Slagging

An additive assisting in fusion - e.g. CaCOj in iron-smelting - although the limestone also helps with slag formation. 

Fig. 5 dives an image of a steel plate weld 18 mm thick. The sensitivity is of the first accuracy class. Both gas pores, slag inclusions and a cut have been detected in this weld... 

Sampling of checkpoints during the review exercise confirmed some predictable features, notably that radiography would miss planar defects such as lack of side wall fusion, and that ultrasonic operators tended not to report undercut, porosity or the smaller slag inclusions. 

The gases from the kiln contain about 9% sulphur dioxide. (The calcium oxide combines with the silica to form a silicate slag which, when cool, is crushed and mixed with some anhydrite to give cement, a valuable by-product.)... 

Reaction (13.4) is exothermic and reversible, and begins at about 700 K by Le Chatelier s Principle, more iron is produced higher up the furnace (cooler) than below (hotter). In the hotter region (around 900 K), reaction (13.5) occurs irreversibly, and the iron(II) oxide formed is reduced by the coke [reaction (13.6)] further down. The limestone forms calcium oxide which fuses with earthy material in the ore to give a slag of calcium silicate this floats on the molten iron (which falls to the bottom of the furnace) and can bo run off at intervals. The iron is run off and solidified as pigs —boat-shaped pieces about 40 cm long. 

Anglo-Saxon, Seolfor siolfur L. argentum) Silver has been known since ancient times. It is mentioned in Genesis. Slag dumps in Asia Minor and on islands in the Aegean Sea indicate that man learned to separate silver from lead as earl as 3000 B.C. 

The determination of silicon is commonly encountered in metallurgical and mining laboratories responsible for the analysis of ores, slags, and alloys. The volatilization gravimetric method, which is appropriate for samples containing high concentrations of silicon, was described earlier in Method 8.2. 

Ashing Ashphaltenes Ash properties Ash slagging Asmatane Mst ASN As203... 

Slag scrap Slagsitall Slagwool Slated sulfur S Lec... 

Titanium silicalite Titanium silicates Titanium-silicon alloy Titanium slag Titanium suboxides... 

Deposition rates using this process are limited by the fact that each electrode contains a finite amount of filler metal. The time required both to change electrodes and to remove the slag coating between each weld pass lowers the overall productivity of the process. 

The integrity of welded stmctures depends on the integrity of the welds, and much attention is given to testing methods, such as destmctive tests, nondestmctive tests, and general weld inspection. An objective of many tests is to determine whether welds contain specific defects, such as porosity, slag inclusions, cracks, or lack of fusion (14,15). 

Fig. 8. World trends in types of phosphate fertilizers consumed, where (—) represents ammonium phosphates and multinutrient compounds (— normal superphosphate ( ), triple superphosphate and (— —), basic slag and raw rock.

Calcium. Calcium is the fifth most abundant element in the earth s cmst. There is no foreseeable lack of this resource as it is virtually unlimited. Primary sources of calcium are lime materials and gypsum, generally classified as soil amendments (see Calcium compounds). Among the more important calcium amendments are blast furnace slag, calcitic limestone, gypsum, hydrated lime, and precipitated lime. Fertilizers that carry calcium are calcium cyanamide, calcium nitrate, phosphate rock, and superphosphates. In addition, there are several organic carriers of calcium. Calcium is widely distributed in nature as calcium carbonate, chalk, marble, gypsum, fluorspar, phosphate rock, and other rocks and minerals. 

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