METHOD OF PREPARING SLUDGE-MASH COMPOST Russian patent published in 2009 - IPC C05F7/00 

FIELD: chemistry.

SUBSTANCE: invention can be used for bio-conversion of sewage sludge with low content of heavy metals combined with brewing wastes - brewery mash and diatomaceous earth into quality compost with low cost price. The method involves mixing fresh dehydrated sewage sludge and residue from warehouses with shelf life of less than three years with an organic component in form of brewery mash, with a cellulose-containing component in form of sawdust and/or peat with volume ratio of components 0.5-0.6:0.3-0.4:0.1-0.2, respectively, addition of a bioactivator in amount of not less than 15% of the volume of the compost mixture, and aerobic composting. Aerobic composting is done with simultaneous drying of the mixture through forced aeration with inlet of 0.7-0.8 m³/h of air per 1 m³ of the mixture for 15-20 days in modes of 30-35 minutes blowing, 30-25 minute pause or 15-17 minutes blowing, 15-13 minute pause twice in an hour with subsequent maturation of the compost in 2-2.5 months with inlet of 0.1-0.3 m³/h of air per 1 m³ of the mixture in the given modes in the first 20-25 days. A mineral component is also added, which is in form of spent diatomaceous earth in amount of not less than 2% of the mass of the mixture.

EFFECT: faster maturation of the compost due to faster rate of biothermal sanation and fermentation of wastes, done while drying the mixture, higher quality of the compost due to improved sanitary- bacteriological index and ameliorative properties of the compost while reducing cost price of the end product.

2 cl, 3 tbl, 10 ex