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Show INTERNATIONAL SMELTING COMPANY Ir 1 " - - '..".' '. - . . ' . . " ,;'.-' '. ; General View of International Smelting Plant From Northwest SMELTINGMILLING DESCRIPTION OF LEAD AND COPPER SMELTER AND LEAD-ZINC LEAD-ZINC CONCENTRATOR OF INTERNATIONAL IN-TERNATIONAL SMELTING COMPANY. The Tooele plant of the International Interna-tional Smelting company is situated at the mouth of Pine Canyon on the western slope of the Oquirrh mountains, moun-tains, five miles east of Tooele City and about 35 miles southwest of Salt Lake City. The plant consists of a lead-zinc flotation concentrator, copper smelter and lead smelter. The reduction plant -site appears on railway maps as "International," the terminus of the Tooele Valley railway, rail-way, which runs west through Tooele City to Warner, on the Los Angeles line of the Union Pacific System, and also on a branch line of the Western Pacific railway. Standard gauge railroad tracks enter en-ter the plant on three levels. The "high line" or receiving tracks are on a level below the concentrator and above the smelting plants. From the "high line" level a single track rises to the concentrator receiving pockets and warehouses. The middle track is used for transferring smelter products pro-ducts and ores from one department to another. Metals shipped from the plant are handled on the lower tracks. The plant treats lead, lead-zinc, copper and dry silver ores, and produces pro-duces blister copper, lead bullion and zinc concentrates. Lead-zinc ores are received mainly from Park City and Bingham, Utah, and from Colorado, Nevada and Idaho. Ida-ho. .Lead ores are received mainly from Tintic, Park City and Bingham, Utah, and from Idaho and Nevada. Copper concentrates are received mainly from California and Idaho, and ores from Tintic and Bingham, Utah. All ore, coke and fluxes handled, with the exception of those ores received re-ceived from the Bingham district over the tramway, together with outgoing products, are shipped over the Tooele Valley railway. TRAMWAY Lead, lead-zinc and copper ores from the mines of the Utah Delaware Mining company and the Utah Metal and Tunnel company in the Bingham district are transported to the Tooele plant over an aerial tramway which passes over the Oquirrh mountains at an altitude of 1450 feet above the loading station at the Highland Boy mine and descends 1800 feet to the terminal bins at the smelter. Intermediate Inter-mediate bins also allow diversion of any ore to the concentrator. The total to-tal length of the tramway is four miles. The ore is carried in buckets of 1200 nn,,,,i i onn foot apart, traveling at a rate of about wO feet per minute. . Upon arrival at the smelter the ore is dumped from the buckets into the concentrator terminal bins of 2000 tons capacity, or into the smelter terminal pins. From these latter bins the ore is drawn into special 50-ton motor dump cars, weighed, and delivered to the smelter receiving bins. SAMPLING MILL Copper, lead and lead-zinc ores received re-ceived from all sources are dumped wto steel receiving bins of a total capacity ca-pacity of 4000 tons. In the case of company ore diverted to concentrator nins every fifth bucket is allowed to Proceed to tram terminal bins for sampling purposes. This is transferred transfer-red by the electric dump cars to the receiving bins. 2n t.haw shed having a capacity of u standard railway cars allows cars j frozen ore to be thawed before "u.mping their contents into the reviving re-viving bins. The temperature is kept at about 120 F. in the shed. T , e sampling mill is a standard iayior and Brunton mill, built in two sections each with a capacity of 100 u"s per hour. The ore is conveyed 1 here from the receiving bins by conveyor con-veyor belts, crushed, mixed, and a representative portion automatically separated as a sample of the lot. This sample is further reduced in size and fineness in the pulping department. de-partment. The resulting sample of a few ounces is sent to the- laboratory for analysis. After sampling, the ores are distributed dis-tributed by belt conveyors to copper plant bins, lead plant bins of lead-zinc lead-zinc plant bins, all in the smelter yards. From the lead-zinc plant bins the various ores are bedded onto a belt conveyor by means of belt feeders feed-ers and elevated into railway cars. These cars are hauled to the concentrator concen-trator and dumped into receiving pockets there. Concentrates do not pass through the sampling mill. They are hand sampled and dumped into bins in whatever department they are to be treated. LEAD-ZINC FLOTATION CONCENTRATOR CON-CENTRATOR From data obtained from over two years of experimental and research concentration work on the lead-zinc-silver ores of this district, it was decided de-cided to suspend copper operations in the concentrator and remodel one 500 tons per day unit to treat the characteristic charac-teristic lead-zinc ores on which the experimental work had been pel-formed. -This remodeling was completed and operations were started as a custom cus-tom lead-zinc concentrator on November No-vember 1, 1924, with a capacity of 500 tons per day. The high lead market stimulated the production of these ores, and it was decided to increase the capacity. Consequently a second unit of 250 tons per day capacity was put in operation op-eration February 4, 1925, which was increased to 500 tons per day on May 1, 1925, since which time the concentrator concen-trator consists of two units, each of which is handling 500 tons per day of lead-zinc ore. The major portion of the material treated comes from the Park City and Bingham districts, the former received re-ceived by rail and the latter by aerial tramway. In addition to the above, considerable tonnage is received from different parts of the state and from adjacent states in relatively small lots. More favorable freight rates are bringing in considerable ore of this character which could not be economically eco-nomically moved prior tothe development develop-ment of this custom operation. Briefly the operation consists of crushing and sampling the ore and to a considerable extent bedding the different dif-ferent ores as above described prior to sending to the concentrator in order or-der to maintain as uniform a feed as possible. Standard practice of ball mill grinding and classification is followed, fol-lowed, and then with different reagent additions, series recovery of the lead, zinc and iron is made in respective concentrates by flotation alone, as well as a Iinal or mill railing wiutu goes to waste. . The concentrator is arranged in two separate and distinct sections, the grinding equipment being identical identi-cal in each, but Section No. 1 is equipped equip-ped with Callow pneumatic flotation cells, while Section No. 2 has mineral separation sub-aeration machines. The ores are treated in the section or combination com-bination of sections in which it has been found the equipment is best adapted as regards metallurgical results. re-sults. The respective finished products pro-ducts from the two sections are combined com-bined for de-watering and disposal. As regards this feature, the lead product pro-duct is sent to the Tooele lead plant, the zinc product to the Great Falls electrolytic zinc plant, and the iron product to either the Tooele lead plant or copper plant as desired for fluxing purposes. The tailings from both sections are thickened to approximately approxi-mately fifty per cent solids and pumped pump-ed into impounding dams. The overflow- or clear water from the thickener is returned to a head tank for general mill use. In this way the only water lost in the operation is that contained in the respective re-spective concentrates, and the thick ened tailing. The loss is made up with fresh spring water. The general concentrator feed will average approximately six to eight per cent lead, eight to ten per cent iron and ten to twelve per cent zinc. From these heads a lead concentrate averaging sixty to sixty-five per cent lead, a zinc concentrate averaging fifty to fifty-five per cent zinc, and and iron concentrate averaging thirty-eight to forty per cent iron are made in this series treatment. Every effort is made to produce as high grade and clean products as possible, and at the same time maintain good recoveries of the lead, zinc and iron in their respective concentrates. A very complete and extensive concentration con-centration testing laboratory is maintained main-tained for frequent checking of ore receipts, testing of new ores for process pro-cess amenability, and for improving and working out of new treatment nrocesses for these same ores. The laboratory is equipped with several sev-eral types of small batch testing machines, ma-chines, and in addition has a Callow test mill and a mineral separation test mill, each of one hundred pounds per hour capacity complete in every way, and patterned identically after the concentrator. Continuous tests are made in this test mill trying out new processes, new reagent combinations, combina-tions, and determining the effect of returning intermediate .products which cannot be done consistently on the regular batch testing machines. This concentrator is especially unique, uni-que, in that it is treating a varying mixture of lead-zinc ores from over fifteen different mines on strictly a custom basis, and making a three-mineral three-mineral separation and concentration from them by flotation alone, and by means of the same treatment process. These ores are of widely different analysis and general character, as would be expected, but their general tendency is to react very similarly to the process employed. It is evident from this fact that such a plant provides a profitable outlet out-let for the mines of this district which have been limited heretofore in their output of ores of this character, due to the often times prohibitive zinc penalty for smelting ores. This is especially beneficial to the relatively small producer who is not justified in putting up his own plant, and at the same time secures profitable returns re-turns from his shipments to such a custom plant operating on a "pay for zinc" rather than a "penalty" basis. LEAD SMELTER Lead ores are received by belt conveyor con-veyor from the. sampling mill and are delivered to steel charge bins having a capacity of 13,000 tons. These bins are divided into two sections, one of which contains the materials for making mak-ing up the sintering plant charge and the other the ores, fluxes and sinter used in making up the blast furnace charge. r.nko fnr the blast furnaces is un loaded from cars standing upon an elevated trestle above a large concrete pit. Coke is withdrawn from this pit, through chutes leading to a tunnel below, on to a belt conveyor and is elevated to a cylinderical steel coke bin of 750 tons capacity. SINTERING PLANT Practically all of the fine material treated at the lead plant, such as concentrates, con-centrates, flue dust, etc., requires sintering sin-tering to agglomerate it before including includ-ing it in the charge for the blast furnace. fur-nace. The various materials for the charge for the sintering plant are drawn from the bins by mechanical i feeders adjusted to deliver the desired portion of each to a belt conveyor j which discharges them to a mixing j device. From this they fall on an i inclined conveyor belt leading to the feed floor of the sintering plant where the charge is distributed to the five ton feed hopper above each machine. There are ten standard Dwight-Llovd Dwight-Llovd sintering machines. 42x26-1 inches inch-es The charge is mechanically spread ' in a thick layer on a traveling grate.! The surface of the charge is ignited : by passing under an oil burner. Ig- , inition is maintained by the contmu-1 ous drawing of air through the ignited ignit-ed bed by means of suction boxes connected con-nected to a suction fan. Sulphur is about 12 per cent in the charge and is roasted down to about 3.0 per cent in the sinter. The material fuses slightly and forms a clinker-like mass which is discharged at the end of the machine and falls into railroad cars. These cars are hauled to the blast furnace bins and the sinter dumped therein to form part of the charge to the blast furnace. Each sinter machine has a capacity of 200 tons of feed per 24 hours. Fuel used is gas oil of about 36 Beaume. The gases from the sintering plant are passed through a Cottrell precipitation pre-cipitation plant' where much of the dust they contain is deposited. The gases pass through a flue to a brick stack 18 feet in diameter and 200 feet in height. The Cottrell dust is either return ed to the sinter plant or sent to the arsenic plant, dependent upon its arsenic ar-senic content. BLAST FURNACE PLANT This plant consists of five lead blast furnaces 52 to 55x180 inches at the tuyere line. Each furnace has 25 tuyeres. tuy-eres. The height from tuyere line to cnarge iioor is Z4 ieet 8 mcnes. ine capacity of each of these furnaces is about 2G0 tons total charge per 24 hours. The charge cars have hopper bottoms bot-toms with hinged drop doors, and are electrically operated. They are of the same length as the blast furnace. The bins are fitted with suspended weighing hoppers. The constituent materials of a charge are drawn into these hoppers, weighed, and dropped into the charge car, while in motion, thus bedding the charge in the car itself. it-self. The car is run over the furnace and the charge dropped therein. The gases from the blast furnace are drawn off just below the charge floor and enter a cylinderical dust catcher, tangentially. These catchers are 20 feet in diameter and 18 feet in height. The gases are discharged trom this catcher into a steel balloon flue 498 feet long, whence they are forced into the baghouse by a Sirocco fan with a capacity of 180,000 cubic feet per minute. This brick baghouse contains 1440 cylinderical cloth bags 18 inches in diameter and 30 feet in length. The fumes from the gas is shaken from the inside of the bags by reversal of the pressure on the bag, causing it to collapse. The fume falls into pits from which it is removed periodically and returned to the blast furnace as part of fresh charge. The filtered gases from the bag-house bag-house are discharged through a steel downtake to the same stack into which the sintering plant gases are received. Slag and matte are tapped from the blast furnaces into large movable forehearths in which separation is made by gravity. The matte is tapped from the settler into 3-ton pots and hauled to the converting plant. The slag overflows from the forehearths into a second settler and from that into a 7-ton slag pot in which it is taken to the slag dump. Lead is tapped from the blast furnace fur-nace into three cubic foot conical pots and taken to the drossing plant. DROSSING PLANT The drossing plant contains four cast iron kettles each having a capacity capa-city of 30 tons of lead. They are coal fired. The pots of lead received from the blast furnace are poured into these kettles. The molten lead is cooled and stirred by means of compressed com-pressed air which causes the impurities impuri-ties (mainly copper) to collect as a dross on the surface of the bath. This dross is skimmed off, pressed in a Howard press to remove excess lead and returned to the blast furnace charge. COPPER SMELTER All ores for the copper department j are crushed to uniform size and stored ; in steel bins of 2000 tons capacity. From these bins and the concentrate j bins the ore and concentrates re?pec- ! tively are fed through chutes on to ! conveyor belts which elevate these materials to the feed floor of the roaster plant. ROASTER PLANT The plant consists of thirty-two Evans-Klepetko McDougall roasting ing furnaces, each with six hearths sixteen feet in diameter. The capacity capa-city of each furnace is about 50 tons of feed per 24 hours. Each furnace is fed from a cylindrical steel hopper of 10 tons capacity. The ore and concentrates con-centrates are distributed to these feed hoppers by a series of distributing conveyors with traveling automatic trippers traversing the feed floor. The gases from the roasting furnaces fur-naces are conducted by two brick flues to a rectangular steel and brick dust chamber, 120 feet by 140 feet by 40 feet high, where the larger portion of the dust is deposited. The gases pass- from the dust chamber into a flue-type Cottrell precipitation plant, where an electric discharge precipitates precipi-tates the remaining dust, and thence to the copper stack, 25 feet in diameter diame-ter and 350 feet high. The roasted material is discharged from the furnaces into hoppers. From these hoppers the roasted ore, or calcine, cal-cine, is drawn off in small bottom- dunip cars holding four tons. These cars have inverted hopper upper parts which are held tightly in place against the bottom of the hopper by springs, to prevent the heavy loss of calcine by dusting which would otherwise occur. oc-cur. These cars are hauled to the feed floor of the reverberatory furnaces. fur-naces. The dust from the dust chambers cham-bers and that from the McDougall Cottrell treater are also hauled to the reverberatory furnace feed floor. Some furnaces are used for the pre-roasting pre-roasting of lead concentrates, materially materi-ally reducing their sulphur contents, preliminary to their inclusion in the charge to the sintering plant. This calcine is drawn off in standard railway rail-way cars, and thus transferred to the sintering plant ore bins.. Five roasting furnaces are used for the volatilization and condensation of arsenious oxide from smelter by-products. The escaping gases from these roasters are filtered through a small baghouse. The condensed oxide is automatically barreled for shipment. REVERBERATORY FURNACE PLANT This plant consists of three reverberatory rever-beratory furnaces, Anaconda type, each having a width of 19 feet and a length of 102 feet. The feed to the furnace, consisting to a large extent of flotation concentrates, concen-trates, is very fine and is dumped from the cars into main calcine hoppers hop-pers at the bridge end of the furnace. The feed is then distributed to charge holes in the roof. The hot gases leaving the furnaces are passed through five 700 H. P. Stirling water tube boilers. A large part of the heat energy otherwise lost is recovered in the form of steam power. These boilers furnish steam for the entire plant. One boiler is also provided with an automatic underfeed un-derfeed stoker. There are also 350 H. P. boilers, hand fired, in reserve for emergency. The gases, after passing the boilers, boil-ers, enter a brick flue 18x29x1300 feet in length leading to the copper stack into which also the roaster gases are discharged. The charge is fused and the copper with some iron and sulphur combine to form matte which settles to the bottom of the furnace and carries the gold and silver with it. The remainder of the charge forms slag which floats down above the matte. The matte is tripped through cast iron launders into in-to pots in the converter building. The slag is intermittently skimmed at the front of the furnace into slag pots of 227 cubic feet capacity. Slag is haul-'d haul-'d to the dump by electric locomotives. locomo-tives. Each furnace has an approximate capacity of 340 tons per day of charge, with a ra'in of 4 5 CONVERTER PLANT The converter plant is equipped with 5 stands, electrically operated. The converter shells are of the horizontal hori-zontal barrel type, 90x150 inches, and lined with magnesite brick. Two electric traveling cranes handle all material, the one in main converter convert-er aisle being 00 tons capacity and the other, in casting aisle, of oi) tons capacity. Three converter stands are used in blowing copper matte. The gas from these passes through a steel flue to a Cottrell treater, where electrical discharge dis-charge causes deposition of the fume carried in the gas. The gas then passes On to a stack 6x140 feet. The converter stands are used for blowing lead matte from the blast furnace. These are connected by a steel flue with a baghouse, similar to the blast furnace baghouse already described but containing only 960 bags. After filtering these gases pass by a brick downtake to the converter stack, 15 feet in diameter and 150 feet in height. When received from the blast furnace fur-nace the lead matte is poured into these converters and blown without addition of any silicious material. The lead and zinc are volatilized and pass to the baghouse, the fume from which later is returned to the blast turnaces. ihe residue in the converter convert-er contains such copper as was contained con-tained in the lead matte and is transferred trans-ferred to a copper-Wowing converter for recovery of this metal as blister copper. The ladles of copper matte received from the reverberatory furnace are transferred by the crane to the converter con-verter shells. Silicious ore is added and the charge is blown, producing blister copper and slag. The copper is poured into a ladle and cast, in moulds, the slabs of copper weighing about 350 pounds. These are loaded on a truck, weighed and transferred to a railroad car for shipment to the refinery in New Jersey. The slag produced is granulated and transferred to the sintering plant charge bins, where it forms part of new charge. COTTRELL TREATERS Three separate installations arc in operation here. The sinter plant treater, handling all gases from the Dwight-Lloyd sintering sin-tering machines, consists of 4 unils of two 110-pipe sections each. The pipes are 12 inches in diameter by 15 feet in length. The converter treater, handling all gas from converters blowing copper matte, is divided into two sections-(a) sections-(a) regular pipe type, containing 110 pipes similar in size to those in the sinter plant treater, and (b) of box plate type. The McDougall roasting plant treater treat-er treats all gases from the McDougall McDou-gall roasters operating on copper and lead ores It is of flue plate tvpe and consists of two units each 10 feet high 12 feet wide and 61 feet long. This tvne of t.reMor ,i,.i i ..l this plant, has proven of high efficiency effi-ciency and has been adopted by several sev-eral other plants with modifications to suit their conditions GENERAL ,u uC; P"W('r is Purchased from An tV';' 1 "W,'r & Li-'ht company. All I). C. power required is generated in a central power house. In the same building are the blowing blow-ing engines for the converters the blowers for the blast furnar.-s. and i the 10-pound air compressor for gen-icr,-il service. Steam js f,lrT,j:,h,,f hv thr, hllil,r .plant, described in connection with the reverberatory furnace plant. Jhe shops consist of well Cq.lippno! blacksmith, boiler, machine, carpenter carpen-ter and electric shops, with crane service. ser-vice. A completely equipped analytical I liberal ory j s maintained where all control and smelter product analysis are made. All buildings are of steel 0r steel and brick. A safety department is maintained through which safe working conditions condi-tions in the plant are maintained. Ed-( Ed-( Continued on Page 4) smelting and Milling (Continued from Page 1) ucation of men along these lines is lv means of a bulletin and accident tec ord service and also by personal con tact. A resident nurse and first aid hos pital are always available for immedi-ate immedi-ate care of the injured. A small emergency hospital is maintained in Tooele City, for certain cases. ps. tients are conveyed here by m0 ambulance, or where advisable to Salt Lake City hospitals. ' Well equipped change houses, with individual lockers, are provided, tinder care of a janitor. Some idea of the importance of this industry to the community as well as to the mining and smelting industry in general can be formed when it is realized that at the present tins about 900 men are directly employed in connection with the smelting ar.J concentrating operations at the plant, with a monthly payroll of nearly $135,000.00, and in addition several hundred more are indirectly employed in the mining of ores and the necessary neces-sary fuel and fluxes used in the smelting operations, as well as in the refining of products from the smelting smelt-ing operations. During the year just past nearly 700,000 tons of ore were handled at the plant in addition to nearly 85,000 tons of fuel and over 50,000 tons of limerock. The production produc-tion of copper bullion amounted to considerably over 10,000 tons, leal bullion production was about 60,wj tons, and nearly 50,000 tons of z:;t concentrates were produced for the treatment of the Great Falls plant of the Anaconda Copper Mining company. com-pany. Following out the general policy H the company in maintaining the plat; under the most efficient operating conditions possible, an extensive campaign cam-paign of improvement has been inaugurated in-augurated and new construction wri of several hundred' thousand dollars valuation is being undertaken at the present time. Owing to the greatly increased activities of the company during the past three or four year-, as well as other increases in the mining min-ing and milling activities in the immediate im-mediate district, the housing situation in -Tooele has been rather unsatisfactory. unsatisfac-tory. With the idea in view of alleviating alle-viating this situation and also in order to benefit as much as possible their employes, the company, through the International Building association, b instituting an extensive house bailing bail-ing campaign and expects during toe present summer to have erected aboi fifteen cottages. These cottages rA be built under the supervision of tk Building association on plans selected select-ed bv the employes for whom they will be built, and will be sold on i plan which is very attractive to to; employes. |