CN220091004U

CN220091004U - Ammonia molecule purification recovery unit in denitration flue gas

Info

Publication number: CN220091004U
Application number: CN202320649789.8U
Authority: CN
Inventors: 徐宾胜; 张远领; 马永军; 马国军; 张磊; 姜辉; 蔡利新
Original assignee: Lianyungang Petrochemical Co Ltd
Current assignee: Lianyungang Petrochemical Co Ltd
Priority date: 2023-03-29
Filing date: 2023-03-29
Publication date: 2023-11-28
Anticipated expiration: 2033-03-29

Abstract

The utility model discloses a device for purifying and recycling ammonia molecules in denitration flue gas, which belongs to the technical field of tail gas purification and is characterized in that: the exhaust purification device is arranged on the other side of the furnace body, the air suction port of the induced draft fan is communicated with the furnace body through a bent pipe I, the air outlet of the induced draft fan is communicated with the exhaust purification device through a bent pipe II, the exhaust purification device is communicated with the heat exchanger through a water inlet pipe, and the other end of the heat exchanger is communicated with an external water outlet pipe to form circulation. The technical problem of the existence of ammonia condition emergence in the work of current flue gas denitration equipment, ammonia along with the flue gas evacuation, cause the raw materials extravagant is solved, mainly is applied to the boiler denitration tail gas and contains ammonia gas purification aspect.

Description

Ammonia molecule purification recovery unit in denitration flue gas

Technical Field

The utility model belongs to the technical field of tail gas purification, and particularly relates to a device for purifying and recycling ammonia molecules in denitration flue gas.

Background

The furnace body denitration process is that a reducing agent NH3 is sprayed into the flue gas through a nozzle in an ammonia spraying grid and is fully mixed with the flue gas, the reducing agent NH3 selectively reacts with NOx in the flue gas to generate N2 and H2O under the action of a catalyst, and the chemical and physical processes of a Selective Catalytic Reduction (SCR) flue gas denitration process are as follows:

a chemical Process

The reducing agent NH3 is sprayed into the flue gas through the spraying device and is fully mixed with the flue gas, and the reducing agent NH3 selectively reacts with NOx in the flue gas under the action of a catalyst to generate N2 and H2O instead of being oxidized by O2, so the method is called as 'selectivity'. The main reactions are as follows:

NO+NO2+2NH3→2N2+3H2O

4NO+4NH3+O2→4N2+6H2O

b physical procedure

The physical process refers to the process of converting liquid ammonia into gaseous ammonia by passing the liquid ammonia through a liquid ammonia evaporator. The pressure of the liquid ammonia is sent to a liquid ammonia evaporator, the shell side of the liquid ammonia evaporator is filled with steam, the heat medium-water in the shell side is heated, the liquid ammonia is filled in the tube side, and the liquid ammonia is evaporated into gas ammonia through the heating tube side and then enters the ammonia buffer tank. The ammonia amount entering the liquid ammonia evaporator is automatically controlled by a pneumatic regulating valve in front of the liquid ammonia evaporator, so that the buffer tank is maintained to operate within a certain pressure range.

The liquid ammonia SCR denitration process can capture most NOX in the flue gas, and has higher denitration efficiency.

Prior art application number: CN202021270017.6 discloses a cement SCR denitration and flue gas waste heat recovery integrated device, including exhaust-heat boiler, denitration system, soot blowing system, cleaning system and detecting system, exhaust-heat boiler includes flue gas entry, evaporimeter, economizer, exhaust port, the exhaust-heat boiler top is the flue gas entry, be fixed with the evaporimeter under the flue gas entry, the evaporimeter below is denitration system, denitration system includes atomizing spray gun, ammonia spraying tuber pipe, denitration bed layer, first heat transfer tuber pipe, install the atomizing spray gun on the ammonia spraying tuber pipe, the inlet end of atomizing spray gun is connected with compressed air system, and the inlet end of atomizing spray gun is connected with reaction medicament system. The device is convenient to use by combining various structures, the waste heat boiler is improved less, the investment and occupied space of deamination equipment are reduced, the activity of the catalyst is ensured, the loss of ammonia is reduced, the cost is saved, and the device is uniform in sampling.

The ammonia gas is exhausted along with the flue gas, so that raw materials are wasted, and aiming at the problems, the ammonia molecule purifying and recycling device in the denitration flue gas is provided for the purposes of the inventor.

Disclosure of Invention

The utility model aims to: the utility model aims to provide an ammonia molecule purifying and recycling device in denitration flue gas, which aims to solve the technical problem that ammonia is exhausted along with flue gas and raw materials are wasted when ammonia is excessively generated in the working process of the existing flue gas denitration equipment.

In order to achieve the above purpose, the present utility model provides the following technical solutions: the utility model provides an ammonia molecule purification recovery unit in denitration flue gas, includes furnace body, heat exchanger, spouts ammonia grid, catalysis layer, the empty blender of ammonia, draught fan and tail gas cleanup unit the inside supreme heat exchanger, spouting ammonia grid and the catalysis layer of installing in proper order down of furnace body, spout the empty blender of ammonia grid one side installation, the empty blender of ammonia passes through straight tube I and spouts ammonia grid intercommunication, furnace body top installation draught fan, its characterized in that: the exhaust gas purification device is arranged on the other side of the furnace body, the device can filter ammonia in smoke to be purified and then is emptied, an induced draft fan air inlet is communicated with the furnace body through a bent pipe I, an induced draft fan air outlet is communicated with the exhaust gas purification device through a bent pipe II, the exhaust gas purification device is communicated with the heat exchanger through a water inlet pipe, cold water firstly passes through the exhaust gas purification device and then passes through the heat exchanger for heat exchange, and the other end of the heat exchanger is communicated with an external water outlet pipe to form circulation.

Preferably, the tail gas purifying device comprises a tank body, a vertical pipe, a smoke outlet pipe, an electronic liquid level meter, a spiral pipe, a straight pipe II and a liquid outlet pipe, wherein the vertical pipe is arranged in the tank body and used for feeding smoke, the top of the vertical pipe is connected with an air outlet of the induced draft fan through the bent pipe II, a spray head is arranged at the bottom of the vertical pipe and then sprayed out by the spray head, the smoke outlet pipe is also arranged at the top of the tank body, the smoke after purifying the ammonia is emptied from the smoke outlet pipe, a group of support plates and the electronic liquid level meter are respectively arranged at the side edges of the tank body and used for determining the liquid level of water in the tank body, the utility model discloses a jar body side winding spiral pipe and hugs closely jar external wall, the spiral pipe passes through the backup pad and supports, the spiral pipe includes inlet end and play water end, spiral pipe play water end passes through inlet tube and heat exchanger intercommunication, spiral pipe inlet end and outside inlet tube intercommunication form the circulation spiral pipe inlet end one side installation motorised valve I, install straight tube II and jar body intercommunication between motorised valve I and the spiral pipe inlet end, install motorised valve II on the straight tube II, jar body bottom installation drain pipe, install motorised valve III on the drain pipe.

Preferably, the smoke outlet pipe is bent, so that dust is prevented from falling into the tank body to pollute liquid in the tank.

Compared with the prior art, the utility model has the beneficial effects that:

through the principle that design exhaust purification device utilized ammonia extremely to dissolve in water purifies unnecessary ammonia in the flue gas, the ammonia that generates belongs to reversible reaction, this reaction can lead to the temperature to continuously rise when ammonia constantly reacts with water with exothermic reaction and reduce ammonia solubility, carry out heat transfer through the spiral pipe and guarantee that jar internal water is in low temperature state always, prevent the ammonia that dissolves in water because of the temperature is too high volatilizees again, guaranteed the biggest solubility of jar internal water-soluble ammonia simultaneously, simultaneously also can change new water with saturated aqueous ammonia solution, compared with prior art, this device can retrieve ammonia molecule and effectively prevent that there is the ammonia condition to take place simultaneously the convenience with ammonia water mixture recovery precipitation crystal in flue gas denitration equipment work, the manufacturing cost of enterprise has also been practiced thrift when purifying the flue gas.

Drawings

FIG. 1 is a flow chart of flue gas denitration process and ammonia-containing gas purification according to the present utility model;

fig. 2 is a structural view of the exhaust gas purifying apparatus of the present utility model;

fig. 3 is a front view of the exhaust gas purifying apparatus of the present utility model;

fig. 4 is a plan view of the exhaust gas purifying apparatus of the present utility model.

In the figure: 1. a furnace body; 2. a heat exchanger; 3. an ammonia spraying grid; 4. a catalytic layer; 5. an ammonia-air mixer; 6. a straight pipe I; 7. an induced draft fan; 8. an exhaust gas purifying device; 9. a bent pipe I; 10. a bent pipe II; 11. a water inlet pipe; 12. an external water outlet pipe; 13. a tank body; 14. a standpipe; 15. a spray head; 16. a smoke outlet pipe; 17. a support plate; 18. an electronic level gauge; 19. a spiral tube; 20. an external water inlet pipe; 21. an electric valve I; 22. a straight pipe II; 23. an electric valve II; 24. a liquid outlet pipe; 25. and an electric valve III.

Detailed Description

The following description of the embodiments of the present utility model will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present utility model, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

Example 1

Referring to fig. 1-4, the present utility model provides a technical solution: the utility model provides an ammonia molecule purification recovery unit in denitration flue gas, includes furnace body 1, heat exchanger 2, spouts ammonia grid 3, catalytic layer 4, ammonia empty mixer 5, draught fan 7 and tail gas cleanup unit 8 the inside heat exchanger 2, spouting ammonia grid 3 and the catalytic layer 4 of installing in proper order from down of furnace body 1, spout ammonia grid 3 one side and install ammonia empty mixer 5, ammonia empty mixer 5 communicates with spouting ammonia grid 3 through straight tube I6, furnace body 1 top installation draught fan 7, its characterized in that: the exhaust gas purifying device 8 is arranged on the other side of the furnace body 1, an air suction inlet of the induced draft fan 7 is communicated with the furnace body 1 through an elbow I9, an air outlet of the induced draft fan 7 is communicated with the exhaust gas purifying device 8 through an elbow II 10, the exhaust gas purifying device 8 is communicated with the heat exchanger 2 through a water inlet pipe 11, and the other end of the heat exchanger 2 is communicated with an external water outlet pipe 12 to form circulation.

The tail gas purification device 8 comprises a tank 13, a vertical pipe 14, a smoke outlet pipe 16, an electronic liquid level meter 18, a spiral pipe 19, a straight pipe II 22 and a liquid outlet pipe 24, wherein the vertical pipe 14 is installed in the tank 13, the top of the vertical pipe 14 is connected with an air outlet of a draught fan 7 through a bent pipe II 10, a spray head 15 is installed at the bottom of the vertical pipe 14, the smoke outlet pipe 16 is also installed at the top of the tank 13, the smoke outlet pipe 16 is in a bent shape, a group of supporting plates 17 and the electronic liquid level meter 18 are respectively installed on the side edge of the tank 13, the spiral pipe 19 is wound on the side edge of the tank 13 and is tightly attached to the outer wall of the tank 13, the spiral pipe 19 is supported by the supporting plates 17, the spiral pipe 19 comprises a water inlet end and a water outlet end, the water outlet end of the spiral pipe 19 is communicated with a heat exchanger 2 through the water inlet pipe 11, the water inlet end of the spiral pipe 19 is communicated with an external water inlet pipe 20 to form circulation, an electric valve I21 is installed on one side of the water inlet end of the spiral pipe 19, an electric valve I22 and a water inlet end of the spiral pipe 19 are installed between the electric valve I21 and the water inlet end of the spiral pipe II 22 and the straight pipe II 22 are communicated with the tank 13, an electric valve II 22 is installed on the side of the tank 13, the straight pipe II is 23 is respectively, the electric valve is installed on the side of the straight pipe 24, and the bottom is installed on the electric pipe 25 is installed on the bottom of the straight pipe 25.

The working principle and the using flow of the utility model are as follows: the flue gas purification work, the flue gas moves from bottom to top from furnace body 1, firstly, heat exchange is carried out through heat exchanger 2, the heat of the flue gas is recovered, ammonia air mixer 5 mixes ammonia with air and sprays out by ammonia spraying grid 3 and carries out primary denitration to the flue gas, then the flue gas enters catalytic layer 4 and reacts with internal catalyst and carries out secondary denitration, ammonia molecule and flue gas are sucked out from furnace body 1 by draught fan 7 and discharged into tail gas purification device 8 and are purified, water is injected into tank 13 of purification device 8, excessive ammonia molecule is dissolved in water, then purification and evacuation are carried out through exhaust pipe 16 on tail tank 13, cold water enters spiral pipe 19 and carries out heat exchange to water in tank 13, at this moment, electric valve I21 is normally open, electric valve II 23 on straight pipe II 22 is closed, cold water directly passes through spiral pipe 19 and enters into heat exchanger 2 through inlet tube 11 and carries out heat exchange to the flue gas and forms the circulation, guarantee that water in tank 13 is in normal temperature state and can also realize the heat recovery to furnace body 1 flue gas.

Example 2

The working principle and the using flow of the utility model are as follows: after a certain time, water in the tank 13 can become saturated solution, the tank 13 needs to be replaced in advance for water purification and recovery operation, the boiler is temporarily stopped, an electric valve III 25 of a liquid outlet pipe 24 at the bottom of the tank 13 is opened by a worker operating a control system, the ammonia water mixture to be saturated in the tank 13 is emptied and recovered, when no liquid fluid is observed by the worker, the electric valve III 25 of the liquid outlet pipe 24 at the bottom of the tank 13 is closed by the worker operating the control system, an electric valve I21 is closed, an electric valve II 23 on a straight pipe II 22 is opened, water supplementing operation is carried out in the tank 13, when the water level reaches the position of an electronic liquid level meter 18, water supplementing is stopped, the electric valve I21 is opened by the response of the electronic liquid level meter 18, the electric valve II 23 is closed for entering heat exchange operation, and then the worker starts the whole equipment for production.

Although embodiments of the present utility model have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made therein without departing from the principles and spirit of the utility model, the scope of which is defined in the appended claims and their equivalents.

Claims

1. The utility model provides an ammonia molecule purifies recovery unit in denitration flue gas, includes furnace body (1), heat exchanger (2), spouts ammonia grid (3), catalysis layer (4), empty blender of ammonia (5), draught fan (7) and tail gas cleanup unit (8) inside follow supreme heat exchanger (2), the ammonia grid of spouting (3) and the catalysis layer (4) of installing in proper order down of furnace body (1), empty blender of ammonia (5) are installed to ammonia grid (3) one side, and empty blender of ammonia (5) are through straight tube I (6) and ammonia grid of spouting (3) intercommunication, draught fan (7) are installed at furnace body (1) top, its characterized in that: tail gas purification device (8) are installed to furnace body (1) opposite side, draught fan (7) inlet scoop pass through return bend I (9) and furnace body (1) intercommunication, draught fan (7) air outlet pass through return bend II (10) and tail gas purification device (8) intercommunication, tail gas purification device (8) are through inlet tube (11) and heat exchanger (2) intercommunication, heat exchanger (2) other end and outside outlet pipe (12) intercommunication form the circulation.

2. The ammonia molecule purification and recovery device in denitration flue gas according to claim 1, wherein: the tail gas purification device (8) comprises a tank body (13), a vertical pipe (14), a smoke outlet pipe (16), an electronic liquid level meter (18), a spiral pipe (19), a straight pipe II (22) and a liquid outlet pipe (24), wherein the vertical pipe (14) is arranged in the tank body (13), the top of the vertical pipe (14) is connected with an air outlet of a draught fan (7) through a bent pipe II (10), a spray head (15) is arranged at the bottom of the vertical pipe (14), the smoke outlet pipe (16) is further arranged at the top of the tank body (13), a group of support plates (17) and electronic liquid level meters (18) are respectively arranged at the side edges of the tank body (13), the spiral pipe (19) is wound on the side edges of the tank body (13) and is tightly attached to the outer wall of the tank body (13), the spiral pipe (19) is supported by the support plates (17), the spiral pipe (19) comprises a water inlet end and a water outlet end, the water outlet end of the spiral pipe (19) is communicated with a heat exchanger (2) through a water inlet pipe (11), the water inlet end of the spiral pipe (19) is communicated with an external water inlet pipe (20) to form a circulation, one side of the spiral pipe (19) is electrically driven by one side of the water inlet end (21), an electrically driven valve I (21) and the water inlet end (22) is connected with the straight pipe II (22) through the water inlet end (22), an electric valve II (23) is arranged on the straight pipe II (22), a liquid outlet pipe (24) is arranged at the bottom of the tank body (13), and an electric valve III (25) is arranged on the liquid outlet pipe (24).

3. The ammonia molecule purifying and recycling device in denitration flue gas according to claim 2, wherein: the smoke outlet pipe (16) is bent.