Characteristics of Inhalable Particulate Matter Concentration and Size Distribution from Power Plants in China

Abstract

In this investigation, the collection efficiency of particulate emission control devices (PECDs), particulate matter (PM) emissions, and PM size distribution were determined experimentally at the inlet and outlet of PECDs at five coal-fired power plants. Different boilers, coals, and PECDs are used in these power plants. Measurement in situ was performed by an electrical low-pressure impactor with a sampling system, which consisted of an isokinetic sampler probe, precut cyclone, and two-stage dilution system with a sample line to the instruments. The size distribution was measured over a range from 0.03 to 10 m. Before and after all of the PECDs, the particle number size distributions display a bimodal distribution. The PM 2.5 fraction emitted to atmosphere includes a significant amount of the mass from the coarse particle mode. The controlled and uncontrolled emission factors of total PM, inhalable PM (PM 10 ), and fine PM P(M 2.5 ) were obtained. Electrostatic precipitator (ESP) and baghouse total collection efficiencies are 96.38 -99.89% and 99.94%, respectively. The minimum collection efficiency of the ESP and the baghouse both appear in the particle size range of 0.1-1 m. In this size range, ESP and baghouse collection efficiencies are 85.79 -98.6% and 99.54%. Real-time measurement shows that the mass and number concentration of PM 10 will be greatly affected by the operating conditions of the PECDs. The number of emitted particles increases with increasing boiler load level because of higher combustion temperature. During test run periods, the data reproducibility is satisfactory. INTRODUCTIONInhalable particulate matter (PM 10 ) is one of the principal pollutants of the urban air in China 1 and is also a main contributor for other pollution phenomena, such as visibility degradation and global climate change. Furthermore, fine particulate matter (PM 2.5 ) and ultrafine particle matter are more harmful to human health than coarse particles. 2 Many indicators of health impacts have a close relationship with the time of exposure to certain concentrations of fine particles. 3 Most PM 10 in the atmosphere comes from power plants, vehicles, and other combustion sources and is usually associated with significant toxic matter. 4 Coal is the major energy source in China and, even in 2020, will account for 54% of total energy consumption. 5 In our country, ϳ80% of coal is consumed by direct combustion. Most of this is consumed by power plants (ϳ45% of total coal consumption today and predicted to increase to 62% in 2010). The electric power industry accounts for the highest emissions of smoke and dust among all industries. 6 The particulate matter (PM) emitted from coal combustion is becoming an important research topic in China. Historically, particulate emission control mainly dealt with the reduction of the mass of the PM released into the atmosphere. However, an estimate for the number concentration of primary combustion aerosol particles demonstrates the potential importance of such anthropogenic source...

Emission Characteristics and Control Prospects of Primary PM2.5 from Fossil Fuel Power Plants in China

“…The EFs of PM 2.5 were calculated using Eqs. (5)- (7), and the variables were compiled from the available references and official published reports (Yi et al, 2006;Zhao et al, 2008;Wang et al, 2010a;MEP, 2014b).…”

“…The PM 2.5 removal efficiencies of different technologies were averaged; the results were approximately 92.6% for ESPs, 97.5% for the combination of ESPs + Wet-FGD, and 99.0% for FFs (Yi et al, 2006;Zhao et al, 2008;Zhao et al, 2010;MEP, 2014a). It was estimated that SCR installation can increase primary PM 2.5 emissions by at least 20.0% in comparison with the combination of ESPs + FGD .…”

Design of a Compact Dilution Sampler for Stationary Combustion Sources

“…6 Only a few researchers conducted studied on PM 10 or PM 2.5 emissions from limited sources. [23][24][25][26] Official air pollutant emission statistical data reported PM, but did not refer to PM 10 and PM 2.5 . 27 Zhang et al estimated Chinese PM (including PM 10 and PM 2.5 ) emissions.…”

“…These analysis methods have been described in our earlier papers 36,37 and are briefly summarized here. Teflon-membrane filters were conditioned for 24 hr at about 40% relative humidity (RH) and 25 C in an air-conditioned room and weighed on a microbalance with a resolution 10 mg. Elements were analyzed by inductively coupled plasma optic emission spectrometry (ICP-OES; IRIS Intrepid II XSP, Thermo, Waltham, USA).…”

Capture of Particles from an Iron and Steel Smelter with a Pulse-Energized Electrostatic Precipitator

“…Significant effort has been devoted to the improvement of collection performance of the ESPs in various applications (Zhuang et al, 2000;Li and Wen, 2003;Lind et al, 2006;Yi et al, 2006;Sharma et al, 2007;Guerriero et al, 2008;Saiyasitpanich et al, 2008;Ivancsy et al, 2009;Ruttanachot et al, 2011). In addition, several modified ESPs were also developed and reported in literature, such as electrostatic flocking (Sung et al, 2006), wet electrostatic precipitators (Saiyasitpanich et al, 2006), dielectric barrier discharge (Byeon et al, 2006), plasma enhanced precipitator (Montgomery et al, 2005), soft X-ray-enhanced corona systems (Kulkarni et al, 2002;Hogan et al, 2004;Jiang et al, 2007), simultaneous diffusional-electrostatic precipitation (Alonso et al, 2002), and pulse-energized electrostatic precipitation (Dinelli et al, 1991;Jayaram et al, 1996;Mok et al, 1999;Zukeran et al, 1999a;Liang et al, 2002a;2002b).…”