Solid-liquid separation device and solid-liquid separation method for ethylene and acrylate monomer polymer

Abstract

The invention provides an ethylene and acrylate monomer polymer solid-liquid separation device, which comprises: a housing, which is a closed hollow entity; a liquid discharging pipe is arranged at the upper part of the shell, and a feeding pipe and a solid discharging pipe are arranged at the lower part of the shell; the filtering device is arranged in the shell, the liquid discharging pipe is located above the filtering device, the feeding pipe and the solid discharging pipe are located below the filtering device, and the solid-liquid separation device is defined by the filtering device and the shell into a settling area, a filtering area and a clear liquid collecting area. The motion trail of the reactant solution passing through the filtering device is from bottom to top; wherein the filtering device comprises one or more groups of filtering assemblies with a heat exchange function. The solid-liquid separation device is suitable for separation of ethylene and acrylate monomer polymers obtained through coordination copolymerization under a low-pressure condition.

Description

Technical Field

[0001] The invention relates to the technical field of solid-liquid separation equipment, and in particular to a solid-liquid separation device and a separation method for ethylene and acrylic acid ester monomer polymers. Background Art

[0002] The coordination polymerization technology using late transition metal catalysts can achieve polymerization of ethylene and acrylic ester monomers under mild conditions of ≤10MPa and ≤150℃, which has the advantage that the product structure can be adjusted as needed; however, due to its unique reaction characteristics, polymers with branched structures may be produced during the polymerization process, and since the polymer molecular chain contains ester groups, the polymer is prone to agglomeration or aggregation; when the concentration of acrylic ester monomers (such as methyl acrylate) in the reaction system is high, the ester content in the obtained product is also increased accordingly, and under the reaction conditions, the reaction system as a whole may be in a relatively viscous state; in addition, in some cases, a portion of acrylate monomers with a molecular weight of less than 1×10 3 g / mol polymer; under low-activity reaction conditions, the residual amount of solid impurities such as catalysts will be high. These factors cause the resulting polymer-containing reaction system to present a more complex morphology.

[0003] Since the morphology of the polymers obtained under different conditions may vary greatly, the viscosity, density and other properties of the reaction liquid also vary in a wide range, requiring that the reaction liquids with different properties be treated in the same separation equipment as much as possible; these factors put forward special requirements for the solid-liquid separation of the reaction liquid containing ethylene and acrylic ester monomer polymers obtained by coordination polymerization. In the prior art, solving the solid-liquid separation problem on-site in the reactor will make the reactor structure more complicated and may cause unnecessary interference to the polymerization reaction; using a filter alone for solid-liquid separation requires frequent switching and the need to solve the problem of easy clogging of the filter; using sedimentation for solid-liquid separation is time-consuming and inefficient; using extraction separation requires a large amount of extractant, increases the processing capacity of the post-processing process, and requires a larger equipment space; using centrifugation and other technologies for solid-liquid separation, in addition to requiring special equipment, also has the problem of high energy consumption.

[0004] Therefore, how to effectively separate the ethylene and acrylic ester monomer polymers and the reactant liquid is a technical problem that needs to be solved to realize its industrial application. Summary of the invention

[0005] In view of the above-mentioned deficiencies in the prior art, the present invention provides a solid-liquid separation device and a separation method for ethylene and acrylate monomer polymers. The solid-liquid separation device is suitable for separating ethylene and acrylate monomer polymers obtained by coordination copolymerization under low pressure conditions.

[0006] In order to achieve the above object, the present invention provides a solid-liquid separation device for ethylene and acrylic acid ester monomer polymers, the solid-liquid separation device comprising:

[0007] A shell, wherein the shell is a closed hollow entity;

[0008] The upper part of the shell is provided with a liquid discharge pipe, and the lower part of the shell is provided with a feed pipe and a solid discharge pipe;

[0009] A filter device, wherein the filter device is arranged in the housing, the liquid discharge pipe is located above the filter device, the feed pipe and the solid discharge pipe are located below the filter device, the filter device and the housing enclose the solid-liquid separation device into a sedimentation area, a filtration area and a clear liquid collection area, and the movement trajectory of the reactant solution passing through the filter device is from bottom to top;

[0010] Wherein, the filtering device includes one or more filtering components with heat exchange function.

[0011] In some embodiments, the filtering device includes two sets of filtering components with heat exchange function, namely a primary filtering component directly in contact with the reactant solution, and a secondary filtering component directly in contact with the liquid mixture obtained after filtering by the primary filtering component.

[0012] In some embodiments, the filtering device includes three groups of filtering components with heat exchange function, namely a primary filtering component directly in contact with the reactant solution, a secondary filtering component directly in contact with the liquid mixture obtained after filtration by the primary filtering component, and a tertiary filtering component in contact with the liquid output.

[0013] In some embodiments, the primary filter component or the secondary filter component includes a frame and a filter net attached to the frame.

[0014] In some of the embodiments, the skeleton includes a group of independent pipe networks with heat exchange function, and the pipe network is a pipe network that allows cold medium fluid and hot medium fluid to flow alternately as needed.

[0015] In some embodiments, the skeleton includes two independent groups of pipe networks with heat exchange function, one group of pipe networks is a cold medium pipe network that allows cold medium fluid to flow inside, and the other group of pipe networks is a hot medium pipe network that allows hot medium fluid to flow inside.

[0016] In some embodiments, the solid-liquid separation device further includes a stirring device, the stirring device extends into the sedimentation zone, the stirring device includes a stirring shaft, a stirring paddle and a first driving device, one end of the stirring shaft passes through the housing and is connected to the first driving device, and the other end is connected to the stirring paddle, and the stirring paddle is a composite paddle composed of a bottom paddle, a first-stage paddle and a second-stage paddle;

[0017] The liquid discharge pipe is connected to a second driving device for providing power for outputting the separated liquid to the outside of the shell. The second driving device is located inside or outside the shell.

[0018] In some embodiments, the liquid discharge pipe includes a pipe mouth, a pipe network and a pipe body, the pipe mouth adopts a specific lower baffle and upper suction structure, the pipe mouth is composed of a pipe mouth baffle, a pipe mouth filter and a suction port, the pipe mouth filter is located on the inner side of the pipe mouth baffle, and the pipe mouth baffle is a straight baffle, a U-shaped baffle or a V-shaped baffle;

[0019] Or the pipe mouth of the liquid discharge pipe is in the form of moving up and down, and the liquid discharge pipe located in the shell adopts a retractable hose, which is fixed on a retractable frame with a driving device and moves up and down with the movement of the retractable frame.

[0020] The present invention also provides a solid-liquid separation method for a polymer reaction liquid of ethylene and polyacrylate monomers, using the solid-liquid separation device as described above, comprising the following steps:

[0021] The reaction liquid containing ethylene and acrylic acid ester monomer polymer first enters the sedimentation zone through the feed port on the side wall or the bottom of the shell, where the initial solid-liquid separation is completed by sedimentation. The separated solid naturally sinks to the bottom area of ​​the shell due to gravity, and the liquid is located on the solid layer. As time goes by, a clear boundary between the solid layer and the liquid layer will be formed;

[0022] The filtration zone is located in the liquid layer, and then the separation of solids and liquids is completed through the filtration device located in the filtration zone, and clear liquid and solids are obtained after separation. The clear liquid is sent out of the shell through the discharge pipe located at the top of the shell, and the solid sinks to the bottom area of ​​the shell and is discharged from the solid discharge pipe.

[0023] As time goes by, a clear boundary between the solid layer and the liquid layer is formed, and the filter area is located in the liquid layer. The first separation of solid and liquid is completed by the primary filter component located in the filter area, and the solids such as polymers remaining in the liquid obtained after the preliminary solid-liquid separation are further removed to obtain a clear liquid.

[0024] The clear liquid passes through the secondary filter assembly located in the middle of the shell to complete the second separation of solids and liquids. The clear liquid that completes the secondary solid-liquid separation is sent out of the shell through the discharge pipe located at the top of the shell. A tertiary filter assembly is provided at the discharge pipe to remove the residual solids in the clear liquid again.

[0025] The clear liquid is sent out of the shell through the discharge pipe located at the top of the shell, and the solid sinks to the bottom area of ​​the shell and is discharged through the solid discharge pipe.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] The present invention adopts a separation method in which the reactant solution enters from the bottom and exits from the filtering facility in the solid-liquid separation device. The density of solids such as polymers is greater than that of liquids such as solvents, and they are easy to settle to the bottom of the solid-liquid separation device under the action of gravity, thereby greatly reducing the adhesion of solids such as polymers in the reaction liquid to the filtering component, effectively solving the problem that the traditional top-in and bottom-out method or side-in and side-out method is prone to clogging of the filtering facility. Compared with the top-in and bottom-out method, the clogging rate of the filtering component is reduced by 90%.

[0028] The present invention utilizes the property that the morphology of the polymer obtained by coordination polymerization can change with the change of temperature. By setting a filtering facility with a special structure having a heat exchange function, cold and hot media are alternately passed through the filtering facility with a special structure having a heat exchange function, so that the polymer solids contained in the reactant solution are quickly precipitated around the pipe network or quickly fall off the pipe network, and the polymer and other solids in the reaction solution are condensed and agglomerated to the maximum extent. Compared with the simple sedimentation method, the filtration efficiency is increased by 100 times. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0030] Figure 1 The structure of the solid-liquid separation device of ethylene and acrylic acid ester monomer polymer shown in the embodiment of the present invention is schematically shown. Figure 1 (having a set of filtering components);

[0031] Figure 2 The structure of the solid-liquid separation device of ethylene and acrylic acid ester monomer polymer shown in the embodiment of the present invention is schematically shown. Figure 2 (with two sets of filtering components);

[0032] Figure 3 The structure of the filter assembly shown in the embodiment of the present invention is schematically shown in FIG. Figure 1 (separate pipe network);

[0033] Figure 4 The structure of the filter assembly shown in the embodiment of the present invention is schematically shown in FIG. Figure 2 (two sets of pipe networks);

[0034] Figure 5 The solid-liquid separation device provided with a stirring device as shown in the embodiment of the present invention;

[0035] Figure 6 It is a schematic cross-sectional view of the liquid discharge pipe structure shown in an embodiment of the present invention;

[0036] in:

[0037] 1- housing;

[0038] 101-settlement area;

[0039] 102- filtration area;

[0040] 103- clear liquid collection area;

[0041] 2-Liquid discharge pipe;

[0042] 201-pipe opening;

[0043] 202-pipeline network;

[0044] 203-tube body;

[0045] 3-feeding pipe;

[0046] 4-Solid discharge pipe;

[0047] 5- Filter device;

[0048] 51- Filter component;

[0049] 501- primary filter component;

[0050] 502-secondary filter assembly;

[0051] 5011-skeleton;

[0052] 5012-filter;

[0053] 50111-Pipeline network with heat exchange function;

[0054] 50112-cold medium pipe network;

[0055] 50113-heat medium pipe network;

[0056] 6-Stirring device. DETAILED DESCRIPTION

[0057] The technical solution of the present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments to further understand the purpose, solution and effect of the present invention, but it is not intended to limit the scope of protection of the claims attached to the present invention.

[0058] Certain words are used in the specification and subsequent claims to refer to specific components or parts. It should be understood by those of ordinary skill in the art that technical users or manufacturers may refer to the same component or part by different nouns or terms. This specification and subsequent claims do not use differences in names as a way to distinguish components or parts, but use differences in the functions of components or parts as the criteria for distinction. "Including" and "comprising" mentioned throughout the specification and subsequent claims are open-ended terms and should be interpreted as "including but not limited to". In addition, the word "connect" here includes any direct and indirect electrical connection means. Indirect electrical connection means include connection through other devices.

[0059] It should be noted that, in the description of the present invention, the terms "lateral", "longitudinal", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and "about", or "approximately", "substantially", "left and right" and the like indicating directions or positional relationships or parameters are all based on the directions or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description content, and do not indicate or imply that the referred device or element must have a specific direction, specific size, or be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0060] Under the mild conditions of ≤100℃ and ≤10MPa, ethylene is used as raw material, acrylate compounds are used as copolymers, and late transition metal catalysts and slurry processes are used to obtain ethylene and acrylate monomer polymers through coordination polymerization. The reaction liquid is a complex gas-liquid-solid three-phase system, containing about 20% ethylene, about 70% solvent and unreacted acrylate monomers, about 10% polymer products and solid impurities such as residual catalysts. After the polymerization reaction is completed, the reaction liquid is separated, and the following technical problems need to be solved: During the separation process, the solid-liquid separation of the polymer solid and the reaction liquid needs to be solved at the same time, There are two problems: the gas-liquid separation of unreacted ethylene and the reaction liquid, in order to minimize the loss of unreacted raw materials and solvents and reduce production costs; compared with high-pressure free radical polymerization, the advantage of coordination polymerization is that the structure of the polymer product can be regulated as needed. Therefore, the morphology of the polymer obtained under different conditions may vary greatly, and the viscosity, density and other properties of the reaction liquid also vary over a wider range. It is required to complete the treatment of reaction liquids with different properties in the same separation equipment as much as possible; these factors put forward special requirements for the solid-liquid separation of the reaction liquid containing ethylene and acrylate monomer polymers obtained by coordination polymerization.

[0061] In the prior art, solving the solid-liquid separation problem on-site in the reactor will make the structure of the reactor more complicated and may cause unnecessary interference to the polymerization reaction; using a filter alone for solid-liquid separation requires frequent switching and solves the problem of easy clogging of the filter; using sedimentation to separate solid and liquid is time-consuming and inefficient; using extraction separation requires consuming a large amount of extractant, increasing the processing capacity of the post-processing process and requiring a larger equipment space; using centrifugation and other technologies for solid-liquid separation, in addition to requiring special equipment, also has the problem of high energy consumption; for this reason, the present invention proposes the following special processing device capable of achieving solid-liquid separation of ethylene and acrylate monomer polymers based on the characteristics of the reaction liquid containing ethylene and acrylate monomer polymers obtained by coordination polymerization.

[0062] First, (1) the copolymerization method of ethylene and acrylic ester monomers is as follows: using alkyl salicylaldehyde imine late transition metal complex or alkyl diimine late transition metal complex as a catalyst precursor, using alkyl aluminum compound and / or organic boron compound as an activator, using at least one of toluene, hexane, etc. as a solvent, and completing the copolymerization of ethylene and acrylic ester monomers, especially the copolymerization of ethylene and methyl acrylate, under the conditions of 1.0-10.0 MPa, 30-100°C, and 0.5-8h. Replace the reactor with 0.1MPa nitrogen three times to exhaust the air in the reactor. Heat the reactor to 150°C under a vacuum of -0.1MPa, keep the temperature constant for 2h, and then cool to room temperature. Replace the reactor with 0.1MPa nitrogen three times again, and then pressurize the reactor with 0.1MPa ethylene to 0.1MPa, and replace it three times. At room temperature and in an ethylene atmosphere, the measured solid and liquid materials such as catalysts, solvents and polar monomers are added to the reactor through the liquid material feed port on the reactor cover, and the reactor filling coefficient is maintained at 0.6. Start the stirring paddle, and the reactor reaches the set reaction temperature through the heat medium in the jacket outside the reactor. The reaction temperature is controlled to be constant within the desired range by online adjusting the flow rate of the cold medium in the heat exchange tube in the reactor. The temperature is monitored by the temperature measuring facilities inside the reactor and the required signal of the temperature controller is fed back. The temperature control accuracy is ±1°C. Ethylene is introduced to make the reactor reach the set reaction pressure and keep the reactor pressure constant. The instantaneous consumption flow and cumulative consumption flow of ethylene are measured by a mass flowmeter. After the reaction reaches the set time, stop stirring, release the ethylene pressure until the pressure gauge shows 0MPa, and obtain a reaction liquid containing ethylene and acrylic ester monomer polymers.

[0063] Source of raw materials and equipment: Ethylene, polymerization grade, purity 99.9%, produced by Daqing Branch of China National Petroleum Corporation.

[0064] Methyl acrylate, analytical grade, 98.5%, containing 0.05% MEHQ stabilizer, provided by Shanghai Aladdin Biochemical Technology Co., Ltd.

[0065] Methyl methacrylate, analytical grade, 98.5%, containing 0.05% MEHQ stabilizer, provided by Shanghai Aladdin Biochemical Technology Co., Ltd.

[0066] Toluene solution of methylaluminoxane, concentration 10%, provided by Huainan Kedi Chemical Technology Co., Ltd.

[0067] Toluene, analytical grade, 99.5%, was provided by Nanjing Chemical Reagent Co., Ltd.

[0068] Hexane, 98%, provided by Fushun Branch of PetroChina Co., Ltd.

[0069] Secondly, (2) the solid-liquid separation efficiency is calculated using the following method:

[0070] Separation efficiency = M 固 / (M 固 +(M 液后 -M 液前 ))(Formula I)

[0071] Where M 固 is the total mass of the dried solid obtained after solid-liquid separation, M 液后 -M 液前 is the mass difference of the liquid before and after separation, where M 液前 Calculated by the following formula:

[0072] M 液前 =M 总 -M 固 (Formula II)

[0073] Further, see Figure 1 An embodiment of the present invention provides a solid-liquid separation device for ethylene and acrylic acid ester monomer polymers, the solid-liquid separation device comprising: a shell 1, the shell 1 is a hollow entity formed by an upper and a lower head; the upper head is provided with a liquid discharge pipe 2, the lower head is provided with a feed pipe 3 and a solid discharge pipe 4; a filter device 5, the filter device 5 is arranged in the shell 1, the liquid discharge pipe 2 is located above the filter device 5, the feed pipe 3 and the solid discharge pipe 4 are located below the filter device 5, the filter device 5 and the shell 1 enclose the solid-liquid separation device into a sedimentation area 101, a filtration area 102 and a clear liquid collection area 103, and the movement trajectory of the reactant solution passing through the filter device 5 is from bottom to top; wherein, the filter device 5 includes a group of filter components 51 with heat exchange function.

[0074] In the embodiment of the present invention, the reactant solution containing solids such as polymers adopts a bottom-in-top-out separation process, the feed inlet of the reactant solution containing solids such as polymers is located below the filter component 51, the liquid discharge pipe 2 is located above the filter component 51, and the movement trajectory of the liquid through the filter component 51 is from bottom to top, thereby forming an actual polymer solid sedimentation area in the shell 1 of the solid-liquid separation device, thereby maximizing the filtering effect of the filter component and eliminating the possibility of the filter component being blocked by polymer solids.

[0075] The shell 1 in this embodiment is a hollow solid formed by closing a suitable shape such as a cylinder and / or a cube and / or a cone. Considering the convenience of manufacturing and use, the shell of this embodiment is preferably a cylinder and / or a cube. It is worth noting that the shell in the embodiment of the present invention can be an independent sealed individual, or it can be composed of an upper shell and a lower shell. The upper shell and the lower shell are combined together by a sealing and connecting device and can be disassembled. In this embodiment, the shell body can also be provided with a plurality of gas feed ports, liquid feed ports, gas discharge ports, liquid discharge ports, pressure measuring ports, temperature measuring ports, cold medium feed ports, hot medium feed ports, cold medium discharge ports, hot medium discharge ports and other pipe ports designed as needed (such as observation holes, manholes) and other facilities connected to the outside, and the number is designed according to demand. The cold medium feed port, hot medium feed port, cold medium discharge port and hot medium discharge port are connected to the filter assembly; the observation hole is for convenient real-time monitoring of the status inside the equipment during the production process, and the manhole is used for the operator to enter the shell body under permitted conditions when necessary. The observation hole and the manhole are usually sealed and opened only when needed.

[0076] See also Figure 2 Another embodiment of the present invention discloses a solid-liquid separation device, which is similar to the aforementioned embodiment, except that the filtering device 5 includes two groups of filtering components with heat exchange functions, namely a primary filtering component 501 directly in contact with the reactant solution, and a secondary filtering component 502 directly in contact with the liquid mixture obtained after filtering by the primary filtering component 501.

[0077] Another embodiment of the present invention discloses a solid-liquid separation device, which is similar to the aforementioned embodiment, except that the filter device 5 includes three groups of filter components with heat exchange functions, namely a primary filter component 501 directly in contact with the reactant solution, a secondary filter component 502 directly in contact with the liquid mixture obtained after filtering by the primary filter component, and a tertiary filter component in contact with the liquid discharge; most of the polymer solids contained in the reactant solution are retained in the sedimentation zone of the solid-liquid separation device by the primary filter component 501, and the polymer solids that cannot be retained by the primary filter component 501 are further retained by the secondary filter component 502, thereby improving the filtering effect; the tertiary filter component prevents the residual polymer solids from mixing into the solvent sent out of the solid-liquid separation device.

[0078] It is worth noting that the filter device in the solid-liquid separation device disclosed in the embodiment of the present invention is not limited to including one, two or three groups of filter components with heat exchange function, but can also be more groups of filter components with heat exchange function, which can be flexibly configured as needed. Each level of filter components maintains a necessary spacing, for example, not more than 10 cm.

[0079] See also Figure 3 and Figure 4 In the embodiment of the present invention, the primary filter assembly 501 or the secondary filter assembly 502 includes a skeleton 5011 and a filter net 5012 attached to the skeleton 5011, and the filter net 5012 is fixed to the pipe network skeleton 5011 and can be easily disassembled; the pipe network can be in any feasible combination, such as cross, diamond cross, parallel, superimposed, alternately arranged, etc. In the embodiment of the present invention, the skeleton 5011 includes a group of independent pipe networks 50111 with heat exchange function, and the pipe network is a pipe network that allows cold medium fluid and hot medium fluid to flow alternately as needed. It is worth noting that the skeleton in the embodiment of the present invention is not limited to including a group of independent pipe networks 50111 with heat exchange function, and can also include two groups of independent pipe networks with heat exchange function, one group of pipe networks is a cold medium pipe network 50112 that allows cold medium fluid to flow, and the other group of pipe networks is a hot medium pipe network 50113 that allows hot medium fluid to flow. Two sets of pipe networks are more flexible and convenient to use than one set of pipe networks. The heat exchange function can promote the polymer solids contained in the reactant solution to quickly settle around the pipe network or quickly fall off the pipe network, further improving the efficiency of separating the polymer solids contained in the reactant solution from the solution.

[0080] In the embodiments of the present invention, the property that the morphology of the polymer obtained by coordination polymerization can change with the change of temperature is utilized. By alternately passing cold and hot media through the heat exchange facility, the polymer solids contained in the reactant solution are caused to quickly settle around the pipe network or quickly fall off the pipe network, and the polymer and other solids in the reaction solution are condensed in the sedimentation area to the maximum extent, thereby reducing the load of the filter component and further improving the efficiency of separating the polymer and other solids from the solution.

[0081] See also Figure 5 Another embodiment of the present invention provides a solid-liquid separation device, which is similar to the solid-liquid separation device disclosed in the above embodiment, except that the solid-liquid separation device in this embodiment further includes a stirring device 6, which extends into the sedimentation zone 101, and includes a stirring shaft, a stirring paddle and a first driving device. One end of the stirring shaft passes through the shell and is connected to the first driving device, and the other end is connected to the stirring paddle. The stirring paddle is a composite paddle composed of a bottom paddle, a first-stage paddle and a second-stage paddle. The first driving device is fixed to the outside of the shell as a part of the solid-liquid separation device of the present invention, and the stirring paddle is located in the shell. The paddles of the stirring paddle are arranged at equal intervals along the stirring shaft and are evenly distributed around the circumference. The function of the stirring device is to quickly mix the separation aid (such as a precipitant) and the reaction liquid containing the polymer solid by adding a separation aid, so as to promote the rapid separation of the solid and the liquid, achieve the effect of rapid mixing, and improve the mixing efficiency.

[0082] The liquid discharge pipe 2 described in the embodiment of the present invention is connected to the second driving device, which is used to provide power for outputting the separated liquid to the outside of the shell. The second driving device is located inside or outside the shell. When the driving facility is located inside the shell, a submersible pump or the like can be used to provide liquid output power; when the driving facility is located outside the shell, a negative pressure device or the like can be used to provide liquid output power; in the embodiment of the present invention, it is particularly recommended to use a negative pressure device (such as a vacuum pump) outside the shell to form a pressure difference in the sedimentation area, filtration area and clear liquid area inside the shell to achieve the purpose of quickly separating solids and liquids.

[0083] See also Figure 6 In the embodiment of the present invention, the liquid discharge pipe 2 includes a pipe mouth 201, a pipe network 202 and a pipe body 203. The pipe mouth 201 adopts a specific lower baffle and upper suction structure. The pipe mouth 201 is composed of a pipe mouth baffle, a pipe mouth filter and a suction port. The pipe mouth filter is located on the inner side of the pipe mouth baffle. The pipe mouth baffle is a straight baffle, a U-shaped baffle or a V-shaped baffle, which can effectively prevent solids such as polymers in the liquid from entering the pipe mouth from the bottom direction of the liquid discharge pipe. The pipe mouth filter is located on the inner side of the pipe mouth baffle, which can further effectively prevent solids such as polymers in the liquid from entering the pipe mouth, thereby further improving the filtering effect of polymer solids.

[0084] Or the pipe mouth 201 of the liquid discharge pipe is in the form of moving up and down, and the liquid discharge pipe located in the shell adopts a retractable hose, which is fixed on a retractable frame with a driving device and moves up and down with the movement of the retractable frame, thereby further improving the discharge quality and efficiency of the liquid.

[0085] Another embodiment of the present invention provides a solid-liquid separation method for a polymer reaction liquid of ethylene and polyacrylate monomers, using the solid-liquid separation device as described above, comprising the following steps:

[0086] The reaction liquid containing ethylene and acrylic acid ester monomer polymer first enters the sedimentation zone 101 through the feed port on the side wall or the bottom of the shell, where the initial solid-liquid separation is completed by sedimentation. The separated solid naturally sinks to the bottom area of ​​the shell due to gravity, and the liquid is located on the solid layer. As time goes by, a clear boundary between the solid layer and the liquid layer will be formed;

[0087] The filter area 102 is located in the liquid layer, and then the separation of solids and liquids is completed by the filter device 5 located in the filter area 102, and clear liquid and solids are obtained after separation. The clear liquid is sent out of the shell through the discharge pipe 2 located at the top of the shell, and the solid sinks to the bottom area of ​​the shell and is discharged by the solid discharge pipe 4.

[0088] As time goes by, a clear boundary between the solid layer and the liquid layer is formed, and the filter area 102 is located in the liquid layer. The first separation of solid and liquid is completed by the primary filter component 501 located in the filter area 102, and the solids such as polymers remaining in the liquid obtained after the preliminary solid-liquid separation are further removed to obtain a clear liquid.

[0089] The clear liquid passes through the secondary filter assembly 502 located in the middle of the shell to complete the second separation of solid and liquid. The clear liquid that completes the secondary solid-liquid separation is sent out of the shell through the discharge pipe located at the top of the shell. A tertiary filter assembly is provided at the discharge pipe to remove the residual solids in the clear liquid again.

[0090] The clear liquid is sent out of the shell 1 through the discharge pipe 2 located at the top of the shell, and the solids sink to the bottom area of ​​the shell and are discharged through the solid discharge pipe.

[0091] More specifically, the solid-liquid separation process of the reaction liquid containing ethylene and acrylic ester monomer polymers is completed by using the solid-liquid separation device disclosed in the embodiment of the present invention as follows: the reaction liquid containing ethylene and acrylic ester monomer polymers first enters the shell through the feed pipe, and a cold fluid medium (such as water) with a temperature of ≤20°C is passed into the filter component to allow the reaction liquid to naturally settle for ≥1 hour. The material condition in the shell is observed from the observation hole. When the liquid above the filter component is clear and transparent, or a liquid sample is taken from the observation hole to observe outside the shell and no turbidity is observed, the vacuum pump system connected to the liquid discharge pipe is started to guide the liquid above the filter component out of the shell; the residual liquid in the shell can be discharged out of the shell through the solid discharge pipe; the cold fluid medium in the pipe network is guided out, and then a hot fluid medium is passed into the pipe network to further remove the residual liquid contained in the solids such as the polymer attached to the filter component, and the solids fall off from the filter component in the form of powder or particles, and are discharged from the shell from the solid discharge port at the bottom of the shell.

[0092] In the embodiment of the present invention, a negative pressure facility connected to the clear liquid discharge pipe forms an actual pressure difference in the shell to accelerate the separation of solid and liquid. A heat exchange facility is provided in the sedimentation area to promote the rapid aggregation or rapid shedding of solids such as polymers in the bottom sedimentation area centered on the heat exchange facility. The solids such as polymers obtained after sedimentation and filtration are discharged from the shell in the form of powder or particles through the heating and drying effect of the heat exchange facility. An independent filtering facility is provided at the bottom of the sedimentation area to thoroughly remove the residual liquid in the solid layer.

[0093] By using the solid-liquid separation device containing ethylene and acrylic acid ester monomers obtained by coordination polymerization disclosed in the above embodiments of the present invention, the separation efficiency of polymer solids reaches 99%.

[0094] The above description is only a preferred embodiment of the present invention and does not limit the present invention in other forms. Any technician familiar with the profession may use the technical content disclosed above to change or modify it into an equivalent embodiment with equivalent changes and apply it to other fields. However, any simple modification, equivalent change and modification made to the above embodiment based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A solid-liquid separation device for ethylene and acrylic acid ester monomer polymers, characterized in that: The solid-liquid separation device comprises: A shell, wherein the shell is a closed hollow entity; The upper part of the shell is provided with a liquid discharge pipe, and the lower part of the shell is provided with a feed pipe and a solid discharge pipe; A filter device, wherein the filter device is arranged in the housing, the liquid discharge pipe is located above the filter device, the feed pipe and the solid discharge pipe are located below the filter device, the filter device and the housing enclose the solid-liquid separation device into a sedimentation area, a filtration area and a clear liquid collection area, and the movement trajectory of the reactant solution passing through the filter device is from bottom to top; Wherein, the filtering device includes one or more filtering components with heat exchange function.

2. The solid-liquid separation device for ethylene and acrylic acid ester monomer polymer according to claim 1, characterized in that: The filtering device comprises two groups of filtering components with heat exchange function, namely a primary filtering component directly in contact with the reactant solution, and a secondary filtering component directly in contact with the liquid mixture obtained after filtering by the primary filtering component.

3. The solid-liquid separation device for ethylene and acrylic acid ester monomer polymer according to claim 1, characterized in that: The filtering device includes three groups of filtering components with heat exchange function, namely a primary filtering component directly in contact with the reactant solution, a secondary filtering component directly in contact with the liquid mixture obtained after filtration by the primary filtering component, and a tertiary filtering component in contact with the liquid output.

4. The solid-liquid separation device for ethylene and acrylic acid ester monomer polymer according to claim 2 or 3, characterized in that: The primary filter component or the secondary filter component comprises a frame and a filter net attached to the frame.

5. The solid-liquid separation device for ethylene and acrylic acid ester monomer polymer according to claim 4, characterized in that: The skeleton includes a group of independent pipe networks with heat exchange function, and the pipe network is a pipe network that allows cold medium fluid and hot medium fluid to flow alternately as needed.

6. The solid-liquid separation device for ethylene and acrylic acid ester monomer polymer according to claim 4, characterized in that: The skeleton includes two independent groups of pipe networks with heat exchange functions, one group of pipe networks is a cold medium pipe network that allows cold medium fluid to flow inside, and the other group of pipe networks is a hot medium pipe network that allows hot medium fluid to flow inside.

7. The solid-liquid separation device for ethylene and acrylic acid ester monomer polymer according to claim 1, characterized in that: The solid-liquid separation device also includes a stirring device, which extends into the sedimentation zone. The stirring device includes a stirring shaft, a stirring paddle and a first driving device. One end of the stirring shaft passes through the housing and is connected to the first driving device, and the other end is connected to the stirring paddle. The stirring paddle is a composite paddle composed of a bottom paddle, a first-stage paddle and a second-stage paddle. The liquid discharge pipe is connected to a second driving device for providing power for outputting the separated liquid to the outside of the shell. The second driving device is located inside or outside the shell.

8. The solid-liquid separation device for ethylene and acrylic acid ester monomer polymer according to claim 1, characterized in that: The liquid discharge pipe comprises a pipe mouth, a pipe network and a pipe body, wherein the pipe mouth adopts a specific lower baffle and upper suction structure, and the pipe mouth is composed of a pipe mouth baffle, a pipe mouth filter and a suction port, wherein the pipe mouth filter is located on the inner side of the pipe mouth baffle, and the pipe mouth baffle is a straight baffle, a U-shaped baffle or a V-shaped baffle; Or the pipe mouth of the liquid discharge pipe is in the form of moving up and down, and the liquid discharge pipe located in the shell adopts a retractable hose, which is fixed on a retractable frame with a driving device and moves up and down with the movement of the retractable frame.

9. A method for solid-liquid separation of a polymer reaction liquid of ethylene and polyacrylate monomers, using the solid-liquid separation device according to any one of claims 1 to 8, characterized in that: The steps include: The reaction liquid containing ethylene and acrylic acid ester monomer polymer first enters the sedimentation zone through the feed port on the side wall or the bottom of the shell, where the initial solid-liquid separation is completed by sedimentation. The separated solid naturally sinks to the bottom area of ​​the shell due to gravity, and the liquid is located on the solid layer. As time goes by, a clear boundary between the solid layer and the liquid layer will be formed; The filtration zone is located in the liquid layer, and then the separation of solids and liquids is completed through the filtration device located in the filtration zone, and clear liquid and solids are obtained after separation. The clear liquid is sent out of the shell through the discharge pipe located at the top of the shell, and the solid sinks to the bottom area of ​​the shell and is discharged from the solid discharge pipe.

10. The solid-liquid separation method according to claim 9, characterized in that: As time goes by, a clear boundary between the solid layer and the liquid layer is formed. The filter area is located in the liquid layer. The first separation of solid and liquid is completed by the primary filter component located in the filter area, and the solids such as polymers remaining in the liquid obtained after the initial solid-liquid separation are further removed to obtain a clear liquid. The clear liquid passes through the secondary filter assembly located in the middle of the shell to complete the second separation of solids and liquids. The clear liquid that completes the secondary solid-liquid separation is sent out of the shell through the discharge pipe located at the top of the shell. A tertiary filter assembly is provided at the discharge pipe to remove the residual solids in the clear liquid again. The clear liquid is sent out of the shell through the discharge pipe located at the top of the shell, and the solid sinks to the bottom area of ​​the shell and is discharged through the solid discharge pipe.

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