Hydrogenation of petroleum to produce a hot co-processed liquefied petroleum gas device and system

Abstract

The utility model relates to liquefied petroleum gas technical field discloses a kind of petroleum hydrogenation preparation liquefied petroleum gas heat synergism device and system. The heat synergism device includes high-temperature heat exchanger, heat accumulator and medium-temperature PCM storage tank, and the petroleum hydrogenation preparation liquefied petroleum gas system includes: reaction system and energy storage system;Between the reaction system and energy storage system, it is communicated by multichannel pipeline;The reaction system includes: raw material pretreatment device, hydrogenation device, fractionating device and desulfurization device, and the energy storage system includes: petroleum hydrogenation preparation liquefied petroleum gas heat synergism device and liquefaction and energy storage device;The liquefaction and energy storage device includes compressor set cooler, low-temperature PCM storage tank, condenser.The utility model passes through the heat exchange pipeline between reaction system and energy storage system, systematically solves the problem of low waste heat utilization rate, energy supply and demand imbalance and high carbon emission in LPG preparation, realizes the efficient use effect of energy in liquefied petroleum gas preparation process.

Description

Technical Field

[0001] This utility model belongs to the technical field of liquefied petroleum gas, specifically relating to a thermal synergistic device and system for producing liquefied petroleum gas by petroleum hydrogenation. Background Technology

[0002] Liquefied petroleum gas (LPG) is a mixture of light hydrocarbons produced during petroleum refining, primarily composed of propane and butane. Globally, approximately one-third of LPG comes from refinery byproducts. However, the comprehensive utilization of heat generated during the LPG production process from refinery byproducts has long been a pressing issue. For example, the fractionation towers and desulfurization units in LPG production generate significant amounts of low-grade waste heat at temperatures of 80-200°C, which traditional heat exchangers struggle to efficiently recover. The liquefaction stage requires external steam or electric heating, leading to high carbon emissions. These factors hinder the sustainable and efficient utilization of energy in LPG and its large-scale low-carbon development. By adopting energy-saving technologies, optimizing process flows, and improving equipment operating efficiency, overall process energy consumption can be effectively reduced.

[0003] Patent CN 211346441 U discloses a liquefied petroleum gas water-cooled heat exchanger. This utility model includes an exchanger body and a condenser. By fixing flow regulating valves on both the liquefied petroleum gas inlet and the cold water inlet, the flow rate inside the flow pipe can be controlled in real time according to the needs, and the flow rate can be quickly adjusted to increase the contact area between the two liquids, thereby increasing the heat transfer efficiency.

[0004] Patent CN 205425500 U discloses a solar thermal pump gasification liquefied petroleum gas system. By connecting a first condenser and a second condenser in parallel, along with a hot water storage tank and a phase change thermal storage device, the annual operating time of the direct expansion solar thermal pump is increased, making full use of solar energy and reducing the operating time and energy consumption of auxiliary heat sources.

[0005] Existing technologies mainly suffer from low efficiency in recovering waste heat from medium and low-grade gases, fragmented system thermal management, insufficient energy cascade utilization, and mismatch between process fluctuations and energy supply and demand. Efficient energy utilization in the liquefied petroleum gas (LPG) preparation process remains key to energy conservation in the preparation of liquid hydrocarbon mixtures, especially in terms of system thermal management. This process must reduce production energy consumption and costs while also minimizing carbon emissions, thus contributing to environmental sustainability. Summary of the Invention

[0006] To address the shortcomings of existing technologies, this invention provides a thermal synergy device and system for petroleum hydrogenation to liquefied petroleum gas (LPG). Through heat exchange pipelines between the reaction system and the energy storage system, heat management is implemented to achieve efficient energy utilization during the LPG production process.

[0007] To achieve the goal of efficient energy utilization in the above-mentioned liquefied petroleum gas preparation process, this utility model provides the following technical solution: A thermal co-processing device and system for petroleum hydrogenation to liquefied petroleum gas, the device comprising a high-temperature heat exchanger, a regenerative heat exchanger and a medium-temperature PCM storage tank, wherein the tube-side outlet of the high-temperature heat exchanger is connected to the tube-side inlet of the regenerative heat exchanger. The heat exchanger is equipped with a medium-temperature PCM heat storage tube, the medium-temperature PCM storage tank is equipped with a phase change material inlet and outlet, the medium-temperature PCM heat storage tube is equipped with a phase change material inlet and outlet, the two are interconnected, and the medium-temperature PCM storage tank is connected to a steam pipe.

[0008] Furthermore, the thermal synergy device also includes a steam turbine and a generator, wherein the steam pipe outlet and the steam turbine inlet are connected by a pipeline, and the generator is connected to the steam turbine 4 by a coupling.

[0009] Furthermore, the system includes a reaction system and an energy storage system, which are connected by a pipeline. The energy storage system includes the petroleum hydrogenation to liquefied petroleum gas thermal co-processing device.

[0010] Furthermore, the reaction system includes: a raw material pretreatment device, a hydrogenation device, and a fractionation device. The inlet of the raw material pretreatment device is connected to an external oil delivery pipeline, the outlet of the raw material pretreatment device is connected to the inlet of the hydrogenation device via a pipeline, and the outlet of the hydrogenation device is connected to the inlet of the fractionation device via a pipeline. The reaction system also includes a desulfurization unit, the inlet of which is connected to the outlet of the fractionation unit via a top gas desulfurization pipeline.

[0011] Furthermore, the energy storage system includes: the petroleum hydrogenation to liquefy petroleum gas thermal co-production device and the liquefaction and energy storage device, wherein the petroleum gas outlet of the desulfurization device and the petroleum gas inlet of the liquefaction and cold storage device are connected by pipelines.

[0012] Furthermore, the tube-side inlet of the high-temperature heat exchanger is connected to the outlet of the hydrogenation unit via a pipeline; the tube-side outlet of the regenerative heat exchanger in the petroleum hydrogenation to liquefied petroleum gas thermal synergy unit is connected to the inlet of the hydrogenation unit via a pipeline; the shell-side inlet of the high-temperature heat exchanger is connected to the outlet of the fractionation unit via a top gas desulfurization pipeline; the shell-side outlet of the high-temperature heat exchanger is connected to the inlet of the raw material pretreatment unit via a top gas diversion pipeline; the top gas inlet of the desulfurization unit is connected to the top gas outlet of the fractionation unit via a top gas desulfurization pipeline; the shell-side inlet of the regenerative heat exchanger is connected to the desulfurization wastewater outlet of the desulfurization unit via a pipeline; and the shell-side outlet of the regenerative heat exchanger is connected to the desulfurization wastewater inlet of the desulfurization unit via a pipeline.

[0013] Furthermore, the liquefaction and energy storage device includes a compressor cooler, the inlet of which is connected to the outlet of the desulfurization device via a pipeline.

[0014] Furthermore, the liquefaction and cold storage device also includes: a cryogenic PCM storage tank, which is provided with a cold working fluid inlet and outlet, and the compressor unit cooler is provided with another set of cold working fluid inlet and outlet, with the outlets and inlets of the two connected by cross-connecting pipelines.

[0015] Furthermore, the liquefaction and energy storage device also includes a condenser, wherein the cold outlet of the compressor unit cooler is connected to the cold inlet of the condenser via a pipeline, and the condenser outlet is provided with a liquefied petroleum gas delivery pipeline.

[0016] Compared with existing technologies, this utility model provides a thermal synergistic device and system for petroleum hydrogenation to liquefied petroleum gas, which has the following beneficial effects: 1. Achieve multi-stage waste heat recovery: the heat released by the hydrogenation unit is used to generate electricity, thereby reducing external electricity demand; the medium-temperature heat after the high-temperature waste heat power generation is used to heat the desulfurization unit; the absorption heat pump raises the waste heat of the 90℃ distillation tower top gas to 150℃ and supplies it to the desulfurization unit; the compressor unit cooler works in conjunction with the low-temperature PCM storage tank to recover liquefied cold energy.

[0017] 2. By interconnecting the heat storage heat exchanger with the pipelines between the storage tanks, integrated management of high and low temperature waste heat exchange and medium temperature waste heat power generation is achieved. This systematically solves the problems of low waste heat utilization, energy supply and demand imbalance, and high carbon emissions in LPG production, realizing full-process optimization of thermal energy with "high quality and high utilization, low quality and high efficiency improvement, and cold energy closed loop," providing an innovative solution for the green transformation of the petroleum hydrogenation to LPG process. Attached Figure Description

[0018] Figure 1 This is a diagram illustrating the composition of the petroleum hydrogenation to liquefied petroleum gas thermal synergistic device according to an embodiment of this utility model. Figure 2 This is a schematic diagram of the thermal synergistic system for petroleum hydrogenation to liquefied petroleum gas, as described in an embodiment of this utility model.

[0019] Figure 3 This is a system composition diagram of the liquefaction and cold storage device according to an embodiment of the present invention.

[0020] In the diagram: 1. High-temperature heat exchanger; 2. Regenerative heat exchanger; 3. Medium-temperature PCM storage tank; 4. Steam turbine; 5. Generator; 6. Medium-temperature PCM regenerative tube. 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] A thermal co-processing device for petroleum hydrogenation to liquefied petroleum gas (LPG) is described in the attached document. Figure 1 The device includes a high-temperature heat exchanger 1, a heat storage heat exchanger 2, and a medium-temperature PCM storage tank 3. The high-temperature heat exchanger 1 is used for high-temperature heat exchange, and the tube-side outlet of the high-temperature heat exchanger 1 is connected to the tube-side inlet of the heat storage heat exchanger 2 to transport the heat exchanged heat into the heat storage heat exchanger 2 for further heat utilization. The heat storage heat exchanger 2 is used for medium-temperature heat storage and low-temperature heat exchange. The heat storage heat exchanger 2 is equipped with a medium-temperature PCM heat storage tube 6 for storing medium-temperature heat. The heat flow from the high-temperature heat exchanger 1 enters the tube side inlet of the heat storage heat exchanger 2, exchanges heat through the medium-temperature PCM heat storage tube 6, and then the heat flow enters the tube side for low-temperature heat exchange and flows out from the tube side outlet of the heat storage heat exchanger 2. The medium-temperature PCM heat storage tube 6 is equipped with a medium-temperature PCM phase change material. The intermediate-temperature PCM storage tank 3 is provided with a phase change material inlet and outlet, and the intermediate-temperature PCM heat storage pipe 6 is provided with an inlet and outlet. The two are interconnected. After the intermediate-temperature PCM phase change material in the heat storage heat exchanger 2 absorbs heat, it is transported to the intermediate-temperature PCM storage tank 3. The PCM material with a large amount of phase change heat returns to a low-temperature state after heat exchange in the intermediate-temperature PCM storage tank 3, and is transported back to the intermediate-temperature PCM heat storage pipe 6 through the pipeline, thus completing the closed-loop circulation of the intermediate-temperature PCM phase change material.

[0023] The medium-temperature PCM storage tank 3 is connected to a steam pipe. The medium-temperature PCM storage tank 3 is used to generate medium-temperature steam by utilizing the heat stored in the medium-temperature PCM heat storage tube 6 of the medium-temperature PCM phase change material. The inlet of the steam pipe is connected to demineralized water. After entering the storage tank, the demineralized water absorbs the phase change heat of the PCM material and evaporates into medium-temperature steam, which flows out through the outlet of the steam pipe.

[0024] The petroleum hydrogenation to liquefied petroleum gas thermal co-processing unit further includes: a steam turbine 4 and a generator 5. The steam pipe outlet and the steam turbine 4 inlet are connected by a pipeline. The steam turbine 4 is used for... Converting the thermal energy of steam into rotating machinery Yes, steam enters turbine 4 through the inlet, expands in the nozzles, decreases pressure, increases velocity, and transfers heat energy. The energy is converted into mechanical energy that rotates the impeller shaft; The generator 5 is connected to the steam turbine 4 via a coupling. The mechanical energy generated by the steam turbine 4 is transmitted to the generator 5 through the coupling to generate electricity. The generator 5 is also equipped with a power transmission pipeline.

[0025] The aforementioned thermal synergy device enables the cascade utilization of energy in the petroleum hydrogenation to LPG production process. Based on the original high and low temperature heat exchange, it stores medium-temperature heat and uses it for power generation, solving the problem of the difficulty in utilizing medium-temperature heat in this production process and providing an innovative solution for the green transformation of the petroleum hydrogenation to LPG process.

[0026] Please see the appendix Figure 2 A thermal co-processing system for petroleum hydrogenation to liquefied petroleum gas (LPG) is disclosed. The system includes a reaction system and an energy storage system. The reaction system and the energy storage system are connected by a pipeline for heat management. The energy storage system includes the thermal co-processing device for petroleum hydrogenation to LPG. The energy storage system absorbs heat of different grades from the reaction system, and then utilizes or improves the grade of the heat before returning it to the reaction system to supply heat to the reaction system.

[0027] The reaction system includes a raw material pretreatment unit, a hydrogenation unit, and a fractionation unit. The inlet of the raw material pretreatment unit is connected to an external petroleum pipeline for removing harmful impurities from the petroleum and adjusting the raw material to meet the specifications for the hydrogenation reaction. The outlet of the raw material pretreatment unit is connected to the inlet of the hydrogenation unit via a pipeline for transporting the treated petroleum from the pretreatment unit to the hydrogenation unit for further reaction. The hydrogenation unit is connected to an external hydrogen pipeline for supplying hydrogen to the reaction. The outlet of the hydrogenation unit is connected to the inlet of the fractionation unit via a pipeline for transporting the hydrogenation product to the fractionation unit. The fractionation unit is used for separating the petroleum hydrogenation product. After the product gas from the hydrogenation unit is separated by the fractionation unit, the overhead gas from the top of the fractionation tower flows out through an overhead gas pipeline. The reaction system also includes a desulfurization device, the inlet of which is connected to the outlet of the fractionation device via a top gas desulfurization pipeline. The desulfurization device is used to receive the top gas from the fractionation tower that needs to be desulfurized, and to further remove sulfur from the petroleum gas.

[0028] The energy storage system includes: the petroleum hydrogenation to liquefied petroleum gas thermal co-processing device and the liquefaction and energy storage device. The inlet of the high-temperature heat exchanger 1 is connected to the outlet of the hydrogenation device via a pipeline, and is used to receive the high-temperature heat flow from the hydrogenation device for heat exchange. The outlet of the heat storage heat exchanger 2 of the petroleum hydrogenation to liquefied petroleum gas thermal co-processing device is connected to the inlet of the hydrogenation device via a pipeline, and is used to transport the heat-exchanged material back to the hydrogenation device to continue to participate in the hydrogenation reaction to generate petroleum gas products.

[0029] The shell-side inlet of the high-temperature heat exchanger 1 is connected to the outlet of the fractionation unit via a top gas desulfurization pipeline, which is used to receive a portion of the top fractionated gas that needs to be heated; the shell-side outlet of the high-temperature heat exchanger 1 is connected to the inlet of the raw material pretreatment unit via a top gas diversion pipeline, which is used to provide the heated top fractionated gas to the raw material pretreatment unit. The desulfurization unit's overhead gas inlet and the fractionation unit's overhead gas outlet are connected via an overhead gas desulfurization pipeline for desulfurizing the overhead gas from the fractionation unit that requires desulfurization. The overhead gas desulfurization pipeline is also connected to an overhead gas diversion pipeline for diverting the overhead gas from the fractionation unit. Part of the overhead gas enters the desulfurization unit via the overhead gas desulfurization pipeline; the remaining overhead gas enters the heat storage unit via the overhead gas diversion pipeline. After improving the calorific quality of this portion of the overhead gas, it enters the feedstock pretreatment pipeline via the connection between the heat storage unit and the feedstock pretreatment unit, proceeding to the feedstock pretreatment unit for reaction and feedstock preheating. Incompletely reacted overhead gas can be recycled back to the feedstock pretreatment unit for further reaction to improve the reaction conversion rate. The heavy fraction oil flows out from the bottom of the fractionation unit via a pipeline.

[0030] The shell-side inlet of the heat storage heat exchanger 2 is connected to the outlet of the desulfurization device via a pipeline, and is used to receive desulfurization wastewater from the desulfurization device; after being heated by the medium-temperature PCM heat storage tube 6, the shell-side outlet of the heat storage heat exchanger 2 is connected to the inlet of the desulfurization device via a pipeline, and is used to transport the desulfurization wastewater after heat absorption back to the desulfurization device.

[0031] The desulfurization unit's liquefaction gas outlet and the liquefaction and cold storage unit's liquefaction gas inlet are connected by a pipeline. The liquefaction and cold storage unit is used to cool the liquefaction gas product, and its outlet is equipped with a liquefaction gas delivery pipeline for product transportation.

[0032] Please see the appendix Figure 3 The liquefaction and cold storage device is used to cool petroleum gas to obtain the final liquefied petroleum gas; the liquefaction and cold storage device includes a compressor unit cooler, a cryogenic PCM storage tank, and a condenser.

[0033] The compressor cooler inlet is connected to the desulfurization unit outlet via a pipeline. The compressor cooler is used to receive liquefied petroleum gas products from the desulfurization unit, cool the liquefied petroleum gas, and increase the gas pressure so that it can be liquefied at room temperature or a lower temperature. The compressor cooler cold outlet is connected to the condenser cold inlet via a pipeline. The condenser is used for liquefied petroleum gas. The condenser outlet is equipped with a liquefied petroleum gas delivery pipeline. After the liquefied petroleum gas is cooled and liquefied by the condenser, it is sent to a special storage tank through the liquefied petroleum gas delivery pipeline.

[0034] The compressor unit cooler is equipped with another set of refrigerant inlets and outlets, and the cryogenic PCM storage tank is equipped with refrigerant inlets and outlets. The outlets and inlets of the two are connected by cross-connecting pipes to store the residual cooling capacity generated by the compressor unit cooler and to replenish the cooling capacity in a timely manner when the temperature of the liquefied petroleum gas fluctuates greatly, so as to reduce the demand for external energy.

[0035] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0036] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A thermal co-processing device for petroleum hydrogenation to liquefied petroleum gas, characterized in that: The heat exchanger includes a high-temperature heat exchanger (1), a heat storage heat exchanger (2), and a medium-temperature PCM storage tank (3). The tube outlet of the high-temperature heat exchanger (1) is connected to the tube inlet of the heat storage heat exchanger (2). The heat storage heat exchanger (2) is equipped with a medium-temperature PCM heat storage tube (6). The medium-temperature PCM storage tank (3) is equipped with a phase change material inlet and outlet. The medium-temperature PCM heat storage tube (6) is equipped with a phase change material inlet and outlet. The two are cross-connected. The medium-temperature PCM storage tank (3) is connected to a steam pipe.

2. The petroleum hydrogenation to liquefied petroleum gas thermal co-processing device according to claim 1, characterized in that: The thermal coordination device also includes a steam turbine (4), and the steam pipe is connected to the inlet of the steam turbine (4) through a pipeline.

3. The petroleum hydrogenation to liquefied petroleum gas thermal co-processing device according to claim 2, characterized in that: The thermal synergy device further includes a generator (5), which is connected to the steam turbine (4) via a coupling.

4. A petroleum hydrogenation to liquefied petroleum gas (LPG) thermal co-processing system, said system being implemented based on the petroleum hydrogenation to LPG thermal co-processing device according to any one of claims 1 to 3, characterized in that: The system includes a reaction system and an energy storage system, which are connected by a pipeline. The energy storage system includes the petroleum hydrogenation to liquefied petroleum gas thermal co-processing device.

5. The petroleum hydrogenation to liquefied petroleum gas thermal synergy system according to claim 4, characterized in that: The reaction system includes: a raw material pretreatment unit, a hydrogenation unit, and a fractionation unit. The inlet of the raw material pretreatment unit is connected to an external oil transportation pipeline, and the outlet of the raw material pretreatment unit is connected to the inlet of the hydrogenation unit via a pipeline. The outlet of the hydrogenation unit is connected to the inlet of the fractionation unit via a pipeline. The reaction system also includes: a desulfurization unit, and the inlet of the desulfurization unit is connected to the outlet of the fractionation unit via a top gas desulfurization pipeline.

6. The petroleum hydrogenation to liquefied petroleum gas thermal synergy system according to claim 5, characterized in that: The energy storage system includes: the petroleum hydrogenation to liquefy petroleum gas thermal co-production device and the liquefaction and cold storage device, wherein the petroleum gas outlet of the desulfurization device and the petroleum gas inlet of the liquefaction and cold energy device are connected by a pipeline.

7. The petroleum hydrogenation to liquefied petroleum gas thermal synergy system according to claim 5, characterized in that: The tube side inlet of the high-temperature heat exchanger (1) is connected to the outlet of the hydrogenation unit via a pipeline. The tube side outlet of the thermal storage heat exchanger (2) of the petroleum hydrogenation to liquefied petroleum gas co-processing unit is connected to the inlet of the hydrogenation unit via a pipeline. The shell side inlet of the high-temperature heat exchanger (1) is connected to the outlet of the fractionation unit via a top gas desulfurization pipeline. The shell side outlet of the high-temperature heat exchanger (1) is connected to the inlet of the raw material pretreatment unit via a top gas diversion pipeline. The top gas inlet of the desulfurization unit is connected to the top gas outlet of the fractionation unit via a top gas desulfurization pipeline. The shell side inlet of the thermal storage heat exchanger (2) is connected to the desulfurization wastewater outlet of the desulfurization unit via a pipeline. The shell side outlet of the thermal storage heat exchanger (2) is connected to the desulfurization wastewater inlet of the desulfurization unit via a pipeline.

8. The petroleum hydrogenation to liquefied petroleum gas thermal synergy system according to claim 6, characterized in that: The liquefaction and cooling device includes a compressor cooler, the inlet of which is connected to the outlet of the desulfurization device via a pipeline.

9. The petroleum hydrogenation to liquefied petroleum gas thermal synergy system according to claim 8, characterized in that: The liquefaction and cold storage device also includes a cryogenic PCM storage tank, which is provided with a cold working fluid inlet and outlet, and the compressor unit cooler is provided with another set of cold working fluid inlet and outlet, with the outlets and inlets of the two connected by pipelines.

10. The petroleum hydrogenation to liquefied petroleum gas thermal synergy system according to claim 8, characterized in that: The liquefaction and cold storage device further includes a condenser, wherein the cold outlet of the compressor unit cooler is connected to the cold inlet of the condenser via a pipeline, and the outlet of the condenser is provided with a liquefied petroleum gas delivery pipeline.

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