Desulfurization, denitration, dust removal and defluorination integrated system for kiln tail gas treatment

Abstract

The utility model relates to the technical field of kiln tail gas treatment, and discloses a desulfurization, denitrification, dust removal and defluorination integrated system for kiln tail gas treatment, which comprises a kiln flue gas collecting header pipe, and a flue gas bag-type dust collector is fixedly mounted on the right side of the kiln flue gas collecting header pipe. The outer side of the flue gas bag-type dust collector is fixedly connected with a steel ladder stand, the right side of the flue gas bag-type dust collector is communicated with a connecting pipeline, the right side of the connecting pipeline is communicated with an induced draft fan, and the right side of the induced draft fan is communicated with a defluorination washing tower through the connecting pipeline; a defluorination sedimentation tank is arranged below the defluorination washing tower, and the right side of the defluorination washing tower is communicated with a desulfurization, denitrification, dust removal and defluorination integrated tower through a connecting pipeline. According to the desulfurization, denitrification, dust removal and defluorination integrated system for kiln tail gas treatment, the ultra-low emission standard value of kiln flue gas is met, the desulfurization, denitrification, dust removal and defluorination processes are completed in the integrated tower at the same time, and the purposes of achieving multiple purposes at one stroke, saving energy and reducing consumption are achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of kiln tail gas treatment, in particular to an integrated desulfurization, denitrification, dust removal and defluorination system for kiln tail gas treatment. Background Art

[0002] Industrial furnaces refer to thermal equipment that uses the heat generated by fuel combustion or electric energy conversion in industrial production to melt, fuse, roast (calcine), heat, dry distill, gasify, etc. materials or workpieces, including eight categories: melting furnaces, melting furnaces, roast (calcine) furnaces (kilns), heating furnaces, heat treatment furnaces, drying furnaces (kilns), coke ovens, gas generators, etc. Industrial furnaces are widely used in steel, coking, nonferrous metals, building materials, petrochemicals, chemicals, machinery manufacturing and other industries, and play an important supporting role in industrial development. At the same time, they are also the main source of air pollution in the industrial field. For this reason, a furnace tail gas treatment system is needed.

[0003] According to the Chinese patent publication number CN 108499343 A, an integrated desulfurization, denitrification and dust removal system for tail gas of coal-fired boiler is disclosed; the technical problem solved is that the tail gas treatment of traditional coal-fired boilers is basically an independent unit. This tail gas treatment system has large investment, many equipments, large floor space, complex operation and high operating cost, which is difficult for heating enterprises to bear. The adopted technical scheme and system include an ozone oxidation system, an absorbent preparation system, an absorption and washing integrated system and a dehydration system. The ozone oxidation system and the absorbent preparation system are both connected to the absorption and washing integrated system, and the absorption and washing integrated system is connected to the dehydration system. Advantages: This system adopts the "dynamic wave scrubber simultaneous desulfurization, dust removal and denitrification process" to replace the bag dust removal, spray urea solution or denitrification in the furnace, and empty tower spray desulfurization, realizing integrated desulfurization, denitrification and dust removal, with small floor space, simple operation, low operating cost, and extremely high desulfurization, denitrification and dust removal efficiency. Utility Model Content

[0004] 1. Technical issues to be solved

[0005] In view of the deficiencies in the prior art, the utility model provides an integrated desulfurization, denitrification, dust removal and defluorination system for kiln tail gas treatment.

[0006] (II) Technical solution

[0007] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: an integrated desulfurization, denitrification, dust removal and defluorination system for kiln tail gas treatment, comprising a smoke collecting main pipe from the kiln, a smoke bag dust collector is fixedly installed on the right side of the smoke collecting main pipe from the kiln, a steel ladder is fixedly connected to the outside of the smoke bag dust collector, a connecting pipe is connected to the right side of the smoke bag dust collector, an induced draft fan is connected to the right side of the connecting pipe, a defluorination washing tower is connected to the right side of the induced draft fan through a connecting pipe, and the A defluorination sedimentation tank is arranged below the defluorination washing tower, and a desulfurization, denitrification, dust removal and defluorination integrated tower is arranged on the right side of the defluorination washing tower through a connecting pipe, a dust removal and demisting section is fixedly installed above the desulfurization, denitrification, dust removal and defluorination integrated tower, and a chimney direct discharge section is fixedly installed above the dust removal and demisting section, a desulfurization, denitrification, dust removal and defluorination integrated sedimentation tank is arranged below the desulfurization, denitrification, dust removal and defluorination integrated tower, and a de-pressure filtration system and a sewage thallium and fluorine removal system are arranged on the right side of the desulfurization, denitrification, dust removal and defluorination integrated sedimentation tank.

[0008] Preferably, the method comprises the following steps:

[0009] S1. Air intake: The exhaust gas from the kiln is collected through the main smoke collecting pipe of the kiln and sent to the next device for treatment;

[0010] S2. Dust removal: The collected kiln exhaust gas is dedusted through a flue gas bag filter to remove dust particles in the flue gas;

[0011] S3, defluorination:

[0012] S31, defluorination washing: the flue gas after being pressurized by the induced draft fan passes through the defluorination washing tower for preliminary defluorination treatment;

[0013] S32, defluorination precipitation: the wastewater generated after defluorination washing in the defluorination washing tower is discharged into the defluorination precipitation tank for precipitation treatment;

[0014] S33, sewage discharge: the sewage after sedimentation is treated to remove thallium and fluorine, and then discharged through the sewage pump;

[0015] S4, desulfurization, denitrification, dust removal and defluorination:

[0016] S41, desulfurization, denitrification and defluorination: The flue gas after the preliminary defluorination treatment in the defluorination washing tower is subjected to deep desulfurization, denitrification and defluorination treatment through the desulfurization, denitrification, dust removal and defluorination integrated tower;

[0017] S42, wastewater sedimentation: the wastewater generated in the desulfurization, denitration, dust removal and defluorination integrated tower is discharged into the desulfurization, denitration, dust removal and defluorination integrated sedimentation tank for sedimentation;

[0018] S43. Wastewater discharge: The wastewater after sedimentation is treated to remove thallium and fluorine, and finally the wastewater is discharged centrally through a sewage pump.

[0019] S5. Flue gas emission:

[0020] S51, dust removal and demisting: dust removal and demisting treatment is performed on the flue gas after being treated by the desulfurization, denitration, dust removal and defluorination integrated tower so as to facilitate discharge;

[0021] S52. Emission: Flue gas that has passed the test and meets the standards is discharged directly into the atmosphere through the chimney direct discharge section.

[0022] Preferably, the flue gas bag dust collector is made of woven filter cloth or non-woven felt, and uses the filtering effect of the fiber fabric to filter the dust-containing gas. When the dust-containing gas enters the bag dust collector, the dust with large particles and high specific gravity settles down due to gravity and falls into the ash hopper. When the gas containing finer dust passes through the filter material, the dust is retained, so that the gas is purified. At the same time, the flue gas bag dust collector is easy to replace.

[0023] Preferably, the steel ladder is arranged on the outside of the flue gas bag filter, which makes it convenient for the staff to regularly clean the bags in the flue gas bag filter and also facilitates the replacement of the bags, thereby making the dust removal efficiency of the flue gas bag filter higher.

[0024] Preferably, the induced draft fan increases the working pressure of the gas with the help of external input kinetic energy, creates an air pressure environment, and then discharges the gas, thereby pressurizing the gas and sending the pressurized gas into the defluorination washing tower. The model of the induced draft fan is Y--boiler induced draft fan.

[0025] Preferably, the defluorination washing tower and the integrated desulfurization, denitrification, dust removal and defluorination tower adopt a gas-liquid reverse absorption treatment method, that is, the liquid is sprayed downward from the top of the tower in the form of mist (or small droplets), and the exhaust gas is conveyed by the tower body (reverse flow) to achieve the purpose of gas-liquid contact, thereby transferring the pollutants in the gas to the liquid, and then separating the clean gas from the contaminated liquid to achieve the purpose of purifying the air.

[0026] Desulfurization process:

[0027] SO2+NaClO2 (live)+2H2O=2H2SO4+NaCl

[0028] H2SO4+2CaOH=Ca2SO4+2H2O

[0029] Denitrification process:

[0030] 4NO+3NaClO2(live)+2H2O=4HNO3+3NaCl

[0031] CaOH+HNO3=CaNO3+H2O

[0032] Defluorination process:

[0033] CaOH+HF=CaF+H2O

[0034] Preferably, the wastewater generated in the defluorination washing tower and the desulfurization, denitrification, dust removal and defluorination integrated tower is discharged into the defluorination sedimentation tank and the desulfurization, denitrification, dust removal and defluorination integrated sedimentation tank for sedimentation respectively, and the treated wastewater is recycled through a circulation pump, thereby improving resource utilization.

[0035] Preferably, the dust removal and demisting section removes dust and mist from the treated flue gas, and at the same time detects the flue gas after dust removal and demisting. The flue gas that meets the detection standards is discharged into the atmosphere through the chimney direct discharge section, thereby meeting the ultra-low emission requirements of the kiln exhaust gas.

[0036] (III) Beneficial effects

[0037] Compared with the prior art, the utility model provides an integrated desulfurization, denitrification, dust removal and defluorination system for kiln tail gas treatment, which has the following beneficial effects:

[0038] 1. This integrated desulfurization, denitrification, dust removal and defluorination system for kiln exhaust treatment can make the chimney emission of NOX ≤ 100mg / Nm3, SO2 ≤ 50mg / Nm3, particulate matter ≤ 10mg / Nm3, fluoride ≤ 4mg / Nm3, meeting the ultra-low emission standard value of kiln flue gas.

[0039] 2. This kind of kiln exhaust gas treatment uses an integrated system for desulfurization, denitrification, dust removal and defluorination. The desulfurization, denitrification, dust removal and defluorination processes are completed simultaneously in the integrated tower, achieving the goal of energy saving and consumption reduction at one stroke. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0041] Figure 1 This is a flow chart of the utility model.

[0042] In the figure: 1. Main smoke collection pipe for flue gas from the kiln; 2. Flue gas bag dust collector; 3. Steel ladder; 4. Connecting pipes; 5. induced draft fan; 6. Defluorination washing tower; 7. Defluorination sedimentation tank; 8. Integrated desulfurization, denitrification, dust removal and defluorination tower; 9. Dust removal and demisting section; 10. Chimney direct discharge section; 11. Integrated desulfurization, denitrification, dust removal and defluorination sedimentation tank; 12. De-filter system and sewage thallium and defluorination system. DETAILED DESCRIPTION

[0043] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments.

[0044] Example 1

[0045] like Figure 1 As shown, the utility model provides an integrated desulfurization, denitrification, dust removal and defluorination system for kiln tail gas treatment, including a kiln smoke collection main pipe 1, a flue gas bag dust collector 2 is fixedly installed on the right side of the kiln smoke collection main pipe 1, a steel ladder 3 is fixedly connected to the outside of the flue gas bag dust collector 2, a connecting pipe 4 is connected to the right side of the flue gas bag dust collector 2, an induced draft fan 5 is connected to the right side of the connecting pipe 4, a defluorination washing tower 6 is connected to the right side of the induced draft fan 5 through the connecting pipe 4, and a defluorination washing tower 6 is provided below the defluorination washing tower 6. A defluorination sedimentation tank 7 is provided, and a desulfurization, denitrification, dust removal and defluorination integrated tower 8 is provided on the right side of the defluorination washing tower 6 through a connecting pipe 4, a dust removal and demisting section 9 is fixedly installed above the desulfurization, denitrification, dust removal and defluorination integrated tower 8, and a chimney direct discharge section 10 is fixedly installed above the dust removal and demisting section 9, a desulfurization, denitrification, dust removal and defluorination integrated sedimentation tank 11 is provided below the desulfurization, denitrification, dust removal and defluorination integrated tower 8, and a de-pressure filtration system and a sewage thallium and fluorine removal system 12 are provided on the right side of the desulfurization, denitrification, dust removal and defluorination integrated sedimentation tank 11.

[0046] The flue gas bag filter 2 is made of textile filter cloth or non-textile felt, and uses the filtering effect of fiber fabric to filter the dust-containing gas. When the dust-containing gas enters the bag filter, the dust with large particles and high specific gravity settles down due to gravity and falls into the ash hopper. When the gas containing finer dust passes through the filter material, the dust is retained, so that the gas is purified. At the same time, the flue gas bag filter 2 is easy to replace.

[0047] The steel ladder 3 is arranged on the outside of the flue gas bag filter 2. The steel ladder 3 facilitates the staff to regularly clean the bags in the flue gas bag filter 2 and also facilitates the replacement of the bags, thereby making the dust removal efficiency of the flue gas bag filter 2 higher.

[0048] The induced draft fan 5 uses the external input kinetic energy to increase the working pressure of the gas, create an air pressure environment, and then discharge the gas, thereby pressurizing the gas and sending the pressurized gas into the defluorination washing tower 6. The model of the induced draft fan 5 is Y6-30-12 boiler induced draft fan.

[0049] Example 2

[0050] like Figure 1 As shown, based on Example 1, the utility model provides a technical solution:

[0051] The following steps are involved:

[0052] S1, air intake: the exhaust gas from the kiln is collected through the kiln smoke collection main pipe 1 and sent to the next device for treatment;

[0053] S2, dust removal: The collected kiln exhaust gas is dedusted by the flue gas bag filter 2 to remove dust particles in the flue gas;

[0054] S3, defluorination:

[0055] S31, defluorination washing: the flue gas pressurized by the induced draft fan 5 passes through the defluorination washing tower 6 for preliminary defluorination treatment;

[0056] S32, defluorination precipitation: the wastewater generated after defluorination washing in the defluorination washing tower 6 is discharged into the defluorination precipitation tank 7 for precipitation treatment;

[0057] S33, sewage discharge: the sewage after sedimentation is treated to remove thallium and fluorine, and then discharged through the sewage pump;

[0058] S4, desulfurization, denitrification, dust removal and defluorination:

[0059] S41, desulfurization, denitrification and defluorination: the flue gas after the preliminary defluorination treatment by the defluorination washing tower 6 is subjected to deep desulfurization, denitrification and defluorination treatment by the desulfurization, denitrification, dust removal and defluorination integrated tower 8;

[0060] S42, wastewater sedimentation: the wastewater generated in the desulfurization, denitration, dust removal and defluorination integrated tower 8 is discharged into the desulfurization, denitration, dust removal and defluorination integrated sedimentation tank 11 for sedimentation;

[0061] S43. Wastewater discharge: The wastewater after sedimentation is treated to remove thallium and fluorine, and finally the wastewater is discharged centrally through a sewage pump.

[0062] S5. Flue gas emission:

[0063] S51, dust removal and demisting: dust removal and demisting are performed on the flue gas treated by the desulfurization, denitration, dust removal and defluorination integrated tower 8 so as to facilitate discharge;

[0064] S52, emission: the flue gas that meets the standards after testing is directly discharged into the atmosphere through the chimney direct discharge section 10.

[0065] The defluorination washing tower 6 and the desulfurization, denitrification, dust removal and defluorination integrated tower 8 adopt a gas-liquid reverse absorption treatment method, that is, the liquid is sprayed downward from the top of the tower in the form of mist (or small droplets), and the exhaust gas is conveyed by the tower body (reverse flow) to achieve the purpose of gas-liquid contact, thereby transferring the pollutants in the gas to the liquid, and then separating the clean gas from the contaminated liquid to achieve the purpose of purifying the air.

[0066] Desulfurization process:

[0067] SO2+NaClO2 (live)+2H2O=2H2SO4+NaCl

[0068] H2SO4+2CaOH=Ca2SO4+2H2O

[0069] Denitrification process:

[0070] 4NO+3NaClO2(live)+2H2O=4HNO3+3NaCl

[0071] CaOH+HNO3=CaNO3+H2O

[0072] Defluorination process:

[0073] CaOH+HF=CaF+H2O

[0074] The wastewater generated in the defluorination washing tower 6 and the desulfurization, denitration, dust removal and defluorination integrated tower 8 is discharged into the defluorination sedimentation tank 7 and the desulfurization, denitration, dust removal and defluorination integrated sedimentation tank 11 for sedimentation respectively. At the same time, the treated wastewater is recycled through a circulation pump, thereby improving resource utilization.

[0075] The dust removal and demisting section 9 removes dust and mist from the treated flue gas, and at the same time tests the flue gas after dust removal and demisting. The flue gas that meets the test standards is discharged into the atmosphere through the chimney direct discharge section 10, thereby meeting the ultra-low emission requirements of the kiln exhaust gas.

Claims

1. An integrated system for desulfurization, denitrification, dust removal and defluorination for treating kiln tail gas, comprising a main fume collecting pipe (1) for fume from the kiln, characterized in that: A fume bag filter (2) is fixedly installed on the right side of the fume collecting main pipe (1) from the kiln, a steel ladder (3) is fixedly connected to the outside of the fume bag filter (2), a connecting pipe (4) is connected to the right side of the fume bag filter (2), an induced draft fan (5) is connected to the right side of the connecting pipe (4), a defluorination washing tower (6) is connected to the right side of the induced draft fan (5) through the connecting pipe (4), a defluorination sedimentation tank (7) is arranged below the defluorination washing tower (6), and the defluorination washing tower (6) is connected to the right side of the induced draft fan (5) through the connecting pipe (4). A desulfurization, denitrification, dust removal and defluorination integrated tower (8) is connected to the right side of the desulfurization, denitrification, dust removal and defluorination integrated tower (8) through a connecting pipe (4); a dust removal and demisting section (9) is fixedly installed above the desulfurization, denitrification, dust removal and defluorination integrated tower (8); a chimney direct discharge section (10) is fixedly installed above the dust removal and demisting section (9); a desulfurization, denitrification, dust removal and defluorination integrated sedimentation tank (11) is arranged below the desulfurization, denitrification, dust removal and defluorination integrated tower (8); and a de-pressurization filter system and a sewage thallium and fluorination removal system (12) are arranged on the right side of the desulfurization, denitrification, dust removal and defluorination integrated sedimentation tank (11).

2. The integrated desulfurization, denitrification, dust removal and defluorination system for kiln tail gas treatment according to claim 1 is characterized in that: The flue gas bag filter (2) is made of woven filter cloth or non-woven felt.

3. The integrated desulfurization, denitrification, dust removal and defluorination system for kiln tail gas treatment according to claim 1 is characterized in that: The steel ladder (3) is arranged on the outside of the flue gas bag filter (2).

4. The integrated desulfurization, denitrification, dust removal and defluorination system for kiln tail gas treatment according to claim 1 is characterized in that: The induced draft fan (5) uses externally input kinetic energy to send the pressurized gas into the defluorination washing tower (6). The model of the induced draft fan (5) is a Y6-30-12 boiler induced draft fan.

5. The integrated desulfurization, denitrification, dust removal and defluorination system for kiln tail gas treatment according to claim 1 is characterized in that: The defluorination washing tower (6) and the desulfurization, denitration, dust removal and defluorination integrated tower (8) adopt a gas-liquid reverse absorption method, that is, the liquid is sprayed downward from the top of the tower in a mist form, and the exhaust gas reaches the purpose of gas-liquid contact through the tower body.

6. The integrated desulfurization, denitrification, dust removal and defluorination system for kiln tail gas treatment according to claim 1 is characterized in that: The wastewater generated in the defluorination washing tower (6) and the desulfurization, denitration, dust removal and defluorination integrated tower (8) is respectively discharged into the defluorination sedimentation tank (7) and the desulfurization, denitration, dust removal and defluorination integrated sedimentation tank (11) for sedimentation, and the treated wastewater is circulated through a circulation pump.

7. The integrated desulfurization, denitrification, dust removal and defluorination system for kiln tail gas treatment according to claim 1 is characterized by: The dust removal and demisting section (9) removes dust and mist from the treated flue gas, and at the same time detects the flue gas after dust removal and demisting. The flue gas that meets the detection standards is discharged into the atmosphere through the chimney direct discharge section (10).

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