Improved production device of waste heat boiler without gas collecting bag

Abstract

The utility model relates to the field of production of synthetic ammonia from coal, in particular to an improved production device of a waste heat boiler without a gas collecting bag, which comprises a low-pressure waste heat boiler, and the inlet end of the low-pressure waste heat boiler is respectively connected with a process gas inlet pipe and a desalted water inlet pipe. Process gas which is subjected to heat exchange by the medium-pressure waste heat boiler and the low-pressure waste heat boiler enters the process gas inlet pipe; the outlet end of the low-pressure waste heat boiler is connected with a process gas outlet pipe and a steam-water separator, one path of the outlet end of the steam-water separator is connected with a steam delivery pipe, and the steam delivery pipe is used for delivering steam without water or generating electricity and recycling the steam with water to a condensate tank; the process gas outlet pipe is used for delivering the process gas subjected to heat exchange; and the other path of the outlet end of the steam-water separator is connected with a deaerator, and steam condensate is used as water replenishment of the deaerator. Compared with the prior art, the device has the advantages that the phenomenon that 0.5 MPa steam as a byproduct of the low-pressure waste heat boiler carries water is effectively solved, and the safe and stable operation of the device is ensured.

Description

Technical Field

[0001] The utility model relates to the field of coal-based synthetic ammonia production, and specifically provides an improved production device without a gas-collecting bag waste heat boiler. Background Art

[0002] In the coal-to-ammonia production process, waste heat boilers are typically installed to recover heat from the process gas. These heat exchangers use the high-temperature process gas with low-temperature desalted water to produce steam as a byproduct, thereby increasing the company's profitability. Currently, two types of waste heat boilers are commonly used in industry: those with integrated gas collectors and those without. Waste heat boilers with integrated gas collectors offer better steam-water separation and higher-quality byproduct steam. However, due to their relatively complex structure, they are more expensive than waste heat boilers without gas collectors.

[0003] In the coal-to-ammonia process conversion section, the main reactions are This reaction is exothermic, decreasing with increasing temperature. Low temperatures favor the shift reaction. To remove heat from the process gas, improve the conversion rate of the shift reaction, and ensure that the heat in the process gas is not wasted, the shift section is generally equipped with a medium-pressure waste heat boiler, a low-pressure waste heat boiler, and a low-low-pressure waste heat boiler. The process gas enters the medium-pressure waste heat boiler, the low-pressure waste heat boiler, and the low-low-pressure waste heat boiler in sequence, exchanging heat with low-temperature desalted water. These byproducts are 3.8MPa, 2.5MPa, and 0.5MPa of steam, respectively, which can be exported or used for power generation, thereby improving the company's economic benefits.

[0004] In traditional processes, in order to reduce equipment investment, medium-pressure waste heat boilers and low-pressure waste heat boilers that produce steam with higher pressure levels of 3.8MPa and 2.5MPa generally use waste heat boilers with built-in gas collection bag structures, while low-pressure waste heat boilers that produce low-pressure steam with a by-product of 0.5MPa use a structure without gas collection bag.

[0005] However, during actual operation, the lack of a gas-collecting bag in the waste heat boiler resulted in insufficient boiling depth, leading to significant water contamination in the 0.5MPa byproduct steam, impacting the safe and stable operation of the unit. Directly replacing the waste heat boiler with a built-in gas-collecting bag would have required significant investment, and the old, unused waste heat boiler would have remained idle, wasting equipment resources. Summary of the Invention

[0006] The utility model aims to solve the above-mentioned deficiencies in the prior art and provides an improved production device for a waste heat boiler without an air collecting bag, which has a reasonable design, a simple structure, energy saving and consumption reduction, and can be remotely controlled.

[0007] The technical solution adopted by the utility model to solve its technical problems is:

[0008] An improved production device for a waste heat boiler without an air collection bag includes a low-pressure waste heat boiler, wherein the inlet ends of the low-pressure waste heat boiler are respectively connected to a process gas inlet pipe and a desalted water inlet pipe, and the process gas entering the process gas inlet pipe is the process gas after heat exchange with the medium-pressure waste heat boiler and the low-pressure waste heat boiler;

[0009] The outlet end of the low-pressure waste heat boiler is connected to a process gas outlet pipe and a steam-water separator. The outlet end of the steam-water separator is connected to a steam delivery pipe. The steam delivery pipe sells the steam without water or uses it for power generation, and recovers the steam with water to the condensate tank; the process gas outlet pipe delivers the process gas after heat exchange.

[0010] The other outlet of the steam-water separator is connected to a deaerator, and the steam condensate is used as water to make up the deaerator.

[0011] Furthermore, the low-pressure waste heat boiler is connected to the steam-water separator in a direct pipeline manner, and the directly connected pipeline is the steam-water separator air inlet pipe.

[0012] Furthermore, a wire mesh demister II is provided in the low-pressure waste heat boiler, and a wire mesh demister I is provided in the steam-water separator.

[0013] Furthermore, the steam-water separator is connected to the deaerator through a steam condensate delivery pipe, the steam condensate delivery pipe is provided with a self-regulating valve, and the steam-water separator is installed with a liquid level gauge.

[0014] Furthermore, the liquid level meter is provided with remote transmission and liquid level high and low limit functions, and the liquid level of the steam-water separator is monitored on the DCS. At the same time, an automatic adjustment loop is set up between the liquid level meter and the self-regulating valve, and the self-regulating valve realizes automatic adjustment of the DCS according to the set value of the liquid level meter.

[0015] Furthermore, the steam delivery pipe is connected to a drain pipe, and is connected to the condensate tank through the drain pipe, and a drain valve is provided on the drain pipe.

[0016] Preferably, the steam-water separator is provided with a manhole.

[0017] Compared with the prior art, the improved production device of the waste heat boiler without gas collection bag of the utility model has the following outstanding beneficial effects:

[0018] This new system effectively addresses the problem of water inclusion in the 0.5MPa steam produced by the low-pressure waste heat boiler byproduct by adding a steam-water separator, which is then equipped with a wire mesh demister I, a deaerator, and a condensate tank. This ensures safe and stable operation of the device. The newly added steam-water separator is simple, requires little investment, and is economical.

[0019] The separated steam condensate is used as the make-up water for the deaerator, which can effectively reduce the amount of desalted water added to the deaerator, thus saving energy and reducing consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0021] Attachment Figure 1 The present invention is a structural diagram of an improved production device without a gas collection bag waste heat boiler.

[0022] The symbols in the accompanying drawings represent:

[0023] 1. Low-pressure waste heat boiler, 2. Steam-water separator, 3. Deaerator, 4. Process gas inlet pipe, 5. Process device outlet pipe, 6. Desalted water inlet pipe, 7. Steam-water separator inlet pipe, 8. Steam outlet pipe, 9. Steam condensate outlet pipe, 10. Liquid level gauge, 11. Self-regulating valve, 12. Wire mesh demister I, 13. Wire mesh demister II, 14. Manhole, 15. Condensate tank, 16. Drain pipe, 17. Drain valve. DETAILED DESCRIPTION

[0024] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but they are not intended to limit the present invention.

[0025] In the present invention, unless otherwise specified, directional words such as "up, down, left, right" generally refer to the up, down, left, and right shown in the reference drawings; "inside and outside" refer to the inside and outside relative to the outline of each component itself.

[0026] A best embodiment is given below:

[0027] like Figure 1 As shown, in this embodiment, an improved production device for a waste heat boiler without an air collection bag includes a low-pressure waste heat boiler 1. The inlet ends of the low-pressure waste heat boiler 1 are respectively connected to a process gas inlet pipe 4 and a desalted water inlet pipe 6. The process gas entering the process gas inlet pipe 4 is the process gas after heat exchange with the medium-pressure waste heat boiler and the low-pressure waste heat boiler.

[0028] The outlet of the low-pressure waste heat boiler 1 is connected to a steam-water separator 2, and the outlet of the steam-water separator 2 is connected to a steam delivery pipe 8, which delivers the steam without water to the outside or uses it for power generation;

[0029] The steam delivery pipe 8 is connected to a drain pipe 16, and is connected to a condensate tank 15 through the drain pipe 16. A drain valve 17 is provided on the drain pipe 16 to recover the steam with water to the condensate tank 15.

[0030] The other outlet of the steam-water separator 2 is connected to the deaerator 3, and the steam condensate is used as water replenishment for the deaerator 3.

[0031] The low-pressure waste heat boiler 1 is connected to the steam-water separator 2 by a direct pipeline connection, and the directly connected pipeline is the steam-water separator air inlet pipe 7 .

[0032] In this embodiment, the low-pressure waste heat boiler 1 is equipped with a wire mesh demister II 13. When the by-produced 0.5 MPa steam passes through the wire mesh demister II 13, it can partially remove the water entrained in the steam. The steam-water separator 2 is equipped with a wire mesh demister I 12. Through the wire mesh demister II 12, the remaining water vapor in the by-produced 0.5 MPa steam is effectively separated and removed.

[0033] The steam-water separator 2 is connected to the deaerator 3 through a steam condensate delivery pipe 9 , on which a self-regulating valve 11 is provided, and a liquid level gauge 10 is installed on the steam-water separator 2 .

[0034] The liquid level meter 10 is equipped with remote transmission and liquid level high and low limit functions, and monitors the liquid level of the steam-water separator 2 on the DCS. At the same time, an automatic adjustment loop is set up between the liquid level meter 10 and the self-regulating valve 11, and the self-regulating valve 11 realizes automatic adjustment of the DCS according to the set value of the liquid level meter 10.

[0035] The steam-water separator 2 is also provided with a manhole 14. If the separation effect of the steam-water separator 2 is not good, or the equipment is operating abnormally, maintenance personnel can enter the equipment through the manhole 14 to troubleshoot and repair the problem.

[0036] When the improved production device of the waste heat boiler without a gas collection bag in this embodiment is in use, the process gas after heat exchange between the medium-pressure waste heat boiler and the low-pressure waste heat boiler has a temperature of approximately 200°C and a pressure of approximately 6.2 MPa, and enters the tube of the low-pressure waste heat boiler 1 through the process gas inlet pipe 4; the desalted water has a pressure of approximately 1.8 MPa and a temperature of approximately 120°C, and enters the tube space of the low-pressure waste heat boiler through the desalted water inlet pipe 6.

[0037] In the low-pressure waste heat boiler 1, the high-temperature process gas and the low-temperature desalted water are heat exchanged, and the by-product 0.5MPa steam is sent to the steam-water separator 2 through the steam-water separator inlet pipe 7. The process gas temperature after heat exchange is about 160℃ and is sent to the downstream process section through the process gas outlet pipe 5.

[0038] The 0.5MPa steam produced as a by-product of the low-pressure waste heat boiler 1 enters the steam-water separator 2 through the steam-water separator air inlet pipe 7. In the steam-water separator 2, the water vapor entrained in the 0.5MPa steam is effectively separated, and the 0.5MPa steam without water is sent out through the steam delivery pipe 8 to be sold outside or used for power generation; the separated steam condensate is sent to the deaerator 3 through the steam condensate delivery pipe 9.

[0039] The inlet end of the deaerator 3 is connected to the steam condensate delivery pipe 9, and the steam condensate is used as water to replenish the deaerator 3, which can effectively reduce the amount of desalted water added to the deaerator 3 and save energy and reduce consumption.

[0040] The inlet end of the condensate tank 15 is connected to the drain pipe 16. The condensate generated by the by-product 0.5 MPa steam due to heat loss during pipeline transportation is discharged into the condensate tank through the drain pipe 16 for storage and recycling.

[0041] A liquid level gauge 10 is installed on the steam-water separator 2, and an automatic valve 11 is installed on the steam condensate outlet pipe 9. The liquid level gauge 10 features remote transmission and high and low level limits, enabling the DCS to monitor the liquid level of the steam-water separator 2. An automatic adjustment loop is also established between the liquid level gauge 10 and the automatic valve 11, allowing the DCS to automatically adjust the valve 11 based on the set value of the liquid level gauge 10. This makes operation more convenient and accurate, ensuring safe and stable operation of the device.

[0042] The steam-water separator 2 is directly connected to the low-pressure waste heat boiler 1 by a pipeline, without any other equipment or valves in between, so the steam-water separator 2 does not need to be equipped with a separate safety valve accessory, which simplifies the equipment structure and reduces equipment investment.

[0043] A steam trap 17 is installed on the steam trap pipe 16. The steam trap 17 can automatically identify steam and water. When the by-product 0.5MPa steam produces condensate due to heat loss during pipeline transportation, the steam trap 17 automatically opens to discharge the condensate into the condensate tank, thereby achieving steam blocking and water drainage, energy saving and emission reduction.

[0044] The embodiment described above is only one of the preferred specific implementation methods of the present invention. Common changes and substitutions made by those skilled in the art within the scope of the technical solution of the present invention should be included in the protection scope of the present invention.

Claims

1. An improved production device for a waste heat boiler without an air collection bag, comprising a low-pressure waste heat boiler, characterized in that: The inlet ends of the low-pressure waste heat boilers are respectively connected to a process gas inlet pipe and a desalted water inlet pipe, and the process gas entering the process gas inlet pipe is the process gas after heat exchange with the medium-pressure waste heat boiler and the low-pressure waste heat boiler; The outlet end of the low-pressure waste heat boiler is connected to a process gas outlet pipe and a steam-water separator. The outlet end of the steam-water separator is connected to a steam delivery pipe. The steam delivery pipe sells the steam without water or uses it for power generation, and recovers the steam with water to the condensate tank; the process gas outlet pipe delivers the process gas after heat exchange. The other outlet of the steam-water separator is connected to a deaerator, and the steam condensate is used as water to make up the deaerator.

2. The improved production device of a waste heat boiler without an air collection bag according to claim 1, characterized in that: The low-pressure waste heat boiler is connected to the steam-water separator in a direct pipeline manner, and the directly connected pipeline is the steam-water separator air inlet pipe.

3. The improved production device of a waste heat boiler without an air collection bag according to claim 2, characterized in that: The low-pressure waste heat boiler is provided with a wire mesh demister II, and the steam-water separator is provided with a wire mesh demister I.

4. The improved production device of a waste heat boiler without an air collection bag according to claim 3, characterized in that: The steam-water separator is connected to the deaerator through a steam condensate delivery pipe, a self-regulating valve is provided on the steam condensate delivery pipe, and a liquid level gauge is installed on the steam-water separator.

5. The improved production device of a waste heat boiler without an air collection bag according to claim 4, characterized in that: The liquid level meter is equipped with remote transmission and liquid level high and low limit functions, and monitors the liquid level of the steam-water separator on the DCS. At the same time, an automatic adjustment loop is set up between the liquid level meter and the self-regulating valve, and the self-regulating valve realizes automatic adjustment of the DCS according to the set value of the liquid level meter.

6. The improved production device of a waste heat boiler without an air collection bag according to claim 5, characterized in that: The steam delivery pipe is connected to a drain pipe, and is connected to a condensate tank through the drain pipe, and a drain valve is provided on the drain pipe.

7. The improved production device of a waste heat boiler without an air collection bag according to claim 6, characterized in that: A manhole is provided on the steam-water separator.

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