Title: Environmental chamber experiments and CMAQ modeling to improve mechanisms to model ozone formation from HRVOCs
Institution(s) Represented: University of California - Riverside - Gookyoung Heo, Texas A&M University - Qi Ying
Lead PI: Gookyoung Heo
AQRP Project Manager: Elena McDonald-Buller
TCEQ Project Liaison: Ron Thomas
Awarded Amount: $146,259.00
Abstract
Environmental chamber experiments and CMAQ modeling to improve mechanisms to model ozone formation from HRVOCs
Using reliable atmospheric chemical mechanisms in regulatory models is necessary to formulate effective air quality policies for controls of secondary air pollutants such as ozone (O3). It is well known that alkenes are a major contributor to radical and O3 formation in Southeast Texas due to their high emissions and their high reactivities. Particularly, in Harris County, Texas, seven alkenes (ethene, propene, 1,3-butadiene, 1-butene, isobutene, trans-2-butene, and cis-2-butene) are classified as Highly Reactive Volatile Organic Compounds (HRVOCs), and HRVOC emissions have been regulated by Texas Administrative Code, Title 30, Part 1, Chapter 115 (TCEQ, 2102).
However, condensed chemical mechanisms commonly used for air quality modeling in the U.S. are designed to model O3 formation from typical urban ambient volatile organic compound (VOC) mixtures but are not designed to model O3 formation under atmospheric conditions significantly influenced by highly variable HRVOC emissions that are dominated by a small number of VOC species. Therefore, a chemical mechanism that can be used to simulate O3 formation from both urban emissions and industrial HRVOC emissions needs to be developed to accurately assess the impact on O3 formation of regular and episodic HRVOC emissions from industrial sources in Southeast Texas. However, lack of environmental chamber data useful for mechanism evaluation is a critical obstacle to developing reliable mechanisms for the HRVOCs. Among the 7 alkenes regulated as HRVOCs in Southeast Texas, robust chamber data for mechanism evaluation are available only for ethene and propene. The situation is even worse for the higher molecular weight non-HRVOC alkenes. Thus, this study will develop more robust chemical mechanisms for the HRVOCs and non-HRVOC alkenes that are better suited for use under atmospheric conditions influenced by HRVOC emissions, and evaluate and update the initially proposed mechanisms by designing and carrying out environmental chamber experiments for the HRVOCs and non-HRVOC alkenes for which existing data are inadequate. The effect of the mechanism modifications on air quality predictions in Southeast Texas will be evaluated by carrying out 3-dimensional air quality modeling with the Community Multiscale Air Quality modeling system (CMAQ), using both existing mechanisms and the updated and more explicit mechanisms developed in this work.
Executive Summary: projectinfoFY12_13\12-006\12-006 Executive Summary.pdf
Work Plan: projectinfoFY12_13\12-006\12-006 Work Plan.pdf
Technical Report(s): projectinfoFY12_13\12-006\12-006 Feb 2013 MTR.pdf
Technical Report(s): projectinfoFY12_13\12-006\12-006 Mar 2013 MTR.pdf
Technical Report(s): projectinfoFY12_13\12-006\12-006 Apr 2013 MTR.pdf
Technical Report(s): projectinfoFY12_13\12-006\12-006 May 2013 MTR.pdf
Technical Report(s): projectinfoFY12_13\12-006\12-006 Jun 2013 MTR.pdf
Technical Report(s): projectinfoFY12_13\12-006\12-006 Jul 2013 MTR.pdf
Technical Report(s): projectinfoFY12_13\12-006\12-006 Aug 2013 MTR.pdf
Technical Report(s): projectinfoFY12_13\12-006\12-006 Sep 2013 MTR.pdf
QAPP: projectinfoFY12_13\12-006\12-006 QAPP.pdf
Final Report: projectinfoFY12_13\12-006\12-006 Final Report.pdf
Publications & Citations
Journal Papers: Gookyoung Heo, Peng Wang, Qi Ying, Ron Thomas, William P.L. Carter. Using chemically detailed emissions data to test assumptions used in developing chemical mechanisms: a case study for southeast Texas, USA. [To be submitted to Atmospheric Environment in Summer 2014] Peng Wang, Gookyoung Heo, William P.L. Carter, Qi Ying. Comparison of a detailed and a lumped version of SAPRC-11 photochemical mechanism during a summer ozone episode. [To be submitted to Atmospheric Environment in Summer 2014] Gookyoung Heo, Chia-Li Chen, Ping Tang, William P.L. Carter. Evaluation of mechanisms for major terminal and internal alkenes with environmental chamber data. [To be submitted to Atmospheric Environment in Summer 2014] Gookyoung Heo, Shunsuke Nakao, William P.L. Carter. Evaluation of mechanisms for 1,3-butadiene with environmental chamber data. [To be submitted to Atmospheric Environment in Summer 2014] Conference Paper: Heo, G., Carter, W.P.L., Wang, P., Ying, Q., Thomas, R. (2013). Evaluating and improving atmospheric chemical mechanisms used for modeling ozone formation from alkenes. Presented at the 12th Annual CMAS Conference, Chapel Hill, NC, October 28-30, 2013.
