Slag bath reactor

The top submerged lance-slag bath reactor for injection of gases and fuel into a slag bath was developed in Australia by the Commonwealth Scientific and Research Organisation (CSIRO), and was termed the SIROSMELT Process. The original aim was to avoid the refractory problems... 

Concentrates and flnxes are mixed in a paddle mixer and fed via a weigh feeder directly into the slag bath reactor. Wet feed is satisfactory, eliminating any need for drying, but high moisture will consume more fuel and increase the volnme of smelter gases. 

As an alternative to the conventional slag fuming furnace, a top submerged lance slag bath reactor may be used for zinc fuming. In this process fuel as gas, oil or pulverised coal is injected with oxygen... 

Top-submerged lancing (TSL) - slag bath reactor operating principles and construction... 

Operation of the slag bath reactor in a continuous mode is feasible and in this case it is practical to nse multiple stages in series with slag flowing from one reactor to another. This can increase the overall fuming rate for a given reactor volume but is also useful to separate gas streams if the feed material contains sulfur. 

Direct smelting processes provide alternatives to the sinter plant-blast furnace above, up to the stage of crude bullion production, but still require the addition of refining operations to produce high-grade lead. Three alternatives have been evaluated - the Kivcet process, the QSL process and the Isasmelt process - as typical of the top submerged lance slag bath reactor. Evaluations are based on comparable feeds, predominantly lead concentrates with low residue inputs. 

The cylindrical reactor can be rotated through 90° when the process is interrupted to lift the injectors clear of the slag bath. This also allows access to the injectors for maintenance or replacement. Injector life is relatively short and has been quoted for the Stolberg unit at 800 hours for the oxidation section and 1300 hours for the reduction section. Overall plant availability was given as 85 per cent. 

ARP [Advanced Reactor Process] A process for making aluminum metal. A molten slag bath containing alumina and carbon produces aluminum carbide that is reacted with more alumina. Under development by Alcoa and Elkem Technology, but not commercialized by 2011. See also Thermical. 

In this type of combustion facility pulverized coal is burned with air in a reactor in the form, for example, of a horizontal cyclone. In this reactor high temperatures of ca. 1600°C are achieved and the ash components of the coal are melted to form slag. The liquid slag collects on the reactor wall as a result of the fluid-flow characteristics in the reactor. It flows out of the reactor through the tap hole and is then granulated in a water bath. The waste gas is cooled in boilers, whereby high-pressure steam is produeed, which is used to drive steam turbines for power generation. 

For a reactor containing 1 m slag depth, the slag contained is approximately 3 t/m of cross-section and the zinc depletion rate is thus of the order of 0.121 of zinc fumed per hour per square metre of furnace cross-section. This represents a crude indication of reactor capacity only, as gas flow rates are also a major determining parameter and can differ significantly from the conventional slag fumer in relation to bath cross-sectional area. 

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