METHOD OF PRODUCING LIQUID SULFUR-FREE ORGANIC FUEL Russian patent published in 1998 - IPC

FIELD: waste disposal and fuel production. SUBSTANCE: invention relates to producing fuel from waste formed when biologically treating industrial and household sewage. Suspension of excess activated sludge after biological treatment is compacted to concentration 25-90 g/l and subjected to alkali hydrolysis by treatment with sodium hydroxide or its mixture with sodium carbonate in amount 10-50 kg/t based on completely dry matter. Alkali hydrolyzate obtained is separated from undissolved part of sediment and evaporated to concentration 75-80 wt %. Resulting sulfur-free fuel with high calorific value, when burned produces minimum amount of dioxins (1 pcg per 1 cu. m of gas) and meets most strict European rates (not higher than 100 pcg per 1 cu.m of gas). Excess activated sludge is completely utilized. EFFECT: improved quality of fuel and environmental conditions. 1 dwg