Ammonia gas pipeline heating system

Abstract

The utility model discloses an ammonia gas pipeline heating system. In the prior art, due to pipeline blockage, insufficient ammonia gas supply can be caused, the denitration reaction cannot be fully carried out, the denitration efficiency is reduced, and NOx emission exceeds the standard. The operation cost is increased. The device comprises an ammonia gas heating device, a smoke inlet of a shell of the ammonia gas heating device is communicated with a smoke pipe of a coal economizer, an ammonia pipeline of the ammonia gas heating device is communicated with an ammonia gas incoming pipe, an outlet of the ammonia pipeline is communicated with an ammonia-air mixer, and the ammonia-air mixer is communicated with an air outlet of the ammonia gas heating device. An outlet of the ammonia-air mixer is communicated to an ammonia spraying layer of the SCR reactor through an ammonia outlet pipe; and a flue gas outlet of the shell of the ammonia gas heating device is communicated with the ammonia outlet pipe through a flue gas outlet pipe. The heating device is used for heating the ammonia gas pipeline.

Description

Technical Field

[0001] This utility model relates to an ammonia pipeline heating system. Background Technology

[0002] Currently, with increasingly stringent national requirements for NOx emissions, most coal-fired power plants employ SCR (Selective Catalytic Reduction) denitrification technology to address NOx emissions. This process, with the aid of a catalyst, efficiently converts NOx in flue gas into nitrogen and water, typically achieving a denitrification efficiency of 80%-90% or higher, meeting stringent environmental emission standards. However, this process may be affected by ammonia crystallization in the pipelines, impacting denitrification efficiency. (Crystallization can clog pipelines: Crystallized substances adhere to the inner walls of pipelines, gradually clogging ammonia pipelines over time, hindering ammonia transport and affecting the normal progress of the denitrification reaction.)

[0003] Impact on denitrification efficiency: Pipeline blockage leads to insufficient ammonia supply, preventing the denitrification reaction from proceeding fully, thus reducing denitrification efficiency and causing NOx emissions to exceed standards. Increased operating costs: Removing crystals requires additional manpower, resources, and time for cleaning and maintenance, increasing operating costs and equipment downtime. Safety hazards: Severe crystallization can lead to pipeline rupture, ammonia leaks, and other safety accidents, threatening the safety of personnel and equipment. Therefore, we can invent an ammonia pipeline heating system to prevent pipeline crystallization. Utility Model Content

[0004] The purpose of this utility model is to overcome the shortcomings of the existing technology and provide an ammonia pipeline heating system.

[0005] The above objectives are achieved through the following technical solutions:

[0006] An ammonia pipeline heating system comprises: an ammonia heating device, wherein the flue gas inlet of the outer shell of the ammonia heating device is connected to the economizer flue pipe, the ammonia supply pipe of the ammonia heating device is connected to the ammonia supply pipe, the outlet of the ammonia supply pipe is connected to the ammonia-air mixer, and the outlet of the ammonia-air mixer is connected to the ammonia injection layer of the SCR reactor through an ammonia outlet pipe.

[0007] The flue gas outlet of the outer casing of the ammonia heating device is connected to the ammonia outlet pipe via a flue gas outlet pipe.

[0008] In the aforementioned ammonia pipeline heating system, the air inlet of the ammonia-air mixer is connected to the air supply pipeline.

[0009] The ammonia pipeline heating system includes an air supply pipeline comprising a primary air duct and a dilution air duct. The primary air duct and the dilution air duct are connected to a main air outlet duct, and the main air outlet duct is connected to the air inlet of the ammonia-air mixer via a branch air outlet duct.

[0010] The ammonia pipeline heating system is described above, wherein an ammonia supply regulating valve is installed on the ammonia pipeline. Beneficial effects

[0011] 1. This utility model heats ammonia gas by setting up an ammonia gas pipeline heating system, which exchanges heat between ammonia gas and economizer flue gas, thereby preventing crystallization in the pipeline.

[0012] 2. The ammonia heating device of this utility model has an ammonia supply regulating valve, which can regulate the ammonia flow rate and thus regulate NOx. Attached Figure Description

[0013] Appendix Figure 1 This is a schematic diagram of the present invention;

[0014] In the diagram: 1. Primary air inlet; 2. Ammonia outlet pipe; 3. Dilution fan; 5. Main outlet pipe; 6. Bypass valve; 7. Economizer flue pipe; 8. Outer shell; 9. Ammonia inlet pipe; 10. Ammonia supply pipe; 11. Ammonia supply regulating valve; 12. Branch outlet pipe; 13. Ammonia-air mixer; 14. Flue gas outlet pipe; 15. Primary air duct; 16. Dilution air duct; 17. SCR reactor. Detailed Implementation

[0015] Reference Figure 1 An ammonia pipeline heating system comprises: an ammonia heating device, wherein the flue gas inlet of the outer shell 8 of the ammonia heating device is connected to the economizer flue pipe 7, the ammonia supply pipe of the ammonia heating device is connected to the ammonia supply pipe 9, the outlet of the ammonia supply pipe is connected to the ammonia-air mixer 13, and the outlet of the ammonia-air mixer is connected to the ammonia injection layer of the SCR reactor 17 through the ammonia outlet pipe 2.

[0016] Ammonia gas (110-130℃) from the ammonia buffer tank enters the ammonia heating device's ammonia supply pipe (its temperature drops to 100℃ before entering the pipe). Economizer flue gas (330-360℃) enters the outer shell of the ammonia heating device through the economizer flue pipe and exchanges heat with the ammonia gas in the ammonia supply pipe to heat the ammonia gas. After heat exchange, the ammonia gas enters the ammonia-air mixer and mixes with the air in the air supply channel. The flue gas after heat exchange and the ammonia gas from the ammonia-air mixer enter the ammonia injection layer together, and then enter the SCR reactor.

[0017] The flue gas outlet of the outer casing of the ammonia heating device is connected to the ammonia outlet pipe via the flue gas outlet pipe 14.

[0018] The air inlet of the ammonia-air mixer is connected to the air supply duct. The air supply duct includes a primary air duct 15 and a dilution air duct 16. The primary air duct and the dilution air duct are connected to the main air outlet duct 5. The main air outlet duct is connected to the air inlet of the ammonia-air mixer through a branch air outlet duct 12.

[0019] The ammonia pipeline heating system is described above, wherein an ammonia supply regulating valve 11 is installed on the ammonia pipeline.

[0020] The air supply duct has two sources: primary air 1 and dilution fan 3. The dilution fan is used during startup, while the primary air is used during normal operation.

Claims

1. An ammonia conduit heating system characterized by: The composition comprises: ammonia heating device, the ammonia heating device shell flue gas inlet communicates with the coal economizer flue, the ammonia heating device ammonia pipeline communicates with ammonia gas come, the ammonia pipeline outlet communicates with ammonia air mixer, the ammonia air mixer outlet through ammonia pipe communicates to the ammonia injection layer of SCR reactor; The ammonia heating device shell flue gas outlet communicates with the ammonia pipe through the flue gas outlet pipe.

2. An ammonia conduit heating system according to claim 1, characterized in that: The air inlet of the ammonia air mixer communicates with the air supply pipeline.

3. An ammonia conduit heating system according to claim 2, characterised in that: The air supply pipeline comprises primary air pipe and dilution air pipe, the primary air pipe communicates with the dilution air pipe to the total air outlet pipeline, the total air outlet pipeline communicates with the air inlet of the ammonia air mixer through the air outlet pipeline.

4. An ammonia conduit heating system according to claim 3, characterised in that: The ammonia pipeline is provided with ammonia supply adjusting valve.

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