Abstract: A process and an apparatus for melting solidified gel masses, in particular of photographic emulsions, which are introduced as solid pieces of any size or shape into a melting container having a perforated bottom and equipped with a tempering device, the gel mass when melted flowing through the openings in the bottom into a receiver underneath it, and being arranged and designed to prevent excessive exposure of the gel mass to heat. This is achieved by melting the layer of gel mass immediately above the bottom of the melting container with microwaves while the layers of gel mass situated above the aforesaid layer remain substantially uninfluenced by the radiation of microwaves.

Abstract: The invention relates to a process for the automatic preparation of solutions from environmentally noxious substances in solvents whereby the noxious substance is brought on a receiver and by means of an airtight adapter and a feed connection into a hermetical sealed, storage bin, an exact quantity of the substance is dosed into a measuring and mixing vessel by means of a dosing screw after the solvent is dosed into this vessel, the substance is mixed and dissolved maintained at a certain temperature filtered and delivered to a storage vessel in an automatic sequence.

Abstract: The invention relates to a process and an apparatus for continuously filtering liquids whereby two candle filters are arranged closely adjacent to one another and are connected by a first three-way cock at the liquid inlet ends, a second three-way cock at the liquid outlet ends of the candle filters and a bypass cock for a partial stream and enabling the candle filters to be emptied in such a manner that the candle filters are filled and vented before they are put into operation and one of the two candle filters always is ready for operation with degassed and filtered liquid if one of the candle filters is to be cleaned.

Abstract: A constant stream of liquid per unit of time is dispensed under normal pressure from a storage vessel by means of a metering element which is rigidly connected to a float and whose diameter is smaller than the internal diameter of the outflow pipe or tube, the vertical position of the metering element changing with the liquid level in the storage vessel.