Abstract: Metallurgical converter gas is scrubbed in a wet-process electrostatic precipitator utilizing a cylindrical housing and axially separated collecting fields which themselves are vertically subdivided.

Abstract: A continuous process of removing silica from spent pulping liquors (black liquors) which have been obtained by the alkaline digestion of annual plants. The spent liquor is preconcentrated and contacted with a CO.sub.2 -containing gas. The CO.sub.2 -containing gas is supplied at a rate of 30 to 40 m.sup.3 s.t.p. per m.sup.3 of spent liquor. The precipitated silica is removed from the treated liquor. The silica-containing precipitate which has been separated is diluted and washed with water and causticized by an addition of lime or milk of lime. Solid and liquid phases are separated from each other and the resulting residue is combusted.

Abstract: In a process of regenerating laden absorbent solutions used to desulfurize gases which contain H.sub.2 S and CO.sub.2 and possibly COS, which solutions contain at least one highly volatile secondary amine in an organic solvent, the laden absorbent solution is flashed and stripped with its own vapor. The overhead vapors from the regenerator, which consists of an indirectly heated plate column, are cooled to approximately ambient temperature. The resulting condensate is separated and fed to the top of the regenerator. The cooled gas is withdrawn. A partial stream of the vapor is withdrawn from the regenerator 1 to 10 plates below the outlet for the overhead vapors and the inlet for the condensate and is cooled to ambient temperature. The resulting condensate is fed to the regenerator 1 to 10 plates above the inlet for the absorbent solution.

Abstract: In an electrolytic cell having a membrane and vertical electrodes composed of a plurality of units,a. the electrode having one polarity is horizontally divided into a plurality of units,b. the electrode having the opposite polarity is vertically divided into a plurality of units, andc. the units of at least one of the two electrodes are adapted to be displaced by spring elements. Spacers are suitably provided between the units of that electrode which is not contacted by the membrane.

Abstract: A process is disclosed for converting a non-distillable residue of a mixed-base or paraffin-base crude hydrocarbon oil to a distillable precursor for motor fuels and/or petrochemical products which comprises donor solvent hydrovisbreaking said residue in a hydrovisbreaking zone in the presence of a circulated hydrogen donor solvent at a temperature in the range of 380.degree. to 480.degree. C.

Abstract: Desulfurized hydrocarbons are reacted with water vapor on catalysts at temperatures of 700.degree. to 1200.degree. C. to form a high-hydrogen product gas, which is separated in a pressure-swing adsorber into purified hydrogen and a separated gas, which contains substantially carbon oxides and methane. The purified hydrogen is supplied to a hydrogenating plant, which is operated at temperatures in the range of 250.degree. to 500.degree. C. and pressures of 200 to 400 bars. High-hydrogen gas from the hydrogenating plant flows in a pipeline through a heater and is then recycled to the hydrogenating plant. The heater consists of a fuelfired reheater, in which the separated gas is used as a fuel. The pipeline in which the high-hydrogen gas is recycled between the hydrogenating plant and the heater consists of an alloy steel, in which the carbon is combined in carbides with at least one of the alloying constituents chromium, molybdenum, tungsten or vanadium.

Abstract: In a process of recovering and cleaning catalysts in the continuous production of fat alcohols by a catalytic hydrogenation of fatty acids or fatty acid derivatives at temperatures of 240.degree. to 330.degree. C. and pressures of 200 to 700 bar in the presence of copper-chromium oxide catalysts, wherein the reaction is carried out in the presence of material which has been already reacted, the resulting dispersion is circulated through the filter which is due for cleaning until the contents of the stirring vessel is free of solids and the filter cake is substantially free of product, the liquid from which solids have been removed is separated into cleaning liquor and recovered product by a simple sedimentation in a liquid-liquid separator or by a distillation, the recovered product is fed to the main product, the catalyst which is moistened with the cleaning liquor and substantially free of product is withdrawn and, if required, is dryed.

Abstract: In gas-forming electrolyzers, particularly membrane electrolyzers having vertically extending plate electrodes, each electrode plate is divided into horizontal strips and the entire active electrode surface is parallel to the counterelectrode and spaced from it as closely as possible. The top portions of each of the horizontal strips into which the electrode is divided define gas escape paths and extend away from the counterelectrode. To improve the degassing of the electrolyte the ratio of the distance G between the counterelectrode or membrane and the gas-defining line S at the lower edge of each electrode strip to the distance E between the counterelectrode or membrane and the breakaway edge K of the angled portion defining the gas escape path corresponds to a degassing capability F which is lower than 0.6.

Abstract: In the operation of the rotary kiln provided at its charging end with a central burner, solid reducing agents having a high content of volatile constituents are used and the charge and the gas atmosphere are conducted in cocurrent streams. To avoid a high heat load per unit of volume in the heating-up zone and yet to increase the heating-up rate, a solid carbonaceous reducing agent having a high content of volatile constituents is charged together with the iron oxide-containing material into the charging end of the rotary kiln, oxygen-containing gases are blown through nozzle blocks into the free gas space and into the charge in the heating-up zone, and oxygen-containing gases are blown through nozzle blocks into the free kiln space in the reducing zone.

Abstract: Devolatilizable fine-grained material which contains hydrocarbons is devolatilized by means of fine-grained solids which have been heated to temperatures of about 500.degree. to 1000.degree. C. The devolatilizable fine-grained material is mixed with the heated solids and is thus heated to temperatures of about 400.degree. to 900.degree. C. The mixture is passed through a dwell zone, and gaseous and vaporous devolatilization products are withdrawn and cooled. The heated solids are fed to the dwell zone as a loosened stream in a trickling and/or agitated state of motion, and the devolatilizable fine-grained material is introduced into said stream in order to be admixed thereto. The heated solids and the devolatilizable fine-grained material can be mixed in a weight ratio of 3:1 to 12:1. The stream of trickling heated soids can be deflected at least in part.

Abstract: In order to reduce the wear and to facilitate the replacement, a nozzle block comprises a mounting plate which is connected to the kiln shell, a nozzle tube which extends in the mounting tube and defines a clearance with the mounting tube and with the kiln lining, an abutment surface provided at the lower end of the nozzle tube and engaged by the orifice plate and which is clear of the body of the nozzle tube, a retaining tube which extends in the nozzle tube and defines a clearance with the nozzle tube and with the orifice plate, a gas feed duct attached to the side of the mounting tube and a cover on the mounting tube.

Abstract: This invention relates to a filter press type electrolyzer for water comprising pressure-resistant decomposing cells, each of which contains an electrolyte chamber, which is divided by a diaphragm into two electrode compartments. The decomposing cells are enclosed on the outside by cell frames, which are electrically insulated from each other by an interposed sealing ring. On the sides, each cell is separated from the adjacent cells by metallic cell-separating partitions. At least three ducts extend through the cells and respectively serve to supply electrolyte and to discharge hydrogen and oxygen. Each duct is composed of sections. The sections of the ducts consist of sleeves, which are resistant to the operating conditions and insulated from each other and extend through openings in the cell-separating partitions. These openings are lined with metal rings.

Abstract: In a process of simultaneously producing fuel gas and process heat from carbonaceous materials wherein the carbonaceous materials are gasified in a first fluidized bed stage and the combustible constituents left after the gasification are subsequently burnt in a second fluidized bed stage the throughput rate and the flexibility are increased in that the gasification is carried out at a pressure of up to 5 bars and a temperature of 800.degree. to 1100.degree. C. by a treatment with oxygen-containing gases in the presence of steam in a circulating fluidized bed and 40 to 80% of the carbon contained in the starting material are thus reacted. Sulfur compounds are removed from the resulting gas in a fluidized state at a temperature in the range from 800.degree. to 1000.degree. C. and the gas is then cooled and subjected to dust collection.

Abstract: Fine-grained material which contains iron oxide is prereduced in a fluidized bed and is subsequently completely reduced in a rotary kiln. In order to avoid agglomeration and incrustation in the rotary kiln, the prereduction is carried out to effect a metallization of 50 to 80%.

Abstract: Gases are blown into the kiln through its shell by means of shell pipes or nozzle blocks. The rates at which gases actually enter the kiln are ascertained in that the pressure in each supply duct is pneumatically tapped at a constriction and is applied to a transducer, which is secured to the kiln. A differential pressure is ascertained by the transducer and converted to an electric signal, which is delivered to a control station via slip rings, which are secured to the kiln, and stationary taps.

Abstract: A method of recovering uranium dioxide from a sodium uranyl carbonate solution obtained by the alkaline carbonate leaching of uranium ore in which a solution is reacted at a temperature above 130.degree. C. and at superatmospheric pressure with particular metallic iron. The precipitated UO.sub.2 is recovered from the solution.

Abstract: Devolatizable fine-grained material which contains hydrocarbons is devolatilized by means of fine-grained solids which have been heated to temperatures of about 500.degree. to 1000.degree. C. The devolatilizable fine-grained material is mixed with the heated solids and is thus heated to temperatures of about 400.degree. to 900.degree. C. The mixture is passed through a dwell zone, and gaseous and vaporous devolatilization products are withdrawn and cooled. The heated solids are fed to the dwell zone as a loosened stream in a trickling and/or agitated state of motion, and the devolatilizable fine-grained material is introduced into said stream in order to be admixed thereto. The heated solids and the devolatilizable fine-grained material can be mixed in a weight ratio of 3:1 to 12:1. The stream of trickling heated solids can be deflected at least in part.

Abstract: In order to avoid incrustation and an excessively strong thermal attack on the afterburning chamber, the exhaust gases which contain gaseous and solid constituents which are combustible are afterburned in a plurality of stages, which are connected in series. The rate at which oxygen is supplied to each stage is so controlled that part of the combustible constituents is afterburned in each stage. The gas which is about to enter each succeeding stage is cooled by injected water.

Abstract: The gases are injected through double-tube nozzles which extend through the wall of the reactor into the molten bath. A cooling protective fluid is injected through one tube of each double-tube nozzle. To reduce or avoid a wear of the double-tube nozzles and the surrounding brickwork, the flow rate of the protective fluid is so selected in dependence on the composition of the slag and on the difference between the temperature of the slag and its solidification point that crusts will be formed on the nozzles but will not exceed a desired thickness.

Abstract: A system for controlling the voltage of an electrofilter of the type which, after a voltage breakdown, substantially reduces the magnitude of the electrofilter voltage. After a predetermined deionization time, the filter voltage is raised to a new level which is lower than the filter voltage at which the initial voltage breakdown occurred, by a predetermined amount. The filter voltage is subsequently raised in accordance with a predetermined voltage-time function until a further voltage breakdown occurs. The electrofilter voltage is controlled by a microcomputer system in accordance with stored control parameter values. The stored control parameter values are advantageously recalled to control the electrofilter voltage in response to the operating state of a plant in which the electrofilter is employed.