| 摘要 |
The invention concerns a process and en apparatus for producing metal from metal ores, in particular crude or pig iron from iron ore, in which the ore which contai ns metal oxides is brought into reaction contact with a reducing gas which contains carbon and/or hydrogen (and possibly compounds thereof) and which was previously obtained from solid, carbon-bearing and/or hydrocarbon-bearing substances, It is known that the o re which for the major part comprises metal oxides (being various ones, even in the case of iron) must be subjected to a reduction procedure before the metal can be obtained. Taki ng the known process as set forth in the opening part of this specification as its basic starting point, the object of the invention is to make plastic waste, including in organically and/or inorganically contaminated form, useable as a supplier for the constituents of the reducin g gas. Plastic waste occurs constantly in large amounts and represents a serious disposal problem. It occurs mostly if not exclusively in solid form, either as packaging waste - which is frequently heavily contaminated -, or as offcuts or the like in the course o f the production of plastic articles. Accordingly the invention provides that the carbon- bearing and/or hydrocarbon-bearing substances, at least partially comprising plastic material, which in the process of the general kind set forth in the opening part of this specification are supplied to obtain the reducing gas, are injected in comminuted fluidised form as an agglomerate into the air flow in the hearth of the metallurgical shaft or pit furnace, i n particular a blast furnace. That is effected by way of lances which project into the shaft furnace and which are connected to a transport conduit. The plastic material to be injected is fed to the lances by way of that transport conduit. In the event that, contrary to expectation , blockages should occur or hot air should blow back out of the blast furnace into the lance and thus into the transport conduit, a plurality of shut-off or check devices are proposed in the transport conduit, so that the transport conduit is not only protected but immediate resumption of overall operation of the installation and injection of the plastic materials occurs. To dissolve blockages of the plastic material in the transport conduit, there are provided a first and third shut-off device, while a second shut-off device i s provided to prevent reverse transportation of plastic material or blow-back of the hot g as masses from the blast furnace into the transport conduit. The mode of operation thereof is set forth in greater detail in the claims but in particular also in the specific description.
|
