Abstract:
A method for reducing oxidic slags and dusts possibly loaded with organics uses an inductively heatable coke bed extending in the axial direction and having a temperature gradient. Reaction gas is sucked off in an axial region of the coke bed between two induction bodies and metal regulus and slag melt are tapped on the lower end. An inductively heatable shaft furnace chargeable with a lumpy coke bed for the reduction of metallic slags is made of an electrically insulating refractory material, has an adjustable temperature gradient includes at least one cooled induction body on the head side, a suction connection in an axial region where the prevailing temperature exceeds the condensation point of the substances to be removed, located below the cooled induction body on the head side, and an opening for tapping metal regulus and slag melt is provided on the lower end of the furnace.
Abstract:
In a device for melting precrushed material and/or dusts such as, e.g., furnace dusts or steel dusts, marl and lime dust mixtures, shredder light fractions and/or crushed waste substances, in which the material and/or dusts are injected into a combustion chamber along with a carrier gas, the dusts and/or are introduced axially, and the carrier gas is introduced tangentially, into a cyclone 3. The cyclone 3 is connected with a combustion chamber (8) via a substantially axially directed discharge opening (9).
Abstract:
In a device for atomizing liquid melts, in particular oxidic slags or glasses, including a slag tundish and an outlet opening into which a lance is immersed to inject gases or vapor while forming an annular gap, the lance (3) is comprised of two coaxial tubes (4, 5) which are separately displaceable in the axial direction and fixable in their respective axially displaced positions.
Abstract:
In a process for granulating and comminuting molten material, the slag melt is acted upon by compressed water and discharged together with the vapour formed. The liquid slag is introduced into a granulation chamber in a free flowing jet while directing compressed water jets against the slag jet, whereupon the solidified and granulated slag is conducted through a pneumatic conveyor duct and a distributor along with the vapour formed. The partial streams leaving the distributor, via conically tapering nozzles are transferred into a grinding space exhibiting a lower pressure than the granulation space and from which the comminuted and solidified material is drawn off.
Abstract:
A method for processing solid waste incineration residues is disclosed in which the residues are introduced a steelworks slag bath in a sufficient amount so that the residues constitute from 15-45% by weight of the combined weight of the solid waste incineration residues and the steelworks slag bath. The residues are melted to effect the evaporation of heavy metals; which are drawn off from the steelworks slag bath to leave a heavy-metal-depleted slag bath. The residual bath is reduced with carbon carriers to form a slag phase and a pig iron phase. The slag phase can be granulated to produce mixed cement components.
Abstract:
The cement composition of this invention includes 10 to 35% by weight of portland cement, 65 to 90% by weight of a synthetic pozzolan, and an activator for reducing the positive surface potential of the synthetic pozzolan. The synthetic pozzolan is obtained by an at least partial reduction from combustion residues having a SiO.sub.2 /CaO ratio of greater than 1:1 and containing Na.sub.2 O and K.sub.2 O as alkali oxides in an amount exceeding 1.5% by weight. The activator includes anionically active or anionic tensides.
Abstract:
In a process for producing pig iron, nonferrous heavy metal alloys, ferrochromium carbure or carbon-free ferrochromium and synthetic blast furnace slags, using metal-oxide-containing waste incineration residues or slags, the charging materials of waste burning, e.g., car shredder light fractions and/or metallurgical dusts, are at least partially oxidized and subsequently are reduced while separating nonferrous metals or alloys, whereupon the oxidic slag phase depleted from metals or alloys is mixed with liquid steelworks slag optionally upon further addition of metallurgical dusts, whereupon crude steel is drawn off while lowering the viscosity of the steelworks slag and the remaining slag portion is subjected to further reduction while recovering pig iron and optionally Fe chromium alloys, whereupon the resulting synthetic blast furnace slag is discharged.
Abstract:
In the process for treating slag from refuse incineration plants, the crude slag, after passing through the firing grate, is separated into at least two fractions directly and without previous quenching in a water bath. These two fractions are further processed separately, the coarse fraction being fed to a wet deslagger. For optimum separation of the two fractions, the first fraction, having a particle size preferably up to 32 mm, is separated off in a first screening stage and the screen oversize of the first screening stage is fed to the wet deslagging. The screen undersize and if appropriate the material passing through the firing grate are fed to a second screening stage to separate off the fine fraction 0 . . . 2 mm. The screen oversize of the second screening stage, if appropriate after removing metallic and inert materials, is mechanically comminuted. In an optional third screening stage (8), the fine fraction 0 . . . 2 mm is fed together with the screen undersize of the second screening stage to a special treatment.
Abstract:
In the processing of mainly inorganic refuse incineration products polluted by heavy metals and/or heavy metal compounds, and/or analogues of such products, to give environmentally acceptable products by melt-thermal treatment, an iron-containing melt is used whose iron content can be adjusted by addition of iron or an iron compound. The melt is first melted above 1300.degree. C. in a reactor. The melt is then oxidized with vigorous agitation by blowing in oxygen-containing gas until all the metals and metal compounds present in the reactor have been converted to the oxide form, the melt being kept above 1450.degree. C. and preferably at about 1500.degree. C., at least at the end of the oxidation. Subsequently, the melt is reduced, preferably by means of a part fraction of the refuse incineration product and/or iron, preferably in the form of scrap, and/or hydrogen. The reduction can then be continued by means of added aluminum and/or calcium and/or ferrosilicon. If appropriate, metal melt is fractionated in a lower part of the reactor and slag melt is separately collected as a supernatant layer. Heating energy can be saved by heat exchange and recirculation of fluid.