1 / 9

AIR QUALITY AND ETHANOL

AIR QUALITY AND ETHANOL. Gary Z. Whitten. INTRODUCTION. Ethanol impacts both positive and negative Ethanol similar to but not MTBE Trade-off’s can be complex Not readily acceptable due to Regulations Agencies Oil companies And sometimes environmental groups.

guang
Download Presentation

AIR QUALITY AND ETHANOL

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript


  1. AIR QUALITY AND ETHANOL Gary Z. Whitten

  2. INTRODUCTION • Ethanol impacts both positive and negative • Ethanol similar to but not MTBE • Trade-off’s can be complex • Not readily acceptable due to • Regulations • Agencies • Oil companies • And sometimes environmental groups

  3. Carbon Monoxide, Ozone, Toxics, and PM • CO makes ozone • Toxics are closely regulated and adjusted in RFG • PM needs more recognition

  4. Carbon monoxide makes ozone • 1974 paper “just CO and NOx might exceed ozone standard.” • 1988 testimony “1 pound waiver mainly due to CO reduction by ethanol.” • 1998 NRC study “credit for CO reduction should be in RFG.”

  5. Toxics are closely regulated in RFG • Ethanol can reduce benzene by 30 percent • Dilution • Octane substitute for aromatics • Cleaner burning • Refiners often can adjust benzene for RFG • Acetaldehyde increased by ethanol, but several studies show this is not a problem

  6. PM needs more recognition • Science of PM rapidly emerging • PM can be primary or secondary • Ethanol significantly reduces both • Secondary (man-made)may be essentially all from aromatics • Ethanol impact similar to benzene

  7. Ozone Trade-offs • CO reduction equal to at least 3% of VOC • This is for RFG going from 2% to 3.5% oxygen • For non-oxy the full credit could be 7% • Aggressive driving, high emitters, old cars, and off-road engines also show VOC benefits • Unfortunately, regulations based mainly on data from low-emitting vehicles show much VOC benefit

  8. Trade-offs (Cont.) • Recent data (1999) show 63% of CO and 47% of VOC coming from 10% of vehicles • ARB tests show aggressive driving (REP05) • Ethanol (vs MTBE) showed 3% benefit in normal driving (FTP) but 10% when REP05 data included. • Complex Model for RFG and ARB model both all based on FTP (no REP05 data)

  9. Trade-offs (cont.) • EPA tests on 36 vehicle fleet (half higher emitters) show 6% CO reduction and 4% VOC reduction with ethanol (vs, MTBE), but all the benefits came from the higher emitters. • Note only FTP data here (no REP05) • Grid model tests show • CO major (33% of ozone) impact • Exhaust VOC more important than evaps.

More Related