FIELD: public services. SUBSTANCE: method involves a stage of biological filtration followed by aeration and settling. The initial biological treatment is carried out by biological filtration through a multilayer filtering charge with immobilized microorganisms, followed by treatment in the underlying zones. Simultaneously the sewage is nitrified-denitrified and settled after which the biologically-treated sewage is finally treated physicochemically by filtration through a multilayer filter containing a layer of peat in some cases modified with a polymeric cation, a layer of zeolite in some cases modified with a polymeric cation, a layer of peat-zeolite mixture and a layer of zeolite. Any materials of the filtering layers can be modified with polymeric cation. The invention also comprises a device for the realization of the claimed biochemical treatment method comprising a casing with a biofilter, an aeration zone underneath, separated by a vertical partition from the settling zone. The biofilter is charged with at least two layers of packings with a highly-developed surface and a high porosity increasing from top down along the water flow, the aeration zone has pneumatic aerators and an airlift aerator filled with a packing, the casing also has the denitrification and degassing zones hermetically closed with a cover. EFFECT: highly efficient treatment of sewage in a compact device. 2 cl, 1 dwg 1 tbl
