Rotary furnace

Rotar Furnace. The rotary furnace, which has more flexibiUty than either the blast or reverberatory furnace, can produce either a single metal product or a high and a low antimonial alloy. The rotary furnace, like the reverberatory furnace, allows for the option of producing low antimony lead for further refinement. 

However, rotary furnaces tend to produce more exhaust gas and fumes, require more skill fill manipulation, and are more labor intensive. Also, the slags produced in the rotary furnaces, soda or fayaUte [13918-37-1] slags, normally do not pass the toxic characteristic leach procedure (TCLP) test and pose a disposal problem. 

The barium sulfide needed for the reaction is prepared by the reduction of barite [13462-86-7] BaSO, with petroleum coke in a rotary furnace ... 

Table 1. Aluminum Dross Treatment Using Three Rotary Furnace Technologies ...

Treatment Rotary furnace type Plasma Arc Ceattifuge... 

Indonesia and Singapore use slow-speed rotary furnaces. Both Malaysia and Thailand have added new electric-furnace smelting capacity in order to improve smelting efficiencies. Reverberatory and rotary furnaces are also used in Indonesia. On the other hand, the smelters in Central Africa, including those in Zaire and Rwanda as well as those in South Africa, which are far away from coal sources, use electric furnaces because of the availabiUty of electric power. 

The use of potassium hexafluorosihcate is preferred over sodium hexafluorosihcate because of the lower tendency of the potassium compound to dissociate the lose sihcon tetrafluoride by sublimation. The addition of potassium carbonate or chloride to the fusion mix further reduces this tendency and promotes completion of the reaction. The reaction is conducted in a rotary furnace operating at 700°C. The product is cmshed prior to leaching with acidified hot water. The hot slurry is filtered to remove the sihca, and potassium hexafluorozirconate crystallizes as the solution cools. 

Recycling of antimony provides a large proportion of the domestic supply of antimony. Secondary antimony is obtained from the treatment of antimony-hearing lead and tin scrap such as battery plates, type metal, beating metal, antimonial lead, etc. The scrap are charged iato blast furnaces, reverberatory furnaces, or rotary furnaces, and an impure lead bulHon or lead alloy is produced. Pure lead or antimony is then added to meet the specifications of the desired lead—antimony alloy. 

Most domestic battery scrap is processed in blast furnaces, rotary furnaces, or reverberatory furnaces. A reverberatory furnace is more suitable for processing fine particles and may be operated in conjunction with a blast furnace. 

Trommel-ofcn, m. rotary furnace or oven cylinder roaster, -probe, /. (Coke, Ceram.) rattler test, -sieb, n. drum sieve, cylindrical screen, trommel, -trockner, m. drum drier, rotary drier. -versuch, m. = Trommel-probe. 

Zinc 350-400 Cementation (rotary furnace) 12-50 /im Single-phase intermetallic 80-90% Zn Brittle Spot-welding and soldering possible... 

In the flowsheet of alumina production by the Bayer process, aluminum is precipitated from an aqueous solution as aluminum hydroxide. The hydroxide is dried in rotary furnaces. In recent times, fluidized-bed reactors have been deployed which yield practically nonhygroscopic alumina. The dissociation of aluminum hydroxide occurs in steps,... 

In this process EAF dust, other zinc-bearing wastes, recycled materials, coke or coal, lime, and silica are mixed and fed to a rotary furnace. The zinc and other volatile nonferrous metals in the feed are entrained in the furnace off-gas and are carried from the furnace to an external dust collection system. The resulting oxide (zinc calcine) is a crude zinc-bearing product that is further refined at zinc smelters. A byproduct of the process is a nonhazardous, iron-rich slag that can be used in road construction. Solidification technologies change the physical form of the waste to produce a solid structure in which the contaminant is mechanically trapped. 

Newer secondary recovery plants use lead paste desulfurization to reduce sulfur dioxide emissions and waste sludge generation during smelting. Battery paste containing lead sulfate and lead oxide is desulfurized with soda ash to produce market-grade sodium sulfate solution. The desulfurized paste is processed in a reverberatory furnace. The lead carbonate product may then be treated in a short rotary furnace. The battery grids and posts are processed separately in a rotary smelter. 

Rotary drum vacuum filters, 11 345, 355-357. See also Drum filters Rotary dryers, 9 121-122 indirect-heat, 9 129 steam-tube, 9 129-130 Rotary fiber spinning process, 13 387 Rotary furnace technologies, 21 391 Rotary hearth furnaces, 13 177—178 Rotary impeller vane meters,... 

Potassium formate obtained from purified producer gas (see Potassium Formate) is heated in a rotary furnace having free access to air. 

Another dry process is run continuously [57], The dry, powdered reaction mixture is fed into a rotary furnace kept at 180°C, and the dry product is discharged into a drum at a yield of 96% [36,37], A vacuum method for the preparation of relatively pure CuPc is described in [58],... 

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