Method for improving dust removal efficiency of industrial flue gas

Abstract

The invention relates to a method for improving dust removal efficiency of industrial flue gas, and belongs to the technical field of flue gas treatment. Comprising the following steps: pretreating flue gas through a honeycomb catalyst and a denitration reducing agent D; carrying out secondary treatment on the pretreated flue gas by a water vapor injection coupled ultrasonic agglomeration treatment method; the flue gas subjected to secondary treatment enters a high-voltage electrostatic dust collector, and dust in the flue gas passes through the high-voltage electrostatic dust collector; flue gas passes through the first-stage dry-process deacidification mixer and the medium-high temperature SCR reactor; introducing a dry powder deacidification agent to reduce NOx in the flue gas; the flue gas is desulfurized by mixing and matching with ammonia gas and a gypsum desulfurization absorbent through a desulfurization reactor and a secondary dry dust remover; and discharging the desulfurized flue gas through a flue gas outlet. According to the method for improving the dust removal efficiency of the industrial flue gas, the dust removal effect is improved, environmental protection accidents such as smoking are reduced, efficient removal of PM2.5 in the flue gas of the electrostatic dust collector is achieved, and economic, efficient and comprehensive treatment of PM2.5 and SO2 is achieved.

Description

Technical Field

[0001] The invention relates to a method for improving the dust removal efficiency of industrial flue gas, and belongs to the technical field of flue gas treatment. Background Art

[0002] PM2.5 refers to particles with an aerodynamic diameter of less than or equal to 2.5μm. They can enter the human alveoli, so they are also called respirable particles. Due to their small particle size and large specific surface area, they are easily loaded with toxic and harmful substances such as heavy metals (Pb, Zn, As, Hg, etc.), persistent organic pollutants (PCDD / Fs, PCBs, etc.), and pathogens, thus posing a serious threat to human health.

[0003] After long-term operation, the existing dust removal method electrostatic precipitator has problems such as significantly reduced dust removal efficiency, heavy load in the middle area of ​​the plate, and less dust absorption in the periphery. The main reason for this phenomenon is that the converter flue gas cannot be evenly distributed after entering the electrostatic precipitator. Summary of the invention

[0004] In view of this, the present invention provides a method for improving the dust removal efficiency of industrial flue gas, which improves the dust removal effect, reduces the occurrence of environmental accidents such as smoke, realizes the efficient removal of PM2.5 in the flue gas of the electrostatic precipitator, greatly reduces the flue gas treatment volume entering the desulfurization process, and realizes the economical and efficient comprehensive control of PM2.5 and SO2.

[0005] The present invention provides a method for improving the dust removal efficiency of industrial flue gas, which comprises the following steps:

[0006] 1) Pre-treatment of flue gas with denitration reducing agent D through honeycomb catalyst;

[0007] 2) secondary treatment by means of pre-treated flue gas water vapor injection coupled with ultrasonic agglomeration treatment;

[0008] 3) The secondary treated flue gas enters a high-voltage electrostatic precipitator to remove dust from the flue gas;

[0009] 4) The primary dry deacidification mixer, the medium and high temperature SCR reactor are sequentially connected to the high-voltage electrostatic precipitator, and the flue gas passes through the primary dry deacidification mixer and the medium and high temperature SCR reactor;

[0010] 5) Reduce NOx in flue gas by injecting dry powder deacidification agent;

[0011] 6) Desulfurizing the flue gas by mixing with ammonia and gypsum desulfurization absorbent through a desulfurization reactor and a secondary dry dust collector;

[0012] 7) The desulfurized flue gas is discharged through the exhaust port.

[0013] Preferably, the honeycomb catalyst in step 1) comprises 8TiO2-SiO2, V2O5, and WO3, wherein V2O5 and WO3 are active components.

[0014] Preferably, in step 2), the water vapor is sprayed in reverse at a certain angle to the flue gas flow direction, the injection amount of the water vapor is 0.03-0.08 kg / m3, and the temperature of the water vapor is 110-130°C.

[0015] Preferably, in step 2), the frequency of the ultrasound is selected to be 40 kHz-50 kHz, and the power of the ultrasound is 120 W-240 W.

[0016] Preferably, in the step 3), a plurality of conical flue gas distribution plates are expanded at the flue gas inlet of the high-voltage electrostatic precipitator, the large mouth of the conical flue gas distribution plate faces the inside of the high-voltage electrostatic precipitator, and the cone angle of the conical flue gas distribution plate is 120°-160°.

[0017] Preferably, the deacidifying agent in the primary dry deacidifying mixer in step 4) is CaO dry powder or Ca(OH)2 slurry, and the pH value is 4-5.

[0018] Preferably, in step 6), the gypsum desulfurization absorbent is a solid slurry composed of CaCO3, MgCO3, MnSO4, adipic acid and succinic acid.

[0019] Beneficial effects of the present invention:

[0020] The present invention provides a method for improving the dust removal efficiency of industrial flue gas, which improves the dust removal effect, reduces the occurrence of environmental accidents such as smoke, realizes the efficient removal of PM2.5 in the flue gas of the electrostatic precipitator, greatly reduces the flue gas treatment volume entering the desulfurization process, and realizes the economical and efficient comprehensive control of PM2.5 and SO2. DETAILED DESCRIPTION

[0021] The preferred embodiments of the present invention will be described in detail below.

[0022] The present invention provides a method for improving the dust removal efficiency of industrial flue gas, which comprises the following steps:

[0023] 20 parts of crystal raw materials, 18 parts of bamboo raw materials, 10 parts of PVC resin powder, 5 parts of toughening agent, 8 parts of chlorinated polyethylene, 3 parts of phthalamidine hydrochloride, 5 parts of thioterephthalamide, 5 parts of ammonium sulfide aqueous solution, and 3 parts of dilute hydrochloric acid.

[0024] It includes the following steps:

[0025] 1) Pre-treating the flue gas with denitration reducing agent D through a honeycomb catalyst, wherein the honeycomb catalyst comprises 8TiO2-SiO2, V2O5, and WO3, wherein the V2O5 and WO3 are active components;

[0026] 2) The pre-treated flue gas is subjected to secondary treatment by means of water vapor injection coupled with ultrasonic agglomeration treatment, the water vapor injection amount is 0.03-0.08 kg / m3, the water vapor temperature is 110-130°C, the ultrasonic frequency is selected to be 40kHZ-50kHZ, and the ultrasonic power is 120W-240W;

[0027] 3) The secondary treated flue gas enters the high-voltage electrostatic precipitator, and the dust in the flue gas of the high-voltage electrostatic precipitator is passed through, and a plurality of conical flue gas distribution plates are expanded at the flue gas inlet of the high-voltage electrostatic precipitator, and the large mouth end of the conical flue gas distribution plate faces the inside of the high-voltage electrostatic precipitator, and the cone angle of the conical flue gas distribution plate is 120°-160°;

[0028] 4) The primary dry deacidification mixer and the medium-high temperature SCR reactor are connected to the high-voltage electrostatic precipitator in sequence, and the flue gas passes through the primary dry deacidification mixer and the medium-high temperature SCR reactor. The deacidification agent in the primary dry deacidification mixer is CaO dry powder or Ca(OH)2 slurry, and the pH value is 4-5. The flue gas is deacidified by the deacidification agent;

[0029] 5) Reduce NOx in flue gas by injecting dry powder deacidification agent;

[0030] 6) Desulfurizing the flue gas by mixing with ammonia and gypsum desulfurization absorbent through a desulfurization reactor and a secondary dry dust collector. The gypsum desulfurization absorbent is a solid slurry composed of CaCO3, MgCO3, MnSO4, adipic acid and succinic acid;

[0031] 7) The desulfurized flue gas is discharged through the exhaust port.

[0032] The present invention and its implementation methods are described above, and such description is not restrictive, and the actual structure is not limited thereto. In short, if ordinary technicians in the field are inspired by it, without departing from the purpose of the invention, they can design a structure and implementation method similar to the technical solution without creativity, which should all fall within the protection scope of the present invention.

Claims

1. A method for improving the dust removal efficiency of industrial flue gas, characterized in that: The following steps are involved: 1) Pre-treatment of flue gas with denitration reducing agent D through honeycomb catalyst; 2) secondary treatment by means of pre-treated flue gas water vapor injection coupled with ultrasonic agglomeration treatment; 3) The secondary treated flue gas enters a high-voltage electrostatic precipitator to remove dust from the flue gas; 4) The primary dry deacidification mixer and the medium and high temperature SCR reactor are connected to the high-voltage electrostatic precipitator in sequence, and the flue gas passes through the primary dry deacidification mixer and the medium and high temperature SCR reactor; 5) Reduce NOx in flue gas by injecting dry powder deacidification agent; 6) Desulfurizing the flue gas by mixing with ammonia and gypsum desulfurization absorbent through a desulfurization reactor and a secondary dry dust collector; 7) The desulfurized flue gas is discharged through the exhaust port.

2. A method for improving dust removal efficiency of industrial flue gas according to claim 1, characterized in that: In the step 1), the honeycomb catalyst comprises 8TiO2-SiO2, V2O5 and WO3, wherein V2O5 and WO3 are active components.

3. A method for improving dust removal efficiency of industrial flue gas according to claim 1, characterized in that: In the step 2), the water vapor is sprayed in reverse at a certain angle to the flue gas flow direction, the injection amount of the water vapor is 0.03-0.08 kg / m3, and the temperature of the water vapor is 110-130°C.

4. A method for improving dust removal efficiency of industrial flue gas according to claim 1, characterized in that: In the step 2), the frequency of the ultrasonic wave is selected to be 40kHZ-50kHZ, and the power of the ultrasonic wave is 120W-240W.

5. The method for improving the dust removal efficiency of industrial flue gas according to claim 1, characterized in that: In the step 3), a plurality of conical flue gas distribution plates are expanded at the flue gas inlet of the high-voltage electrostatic precipitator, and the large mouth of the conical flue gas distribution plate faces the inside of the high-voltage electrostatic precipitator. The cone angle of the conical flue gas distribution plate is 120°-160°.

6. A method for improving dust removal efficiency of industrial flue gas according to claim 1, characterized in that: The deacidifying agent in the primary dry deacidifying mixer in step 4) is CaO dry powder or Ca(OH)2 slurry, and the pH value is 4-5.

7. A method for improving dust removal efficiency of industrial flue gas according to claim 1, characterized in that: In the step 6), the gypsum desulfurization absorbent is a solid slurry made of CaCO3, MgCO3, MnSO4, adipic acid and succinic acid.