Document re1oNXg0vQGqr6xwKVVZKaz7V

0 p T i. w po u t m mmm k mmm INCORPORATED Wilmington, Delaware SLA.rnouX > n ri.A*Hagetm - P^Gedd Newark J.Jackson - Newark L * B .Magruder, Jr*. Newark II#A Christian R.B.Baldwin J.C.Xawranca r C.i,Ivans B.S.Mdler lag* Dept* File Hovember 15, 1951 Q. ft. CAHTHStL mPUmNTmMANAGER AltfBRRAtB SOORGES OF LBA'D - 23,^49 VISIT TO LEAD SMELTER IIS HBFXIS1I OF THE BEES SMELTING AID IEFIHXIG COMPART BI SB PORT PIRSOIMEL Through arramg@meata.mde by .Mr* G, R. Cantwell, the writer and Messrs* E* Gadd and 3* Jackson oT Newark, visited on Novembar 10, 1951, the Bare Smelting and Refining Company secondaries lead smelter and refinery located at Ashland and lewis Streets, Philadelphia, Pennsylvania, where we were met by Mr., Julian Bars, President of the subject company# The purpose of the visit was to discuss with Hr* Bars the nature of tjbe raw materials used, and the products mad in the refinery, and to see the metallurgical operations employed at the smelter and refinery with a view of coming to a fuller mutual understanding- of how to best prepare and subsequently utilise the Bars Company lead flue dust as a substi tute for metallic lead at the Pigments Department plant in Newark, 8. J. Extreme caution was exercised during the visit against any discussion in detail of the du Pont .Company5 process in Newark, and likewise of it items of "know-how belonging to the Bars Company9 operations, ISffiABSfS^ Preliminary discussions held in Hr* Bern office with Mr. Bars and the du Pont personnel included a statement of the purpose of the visit, and how certain impurities as sulphur, chlorine, iron ndccopper are partic ularly .deleterious to the Newark operations* Mr* Bsrs suggested at the outset that an immediate trip through the refinery to see the equipment, raw .materials used, and products made would expedite the visit. The smelting and refining equipment consists of! three lead blast furnaces (two of which were in operation}? two reverberatory furnaces (one of which was in operation)? drossing kettles, a Mace sintering machine (not in operation)? and storage facilities for raw materials used and products made. An extensive flue dust collection system using cyclone scrubber was seen, and it was pointed out that the scrubbed, wet flue dusts from the reverberatory furnaces were collected in a sump apart from the 6, R,' Cantwell ~2-*> Movamber 15, 1951 scrubbed, wet flue duets rm the blast furnaces, which are collected in another Snap* Importance mu attached to the feature of the separate romps* since the sludges deposited separately are excavated by a ciam-ahell type bucket and stored on one common pile where they a allowed to dry by natural drainage, It is thought that the dusts from the reverberatory ^furnaces comprise 35$ of the weight of total dusts produced {remaining 65$ originating from the blast furnaces), and are lower in impurities than those from, the blast furnaces, it was pointed out that raw material of high chlorine content {as T.E.L. residues from the Chambers Works) are given a water leaching and washing operation to extract chloride salts, and then fed to the blast furnaces, this means that high chloride content flue dusts originate from the blast furnaces. It is estimated that approximately 200 tons of flue dust are produced .monthly {confirmed by telephone with Mr., Bars), A large pile of com blued flue dusts was seen in the storage area sad probably contains in the order of 500 tons of material. Bay Material large piles of scrap storage batteries were seen and examined. This material is a considerable source of sulphur in the fora of PbS04 from the decomposition of the cells., residual sulphuric acid present, and other adhering resinous, organic matter,. Other materials pointed out were lead drosses fin the form of large buttons), and residues from the T,E,1. operations from the Chambers forks. This X1.1aymateriaX is a considerable source of chlorine .as received, and is therefore leached and washed with water to remove as much water soluble salts as possible* and after draining forms -a part of the charge to the blast furnaces. Mr. Bers pointed out that it ia absolutely necessary for his blast fur nace operations to remove as much Had as possible by leaching and washing., since MaCL has a relatively low melting point {600G, ) and may run down through the charge, cooling it, with subsequent danger of freezing the charge.* Another harmful characteristic of chlorides in lead smelting is that they increase lead losses due to volatilization. It is significant of note that no lead minerals nor concentrates are smelted at the refinery, Mr, Bers stated that this fact is due in part to the lack of sintering equipment (one sintering machine .available), which he might .expand in the future. Universal adaptation of flotation concentration to lead ores with extreme fineness of the concentrates entails sintering as a "mast" for blast furnace smelting of concentrates. Smelting Operations The reverberatory furnaces and blast furnaces supplement each other in operation as far as possible. It was indicated that the materials charged to the reverberatory furnaces contain less impurities than those charged to the blast furnace and which is borne out by the fact that less impurities {Fe* 0u,, Cl) are expected {samples are being pre pared) to be found in the flue dusts from the reverberatories, The reverberatory operation appears to be essentially one of melting.{with intermittent oxidation and reduction) and was explained to be a 24-hour cycle yielding 25 tons of lead per reverberatory. The other products DUP050068748 6, R Cantwell 3* November 15# 19.51 from the reverberatory smslting .are a slag containing essentially oxides, sulphides* sulphates and silicates of lead, and this slag is .crushed and smelted in the blast furnace. The fins dust produced con sists mainly of oxidised expounds of fins particle Bim dm to the high temperature of the reverberatory .gases of th order' of 2500F* flit blast funsace operetion consists essentially of reducing the lead to metal I bullion) and slagging the impurities to separate the from th ffittal by differences in specific gravity* Thus to the load raw mattrials charged to the furnace, there is added cote and limestone, and the products from the furnace art slag, matte, spedas, bullion and .flue dust. When the slag contains over 2% lead, it is, crushed and re turned to the furnace. 'Mr* Bert stated that the matt and spei.ee art shipped to be refined elsewhere. The metallic lead is transferred-to dressing kettles for refining* The impurities held in solution or suspension in the crude lead are removed in the dressing kettle's by an operation known .as Crossing" or oxidation by mechanical stirring of the molten lead and addition of compressed sir or steam, and by th addition of sulphur* The impurities, such as antimony, arsenic, iron, sine, and copper are slowly oxidised and rise to th surface as . dross which is skimmed off the surface by, a perforated spoon. Copper my b removed s a sulphide by the addition of sulphur (brimstone) as a dressing reagent* Th .drosses ar usually returned to the blast-furnace charge, or my also be smelted aepartely in a reverberatory furnace. mmmL. The flu '.dust fro the Bare Company reverberator! .appears to he a more attractive alternate source of lead to supplement metallic .lead for the lead nitrate and TB*1 operations because of expected lower im purities content. Therefore, it was requested of Mr. Bers that special samples be takes, of the reverberatory flu dusts on an nas is"' basis* That is, the scrubbed, wet dusts will be sampled as they go for collection to a settling sump, and will be shipped to Hewark as a slurry, as it is desired that no drying operation b performed on* the staple by the Bers Company. Mr* Bers stated that a source of equal material .(reverberatory flue dust, same tonnage) is being produced and could probably be obtained from a lead refinery in Boston, and. in which Mr* Bers .has a part interest* Mr* Bars thought he could obtain for sale to'the du Pont Company from a source outside of his company operations (source not named) a lead dross containing 45-70# lead, with a voluminous amount of coal content (small percentage on weight basis), with appreciable iron content but free from chlorine and copper* Mr* Bers did not have information as to tonnages of this dross available, but he would be glad to get this information and other pertinent data if requested of him* DUP050068749 GU S Cantwell November 15 s 1951 As the flue dusts (reverbarat ory and blast furnace) are collected in separate stamps for settlings they could be stored for drainage on separate piles and shipped separately* rather than, on a common pile mb at present, Mr, Bars stated that his sintering machine {lace} was not in use due to man-power .shortages, and economic factors involved. Pig lead ingots from Bars Company are sold under the name BSCHUTXXLXn* "Corroding lead" is used in the trade to describe the type of lead re fined to a high degree of purity (99.94$ minimum), and for many oper ations requiring pig lead, "corroding lead" purity is not necessary (there are six other common commercial grades of pig lead). In the manufacture of storage-battery grids, an alloy of 94$ lead and 6$ antimony is used, and in some new developments with storage batteries, lead is alloyed with silver and arsenic. ENGINEERING SERVICE DIVISION ENR:vm B. SL Roberts DUP050068750