METHOD OF PRODUCING HUMATE-CONTAINING COMPOUNDS Russian patent published in 1998 - IPC

FIELD: organic fertilizers. SUBSTANCE: preliminarily disintegrated raw material is treated by aqueous solution of mixtures of potassium or sodium hydroxide and potassium or sodium carbonate. Hydroxide concentration is maintained at the level from 0.5 to 4.0 wt % and that of carbonate 3.0 to 8.0 wt %. Peat or coal residue is filtered away and filtrate is treated by phosphoric acid to pH 2.0-4.0. Humic acids are then precipitated. Resultant sludge is centrifuged and thickened product is treated by potassium hydroxide to pH 7.0-8.0. Centrifugate is supplemented by potassium or sodium hydroxide and carbonate and thus obtained solution is used to treat new portion of raw material. Product can be used as fertilizer or plant-growth stimulant. EFFECT: reduced decomposition of raw material and increased concentration of product. 2 cl