Document 4JXo40OVgNx4qa9Xk7xKV946G

A general view of Gypsum, Lime and Alabastine's modern mineral wool bait plant at Caledonia, Ont. The cupola is housed in the raised portion of the building on the extreme right. OUTSTANDING success in the mineral wool industry, and in their early endeavors in the plant is in many respects a fine S mineral wool production, example of the resurgence which combined with a tremen seems to be in progress in manv dous demand for the ma phases of Canadian industrial ac terial, has led to the constructiontiovfity. an ultra-modern, high-capacity plantThe company's initial undertak ing in the mineral wool field dates By WILLIAM M. AVERY bv the Canadian firm of Gypsum, Lime and Alabastine. located at Caledonia, Ontario. The new fa cilities, which went into production in June, 1946, incorporate a num ber of features which are quite new Below, left: The. base of the 38-in.-di ameter cupola, showing molten streams of rock being blown into mineral wool fibers with high-pressure steam. Right: The discharge end of the blow room, which has oscillating side panels to form the neat edges which can be seen as the strip passes Into the annealing furnace. The edges have not been trimmed at this point. back to 1936, when plain white wool (without binder) was first produced from high-silica limestone. Although the whiteness of the product was un questionably desirable from the sales standpoint, there were certain dis advantages in the use of limestone as compared with slag. Recovenran around 60 percent, as against an average on most slag operations of 83 to 90 percent. Apart from this, wide variations in the chemical an alysis of the limestone caused a mul titude of production headaches. Ex tensive experiments with this lime stone cupola, in which even clay was used successfully for a time, satis- j 64 Pit and Quarry i titdjtlic lompuny Hint mineral wool amid be produced from practically t .me material containing at least -10 percent silica. To increase the recovery rate, however, the second cupola installed in 1941 was designed to operate on -lag. and the following year the original cupola was converted to lag. Initially the company's entire -lag requirement had to be shipped bv rail from Buffalo, but subsequent ly a slag-processing plant was estab lished at Hamilton. Ontario, and a portion of the supply is now trucked from that locality. The new production unit, which at present produces only batts, is housed in an entirely new fireproof building in which provisions have been made for a total of four cupo las. The single cupola now in opera tion is 48 in. in diameter (compared with afi in. on the older units) and about 20 ft. in height. Designed hv the company's own engineers and built by the Hamilton Bridge Co., it is completely watcr-jackcted and utilizes a Foster-Wheeler heat ex changer to effect a 20-degrcc drop in the temperature of the cooling a ter. The cupola is fed continuously at the rate of about two tons per hour, using a 2- to 4-in. slag in the ratio of 4J4 parts (by weight) to 1 ot coke. When better coke becomes I .nailable, the company expects to be able to increase this ratio to about 5yk to 1. The raw materials arc drawn from bins, blended with up to 2 percent sandstone to lift Below, left: Vapor seal, from reels lo cated in the concrete pit under the produc tion line, is applied to the bottom surfaces of the 15-in. strips. Below, right: Thirty-six inches of wool is compressed into a 24-in, carton by forcing the carton through this double-frame roller conveyor. Resiliency, imparted to the ma terial by the binder used, prevents any permanent compression of the fibers. A general view of fhe 56-ft. oil-fired annealing furnace where the binder is set. Tempera tures in this unit are thermostatically controlled, and both surfaces of the blanket are an nealed by means of updraft and downdraft sections. *. fSui Sv- S4: A view of the power-driven bend saw which automatically cuts the strips into 4-ft. lengths. In the background is the platform scale on which the packed cartons are check-weighed. t !< il i : iI I the silica content, weighed and ele downward stroke of the band saw vated to the top of the cupola by is actuated by a limit switch located an 18-in. belt conveyor. on the extreme end of the runout The meft is carried out at a tem conveyor, assuring remarkable ac perature of around 2,700 degrees F. curacy and uniformity in the length and the^molten rock is discharged of the finished batts. The finished continuously through four nozzles product, sold under the trade name at the base, of the cupola. Fibers Gyproc Wool, is packed in 24-in. are produced in the usual manner and 48-in. cartons which arc check- by blasting the molten material with weighed on a Fairbanks Springless high-pressure steam as it flows from scale. the cupola. The asphaltic binder, In a typical 22-hr. run this plant which imparts the dark brown color was charged with 9 tons of coke and associated with mineral wool, is in 36 tons of slag, which yielded 32)4 troduced at the moment the fibers tons of finished wool for a recovery are formed. rate of 91 percent. Although most The fibers enter a blow room producers of the material would which is about 12 ft. high, 35 ft. long consider 91 percent a quite satis and a little over 5 ft. wide. Here factory recovery, this company wants the wool is pulled down by means and expects to increase the rate. of a 25-hp. fan which continuously exhausts about 25,000 cubic feet of Highest recovery, of course, is achieved when the plant is produc air per minute. ing 4-in. batts, the rate drops slightly From the blow room to the final cutting operation the blanket of min eral wool moves on a continuous Wickwire-Spencer chain belt driven by a 5-hp. Reeves Varispeed Moto drive. The strip, measuring 60)4 in- ,, in width, passes from the blow room for 3-in. and 2-in. batts, and mayfall materially, on 1-in. In 24 hours the new production line (which is designated as plant No. 3) turns out about 2,000 cartons of finished batts, employing about 22 men on each shift. This output into, a 56-ft. oil-fired annealing fur nace (designed and built by J:- ' Cinnabar Operation Campbell Smith) where the binder - (From page 63) is set at temperatures ranging be plus 10 liters (2}4 gal.) of diesel tween 600 and 700 deg. F. Accurate fuel oil per metric ton of lime to temperature control is effected by make steam for atomizing the crude dividing the 10 burners into two oil. According to the handbooks groups of 5 each; one group oper this didn't make sense, but on each ates constantly, while the other is test it came out very nearly the thermostatically controlled. same. In order to anneal both sides of the blanket the oven is divided into sections, with a rising stream of air in the front portion and a down ward stream in the back portion. Additional control of the annealing conditions is effected, by varying the speed of the fan drive motor. In order to prevent disarrangement of the fibers, the blanket during its The lime production per ton was more profitable than the mercurybusiness, but the demand at this locality was very limited. From this beginning with work, patience and considerable expense the Nelsons have evolved a stand ardized furnace unit which is neat, exacting, positive in performance and modem in every respect. passage through the annealing fur nace is held between upper and lower chain belts. The strip of min Choctaw Lime Plant to Have 300-400-Ton Daily Output eral wool passes from the furnace At Ft. Towson, Okla., the Choctaw into a 15-ft. cooling chamber in which the temperature is reduced about 200 degrees. Power-driven circular knives, lo cated just beyond the cooling cham Lime Company is currently erecting a crushing plant for the production of agricultural limestone. Capacity is ex pected to be from 300 to 400 tons daily. J. W. Trieschmann Sr., whose son, J. Wemcr Trieschmann Jr., is his partner, ber, split the blanket into four 15-in. has operated a lime plant at St. Joe, strips. Since the material is fully Ark., a crushing plant at Eureka Springs cured at this point, there is a ready market for the comparatively small amount of bulk side trim which is and a sand plant at Caruthersville. Mo. J. W. Trieschmann Jr. will be in charge of production at the Ft. Towson plant. created in the splitting operation. Vapor seal, heated electrically to 300 or 400 deg. F.. is applied to the bottom surfaces of the strips, which are then cut into 24-in. and 48-in. Basic Refractories Offers New Refractory and Gun "Gunchrome," an air-emplaced refrac tory designed to speed up steel produc tion by reducing "down-time" for main lengths by a power band saw. The taining and repairing open-hearth fur- 66 is about 50 percent higher than that ot the No. 2 batt plant, which em ploys about the same number of men, and is roughly comparable in other respects except for the size of the cupola. Both the older cupolas are 3b-in. in diameter as compared with the 48-in. measurement of the newest unit. The company's No. 1 plant, incorporating the cupola orig inally designed for limestone, pro duces granulated wool at present. The new plant is one of the clean est mineral wool production units we have visited. Particularly re markable is the almost complete ab sence of fly, an accomplishment that it not only reflected in the high re covery rate but contributes materi ally to the working comfort of the employees. L. V. Robinson is general super intendent of Gypsum, Lime and Alabastinc's varied operations. J. E. Gillespie is assistant to the general superintendent, J. M. Hagan is plant superintendent and Reg Hudspeth is superintendent of rock woo! plants. The company's director of quality and research is M. C. Haller. naccs, has been announced by Basic Re fractories, Inc., of Cleveland, O. The product is made from Cuban chrome ore. Highlighting the opening day meeting of the Open Hearth Committee of the American Institute of Mining and Metal lurgical Engineers at Cincinnati, April '-.If- *34,^ Y-.All-"A -/ V.T *.W; 'V-'fci ^ The new refractory gun. 21, was a special demonstration of the new B.R.I. gun developed by Basic Re fractories. This gun was primarily designed to speed the application of "Gunchrome and similar materials to vertical and semi-vertical furnace brickwalls at tim r.itc of rnnf than li)H pound* per minute. Pit and Quarry J MTC 017209 PaJZ J J MTC 017210