The chemistry of plant and animal life . t growth and animal life. Somewaters contain carbonate of iron which, like calciumcarbonate, is soluble in the presence of carbon dioxid ;upon exposure to the air, the iron is precipitated as hy-droxid, forming a brown deposit. Iron takes an im-portant part in industrial operations and its chemistryhas been more extensively studied than that of any otherelement. 179. Reduction of Iron Ores.—Only iron ores of a highdegree of purity are ready, as mined, for the iron ore is concentrated and separated from itsimpurities by magnetic co
The chemistry of plant and animal life . t growth and animal life. Somewaters contain carbonate of iron which, like calciumcarbonate, is soluble in the presence of carbon dioxid ;upon exposure to the air, the iron is precipitated as hy-droxid, forming a brown deposit. Iron takes an im-portant part in industrial operations and its chemistryhas been more extensively studied than that of any otherelement. 179. Reduction of Iron Ores.—Only iron ores of a highdegree of purity are ready, as mined, for the iron ore is concentrated and separated from itsimpurities by magnetic concentrators. The blast-fur-nace used for the production of cast iron is constructedof brick and is shown in Fig. 59. Ore, coke, and flux,usually limestone, are mixed in the right proportion andintroduced into the top of the furnace. The flux is usedto separate the impurities, forming a fusible slag whichis largely calcium silicate. Hot air is forced into thefurnace by means of blowing engines, through tuyeres. IRON, ALUMINUM, ETC. 141. Fig. 59. Blast-furnace (after Hart). 142 AGRICULTURAL CHEMISTRY The carbon dioxid produced first is reduced to carbonmonoxid which passes over the heated ore in the upperpart of the furnace, and is the main reducing agent of theblast-furnace. The carbon monoxid given off at the topof the furnace is collected and used for heating the furnace is constructed so as to utilize the heat to thebest advantage and so that the blast can act slag which carries a large portion of the impuritiesof the ore, being lighter than the molten iron, collects onthe surface and is removed from time to time. Themolten iron is run off from the bottom of the furnaceinto molds ; iron that is produced in this way is knownas pig iron. It contains a number of impurities as phos-phorus, carbon, silicon and sulfur. i8o. Wrought Iron,—Wrought iron is produced fromcast iron by two processes : (i) the puddling processwhich consists of oxidizing the im
Size: 1383px × 1806px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1900, bookpublishernewyorklondonthema
