Compost by three-stage fermentation - of household refuse

摘要

Conversion of household refuse into compost by a controlled, 3-stage fermentation in which (i), the components are made reactive by a quick, aerobic digestion lasting 24-36 hr. inw hich the refuse is agitated in a current of air at 15-18 degrees C, humidity 40% and pH 4.5-5 (phosphoric acid) which deodorizes the material and initiates swelling of the cellulose; (ii) progressive transition of the alcoholic fermentation of stage (i) to an anaerobic fermentation producing glycerol and organic acids, the stage lasting about 3 days and controlled by raising the humidity, pH adjustment to 7.5-8, raising temp. to 30 (is not >32-35 degrees C) and adding any Na2CO3, NaCl, salts of Al or Fe required for fermentation, reducing the air flow progressively; (iii) maintaining anaerobic conditions of end of stage (ii), pH to 8, humidity to 80% finally dropping to 40-50% in second half of stage.