CN108126464A - Boiler desulphurization denitration dedusting minimum discharge system and its desulphurization denitration dust removal method - Google Patents

Abstract

An ultra-low emission system for desulfurization, denitrification and dust removal for boilers, including a boiler, a flue, a bag filter, an induced draft fan, a combined desulfurization and denitrification water bath dedusting device, a gas-water separator, and a chimney. The boiler is connected to the bag filter in sequence through the flue , the upper part of the induced draft fan and the desulfurization and denitrification water bath dust removal combination remover, the gas-water separator is connected with the upper end of the desulfurization and denitrification water bath dust removal combination remover, and the upper end of the gas-water separator is connected to the lower part of the chimney through the second flue; the desulfurization and denitrification water bath dust removal combination There is an isolation device longitudinally in the middle of the inner chamber of the remover, which divides the inner chamber of the desulfurization and denitrification water bath dedusting combined remover into two chambers, the left and right chambers are connected at the bottom; the upper end of the left chamber is fixed with a desulfurizer and a second denitrification chamber. The air-water separator is fixed on the upper end of the right chamber, and the upper parts of the left and right chambers are cavities, the height of which is 0.3m-0.5m, and the lower part holds water. Through the technical scheme, the flue gas purification efficiency is high, which is beneficial to environmental protection, and at the same time, the investment is small and the land occupation is small.

Description

Boiler desulfurization, denitrification and dust removal ultra-low emission system and desulfurization, denitrification and dust removal method

technical field

The invention relates to a flue gas purification device and a purification method after boiler combustion, in particular to a desulfurization, denitration and dust removal ultra-low emission system for a boiler and a desulfurization, denitration and dust removal method thereof.

Background technique:

Now the flue gas produced by coal-fired biomass boilers contains different degrees of sulfur, nitrate and soot. A large amount of flue gas has caused serious pollution to the atmosphere. With the stringent control standards for nitrogen oxides and sulfur dioxide, the simultaneous realization of desulfurization, denitrification and dust removal technology has attracted increasing attention from all aspects. At present, most of the desulfurization, denitrification and dust removal technologies in flue gas are in the research and industrial demonstration stage. Since desulfurization, denitrification and dust removal are realized in one system at the same time, the investment, cost and area are large.

Invention content:

In view of the problems existing in the above-mentioned prior art, the present invention provides a desulfurization, denitrification and dust removal ultra-low emission system for boilers and a desulfurization, denitrification and dust removal method thereof, and its technical solution is:

An ultra-low emission system for desulfurization, denitrification and dust removal for boilers, including a boiler, a flue, a bag filter, an induced draft fan, a combined desulfurization and denitrification water bath dedusting device, a gas-water separator, and a chimney. The boiler is connected to the bag filter in sequence through the flue , the upper part of the induced draft fan and the desulfurization and denitrification water bath dedusting combination remover, the gas-water separator communicates with the upper end of the desulfurization and denitrification water bath dedusting combination remover, and the upper end of the gas-water separator is connected to the lower part of the chimney through the second flue;

An isolation device is installed longitudinally in the middle of the inner chamber of the combined desulfurization and denitrification water bath dust removal device, which divides the inner chamber of the desulfurization and denitrification water bath dust removal combined remover into two left and right chambers, and the bottoms of the left and right chambers are connected;

The upper end of the left chamber is fixed with a desulfurizer and a second denitrifier, and the gas-water separator is fixed at the upper end of the right chamber. The upper parts of the left and right chambers are both cavities. Hold water.

Above-mentioned technical scheme can be further improved as:

The furnace of the boiler is provided with an ammonia water denitrifier, and the distance from the ammonia water denitrifier to the bottom of the furnace is 30 cm.

An opening is provided in the middle of the bottom of the isolating device.

The bottom of the isolation device is placed above the bottom of the desulfurization and denitrification water bath dedusting combined remover, and there is a certain distance between the bottom of the former and the bottom of the latter.

The isolation device is an isolation wall or an isolation plate.

The combined desulfurization and denitrification water bath dedusting device is also provided with a dust treatment pool connected to the bottom of the right chamber. The height of the dust treatment pool is higher than or equal to the water surface of the left and right chambers, but lower than the height of the left and right chambers.

The dust treatment pool is also connected to a circulating water pump, the water inlet end of the water pump extends into the dust treatment pool, and the water outlet end of the water pump is connected to several nozzles, the nozzles are placed on the upper part of the left chamber and placed on the desulfurizer and the second Below the denitrifier and above the flue gas inlet, it is used to atomize the flue gas and accelerate the water circulation speed.

The upper part of the chimney is provided with a flue gas on-line detector, the height of the flue gas on-line detector is 39 meters from the lower end of the chimney, the top of the chimney is provided with a lightning rod, and the bottom of the chimney is provided with a lightning protection grounding device.

The method of desulfurization, denitrification and dust removal for boilers with desulfurization, denitrification and dust removal ultra-low emission system. When coal-fired biomass is burned in the furnace of the boiler, the ammonia water denitrifier is used for preliminary denitrification treatment, and the generated flue gas enters the bag filter for the first time. Dust removal, then the flue gas enters the upper cavity of the left chamber of the desulfurization and denitrification water bath dust removal combined remover through the induced draft fan, and at the same time, the desulfurizer and the second denitrifier in the upper part of the left chamber spray desulfurizer and denitrification agent, and the nozzle of the water pump Atomize and spray water to atomize the flue gas for further desulfurization, denitrification and dust removal. As the pressure in the upper part of the left chamber gradually increases, the flue gas enters the water in the left chamber and enters the right chamber along the lower part of the left and right chambers. , and continue to enter the upper cavity of the right chamber upwards to achieve further dust removal in the water; then the flue gas enters the gas-water separator for separation, and then the flue gas after gas-water separation enters the chimney through the second flue, and the separated water Fall back into the right chamber.

The desulfurization and denitrification water bath dedusting combination remover purifies a large amount of flue gas sludge and then cleans it out after settling in the dust treatment pool on the side of the right chamber to ensure the quality of the flue gas purifying water;

The desulfurization agent is alkaline sodium hydroxide solution with a concentration of 5-10‰, and the denitrification agent is ammonia water with a concentration of 26% or urea solution with a concentration of 30%.

Through this technical solution, the flue gas purification efficiency is high, it is energy-saving and environmentally friendly, and at the same time, it has small investment, small footprint, flexible installation, safe and stable operation, and convenient and quick operation and maintenance.

Description of drawings:

Figure 1 is a structural schematic diagram of a desulfurization, denitrification and dust removal ultra-low emission system for boilers;

Fig. 2 is the structural representation of embodiment 1 of the connection relationship between the separation wall and the desulfurization and denitrification water bath dedusting combined remover;

Fig. 3 is the structural representation of embodiment 2 of the connection relationship between the separation wall and the desulfurization and denitrification water bath dedusting combined remover;

Among them: 1. Boiler, 2. Flue, 3. Bag filter, 4. Induced fan, 5. Water pump, 6. Desulfurization and denitrification water bath dedusting combination remover, 7. Partition wall, 8. Dust treatment pool, 9. Chimney, 10. Gas-water separator, 11. Second flue, 12. Flue gas online detector, 13. Lightning protection grounding device, 14. Ammonia denitrifier, 15. Desulfurizer, 16. Second denitrifier.

Detailed ways:

Example 1:

As shown in Figures 1 and 2: a desulfurization, denitration and dust removal ultra-low emission system for boilers, including boiler 1, flue 2, bag filter 3, induced draft fan 4, desulfurization and denitrification water bath dust removal combination remover 6, gas-water separation Device 10, chimney 9, and boiler 1 are sequentially connected to bag filter 3, induced draft fan 4 and the upper part of desulfurization and denitrification water bath dust removal combined remover 6 through flue 2, and gas-water separator 10 is connected to desulfurization and denitrification water bath dust removal combined remover 6 The upper end is connected, and the upper end of the gas-water separator 10 is connected to the lower part of the chimney 9 through the second flue;

A partition wall 7 is longitudinally arranged in the middle of the inner cavity of the combined desulfurization and denitrification water bath dust removal device 6, and the inner cavity of the desulfurization and denitrification water bath dust removal combined remover 6 is divided into left and right chambers. The chambers are communicated through openings at the bottom of the partition wall 7;

The upper end of the left chamber is fixed with a desulfurizer 15 and a second denitrifier 16, and the gas-water separator 10 is fixed at the upper end of the right chamber. m, the lower part holds water. The furnace of the boiler is provided with an ammonia water denitrifier 14, and the distance from the ammonia water denitrifier to the bottom of the furnace is 30 cm, and the denitrification effect is the best.

The desulfurization and denitrification water bath dedusting combination remover 6 is also provided with a dust treatment pool 8 communicating with the bottom of the right chamber. The height of the dust treatment pool is equal to the water surface of the left and right chambers, but lower than the height of the left and right chambers.

The dust treatment pool 8 is also connected to the circulating water pump 5, the water inlet end of the water pump 5 stretches into the dust treatment pool 8, and the water outlet end of the water pump 5 is connected to several nozzles, and the nozzles are placed on the top of the left chamber and placed Below the desulfurizer 15 and the second denitrifier 16 and above the flue gas inlet end, it is used to atomize the flue gas and accelerate the circulation speed of water.

The upper part of the chimney is provided with a flue gas on-line detector 12, the height of the flue gas on-line detector is 39 meters from the lower end of the chimney, the top of the chimney is provided with a lightning rod, and the bottom of the chimney is provided with a lightning protection grounding device 13.

Example 2:

As shown in Figure 3, a desulfurization, denitrification and dust removal ultra-low emission system for boilers includes a boiler 1, a flue 2, a bag filter 3, an induced draft fan 4, a combined desulfurization and denitrification water bath dedusting device 6, and a gas-water separator 10 , the chimney 9, and the boiler 1 are sequentially connected to the upper part of the bag filter 3, the induced draft fan 4 and the desulfurization and denitrification water bath dedusting combination remover 6 through the flue 2, and the gas-water separator 10 communicates with the upper end of the desulfurization and denitrification water bath dedusting combination remover 6 , the upper end of the gas-water separator 10 is connected to the lower part of the chimney 9 through the second flue;

A partition wall 7 is longitudinally arranged in the middle of the desulfurization and denitrification water bath dust removal combined remover 6, and the desulfurization and denitrification water bath dust removal combined remover 6 is divided into left and right chambers, and the bottom of the partition wall 7 is placed in the desulfurization and denitrification water bath dust removal Combining the upper part of the bottom of the stripper, and the bottom of the former has a certain distance from the bottom of the latter,

The left and right chambers communicate with each other through the gap between the bottom of the partition wall 7 and the bottom of the desulfurization and denitrification water bath dedusting combination remover 6;

The upper end of the left chamber is fixed with a desulfurizer 15 and a second denitrifier 16, and the gas-water separator 10 is fixed at the upper end of the right chamber. m, the lower part holds water. The furnace of the boiler is provided with an ammonia water denitrifier 14, and the distance from the ammonia water denitrifier to the bottom of the furnace is 30 cm, and the denitrification effect is the best.

The desulfurization and denitrification water bath dedusting combination remover 6 is also provided with a dust treatment pool 8 communicating with the bottom of the right chamber. The height of the dust treatment pool is equal to the water surface of the left and right chambers, but lower than the height of the left and right chambers.

The dust treatment pool 8 is also connected to the circulating water pump 5, the water inlet end of the water pump 5 stretches into the dust treatment pool 8, and the water outlet end of the water pump 5 is connected to several nozzles, and the nozzles are placed on the top of the left chamber and placed Below the desulfurizer 15 and the second denitrifier 16, it is used to atomize the flue gas and accelerate the circulation speed of water.

The upper part of the chimney is provided with a flue gas on-line detector, and the flue gas on-line detector 12 is at a height of 39 meters from the lower end of the chimney. The top of the chimney is provided with a lightning rod, and the bottom of the chimney is provided with a lightning protection grounding device.

According to customer needs or space constraints, desulfurization, desulfurization and denitrification water bath dedusting combination remover 6 can be placed underground, and bag filter 3 is placed above desulfurization and denitrification water bath dedusting combination remover 6, which can prevent freezing in winter and reduce land use. usage area.

Its desulfurization, denitrification and dust removal process is as follows: when coal-fired biomass is burned in the furnace of the boiler, the ammonia water denitrifier is used for preliminary denitrification treatment, and the generated flue gas enters the bag filter for the first dust removal, and then the flue gas passes through the induced draft fan. Enter the cavity in the upper part of the left chamber of the desulfurization and denitrification water bath dedusting combined remover, and at the same time, the desulfurizer and the second denitrifier in the upper part of the left chamber spray desulfurization agent and denitrification agent, and the nozzle of the water pump sprays water to spray the flue gas Atomization, further desulfurization, denitrification and dust removal, as the pressure in the upper part of the left chamber gradually increases, the flue gas enters the water in the left chamber and enters the right chamber along the lower part of the left and right chambers, and continues upward into the upper part of the right chamber The hollow cavity realizes further desulfurization, denitrification and dust removal in the water; then the flue gas enters the gas-water separator for separation, and then the flue gas after gas-water separation enters the chimney through the second flue, and the separated water falls back to the right chamber.

The desulfurization and denitrification water bath dedusting combination remover purifies a large amount of flue gas through the dust treatment pool on the right side of the chamber, and then it is cleaned out after sedimentation, which is convenient for cleaning.

Through this system, after removal, they are: dust 0-8 mg/m³, sulfur dioxide 10-30 mg/m³, nitrogen oxides 100-180 mg/m³. The removal rate fully meets our current ultra-low emission standards: dust 10mg/m³, sulfur dioxide 50 mg/m³, nitrogen oxides 200 mg/m³.

Example 3:

As shown in Figure 1, the desulfurization, denitrification and dust removal method of the ultra-low emission system for boilers uses desulfurization, denitrification and dust removal. When burning coal and biomass in the furnace of the boiler 1, the initial denitrification treatment is carried out by the ammonia water denitrifier 14, and the smoke produced The gas enters the bag filter 3 for the first dust removal, and then the flue gas enters the upper cavity of the left chamber of the desulfurization and denitrification water bath dust removal combined remover 6 through the induced draft fan 4, and the desulfurizer 15 and the second denitrifier at the upper part of the left chamber 16 Spray desulfurization agent and denitrification agent, the spray head of the water pump sprays water to atomize the flue gas, further desulfurization, denitrification and dust removal, as the pressure on the upper part of the left chamber gradually increases, the flue gas enters the water in the left chamber along the Enter the right chamber through the connection between the lower parts of the left and right chambers, and continue upwards into the upper cavity of the right chamber to achieve further desulfurization, denitrification and dust removal in the water; then the flue gas enters the gas-water separator for separation 11, and then the gas-water separation The flue gas enters the chimney 9 through the second flue 11, and the separated water falls back to the right chamber.

The desulfurization and denitrification water bath dedusting combination remover 6 purifies a large amount of flue gas through the dust treatment pool 8 on the right side of the chamber. The sludge is settled and then cleaned out to ensure the quality of the water for purifying the flue gas.

According to the content of sulfur dioxide and nitrogen oxides in the flue gas, the desulfurization agent is selected as alkaline sodium hydroxide solution with a concentration of 5-10‰, and the denitrification agent is ammonia water with a concentration of 26% or urea solution with a concentration of 30%.

Through the invention, the flue gas purification efficiency is high, and the removal effect is good. After removal, it is: dust 0-8 mg/m³, sulfur dioxide 10-30mg/m³, nitrogen oxides 100-180mg/m³, fully reaching my country's current ultra-low Emission standards: dust 10mg/m³, sulfur dioxide 50 mg/m³, nitrogen oxides 200 mg/m³.

The above is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Anyone skilled in the art can easily think of changes or substitutions within the technical scope disclosed in the present invention. Should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be determined by the protection scope of the claims.

Claims (10)

1. a kind of boiler desulphurization denitration dedusting minimum discharge system, it is characterised in that：Including boiler, flue, bag filter, Air-introduced machine, desulphurization denitration water bath dust-removing combination remover, moisture trap, chimney, boiler connect cloth bag by flue order and remove The top of dirt device, air-introduced machine and desulphurization denitration water bath dust-removing combination remover, moisture trap and desulphurization denitration water bath dust-removing group The connection of remover upper end is closed, moisture trap upper end connects chimney lower part by the second flue；

Longitudinal direction is equipped with isolating device among desulphurization denitration water bath dust-removing combination remover inner cavity, and desulphurization denitration water bath dust-removing is combined Remover inner cavity is divided into left and right two chambers, and left and right cavity bottom communicates；

Left chamber's inner upper end is fixed with devulcanizer and the second denitrator, and moisture trap is fixed at right chamber upper end, left Right chamber top is cavity, and the cavity height is 0.3m-0.5m, and lower part is filled with water.

2. boiler as described in claim 1 desulphurization denitration dedusting minimum discharge system, it is characterised in that：The stove of the boiler Ammonium hydroxide denitrator is equipped in thorax, and ammonium hydroxide denitrator is 30 centimetres apart from burner hearth bottom.

3. boiler as described in claim 1 desulphurization denitration dedusting minimum discharge system, it is characterised in that：The isolating device Opening is equipped among bottom.

4. boiler as described in claim 1 desulphurization denitration dedusting minimum discharge system, it is characterised in that：The isolating device Bottom is placed in the top of desulphurization denitration water bath dust-removing combination remover bottom, and the former bottom and the bottom of the latter have a spacing From.

5. the boiler desulphurization denitration dedusting minimum discharge system as described in 1-4 any claims, it is characterised in that：Described Isolating device is divider wall or isolation board.

6. boiler as claimed in claim 5 desulphurization denitration dedusting minimum discharge system, it is characterised in that：The desulphurization denitration Water bath dust-removing combination remover is additionally provided with the dust processing pond communicated with right chamber bottom, and the height of dust processing pond is higher than or waits In the water surface of left and right chamber, less than the height of left and right chamber.

7. boiler as claimed in claim 6 desulphurization denitration dedusting minimum discharge system, it is characterised in that：The dust processing Pond is also connected with water circulating pump, and the water inlet end of the water pump is stretched into dust processing pond, and the water outlet of water pump connects several nozzles, institute Nozzle is stated to be placed in the top of left chamber and be placed in below devulcanizer and the second denitrator, above gas inlet.

8. boiler as described in claim 1 desulphurization denitration dedusting minimum discharge system, it is characterised in that：The chimney top Equipped with flue gas on-line checking device, the chimney top is equipped with lightning rod, and bottom end is equipped with lightning protection earthing device.

9. the boiler described in claim 1-8 any claims is removed with the desulphurization denitration of desulphurization denitration dedusting minimum discharge system The method of dirt, it is characterised in that：It is carried out just through ammonium hydroxide denitrator first during stove chamber inner combustion of the coal-fired biomass-burning in boiler After walking denitration process, the flue gas of generation enters bag filter and carries out dedusting for the first time, and then flue gas enters desulfurization by air-introduced machine The cavity on the left chamber top of denitration water bath dust-removing combination remover, while the devulcanizer on left chamber top, the second denitrator spray Desulfurizing agent and denitrfying agent are spilt, the nozzle of water pump carries out atomizing spray, flue gas is atomized, further desulphurization denitration dedusting, with a left side The pressure on chamber top gradually increases, and flue gas enters in the water of left chamber and enters right chamber along the place of communicating of left and right chamber lower portion Room continues upwardly into the cavity on right chamber top, realizes the further dedusting in water；Then flue gas enters moisture trap Separation, then the flue gas after gas-water separation enters chimney by the second flue, and the water isolated is fallen after rise into right chamber；

The dust processing pond that the mud of a large amount of flue gases of purification passes through right chamber side in desulphurization denitration water bath dust-removing combination remover It is cleared again after precipitation, ensures the quality of the water of purifying smoke.

10. the boiler as claimed in claim 9 method of the desulphurization denitration dedusting of desulphurization denitration dedusting minimum discharge system, It is characterized in that：The desulfurizing agent be concentration 5-10 ‰ alkali sodium hydroxide solution, denitrfying agent be a concentration of 26 ﹪ ammonium hydroxide or The urea liquid of 30 ﹪.