Effects of Carbonation on the Long-term Leaching Performance of Cementitious Wasteforms
نویسنده
چکیده
Cement-based wasteforms are among the most commonly used waste disposal and site remediation options. However, concrete knowledge of the processes controlling long-term performance of the wasteforms is lacking. This research evaluates the effect of carbonation on cementitious wasteforms. Wasteforms were reacted with carbon dioxide for a prolonged period and then subjected to leaching tests. Ions tested were nitrate, strontium, cadmium, cobalt, calcium, and lead. Results indicate that carbonation causes both physical and chemical changes to the concrete. The leaching rate was higher in the carbonated wasteforms for all the ions except strontium. Thus, effects of carbonation can vary depending on the chemical species and other physical and chemical effects.
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