High-efficiency steam regulation and distribution device for ammonia synthesis system

Abstract

This utility model relates to the field of steam regulation and distribution technology, and is a high-efficiency steam regulation and distribution device for an ammonia synthesis system. It includes a first boiler, a second boiler, a third boiler, a desuperheater and pressure reducer, an air separation turbine, an ammonia synthesis turbine, and a medium-pressure user steam network. A first high-pressure steam pipeline connects the third boiler to the air separation turbine; a second high-pressure steam pipeline connects the second boiler to the ammonia synthesis turbine; a first medium-pressure steam pipeline connects the third boiler to the medium-pressure user steam network; a second medium-pressure steam pipeline connects the second high-pressure steam pipeline to the first medium-pressure steam pipeline; and a desuperheater and pressure reducer are connected to the second medium-pressure steam pipeline. This utility model has a reasonable and compact structure, is easy to use, shortens the time and resource consumption for chemical cleaning and steam purging of power steam pipelines, reduces steam transport heat energy loss, and also ensures stable operation of steam-using equipment in the ammonia synthesis system.

Description

Technical Field

[0001] This utility model relates to the field of steam regulation and distribution technology for coal-to-ammonia synthesis, and is a high-efficiency steam regulation and distribution device for ammonia synthesis systems. Background Technology

[0002] With increasingly stringent environmental regulations and dwindling coal resources, the energy-intensive fixed-bed gasification process in the coal-to-ammonia synthesis sector is gradually being replaced by advanced coal-water slurry gasification. A coal chemical company has invested in a green ammonia synthesis process project to replace its existing fixed-bed gasification technology. This project uses coal as raw material and employs advanced internal compression low-temperature air separation, coal-water slurry gasification, sulfur-resistant isothermal shift reaction, and Casarte ammonia synthesis technology. Liquid ammonia is the final product. The nitrogen-hydrogen compressor in the ammonia synthesis unit is driven by 9.8 MPaG steam, and the ammonia refrigeration unit is driven by 4.0 MPaG steam.

[0003] Given the steam demand of the newly built ammonia synthesis unit, the existing boiler steam supply of this coal chemical enterprise faces the following problems:

[0004] First, the chemical cleaning and steam purging of steam pipelines are time-consuming, rely on a single steam source, and result in high steam consumption. Before starting up each steam-using device, the power steam pipeline system requires chemical cleaning and steam purging. Since existing power steam users all use individual pipelines, each steam-using device requires separate chemical cleaning and steam purging of its own pipelines before startup, leading to a very long chemical cleaning and steam purging cycle. Furthermore, steam purging typically employs alternating hot and cold purging methods to accelerate the process. During the pipeline cooling period, this results in a large amount of steam being vented, causing significant steam waste. This results in extremely high commissioning time and costs for the entire project, making it difficult to meet the needs of project construction and production.

[0005] Secondly, the steam pipeline experiences significant temperature drop losses during transport, making it difficult to meet the steam demand of the turbine. Because the ammonia synthesis system and ammonia refrigeration system are located far from the boiler, calculations based on existing steam pipeline resistance and temperature drops show that the resistance drop for 9.8 MPaG and 4.0 MPaG steam transported to these systems is 0.3 MPaG, and the temperature drop is around 35°C. This excessive temperature drop, especially during the initial start-up phase when the load is low and steam consumption is low, leads to an even greater temperature drop, falling below the turbine's steam requirements and failing to meet start-up needs.

[0006] Third, the insufficient steam supply capacity of the existing steam boilers will lead to instability in the overall ammonia synthesis production system. When the ammonia synthesis system and ammonia refrigeration system are far from the steam boilers, the energy loss due to temperature drop during steam pipeline transportation and the unstable steam supply from the steam boilers will result in the quality of ammonia synthesis products falling below normal standards.

[0007] In summary, the high start-up and purging costs of the power steam pipeline system, the large temperature drop during steam transmission, and the unstable boiler steam supply capacity within the synthetic ammonia production system have become pressing technical challenges that enterprises need to address. Summary of the Invention

[0008] This invention provides a high-efficiency steam regulation and distribution device for ammonia synthesis systems, overcoming the shortcomings of the prior art. It can effectively solve the problems of high start-up and purging costs of power steam pipeline systems, large temperature drop during steam transmission, and unstable boiler steam supply capacity in existing ammonia synthesis systems.

[0009] The technical solution of this utility model is achieved through the following measures: a high-efficiency steam regulation and distribution device for a synthetic ammonia system, comprising a first boiler, a second boiler, a third boiler, a desuperheater and pressure reducer, an air separation turbine, an ammonia synthesis turbine, and a medium-pressure user steam network. A first high-pressure steam pipeline is fixedly connected between the outlet of the third boiler and the inlet of the air separation turbine. A second high-pressure steam pipeline is fixedly connected between the outlet of the second boiler and the inlet of the ammonia synthesis turbine. A first medium-pressure steam pipeline is fixedly connected between the outlet of the first boiler and the inlet of the medium-pressure user steam network. A second medium-pressure steam pipeline is fixedly connected between the second high-pressure steam pipeline and the first medium-pressure steam pipeline. A desuperheater and pressure reducer are fixedly connected to the second medium-pressure steam pipeline. A high-pressure steam interconnection pipeline is fixedly connected between the second high-pressure steam pipeline and the first high-pressure steam pipeline.

[0010] The following are further optimizations and / or improvements to the above-mentioned utility model technical solution:

[0011] The above also includes a changeover steam pipeline network and an ammonia refrigeration ice machine, with a first secondary medium-pressure steam pipeline fixedly connected between the outlet of the changeover steam pipeline network and the inlet of the ammonia refrigeration ice machine.

[0012] The above also includes a waste heat boiler, and a second by-product medium-pressure steam pipeline is fixedly connected between the outlet of the waste heat boiler and the first by-product medium-pressure steam pipeline.

[0013] A third medium-pressure steam pipeline is fixedly connected between the second medium-pressure steam pipeline between the outlet of the aforementioned desuperheater and the first medium-pressure steam pipeline, and between the outlet of the conversion steam network and the first by-product medium-pressure steam pipeline.

[0014] Pressure reducing valves and first pressure gauges are fixedly installed sequentially along the medium flow direction on the three medium-pressure steam pipelines mentioned above.

[0015] A first shut-off valve is fixedly installed on the aforementioned high-pressure steam interconnection pipeline.

[0016] A second shut-off valve is fixedly installed on the second medium-pressure steam pipeline between the second high-pressure steam pipeline and the inlet of the desuperheater and pressure reducer.

[0017] A third shut-off valve and a second pressure gauge are fixedly installed sequentially along the medium flow direction on the second medium-pressure steam pipeline between the outlet of the aforementioned desuperheater and the third medium-pressure steam pipeline.

[0018] A third pressure gauge and a fourth shut-off valve are fixedly installed sequentially along the medium flow direction on the second high-pressure steam pipeline between the second boiler outlet and the high-pressure steam interconnection pipeline. A fourth pressure gauge and a fifth shut-off valve are fixedly installed sequentially along the medium flow direction on the first high-pressure steam pipeline between the third boiler outlet and the high-pressure steam interconnection pipeline.

[0019] A fifth pressure gauge is fixedly installed on the first secondary medium-pressure steam pipeline between the outlet of the aforementioned conversion steam pipeline and the third medium-pressure steam pipeline, and a sixth pressure gauge is fixedly installed on the first medium-pressure steam pipeline between the outlet of the first boiler and the second medium-pressure steam pipeline.

[0020] This utility model has a reasonable and compact structure and is easy to use. It uses a desuperheater and pressure reducer to reasonably adjust and distribute the steam of different qualities produced by each boiler, shortening the time and resource consumption of chemical cleaning and steam purging of power steam pipelines, reducing the heat energy loss of steam transportation, and making the steam-using equipment of the ammonia synthesis system operate stably, thereby improving the economic benefits of the enterprise. Attached Figure Description

[0021] Appendix Figure 1 This is a schematic diagram of the process flow of this utility model.

[0022] The codes in the attached diagram are as follows: 1 for the first boiler, 2 for the second boiler, 3 for the third boiler, 4 for the desuperheater and pressure reducer, 5 for the air separation turbine, 6 for the ammonia synthesis turbine, 7 for the medium-pressure user steam network, 8 for the second high-pressure steam pipeline, 9 for the first medium-pressure steam pipeline, 10 for the second medium-pressure steam pipeline, 11 for the high-pressure steam interconnection pipeline, 12 for the shift converter steam network, 13 for the ammonia refrigeration supply ammonia ice machine, 14 for the first by-product medium-pressure steam pipeline, 15 for the second by-product medium-pressure steam pipeline, 16 for the third medium-pressure steam pipeline, 17 for the pressure reducing valve, 18 for the first pressure gauge, 19 for the first shut-off valve, 20 for the second shut-off valve, 21 for the third shut-off valve, 22 for the second pressure gauge, 23 for the third pressure gauge, 24 for the fourth shut-off valve, 25 for the fourth pressure gauge, 26 for the fifth shut-off valve, 27 for the fifth pressure gauge, 28 for the first high-pressure steam pipeline, 29 for the sixth pressure gauge, and 30 for the waste heat boiler. Detailed Implementation

[0023] This utility model is not limited to the following embodiments, and the specific implementation method can be determined according to the technical solution of this utility model and the actual situation.

[0024] Unless otherwise specified, all equipment and devices used in this invention are existing, publicly known, and commonly used equipment and devices in the field.

[0025] In this utility model, for ease of description, the description of the relative positions of the components is based on the appendix to the specification. Figure 1 The layout is described using a diagrammatic method, such as the positional relationships of front, back, top, bottom, left, and right, which are based on the instructions attached. Figure 1 The orientation of the layout is determined by the direction of the map.

[0026] The present invention will be further described below with reference to the embodiments and accompanying drawings:

[0027] Example 1: As shown in the attached document Figure 1 As shown, the high-efficiency steam regulation and distribution device of the ammonia synthesis system includes a first boiler 1, a second boiler 2, a third boiler 3, a desuperheater and pressure reducer 4, an air separation turbine 5, an ammonia synthesis turbine 6, and a medium-pressure user steam network 7. A first high-pressure steam pipeline 28 is fixedly connected between the outlet of the third boiler 3 and the inlet of the air separation turbine 5. A second high-pressure steam pipeline 8 is fixedly connected between the outlet of the second boiler 2 and the inlet of the ammonia synthesis turbine 6. A first medium-pressure steam pipeline 9 is fixedly connected between the outlet of the first boiler 1 and the inlet of the medium-pressure user steam network 7. A second medium-pressure steam pipeline 10 is fixedly connected between the second high-pressure steam pipeline 8 and the first medium-pressure steam pipeline 9. A desuperheater and pressure reducer 4 is fixedly connected to the second medium-pressure steam pipeline 10. A high-pressure steam interconnection pipeline 11 is fixedly connected between the second high-pressure steam pipeline 8 and the first high-pressure steam pipeline 28.

[0028] This invention uses a desuperheater and pressure reducer 4 to rationally regulate and distribute steam of different qualities produced by each boiler, shortening the time and resource consumption for chemical cleaning and steam purging of power steam pipelines, reducing heat energy loss during steam transportation, and ensuring stable operation of steam-using equipment in the ammonia synthesis system, thereby improving the economic benefits of the enterprise.

[0029] As required, the first boiler 1 produces 4.8 MPaG of steam, while the second boiler 2 and the third boiler 3 both produce 9.8 MPaG of steam.

[0030] The desuperheater and pressure reducer 4 adjusts the 9.8MPaG steam to 4.8MPa steam. The desuperheater and pressure reducer 4 can be a steam pipeline desuperheater and pressure reducer device produced by Shandong Xin'ao Machinery Co., Ltd., model XM-WY-2913, which is suitable for cooling and reducing the pressure of high-pressure steam to medium-pressure steam.

[0031] The high-pressure steam produced by the second boiler 2 and the third boiler 3 can be interconnected through the high-pressure steam interconnection pipeline 11 and distributed to other steam-using equipment as needed.

[0032] The steam high-efficiency regulating and distribution device of the above-mentioned ammonia synthesis system can be further optimized and / or improved according to actual needs:

[0033] Example 2: Its difference from Example 1 is as follows: (See attached) Figure 1As shown, the high-efficiency steam regulation and distribution device of the ammonia synthesis system also includes a shift steam network 12 and an ammonia refrigeration ice machine 13. A first by-product medium-pressure steam pipeline 14 is fixedly connected between the outlet of the shift steam network 12 and the inlet of the ammonia refrigeration ice machine 13.

[0034] As needed, the by-product medium-pressure steam output from the steam pipeline network 12 is changed to 4.0 MPaG to provide steam power for the ammonia refrigeration machine 13.

[0035] Example 3: Its difference from Examples 1 to 2 is as follows: (See attached) Figure 1 As shown, it also includes a waste heat boiler 30, and a second by-product medium-pressure steam pipeline 15 is fixedly connected between the outlet of the waste heat boiler 30 and the first by-product medium-pressure steam pipeline 14.

[0036] As needed, the medium-pressure steam output from the waste heat boiler 30 is 4.0 MPaG, which can also provide steam power supply for the ammonia refrigeration unit 13.

[0037] Example 4: Its difference from Examples 1 to 3 is as follows: (See attached) Figure 1 As shown, a third medium-pressure steam pipeline 16 is fixedly connected between the second medium-pressure steam pipeline 10 between the outlet of the desuperheater 4 and the first medium-pressure steam pipeline 9, and the first by-product medium-pressure steam pipeline 14 between the outlet of the conversion steam network 12 and the second by-product medium-pressure steam pipeline 15.

[0038] Example 5: It differs from Examples 1 to 4 in that, as shown in the appendix... Figure 1 As shown, a pressure reducing valve 17 and a first pressure gauge 18 are fixedly installed sequentially along the medium flow direction on the third medium-pressure steam pipeline 16.

[0039] If needed, the 4.8MPaG steam output by the desuperheater and pressure reducer 4 can be further depressurized to 4.0MPaG by the pressure reducing valve 17, which can also provide steam power supply for the ammonia refrigeration machine 13.

[0040] Example 6: Its difference from Examples 1 to 5 is as follows: (See attached) Figure 1 As shown, a first shut-off valve 19 is fixedly installed on the high-pressure steam interconnection pipeline 11.

[0041] Example 7: Its difference from Examples 1 to 6 is as follows: (See attached) Figure 1 As shown, a second shut-off valve 20 is fixedly installed on the second medium-pressure steam pipeline 10 between the second high-pressure steam pipeline 8 and the inlet of the desuperheater 4.

[0042] Example 8: It differs from Examples 1 to 7 in that: as shown in the appendix Figure 1As shown, a third shut-off valve 21 and a second pressure gauge 22 are fixedly installed sequentially along the medium flow direction on the second medium-pressure steam pipeline 10 between the outlet of the desuperheater and pressure reducer 4 and the third medium-pressure steam pipeline 16.

[0043] Example 9: It differs from Examples 1 to 8 in that: as shown in the appendix Figure 1 As shown, a third pressure gauge 23 and a fourth shut-off valve 24 are fixedly installed in sequence along the medium flow direction on the second high-pressure steam pipeline 8 between the outlet of the second boiler 2 and the high-pressure steam interconnection pipeline 11. A fourth pressure gauge 25 and a fifth shut-off valve 26 are fixedly installed in sequence along the medium flow direction on the first high-pressure steam pipeline 28 between the outlet of the third boiler 3 and the high-pressure steam interconnection pipeline 11.

[0044] Example 10: It differs from Examples 1 to 9 in that, as shown in the appendix... Figure 1 As shown, a fifth pressure gauge 27 is fixedly installed on the first secondary medium-pressure steam pipeline 14 between the outlet of the change steam pipeline network 12 and the third medium-pressure steam pipeline 16, and a sixth pressure gauge 29 is fixedly installed on the first medium-pressure steam pipeline 9 between the outlet of the first boiler 1 and the second medium-pressure steam pipeline 10.

[0045] Depending on the needs, the pipelines and equipment of the high-efficiency steam regulation and distribution device of the ammonia synthesis system may also be equipped with conventional valves, thermometers and pressure gauges known in the art, as required by production.

[0046] Before this utility model is put into operation, high-pressure steam pipelines (power pipelines) need to be purged with steam. Through the as-needed opening and closing of the first shut-off valve 19, second shut-off valve 20, fourth shut-off valve 24, and fifth shut-off valve 26, the third boiler 3 produces steam to continuously purge the first high-pressure steam pipeline 28 in a hot state. While this pipeline cools, the third boiler 3 then continuously purges the second high-pressure steam pipeline 8 in a hot state. When this pipeline begins to cool, the third boiler 3 purges the first high-pressure steam pipeline 28 again. This alternating steam purging not only meets the requirements of the high-pressure steam pipeline purging process but also ensures that the third boiler 3 operates under stable conditions for a long period, achieving the requirements for steam purging and steam supply. Moreover, during the cooling period, the steam remaining in the pipeline does not need to be vented, greatly improving the purging efficiency of the entire high-pressure steam pipeline system while minimizing steam resource consumption. Furthermore, if the third boiler 3 malfunctions and is not ready for operation, the second boiler 2 can be used to supply steam for the purging process, ensuring its smooth operation.

[0047] The above technical features constitute various embodiments of this utility model, which have strong adaptability and implementation effect. Unnecessary technical features can be added or removed according to actual needs to meet the needs of different situations.

[0048] The usage process of this utility model embodiment includes:

[0049] S01, the medium-pressure steam produced by the first boiler 1 is transported to the medium-pressure user steam network 7 through the first medium-pressure steam pipeline 9 to provide medium-pressure steam supply for various medium-pressure steam-using equipment;

[0050] S02, the high-pressure steam produced by the second boiler 2 is transported to the ammonia synthesis turbine 6 through the second high-pressure steam pipeline 8 to provide high-pressure steam power for the ammonia synthesis turbine 6;

[0051] S03, the high-pressure steam produced by the third boiler 3 is transported to the air separation turbine 5 through the first high-pressure steam pipeline 28 to provide high-pressure steam power for the air separation turbine 5;

[0052] S04, the by-product medium-pressure steam output from the steam conversion network 12 is transported to the ammonia refrigeration ammonia ice machine 13 through the first by-product medium-pressure steam pipeline 14 to provide medium-pressure steam power for the ammonia refrigeration ammonia ice machine 13;

[0053] S05, the medium-pressure steam output from the waste heat boiler 30 is transported to the ammonia refrigeration ammonia ice machine 13 through the second by-product medium-pressure steam pipeline 15 and the first by-product medium-pressure steam pipeline 14 to supplement the medium-pressure steam power of the ammonia refrigeration ammonia ice machine 13;

[0054] S06, the high-pressure steam produced by the third boiler 3 and the second boiler 2 is cooled and reduced by the desuperheater and pressure reducer 4, and then successively transported to the medium-pressure user steam network 7 through the second medium-pressure steam pipeline 10 and the first medium-pressure steam pipeline 9 to supplement the medium-pressure steam supply for each steam-consuming equipment.

[0055] S07, the high-pressure steam produced by the third boiler 3 and the second boiler 2 is cooled and reduced in pressure by the desuperheater and pressure reducer 4, and can then be transported sequentially to the second medium-pressure steam pipeline 10, the third medium-pressure steam pipeline 16 and the first auxiliary medium-pressure steam pipeline 14 to the ammonia refrigeration ammonia ice machine 13 to provide medium-pressure steam power for the ammonia refrigeration ammonia ice machine 13.

Claims

1. A steam efficient conditioning distribution device for a synthetic ammonia system, characterized by It includes a first boiler, a second boiler, a third boiler, a desuperheater and pressure reducer, an air separation turbine, an ammonia synthesis turbine, and a medium-pressure user steam network. A first high-pressure steam pipeline is fixedly connected between the outlet of the third boiler and the inlet of the air separation turbine. A second high-pressure steam pipeline is fixedly connected between the outlet of the second boiler and the inlet of the ammonia synthesis turbine. A first medium-pressure steam pipeline is fixedly connected between the outlet of the first boiler and the inlet of the medium-pressure user steam network. A second medium-pressure steam pipeline is fixedly connected between the second high-pressure steam pipeline and the first medium-pressure steam pipeline. A desuperheater and pressure reducer are fixedly connected to the second medium-pressure steam pipeline. A high-pressure steam interconnection pipeline is fixedly connected between the second high-pressure steam pipeline and the first high-pressure steam pipeline.

2. The high-efficiency steam regulation and distribution device for ammonia synthesis system according to claim 1, characterized in that... It also includes a changeover steam pipeline network and an ammonia refrigeration ice machine, with a first secondary medium-pressure steam pipeline fixedly connected between the outlet of the changeover steam pipeline network and the inlet of the ammonia refrigeration ice machine.

3. The high-efficiency steam regulation and distribution device for ammonia synthesis system according to claim 2, characterized in that... It also includes a waste heat boiler, and a second by-product medium-pressure steam pipeline is fixedly connected between the outlet of the waste heat boiler and the first by-product medium-pressure steam pipeline.

4. The high-efficiency steam regulation and distribution device for the ammonia synthesis system according to claim 3, characterized in that... A third medium-pressure steam pipeline is fixedly connected between the second medium-pressure steam pipeline (between the outlet of the desuperheater and the first medium-pressure steam pipeline) and the first by-product medium-pressure steam pipeline (between the outlet of the conversion steam network and the second by-product medium-pressure steam pipeline).

5. The high-efficiency steam regulation and distribution device for ammonia synthesis system according to claim 4, characterized in that... A pressure reducing valve and a first pressure gauge are fixedly installed along the medium flow direction on the third medium-pressure steam pipeline.

6. The high-efficiency steam regulation and distribution device for ammonia synthesis system according to claim 1, 2, 3, 4, or 5, characterized in that... A first shut-off valve is fixedly installed on the high-pressure steam interconnection pipeline.

7. The high-efficiency steam regulation and distribution device for ammonia synthesis system according to claim 6, characterized in that... A second shut-off valve is fixedly installed on the second medium-pressure steam pipeline between the second high-pressure steam pipeline and the inlet of the desuperheater and pressure reducer.

8. The high-efficiency steam regulation and distribution device for ammonia synthesis system according to claim 7, characterized in that... A third shut-off valve and a second pressure gauge are fixedly installed sequentially along the medium flow direction on the second medium-pressure steam pipeline between the outlet of the desuperheater and the third medium-pressure steam pipeline.

9. The high-efficiency steam regulation and distribution device for ammonia synthesis system according to claim 7 or 8, characterized in that... A third pressure gauge and a fourth shut-off valve are fixedly installed sequentially along the medium flow direction on the second high-pressure steam pipeline between the second boiler outlet and the high-pressure steam interconnection pipeline. A fourth pressure gauge and a fifth shut-off valve are fixedly installed sequentially along the medium flow direction on the first high-pressure steam pipeline between the third boiler outlet and the high-pressure steam interconnection pipeline.

10. The high-efficiency steam regulation and distribution device for ammonia synthesis system according to claim 9, characterized in that... A fifth pressure gauge is fixedly installed on the first secondary medium-pressure steam pipeline between the outlet of the change steam pipeline and the third medium-pressure steam pipeline, and a sixth pressure gauge is fixedly installed on the first medium-pressure steam pipeline between the outlet of the first boiler and the second medium-pressure steam pipeline.

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