| on the basis of the Ontario hydro method, combined with the method of “determination of mercury emissions from stationary sources by cold atomic absorption spectrophotometry” and “air emission monitoring and analysis methods”, designed a new sampling system, called standard improved method. Ontario hydro method, Standard improved method and EPA method 30 B were used to contrast flue gas mercury testing methods, mercury balance and flue gas mercury emissions research of eight typical coal-fired power plants from Xinjiang. The main conclusions are as follows:(1) Total gaseous mercury monitoring results of Ontario hydro method, Standard improved method and EPA method 30 B were approaching, three methods total mercury balance rate of boiler and electrostatic precipitator were between 75.75%-99.59%, three methods had reliable operation and accurate data.(2) Three kinds of sampling methods can monitored flue gas mercury of power plant. EPA method 30 B were sampling easily and operation fast,laboratory analysis was accurate,it is the preferred method of flue gas mercury compliance testing. However, the sample sorbent tube and the price of special analytical instruments were high.Ontario hydro method and standard improved method of wet field sampling glassware and absorbing liquid were inconvenient to carry, required large sampling platform, sampling and laboratory sample processing steps were complex, poor operability, but the cost of test was low. The sampling and laboratory sample processing steps of standard improved method were relatively simple, Not only for the flue gas mercury detection standards of power plant, but also for the research of flue gas mercury removal of conventional pollutants, Standard improved method can be used as an alternative of EPA method 30 B.(3) The exit flue gas of electrostatic precipitator and desulfurization were gaseous mercury, proportion of elemental mercury were large, particulate mercury were rarely. The mercury content of gypsum and fly ash in relative to the mercury content of desulfurizer, process water, slag and desulfurization wastewater was high. Almost all mercury of coal-fired power plants released into the flue gas.(4)Total mercury and total gaseous mercury contents of ESP and WFGD were less than the emission limit. The mercury content of coal from Xinjiang was low,so the mercury content of coal-fired power plant atmosphere was low.(5)Total mercury emissions intensity of two power plant was(0.77~0.81)×10-12g/J. Compared with the US Department of energy for the nine plant test results(0.82~9.46)×10-12g/J and national test results for two power plants was(2.578~3.428)×10-12g/J, total mercury emissions intensity from Xinjiang power plants were lower.(6)Two plants WFGD total mercury removal rates were 3.87%, 31.79%, total gaseous mercury removal rates were 8.51%, 30.30%, different power plant four ESP electric had different total mercury removal rates.(7) Each power plant mercury residue enrichment factor in dross was less than one, the majority of ash and gypsum mercury enrichment factor were greater than one. For the mercury content and mercury enrichment factor was much larger than one in gypsum and ash should be evaluated after their risk of secondary contamination, and then landfill or as a building material. From mercury content, the various power plant ash and gypsum were general industrial solid waste.(8) The average of the mercury content in regional coal-fired power plants was approaching, and the mercury content of coal-fired power plant in Urumqi and Changji area slightly larger than the Aksu area. When mercury fixative KBr O3 amount increased to 8%, the rate of fixed mercury reached 23.01%,the effect of mercury fixation was better. |
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