FOERFARANDE OCH APPARATUR FOER BEHANDLING AV HUSHAOLLSAVFALL

A method for processing household wastes involves electromagnetic separation of household wastes in a magnetic field with an intensity of 20 to 40 ka/m, and then composting them in a biological and thermal treatment drum under aeration and stirring, which is carried out alternately at maximum and minimum speed of rotation of the biological and thermal treatment drum. The speed is lowered to minimum value when the temperature of the household wastes in 25-35 DEG c and 52-55 DEG c, respectively, and the speed is raised to a maximum value when temperature in household wastes is 45-50 DEG c and 60-70 DEG c, respectively. Composted wastes are separated into compost and non-decomposable wastes. An apparatus for carrying out the method has, mounted in series, an electromagnetic separator (3), a driven cylindrical biological and thermal treatment drum (5) having a cover (7) which is stationary with respect to the drum, an annular collector (14) mounted on the biological and thermal treatment drum (5) on the side of the cover (7) for trapping spillage of wastes, a discharging device (24) and a device for separating composted wastes into compost and non-decomposable wastes. A cylindrical nozzle (11) and a labyrinth seal (12 - Fig. 2 - not shown) are provided within the drum (5). Helically extending fins (17,18) are provided on the inner surface of the drum (5) for moving and stirring household wastes, which have trapezoidal slots in a zone spaced from the ends of the drum (5). The length of this zone is 0.85-0.95 of the length of the drum (5). Plates (19) are provided between the fins (18) in this zone, which extend at an angle with respect to the generant of the drum (5) in a direction opposite to the direction of these fins (18) with respect to the generant.