Abstract: An insulating feedthrough for an electrostatic precipitator has a cylindrical insulator passing through a hole in the wall of the precipitator and having an annular flange which is sealingly pressed against the inner surface of that wall by a clamping arrangement including a spring. A tubular bushing extends through the insulator and has a flange bearing upon the inner end of the latter which is connected by a clamping arrangement to a flange on the support for the electrodes via another spring. A rod for transmitting rapping blows passes through the bushing to impact against the electrode support.

Abstract: Disclosed is an apparatus and process for an energy producing plant utilizing a circulating fluidized bed system having an integral fluidized bed heat exchanger, the fluidized bed reactor and integral heat exchanger having a common wall with at least one perforation for fluid communication therebetween. In the system, solids are separated from the reactor flue gas, and in dependence upon a process variable, are directed in varying amounts either directly back into the reactor or into the integral heat exchanger, the latter being operated as a classical and/or bubbling bed at a higher pressure than the reactor. A heat exchange medium passes through tube bundles immersed in the exchanger fluid bed and the bed solids and fluidizing gas in the heat exchanger are passed through the perforation to control the reactor operation.

Abstract: A trackless, center-pivot underground vehicle is described, which has a tractor section, which is driven by an electric motor, which is powered via a sliding contact line, a current collector device, which is movable along the contact line line, and a supply cable, which is electrically and mechanically connected to the current collector device and adapted to be unwound from a reel against a restoring force. An improved mobility of the vehicle and a large width range throughout the range of travel are ensured by the combination of the following features:a. the supply cable is connected to the current collector device by a slip ring member, which is rotatable about a vertical axle;b. a helically winding cable reel is mounted on the tractor section and rotatable about a vertical axle, which is provided with a slip ring member;c. a guide arm is coaxially arranged with respect to the cable reel and adapted to be pivotally movable by hydraulic means; andd.

Abstract: In a process of removing pollutants consisting substantially of sulfur oxides from exhaust gases at temperatures below 150.degree. C. by means of a sorbent which contains calcium carbonate, calcium oxide and/or calcium hydroxide and which is included in a circulating fluidized bed system consisting of a fluidized bed reactor, a separator and a return line, a complete utilization of the sorbent is achieved in that a partial stream of laden sorbent is withdrawn from the circulating fluidized bed and is subjected at a temperature of 600.degree. to 1200.degree. C. to an oxidizing treatment, a major part of the sorbent that has been subjected to an oxidizing treatment is recycled to the circulating fluidized bed, and a partial stream which contains the sorbent mainly in the form of calcium sulfate is removed from the process. Fresh sorbent is supplied to the circulating fluidized bed and/or to the stage for the oxidizing treatment at the rate at which said partial stream is removed from the process.

Abstract: In a method of processing contaminated sodium oxalate which becomes available in a separating stage succeeding the digestion of bauxite in accordance with the Bayer process, chemicals used in the digesting process are recovered in that moist sodium oxalate which has been separated is dried with the hot exhaust gases from a rotary kiln jointly with aluminum hydroxide or aluminum oxide hydrate and/or reactive alumina at a mole ratio of aluminum to sodium of at least 0.8 and the dried product is decomposed in said rotary kiln at a temperature of 780.degree. to 1000.degree. C. to form sodium aluminate. Suitably drying is effected by spray drying in direct contact with the exhaust gases of the rotary kiln and decomposition is effected at a temperature in the range from 850.degree. to 950.degree. C. and with an Al:Na ratio not in excess of 1.2.

Abstract: Oil-containing solids are dried and heated by contacting them in a drying zone with superheated steam admitted to the zone at a temperature in excess of 200.degree. C. The heated solids may be distilled to remove hydrocarbons therefrom and the resulting proceduce and/or combustion products of the distillation or other combustion products are used to heat a mixed vapor remainder, after separation of said carbon from the vapors formed during the drying, to the temperature of 1200.degree. C. for recirculation to the drying zone.

Abstract: In a method for processing contaminated sodium oxalate which becomes available in a separating stage succeeding the digestion of bauxite in accordance with the Bayer process, chemicals used in the digesting process are recovered in that the moist sodium oxalate which has been separated is dried with the hot exhaust gases from a fluidized bed, particularly a circulating fluidized bed, jointly with aluminum hydroxide or aluminum oxide hydrate and/or reactive alumina at a mole ratio of aluminum to sodium of at least 0.8 and the dried product is decomposed in said fluidized bed at a temperature of 780.degree. to 1000.degree. C. to form sodium aluminate. Suitably drying is effected by spray drying in direct contact with the exhaust gases of the fluidized bed and decomposition is effected at a temperature in the range from 850.degree. to 950.degree. C. and with an Al:Na mole ratio not in excess of 1.2.

Abstract: A mixture will involve a risk of explosion if a concentration limit is exceeded. For this reason only part of the liquid is admixed to the gas in a first mixing zone so that the concentration limit above which there is a risk of explosion will not be exceeded. In a second mixing zone, the remaining quantity of liquid is added to the mixture withdrawn from the first mixing zone and the explosive concentration is exceeded. That mixture, in which the gas and liquid are distributed as homogeneously as possible, is reacted in a reaction zone. The reaction zone directly succeeds the second mixing zone.

Abstract: The feed gas is partially burnt with oxygen-containing gas in a thermal Claus process plant, in which temperatures in the range of 850.degree. to 1350.degree. C. is maintained. Product gas which has been produced is passed through a catalytic Claus process plant (Claus catalysis plant), from which sulfur is withdrawn. The exhaust gas from the Claus catalysis plant is supplied to a desulfurizing plant. The sulfur compounds in the exhaust gas of the desulfurizing plant are converted to SO.sub.2 in a thermal aftertreating unit. When the rate of the H.sub.2 S-containing feed gas is below a limit, which is between 20 to 35% of the total rate of feed gas permissible for the thermal Claus process plant, then recycled exhaust gas from the desulfurizing plant (recycle gas) is admixed to the feed gas at such a rate that the rate of the mixed feed and recycle gases exceeds that limit. The recycle gas is suitably heated to 200.degree. to 400.degree. C. before it is mixed with the feed gas.

Abstract: A process for the manufacture of thin activated electrodes including a base metal, which can be iron, cobalt or nickel, with a good adhering active surface layer. Both the base metal and the surface layer are galvanically sequentially deposited as separate layers on a removable electrically-conductive carrier. The surface layer is deposited as an activatable alloy including the base metal and a leachable metal, particularly zinc. The galvanizing deposited layers are subsequently separated as a unit from the carrier. The alloy is activated by leaching the leachable metal therefrom before, during or after separation of the carrier. Two activatable layers of alloy can be deposited on the carrier with a layer of the base metal deposited between the alloy layers.

Abstract: A reactor is provided for producing methanol by the reaction of synthesis gases containing carbon oxides and hydrogen in contact with a copper containing catalyst positioned in the reactor in catalyst tubes surrounded by boiling water under pressure. The catalyst tubes are made from a metallic material which is catalytically inactive with respect to the methanol synthesis gas and have approximately the same coefficient of thermal expansion as the shell of the reactor. The catalyst tubes are made of a steel composed of mixed austeniticferritic structure and containing 10-30% by weight chromium.

Abstract: The present invention provides a treatment agent for cast iron melts based upon ferrosilicon magnesium with a silicon content of from 40 to 80% by weight and a magnesium content of from 0.5 to 15% by weight, said agent being in the form of granules with a specific surface area of from 0.2 to 0.8 m.sup.2 /g. according to BET.The present invention also provides a process for the production of this treatment agent, wherein a jet of molten ferrosilicon magnesium alloy is directed on to a bounce plate made of fire-resistant material and the melt droplets which bounce back from bounce plate are allowed to solidify in a liquid-filled collection receiver.

Abstract: For a dust-collecting plant, in which a plurality of gas streams are sucked from spaced apart dust sources and are delivered in a manifold to a dust-collecting unit and the gas is delivered by a controllable exhaust fan to an exhaust gas chimney, a method is provided wherein the automatic control and the operation of the plant are improved whereas the power requirement is minimized. A feedback control system having an individually adjustable desired value r.sub.i is associated with each gas source. An overriding feedback control system is provided for controlling the exhaust fan. The pressure drop R to be maintained by the exhaust fan is changed in dependence on the position of the final control elements associated with the several dust sources.

Abstract: Sponge iron produced by direct reduction is melted in an electric arc furnace, in which a pool of liquid metal is maintained. To ensure that liquid carbon-containing iron for forming the pool is available in adequate quantities and that the process can be carried out with the highest possible economy, the sponge iron is reacted in an electric arc furnace on a bath of liquid carbon-containing iron (hot metal), which has been produced from sponge iron or from partly reduced ore in an electric reducing furnace, and in dependence on the electric load changes which are due to the operation of the electric arc furnace the operation of the electric reducing furnace is so controlled that a virtually constant load on the electric power supply system is maintained.

Abstract: Heavy hydrocarbon oil to be processed is subjected to a treatment at elevated temperature and superatmospheric pressure in the presence of dispersed solids and molecular hydrogen and recycled hydrogen donor oil. By this treatment, a certain part of the asphaltenes absorbed on the solids may be coked. The product of that donor solvent hydrovisbreaking (DSV) is distilled. The distillate or distillates is or are catalytically hydrogenated. The visbreaking residue is used for the production of hydrogen. The hydrogenated products are separated in hydrocarbon fractions and are then processed further to fuels and/or petrochemical products and a part of the hydrogenated products is recycled as inherent donor solvent.

Abstract: An improved process for the treatment of aqueous effluents containing strong anions such as sulphate, nitrate, chlorides and fluorides wherein the aqueous effluent is subjected to a biological purification process is described. According to the process, aqueous effluent such as those obtained by condensation of gases present in a coal gasification plant and containing these anions and others in a combined concentration of at least 2 mval/l and organic contaminants in a concentration of at least 1000 mg/l are subjected to the biological purification followed by separation of water from solids of the effluent. Thereafter, the water is subjected to anion exchange in an anion exchanger against hydrogen carbonate ions and at least part of the so-treated water is recycled to the aqueous effluent so as to be present therewith during the biological purification. By such a process the biological purification can be conducted at an optimum pH such as a pH in the range of 6 to 8. CO.sub.3 /HCO.sub.

Abstract: A process of leaching ores, ore concentrates, intermediate metallurgical products and the like, which contain acid-soluble constituents, by a treatment in an acid aqueous solution under pressure in a tubular reactor. The slurry contains suitably 300 to 1100 g starting material per liter of water and a velocity of flow of 0.5 to 4.0 m/sec. is suitably maintained throughout the flow path in the tubular reactor of the slurry and of the leached suspension.

Abstract: Gold and/or silver is leached from comminuted ore with an alkaline cyanide lixiviant at a superatmospheric pressure of at least 25 bar and with high purity oxygen (at least 90% pure) to reduce the residence time at high yield.

Abstract: Cement clinker is produced in that raw cement powder is preheated in a suspension-type heat exchanger and is de-acidified in a fluidized bed and clinkered in a rotary kiln, and the clinker is subsequently cooled. A de-acidification of at least 95% is effected at a temperature above 850.degree. C. in a circulation system comprising a fluidized bed reactor, a cyclone separator and a recycling duct. The carbonaceous fuel required for the calcining and clinkering processes is fed in an amount of at least 65% (related to the total heat requirement) to the de-acidifying fluidized bed reactor and in an amount of at least 10% (related to the total heat requirement) to the clinkering rotary kiln.The fuel supplied to the de-acidifying fluidizing bed reactor is burnt near stoichiometrically in two stages with fluidizing gas and secondary gas. The ratios of the rates and volumes of fluidizing gas to secondary gas are so selected that a mean suspension density of 100 to 300 kg/m.sup.

Abstract: A method of optimizing the collection efficiency of a dry-process electrostatic precipitator which is preceded by an evaporative cooler, wherein liquid is sprayed into the evaporative cooler at a rate which is controllable to maintain a desired temperature includes the steps of intermittently measuring the dew points of acid separately and setting the desired temperature T.sub.c in dependence on the measured dew point of acid and a preselected margin of safety .DELTA.T, in accordance with T.sub.c =T.sub.s +.DELTA.T, determining a desired input current I.sub.c for the electrostatic precipitator at T.sub.c and storing I.sub.c, and continuously calculating the deviations of the actual input current I of the precipitator from the desired input current I.sub.c and initiating the measurement of the dew point T.sub.s of acid in response to a predetermined deviation to update the desired temperature T.sub.c.