CN202757917U - Device for detecting oxidation capacity of denitration system catalysts for elemental mercury - Google Patents

Abstract

A device for detecting the oxidation capacity of denitration system catalysts of a coal-fired power plant for elemental mercury comprises a gas distributing system, an electric heater, a first catalyst tank, a second catalyst tank, a third catalyst tank, an activated carbon adsorption tank, an induced draft fan, a first stop valve, a waste gas treatment device and a first pressure release valve which are sequentially connected. An air compressors is connected to the front and the back of the electric heater through two branches, flue gas sampling points are arranged on an inlet pipeline and an outlet pipeline in the front and at the back of each catalyst tank, a second pressure release valve and a gas component detecting meter are further arranged on a front pipeline of the first catalyst tank, a computer is connected outside the gas component detecting meter, bypasses are arranged on a front pipeline and a rear pipeline of the third catalyst tank, and a second bypass valve is arranged on each bypass. The utility model further relates to a use method of the device. The capacity of the denitration system catalysts of the coal-fired power plant for oxidizing the elemental mercury in flue gas into divalent mercury can be analyzed to provide data support for evaluating the concentration of mercury finally discharged into air by the coal-fired power plant. The oxidation capacity of the catalysts for the elemental mercury can be monitored at regular intervals, and a basis is provided for the power plant to take mercury emission reduction and control measures.

Description

For detection of the device of denitrating system catalyzer to the Elemental Mercury oxidability

Technical field

The utility model relates to a kind of for detection of coal-burning power plant's denitrating system catalyst oxidation Elemental Mercury--nonvalent mercury in the flue gas is oxidized to the device of divalence mercury ability.

Background technology

At present; national environmental protection section and State Administration for Quality Supervision and Inspection and Quarantine unite and have issued the GB13223-2011 fossil-fuel power plant atmospheric pollutant emission standard; standard is really stipulated: from 1 day January in 2015, the mercury and mercuric compounds pollutant emission limit of table 1 regulation (was no more than 30 μ g/Nm in the coal-burning boiler execute file ³).Therefore, how the reduction of discharging measure of rational mercury in flue gas is most important to coal-fired station, is related to economy of power plant and environmental protection characteristic.Most of coal-fired unit has all been equipped denitrating system or has been prepared to install denitrating system, from present achievement in research both domestic and external, the catalyzer of flue gas denitrification system has oxidation to the nonvalent mercury in the flue gas, can be oxidized to divalence mercury to nonvalent mercury, can reduce the discharging of chimney of electric plant mercury in flue gas by flue gas desulphurization system to mercuric dissolving.

The utility model content

Technical problem to be solved in the utility model just provides a kind of for detection of coal-burning power plant's denitrating system catalyst oxidation Elemental Mercury--nonvalent mercury in the flue gas is oxidized to the device of divalence mercury ability.

Solve the technical problem, the technical solution adopted in the utility model is:

A kind of device for detection of coal-burning power plant's denitrating system catalyst oxidation Elemental Mercury is characterized in that comprising:

The gas distributing system, electric heater, the first catalyst tank, the second catalyst tank, the 3rd catalyst tank, absorbent charcoal adsorber, induced draft fan, the first stop valve, emission-control equipment and the first blowdown valve that connect successively with pipeline;

Other has air compressor machine through being connected to by two branches on the pipeline of described electric heater front and back behind the gas-holder, and branch one is provided with ash storage box and first flow operation valve, and branch two is provided with the first bypass valve;

Import and export pipeline before and after described each catalyst tank is provided with the smoke sampling point, also be provided with the second blowdown valve and gas composition detection table on the first catalyst tank preceding pipeline, gas componant detects off-balancesheet and is connected with computing machine, pipeline before and after the 3rd catalyst tank is provided with bypass, and bypass is provided with the second bypass valve.

Described gas distributing system includes SO ₂, N ₂, O ₂, NO, nonvalent mercury steam calibrating gas tank, be respectively equipped with the second to the 7th flowrate control valve on the outlet conduit of each tank, each outlet conduit converges at last a distribution house steward and is connected to the 8th flowrate control valve and tensimeter.

Described air compressor machine output channel is provided with the 9th flowrate control valve, and the porch of described branch one is provided with the tenth flowrate control valve.

The principle of the technical solution of the utility model is utilized N exactly ₂, O ₂, NO, SO ₂, nonvalent mercury steam calibrating gas carries out distribution, and adds the flying dust fetched the coal-burning power plant (bottom flue perforate when flying dust utilizes is blown into the method for flue with pressurized air); The true component of simulation fire coal boiler fume, the flow velocity of control gas is about 8-10m/s, and the concentration of ash is controlled at 10-12g/Nm in the mixed gas ³Then allow mixed gas be heated to 330-350 ℃ by heating arrangement, the mixed gas after the heating is successively by 2 layers of catalyzer, totally 3 layers of catalyzer casings, and 2 usefulness 1 are standby, are consistent with the truth of power plant.All arrange the smoke sampling gaging hole at every layer of catalyst inlet and outlet, be used for extracting flue gas, analyze the content of mercury in flue gas and the conversion situation of valence state.

Adopt the OHM method to test the content (comprising nonvalent mercury, divalence mercury, particle mercury) of each sampling spot mercury in flue gas.This device arranges the pressure on-Line Monitor Device, and blowdown valve has been installed, and reacted tail gas absorbs by waste gas recovering device to be processed, and has guaranteed safety in the testing process, environmental protection.

This device can be achieved as follows function:

(1) can detect the different catalysts activity nonvalent mercury is oxidized to mercuric ability;

(2) can detect the different catalysts number of plies nonvalent mercury is oxidized to mercuric ability;

(3) can detect different flue-gas temperatures to the capacity degree of catalyst oxidation nonvalent mercury;

(4) can detect different exhaust gas components to the capacity degree of catalyst oxidation nonvalent mercury;

(5) can detect in the flue gas different ash concentrations to the capacity degree of catalyst oxidation nonvalent mercury.

Beneficial effect: these apparatus and method can be used for analyzing coal-burning power plant's denitrating system catalyzer nonvalent mercury in the flue gas are oxidized to mercuric ability, and the concentration that is used for finally being discharged into for the assessment coal-burning power plant air-borne mercury improves Data support.By using this method and device, can regularly carry out the monitoring of catalyst oxidation Elemental Mercury ability, mercury reduces discharging and control measure provide foundation for power plant formulates.

Description of drawings

Fig. 1 is the composition structural representation of the device embodiment for detection of coal-burning power plant's denitrating system catalyst oxidation Elemental Mercury of the present utility model.

Embodiment

As shown in drawings, device for detection of coal-burning power plant's denitrating system catalyst oxidation Elemental Mercury of the present utility model comprises the gas distributing system 1, electric heater 2, the first catalyst tank 3, the second catalyst tank 4, the 3rd catalyst tank 5, absorbent charcoal adsorber 6, induced draft fan 7, the first stop valve 8, emission-control equipment 9 and the first blowdown valve 10 that connect successively with pipeline.

Gas distributing system 1 includes SO ₂, N ₂, O ₂, NO, nonvalent mercury steam calibrating gas tank, be respectively equipped with the second to the 7th flowrate control valve 23,24,25,26,27 on the outlet conduit of each tank, each outlet conduit of flowrate control valve converges at last a distribution house steward and is connected to the 8th flowrate control valve 28 and tensimeter 29.

Other has air compressor machine 11 through being connected on the pipeline of electric heater 2 front and back by two branches behind the gas-holder 12, and branch one is provided with ash storage box 13 and first flow operation valve 14, and branch two is provided with the first bypass valve 15.

Import and export pipeline before and after each catalyst tank is provided with smoke sampling point 16,17,18,32, also be provided with the second blowdown valve 19 and gas composition detection table 20 on the first catalyst tank preceding pipeline, gas componant detects off-balancesheet and is connected with computing machine 21, pipeline before and after the 3rd catalyst tank is provided with bypass, and bypass is provided with the second bypass valve 22.The air compressor machine output channel is provided with the 9th flowrate control valve 30, and the porch of branch one is provided with the tenth flowrate control valve 31.

Use said apparatus for detection of the method for coal-burning power plant's denitrating system catalyst oxidation Elemental Mercury, may further comprise the steps:

Step 1: the inspection of device tightness, utilize pressurized air, make device pressure be increased to 0.1MPa, utilize soap bubble to carry out leakage detection;

Step 2: logical pressurized air, and drop into heating arrangement, be heated to 330 ℃-350 ℃, and keep stable; Carry out hot tightness inspection;

Step 3: require to carry out distribution according to different tests, and from the on-line monitoring instrument real-time reading, adjust gas flow by the needle valve of adjusting the outlet of calibrating gas gas cylinder, thereby the concentration of this component gases in the change mixed gas, the flow velocity of control gas is at 8-10m/s, and the concentration of ash is controlled at 10-12g/Nm in the mixed gas ³Then allow mixed gas be heated to 330-350 ℃ by heating arrangement;

Step 4: after gas concentration is stable, import and export the sampling of smoke sampling point from catalyzer, the content (comprising nonvalent mercury, divalence mercury, particle mercury) of test mercury in flue gas;

Step 5: after test finishes, at first stop the flue gas heater power supply, and close the valve of all calibrating gas gas-holder outlets, stop simultaneously flying dust and supply with, device passes into pressurized air and purges until the heater outlet temperature is lower than 40 ℃, stops the pressurized air supply; Device is finished using.

Computing method:

${\mathrm{\η}}_{\mathrm{total}}=\frac{{\mathrm{Hg}}_{2-3\mathrm{out}}}{{\mathrm{Hg}}_{0-1\mathrm{in}}}$

${\mathrm{\η}}_1=\frac{{\mathrm{Hg}}_{2-1\mathrm{out}}}{{\mathrm{Hg}}_{0-1\mathrm{in}}}$

${\mathrm{\η}}_2=\frac{{\mathrm{Hg}}_{2-2\mathrm{out}}-{\mathrm{Hg}}_{2-1\mathrm{out}}}{{\mathrm{Hg}}_{0-2\mathrm{in}}}$

${\mathrm{\η}}_3=\frac{{\mathrm{Hg}}_{2-3\mathrm{out}}-{\mathrm{Hg}}_{2-2\mathrm{out}}}{{\mathrm{Hg}}_{0-3\mathrm{in}}}$

Wherein:

η _Total-expression flue gas through 3 layers of catalyzer after nonvalent mercury be converted into mercuric total conversion, %;

η ₁Nonvalent mercury is converted into mercuric conversion ratio, % behind the-expression flue gas process ground floor catalyzer;

η ₂Nonvalent mercury is converted into mercuric conversion ratio, % behind the-expression flue gas process second layer catalyzer;

η ₃Nonvalent mercury is converted into mercuric conversion ratio, % behind the-expression flue gas process second layer catalyzer;

Hg _0-1inThe concentration of-expression ground floor catalyst inlet nonvalent mercury, mg/Nm ³

Hg _0-2inThe concentration of-expression second layer catalyst inlet nonvalent mercury, mg/Nm ³

Hg _0-3inThe concentration of the 3rd layer of catalyst inlet nonvalent mercury of-expression, mg/Nm ³

Hg _2-1outThe mercuric concentration of-expression ground floor catalyst outlet, mg/Nm ³

Hg _2-2outThe mercuric concentration of-expression second layer catalyst outlet, mg/Nm ³

Hg _2-3outThe 3rd layer of mercuric concentration of catalyst outlet of-expression, mg/Nm ³

Claims (3)

1. one kind for detection of the device of denitrating system catalyzer to the Elemental Mercury oxidability, it is characterized in that: comprise the gas distributing system, electric heater, the first catalyst tank, the second catalyst tank, the 3rd catalyst tank, absorbent charcoal adsorber, induced draft fan, the first stop valve, emission-control equipment and the first blowdown valve that connect successively with pipeline;

Other has air compressor machine through being connected to by two branches on the pipeline of described electric heater front and back behind the gas-holder, and branch one is provided with ash storage box and first flow operation valve, and branch two is provided with the first bypass valve;

Import and export pipeline before and after described each catalyst tank is provided with the smoke sampling point, also be provided with the second blowdown valve and gas composition detection table on the first catalyst tank preceding pipeline, gas componant detects off-balancesheet and is connected with computing machine, pipeline before and after the 3rd catalyst tank is provided with bypass, and bypass is provided with the second bypass valve.

2. according to claim 1 for detection of the device of denitrating system catalyzer to the Elemental Mercury oxidability, it is characterized in that: described gas distributing system includes SO ₂, N ₂, O ₂, NO, nonvalent mercury steam calibrating gas tank, be respectively equipped with the second to the 7th flowrate control valve on the outlet conduit of each tank, each outlet conduit converges at last a distribution house steward and is connected to the 8th flowrate control valve and tensimeter.

3. according to claim 2 for detection of the device of denitrating system catalyzer to the Elemental Mercury oxidability, it is characterized in that: described air compressor machine output channel is provided with the 9th flowrate control valve, and the porch of described branch one is provided with the tenth flowrate control valve.