Device for refining cyclopentadiene by depolymerizing dicyclopentadiene

Abstract

The utility model belongs to the technical field of teaching, scientific research and production of chemistry and chemical engineering, and discloses a device for refining cyclopentadiene by depolymerizing dicyclopentadiene. Comprising a raw material storage tank, a feeding pump, an evaporator, a heater, a cracker, a condenser pipe, a first cooler, a first rectifying tower, a second rectifying tower, a second condenser, a receiving tank and a product storage tank which are sequentially connected through pipelines. Raw materials enter the preheating pipe and the evaporator through the feeding pump to be preheated and evaporated, are depolymerized through the heater and the cracker and then are rectified. Before raw materials are preheated, a diluent and a polymerization inhibitor are added and fully stirred and mixed, so that coking in the subsequent high-temperature cracking process can be effectively inhibited, and meanwhile, the rate of subsequent cracking reaction and the concentration of the raw materials can be effectively controlled; cracking is carried out multiple times in the heater and the cracker, the cracking efficiency is effectively improved, and the purity of cyclopentadiene is effectively improved to 97% or above through separation of the double rectifying towers.

Description

Technical Field

[0001] The utility model belongs to the teaching, scientific research and industrial production application fields of chemistry, chemical engineering and environmental science, and relates to an experimental instrument for cracking, distilling and purifying products of compounds. Background Art

[0002] Dicyclopentadiene (DCPD) is a byproduct of petroleum cracking to produce ethylene and a light benzene fraction produced by coal coking. In practical applications, there are three main methods for preparing cyclopentadiene (CPD) by cracking dicyclopentadiene DCPD: low-temperature liquid phase depolymerization, high-temperature liquid phase depolymerization, and high-temperature gas phase depolymerization. The low-temperature liquid phase depolymerization method uses intermittent operation, and the operating temperature is controlled below 200°C. The main advantages are simple equipment and short process route. The disadvantages are slow depolymerization speed and low product yield. The high-temperature liquid phase depolymerization process uses an organic heat carrier and operates continuously at an operating temperature of 200°C to 300°C. The raw materials are quickly dispersed by the heat carrier in the kettle, so that more multipolymers are produced, and the reaction is carried out forward by continuously removing the product CPD from the system. The product yield is greatly improved compared to low-temperature depolymerization. The advantages are simple equipment, short process route, and high efficiency. The disadvantage is that the heavy components in the raw materials are in contact with the high-temperature organic carrier for a long time to produce more polymers, which deteriorates the carrier and blocks the reactor. The high-temperature gas phase depolymerization method adopts continuous operation, and the operating temperature is generally above 300°C. The gasified DCPD is heated to the reaction temperature in a very short time, so that the DCPD is instantly cracked. The advantages are fast depolymerization speed and high yield, and the disadvantages are complex equipment, easy high-temperature coking during operation, and difficult to operate for a long time.

[0003] High-temperature gas-phase depolymerization is the most commonly used method for refining cyclopentadiene. Therefore, it is of great significance to design and develop a new type of device with good cracking performance and high purification performance to improve the purity of cyclopentadiene, reduce the complexity of equipment and reduce coking. Utility Model Content

[0004] The purpose of the utility model is to solve the deficiencies in the prior art and to provide a dicyclopentadiene cracking and refining cyclopentadiene device with high depolymerization efficiency, low equipment complexity, low coking and clogging phenomenon and improved product purity, thereby greatly improving the recovery rate and purity of the product.

[0005] The technical solution of this utility model:

[0006] A device for refining cyclopentadiene by depolymerizing dicyclopentadiene, comprising a raw material storage tank 1, a feed pump 2, an evaporator 3, a heater 4, a cracker 5, a condenser 6, a reboiler 7, a first distillation tower 8, a second distillation tower 9, a reboiler 10, a receiving tank 11 and a product storage tank 12;

[0007] The discharge port at the bottom of the raw material storage tank 1 is connected to the inlet at the upper part of the evaporator 3 side through a pipeline and a feed pump 2, the outlet at the top of the evaporator 3 is connected to the inlet at the bottom of the heater 4 through a pipeline, the outlet at the upper part of the heater 4 side is connected to the inlet at the bottom of the cracker 5 through a pipeline, the outlet at the upper part of the cracker 5 side is connected to the inlet of the first condenser 6, the outlet of the first condenser 6 is connected to the middle inlet of the first distillation tower 8 through a pipeline, the outlet at the top of the first distillation tower 8 is connected to the middle inlet of the second distillation tower 9 through a pipeline, the outlet at the top of the second distillation tower 9 is connected to the inlet of the second condenser 6, and the outlet of the second condenser 6 is connected to the inlet of the receiving tank 11 through a pipeline;

[0008] The outlet at the bottom of the first distillation tower 8 is connected to the right outlet of the reboiler 7 through a pipeline, the left outlet of the reboiler 7 is connected to the top inlet of the raw material storage tank 1, and the inlet at the lower side of the first distillation tower 8 is connected to the outlet at the top of the reboiler 7;

[0009] The outlet at the bottom of the second distillation tower 9 is connected to the right inlet of the reboiler 10 through a pipeline, the lower end outlet of the reboiler 10 is connected to the inlet of the third condenser 6, the outlet of the third condenser 6 is connected to the inlet of the product storage tank 12 through a pipeline, and the outlet of the product storage tank 12 is connected to the outlet at the bottom of the receiving tank 11; the lower inlet on the side of the second distillation tower 9 is connected to the outlet at the top of the reboiler 10 through a pipeline;

[0010] The upper inlet of the second distillation tower 9 is connected to the outlet at the bottom of the receiving tank 11 through a pipeline and a feed pump 2 .

[0011] The device improves the efficiency of depolymerization by extending the length of the cracker and increasing the number of baffles, thereby reducing the number of crackers and simplifying the complexity of the equipment.

[0012] The outer surface of the raw material storage tank is equipped with a heating and insulation layer, which reduces the number of mixing devices such as mechanical stirring tanks and reduces the complexity of the device.

[0013] The purity of cyclopentadiene can be improved by increasing the number of distillation towers and performing multiple distillation operations.

[0014] By using diluents and inhibitors, coking is reduced, achieving the goals of simplicity, safety and efficiency in industrial production.

[0015] Beneficial effects of the utility model: The utility model increases the length of the cracker and the number of baffles, so that the depolymerization efficiency is higher, the number of crackers is reduced, and the equipment is simplified. The use of diluents and inhibitors effectively inhibits the occurrence of coking during high-temperature cracking, and the rate of subsequent cracking reactions and the concentration of raw materials can be controlled; multiple distillations are performed, and the purity of the product is higher. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1It is a structural schematic diagram of the utility model.

[0017] In the figure: 1 raw material storage tank; 2 feed pump; 3 evaporator; 4 heater; 5 cracker; 6 condenser; 7 reboiler; 8 first distillation tower; 9 second distillation tower; 10 reboiler; 11 receiving tank; 12 product storage tank. DETAILED DESCRIPTION

[0018] The specific implementation of the utility model is further described below in conjunction with the accompanying drawings and technical solutions.

[0019] like Figure 1 The device for purifying cyclopentadiene by cracking dicyclopentadiene and the device for purifying cyclopentadiene by depolymerizing dicyclopentadiene shown include a raw material storage tank 1, a feed pump 2, an evaporator 3, a heater 4, a cracker 5, a condenser 6, a reboiler 7, a first distillation tower 8, a second distillation tower 9, a reboiler 10, a receiving tank 11 and a product storage tank 12;

[0020] The discharge port at the bottom of the raw material storage tank 1 is connected to the inlet at the upper part of the evaporator 3 side through a pipeline and a feed pump 2, the outlet at the top of the evaporator 3 is connected to the inlet at the bottom of the heater 4 through a pipeline, the outlet at the upper part of the heater 4 side is connected to the inlet at the bottom of the cracker 5 through a pipeline, the outlet at the upper part of the cracker 5 side is connected to the inlet of the first condenser 6, the outlet of the first condenser 6 is connected to the middle inlet of the first distillation tower 8 through a pipeline, the outlet at the top of the first distillation tower 8 is connected to the middle inlet of the second distillation tower 9 through a pipeline, the outlet at the top of the second distillation tower 9 is connected to the inlet of the second condenser 6, and the outlet of the second condenser 6 is connected to the inlet of the receiving tank 11 through a pipeline;

[0021] The outlet at the bottom of the first distillation tower 8 is connected to the right outlet of the reboiler 7 through a pipeline, the left outlet of the reboiler 7 is connected to the top inlet of the raw material storage tank 1, and the inlet at the lower side of the first distillation tower 8 is connected to the outlet at the top of the reboiler 7;

[0022] The outlet at the bottom of the second distillation tower 9 is connected to the right inlet of the reboiler 10 through a pipeline, the lower end outlet of the reboiler 10 is connected to the inlet of the third condenser 6, the outlet of the third condenser 6 is connected to the inlet of the product storage tank 12 through a pipeline, and the outlet of the product storage tank 12 is connected to the outlet at the bottom of the receiving tank 11; the lower inlet on the side of the second distillation tower 9 is connected to the outlet at the top of the reboiler 10 through a pipeline;

[0023] The upper inlet of the second distillation tower 9 is connected to the outlet at the bottom of the receiving tank 11 through a pipeline and a feed pump 2 .

[0024] Furthermore, the pipelines between the raw material storage tank 1 and the feed pump 2, between the feed pump 2 and the evaporator 3, and between the heater 4 and the cracker 5 are all wrapped with a pipeline insulation layer, and the outer layer of the raw material storage tank 1 is provided with a heating insulation layer.

[0025] Furthermore, the pipeline insulation layer is a heating wire insulation belt, and the heating insulation layer is an electric heating sleeve.

[0026] Furthermore, a switchable ball valve is provided at the bottom end of the evaporator 3 .

[0027] Furthermore, the cracker 5 is provided with a plurality of baffles in the middle to effectively control the flow rate of cracking.

[0028] Furthermore, a switchable ball valve is provided at the bottom of the condenser tube 6 for sampling at any time.

[0029] Furthermore, the first distillation tower 8 and the second distillation tower 9 include a distillation section, a cooling section arranged at the top of the distillation section, and a cooling section tank insulation layer.

[0030] Furthermore, the tank body insulation layer is a rock wool board evenly laid on the outer surface of the heating mechanism.

[0031] Furthermore, the condenser is cooled by coil heat exchange.

[0032] A feed pump 2 is connected between the raw material storage tank 1 and the evaporator 3. Before the raw material enters the top of the evaporator 3 through the feed pump 2, all instruments are pre-set to the corresponding temperature. The raw material evaporates directly after entering the evaporator 3, and the gas reaches the heater 4. After being heated in the heater 4, it enters the cracker 5 through the outlet end of the heater 4 for cracking. The cracked product enters the first distillation tower 8 after being cooled by the condenser 6, and the low-boiling point compound enters the second distillation tower 9 through the distillation section and the condensation section. The high-boiling point compound and the dicyclopentadiene raw material return to the raw material tank to continue the cycle cracking. The product entering the second distillation tower 9 is purified by distillation to obtain a high-purity cyclopentadiene product, and enters the receiving tank 11 after being cooled by the condenser. Adding a feed pump between the receiving tank 11 and the second distillation tower 9 can further purify the purity of the product in the receiving tank.

Claims

1. A device for refining cyclopentadiene by depolymerization of dicyclopentadiene, characterized in that: The dicyclopentadiene depolymerization and purification cyclopentadiene device comprises a raw material storage tank (1), a feed pump (2), an evaporator (3), a heater (4), a cracker (5), a condenser (6), a reboiler (7), a first distillation tower (8), a second distillation tower (9), a reboiler (10), a receiving tank (11) and a product storage tank (12); The discharge port at the bottom of the raw material storage tank (1) is connected to the inlet of the upper part of the evaporator (3) through a pipeline and a feed pump (2); the outlet at the top of the evaporator (3) is connected to the inlet of the bottom of the heater (4) through a pipeline; the outlet at the upper part of the heater (4) is connected to the inlet of the bottom of the cracker (5) through a pipeline; the outlet at the upper part of the cracker (5) is connected to the inlet of the first condenser (6); the outlet of the first condenser (6) is connected to the middle inlet of the first distillation tower (8) through a pipeline; the outlet at the top of the first distillation tower (8) is connected to the middle inlet of the second distillation tower (9) through a pipeline; the outlet at the top of the second distillation tower (9) is connected to the inlet of the second condenser (6); the outlet of the second condenser (6) is connected to the inlet of the receiving tank (11) through a pipeline; The outlet at the bottom of the first distillation tower (8) is connected to the right outlet of the reboiler (7) through a pipeline, the left outlet of the reboiler (7) is connected to the top inlet of the raw material storage tank (1), and the inlet at the lower side of the first distillation tower (8) is connected to the outlet at the top of the reboiler (7); The outlet at the bottom of the second distillation tower (9) is connected to the right inlet of the reboiler (10) through a pipeline, the lower outlet of the reboiler (10) is connected to the inlet of the third condenser (6), the outlet of the third condenser (6) is connected to the inlet of the product storage tank (12) through a pipeline, and the outlet of the product storage tank (12) is connected to the outlet at the bottom of the receiving tank (11); the lower inlet of the side of the second distillation tower (9) is connected to the outlet at the top of the reboiler (10) through a pipeline; The upper inlet of the second distillation tower (9) is connected to the outlet at the bottom of the receiving tank (11) through a pipeline and a feed pump (2).

2. The device for refining cyclopentadiene by depolymerization of dicyclopentadiene according to claim 1, characterized in that: The pipelines between the raw material storage tank (1) and the feed pump (2), between the feed pump (2) and the evaporator (3), and between the heater (4) and the cracker (5) are all wrapped with a pipeline insulation layer, and the outer layer of the raw material storage tank (1) is provided with a heating insulation layer.

3. The device for refining cyclopentadiene by depolymerization of dicyclopentadiene according to claim 2, characterized in that: The pipeline insulation layer is a heating wire insulation belt, and the heating insulation layer is an electric heating sleeve.

4. The device for refining cyclopentadiene by depolymerization of dicyclopentadiene according to claim 1, characterized in that: A switchable ball valve is arranged at the bottom end of the evaporator (3).

5. The device for refining cyclopentadiene by depolymerization of dicyclopentadiene according to claim 1, characterized in that: The cracker (5) is provided with a plurality of baffles in the middle to effectively control the flow rate of cracking.

6. The device for refining cyclopentadiene by depolymerization of dicyclopentadiene according to claim 1, characterized in that: The bottom end of the condenser tube (6) is provided with a switchable ball valve for sampling at any time.

7. The device for refining cyclopentadiene by depolymerization of dicyclopentadiene according to claim 1, characterized in that: The first distillation tower (8) and the second distillation tower (9) comprise a distillation section, a cooling section arranged at the top of the distillation section, and a cooling section tank insulation layer.

8. The device for refining cyclopentadiene by depolymerization of dicyclopentadiene according to claim 7, characterized in that: The tank insulation layer is a rock wool board laid evenly on the outer surface of the heating mechanism.

9. The device for refining cyclopentadiene by depolymerization of dicyclopentadiene according to claim 1, characterized in that: The condenser is cooled by coil heat exchange.

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