Show A description of the united states smelter THE concentrating department when the ores of the old jordan and the galena mines of bingham the property or the united states smelting smelling Sm elting company began to show the presence of zinc in such quantities as to seriously interfere with their treatment in the companas comp anys lead furnaces at the midvale smelter the company with the ahe same spirit with which it attacked the pr problem ob presented by the smelter gases set to work to find a way by which the zinc might be made not only unobjectionable but a source of revenue as well the actual separation of the zinc into a commercial product is not within the province of this article as the plant employed is worthy of separate consideration which will deal with the process by which the ore is prepared for the further re treatment and also with th the e preparation of the concentrates for the lead smelter the mill employed has always been considered by the mill nien men who have been caba capacity city for a full days run from this bin the ore is fed by a plunger feeder to a nine by fifteen inch blake crusher of allis chalmers make which breaks il ii to pieces not exceeding one inch in diameter before passing to the crusher the crude ore is run over a three quarter inch grizzly which takes out the tines lines the crushed product with these fines goes to the number of water is run in on one side of the partition until the trough tips from the weight when the water spills out and the trough fills on the other side the crushed product from the rolls goes back to the number one elevator to be elevated again and passed through the first from the fine ore bins from the fine ore bin the crushed ore is fed to the number X Z 1 L F g LF ot 7 j 4 W photo hj by lerv A 1 I palmer concentrator U S smelter familiar with it as a very efficient type of concentrating mill and since the installation of the additional machinery for the treatment of the lead iron zine zinc concentrates it has proved doubly interesting the plant which has a daily capacity of tons is situated near thu the smelter and convenient to the denver and rio grande railroad over which the ore is hauled in 45 ton hopper bottom cars these are dumped to the receiving bin in which has d a one elevator which raises it to a three by six foot with three quarter inch punched holes the oversize from this goes to a set of allis chalmers rolls and the undersize to the crushed ore bin before passing to the bin the undersize is sampled by means of a spout which is swung across the stream of ore sit at intervals ter vals by means of the tipping of a trough this trough is hung in the middle middie and is divided by a partition A stream two elevator by means of a plunger feeder and is raised to the twin as they are locally called they are a pair of each three by six feet with punched screens the oversize of these is to a set of allis chalmers rolls which return their product to the number two elevator the undersize from the first goes through a series of three other these with wire screens whose free openings run from one fourth to one six inch the oversize of each goes to a three compartment jig of the typical hartz type with sherman plungers these plungers the design of mr F W sherman superintendent of the daly daiy west mill at park city are distinguished by stout steel straps bracing the plunger proper to the eccentric stem and by having the plungers bound with rubber coasto so as to make the water compartment nearly airtight air tight and thus give increased suction three of these jigs treat the oversize from the three the undersize from the last goes to a sizer which feeds two more jigs thus all of the ore receives at least a preliminary treatment on the jigs which is a very wise method as jigging is an inexpensive method of concentration and the process takes out a certain amount of the ore which makes a consequent saving in re crushing and tabling high grade lead concentrate all of these jigs make high grade lead concentrate on all three compartments and no side discharges are employed except on the numbers two and three and here they are not used in the usual way but merely as a de watering device for the tailings the tailings are discharged through the side gates and the water runs to waste over the tailboard the tailings of jigs one two and three go to a shaking launder which discharges to a de watering wheel this launder is suspended and is driven at the rate of shakes per minute by an ordinary ec number three elevator the undersize of the goes to a series of five double cone classifiers of the latest model made by the colorado iron works the cone classifier has not found great favor in this section of the country where the preference seems to be for those of the calumet end and spitz kasten type there is no part particular cliar reason for this as lne ine cone classifier is very satisfactory and can be very closely adjusted the adjustment being effected by the water or by shifting the inner cone or in the new type by means of a button between the points of the cones jigs tables and SI Gl imers the first two classifiers send their spigot product to the number five jig which makes a good concentrate on the first hutch and a middling product on the second and third hutches this middling product is retreated on a wilfley table which makes some good lead concentrate a good zinc concentrate z 4 sea pa 4 ap saw bov interior of power house U S smelter photo ty if lera A palmer centric instead of using the differential motion usually employed it has given excellent satisfaction and does not cause the trouble experienced with many shaking launders the watering de wheel which is the make of the allis chalmers company is a wheel thirty inches in diameter set in a box against a side which has an angle of thirty degrees the wheel is provided with bent scrapers around the edge so that as the tailings from the jigs fall into the box from the shaking launder they up the side and over the edge the water which comes to the box with the tailings overflows to a sizer which sends its spigot product to the number three elevator and the overflow to the tailrace the number three elevator discharges to a pair of which cut out all which will not pass a ten mesh screen and sends it for re grinding to a set of ten by seventeen nevell rolls whose product goes back raj to the and heavy each of the last three classifiers feeds an table and the overflow of the last goes to a series of sherman classifying tanks varying in diameter from three and one half to seven and one half feet the overflow of the last of these tanks goes to a series of twelve small se etling tanks each three and one half by five feet each two of which feeds a sherman slimer while the tab table le is not as well known as the wilfley it is an excellent concentrating machine and is giving very good satisfaction here its strong point is in the lack of repairs necessary it being free of all complicated parts the sherman slimer is made on the principle of the wilfley slimer but with a very different head motion the tables make four products concentrates talf tailings ings and slimes and the sherman slim ers only concentrates and slimes all tailings from these tables are rejected the two number four jigs those that are fed from the bizor send their tailings to a sizer whose spigot dt discharge goes to the number three elevator and from it to the ten mesh and whose overflow runs to the slime department the number five jig the one receiving its feed from the first two cone classifiers sends its tailings to a sizer whose overflow goes to the tall tail race and whose spigot discharge goes to the number four elevator the table and slimer concentrates are all caught in hutches and shoveled into tram cars in which they are pushed outside to the railway spur and dumped directly into the cars in which they are hauled to the smelter the overflow of the hutches and cars runs to a series of five sumps bumps in which it settles and is shoveled but once a month this handling of concentrates by manual labor is to be done away with when the system now being constructed is in operation all concentrates will run by gravity to the boot of an elevator which will raise them to such a height that they will flow to a bin outside this bin is rendered watertight around the gates by rubber gaskets against which the gate is tightened by a cam the concentrates will be drained in these bins and unloaded directly into railway cars the tables which retreat the and slimes are on the floor below the main table floor so that they may receive their feed by gravity the from the ten tables are retreated on six number five wilfley tables on this floor the first four Wilf leys take their feed from the first four Over stroms the fifth wilfley from the next two Over stroms and the last wilfley from the last four Over stroms the feed is all classified before going to the first tables and as it runs directly from them to the middling tables no classification for the latter is necessary the middling tables make a lead concentrate a zinc concentrate zinc iron lead and tailings the lead is shipped the zinc goes to the zinc mill the go to the number three elevator and the process described is repeated and the tailings are rejected the slime from the tables goes to a centrifugal pump which raises it to a settling tank the spigot discharge of which goes to the classi tying tanks which feed the tables and the overflow to the first of the slime settling tanks the first two middling tables and the table that treats the of the number five jig send their tailings and to the number four elevator the others send their to the number three elevator concentrates for zinc mill this completes the mill as far as it is applied to the making of a product for the lead furnaces for which purpose it was originally constructed there has been installed however a considerable amount of machinery for the making of the concentrates suitable for in the zinc mill which present some features of interest the predominating metals in the ore ot 01 the old jordan and galena are lead iron and zinc any millman knows that the separation of iron and zinc by purely mechanical means is practically impossible without the very closest sizing and much care in the treatment and that even in this case the recovery is only indifferent the separation of these two metals from the lead is not a difficult task and the further separation of the zinc on the electrolytic machines is a demonstrated success so the newer portion of the mill was equipped with machinery to further work the of the older portion making a concentrate in which the zinc would be found with about twenty five per cent of the iron and only such small quantities of lead as it would not be practical to attempt to eliminate by concentration the number four elevator discharges to a de watering wheel similar to the one already described and the de watered ore goes to a bin and the overflow of the box to a callow tank the de watered pulp is fed from the bin by a plunger feuder feeder to a five by fourteen foot denver engineering works tube mill which grinds to a forty forts mesh the use of the tube mill for grinding re instead of passing them through a huntington or chilian mill is original with this plant as heretofore the tube mill has been considered a as s a sliming machine pure and simple in this case ic is doing more satisfactory work than either of the other types of mills mentioned and is using less power to operate it repairs are reduced to a minimum as the machine is nothing but a huge steel cylinder with a removable silex lining in which the ore is ground by flint pebbles about the size of a cobblestone cobble stone As the pebbles wear down rr more ore are thrown in and about once in nine months it is necessary to renew the lining aside from this however the item of maintenance is a very small one the ground ore is elevated by two frenier pumps each with a lift of twenty feet and discharged to a settling tank the settlings from this tank go to a R richards ach classifier with five compartments instead of settling against a current of water as in the older types of hydraulic classifier the ore in the richards is forced upwards by the action of a pulsating current of water the result is that the finer sizes are forced up to the discharge open ingin ing in the first compartment and the coarser sizes resist the action of the current and pass on to the next each compartment thus discharging a coarser size than the one pre ous and there being no overflow the first compartment of the classifier feeds an table and each succeeding compartment Part ment a number five wilfley table the callow tank sends its spigot discharge to the feed ed for the tube mill and wa c Us its overflow the overflow of the box that feeds the richards classifier goes to a callow tank whose spigot discharge goes to a sherman slimer and whose overflow Is wasted the slimes from the tables go to the first frenier pump are elevated and eventually go to the slimer the tailings from the tables are rejected the concentrates go to the zinc mill and the to the middling floor where they are retreated on two number five wilfley tables the from these tables are returned to the number four elevator and again go through the process just described the mill is driven by electricity which is generated by a continuous current generator in the power house the continuous current misused is used to avoid the necessity of transforming for the line to the mill the water is taken from the jordan and brought to the plant in a canal seven and one halt half miles long A plentiful supply is assured for all time without reusing any summing up the mill while it does not compare in size with the monster plants that have been built to treat the low grade country rock deposits of copper is a model plant of its kind A high extraction is made with a low consumption of power all portions are convenient and accessible and there are many laborsaving labor saving devices such as are appreciated by the men who have to work with them all in all it is a plant from which one seeking for information or suggestions could get many valuable pointers LEROY A PALMER salt lake city editorial note further description of the united states smelting smelling sm elting plant will be given in two more articles to follow |