Coal-to-olefin propylene refrigeration system
By using two sets of propylene compressor units to run in parallel in the propylene refrigeration unit and optimizing the system cooling capacity and feeding method, the problem of poor heat exchange effect of propylene cooler and condenser is solved, reducing system energy consumption and maintenance costs, as well as improving stability and long-term operation capabilities.
Patent Information
- Application Number
- CN202420655518.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-04-01
- Publication Date
- 2025-03-04
- Estimated Expiration
- 2034-04-01
AI Technical Summary
The propylene cooler and condenser of the propylene refrigeration unit are prone to scale and blockage due to the low water pressure and slow flow rate, and poor heat exchange effect, which leads to the increase in the outlet pressure and temperature of the propylene compressor unit, frequent over-temperature and over-pressure problems, and long maintenance cycle.
Two sets of acrylic compressor units are used to operate in parallel. By adding series pipelines and valves, the system cooling capacity and feeding method are optimized, heat exchangers made of stainless steel materials are used, and pipeline pumps are installed on the circulating water pipeline to increase water pressure.
It effectively solves the problem of poor heat exchange effect of propylene cooler and condenser, reduces the outlet pressure and temperature of the propylene compressor unit, reduces the system's operating energy consumption and maintenance costs, and improves the system's stability and long-term operation capabilities.
Smart Images
Figure CN222560301U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of propylene refrigeration, in particular to a coal-to-olefin propylene refrigeration system. Background Art
[0002] The outlet of the propylene compressor of the propylene refrigeration unit is equipped with two water-cooled heat exchangers in series, namely the propylene cooler and the propylene condenser. Because the propylene cooler and condenser of the propylene compressor unit are located at the end of the circulating water network, the water pressure is low, the flow rate is slow, and scaling and blockage are prone to occur, resulting in poor heat exchange effect, which causes the outlet pressure and outlet temperature of the propylene compressor unit to increase. Every year, during high temperature weather, the system load is reduced due to over-temperature and over-pressure at the outlet of the propylene compressor. If the heat exchanger needs to be repaired or cleaned, it must be shut down and replaced before it can be operated, and the maintenance cycle is long. Therefore, the unit system needs to be optimized. Utility Model Content
[0003] The utility model aims to overcome the problems in the prior art and provides a coal-to-olefin propylene refrigeration system.
[0004] A coal-to-olefin propylene refrigeration system comprises a first propylene compressor unit and a second propylene compressor unit, wherein the first propylene compressor unit is used to provide cooling capacity for low-temperature methanol washing A, and the second propylene compressor unit is used to provide cooling capacity for low-temperature methanol washing B; the first propylene compressor unit and the second propylene compressor unit both comprise an inlet separator and a propylene supercooler, a first series pipeline is added between a pipeline before the inlet separator stop valve of the first propylene compressor unit and a pipeline before the inlet separator stop valve from the second propylene compressor unit; a second series pipeline is added between a pipeline after the propylene supercooler outlet valve of the first propylene compressor unit and a pipeline after the propylene supercooler outlet valve of the second propylene compressor unit; valves are also provided on the first series pipeline and the second series pipeline.
[0005] Preferably, the second series pipeline is also connected to the condensing system of the VOCs treatment device in the tank area to provide cooling capacity.
[0006] Preferably, the second series pipeline is also connected to the desulfurization propylene cooler and the ammonia propylene cooler of the gasification and ammonia evaporation device to provide cooling capacity.
[0007] Preferably, the condensation system of the tank area VOCs treatment device is also connected to the first series pipeline.
[0008] Preferably, the desulfurization propylene cooler and the ammonia propylene cooler of the gasification and ammonia evaporation device are also connected to the first series pipeline.
[0009] Preferably, the first series pipeline and the second series pipeline are both provided with an isolation blind plate.
[0010] Preferably, the propylene compressor of the first propylene compressor group and the propylene compressor of the second propylene compressor group are both connected to the control system signal.
[0011] Preferably, the first propylene compressor unit and the second propylene compressor unit further include a propylene cooler and a propylene condenser, and the propylene cooler and the propylene condenser are made of stainless steel.
[0012] Preferably, a pipeline pump is provided on the water supply pipelines of the propylene cooler and the propylene condenser.
[0013] Compared with the prior art, the beneficial effects of the utility model are as follows: the coal-to-olefin propylene refrigeration system of the utility model utilizes two sets of propylene compressor unit refrigeration systems, changes the independent refrigeration system into parallel operation, and continuously optimizes the system cooling capacity and feeding mode, ensuring that cooling capacity is provided for low-temperature methanol washing while providing efficient cooling capacity for the newly added VOCs environmental protection device in the tank area, and using propylene to replace the original design compressor refrigeration process, thereby reducing the system operation energy consumption and maintenance costs; at the same time, sufficient cooling capacity is provided for the newly added ammonia desulfurization refining device and ammonia evaporation system for gasification, reducing the ammonia nitrogen in the gasification wastewater, and improving the impact on subsequent sewage treatment. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Figure 1 The structure of the utility model is shown in FIG. Figure 1 ;
[0015] Figure 2 The structure of the utility model is shown in FIG. Figure 2 ;
[0016] Figure 3 The structure of the utility model is shown in FIG. Figure 3 . DETAILED DESCRIPTION
[0017] In order to make the purpose, technical solution and advantages of the embodiments of the present disclosure clearer, the technical solution of the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings of the embodiments of the present disclosure. Obviously, the described embodiments are part of the embodiments of the present disclosure, not all of the embodiments. Based on the described embodiments of the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.
[0018] Unless otherwise defined, the technical terms or scientific terms used herein shall have the usual meanings understood by persons of ordinary skill in the field to which the present disclosure belongs. The words "first", "second" and similar words used in the patent application specification and claims of the present disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. Words such as "include" or "comprise" and the like mean that the elements or objects appearing before "include" or "comprise" include the elements or objects listed after "include" or "comprise" and their equivalents, and do not exclude other elements or objects. Words such as "connect" or "connected" and the like are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.
[0019] To ensure that the propylene compressor unit can provide sufficient cooling capacity for the low-temperature methanol washing system, the propylene cooler and propylene condenser of the propylene compressor unit are shut down for cleaning every year. To ensure the safe handover and maintenance of the heat exchanger, the system needs to be completely isolated and replaced. A large amount of propylene gas needs to be discharged into the flare during each maintenance, which increases the company's operating costs. According to statistics, the company's methanol production was affected by more than 600 tons this summer due to the restricted operation of the propylene compressor unit. At the same time, the emission of propylene gas due to shutdown for maintenance has increased the company's environmental protection pressure.
[0020] Since the propylene gas at the outlet of the propylene compressor enters the propylene cooler and the propylene condenser in turn, in order to solve the problem that the water pressure on the propylene cooler and the propylene condenser is low, the flow rate is slow, scaling and clogging are prone to occur, the heat exchange effect is poor, and the outlet pressure and outlet temperature of the propylene compressor unit are increased, this embodiment also adopts the method of adding a pipeline pump to the circulating water supply pipeline of the original heat exchanger to increase the circulating water supply pressure, and replaces the original carbon steel heat exchanger with a stainless steel heat exchanger. By increasing the water supply pressure, scaling and clogging are reduced, the heat exchange effect is improved, the outlet pressure of the propylene compressor is reduced, and the outlet temperature of the propylene compressor is reduced, so that the propylene condenser can increase sufficient condensate, and the condensate enters the propylene supercooler. The propylene liquid cooled by the propylene supercooler provides cooling capacity for other systems.
[0021] At the same time, the present invention also realizes the free distribution of the load of the two units by optimizing the process line of the propylene compressor unit and upgrading the control system, which greatly reduces the steam consumption of the units, reduces the start-up and shutdown and heat exchanger inspection and maintenance costs, ensures the stability of the low-temperature methanol washing device and the company's long-term operation, provides sufficient cooling capacity for the company's two new devices, reduces the company's comprehensive product energy consumption and new project costs, and reduces the workload of operators.
[0022] like Figure 1As shown, the coal-to-olefin propylene refrigeration system of this embodiment includes a first propylene compressor unit (also referred to as 1# propylene compressor unit) and a second propylene compressor unit (also referred to as 2# propylene compressor unit), wherein the first propylene compressor unit is used to provide cooling capacity for low-temperature methanol washing A, and the second propylene compressor unit is used to provide cooling capacity for low-temperature methanol washing B; the first propylene compressor unit and the second propylene compressor unit both include an inlet separator 1 and a propylene supercooler 2, a first series pipeline 3 is added between the pipeline before the stop valve of the inlet separator 1 of the first propylene compressor unit and the pipeline before the stop valve of the inlet separator 1 from the second propylene compressor unit, and the first propylene compressor unit from the first propylene compressor unit is connected to the second propylene compressor unit. A series pipeline is added between the pipeline before the stop valve of the inlet separator 1 of the propylene compressor unit and the pipeline before the stop valve of the inlet separator 1 from the second propylene compressor unit, and the series pipeline is added to replace the flare pipeline and the nitrogen filling replacement pipeline; a second series pipeline 4 is added between the pipeline after the outlet valve of the propylene supercooler 2 of the first propylene compressor unit and the pipeline after the outlet valve of the propylene supercooler 2 of the second propylene compressor unit; a series pipeline is added between the pipeline after the outlet valve of the propylene supercooler of the first propylene compressor unit and the pipeline after the outlet valve of the propylene supercooler of the second propylene compressor unit, and the series pipeline is added to replace the flare pipeline and the nitrogen filling replacement pipeline; valves 5 are also provided on the first series pipeline 3 and the second series pipeline 4. The purpose is to facilitate the effective isolation of the two systems.
[0023] As a preferred method, Figure 2 As shown, the second series pipeline 4 is also connected to the condensing system of the tank area VOCs treatment device to provide cooling capacity. As a preferred embodiment, the condensing system of the tank area VOCs treatment device is also connected to the first series pipeline 3.
[0024] In this embodiment, liquid propylene is introduced into the second-stage cold field and refrigerant plate exchanger of the condensation system of the tank area VOCs treatment device on the propylene compressor outlet series pipeline of the first propylene compressor unit and the second propylene compressor unit, with the purpose of using the cold capacity of the liquid propylene itself to reduce the temperature of the secondary cold field and the refrigerant plate exchanger to the temperature required by the process. The liquid propylene after heat exchange is returned to the series pipeline 3 before the inlet separator 1 of the first propylene compressor unit and the second propylene compressor unit in gaseous form for recycling.
[0025] As a preferred method, Figure 3 As shown, the second series pipeline 4 is also connected to the desulfurization propylene cooler and the ammonia propylene cooler of the gasification ammonia evaporation device to provide cooling capacity. As a preferred embodiment, the desulfurization propylene cooler and the ammonia propylene cooler of the gasification ammonia evaporation device are also connected to the first series pipeline 3.
[0026] In this embodiment, liquid propylene is introduced into the gasification device through the series pipeline 4 at the outlet of the propylene compressors of the first propylene compressor unit and the second propylene compressor unit, and a desulfurization propylene cooler and an ammonia water propylene cooler are added to the ammonia distillation system. The purpose is to use the cooling capacity of the liquid propylene itself to reduce the temperature of the ammonia water in the two systems, and then the propylene is returned to the series pipeline 3 before the inlet separator 1 of the first propylene compressor unit and the second propylene compressor unit in gaseous form for recycling.
[0027] This embodiment utilizes two sets of propylene compressor unit refrigeration systems, changes the independent refrigeration system into parallel operation, and continuously optimizes the system cooling capacity and feeding method, ensuring that cooling capacity is provided for low-temperature methanol washing while providing efficient cooling capacity for the newly added VOCs environmental protection device in the tank area, and using propylene to replace the original design compressor refrigeration process to reduce system operation energy consumption and maintenance costs; at the same time, sufficient cooling capacity is provided for the newly added ammonia desulfurization and refining device and ammonia evaporation system for gasification, reducing the ammonia nitrogen in the gasification wastewater and improving the impact on subsequent sewage treatment.
[0028] As a preferred embodiment, the first series pipeline 3 and the second series pipeline 4 are both provided with an isolation blind plate, and the isolation blind plate and the isolation valve form two isolations to ensure the isolation effect.
[0029] As a more preferred embodiment, the propylene compressor of the first propylene compressor group and the propylene compressor of the second propylene compressor group are both connected to the control system signal. The operation of the propylene compressor is controlled by the control system to achieve the purpose of automatic control. The load control of the first propylene compressor group and the second propylene compressor group can be optimized to decouple the compressor speed, the compressor outlet flow, and the surge valve opening from each other, thus achieving a fully automatic mode in a true sense.
[0030] The technical solution of this embodiment effectively solves the difficulty that a single compressor unit corresponds to a single low-temperature methanol washing device and cannot achieve effective energy utilization.
[0031] It can provide efficient cooling capacity for the VOCs device in the tank area, improve absorption efficiency, reduce the operating pressure of the refrigeration system, and reduce safety hazards in the operation of the device.
[0032] Through optimization, the unit's steam consumption can be reduced by approximately 14,400 tons per year, and electricity costs can be saved by approximately 1.008 million kWh per year, while ensuring the long-term stable operation of the system.
[0033] The propylene compressors of the first propylene compressor unit and the second propylene compressor unit are decoupled and controlled from each other, thus achieving a truly fully automatic mode, reducing operating pressure on personnel and reducing the occurrence of man-made accidents.
[0034] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.
Claims
1. A coal-to-olefin propylene refrigeration system, comprising a first propylene compressor unit and a second propylene compressor unit, wherein the first propylene compressor unit is used to provide cooling capacity for low-temperature methanol washing A, and the second propylene compressor unit is used to provide cooling capacity for low-temperature methanol washing B; the first propylene compressor unit and the second propylene compressor unit both comprise an inlet separator (1) and a propylene subcooler (2), characterized in that: A first series pipeline (3) is added between the pipeline before the stop valve of the inlet separator (1) of the first propylene compressor unit and the pipeline before the stop valve of the inlet separator (1) from the second propylene compressor unit; a second series pipeline (4) is added between the pipeline after the outlet valve of the propylene supercooler (2) of the first propylene compressor unit and the pipeline after the outlet valve of the propylene supercooler (2) of the second propylene compressor unit; and valves (5) are also provided on the first series pipeline (3) and the second series pipeline (4).
2. The coal-to-olefin propylene refrigeration system according to claim 1, characterized in that: The second series pipeline (4) is also connected to the condensation system of the VOCs treatment device in the tank area to provide cooling capacity.
3. The coal-to-olefin propylene refrigeration system according to claim 2, characterized in that: The condensation system of the tank area VOCs treatment device is also connected to the first series pipeline (3).
4. The coal-to-olefin propylene refrigeration system according to claim 1, characterized in that: The second series pipeline (4) is also connected to the desulfurization propylene cooler and the ammonia water propylene cooler of the gasification and ammonia evaporation device to provide cooling capacity.
5. The coal-to-olefin propylene refrigeration system according to claim 4, characterized in that: The desulfurization propylene cooler and the ammonia propylene cooler of the gasification and ammonia evaporation device are also connected to the first series pipeline (3).
6. The coal-to-olefin propylene refrigeration system according to claim 1, characterized in that: The first series pipeline (3) and the second series pipeline (4) are both provided with an isolation blind plate.
7. The coal-to-olefin propylene refrigeration system according to claim 1, characterized in that: The propylene compressor of the first propylene compressor group and the propylene compressor of the second propylene compressor group are both connected to the control system signal.
8. The coal-to-olefin propylene refrigeration system according to claim 1, characterized in that: The first propylene compressor unit and the second propylene compressor unit further include a propylene cooler and a propylene condenser, and the propylene cooler and the propylene condenser are made of stainless steel.
9. The coal-to-olefin propylene refrigeration system according to claim 8, characterized in that: A pipeline pump is arranged on the water supply pipelines of the propylene cooler and the propylene condenser.