Temperature control system of prepolymerization reaction kettle of HIPS (High Impact Polystyrene) production line

Abstract

The utility model relates to the technical field of HIPS (High Impact Polystyrene) production lines, in particular to a temperature control system of a prepolymerization reaction kettle of an HIPS production line, which comprises a glue solution preheater, a prepolymerization reaction kettle and a temperature control loop, the glue solution preheater is electrically connected with the temperature control loop, the glue solution preheater is used for heating glue solution to enter the prepolymerization reaction kettle, and the temperature control loop is electrically connected with the glue solution preheater. And the temperature control loop is used for controlling the working state of the glue solution preheater so as to keep the glue solution in the prepolymerization reaction kettle in a constant-temperature state. According to the utility model, the glue solution preheater, the pre-polymerization reaction kettle and the temperature control loop are matched, so that the pre-polymerization reaction temperature in the HIPS production process can be well controlled within the range required by the production technology, and the polymerization system in the pre-polymerization reaction kettle can be ensured to meet the purpose of well grafting polystyrene with rubber; and the high-quality high impact polystyrene HIPS product is obtained.

Description

Technical Field

[0001] The utility model relates to the technical field of a HIPS production line, in particular to a temperature control system of a prepolymerization reaction kettle of a HIPS production line. Background Art

[0002] HIPS (High Impact Polystyrene) is a plastic material with high impact strength and good impact resistance. Compared with traditional polystyrene (PS), HIPS has better mechanical properties and processing properties.

[0003] The production process of HIPS mainly includes the following steps:

[0004] Raw material preparation: First, you need to prepare the raw materials needed to produce HIPS, including styrene monomer, rubber modifier, impact agent and other auxiliary additives.

[0005] Pretreatment: Pretreatment of raw materials, including purification, drying and other operations, to ensure the quality and stability of raw materials.

[0006] Polymerization reaction: Add the treated styrene monomer and rubber modifier into the polymerization reactor (reactor) in a certain proportion, and carry out free radical polymerization under the action of the initiator to generate polystyrene. At the same time, the rubber modifier will also be dispersed in the polystyrene matrix during the polymerization reaction to form a sea-island structure blend.

[0007] Devolatilization treatment: After the polymerization reaction is completed, devolatilization treatment is required to remove unreacted monomers and low molecular weight volatiles to obtain high-quality HIPS products.

[0008] Processing and molding: The HIPS after devolatilization is processed and molded, such as extrusion granulation, injection molding, etc., to make the final HIPS product.

[0009] There is another step between the pretreatment and polymerization steps, which is the prepolymerization reaction. Pretreatment is to ensure the smooth progress of production, and the raw materials are purified and dried. Prepolymerization reaction is to add the treated styrene monomer and rubber modifier into the polymerization reactor in a certain proportion, and carry out free radical polymerization reaction under the action of initiator. Polymerization reaction is the process of converting the product of prepolymerization reaction into polystyrene.

[0010] Among them, the stable control of the prepolymerization temperature has a crucial impact on the quality and performance of HIPS products. Too high a temperature may lead to a decrease in the molecular weight of the polymer, while too low a temperature may lead to an increase in the molecular weight of the polymer or even the production of insoluble polymers. These will affect the performance and use of the final product. Therefore, it is necessary to adopt a reasonable control object and automatic control scheme to accurately control the temperature of the prepolymerization reaction. Utility Model Content

[0011] In view of the above problems, the utility model adopts reasonable control objects and automatic control schemes to accurately control the temperature of the prepolymerization reaction, and designs a temperature control system for the prepolymerization reactor of the HIPS production line.

[0012] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a temperature control system for a prepolymerization reactor of a HIPS production line, comprising a glue preheater, a prepolymerization reactor and a temperature control circuit, the glue preheater being electrically connected to the temperature control circuit, the glue preheater being used to heat the glue that is about to enter the prepolymerization reactor, and the temperature control circuit being used to control the working state of the glue preheater to keep the glue in the prepolymerization reactor at a constant temperature.

[0013] As a preferred embodiment of the utility model, the glue preheater includes a storage bin and a heater, the heater is arranged outside the storage bin, the storage bin is used to store the glue to be introduced into the prepolymerization reactor, and the heater is used to heat the glue in the storage bin.

[0014] As a preferred embodiment of the utility model, the storage bin is provided with a first feed port and a first discharge port, the prepolymerization reactor is provided with a second feed port and a second discharge port, and the first discharge port is sealed and connected to the second feed port via a pipeline.

[0015] As a preferred embodiment of the utility model, the heater is a heating oil pipe, the heating oil pipe is arranged outside the storage bin, and the two ends of the heating oil pipe are respectively an oil inlet and an oil outlet.

[0016] As a preferred embodiment of the utility model, the temperature control circuit includes a kettle temperature control main regulator and an oil temperature control sub-regulator. The kettle temperature control main regulator is used to detect the temperature in the prepolymerization reactor, and the oil temperature control sub-regulator is used to detect the temperature of the glue output by the glue preheater.

[0017] As a preferred embodiment of the utility model, the temperature control circuit includes a heating oil flow control valve, which is arranged at the oil inlet of the heating oil pipe, and the heating oil flow control valve is used to control the flow of the heating oil entering the heating oil pipe.

[0018] Compared with the prior art, the utility model has the following beneficial effects:

[0019] The utility model can well control the prepolymerization temperature in the HIPS production process within the range required by the production technology through the coordination among the glue liquid preheater, the prepolymerization reactor and the temperature control circuit, and can ensure that the polymerization system in the prepolymerization reactor can meet the purpose of good rubber grafting polystyrene, so as to obtain high-quality high-impact polystyrene HIPS products.

[0020] The utility model makes full use of the reaction heat of the polymerization reaction and the heat of the glue liquid itself through the cooperation between the glue liquid preheater, the prepolymerization reactor and the temperature control circuit, reduces energy consumption and cost, and also ensures the smooth progress of the grafting reaction and the stability of the product quality. Through precise temperature control, side reactions or product quality problems caused by excessively high or low temperatures can be avoided, thereby improving production efficiency and economic benefits.

[0021] Additional aspects and advantages of the present invention will be given in part in the following description, and in part will become apparent from the following description, or will be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0023] Figure 1 This is a schematic diagram of the temperature control system of the prepolymerization reactor of a HIPS production line. Figure 1 .

[0024] Figure 2 This is a schematic diagram of the temperature control system of the prepolymerization reactor of a HIPS production line. Figure 2 .

[0025] Reference numerals include:

[0026] Glue liquid preheater 1, storage bin 1a, first feed inlet 1a1, first discharge port 1a2, heater 1b, heating oil pipe 1b1, oil inlet 1b2, oil outlet 1b3, prepolymerization reactor 2, second feed inlet 2a, second discharge port 2b, temperature control circuit 3, reactor temperature control main regulator 3a, oil temperature control auxiliary regulator 3b, heating oil flow control valve 3c, glue liquid flow direction 4, heating oil flow direction 5, temperature control component connection relationship 6. DETAILED DESCRIPTION

[0027] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0028] Combination Figure 1As shown, the temperature control system of a prepolymerization reactor of a HIPS production line described in the utility model includes a glue preheater 1, a prepolymerization reactor 2 and a temperature control circuit 3, the glue preheater 1 is electrically connected to the temperature control circuit 3, the glue preheater 1 is used to heat the glue that is about to enter the prepolymerization reactor 2, the temperature control circuit 3 is used to control the working state of the glue preheater 1 to keep the glue in the prepolymerization reactor 2 in a constant temperature state, and the flow direction of the glue between the glue preheater 1 and the prepolymerization reactor 2 is shown in the glue flow direction 4.

[0029] Principle of the scheme: According to the characteristics of the material: the temperature of the rubber solution of polybutadiene should not be higher than 75 degrees, and the reaction temperature of the prepolymerization reactor 2 is controlled below 115 degrees; the styrene conversion rate of the prepolymerization reactor 2 is controlled at 12% to 13% and the reaction heat of styrene conversion to polystyrene is 163.6 kal / kg, and the specific heat of styrene, polystyrene and glue mixture is 0.43 kal / kg. According to this heat balance calculation, it is obtained that as long as the temperature of the glue / styrene is raised to 66.5 degrees, the reaction heat will raise the temperature of the material to 112 degrees. Therefore, by controlling the temperature of the glue entering the prepolymerization reactor 2, the temperature of the prepolymerization reactor 2 can reach the expected reaction temperature, the reaction temperature of the prepolymerization reactor 2 is the main adjustment, the glue temperature at the outlet of the glue preheater 1 is the secondary adjustment, and the heating temperature of the glue by the glue preheater 1 is controlled by the temperature control loop 3, so as to accurately control the reaction temperature of the prepolymerization reactor 2. The principle of the whole process is: the heat provided by the reaction heat of the polymerization reaction in the prepolymerization reactor 2 plus the heat of the glue liquid with a certain temperature, thereby maintaining the temperature of the prepolymerization reactor 2 within the temperature range required for the grafting reaction.

[0030] The utility model cooperates with the glue liquid preheater 1, the prepolymerization reactor 2 and the temperature control circuit 3, so that the prepolymerization reaction temperature in the HIPS production process can be well controlled within the range required by the production technology, and the polymerization system in the prepolymerization reactor can be guaranteed to meet the purpose of good rubber grafting polystyrene, so as to obtain high-quality high-impact polystyrene HIPS products.

[0031] Specifically, refer to Figure 2 As shown, the glue liquid preheater 1 includes a storage bin 1a and a heater 1b, wherein the heater 1b is arranged outside the storage bin 1a, and the storage bin 1a is used to store the glue liquid to be entered into the prepolymerization reactor 2, and the heater 1b is used to heat the glue liquid in the storage bin 1a. By heating the glue liquid in the storage bin 1a, the glue liquid will have a certain amount of heat when entering the prepolymerization reactor 2, and then the heat provided by the reaction heat of the polymerization reaction in the prepolymerization reactor 2 plus the heat of the glue liquid itself, thereby maintaining the temperature of the prepolymerization reactor 2 within the temperature range required for the grafting reaction.

[0032] Specifically, refer to Figure 2 As shown, the storage bin 1a is provided with a first feed port 1a1 and a first discharge port 1a2, and the prepolymerization reactor 2 is provided with a second feed port 2a and a second discharge port 2b, and the first discharge port 1a2 is sealed and connected with the second feed port 2a through a pipeline. The unheated glue enters the storage bin 1a through the first feed port 1a1, and when the glue reaches a certain temperature in the storage bin 1a, the heated glue leaves the storage bin 1a through the first discharge port 1a2 and enters the prepolymerization reactor 2 through the second feed port 2a through the pipeline.

[0033] Specifically, refer to Figure 2 As shown, the heater 1b is a heating oil pipe 1b1, and the heating oil pipe 1b1 is arranged outside the storage bin 1a, and the two ends of the heating oil pipe 1b1 are respectively an oil inlet 1b2 and an oil outlet 1b3. The flow direction of the heating oil in the heating oil pipe 1b1 is shown as the heating oil flow direction 5. The heating oil with a certain temperature enters the heating oil pipe 1b1 from the oil inlet 1b2, and then leaves the heating oil pipe 1b1 through the oil outlet 1b3. When the heating oil flows in the heating oil pipe 1b1, the heating oil will exchange heat with the heating oil pipe 1b1, and the heating oil pipe 1b1 will exchange heat with the storage bin 1a, so as to heat the storage bin 1a, and then heat the glue in the storage bin 1a.

[0034] The control circuit design scheme between the kettle temperature control main regulator 3a and the oil temperature control sub-regulator 3b is as follows. For details, refer to Figure 2 As shown, the temperature control circuit 3 includes a kettle temperature control main regulator 3a and an oil temperature control sub-regulator 3b, wherein the kettle temperature control main regulator 3a is used to detect the temperature in the prepolymerization reactor 2, and the oil temperature control sub-regulator 3b is used to detect the temperature of the glue output by the glue preheater 1. The kettle temperature control main regulator 3a and the oil temperature control sub-regulator 3b are electrically connected. The design can achieve more precise and accurate temperature control, ensuring that the temperature in the prepolymerization reactor 2 and the temperature of the glue are both within the optimal process range. Through the coordinated work of the kettle temperature control main regulator 3a and the oil temperature control sub-regulator 3b, rapid response and precise adjustment of temperature can be achieved, avoiding production problems caused by temperature fluctuations.

[0035] The control circuit design scheme between the heating oil flow control valve 3c and the oil temperature control sub-regulator 3b is as follows. Specifically, the temperature control circuit 3 includes a heating oil flow control valve 3c, which is arranged at the oil inlet 1b2 of the heating oil pipe 1b1. The heating oil flow control valve 3c is used to control the flow of the heating oil into the heating oil pipe 1b1. The heating oil flow control valve 3c is electrically connected to the oil temperature control sub-regulator 3b. Through the heating oil flow control valve 3c, the inflow of the heating oil into the heating oil pipe 1b1 can be accurately controlled, thereby adjusting the temperature and heating rate of the glue preheater 1. This design helps to achieve accurate control of the temperature of the glue preheater 1, and further improves the accuracy and stability of the temperature in the prepolymerization reactor 2. The connection relationship between the reactor temperature control main regulator 3a, the oil temperature control sub-regulator 3b and the heating oil flow control valve 3c is shown in the temperature control component connection relationship 6.

[0036] The utility model obtains a dedicated operation control system that can ensure that the temperature of the prepolymerization reactor of the HIPS production line is continuously and stably controlled within a very small temperature deviation range through the combination of the above-mentioned various design schemes. The prepolymerization temperature in the HIPS production process can be well controlled within the range required by the production technology, and the polymerization system in the prepolymerization reactor can be ensured to meet the purpose of good rubber grafting polystyrene, so as to obtain high-quality high-impact polystyrene HIPS products.

[0037] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-restrictive from any point of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention. Any reference numeral in a claim should not be regarded as limiting the claim to which it relates.

Claims

1. A temperature control system for a prepolymerization reactor of a HIPS production line, characterized in that: The invention comprises a glue liquid preheater (1), a prepolymerization reactor (2) and a temperature control circuit (3). The glue liquid preheater (1) is matched with the temperature control circuit (3). The glue liquid preheater (1) is used to heat the glue liquid that is about to enter the prepolymerization reactor (2). The temperature control circuit (3) is used to control the working state of the glue liquid preheater (1) to keep the glue liquid in the prepolymerization reactor (2) in a constant temperature state.

2. The temperature control system of the prepolymerization reactor of the HIPS production line according to claim 1, characterized in that: The glue liquid preheater (1) comprises a storage bin (1a) and a heater (1b), wherein the heater (1b) is arranged outside the storage bin (1a), the storage bin (1a) is used to store the glue liquid to be introduced into the prepolymerization reactor (2), and the heater (1b) is used to heat the glue liquid in the storage bin (1a).

3. The temperature control system of the prepolymerization reactor of the HIPS production line according to claim 2, characterized in that: The storage bin (1a) is provided with a first feed port (1a1) and a first discharge port (1a2), and the prepolymerization reactor (2) is provided with a second feed port (2a) and a second discharge port (2b), and the first discharge port (1a2) is sealedly connected to the second feed port (2a) via a pipeline.

4. The temperature control system of the prepolymerization reactor of the HIPS production line according to claim 2, characterized in that: The heater (1b) is a heating oil pipe (1b1), and the heating oil pipe (1b1) is arranged outside the storage bin (1a). The two ends of the heating oil pipe (1b1) are respectively an oil inlet (1b2) and an oil outlet (1b3).

5. The temperature control system of the prepolymerization reactor of the HIPS production line according to claim 1, characterized in that: The temperature control circuit (3) comprises a kettle temperature control main regulator (3a) and an oil temperature control sub-regulator (3b), wherein the kettle temperature control main regulator (3a) is used to detect the temperature in the prepolymerization reactor (2), and the oil temperature control sub-regulator (3b) is used to detect the temperature of the glue output from the glue preheater (1).

6. The temperature control system of the prepolymerization reactor of the HIPS production line according to claim 5, characterized in that: The temperature control circuit (3) comprises a heating oil flow control valve (3c), which is arranged at the oil inlet (1b2) of the heating oil pipe (1b1), and is used to control the flow of heating oil entering the heating oil pipe (1b1).

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