. Transactions. flue-dirt gave the following results, whichshow that most of it was coke :—Loss on ignition, ; Si02,; Fe203, ; A1203, ; CaO, ; and MgO, percent. The coke in the bins was very dirty and badly broken, andit was apparent that the coke in the hearth of the furnacewas so finely divided that the slag found great difficulty in set-tling through the mass, particularly during a slip; hence^ theflooding of the tuyeres with cinder and iron, and their conse-quent destruction. K-DIS1 RIBl I l-\ IND BL \81 FURN \« i: LINN _I7 In tan, it was »iilv after long blowin
. Transactions. flue-dirt gave the following results, whichshow that most of it was coke :—Loss on ignition, ; Si02,; Fe203, ; A1203, ; CaO, ; and MgO, percent. The coke in the bins was very dirty and badly broken, andit was apparent that the coke in the hearth of the furnacewas so finely divided that the slag found great difficulty in set-tling through the mass, particularly during a slip; hence^ theflooding of the tuyeres with cinder and iron, and their conse-quent destruction. K-DIS1 RIBl I l-\ IND BL \81 FURN \« i: LINN _I7 In tan, it was »iilv after long blowing at the cinder-notch, andrepeated checkings of the blast thai the tuy< »uld be dried sufficiently to take off the blast without filling the blowpipe The first effort made to reduce the tuyere-destruction was theincrease of the feed-water pressure by changing from the regu-lar tank-service of salt water at :!»i ll». to the fresh-water mamat 40 lb, per sq. in. This made only a Blight improvement Fio. Top of Furnace No. 1. Fir^t Campaign. Next was the steady increase of the number of ensrine-revo-lutions, until an average of 36,000 cu. ft. of air per minute,measured by piston-displacement, was forced through thetuyeres. After this change the slipping was less frequent, theoutput greater and, at the same time, no more tuyeres werelost. Finally, silica rock was introduced in the charge, which hada marked effect, making the slag very fluid, reducing the burn- VOL. xxxv.—16 248 STOCK-DISTRIBUTION AND 151,AST-FURNACE LINING, ing-out of the tuyeres materially and increasing the output greatly. The besl results were obtained by the addition of200 lb. of quartz-gravel for cadi ton of ore charged, changingthe slag-analysis from to per cent, of Si02, and to per cent, of A1203. At that time, dolomite wasiised as a flux. The ore obtained from Wabana, Belle Isle, Conception Bay,Newfoundland, is a uniform, dense, red hematite, which hasbeen split up i
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Keywords: ., bo, bookcentury1800, bookdecade1870, booksubjectmineralindustries
