure at various locations.

[0072] Further preferably, the monitor further comprises a product monitor and a stirring monitor; and the feed monitor comprises a first feed monitor and a second feed monitor.

[0073] The specific monitors are flow meters, temperature sensors, pressure sensors, speed sensors, etc. For example, the cooling water flow rate in the heat exchange tube of the heat exchanger is 50-100 kg / h (flow rate 1 m / s), and the inlet water temperature is controlled at 30°C-35°C. The water flow rate is measured by the flow meter, and the sensor monitors the inlet and outlet water temperatures.

[0074] According to the kettle reactor of the present invention, preferably, the control unit monitors the change of the resonant frequency of the ultrasonic transducer in real time and adjusts the output frequency of the ultrasonic transducer in real time. Specifically, the transducer and the tuning capacitor are connected in series to form a series resonant circuit, and the resonance point is set at a fixed frequency of the transducer. When the output frequency is equal to the resonant frequency, the current is maximum and the conversion efficiency of the transducer is highest. Specifically, a high-frequency current inductor is used to monitor the resonant current of the ultrasonic transducer, and the output frequency is adjusted in real time to ensure that the transducer is in the best resonant state, thereby realizing the automatic tuning function.

[0075] According to the tank reactor of the present invention, preferably, the control unit further comprises a display module, and the display module is used to display the parameters received by the control unit and the state of the control unit. The display module is specifically a display. In addition, the control unit comprises a calculation module, which is used to process the received signal and obtain the real-time scaling coefficient r.

[0076] The tank reactor of the present invention is an ethylene polymerization reactor for producing 1-butene and 1-octene. In a specific application process, the discharge of the reactor after the reaction of the feed first enters the catalyst termination tank, then enters the product tower through the flash tank, and a part of the unreacted ethylene material returns to the reactor through the cooling reflux tank. The control unit can also further detect and adjust the ethylene material input, the operation of the ultrasonic transducer, the water flow rate and temperature of the heat exchanger, and the stirring operation speed and time, and the various components work in a coordinated manner.

[0077] Another invention of the present invention provides one or more autoclave reactors with online polymer removal function for use in the process of ethylene oligomerization to synthesize 1-butene and / or 1-octene.

[0078] The beneficial effects of the present invention include:

[0079] 1) Ultrasonic waves can remove dirt from heat exchange media with different compositions by preventing the scale layer from adhering to the surface of the heat exchanger. The high-speed vortex caused by ultrasonic waves can effectively destroy the stagnant layer and improve the heat transfer effect. Ultrasonic anti-scaling and descaling not only has low energy consumption but also low operating costs, and can effectively reduce the workload of routine maintenance.

[0080] By installing an ultrasonic transducer between the wall of the 1-butene / 1-octene reactor and the heat exchanger, the cavitation effect, activation effect and shear effect of the ultrasonic wave are used to prevent the low molecular polymers produced by the reaction from adhering to the heat exchanger, thereby improving the heat exchange efficiency of the heat exchanger. Since once the temperature of the reactor is overheated, the reactor needs to be switched to clean the heat exchanger. By using the reactor with ultrasonic wave to prevent polymer adhesion of the present invention, the operation cycle of switching the reactor to clean the heat exchange tube is increased from the original 5 to 7 days to more than 30 days.

[0081] 2) The online control unit controls the operation of the ultrasonic transducer in real time by monitoring the temperature and flow of the heat exchanger and the input of ethylene materials, thereby improving the working efficiency of the transducer and preventing and removing the oligomers adhering to the heat exchanger.

[0082] 3) The installation position of the transducer effectively controls the generation of adhesion oligomers on the heat exchanger and achieves the effect of timely removal. BRIEF DESCRIPTION OF THE DRAWINGS

[0083] Figure 1 It is a kettle reactor with the function of online polymer removal of the present invention;

[0084] Figure 2 It is a cross-sectional schematic diagram of the installation of an ultrasonic transducer inside a kettle reactor of the present invention;

[0085] Figure 3 It is a schematic diagram of installing the bottom ultrasonic transducer of the kettle reactor of the present invention;

[0086] Figure 4 It is a control system framework diagram of the tank reactor of the present invention;

[0087] Figure 5 This is the process flow / control diagram for the production of 1-butene / 1-octene.

[0088] Wherein, the reference numerals are:

[0089] 1. The first preheater;

[0090] 2. Second preheater;

[0091] 3-1, first feed monitor;

[0092] 3-2, second feed monitor;

[0093] 3-3. Heat exchanger outlet monitor;

[0094] 3-4. Heat exchanger inlet monitor;

[0095] 3-5. Stirring monitor;

[0096] 3-6. Discharging monitor;

[0097] 3-7. Reflux material monitor;

[0098] 3-8. Product monitor;

[0099] 4. The first compressor;

[0100] 5. Cooler;

[0101] 6. Feed pump;

[0102] 7. Agitator;

[0103] 8. Reactor;

[0104] 8-1. Heat exchanger;

[0105] 8-2, ultrasonic transducer;

[0106] 8-3, reactor shell side wall;

[0107] 8-4, bottom of reactor shell;

[0108] 9. Ultrasonic generator;

[0109] 10. Control unit;

[0110] 11. Second compressor;

[0111] 12. Catalyst termination tank;

[0112] 13. Cooling reflux tank;

[0113] 14. Flash tank;

[0114] 15. Product tower. DETAILED DESCRIPTION

[0115] In order to explain the present invention more clearly, the present invention is further described below in conjunction with preferred embodiments. It should be understood by those skilled in the art that the following specific description is illustrative rather than restrictive, and should not be used to limit the scope of protection of the present invention.

[0116] like Figure 1 As shown, the tank reactor with the polymer online removal function provided by the present invention comprises: a reactor shell, a heat exchanger 8-1, an agitator 7, an ultrasonic transducer 8-2 and an ultrasonic generator 9;

[0117] The stirring shaft of the stirrer 7 is arranged at the central axis position in the reactor;

[0118] A plurality of heat exchangers 8-1 are arranged around the stirring shaft in the reactor;

[0119] The ultrasonic transducer 8-2 is mounted on the reactor housing and is located between the inner wall of the reactor and the heat exchanger 8-1;

[0120] The ultrasonic generator 9 is located outside the reactor and is electrically connected to the ultrasonic transducer 8 - 2 .

[0121] The installation position of the ultrasonic transducer 8-2 will directly affect the descaling effect of the heat exchanger 8-1. The present invention chooses to install it between the inner wall of the reactor and the heat exchange tube. The heat exchangers in the kettle reactor are divided into multiple groups, symmetrically or evenly distributed, and installed vertically. Usually, the accumulation thickness of the polymer hanging on the heat exchange tube at the lateral tube wall of the reactor is greater, because the flushing effect of the stirring paddle on the side of the kettle wall becomes weaker at the kettle wall. Therefore, the present invention is designed to build-in the ultrasonic transducer 8-2 and install it between the inner wall of the reactor and the heat exchanger 8-1, so that the ultrasonic wave can directly act on the inner wall of the heat exchanger.

[0122] In a preferred embodiment of the present invention, Figure 1 As shown, the ultrasonic transducer 8-2 is connected to the reactor housing through a flange, and a cable is led out from the middle of the flange to connect to the ultrasonic generator 9. The flange connection with the reactor ensures the sealing of the reactor.

[0123] like Figure 1-Figure 3 As shown, in a preferred embodiment of the present invention, the ultrasonic transducer 8-2 includes a plurality of ultrasonic transducers installed on the side wall 8-3 of the reactor shell, and at least one ultrasonic transducer installed on the bottom 8-4 of the reactor shell.

[0124] like Figure 3 As shown, an ultrasonic transducer 8-2 is also installed at the bottom of the reactor, which is mainly used to remove adhesions on the bottom of the heat exchanger and the central stirring paddle, and works in conjunction with the ultrasonic transducer on the side wall to ensure the descaling effect. Specifically, the number of installations at the bottom can be 1, 2 or more.

[0125] Specifically, Figure 2 As shown, the ultrasonic transducers 8-2 are symmetrically or evenly distributed in the cross section, and can also be arranged in multiple rows in the longitudinal direction according to the specific size of the reactor. Preferably, in the longitudinal direction, the spacing between the multiple ultrasonic transducers 8-2 installed on the side wall of the reactor shell is 20 to 50 cm, and they can be distributed with equal or unequal spacing. For example, Figure 1 In the embodiment, the installation spacing of the upper part of the reactor shell side wall can be slightly larger, and the installation spacing of the lower part of the reactor shell side wall can be reduced. More preferably, as Figure 1 As shown, the ultrasonic transducer 8-2 installed on the upper side wall of the reactor shell is inclined at 20° to 45° to the horizontal direction toward the heat exchanger 8-1; the ultrasonic transducer 8-2 installed on the bottom of the reactor shell is inclined at 40° to 90° to the horizontal direction toward the heat exchanger 8-1; to ensure that all ultrasonic transducers 8-2 are as close to the heat exchanger 8-1 as possible.

[0126] The directivity of the ultrasonic sound field is directly related to the radius of the ultrasonic transducer. The directivity of the ultrasonic sound field decreases as the radius of the ultrasonic transducer increases. Preferably, the radius of the ultrasonic transducer 8-2 is 15 to 80 mm, and more preferably 25 to 45 mm.

[0127] The directivity of the ultrasonic sound field gradually increases with the decrease of the frequency. Preferably, the frequency of the ultrasonic transducer 8-2 is 20 to 60 kHz, and more preferably 28 to 35 kHz, to achieve the best scale inhibition effect.

[0128] Ultrasonic waves will be affected by the temperature changes in the reactor and affect the descaling effect. Ultrasonic cavitation is best within the temperature range of 40 to 60°C. The reaction temperature of ethylene tetramerization to synthesize 1-octene is in the range of 50 to 55°C, which is within the optimal range for the use of ultrasound.

[0129] Ultrasonic transducers are usually high-power, pressure-resistant transducers. Power density is an important parameter for characterizing ultrasound. Power density = transmission power (W) / transmission area (S); preferably, the power density of the ultrasonic transducer 8-2 is greater than 3W / cm 2 , more preferably 30 to 50 W / cm 2 .

[0130] like Figure 4 and Figure 5 As shown, the tank reactor further includes a control unit 10 and a monitor;

[0131] The monitor monitors and adjusts in real time: the temperature and flow rate of the heat exchange fluid in the heat exchanger 8-1, the feed flow rate and the discharge flow rate of the reactor 8, and the flow rate of the reflux material in the reactor 8;

[0132] The monitor transmits the real-time monitoring data to the control unit 10, and the control unit 10 processes the received data signal to obtain the real-time corrected scale thermal resistance R (m) (calculation module in the control unit), and correct the scale thermal resistance R in real time (m) Real-time feedback instructs the monitor to adjust various parameters;

[0133] When the kettle reactor starts working, part of the ultrasonic transducers are turned on, and the rest are kept as standby;

[0134] The specific feedback instruction process includes:

[0135] When the control unit processes the obtained real-time corrected scale thermal resistance R (m)When the value is 10-15, it is considered that a small amount of scale is generated in the heat exchanger, which is determined to be level one. The monitor will be fed back in real time to instruct the feed flow rate of the reactor to decrease by 5%-10%, and the power of the ultrasonic transducer will be increased by 10%-20%;

[0136] When the control unit processes the obtained real-time corrected scale thermal resistance R (m) When the value is 16-20, it is considered that the heat exchanger has a moderate amount of scale, which is determined to be level 2. The monitor will be fed back in real time to instruct the reactor to reduce the feed flow rate by 10%-30%, and increase the power of the ultrasonic transducer by 20%-40%.

[0137] When the control unit processes the obtained real-time corrected scale thermal resistance R (m) When the value is ≥21, it is considered that the heat exchanger has a lot of scale, which is determined to be level 3. The monitor will be fed back in real time to instruct the reactor to reduce the feed flow rate by 30% to 50%, increase the power of the ultrasonic transducer by 20% to 40%, and enable the standby ultrasonic transducer to improve the descaling ability.

[0138] The real-time corrected scale thermal resistance R (m) The calculation process is as follows:

[0139]

[0140] Where m is the correction coefficient, m is 1.706×10 11 ;

[0141] r is the heat resistance of dirt on the tube side, in m 2 K / W;

[0142] t is time, in seconds;

[0143]

[0144] Where α is the calculation constant in Albert Panchel's formula, which is 8.39m 2 ·K / (W·s);

[0145] k is the calibration constant, k is 3.01×10 6 ;

[0146] Re is the Reynolds number of the stirring blade. The Reynolds number physically represents the ratio of the inertial force to the viscous force level;

[0147] E is the energy coefficient in Albert Panchel's formula, which is taken as 68 kJ / mol;

[0148] R is the gas constant, which is 8.314×10 -3 kJ / mol;

[0149] T f is the liquid film temperature, in K, and is the discharge temperature of the monitored reactor;

[0150] γ is the calculation constant in Albert Panchel's formula, which is 4.03×10 -11 kJ / mol;

[0151] τ is the shear force on the dirt surface, in Pa;

[0152]

[0153] Where ρ is the density of the reaction fluid, in kg / m 3 ;

[0154] d j is the impeller diameter of the stirring paddle, in m;

[0155] n is the impeller speed of the stirring paddle, in r / s, obtained by the set stirring rate of the stirring paddle;

[0156] μ is the kinematic viscosity of the reaction fluid, in Pa·s;

[0157] τ=(f / 2)ρv 2

[0158] Where ρ is the density of the reaction fluid, in kg / m 3 ;

[0159] v is the speed at which the stirring paddle drives the reaction fluid, in m / s;

[0160] v=πd j n

[0161] f is the friction coefficient, f = 0.0791 / Re 0.25 .

[0162] Among them, when the kettle reactor starts working, part of the ultrasonic transducers are turned on, and the rest are used as backup; the ultrasonic transducers turned on specifically when starting working and the backup ultrasonic transducers can be freely selected, for example, turned on alternately from top to bottom, or turned on one and closed the other, and the present invention has no limitation on this.

[0163] Those skilled in the art understand that the signal input of the monitor comes from a flow meter, a sensor, etc., that is, the monitor monitors various parameters in real time through a flow meter, a sensor, etc.

[0164] Preferably, the monitors include: a feed monitor, a discharge monitor 3-6, a reflux monitor 3-7, a heat exchanger inlet monitor 3-4, and a heat exchanger outlet monitor 3-3, for monitoring the temperature, flow rate and pressure at various locations.

[0165] Further preferably, the monitor further comprises a product monitor 3-8 and a stirring monitor 3-5; the feed monitor comprises a first feed monitor 3-1 and a second feed monitor 3-2.

[0166] The specific monitoring devices are flow meters, temperature sensors, pressure sensors, speed sensors, etc. For example, the cooling water flow rate in the heat exchange tube of the heat exchanger 8-1 is 50-100 kg / h (flow rate 1 m / s), and the inlet water temperature is controlled at 30°C-35°C. The flow rate of water is measured by the flow meter, and the sensor monitors the inlet and outlet water temperatures.

[0167] Preferably, the control unit 10 monitors the change of the resonant frequency of the ultrasonic transducer 8-2 in real time, and adjusts the output frequency of the ultrasonic transducer 8-2 in real time. Specifically, the transducer and the tuning capacitor are connected in series to form a series resonant circuit, and the resonance point is set at a fixed frequency of the transducer. When the output frequency is equal to the resonant frequency, the current is maximum and the conversion efficiency of the transducer is highest. Specifically, a high-frequency current inductor is used to monitor the resonant current of the ultrasonic transducer 8-2, and the output frequency is adjusted in real time to ensure that the transducer is in the best resonant state, thereby realizing the automatic tuning function.

[0168] Further preferably, the control unit 10 further comprises a display module, and the display module is used to display the parameters received by the control unit 10 and the state of the control unit 10. The display module is specifically a display.

[0169] The reactor 8 of the present invention is an ethylene polymerization reactor for producing 1-butene and 1-octene. In a specific application process, the discharge of the reactor after the reaction of the feed first enters the catalyst termination tank 12, and then enters the product tower 15 through the flash tank 14, and a part of the unreacted ethylene material returns to the reactor 8 through the cooling reflux tank 13. The control unit 10 can also be used to further detect and adjust the ethylene material input, the operation of the ultrasonic transducer, the water flow rate and temperature of the heat exchanger, and the stirring operation speed and time, etc., and each component program works in coordination.

[0170] The reactor and the process device for ethylene polymerization of the present invention also include other accessories such as power supplies, valves, pumps, etc., which are used to enable the normal operation of monitors, heat exchangers, etc., and to adjust parameters such as the flow rate and pressure of the heat exchange fluid.

[0171] like Figure 5As shown, when the reactor of the present invention is specifically used in ethylene polymerization reaction, the ethylene raw material (feed 1) is injected from the upper part of the reactor 8 through the first compressor 4 after passing through the first preheater 1. At the same time, the catalyst and the reaction solvent (feed 2) are injected from the lower part of the reactor through the feed pump 6 after passing through the second preheater 2. The agitator 7 starts to work to accelerate the reaction between the raw material and the catalyst and the reaction solvent. At the same time, the cooling water circulation of the heat exchanger 8-1 works to cool the reaction of the materials in the reactor 8. There is a cooler 5 on the cooling water circulation pipeline; the ultrasonic transducer 8-2 also works in coordination with the ultrasonic generator 9 at the same time, and the control unit 10 collects the data of each position online in real time (the collection of the data of each position includes the first feed monitor 3-1, the second feed monitor 3-2, the heat exchanger outlet monitor 3-3, the heat exchanger inlet monitor 3-4, the stirring monitor 3-5, the discharge monitor 3-6, the reflux material monitor 3-7, and the product monitor 3-8), collects and processes the signals, and obtains the real-time corrected scale thermal resistance R (m) , real-time control of the feed liquid inlet and outlet amounts, inlet and outlet temperatures, cooling water inlet and outlet temperatures, water volume, etc., to maintain the balance of the reaction system.

[0172] Among them, the discharge of the reactor 8 after the reaction first enters the catalyst termination tank 12, and then enters the product tower 15 through the flash tank 14, and a part of the unreacted ethylene material passes through the reflux tank 13 and the second compressor 11 to return to the reactor 8. Therefore, by adjusting the control program, the ethylene material input, the operation of the ultrasonic transducer, the water flow and temperature of the heat exchanger, and the stirring operation speed and time, etc. are reasonably controlled, and the various component programs work in coordination.

[0173] Application Example 1

[0174] use Figure 5 The ethylene oligomerization reaction system and control system are used to tetramerize ethylene to synthesize 1-octene, wherein 1-octene is produced by homogeneous catalytic tetramerization of ethylene in liquid cyclohexane, wherein the reactor uses Figure 1-Figure 3 The specific structure of the catalyst is obtained by the interaction of chromium acetylacetonate, (diphenyl)phosphine nitrogen (cyclopropyl)phosphine (diphenyl) ligand, and methylaluminoxane (MAO). In the ethylene tetramerization process, the reaction pressure is 5.0 MPa and the reaction temperature is 55°C.

[0175] The reactor adopts four groups of vertical heat exchangers 8-1, and the cooling water flow of each group is controlled separately. Five groups (5 rows from top to bottom, 8 in each horizontal row, and 2 at the bottom) of the built-in ultrasonic transducers 8-2 of the present invention are installed and installed at the heat exchange tubes of the reactor respectively. The ultrasonic generator 9 used in the reactor is an ultrasonic generator produced by Beijing Zhonghuan Xinke Technology Co., Ltd., using 220V AC voltage, 200W power, ultrasonic frequency range of 20kHz, and pulse period of 100ms. After the device is put into use with the catalyst, the ultrasonic generators 9 corresponding to the second and fourth groups of ultrasonic transducers of the present invention are started. When the device is continuously operated for 14 days, the scale thermal resistance R is corrected in real time. (m) The displayed value is 12, indicating that a small amount of polyethylene scale is generated on the heat exchange tube, which is determined to be level one. The real-time feedback instruction monitor is used to reduce the feed flow rate of the reactor by 5%, and at the same time increase the power of the ultrasonic transducer by 10%. After about 24 hours, the scale thermal resistance R is corrected in real time. (m) The values ​​are stable, the growth trend is controlled, and the original feed amount and the power set by the original ultrasonic transducer are gradually restored.

[0176] Comparative Example 1:

[0177] Comparison is made with Application Example 1 without using an ultrasonic device. The comparison results are shown in Table 1 below:

[0178] Table 1

[0179]

[0180] As can be seen from Table 1, after the ultrasonic device is installed, the operation cycle of the reactor is significantly extended from the original 7 days to 31 days, which effectively reduces the operating cost and increases the operating stability of the device.

[0181] Application Example 2:

[0182] use Figure 5 The ethylene oligomerization reaction system and control system are used to trimerize ethylene into 1-hexene and to produce 1-butene by homogeneous catalytic dimerization of ethylene, wherein the reactor uses Figure 1-Figure 3 The specific structure of the catalyst is obtained by the interaction of Ti(OR)4 titanate, ether modifier and aluminoxane. In the ethylene dimerization process, the reaction pressure is 2.5MPa and the reaction temperature is 50℃.

[0183] The reactor adopts four groups of vertical heat exchangers 8-1, and the cooling water flow of each group is controlled separately. Five groups (5 rows from top to bottom, 8 in each horizontal row, and 2 at the bottom) of the built-in ultrasonic transducers 8-2 of the present invention are installed and respectively installed at the heat exchange tubes of the reactor. The ultrasonic generator 9 used in the reactor is an ultrasonic generator produced by Beijing Zhonghuan Xinke Technology Co., Ltd., using 220V AC voltage, 200W power, ultrasonic frequency range of 20kHz, and pulse period of 100ms. After the device is put into use with the catalyst, the ultrasonic generator 9 corresponding to the second and fourth groups of ultrasonic transducers of the present invention is started. When the device is continuously operated for 20 days, the scale thermal resistance R is corrected in real time. (m) The displayed value is 13, indicating that a small amount of polyethylene scale is generated on the heat exchange tube, which is determined to be level one. The real-time feedback instruction monitor is used to reduce the feed flow rate of the reactor by 5%, and at the same time increase the power of the ultrasonic transducer by 10%. After about 24 hours, the scale thermal resistance R is corrected in real time. (m) The values ​​are stable, the growth trend is controlled, and the original feed amount and the power set by the original ultrasonic transducer are gradually restored.

[0184] Comparative Example 2:

[0185] Comparison is made with Application Example 2 without using an ultrasonic device. The comparison results are shown in Table 2 below:

[0186] Table 2

[0187]

[0188] As can be seen from Table 2, the installation of an ultrasonic anti-scaling polyethylene device significantly extended the reactor operation cycle from the original 10 days to 46 days, effectively reducing the operating cost and increasing the operating stability of the device.

[0189] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not limitations on the implementation methods of the present invention. For ordinary technicians in the relevant field, other different forms of changes or modifications can be made based on the above description. It is impossible to list all the implementation methods here. All obvious changes or modifications derived from the technical solution of the present invention are still within the protection scope of the present invention.

Claims

1. A tank reactor with a polymer online removal function, wherein: The kettle reactor comprises: a reactor shell, a heat exchanger, a stirrer, an ultrasonic transducer and an ultrasonic generator; The stirring shaft of the stirrer is arranged at the center axis position in the reactor; A plurality of the heat exchangers are arranged in the reactor around the stirring shaft; The ultrasonic transducer is mounted on the reactor housing and is located between the inner wall of the reactor and the heat exchanger; The ultrasonic generator is located outside the reactor and is electrically connected to the ultrasonic transducer.

2. The tank reactor according to claim 1, wherein The ultrasonic transducer is connected to the reactor shell through a flange, and a cable is led out from the middle of the flange and connected to the ultrasonic generator.

3. The tank reactor according to claim 1, wherein The ultrasonic transducers include a plurality of ultrasonic transducers mounted on the side wall of the reactor shell and at least one ultrasonic transducer mounted on the bottom of the reactor shell.

4. The tank reactor according to claim 3, wherein The ultrasonic transducer installed on the upper part of the side wall of the reactor shell is inclined at 20° to 45° with respect to the horizontal direction toward the heat exchanger.

5. The tank reactor according to claim 3, wherein: The ultrasonic transducer installed at the bottom of the reactor shell is inclined at 40° to 90° with respect to the horizontal direction toward the heat exchanger.

6. The tank reactor according to claim 1, wherein The radius of the ultrasonic transducer is 15-80 mm.

7. The tank reactor according to claim 1, wherein The frequency of the ultrasonic transducer is 20-60 kHz.

8. The tank reactor according to claim 1, wherein The power density of the ultrasonic transducer is 30-50 W / cm 2 .

9. The tank reactor according to claim 1, wherein The tank reactor also includes a control unit and a monitor; The monitor monitors and adjusts in real time: the temperature, flow rate and pressure of the heat exchange fluid in the heat exchanger, the feed temperature, flow rate and pressure of the reactor, the discharge temperature, flow rate and pressure of the reactor, and the temperature, flow rate and pressure of the reflux material in the reactor; The monitor transmits the real-time monitoring data to the control unit, and the control unit processes the received data signal to obtain the real-time corrected scale thermal resistance R (m) , and correct the scale thermal resistance R in real time (m) Real-time feedback instructs the monitor to adjust various parameters; When the kettle reactor starts working, part of the ultrasonic transducers are turned on, and the rest are kept as standby; The specific feedback instruction process includes: When the control unit processes the obtained real-time corrected scale thermal resistance R (m) When the value is 10-15, it is considered that a small amount of scale is generated in the heat exchanger, which is determined to be level one. The monitor will be fed back in real time to instruct the feed flow rate of the reactor to decrease by 5%-10%, and the power of the ultrasonic transducer will be increased by 10%-20%; When the control unit processes the obtained real-time corrected scale thermal resistance R (m) When the value is 16-20, it is considered that the heat exchanger has a moderate amount of scale, which is determined to be level 2. The monitor will be fed back in real time to instruct the reactor to reduce the feed flow rate by 10%-30%, and increase the power of the ultrasonic transducer by 20%-40%. When the control unit processes the obtained real-time corrected scale thermal resistance R (m) When the value is ≥21, it is considered that the heat exchanger has a lot of scale, which is determined to be level 3. The monitor will be fed back in real time to instruct the reactor to reduce the feed flow rate by 30% to 50%, increase the power of the ultrasonic transducer by 20% to 40%, and enable the standby ultrasonic transducer to improve the descaling ability. The real-time corrected scale thermal resistance R (m) The calculation process is as follows: Where m is the correction coefficient, m is 1.706×10 11 ; r is the fouling thermal resistance on the tube side, in m 2 K / W; t is time, in seconds; Where α is the calculation constant in Albert Panchel's formula, which is 8.39m 2 ·K / (W·s); k is the calibration constant, k is 3.01×10 6 ; Re is the Reynolds number of the stirring blade. The Reynolds number physically represents the ratio of the inertial force to the viscous force level; E is the energy coefficient in Albert Panchel's formula, which is taken as 68 kJ / mol; R is the gas constant, which is 8.314×10 -3 kJ / mol; T f is the liquid film temperature, in K, and is the discharge temperature of the monitored reactor; γ is the calculation constant in Albert Panchel's formula, which is 4.03×10 -11 kJ / mol; τ is the shear force on the dirt surface, in Pa; Where ρ is the density of the reaction fluid, in kg / m 3 ; d j is the impeller diameter of the stirring paddle, in m; n is the impeller speed of the stirring paddle, in r / s, obtained by the set stirring rate of the stirring paddle; μ is the kinematic viscosity of the reaction fluid, in Pa·s; τ=(f / 2)ρv 2 Where ρ is the density of the reaction fluid, in kg / m 3 ; v is the speed at which the stirring paddle drives the reaction fluid, in m / s; v=πd j n f is the friction coefficient, f = 0.0791 / Re 0.25 .

10. The tank reactor according to claim 9, wherein The monitors include: a feed monitor, a discharge monitor, a reflux material monitor, a heat exchanger inlet monitor and a heat exchanger outlet monitor.

11. The tank reactor according to claim 10, wherein The monitor further comprises a product monitor and a stirring monitor; the feed monitor comprises a first feed monitor and a second feed monitor.

12. The tank reactor according to claim 9, wherein The control unit monitors the change of the resonant frequency of the ultrasonic transducer in real time, and adjusts the output frequency of the ultrasonic transducer in real time.

13. The tank reactor according to claim 9, wherein The control unit further comprises a display module, and the display module is used to display the parameters received by the control unit and the state of the control unit.

14. Use of the autoclave reactor with online polymer removal function according to any one of claims 1 to 13 in a process for synthesizing 1-butene and / or 1-octene by oligomerization of ethylene.

Images