Which gives for the caloric really developed 0.48 of the calorific power of the coke consumed. The 3816 calories divide themselves between the zones of the furnace as follows:-The carbon burned in the zone of reduction is given by the formula: 3 0.302 + b my 0·302 + 0.082 — 0·326 — 0·058.* 11 * It is right to call attention here to this number. 0·058 absorbed in transforming CO2 to CO is less than the 0·082 of carbon in the limestone, which proves, contrary to Mr. Bell's opinion, that the whole carbonic acid of the limestone is not necessarily transformed to CO in the blast furnace. Hence the carbon burned near the twyres 0·990-0-058 0.932, and the caloric produced in this region: The caloric given off in the zone of reduction arises from (1.) The carbon burned to CO, = 0·058 × 2473 (2.) The CO burned to CO2, 144 cal. ·3 三 * (my-6) × 2403 1511 “ Caloric produced in zone of reduction Or, to sum up, caloric produced near the twyres 2305 cal. Do. do. zone of reduction Total caloric produced by combustion Caloric carried in by the blast. And hence, total caloric received 1511 3816 cal. 602 cal. 4418 cal. We can already perceive, by comparing this total of caloric received with that of the first example, § 16, that to produce the same useful effect, the supply to this second furnace is 517 calories less, and the difference is altogether in the caloric of the region of the twyres. The caloric generated in the zone of reduction is even 208 calories more in the large furnace than in the small. Let us now estimate the caloric absorbed. (1.) For the reduction of the ores, and the fusion of the pigiron pr.. (2.) For fusion of slag and decomposition of limestone, etc., § 12 gives: 2314 cals. § 18. Third example.-As third example, we take with Mr. Bell the Ormesby blast furnace, built in 1867 (fig. 8). The elements of this furnace are: Height, 76 feet; capacity, 20,500 c. feet. As at Clarence Works, the ores smelted are calcined Cleveland ores. The yield is 63 tons of pig, Nos. 3 and 4, in 24 hours, which corresponds to 326 cubic feet capacity per ton of iron: Coke consumed per ton, 1.100 tons, or of pure carbon, 1·017 t. Ore 2.440" * 0·237 is, according to § 16, the mean specific heat of the gases. And from these data we deduce per each lb. of iron yielded: Carbon of coke, a = 1·017 Carbon of limestone, b = 0.12 × 0·625 0.075 On the other hand, the analysis of the gases gave m = 0.542. With these data, the formulas of 8 7 give the following results: Caloric produced in the Furnace. Caloric due to CO2: 6) 8080 = = 7Y × 2473 0.790 × 2473 Caloric due to CO. 1954 " Caloric produced by 1.062 -0.075 01·987 carbon 3546" And hence, caloric produced per lb. carbon . 3593 66 And this gives for the caloric really developed 0-44 of the calorific power of the coke consumed. These 3546 calories are divided in the following proportions. between the two zones of the furnace. The carbon burned in the zone of reduction is given by 0lb.1050-882, and the caloric produced in this region, 0.882 × 2743 = 2181 calories. The caloric generated in the zone of reduction arises from (1.) carbon burned to CO 01b 105 x 2473 = . = (2.) CO transformed to CO2, 260 cals. Caloric taken in by blast Caloric produced in zone of reduction Or, en résumé, Caloric produced near twyres Caloric from zone of reduction Total caloric from combustion Total caloric received by the furnace 4459 " |