Abstract: Referring to process and equipment for the indirect drying of sludge, especially for the drying of wastewater sludge, which may undergo previous mechanical dehydration and/or preheating, it is intended to provide a method that permits utilizing low-value energy for drying purposes while avoiding environmental nuisance. With reference to the process, the problem is solved by drying the sludge under vacuum which is produced by withdrawing the water vapor by means of an injection condenser, the equipment provided for solving the problem comprising a barometric condensor associated with a mechanical sludge dehydrator and at least one sludge drier for indirect drying with an hermetically closed sludge space, the gas dome of the sludge space being connected to the injection condenser through a line for withdrawal of the water vapor.

Abstract: A gas-tight crossflow heat exchanger consisting of a metal casing with two gas inlet nozzles and two gas outlet nozzles, at least one installation cover on the top of the casing, a block consisting of a number of ceramic heat-exchange elements mounted completely accurately in cuboid form with gas ducts arranged in layers one above the other and running at right angles to each other, four side surfaces having gas-duct openings, and the bottom and top surfaces being free of openings, the heat exchanger further consisting of thermal insulation between the metal casing and the block of ceramic heat-exchange elements.

Abstract: In reheating and conveying a granular heat carrier, such as sand, which is transportable by a gas and is used for desorption by heating a charged lumpy adsorber, such as activated carbon pellets, the sand is passed upwardly in a cylindrically shaped pipe element in the form of a fluidized bed. The sand is heated during its upward passage through the fluidized bed. Air introduced into the lower part of the pipe element is used as the fluidizing medium and also as combustion air. Further, fuel is supplied into the lower part of the pipe element. From the upper end of the pipe element, the heated sand flows downwardly by gravity to a sand separator, where it is separated from flue gas, into a desorber where it is contacted by the absorbent and then into a device for separating the sand and the adsorbent so that the sand can be returned into the lower end of the pipe element.

Abstract: This invention relates to a process for the desorption of spent solid adsorbent through heating the latter to desorption temperature by means of a hot granular heat carrier medium; particularly of activated coal or activated coke used for flue gas purification by adsorption in power plants, for example.

Abstract: Process and apparatus for incinerating contaminated salt-bearing solutions in a fluidized bed to which streams of solution, of fuel required for incineration and of combustion air are injected and the quantities of these streams and the quantity of the fluidized bed material are adjusted to safeguard incomplete combustion in the fluidized bed, to maintain the temperature of the bed below the fusion temperature of the salt and to achieve a post-combustion temperature of 800.degree. C and more of the gas emanating from the fluidized bed and reaching the free space above the bed, i.e. the afterburner.