Detection method and collection device for mercury in waste incineration flue gas

Abstract

The invention relates to the technical field of environmental monitoring, in particular to a method for detecting mercury in waste incineration flue gas, which comprises the following steps: separating particulate mercury and gaseous mercury in flue gas through a filter membrane, and measuring the content of the particulate mercury in the flue gas; introducing the flue gas into a clay mineral solid adsorbent wetted by deionized water, and collecting mercuric oxide in the flue gas; introducing the flue gas into a solid acid adsorbent wetted by deionized water, and collecting the element mercury in the flue gas; heating and desorpting the clay mineral solid adsorbent and the solid acid adsorbent to respectively measure the content of mercuric oxide and the content of elemental mercury. The invention further relates to a collecting device which comprises a constant-temperature sampling gun and a constant-temperature adsorption bottle box, wherein a constant-temperature filter is arranged in the constant-temperature sampling gun; a first bottle body filled with a clay mineral solid adsorbent and a second bottle body filled with a solid acid adsorbent are sequentially communicated in the constant-temperature adsorption bottle box in the flue gas flowing direction. The device is suitable for a high-temperature, high-humidity and high-corrosion flue gas detection environment, and the higher the temperature, humidity and acidity of the flue gas are, the more beneficial to mercury collection of a clay mineral solid adsorbent and a solid acid adsorbent.

Description

technical field [0001] The invention relates to the technical field of environmental monitoring, in particular to a detection method and a collection device for mercury in waste incineration flue gas. Background technique [0002] Mercury is one of the most harmful heavy metals. Due to its refractory degradation and bioaccumulation, the pollution caused by it has attracted increasing attention. Waste incineration is another major source of mercury pollution. The dust, moisture, HCl, SOx and NOx content in the waste incinerator flue gas is high, and the flue gas is high temperature, high humidity, and high corrosion, and the working conditions for flue gas detection are harsh. [0003] Mercury exists in three forms in flue gas, namely elemental mercury Hg 0 , mercury oxide Hg 2+ and particulate mercury Hg p . Hg 0 and Hg 2+ Collectively referred to as gaseous mercury, which exists in flue gas in gaseous form, Hg 0 Insoluble in water and highly volatile, but Hg 0 Can ...

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Problems solved by technology

[0004] The standard mercury sampling method recognized by the U.S. Environmental Protection Agency is to use the solution absorption bottle method for collection. This method has high requirements for testing technology and personnel quality, and has strict requirements for the collection and analysis of gas samples. Flue gas will cause a dilution effect, and the gas flow rate is also easily affected by the dust in the adsorption solution; there are many kinds of reagents, the collection and preliminary preparation work is cumbersome, and the absorption solution needs to be used and prepared immediately, which is not easy to carry and store; the collection time is long, and it is required to collect at least 2h , the instrument analysis is cumbersome, and the analysis results lag behind. It takes 3 to 5 days to get the analysis results

[0005] In my country, activated carbon tubes are mainly used to collect mercury, but activated carbon is easy to absorb other impurities, so it can only be used for purified air; SO in flue gas 2 , NOx will inhibit the capture of mercury by activated carbon, and mercury is easy to penetrate, and the detection repeatability of the device is poor

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