Collection of Ultrafine Diesel Particulate Matter (DPM) in Cylindrical Single-Stage Wet Electrostatic Precipitators

Details

• Personal Author:
  Evans DE ; Keener TC ; Khang SJ ; Lu MM ; Saiyasitpanich P ; Evans DE ; Keener TC ; Khang SJ ; Lu MM ; Saiyasitpanich P
• Description:
  Long-term exposures to diesel particulate matter (DPM) emissions are linked to increasing adverse human health effects due to the potential association of DPM with carcinogenicity. Current diesel vehicular particulate emission regulations are based solely upon total mass concentration, albeit it is the submicrometer particles that are highly respirable and the most detrimental to human health. In this study, experiments were performed with a tubular single-stage wet electrostatic precipitator (wESP) to evaluate its performance for the removal of number-based DPM emissions. A nonroad diesel generator utilizing a low sulfur diesel fuel (500 ppm(w)) operating under varying load conditions was used as a stationary DPM emission source. An electrical low-pressure impactor (ELPI) was used to quantify the number concentration distributions of diesel particles in the diluted exhaust gas at each tested condition. The wESP was evaluated with respect to different operational control parameters such as applied voltage, gas residence time, etc., to determine their effect on overall collection efficiency, as well as particle size dependent collection efficiency. The results show that the total DPM number concentrations in the untreated diesel exhaust are in the magnitude of similar to 10(8)/cm(3) at all engine loads with the particle diameter modes between 20 and 40 nm. The measured collection efficiency of the wESP operating at 70 kV based on total particle numbers was 86% at 0 kW engine load and the efficiency decreased to 67% at 75 kW due to a decrease in gas residence time and an increase in particle concentrations. At a constant wESP voltage of 70 kV and at 75 kW engine load, the variation of gas residence time within the wESP from similar to 0.1 to similar to 0.4 s led to a substantial increase in the collection efficiency from 67% to 96%. In addition, collection efficiency was found to be directly related to the applied voltage, with increasing collection efficiency measured for increases in applied voltage. The collection efficiency based on particle size had a minimum for sizes between 20 and 50 nm, but at optimal wESP operating conditions it was possible to remove over 90% of all particle sizes. A comparison of measured and calculated collection efficiencies reveals that the measured values are significantly higher than the predicted values based on the well-known Deutsch equation. [Description provided by NIOSH]
• Subjects:
  Air Pollution Air Pollution, Indoor Environmental Monitoring Occupational Health Particulate Matter Safety Vehicle Emissions
• Keywords:
  Air-quality Air-quality-control Air-quality-measurement Air-quality-monitoring Air-sampling Air-sampling-equipment Air-sampling-techniques Diesel-emissions Filter-materials Filters Gas-filters Gas-sampling Nanotechnology Particulate-sampling-methods Particulates Volumetric-analysis

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• ISSN:
  0013-936X
• Publisher:
  Amer Chemical Soc, 1155 16TH ST, NW, Washington, DC 20036
• Document Type:
  Text
• Funding:
  Grant
• Genre:
  Journal Article ; Journal Article
• Place as Subject:
  Ohio ; OSHA Region 5
• CIO:
  National Institute for Occupational Safety and Health (NIOSH) ; National Institute for Occupational Safety and Health (NIOSH)
• Division:
  DART - Division of Applied Research and Technology ; DART - Division of Applied Research and Technology
• Topic:
  Workplace Safety & Health ; Workplace Safety & Health
• Location:
  North America ; North America
• Volume:
  40
• Issue:
  24
• NIOSHTIC Number:
  nn:20031458
• Citation:
  Environ Sci Technol 2006 Dec; 40(24):7890-7895
• Contact Point Address:
  TC Keener, Univ Cincinnati, Dept Civil & Environm Engn, Cincinnati, OH 45221
• Email:
  Tim.Keener@uc.edu
• Federal Fiscal Year:
  2007
• NORA Priority Area:
  Work Environment and Workforce: Emerging Technologies ; Research Tools and Approaches: Control Technology and Personal Protective Equipment ; Work Environment and Workforce: Emerging Technologies ; Research Tools and Approaches: Control Technology and Personal Protective Equipment
• Performing Organization:
  University of Cincinnati
• Peer Reviewed:
  True
• Start Date:
  20020901
• Source Full Name:
  Environmental Science and Technology
• End Date:
  20060831
• Collection(s):
  National Institute for Occupational Safety and Health
• Main Document Checksum:
  urn:sha-512:b33d0d7a4e89d2b7f7941c819ac920cec332af3f2671ed2e0f2b270512463ce56fa76c12f248c242867af0cfae92550043fa4780ff1986e8cf4754d959b11dc5
• Download URL:
  https://stacks.cdc.gov/view/cdc/185752/cdc_185752_DS1.pdf
• File Type:
  [PDF - 256.90 KB ]