Patent ID: 7914731

Claim:
An apparatus for sintering metal-containing materials, comprising a sintering machine including a charging device for charging a sinter mix containing solid fuel, a movable sintering belt having a surface with an entrance area to which the charging device charges the sinter mix and having a discharge area where a sinter leaves the belt; an igniting device operable for igniting the sinter mix on the surface; suction boxes positioned and operable for passing oxygen-containing process gas through the sinter mix on the belt at three successive portions along the sintering belt, wherein a first portion of the belt adjoins the charging device and a third portion of the belt is bordered by the discharge area of the sintering belt; a first collecting line connected to and operable for unifying and passing on sintering waste gas occurring in the suction boxes of the third portion, and second connecting lines connected between and operable for feeding the sintering waste gases from the suction boxes of the third portion into the first collecting line; a discharge line connected to and operable for unifying and passing on sintering waste gas occurring in the suction boxes of the second portion, and third connecting lines connected to and operable for feeding the sintering waste gases from the suction boxes of a second portion of the belt into the discharge line; a device for producing a mixed gas from sintering waste gas from the first portion of the sintering belt and the sintering waste gas from the third portion of the sintering belt, and fourth connecting lines for feeding the sintering waste gases from the suction boxes of the first portion into the device for producing a mixed gas; the device for producing a mixed gas comprises the first collecting line for the sintering waste gases from the third portion of the sintering belt; a device operable for transporting and distributing the mixed gas as process gas to be used for the second portion to the sinter mix in the second portion of the sintering belt; a waste gas line connected to and operable for discharging from the discharge line the sintering waste gas from the second portion of the sintering belt and for discharging that gas from a sintering machine; a sinter cooler arranged downstream of the discharge area of the sintering belt; a mixing region of the first collecting line; the fourth connecting lines for feeding in the sintering waste gas from the suction boxes of the first portion of the sintering belt open out into the mixing region, wherein the distance of the third portion from the mixing region is greater than the distance of the first portion from the mixing region; and the connecting lines extending from at least some of the suction boxes each have two openings, wherein one of the openings leads into the collecting line of the device for producing a mixed gas and the other of the openings leads into the discharge line.