Kettle furnaces

The pyrometaHurgical processes, ie, furnace-kettle refining, are based on (/) the higher oxidation potentials of the impurities such as antimony, arsenic, and tin, ia comparison to that of lead and (2) the formation of iasoluble iatermetaUic compounds by reaction of metallic reagents such as 2iac with the impurities, gold, silver and copper, and calcium and magnesium with bismuth (Fig. 12). 

Typical applications in the chemical field (Beaver, op. cit.) include detarring of manufactured gas, removal of acid mist and impurities in contact sulfuric acid plants, recovery of phosphoric acid mists, removal of dusts in gases from roasters, sintering machines, calciners, cement and lime Idlns, blast furnaces, carbon-black furnaces, regenerators on fluid-catalyst units, chemical-recoveiy furnaces in soda and sulfate pulp mills, and gypsum kettles. Figure 17-74 shows a vertical-flow steel-plate-type precipitator similar to a type used for catalyst-dust collection in certain fluid-catalyst plants. 

Kessel-niederscUag, m. deposit in a kettle, boiler or reservoir, -ofen, m. pot furnace crucible furnace. -rohr, n. boiler tube, -spaonung,/. boiler pressure, -speisewasser, n. boiler feed water, -speisimg, /. boiler feeding, boiler feed. 

These two reactions are reversed when water containing Ca(HC03)2 is heated in a kettle or furnace ... 

Furnaces, direct fired 1.3 kettles, carbon steel 1.9... 

At PPG Industries in Lake Charles, Louisiana, numerous instrument loops provide critical safety, alarm, and shutdown functions. These protective instruments are located on reactors, oil heaters, incinerators, cracking furnaces, compressors, steam-heated vaporizers, kettles, distillation columns, boilers, turbines, and other critical equipment. Process analyzers and flammable vapor detectors also enhance the overall process safety environment. [8]... 

In liquidation, tin is heated on the sloping hearth of a small reverberatory furnace to just above its melting point. The tin runs into a so-called poling kettle, and metals that melt sufficiently higher than tin remain in the dross. Most of the iron is removed in this manner. Lead and bismuth remain, but arsenic, antimony, and copper are partly removed as dross. 

In plants such as oil refineries that have many streams at high temperatures or high pressures, their energy can be utilized to generate steam and/or to recover power. The two cases of Example 1.4 are of steam generation in a kettle reboiler with heat from a fractionator sidestream and of steam superheating in the convection tubes of a furnace that provides heat to fractionators. 

Modern rotary kiln plants have capacities of up to ca. 500 t/d, continuous grate furnaces up to 1000 t/d. The residence times are less than 1 hour. In kettles throughputs up to 150 t/d with residence times of several hours are aimed for. Box shaft kilns are no longer viable due to the lengthy (several day) calcination times. 

Bell and elevator kilns are often cylindrical. Furnaces for pot, kettle, and dip-tank containers may be fired tangentially with type H flames instead of type E shown. 

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