Hazardous Metals in Particulate Matter: Minimizing Risk through Determination of Processes Governing Metal TransformationEPA Grant Number: F6A10020
Title: Hazardous Metals in Particulate Matter: Minimizing Risk through Determination of Processes Governing Metal Transformation
Investigators: Smith, Clara A.
Institution: Dartmouth College
EPA Project Officer: Lee, Sonja
Project Period: September 1, 2006 through September 1, 2009
Project Amount: $111,172
RFA: STAR Graduate Fellowships (2006) RFA Text | Recipients Lists
Research Category: Academic Fellowships , Fellowship - Environmental Engineering , Particulate Matter , Engineering and Environmental Chemistry
I intend to address the homogeneous and heterogeneous chemistry of mercury (Hg) in combustion systems, as well as the potential surface reactions of metals such as antimony or arsenic as they associate with formed particulate matter.
The long term goal of this fundamental research is to reduce the toxicity of any hazardous metals associated with combustion-derived particulate matter by providing fundamental understanding that could potentially be used to modify processes and drive the metals to their less hazardous forms. Even if modification is not feasible, such understanding could permit a facility to choose operating conditions or fuels that produce less hazardous pollutants or PM emissions.
To understand the reactions and transformations occurring in combustion systems several tasks will be performed. Fly ash of varying compositions will be generated to simulate particulate matter produced by a range of fuels in combustion systems. Three different types of reaction rates will then be measured or estimated at combustion temperatures: the reactions of toxic metals with gas constituents, the condensation of the trace metals onto particulate, and gas-solid surface reactions. A dynamic model will then be produced to incorporate the data gathered and describe the reactions occurring in the exhaust of combustion systems.
Once these tasks are completed, we will have a better understanding of the chemical and physical transformations that occur to produce emissions of trace metals and particulate. This information can be used to promote a favored reaction occurring in the exhaust gases, which reduces toxic metal and particulate matter pollution or makes the pollutants more easily captured. By examining the effects of temperature and flue gas constituents on the process we will have a useful tool for applying the results of this work to processes in industry.