Emissions from petroleum and chemical process industries (PCPI) is still one of the root causes of transient and localized high-ozone issues in several Texas industrial regions such as Houston-Galveston-Brazoria (HGB), Beaumont-Port Arthur (BPA), and Corpus Christi areas. However, emission reductions at PCPI plants generally need additional facilities and extra operating steps with more energy and material consumptions than before. This will result in substantial capital and operating costs that would impose a heavy economic burden to PCPI plants. Therefore, emission reduction and control in PCPI plants must be both environmentally and economically effective. This project consists of multiple research studies is trying to identify both air-quality conscious and cost-effective emission control strategies to not only improve the air quality in general PCPI regions, but also pursue the minimum cost for industrial emission controls, or even possible to award PCPI plants with more profits.
Drs. Qiang Xu and Thomas Ho, Professors, Dan F. Smith Department of Chemical Engineering
This project is fundamentally different from the previous studies, which are generally focused on the end-of-pipe treatment and disposal. It develops a multi-scale and multi-perspective methodology by integrating industrial process and regional air-quality modeling, simulation, and optimization. First, in the process scale of PCPI plants, possible candidates under normal and abnormal conditions (e.g., startup, shutdown, and process upset) will be investigated. This will also help obtain the dynamic information of benchmark emissions from PCPI plants emitted to the atmospheric environment. The dynamic information includes emission species, flowrates, and time durations. Next, in the regional scale, air-quality modeling and simulations will be performed to study potential dynamic changes of the 8-hr ozone concentration in PCPI areas due to the implementation of emission control candidates. The TCEQ ozone episodes will be employed for the CAMx based air-quality modeling and simulation. Both process simulation and air-quality simulation will help obtain the ozone impact corresponding to the studied ACCESC candidates. Iteratively, all possible ACCESC candidates will be quantitatively evaluated via this multi-scale modeling and simulation method. Through this project, scientific support information will be provided to all air-quality stakeholders for their decisions on regional and industrial emission controls.
Different project aspects were funded by Texas Commission on Environmental Quality (TCEQ), Texas Air Research Center (TARC), South East Texas Regional Planning Commission.