The report gives results of a study to extend potential applications of MgO flue gas desulfurization processes by allowing the sulfur to be recovered as elemental sulfur as well as sulfuric acid. The study considered the feasibility of combining the exothermic SO2 reduction reaction with the endothermic MgSO3 calcination. Preliminary consideration of the reductants carbon monoxide, hydrogen, methane, and hydrogen sulfide showed that the reaction with SO2 can supply part, or in some cases all, of the heat of decomposition of MgSO3. Considered in detail were: (1) low-temperature catalytic decomposition using a commercially available low-Btu synthetic-gas reductant mixture; and (2) high-temperature noncatalytic decomposition using a medium-Btu reducing gas from an oxygen-blown gasifier. Complete heat and material balances for conceptual process designs for the above cases were developed to identify problems. Recommendations for work required to continue process development are given. Problems identified include catalyst physical stability, catalyst/MgO separation, dust carry-over, and noncatalytic reduction kinetics.

"EPA 600-7-76-030." "October 1976." Cover title. Contract no. 68-02-1319, task 31, program element no. EHB528. Includes bibliographical references (page 211).