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Show 7 Discussion: The reaction mechanisms used in the composite chemical kinetics model will be extended to include the trace species leading to formation of key air toxics from the combustion of refinery fuel gas and natural gas. Detailed reaction mechanisms for the formation of benzene, ethyl benzene, toluene, and xylene will be developed. Also developed will be semi-empirical mechanisms for the PARs naphthalene, anthracene, and benzo(a)pyrene. The mechanism development will involve the detennination of thermochemical properties and reaction rates of intermediate species leading to the formation of the toxic species. The reaction mechanisms leading to formaldehyde and acetaldehyde formation will be augmented to take into account the fuel-to-air ratios and residence times appropriate to petroleum industry burners. Depending upon the extent to which the toxic species exhibit group behavior, in the latter part of the program the various species will either be grouped into classes according to their response to the combustion environment (temperature, fuel-to-air ratio, mixing, residence time, etc.), or there will be developed detailed reaction mechanisms for selected toxic species beyond those already developed. The list of additional species will be prioritized according to their uniqueness in chemical behavior and their health risk impact. Responsibility: Sandia National Laboratories, Livermore MikstoneslDeliverabks: Sub-mechanisms incorporated for. 8A Butadiene and Benzene (Month 4) 8B Aldehydes and Toluene (Month 12) 8C Ethyl Benzene and Xylene (Month 18) 8D Naphthalene, Anthracene, and Benzo(a)pyrene (Month 24) 8E Preliminary Class Groupings or Advanced-Species (Month 30) 8F Oass Groupings or Advanced Species (Month 33) Task 9. Composite Chemistry Mechanism Development Objective: To develop and incorporate the sub-mechanisms described in Task 8 into the comprehensive chemical kinetics model. Discussion: This task is conducted in parallel with Task 8. As part of this task, the validation measurements of Task 10 will be modeled and further refinements will be made to the submechanisms as necessary. The composite model developed in this task forms the basis of the work to be performed in the integration track. Responsibility: Lawrence Livermore National Laboratory MilestoneslDeliverabks: Sub-mechanisms incorporated for. 9A Butadiene and Benzene (Month 5) 9B Aldehydes and Toluene (Month 15) 9C Ethyl Benzene and Xylene (Month 21) 9D Naphthalene, Anthracene, and Benzo(a)pyrene (Month 27) 9E Preliminary Oass Groupings or Advanced Species (Month 33) 9F Class Groupings or Advanced Species (Month 36) Task 10. Chemistry Validation Measurements Objective: To acquire unambiguous data that can be used directly for validation of the composite chemistry mechanism of Task 9. |
