Shift gas waste heat recycling system

Abstract

The utility model discloses a shift gas waste heat recycling system which comprises a shift converter, a waste heat boiler, a heat exchanger, a cooler and a separator, a shift gas outlet of the shift converter is communicated with a gas inlet of the waste heat boiler through a pipeline, a gas outlet of the waste heat boiler is communicated with a thermal medium inlet of the heat exchanger through a pipeline, a thermal medium outlet of the heat exchanger is communicated with an inlet of the cooler through a pipeline, and an outlet of the cooler is communicated with an inlet of the separator through a pipeline; an outlet of the desalted water incoming pipeline is communicated with a cold medium inlet of the heat exchanger through a pipeline, a cold medium outlet of the heat exchanger is communicated with a water inlet of the deaerator through a pipeline, a water outlet of the deaerator is communicated with a water inlet of the waste heat boiler through a pipeline, and a steam outlet of the waste heat boiler is communicated with a steam inlet of the deaerator through a pipeline. The system has the advantages that the waste heat of the shift gas can be fully recycled, the operation load of the cooler is reduced, the energy consumption of the system can be reduced, and the economic benefit of an enterprise is favorably improved.

Description

Technical Field:

[0001] The utility model relates to a waste heat recovery and utilization system, in particular to a shift gas waste heat recovery and utilization system. Background Art:

[0002] In the process of synthesizing ammonia, it is necessary to convert CO in the synthesis gas into hydrogen through shift hydrogen production. Specifically, CO and water vapor react under the action of a catalyst to produce CO2 and hydrogen. This reaction is an exothermic reaction, and the temperature of the obtained shift gas is relatively high and carries a large amount of heat. If only circulating water is used to cool it, the amount of circulating water used is large, and the circulating water after heat exchange needs to increase the operating power of the circulating water cooling fan, resulting in increased energy consumption; moreover, the heat carried by the shift gas is not utilized, seriously affecting the economic benefits of the enterprise. Content of the Utility Model:

[0003] In order to solve the above problems, the purpose of the utility model is to provide a shift gas waste heat recovery and utilization system.

[0004] The utility model is implemented by the following technical solutions:

[0005] A shift gas waste heat recovery and utilization system, which includes a shift furnace, a waste heat boiler, a heat exchanger, a cooler, and a separator;

[0006] The shift gas outlet of the shift furnace is connected to the air inlet of the waste heat boiler through a pipeline, the air outlet of the waste heat boiler is connected to the heat medium inlet of the heat exchanger through a pipeline, the heat medium outlet of the heat exchanger is connected to the inlet of the cooler through a pipeline, and the outlet of the cooler is connected to the inlet of the separator through a pipeline;

[0007] The outlet of the demineralized water inlet pipeline is connected to the cold medium inlet of the heat exchanger through a pipeline, the cold medium outlet of the heat exchanger is connected to the water inlet of the deaerator through a pipeline, the water outlet of the deaerator is connected to the water inlet of the waste heat boiler through a pipeline, and the steam outlet of the waste heat boiler is connected to the steam inlet of the deaerator through a pipeline.

[0008] Further, the steam outlet of the waste heat boiler is also connected to the steam inlet of the superheater through a pipeline, and the steam outlet of the superheater is connected to the steam inlet of the steam turbine through a pipeline.

[0009] Further, a temperature sensor is provided at the water outlet of the deaerator, and a flow regulating valve is provided on the pipeline connecting the steam outlet of the waste heat boiler and the steam inlet of the deaerator. The signal output end of the temperature sensor is signal-connected to the signal input end of the controller, and the signal output end of the controller is signal-connected to the signal input end of the flow regulating valve.

[0010] Advantages of the present utility model:

[0011] The conversion gas carrying a large amount of heat first enters the waste heat boiler to by-produce low-pressure steam, and then enters the heat exchanger as a heat medium to preheat the demineralized water. At the same time, by introducing the low-pressure steam by-produced by the waste heat boiler into the deaerator, the temperature of the demineralized water is further increased to reach the inlet water temperature requirement of the waste heat boiler; the outlet water temperature of the deaerator can also be monitored by a temperature sensor provided at the outlet of the deaerator, and then the steam amount entering the deaerator can be adjusted to ensure the temperature requirement of the boiler feed water.

[0012] The present utility model can realize the full recovery and reuse of the waste heat of the conversion gas, reduce the operation load of the cooler at the same time, reduce the system energy consumption, and is beneficial to improving the economic benefits of the enterprise. Description of the drawings:

[0013] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model or the prior art, the following will briefly introduce the drawings required to be used in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0014] Figure 1 It is a schematic diagram of the system connection of this embodiment;

[0015] Figure 2 It is a schematic control diagram of this embodiment.

[0016] In the figure: conversion furnace 1, waste heat boiler 2, heat exchanger 3, cooler 4, separator 5, demineralized water supply pipeline 6, deaerator 7, superheater 8, steam turbine 9, temperature sensor 10, flow regulating valve 11, controller 12. Specific implementation manners:

[0017] The following will clearly and completely describe the technical solutions in the embodiments of the present utility model with reference to the drawings in the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, rather than 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 efforts belong to the protection scope of the present utility model.

[0018] Embodiment 1:

[0019] As Figure 1-2 shown, a conversion gas waste heat recovery and utilization system includes a conversion furnace 1, a waste heat boiler 2, a heat exchanger 3, a cooler 4, and a separator 5;

[0020] The outlet of the shift converter 1 is connected to the inlet of the waste heat boiler 2 through a pipeline. The outlet of the waste heat boiler 2 is connected to the inlet of the heat medium of the heat exchanger 3 through a pipeline. The outlet of the heat medium of the heat exchanger 3 is connected to the inlet of the cooler 4 through a pipeline. The outlet of the cooler 4 is connected to the inlet of the separator 5 through a pipeline;

[0021] The outlet of the demineralized water supply pipeline 6 is connected to the inlet of the cold medium of the heat exchanger 3 through a pipeline. The outlet of the cold medium of the heat exchanger 3 is connected to the water inlet of the deaerator 7 through a pipeline. The water outlet of the deaerator 7 is connected to the water inlet of the waste heat boiler 2 through a pipeline. The steam outlet of the waste heat boiler 2 is connected to the steam inlet of the deaerator 7 through a pipeline. The steam outlet of the waste heat boiler 2 is also connected to the steam inlet of the superheater 8 through a pipeline. The steam outlet of the superheater 8 is connected to the steam inlet of the steam turbine 9 through a pipeline.

[0022] A temperature sensor 10 is provided at the water outlet of the deaerator 7. A flow regulating valve 11 is provided on the pipeline connecting the steam outlet of the waste heat boiler 2 and the steam inlet of the deaerator 7. The signal output end of the temperature sensor 10 is signal-connected to the signal input end of the controller 12. The signal output end of the controller 12 is signal-connected to the signal input end of the flow regulating valve 11.

[0023] Working principle:

[0024] When using this embodiment, the shift gas generated by the shift converter 1 with a temperature of about 390 °C first enters the waste heat boiler 2 to by-produce low-pressure steam at 0.53 MPa and 160 °C. After passing through the waste heat boiler 2, the temperature of the shift gas itself drops to 165 °C, and then it enters the heat exchanger 3 as a heat medium to preheat the demineralized water from the demineralized water supply pipeline 6 to a temperature of about 80 °C. At the same time, the temperature of the shift gas drops to 120 °C. After that, the shift gas continues to enter the cooler 4 to continue cooling, so that the oil and water carried in it are condensed. After gas-liquid separation through the separator 5, the separated hydrogen is used for the ammonia synthesis process.

[0025] The demineralized water preheated by the heat exchanger 3 enters the deaerator 7. At the same time, by introducing the low-pressure steam by-produced by the waste heat boiler 2 into the deaerator 7, the temperature of the demineralized water is further increased through the low-pressure steam to reach 130 °C, meeting the water inlet temperature requirement of the waste heat boiler 2. The water outlet temperature of the deaerator 7 can be monitored by the temperature sensor 10 provided at the water outlet of the deaerator 7. When the water outlet temperature is too low, the opening of the flow regulating valve 11 can be increased to increase the amount of steam entering the deaerator 7. When the water outlet temperature is too high, the opening of the flow regulating valve 11 can be reduced to reduce the amount of steam entering the deaerator 7.

[0026] Since the amount of steam by-produced by the waste heat boiler 2 is much greater than the amount of steam required by the deaerator 7, the excess steam can also be heated into superheated steam by the superheater 8 for the steam turbine 9 to do work and generate electricity.

[0027] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A conversion gas waste heat recovery and utilization system, characterized in that: It includes a shift furnace, a waste heat boiler, a heat exchanger, a cooler and a separator; The conversion gas outlet of the conversion furnace is connected to the air inlet of the waste heat boiler through a pipeline, the air outlet of the waste heat boiler is connected to the heat medium inlet of the heat exchanger through a pipeline, the heat medium outlet of the heat exchanger is connected to the inlet of the cooler through a pipeline, and the outlet of the cooler is connected to the inlet of the separator through a pipeline; The outlet of the desalted water pipeline is connected to the cold medium inlet of the heat exchanger through a pipeline, the cold medium outlet of the heat exchanger is connected to the water inlet of the deaerator through a pipeline, the water outlet of the deaerator is connected to the water inlet of the waste heat boiler through a pipeline, and the steam outlet of the waste heat boiler is connected to the steam inlet of the deaerator through a pipeline.

2. The conversion gas waste heat recovery system according to claim 1, characterized in that: The steam outlet of the waste heat boiler is also connected to the steam inlet of the superheater through a pipeline, and the steam outlet of the superheater is connected to the steam inlet of the steam turbine through a pipeline.

3. The system for recovering waste heat from conversion gas according to claim 1, characterized in that: A temperature sensor is provided at the water outlet of the deaerator, and a flow regulating valve is provided on the pipeline connecting the steam outlet of the waste heat boiler and the steam inlet of the deaerator. The signal output end of the temperature sensor is signal-connected to the signal input end of the controller, and the signal output end of the controller is signal-connected to the signal input end of the flow regulating valve.

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