Abstract: Condensed moisture in devices and/or pipe conduits for anti-corrosion applications in chemical engineering is measured at least one point in the devices and/or pipe conduits by measuring an electrochemical potential difference across two different elements, such as iron and copper, which are arranged one beside the other spaced from 0.001 to 1 mm from each other by an electrically insulating material so as to be electrically insulated from each other. An apparatus for making these measurements is also described.

Abstract: A particulate filter includes a housing having opposite ends, a pair of support walls adjacent respective opposite ends of the housing and defining therein an interior, and a pair of pure gas chambers defined at respective opposite ends of the housing at sides of the respective support walls outwardly of the interior. A plurality of elongated filter bodies are supported by the support walls to extend therebetween within the housing with longitudinal axes of the filter bodies extending parallel. The filter bodies define outwardly thereof within the housing a raw gas chamber in the form of a plurality of elongated raw gas compartments. Hollow interiors of the filter bodies define respective elongated pure gas channels. Each pure gas channel opens into at least one of the pure gas chambers.

Abstract: A device for converting solar energy into process heat has a number of heat xchanging pipes traversing a heat exchanger chamber. A first partial stream of gas to be heated is delivered to inlets of the pipes via an upper distribution chamber, and the first partial stream of gas is subsequently collected from outlets of the pipes in a lower distribution chamber. An inlet aperture of the heat exchanger chamber receives sunlight radiation and a second partial stream of gas to be heated, the second partial stream of gas flowing around the heat exchanger pipes. The heat exchanging pipes absorb the solar radiation and heat both the first partial stream flowing through the pipes and the second partial stream flowing around the pipes. The heated second partial stream is collected by a heated gas outlet conduit connected to the heat exchanger chamber.

Abstract: A catalyst for use with ammonia for the selective reduction of nitrogen oxides in waste gases. The catalyst comprises a mixture of substances which has high activity and selectivity with regard to nitrogen oxide conversion and high sorption capabilities with regard to ammonia, but low oxidation capabilities with regard to sulfur dioxide, ammonia, or similar substances. The invention also provides a process for the manufacture and use of such catalysts.

Abstract: In a process for the reactivation of a catalyst, which is used for the removal of NO.sub.x, oxides of nitrogen, from exhaust gases, the catalyst should be capable of easy reactivation. For this purpose, when the catalyst starts to lose its activity, it is exposed in a reducing atmosphere to a carbon monoxide current. In an apparatus for the execution of the process, the catalyst is placed in two separate chambers. The carbon monoxide stream is directed alternately to both chambers.

Abstract: A heat exchanger and especially a blast preheater (or cowper) for blast furnaces with refractory lining, insulating layer and steel jacket is described, the insulating layer of which is designed so that a steel jacket temperature of from 20.degree. to 60.degree. C. can be set and that said steel jacket is made of chromeless structural steel having a molybdenum content in the range from 0.01 to 2% by weight. The blast preheater (or cowper) has a prolonged service life and a low tendency to nitrate tension crack corrosion of the jacket sheet, for which reason it is very suitable for use in a process for the temperature control of gas and blast for the blast furnace. The process is suitable for blast preheaters (or cowpers) with external or internal combustion chamber or checker chamber and downstream collector ducts.

Abstract: Equipment for testing materials for the effects of stress corrosion cracking, which includes more than two tensioning units, each consisting of a base plate, two guide bars, an upper and a lower cross-beam, a locking system for the guide of the lower cross-beam and a connecting flange between the cross-beam and a threaded bar for causing elongation of a test sample. The power drive supply block drives the threaded bar. A motor power unit is included in the power drive supply block and vertically-slippable gearing is inserted between the motor gearing and the block. The motor power unit consists of two stepping motors driving sun gears. The sun gears drive planetary gears which, by means of an arm, drive the drive shaft operatively associated with the threaded bar. In particular, the invention relates to equipment with six tensioning units comprising an automatic limit switch-off means and a lift system in the power drive supply block for separating the drive gears from the rest of the system.