Abstract:
The present invention relates to a process for electrochemically winning or refining copper by electrodepositing copper from an electrolyte solution containing the metal in ionogenic form, in which the electrolyte is passed through an electrolysis plant comprising at least one electrolytic cell, which in an electrolyte tank for receiving the electrolyte has at least two electrodes serving as anode and cathode, which are alternately arranged at a distance from each other, and to a corresponding plant. To increase the economic efficiency of such processes and plants, it is proposed in accordance with the invention to immerse the at least one cathode during operation of the electrolysis into the electrolyte over a length of at least 1.2 meters.
Abstract:
To protect a plate-type heat exchanger (1) against corrosion due to the attack of sulfuric acid, it is proposed in accordance with the invention that the region through which flows sulfuric acid has at least one metal cathode (16, 17) and one reference electrode (27), that at least half the metal plates (7) have an electric contact (23) which is connected with the anode (21) of an electric d.c. voltage source of variable electric voltage, that the metal cathode (16, 17) likewise is electrically connected with the d.c. voltage source, and that the d.c. voltage source belongs to a potentiostat (20) which is electrically connected with the reference electrode (27).
Abstract:
Plastic wastes which for at least 80 wt-% contain a polymer or a mixture of polymers from a group including polymethyl methacrylate, polypropylene, polyethylene, polystyrene, polyethylene terephthalate and/or polytetrafluoroethylene, are recycled using the following steps: (i) heating the plastic wastes to a temperature at which they are flowable; (ii) pyrolyzing the flowable plastics together with a catalyst and/or an adsorber and withdrawing the resulting gases; (iii) condensing the gases.
Abstract:
This invention relates to a method for the thermal treatment of granular solids in a fluidized-bed reactor (1), in which microwave radiation from a microwave source (2) is fed into the reactor (1), and to a corresponding plant. To improve the utilization of energy and the introduction of the microwave radiation, a first gas or gas mixture is introduced from below through a preferably central gas supply tube (3) into a mixing chamber (7) of the reactor, the gas supply tube (3) being at least partly surrounded by a stationary annular fluidized bed (8) which is fluidized by supplying fluidizing gas. The microwave radiation is supplied to the mixing chamber (7) through the same gas supply tube (3).
Abstract:
This invention relates to a process for producing cement or cement substitutes on the basis of carbon-containing compounds with a carbon content of more than 10 wt-%, wherein the carbon-containing compounds are burnt in a furnace at a temperature of 600 to 900°C, and wherein beside the carbon-containing compounds at least one additional, inert and/or low-heating-value material, which already before or after a thermal treatment has cement properties, is introduced into the furnace and calcined.
Abstract:
For refining oil-containing solids, in particular oil sand or oil shale, there is proposed a process with the following steps: supplying the oil-containing solids to a reactor and expelling an oil- containing vapor at a temperature of 300 to 1000 °C, - supplying the oil-containing vapor expelled in the reactor to a cracker, in which the heavy oil components are broken down, separating the products obtained in the cracker and withdrawing the product streams, introducing the solids left in the reactor including the unevaporated fraction of heavy hydrocarbons into a furnace, burning the heavy hydrocarbons left in the solids in the furnace at a temperature of 600 to 1500 °C, preferably 1050 to 1200 °C, recirculating hot solids from the furnace into the reactor, wherein the oxidizing atmosphere of the furnace is separated from the atmosphere of the reactor by a blocking device.
Abstract:
This invention concerns an electrolytic cell equipped with several bipolar electrodes which are connected in series during operation of the cell. Each of the bi-polar electrodes has a cathode side (K7, 8) and an anode side (A7, 8) between which an electrically conducting connection (11, 12) is established during operation. At least one bipolar electrode has a cathode side and an anode side which are displaceable towards one another. In particular, either the cathode side or the anode side can be separated and removed from the electrolyte.
Abstract:
The production of calcined clay is effected by using a plant known per se for producing cement by the dry or semiwet process, with a precalciner (1), for instance comprising at least one preheating line of series-connected preheating stages (2), such as cyclone preheaters or grate preheaters, and a rotary kiln or roaster (3). In accordance with the invention, the rotary kiln or roaster (3) for generating heating gas is utilized as combustion chamber (31), replaced by a combustion chamber (3') and/or completed by an additional combustion chamber.
Abstract:
In accordance with the invention, refining raw materials containing organic constituents, such as solids containing oil and/or bitumen, in particular oil or tar sand or oil shale, is effected with the following steps: - supplying the raw materials to a reactor and expelling fuel gases at a temperature of about 300 to 1000°C, preferably about 500 to 800°C, introducing the solids left in the reactor including the non-evaporated fractions of heavy hydrocarbons into a furnace, burning the heavy hydrocarbons left in the solids in the furnace at a temperature of 600 to 1500°C, preferably 700 to 900°C, recirculating hot solids from the furnace into the reactor, wherein the oxidizing atmosphere of the furnace is separated from the atmosphere of the reactor by means of a blocking device.
Abstract:
For refining oil-containing solids, in particular oil sand or oil shale, there is proposed a process with the following steps: supplying the oil-containing solids to a reactor and expelling an oil- containing vapor at a temperature of 300 to 1000 °C, - supplying the oil-containing vapor expelled in the reactor to a cracker, in which the heavy oil components are broken down, separating the products obtained in the cracker and withdrawing the product streams, introducing the solids left in the reactor including the unevaporated fraction of heavy hydrocarbons into a furnace, burning the heavy hydrocarbons left in the solids in the furnace at a temperature of 600 to 1500 °C, preferably 1050 to 1200 °C, recirculating hot solids from the furnace into the reactor, wherein the oxidizing atmosphere of the furnace is separated from the atmosphere of the reactor by a blocking device.