This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1921 Excerpt: ... ft. diameter lest the blast fall properly to penetrate to the center and maintain intense combustion there. The slope or angle of the bosh-wall must be such as to give proper support to the charge, which rests upon it, and yet allow the solid coke to slip down; an angle of 80 is preferred. The height is limited to the ...
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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1921 Excerpt: ... ft. diameter lest the blast fall properly to penetrate to the center and maintain intense combustion there. The slope or angle of the bosh-wall must be such as to give proper support to the charge, which rests upon it, and yet allow the solid coke to slip down; an angle of 80 is preferred. The height is limited to the height of the smelting zone. These conditions limit the diameter of the bosh to 22 ft. From the top of the bosh the stack wall must decrease in diameter to the throat to give room for the descending charge to swell by reactions that occur in its downward progress. This leaves, at the throat, a diameter suitable for the proper distribution of charge. Furnaces have been built higher than 100 ft., but such height has been found to be excessive, especially for fine ores; and the best practice calls for 90 ft. or less. GAS CLEANING The top gas coming away from a blast-furnace, especially when smelting fine ore, carries much dust caused by the agitation of the blast. Some of this is settled out in the dust-catcher, but the gas still remains quite dusty. When the gas is subsequently burned at the stoves the dust settles in the checker work and at the boilers it attaches itself to the stoves. If the gas is cleaned it burns more efficiently and, moreover, it can then be used for driving a gas-engine blower plant. Fig. 157 gives the views of a scrubber plant for gas cleaning for stoves and boilers for two furnaces. Of the figure, W, is a front elevation, X, a side elevation, Y, a separate elevation of the dust-catcher, and Z a plan view of one of the scrubbers, to show the arrangement of the water sprays. The gases from the dust-catchers of the two furnaces are united in the 7-ft. gas main, a, to go to either of two dust-catchers, b, each leading to th...
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