John D. Hatfield

Melamine: A Regenerative S02 Absorbent

A new regenerative SO2 abatement process using melamine has been developed. In this process a gas stream containing SO2 is contacted with an aqueous slurry of melamine to produce solid melamine sulfite. The solids are separated and thermally decomposed at 100°–200°C. Statistically designed laboratory scrubbing tests using simulated stack gas were performed at 50°C to determine the relative effects of slurry concentration, SO2 concentration, CO2, O2, NO, fly ash, antioxidant, and prescrubber on the melamine scrubbing process. Average SO2 removal for these tests with 2000 and 4000 ppm SO2 was 95.5%, and each mole of melamine absorbed 0.5 mole of SO2. Carbon dioxide (12%) and NO (600 ppm) did not reduce the scrubbing efficiency or capacity of the melamine, and the addition of an antioxidant (0 .1% paraphenylenediamine) effectively minimized oxidation. The melamine scrubbing process looks promising and offers the advantages of high SO2 removal and low energy requirement regeneration.

Melamine a regenerative sulfur di oxide absorbent

A new regenerative SO2 abatement process using melamine has been developed. In this process a gas stream containing SO2 is contacted with an aqueous slurry of melamine to produce solid melamine sulfite. The solids are separated and thermally decomposed at 100°–200°C. Statistically designed laboratory scrubbing tests using simulated stack gas were performed at 50°C to determine the relative effects of slurry concentration, SO2 concentration, CO2, O2, NO, fly ash, antioxidant, and prescrubber on the melamine scrubbing process. Average SO2 removal for these tests with 2000 and 4000 ppm SO2 was 95.5%, and each mole of melamine absorbed 0.5 mole of SO2. Carbon dioxide (12%) and NO (600 ppm) did not reduce the scrubbing efficiency or capacity of the melamine, and the addition of an antioxidant (0 .1% paraphenylenediamine) effectively minimized oxidation. The melamine scrubbing process looks promising and offers the advantages of high SO2 removal and low energy requirement regeneration.