Abstract: There is provided an energy recovery device for recovering energy from exhaust air which flows through a discharge line. The energy recovery device includes a heat exchanger device having at least a first heat exchanger unit and a heat pump, wherein the heat pump is connected at the high-temperature side thereof to the first heat exchanger unit and is arranged at the low-temperature side thereof in the exhaust air flow in the exhaust air flow direction downstream of the first heat exchanger unit or is connected at the low-temperature side thereof to a second heat exchanger unit which is connected downstream of the first heat exchanger unit in the exhaust air flow direction.

Abstract: There is provided an energy recovery device for recovering energy from exhaust air which flows through a discharge line. The energy recovery device includes a heat exchanger device having at least a first heat exchanger unit and a heat pump, wherein the heat pump is connected at the high-temperature side thereof to the first heat exchanger unit and is arranged at the low-temperature side thereof in the exhaust air flow in the exhaust air flow direction downstream of the first heat exchanger unit or is connected at the low-temperature side thereof to a second heat exchanger unit which is connected downstream of the first heat exchanger unit in the exhaust air flow direction.

Abstract: The invention relates to a process for treating industrial wastewaters, preferably wastewaters from the metal-processing industry, preferably suitable for treating the wastewater in such a manner that it can be recycled back to the production. In the process the wastewater passes through a sequence of treatment steps consisting of a chemical/physical flocculation/precipitation, a filter system, a biological wastewater purification stage and also a nanofiltration unit.

Abstract: The invention relates to a process for the biological treatment of waste water in fixed-bed reactors. The process includes the steps of dividing the waste water (2) into two part streams (10, 11). In one part stream, the pollutants in the waste water are aerobically treated while in the other part stream the pollutants are anaerobically treated.

Abstract: The invention relates to a process for treating industrial wastewaters, preferably wastewaters from the metal-processing industry, preferably suitable for treating the wastewater in such a manner that it can be recycled back to the production. In the process the wastewater passes through a sequence of treatment steps consisting of a chemical/physical flocculation/precipitation, a filter system, a biological wastewater purification stage and also a nanofiltration unit.

Abstract: Annular metallic blanks which consist of packages of interconnected laminae or of sheet metal strips which are coiled edgewise and whose strata are riveted or otherwise secured to each other are converted into stators for electrical machines by cold forming between upper and lower dies and outer and inner calibrating members so that the inner diameter of each blank is increased during cold forming, that the peripheral surface of the stator has two cylindrical portions flanking a convex median portion, and that the outermost portions of the end surfaces of the stator are formed with annular recesses. Prior to cold forming, each blank is subjected to a preliminary shaping treatment including chamfering the axial ends of its internal and peripheral surfaces.