Date of Award
Doctor of Philosophy (PhD)
The ultimate fate and chemical kinetics of low-pH hazardous wastes after deep well injection were studied. Two experimental approaches were taken. Chemical kinetics of reactions involving acids and typical formation clays was studied using a batch reaction scheme. The effects of reactions involving flowing acidic waste streams and disposal formations were characterized using sand packs of length one foot, four feet, and twenty feet. A numerical ground water flow simulator was used to model the interactions of flowing acidic wastes with linear sand packs and with a hypothetical waste disposal system. Reaction rate coefficients and activation energies were determined for reactions of hydrochloric acid, nitric acid, and sulfuric acid with sodium montmorillonite, kaolinite, and illite. Reactions were studied at temperature of fifty degrees Celsius (122 degrees Fahrenheit) and seventy degrees Celsius (158 degrees Fahrenheit). Values of rate coefficients and activation energies agree reasonably well with those obtained by a previous investigator using a different experimental approach. Sand pack experimentation provided evidence of the neutralizing effect on acid of typical formation clays. Sand packs containing typical proportions of sodium montmorillonite, illite, and kaolinite were found to have a neutralizing effect on hydrochloric acid, nitric acid, and sulfuric acid. Actual formation material from a waste disposal well in St. Bernard Parish, Louisiana (the "Kaiser" well), was found to neutralize hydrochloric acid. The Kaiser well material was the most effective at neutralizing acid, and kaolinite was the least effective at neutralizing acid. The ground water flow simulator SUTRA was used to simulate flow of acidic fluids through sand packs containing Kaiser well material. Simulated results of one foot, four foot, and twenty foot sand pack runs agree reasonably well with experimental results. SUTRA was used to model a hypothetical but realistic low-pH waste disposal system in which wastes were injected for periods of time up to twenty years.
Aubert, Winton G., "Fate and Transport of Low-Ph Hazardous Materials After Deep Well Disposal." (1986). LSU Historical Dissertations and Theses. 4280.