Co-disposal pollution control method

Abstract

Process for disposal of fossil fuel ash by addition thereto of sodium salts, preferably sodium sulfur oxide salt Na.sub.2 SO.sub.x where x is 3 and/or 4, in an amount ranging from 5-85 weight percent (dry basis) and adjusting the water percentage to within the range of 6-35%, preferably 15-28%. The coefficient of permeability of the ash and sodium salt is reduced from 10.sup.2 cm/sec to the "impermeable" standard of 10.sup.-6 and below. The preferred mixes also call for a smectite clay additive present in the range of from 0.1% to 5%. A flocculant in amounts of 0.01% to 1% can be substituted for about 3-5% of the water content. A principal source of the Na.sub.2 SO.sub.x is sodium FGD waste, preferably from the use of Nahcolite (a natural mineral form of sodium bicarbonate) as an SO.sub.x sorbent in the Nahcolite FGD process. The resulting co-disposal process simultaneously renders the highly soluble Na.sub.2 SO.sub.x (10.sup.2 g/L) and ash impermeable, and suitable for geomorphologically stable landfill disposal by known techniques to heights in excess of 200'.

Dependencies are inferred from the claim text.