Dehydrocarbonylation apparatus for producing food-grade carbon dioxide

Abstract

The utility model discloses a kind of for producing food-grade carbon dioxide's dehydrocarbon device, it is related to carbon dioxide preparation technical field, it includes the raw material pretreatment component of raw material gas being compressed and desulfurization treatment, raw material gas is transported to first dehydrocarbon reactor, first dehydrocarbon reactor carries out purification to raw material gas;Oxygen supply component is provided for first dehydrocarbon reactor, oxygen supply component is equipped with the oxygen delivery control gas-saving valve between first dehydrocarbon reactor, and is equipped in first dehydrocarbon reactor outlet, for detecting the temperature detector of purified gas temperature, when detecting temperature exceeds preset value, gas-saving valve reduces the oxygen delivery amount of first dehydrocarbon reactor, adjust the temperature in first dehydrocarbon reactor, the above-mentioned dehydrocarbon device, when hydrocarbon content in raw material gas is higher in the existing carbon dioxide production process, dehydrocarbon reactor heats up fast, leading to reactor damage, and when output gas is cooled, consume more circulating water, waste energy technical problem.

Description

Technical Field

[0001] This utility model relates to the field of carbon dioxide preparation technology, and in particular to a dehydrocarbonation device for producing food-grade carbon dioxide. Background Technology

[0002] Carbon dioxide has a wide range of applications, including food processing, machinery manufacturing, and chemical raw materials. It is typically produced by purifying petrochemical tail gas. Currently, equipment for producing food-grade carbon dioxide uses upstream feed gas containing high concentrations of carbon dioxide, small amounts of sulfur, H2, alkanes, benzene, olefins, and alcohols. To ensure that sulfur and hydrocarbon impurities are removed to below food-grade carbon dioxide levels, a slight excess of oxygen is added. After compression, the gas enters a desulfurization process to reduce sulfur levels to below 0.1 ppm. Then, it enters a dehydrocarbonation process where hydrocarbons such as alkanes, benzene, and alcohols react with oxygen in a catalyst-equipped reactor to convert them into carbon dioxide. However, in actual production, when the upstream carbon dioxide feed gas has a high hydrocarbon content, the temperature in the dehydrocarbonation reactor rises rapidly, easily causing a "runaway" reaction that burns the catalyst. Furthermore, subsequent cooling with water is required, consuming circulating water and resulting in underutilization of energy.

[0003] In summary, developing a carbon dioxide dehydrogenation device that can avoid "temperature runaway" in the dehydrogenation reactor and recover some of the heat is a problem that urgently needs to be solved by those skilled in the art. Utility Model Content

[0004] The purpose of this invention is to provide a dehydrocarbonation device for producing food-grade carbon dioxide, which solves the technical problems in the existing carbon dioxide production process where the dehydrocarbonation reactor heats up quickly when the hydrocarbon content in the raw gas is high, leading to reactor damage, and consumes more circulating water and wastes energy when the produced gas is cooled.

[0005] To achieve the above objectives, this utility model provides a dehydrocarbonation device for producing food-grade carbon dioxide:

[0006] The raw material pretreatment component is used to compress and desulfurize the raw material gas. The raw material pretreatment component delivers the raw material gas to the first dehydrocarbonization reactor. The first dehydrocarbonization reactor is used to react the hydrocarbon gases in the raw material gas and generate purified gas.

[0007] An oxygen supply assembly provides oxygen for the first dehydrogenation reactor. A throttle valve for controlling oxygen supply is provided between the oxygen supply assembly and the first dehydrogenation reactor, and a thermometer located at the outlet of the first dehydrogenation reactor for detecting the temperature of the purified gas is provided. When the temperature detected by the thermometer exceeds the preset value, the throttle valve adjusts the valve opening to reduce the amount of oxygen supplied to the first dehydrogenation reactor, thereby regulating the temperature inside the first dehydrogenation reactor.

[0008] Preferably, the raw material pretreatment component includes a gas compressor and a desulfurization tower. The gas compressor compresses the raw material gas to a specified reaction gas pressure, and the gas compressor delivers the raw material gas to the desulfurization tower, which is used to remove sulfides from the raw material gas.

[0009] Preferably, the first dehydrocarbonation reactor is connected to a second dehydrocarbonation reactor, the second dehydrocarbonation reactor is connected to an oxygen supply component, a throttle valve is connected between the oxygen supply component and the second dehydrocarbonation reactor, a temperature measuring instrument is provided at the outlet of the second dehydrocarbonation reactor, and the second dehydrocarbonation reactor is used to increase the concentration of carbon dioxide in the purified gas.

[0010] Preferably, the desulfurization tower is connected to a heat exchanger, which is used to preheat the raw material gas.

[0011] Preferably, both the first dehydrocarbonization reactor and the second dehydrocarbonization reactor are connected to a hydrothermal separator via a heat recovery unit. The heat recovery unit receives cooling water from the hydrothermal separator to absorb heat from the purified gas.

[0012] Preferably, the second dehydrocarbonization reactor is connected to a heat exchanger, and the second dehydrocarbonization reactor provides the heat exchanger with purified gas for preheating the feed gas.

[0013] Preferably, the outlet of the second dehydrocarbonization reactor is also equipped with an oxygen analyzer, which is used to determine whether the dehydrocarbonization reaction has been carried out sufficiently.

[0014] Preferably, each heat recovery unit is either a forced circulation heat exchanger or a thermosiphon heat exchanger.

[0015] Preferably, the heat exchanger is connected to the cooler, which is used to condense and purify the water vapor in the gas.

[0016] Preferably, a dehydrogenation electric heater is connected between the heat exchanger and the first dehydrogenation reactor to heat the feed gas to a specified reaction temperature.

[0017] Compared to the aforementioned background technology, the dehydrocarbonation device for producing food-grade carbon dioxide provided by this utility model includes: a raw material pretreatment component, which compresses the raw material gas to a specified reaction gas pressure and performs desulfurization treatment on the compressed raw material gas; the raw material pretreatment component delivers the raw material gas to a first dehydrocarbonation reactor; the first dehydrocarbonation reactor is connected to an oxygen supply component, which supplies oxygen to the first dehydrocarbonation reactor; the first dehydrocarbonation reactor reacts the hydrocarbon gases in the raw material gas into carbon dioxide and water; a throttle valve is connected between the oxygen supply component and the first dehydrocarbonation reactor to control the amount of oxygen supplied to the first dehydrocarbonation reactor; a connecting plate thermometer is provided at the port of the first dehydrocarbonation reactor, which detects the temperature of the purified gas produced by the first dehydrocarbonation reactor; the thermometer is signal-connected to the throttle valve; when the temperature detected by the thermometer is greater than a preset temperature, the throttle valve adjusts its opening to reduce the oxygen supplied to the first dehydrocarbonation reactor, slowing down the dehydrocarbonation reaction and preventing excessively rapid heat generation from damaging the reaction device and the internal catalyst. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of a dehydrocarbonation device for producing food-grade carbon dioxide, provided in an embodiment of this utility model.

[0020] Among them, 1-first dehydrocarbonization reactor; 2-gas compressor; 3-desulfurization tower; 4-heat exchanger; 5-dehydrocarbonization electric heater; 6-second dehydrocarbonization reactor; 7-heat recovery unit; 8-water-heat separator; 9-thermal measuring instrument; 10-throttle valve; 11-oxygen analyzer; 12-cooler; 13-oxygen supply assembly. Detailed Implementation

[0021] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0022] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0023] This invention provides a dehydrocarbonation device for producing food-grade carbon dioxide. Please refer to the appendix of the instruction manual. Figure 1 The dehydrocarbon removal device includes a feedstock pretreatment component, which compresses the feedstock gas to a specified reaction pressure. The feedstock pretreatment component then desulfurizes the feedstock gas and delivers the desulfurized feedstock gas to the first dehydrocarbon removal reactor 1. Further, the first dehydrocarbon removal reactor 1 is connected to an oxygen supply component 13, which supplies oxygen to the first dehydrocarbon removal reactor 1. During the dehydrocarbon removal process in the first dehydrocarbon removal reactor 1, oxygen reacts with hydrocarbon compounds to generate carbon dioxide and water vapor, releasing heat simultaneously. A section is installed between the first dehydrocarbon removal reactor 1 and the oxygen supply component 13. The gas valve 10 controls the oxygen supply rate of the oxygen supply component 13 to the first dehydrogenation reactor 1 by adjusting its own valve opening, thereby adjusting the reaction rate of the dehydrogenation reaction. A thermometer 9 is installed at the outlet of the first dehydrogenation reactor 1 to detect the temperature of the purified gas processed by the first dehydrogenation reactor 1. When the detected purified gas temperature is higher than the preset temperature, the thermometer 9 sends a control signal to the gas valve 10, which reduces its own valve opening, thereby reducing the rate at which the oxygen supply component 13 supplies oxygen to the first dehydrogenation reactor 1, slowing down the dehydrogenation reaction process, and consequently reducing the heat generated by the dehydrogenation reaction.

[0024] This application sets up a throttle valve 10 on the oxygen delivery path to regulate the oxygen delivery efficiency, and sets up a thermometer 9 at the outlet of the first dehydrocarbon reactor 1 to monitor the temperature inside the reaction device in real time. This allows the throttle valve 10 to adjust its opening degree according to the temperature inside the reaction device, thereby regulating the reaction rate and preventing the reaction device from overheating.

[0025] Please continue to refer to the instruction manual appendix. Figure 1 The raw material pretreatment device includes a gas compressor 2 and a desulfurization tower 3. The gas compressor 2 is connected to the desulfurization tower 3. The gas compressor 2 compresses the raw material gas to a specified reaction gas pressure. Preferably, the compressed raw material gas pressure ranges from 2.0 to 2.8 MPa. The gas compressor 2 delivers the raw material gas to the desulfurization tower 3. The desulfurization tower 3 removes sulfides from the raw material gas through a "wet oxidation-absorption" method. It should be noted that, in addition to accelerating the reaction rate of the dehydrocarbonization reaction, the compressed raw material gas can also compensate for the pressure loss of the raw material gas flow through the desulfurization tower 3, the reaction device, and other equipment, enabling the raw material gas to overcome the resistance between various components, maintain the continuous flow of the raw material gas, and make the carbon dioxide dehydrocarbonization reaction more continuous and efficient.

[0026] Furthermore, the first dehydrocarbonization reactor 1 is also connected to a second dehydrocarbonization reactor 6. The first dehydrocarbonization reactor 1 delivers the purified gas produced by the reaction to the second dehydrocarbonization reactor 6. Preferably, the second dehydrocarbonization reactor 6 is also connected to an oxygen supply component 13. The second dehydrocarbonization reactor 6 receives oxygen from the oxygen supply component 13 and continues to dehydrocarbonize the purified gas. This step is used to increase the carbon dioxide concentration in the purified gas. In addition, a throttle valve 10 is also provided between the second dehydrocarbonization reactor 6 and the oxygen supply component 13. A thermometer 9 is also provided at the outlet of the second dehydrocarbonization reactor 6. The thermometer 9 is used to detect the temperature of the purified gas after further dehydrocarbonization. When the temperature of the purified gas exceeds the preset temperature, the throttle valve 10 reduces its own valve opening, slowing down the oxygen delivery efficiency to the second dehydrocarbonization reactor 6 and preventing the second dehydrocarbonization reactor 6 from overheating. Preferably, a connection is made at the outlet of the second dehydrocarbonization reactor 6. An oxygen analyzer 11 is provided to detect the concentration of oxygen in the output purified gas. It should be noted that, in order to ensure that the hydrocarbon compounds in the raw gas can be fully reacted, the oxygen supply component 13 often supplies more oxygen than the standard specified amount to the first dehydrogenation reactor 1 and the second dehydrogenation reactor 6. After the hydrocarbon compounds in the raw gas are fully reacted, a certain concentration of unconsumed oxygen will inevitably remain in the purified gas. That is to say, if the oxygen analyzer 11 at the outlet of the second dehydrogenation reactor 6 does not detect the presence of oxygen in the purified gas, or if the oxygen concentration is less than the specified range, it means that the hydrocarbon compounds in the purified gas have not been fully reacted. Preferably, the oxygen analyzer 11 is connected to a detection terminal signal. When the oxygen analyzer 11 detects that the oxygen concentration in the purified gas is abnormal, it sends a warning signal to the detection terminal to remind the staff to adjust the dehydrogenation device.

[0027] Preferably, each heat recovery unit 7 can be specifically either a forced circulation heat exchanger or a thermosiphon heat exchanger.

[0028] Preferably, several reaction components with the same configuration as the second dehydrocarbonization reactor 6 can be connected in series after the second dehydrocarbonization reactor 6. Correspondingly, the oxygen analyzer 11 is set at the outlet of the last reaction component. In actual production, the staff can roughly detect the concentration range of hydrocarbon compounds in the raw gas, and then connect an appropriate number of reaction components in series with the first dehydrocarbonization reactor 1 and the second dehydrocarbonization reactor 6 to achieve multiple purifications of the raw gas and ensure that the purified gas produced by the reaction meets the specified indicators.

[0029] Preferably, both the first dehydrocarbonization reactor 1 and the second dehydrocarbonization reactor 6 are connected to a heat recovery unit 7, which is connected to a water-heat separator 8. The water-heat separator 8 is provided with a port for receiving external cooling water. Preferably, the port for receiving cooling water is located in the middle part of the side wall of the water-heat separator 8. The bottom of the water-heat separator 8 is connected to the cold source inlet of the heat recovery unit 7, and the cold source outlet of the heat recovery unit 7 is connected to the middle part of the side wall of the water-heat separator 8. It should be noted that the heat recovery unit 7 is provided with non-interconnected cooling pipe sections and heating pipe sections. Cooling water flows in the cooling pipe sections, and purified gas flows in the heating pipe sections. The purified gas after the dehydrocarbonization reaction has a high temperature and can heat the cooling water in the nearby cooling pipe sections. After being heated for a certain period of time, the cooling water boils and evaporates to generate water vapor, which flows to the outside from the top of the water-heat separator 8. The heat generated by the dehydrocarbonization reaction is stored in the water vapor, which can be used by workers in other fields of operation.

[0030] A heat exchanger 4 is connected to the heat recovery unit 7, which is connected to the second dehydrogenation reactor 6. The heat exchanger 4 is located at the outlet of the desulfurization tower 3. A dehydrogenation electric heater 5 is connected between the heat exchanger 4 and the first dehydrogenation reactor 1. The dehydrogenation electric heater 5 is used to heat the raw material gas to a specified reaction temperature. Preferably, the pipeline for transporting the raw material gas in the heat exchanger 4 is not connected to the pipeline for transporting the purified gas. When the dehydrogenation operation of the dehydrogenation unit completes the first cycle, that is, when the purified gas flows back into the heat exchanger 4, the purified gas preheats the raw material gas, increases the initial temperature of the raw material gas when it enters the dehydrogenation electric heater 5, reduces the electrical energy consumed by the dehydrogenation electric heater 5 to heat the raw material gas to the specified reaction temperature, and at the same time increases the reaction rate of the dehydrogenation operation.

[0031] Preferably, the pipe for conveying purified gas in the heat exchanger 4 is connected to the cooler 12. The cooler 12 is equipped with a circulating water pipe. The cooling water in the circulating water pipe cools the purified gas, causing the water vapor in the purified gas to condense, ensuring that the produced carbon dioxide is sufficiently dry.

[0032] In one embodiment of this application, a set of dehydrogenation devices, including a first dehydrogenation reactor 1 and a second dehydrogenation reactor 6, operates continuously. A gas compressor 2 compresses the raw material gas to a specified reaction pressure and delivers it to a desulfurization tower 3 to remove sulfides. The desulfurized raw material gas is then delivered to a heat exchanger 4 for preheating. The heat exchanger 4 delivers the raw material gas to a dehydrogenation electric heater 5, heating it to a specified reaction temperature. Subsequently, the dehydrogenation electric heater 5 delivers the raw material gas to the first dehydrogenation reactor 1. The first dehydrogenation reactor 1 receives oxygen from an oxygen supply assembly 13 and converts the hydrocarbon compounds in the raw material gas into carbon dioxide and water vapor, discharging purified gas from the outlet. The first dehydrogenation reactor 1 delivers the purified gas to a heat recovery unit 7, which absorbs the heat from the purified gas through a water-heat separator 8 and then delivers the purified gas to the second dehydrogenation reactor 6. Inside reactor 6, the dehydrocarbonization reaction is carried out again to increase the concentration of carbon dioxide in the purified gas. Similarly, the heat recovery unit 7 and the water-heat separator 8, which are connected to the second dehydrocarbonization reactor 6, further absorb the heat generated by the dehydrocarbonization reaction, thereby improving the heat recovery rate in the carbon dioxide production process. The second dehydrocarbonization reactor 6 transports the purified gas to the heat exchanger 4 to preheat the subsequent raw material gas, thereby increasing the dehydrocarbonization reaction rate and further improving the heat recovery rate of the dehydrocarbonization reaction. Finally, the cooler 12 cools the purified gas and condenses the water vapor in the purified gas to ensure that the produced carbon dioxide is dry. It should be noted that when the first dehydrocarbonization reactor 1 and the second dehydrocarbonization reactor 6 are working, the temperature measuring instrument 9 monitors the temperature in each reaction device in real time and controls the rate of the dehydrocarbonization reaction through the throttle valve 10 to prevent the temperature in the reaction device from rising too quickly.

[0033] It should be noted that in this specification, relational terms such as first and second are used only to distinguish one entity from several other entities, and do not necessarily require or imply any such actual relationship or order between these entities.

[0034] This article uses specific examples to illustrate the principles and implementation methods of this utility model. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of this utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made to this utility model without departing from the principles of this utility model, and these improvements and modifications also fall within the protection scope of this utility model.

Claims

1. A dehydrocarbonization apparatus for producing food-grade carbon dioxide, characterized in that, include: A raw material pretreatment component is used to compress and desulfurize the raw material gas. The raw material pretreatment component delivers the raw material gas to a first dehydrocarbon reactor (1). The first dehydrocarbon reactor (1) is used to react the hydrocarbon gases in the raw material gas and generate purified gas. An oxygen supply assembly (13) provides oxygen for dehydrogenation to the first dehydrogenation reactor (1). A throttle valve (10) for controlling oxygen supply is provided between the oxygen supply assembly (13) and the first dehydrogenation reactor (1). A thermometer (9) is provided at the outlet of the first dehydrogenation reactor (1) for detecting the temperature of the purified gas. When the temperature detected by the thermometer (9) exceeds the preset value, the throttle valve (10) adjusts the valve opening to reduce the amount of oxygen supplied to the first dehydrogenation reactor (1) in order to regulate the temperature inside the first dehydrogenation reactor (1).

2. The dehydrocarbonization apparatus for producing food-grade carbon dioxide according to claim 1, characterized in that, The raw material pretreatment component includes a gas compressor (2) and a desulfurization tower (3). The gas compressor (2) compresses the raw material gas to a specified reaction gas pressure and delivers the raw material gas to the desulfurization tower (3). The desulfurization tower (3) is used to remove sulfides from the raw material gas.

3. The dehydrocarbonization apparatus for producing food-grade carbon dioxide according to claim 2, characterized in that, The first dehydrogenation reactor (1) is connected to the second dehydrogenation reactor (6), the second dehydrogenation reactor (6) is connected to the oxygen supply component (13), the oxygen supply component (13) and the second dehydrogenation reactor (6) are connected by the gas throttle valve (10), the outlet of the second dehydrogenation reactor (6) is provided with the thermometer (9), and the second dehydrogenation reactor (6) is used to increase the concentration of carbon dioxide in the purified gas.

4. The dehydrocarbonization apparatus for producing food-grade carbon dioxide according to claim 3, characterized in that, The desulfurization tower (3) is connected to a heat exchanger (4), which is used to preheat the raw material gas.

5. The dehydrocarbonization apparatus for producing food-grade carbon dioxide according to claim 3, characterized in that, Both the first dehydrocarbon reactor (1) and the second dehydrocarbon reactor (6) are connected to a hydrothermal separator (8) via a heat recovery unit (7). The heat recovery unit (7) receives cooling water from the hydrothermal separator (8) to absorb heat from the purified gas.

6. The dehydrocarbonization apparatus for producing food-grade carbon dioxide according to claim 4, characterized in that, The second dehydrogenation reactor (6) is connected to the heat exchanger (4), and the second dehydrogenation reactor (6) provides the purified gas to the heat exchanger (4) for preheating the raw material gas.

7. The dehydrocarbonization apparatus for producing food-grade carbon dioxide according to claim 5, characterized in that, The outlet of the second dehydrocarbonization reactor (6) is also equipped with an oxygen analyzer (11), which is used to determine whether the dehydrocarbonization reaction has been carried out sufficiently.

8. The dehydrocarbonization apparatus for producing food-grade carbon dioxide according to claim 5, characterized in that, Each of the heat recovery units (7) is specifically either a forced circulation heat exchanger or a thermosiphon heat exchanger.

9. The dehydrocarbonization apparatus for producing food-grade carbon dioxide according to claim 4, characterized in that, The heat exchanger (4) is connected to the cooler (12), which is used to condense the water vapor in the purified gas.

10. The dehydrocarbonization apparatus for producing food-grade carbon dioxide according to claim 4, characterized in that, A dehydrogenation electric heater (5) is connected between the heat exchanger (4) and the first dehydrogenation reactor (1), the dehydrogenation electric heater (5) being used to heat the raw material gas to a specified reaction temperature.

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