Comprehensive heat energy utilization device for propylene carbonate device

Abstract

The utility model relates to a comprehensive heat energy utilization device of a propylene carbonate device. According to the technical scheme, the lower end of an epoxypropane storage tank is connected to a side line of a first propylene carbonate reactor through a pipeline and an epoxypropane circulating pump and is further connected to a tube pass outlet of a carbon dioxide vaporizer through a pipeline, and a tube pass inlet is connected with a liquid-phase carbon dioxide storage tank through a pipeline; the lower side of the first propylene carbonate reactor is connected with the second propylene carbonate reactor through a pipeline, the side line is connected to the side line of the rectifying still through a pipeline, the bottom is connected with a shell pass inlet of the heat exchanger through a pipeline, and a shell pass outlet of the heat exchanger is connected to the top of the first propylene carbonate reactor through a pipeline and a propylene carbonate crude product circulating pump. The heating device has the beneficial effects that on one hand, the cooling capacity during gasification of the liquid-phase carbon dioxide is fully utilized, and on the other hand, the high-temperature heat of the propylene carbonate reactor is fully utilized and is applied to heating of the rectifying still, so that the energy consumption is reduced.

Description

Technical Field

[0001] This utility model relates to the field of propylene carbonate preparation technology, and in particular to a device for comprehensive utilization of thermal energy in propylene carbonate production. Background Technology

[0002] Propylene carbonate is a colorless, transparent liquid with low toxicity, low volatility, and good solubility, making it widely used in battery manufacturing. As a solvent for the liquid electrolyte in lithium-based batteries, propylene carbonate plays a crucial role in battery manufacturing due to its high dielectric constant, high solubility for lithium salts, and wide liquid range.

[0003] Currently, propylene carbonate is synthesized industrially from propylene oxide and carbon dioxide. The raw material, carbon dioxide, is vaporized in a steam vaporizer and then enters the reactor to participate in the reaction. The production process of synthesizing propylene carbonate is high temperature and high pressure. A large amount of heat is released during the reaction in the reactor, which is cooled by an external radiator. In addition, the distillation kettle in the dimethyl carbonate section also requires high temperature, resulting in high energy consumption. The high-temperature heat in the propylene carbonate reactor is not fully utilized. Furthermore, the existing cooling methods rely on cooling water, which is also energy-intensive, and the cooling energy generated during the vaporization of liquid carbon dioxide is not fully utilized and is wasted. Utility Model Content

[0004] The purpose of this invention is to address the aforementioned deficiencies in the existing technology by providing a comprehensive thermal energy utilization device for a propylene carbonate plant. This device fully utilizes the cooling energy during the vaporization of liquid carbon dioxide and the high-temperature heat from the propylene carbonate reactor, applying it to the heating of the distillation kettle, thereby reducing energy consumption.

[0005] This utility model discloses a comprehensive thermal energy utilization device for a propylene carbonate plant. The technical solution includes: a first propylene carbonate reactor (T101), a second propylene carbonate reactor (T102), a carbon dioxide vaporizer (C201), a heat exchanger (E201), a dimethyl carbonate unit (T302), a distillation kettle (T301), a propylene oxide storage tank (V101), a liquid carbon dioxide storage tank (V201), a cold medium storage tank (V202), a propylene oxide circulation pump (P101), and a crude propylene carbonate circulation pump (P201). The lower end of the propylene oxide storage tank (V101) is connected to the side line of the first propylene carbonate reactor (T101) via a pipeline and the propylene oxide circulation pump (P101). The side line of the reactor (T101) is connected to the tube-side outlet of the carbon dioxide vaporizer (C201) via a pipeline, and the tube-side inlet of the carbon dioxide vaporizer (C201) is connected to the liquid phase carbon dioxide storage tank (V201) via a pipeline; the lower side of the first propylene carbonate reactor (T101) is connected to the second propylene carbonate reactor (T102) via a pipeline, and the side line of the second propylene carbonate reactor (T102) is connected to the side line of the distillation kettle (T301) via a pipeline; the bottom of the first propylene carbonate reactor (T101) is connected to the shell-side inlet of the heat exchanger (E201) via a pipeline, and the shell-side outlet of the heat exchanger (E201) is connected to the top of the first propylene carbonate reactor (T101) via a pipeline and the crude propylene carbonate circulation pump (P201).

[0006] Preferably, the tube-side outlet of the heat exchanger (E201) is connected to the lower side of the distillation vessel (T301) via a pipeline, and the upper side of the distillation vessel (T301) is connected to the tube-side inlet of the heat exchanger (E201) via a pipeline.

[0007] Preferably, the shell-side inlet of the aforementioned carbon dioxide vaporizer (C201) is connected to a refrigerant storage tank (V202), and the shell-side outlet of the carbon dioxide vaporizer (C201) is connected to a dimethyl carbonate unit (T302) via a pipeline.

[0008] Preferably, the dimethyl carbonate device (T302) described above is connected to the upper end of the refrigerant storage tank (V202) via a circulation pipeline.

[0009] Preferably, the bottom of the aforementioned propylene carbonate second reactor (T102) is connected to the shell-side inlet of the heat exchanger (E201) via a pipeline and a control valve (Q1).

[0010] The beneficial effects of this invention are as follows: By sending liquid carbon dioxide into a carbon dioxide vaporizer, the vaporization process is endothermic, thereby cooling the cold medium and making full use of the cooling capacity. Furthermore, since the reaction in the first propylene carbonate reactor is at high temperature and pressure, the high-temperature crude propylene carbonate is sent to a heat exchanger to reheat the material from the distillation vessel, fully utilizing the high temperature of the first propylene carbonate reactor. The cooled crude propylene carbonate is then pumped back to the top of the first propylene carbonate reactor via a crude propylene carbonate circulation pump, forming a circulating heating cycle. Then, the side line of the first propylene carbonate reactor is connected to the second propylene carbonate reactor to continue the reaction. Finally, the reaction product is sent to the distillation vessel for distillation. This invention fully utilizes both the cooling capacity during liquid carbon dioxide vaporization and the high-temperature heat of the propylene carbonate reactor, applying it to the heating of the distillation vessel, thus reducing energy consumption. Attached Figure Description

[0011] Figure 1 This is a connection diagram of Embodiment 1 of this utility model;

[0012] Figure 2 This is a connection diagram of Embodiment 2 of this utility model;

[0013] Figure 3 This is a connection diagram of Embodiment 3 of this utility model;

[0014] In the diagram above: Propylene carbonate reactor T101, propylene carbonate reactor T102, carbon dioxide vaporizer C201, heat exchanger E201, distillation vessel T301, dimethyl carbonate unit T302, propylene oxide storage tank V101, liquid carbon dioxide storage tank V201, cold medium storage tank V202, propylene oxide circulation pump P101, crude propylene carbonate circulation pump P201, control valve Q1, reboiler H301. Detailed Implementation

[0015] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0016] Example 1, referring to Figure 1The present invention relates to a comprehensive thermal energy utilization device for a propylene carbonate plant. The technical solution includes: a first propylene carbonate reactor T101, a second propylene carbonate reactor T102, a carbon dioxide vaporizer C201, a heat exchanger E201, a dimethyl carbonate unit T302, a distillation kettle T301, a propylene oxide storage tank V101, a liquid carbon dioxide storage tank V201, a cold medium storage tank V202, a propylene oxide circulation pump P101, and a crude propylene carbonate circulation pump P201. The lower end of the propylene oxide storage tank V101 is connected to the side of the first propylene carbonate reactor T101 via a pipeline and the propylene oxide circulation pump P101. The side line of reactor T101 is connected to the tube-side outlet of carbon dioxide vaporizer C201 via a pipeline, and the tube-side inlet of carbon dioxide vaporizer C201 is connected to liquid phase carbon dioxide storage tank V201 via a pipeline; the lower side of the first propylene carbonate reactor T101 is connected to the second propylene carbonate reactor T102 via a pipeline, and the side line of the second propylene carbonate reactor T102 is connected to the side line of distillation kettle T301 via a pipeline; the bottom of the first propylene carbonate reactor T101 is connected to the shell-side inlet of heat exchanger E201 via a pipeline, and the shell-side outlet of heat exchanger E201 is connected to the top of the first propylene carbonate reactor T101 via a pipeline and the crude propylene carbonate circulation pump P201.

[0017] The tube-side outlet of the heat exchanger E201 is connected to the lower side of the distillation vessel T301 via a pipeline, and the upper side of the distillation vessel T301 is connected to the tube-side inlet of the heat exchanger E201 via a pipeline.

[0018] The shell-side inlet of the aforementioned carbon dioxide vaporizer C201 is connected to the refrigerant storage tank V202, and the shell-side outlet of the carbon dioxide vaporizer C201 is connected to the dimethyl carbonate unit T302 via a pipeline.

[0019] When using this utility model,

[0020] Propylene oxide in propylene oxide storage tank V101 is fed into the first propylene carbonate reactor T101 via propylene oxide circulation pump P101. Liquid carbon dioxide in liquid carbon dioxide storage tank V201 is fed into carbon dioxide vaporizer C201. The vaporization process is endothermic, thus cooling the cold medium from cold medium storage tank V202, thereby making full use of the cooling capacity. The cooled cold medium is then fed into dimethyl carbonate unit T302 for further utilization. The reaction in the first propylene carbonate reactor T101 is high-temperature and high-pressure, thus sending the high-temperature crude propylene carbonate to heat exchanger E201 for further processing of the material from distillation vessel T301. Heating fully utilizes the high temperature of the first propylene carbonate reactor T101. The cooled crude propylene carbonate is then sent back to the top of the first propylene carbonate reactor T101 via the crude propylene carbonate circulation pump P201, forming a circulating heating process. Then, the side line of the first propylene carbonate reactor T101 is connected to the second propylene carbonate reactor T102 to continue the reaction. Finally, the reaction product is sent to the distillation kettle T301 for distillation. The entire process makes full use of the cooling energy during the vaporization of liquid carbon dioxide and the high temperature heat of the propylene carbonate reactor, applying it to the heating of the distillation kettle, thus reducing energy consumption.

[0021] Example 2: The technical solution of the thermal energy comprehensive utilization device of the propylene carbonate plant mentioned in this utility model is as follows: it includes a first propylene carbonate reactor T101, a second propylene carbonate reactor T102, a carbon dioxide vaporizer C201, a heat exchanger E201, a dimethyl carbonate unit T302, a distillation kettle T301, a propylene oxide storage tank V101, a liquid carbon dioxide storage tank V201, a cold medium storage tank V202, a propylene oxide circulation pump P101, and a crude propylene carbonate circulation pump P201. The lower end of the propylene oxide storage tank V101 is connected to the side line of the first propylene carbonate reactor T101 via a pipeline and the propylene oxide circulation pump P101. The side line of reactor T101 is connected to the tube-side outlet of carbon dioxide vaporizer C201 via a pipeline, and the tube-side inlet of carbon dioxide vaporizer C201 is connected to liquid phase carbon dioxide storage tank V201 via a pipeline; the lower side of the first propylene carbonate reactor T101 is connected to the second propylene carbonate reactor T102 via a pipeline, and the side line of the second propylene carbonate reactor T102 is connected to the side line of distillation kettle T301 via a pipeline; the bottom of the first propylene carbonate reactor T101 is connected to the shell-side inlet of heat exchanger E201 via a pipeline, and the shell-side outlet of heat exchanger E201 is connected to the top of the first propylene carbonate reactor T101 via a pipeline and the crude propylene carbonate circulation pump P201.

[0022] The difference from Example 1 is:

[0023] In this embodiment, the dimethyl carbonate device T302 is connected to the upper end of the refrigerant storage tank V202 via a circulation pipeline, allowing the refrigerant to be recycled and then fed back into the carbon dioxide vaporizer C201 for cooling, thus achieving recycling.

[0024] Example 3: The technical solution of the thermal energy comprehensive utilization device of the propylene carbonate plant mentioned in this utility model is as follows: it includes a first propylene carbonate reactor T101, a second propylene carbonate reactor T102, a carbon dioxide vaporizer C201, a heat exchanger E201, a dimethyl carbonate unit T302, a distillation kettle T301, a propylene oxide storage tank V101, a liquid carbon dioxide storage tank V201, a cold medium storage tank V202, a propylene oxide circulation pump P101, and a crude propylene carbonate circulation pump P201. The lower end of the propylene oxide storage tank V101 is connected to the side line of the first propylene carbonate reactor T101 through a pipeline and the propylene oxide circulation pump P101. The side line of reactor T101 is connected to the tube-side outlet of carbon dioxide vaporizer C201 via a pipeline, and the tube-side inlet of carbon dioxide vaporizer C201 is connected to liquid phase carbon dioxide storage tank V201 via a pipeline; the lower side of the first propylene carbonate reactor T101 is connected to the second propylene carbonate reactor T102 via a pipeline, and the side line of the second propylene carbonate reactor T102 is connected to the side line of distillation kettle T301 via a pipeline; the bottom of the first propylene carbonate reactor T101 is connected to the shell-side inlet of heat exchanger E201 via a pipeline, and the shell-side outlet of heat exchanger E201 is connected to the top of the first propylene carbonate reactor T101 via a pipeline and the crude propylene carbonate circulation pump P201.

[0025] The difference from Example 2 is:

[0026] Reference Figure 3 In this embodiment, the bottom of the second propylene carbonate reactor T102 is connected to the shell-side inlet of the heat exchanger E201 via a pipeline and control valve Q1. This allows the heat from the second propylene carbonate reactor T102 to be utilized as needed based on site conditions, thus reducing energy consumption.

[0027] The above description is merely a preferred embodiment of this utility model. Any person skilled in the art may modify this utility model or modify it into an equivalent technical solution using the technical solutions described above. Therefore, any simple modifications or equivalent transformations made based on the technical solutions of this utility model are within the scope of protection claimed by this utility model.

Claims

1. A device for comprehensive utilization of thermal energy from a propylene carbonate plant, characterized in that: The reactor includes a first propylene carbonate reactor (T101), a second propylene carbonate reactor (T102), a carbon dioxide vaporizer (C201), a heat exchanger (E201), a dimethyl carbonate unit (T302), a distillation kettle (T301), a propylene oxide storage tank (V101), a liquid carbon dioxide storage tank (V201), a refrigerant storage tank (V202), a propylene oxide circulation pump (P101), and a crude propylene carbonate circulation pump (P201). The lower end of the propylene oxide storage tank (V101) is connected to the side line of the first propylene carbonate reactor (T101) via pipelines and the propylene oxide circulation pump (P101). The side line of the first propylene carbonate reactor (T101) is connected via pipelines... The tube-side outlet of the carbon dioxide vaporizer (C201) is connected to the liquid phase carbon dioxide storage tank (V201) via a pipeline; the lower side of the first propylene carbonate reactor (T101) is connected to the second propylene carbonate reactor (T102) via a pipeline; the side line of the second propylene carbonate reactor (T102) is connected to the side line of the distillation kettle (T301) via a pipeline; the bottom of the first propylene carbonate reactor (T101) is connected to the shell-side inlet of the heat exchanger (E201) via a pipeline; the shell-side outlet of the heat exchanger (E201) is connected to the top of the first propylene carbonate reactor (T101) via a pipeline and the crude propylene carbonate circulation pump (P201).

2. The thermal energy comprehensive utilization device of a propylene carbonate plant according to claim 1, characterized in that: The tube-side outlet of the heat exchanger (E201) is connected to the lower side of the distillation vessel (T301) via a pipeline, and the upper side of the distillation vessel (T301) is connected to the tube-side inlet of the heat exchanger (E201) via a pipeline.

3. The thermal energy comprehensive utilization device for a propylene carbonate plant according to claim 2, characterized in that: The shell-side inlet of the carbon dioxide vaporizer (C201) is connected to the refrigerant storage tank (V202), and the shell-side outlet of the carbon dioxide vaporizer (C201) is connected to the dimethyl carbonate unit (T302) via a pipeline.

4. The thermal energy comprehensive utilization device for a propylene carbonate plant according to claim 3, characterized in that: The dimethyl carbonate unit (T302) is connected to the upper end of the refrigerant storage tank (V202) via a circulation pipeline.

5. A thermal energy comprehensive utilization device for a propylene carbonate plant according to claim 4, characterized in that: The bottom of the propylene carbonate second reactor (T102) is connected to the shell-side inlet of the heat exchanger (E201) via a pipeline and control valve (Q1).

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