The material to be treated is a zinc ore from Boone County, Arkansas, a district as yet but little developed but from present indications of the ore deposits found in the vicinity, it promises in time to become one of the most important zinc producing districts of the United States --page 1

Conrads, Ralph Augustus

Quinn, Matthew Vincent

English

Missouri University of Science and Technology (Missouri S&T): Scholars' Mine

Scholars' Mine Bachelors Theses Student Theses and Dissertations 1904 Design of a mill for the concentration of an Arkansas zinc ore Ralph Augustus Conrads Matthew Vincent Quinn Follow this and additional works at: https://scholarsmine.mst.edu/bachelors_theses  Part of the Mining Engineering Commons Department: Mining and Nuclear Engineering Recommended Citation Conrads, Ralph Augustus and Quinn, Matthew Vincent, "Design of a mill for the concentration of an Arkansas zinc ore" (1904). Bachelors Theses. 235. https://scholarsmine.mst.edu/bachelors_theses/235 This Thesis - Open Access is brought to you for free and open access by Scholars' Mine. It has been accepted for inclusion in Bachelors Theses by an authorized administrator of Scholars' Mine. This work is protected by U. S. Copyright Law. Unauthorized use including reproduction for redistribution requires the permission of the copyright holder. For more information, please contact scholarsmine@mst.edu. F01, THE.INSUBJECT~llDe~jgn of a Min fot" the Concentration of en Arl\an~as Zinc Ore. HR. A. CONRADS. 1'.11. V. QU!NN.Des1!n of a MIll tor the Coneentration of anArkansas Zin. Ore.The material to be treated is a zine ore from Boone County,Arkansas,a district as yet but little developed but from presentind1eationa of the ore deposits found in the vieinity,it promisesin time to beoome one or the most important zine producing distr1¢ofnthe United states.An abund.ant water' and tj.mber supply makes the cOst orere.tion and operation of the mill comparatively cheap.One or the greatest drawbaeks to the development or thedistrict in the past has been the la8k of railroad facilities butthe V.~1te River branch of the ~lissour1 Pae1fie Railroad,whieh isnearing completion,overcomes this d iffieul ty,m aking the dist"'1cteasily accessible and putting it on a direct line to the market.The water supply is of especial importanoe as it does awaywith the necessity or savin! the water from the mill.Analysis of Ore.The ore,as earefully sampled in prospeet working consistsof an average or nine per.ant zinc blende in a !angue or Iraylimestone with a. small amount of dolomi te and a traee of' ironpyrite.Oeeuranee or Ore.rines (material passing a 24 m.m. ring)Cap~eity 0 f Mill.and roof of corrugated iron.2Laboratory Tests on the Ore and Conelusionsdrawn trom them.In the Missouri d1str1et the present practi.e allows fromtwenty to twenty five percent of the zinc in the ore t6 !O towaste in the tailings. We propose to reduee this loss by a morecareful and better treatment or the slimes which under the Ir 8 Nva11ing Missouri practice is almost totally neglected.Experiments were carried on to ascertain the best me~ods ~or crushing and concentrating the ore. From these experiments themoat eeonom1eal size to which the are should be crushed was de-termined to be twelve m.m. Piner crushing than this tended to maketoo large a percenta£e or slimes. Crushing to this size ~ivesabout ten percent or middlings but also gives a large enough oon-eentrate for the first st~e.or erushing. ~he middlings werecrushed through rolls set close and screened through two and one-half m.m. sieve and together with the same sized material from thefirst erushin~ were treated in a classifier. The spigot dischargefrom this elassifier{eons1sting of 2 1/2 m.m. to 1 m.m. material)was treated in a fine jig.The system of classifiers used in our experiments andsuperiority in the rol1ow1n~ respects:" ,I, ',J,I/ J j.1 J I, JJ , J 'J I, J I) ') ~,'J J } ) 1 ) ) .'] ~: 1 'J 1 'J ~(.) ne11v er ing the classified material. to the table~J;~Without )'iLn" )'JJJ JI J ) )exce~3B of water, thus effe8ting a h1!her saving t~t)1n tm(a) Simplicity and consequently tew repa1rs,ete.(b) Easy relulationwhich will be installed in the mill is the Sherman System. Although) ,'I'"),thl's system is new and has not been used in Missouri to':'J~~r")'.) "IJ ., )knowledle,it has been used in mills in the west and has:povon,,1t~,I J J~;f J ,):.' ) ,) )) J j)J j )if.J,·, ..j J , ~ J J , J J J './ I' JJ J ) ; ~ / :, ',:,':-',', }J))'.') I""J " /, I, ,.J J J J ) I ' J J ~'lJ J J, J )"'"fine material.3B1 the use of this system in oonneetion with the W11fleyTables,8 greater percentage of the value in the finea and slimeswill be saved and also a higher !rade eoneentrate obtained wit hpoorer tailings wastedPlow of the Ore through the Mill(subjeet to change in detail)The ore is brought to the mill in cars and 1s dumped ontoa grizzle,. with bars Bet twenty four m.m. apart. A powerful magnet1s plaeed at the upper end otthe IZ1zz1ey to remove any pieces ofiron,piea8s of friek,drills,hammers,ete.·whioh may be brought fromthe mine and would be injurious to the crusher and rOlls.':'he material passing over the grizzley goes into a bin and isted through a shute to Two Blake Crushers set to twenty four m.m.From the erusher it drops direetly into a bin together withthe material which passes through the grizzley. From the bin it isfed by a roll feeder to one set of Rolla set to ten m.m. Prom therolla through a chute to an elevator delivering the ore to atrummel with twelve m.m. round holes. The oversize is retur.ned tothe bin and ia recrushed,undersize goes to seeond trummel havingsix m.m. round holes. Oversize goes to two .oarse Harz Ji~B,under­size to third trammel with two and one half m.m. square hOl,~,~.Oversize to three Harz J1,;s. )liddlings from first rive j1~,~",io...,'I,llt~ether with second, third and fourth hutch product or 5~~:O:':j~"~',:',an,,~i.,hutches ot jigs number' six, 88ven and eight are recrUBh~,~"$',',on :':"':','"middling rolls and pumped by centrifugal pump to thi~d; tr~el,."Undersize from this trammel to ri rat elassifier, SP1got':',:'~"s~~,rging',',::,' "'" )'"to three fine ji!B,OVerflow to second classifier with B~tiot d1s-.harging to one W11fley Table. Overflow from second elas~ff1ergoes to third classifier with spi!ot diseharging to One Wllfleytable.4Overflow from third goes to fourth elassifier with spigot d1sehar~to one Wilfley ~able. Overflow from fourth elassifier to waste.Spee1fieat1ons of Ma8hinery Employed in the Mill.1 Gr1zz1ey 6' X 10' bars 24 ~I.M. apart. Slope 45.2 No.5 Blake Crushers, 15" X 9", teed set to 24 m.m.1 Set Middling Rolls, set closeI Set No.1 Rolls 14" X 36" set to 12 ~I.M.1 Roll leader1 Trommel 4 1 X 7 1/2' t 12 m.m. round holes. Inel. 5 degrees.17 revolutions per minute1 Trammel 2 1/2' X 5', 6 m.m. round holes, inel. 5 degrees,17 revolutions per minute1 Trammel 3 1/21 X 5', 2 1/2 m.m. square holes I nel. 5 deg.17 revolutions per minute.1 Elavator2 4 Com. Harz J1ss 7 sq. ft. area waeh screen3 4Com. Harz Jigs, 3.5 sq.ft. area each screen3 4 Harz Com. J1~s 3.5 sq. ft. area aaeh a.reen.3 W11fley Tables.1 Sherman Classifier 4'3" X 12'1 Sh9rman Classifier 6t Ow X 12'1 Sherman Classifier i'6" X 12'1 Sherman Classifier 12'0" X 12'" 10-" 5"" 1"" 1"" 1"" S"" 3""1.5HP" 1""1""1 "1.5"--HI'but it would bett""""""75506625.297 1/2" "63"""""W11tley Table (.oarse)(medium)(tine)2 Blake Crushers1 Set Rolls1 Set Rolls(m1dd11n!)1 Trommel1 "1"2 -4 Com. Harz Jiss3 ..4"-"3 .4" " "15Capaeity and Horse Power Required by Maehinery.Capae1t)' 80 ton silO hours 24IIP"120 ""25 "" 120 "1 EJlevatorCentrifugal Pumps,One 12t One #6,OneTotalThis gives an actual needed HP orwell to allow 100 HP which would amply co.er losses in rriction,transm1ssion,ete.One one hundred horse power O••lies Engine,One one hundredhorse power Heine Water Tube Boiler. Heine boilers are to beemployed becRuse ot their 8rri.1en~y,greater satety and longerlife.A teed pump and pump(#6 Centriru~a1 Pump) tor mill supply.The diameter of shafting to be used was determined by formula81v.n~_in Kentt. Me.bani.al Ensineers PO.kat-Book.J)n Dlam of shatt in in.hesH HP to be transmittedR number or revolutions per minute.,The width of belting neeessary was determined by formula tromKent'sW widtb or belt in in.hesR revolutions per minuteL leni'. of are or contact in teetd diam or pulleya angle or are or eontaet.Corliss mng1ne 90 revolutions per minuteDiameter ot fly wheel 10 feet" or shaft 4 1/2"To run main shatt at 120 revolutions per minute120 : 90 120: X 90" 7 1/2 feet diameterpulley on shart.Shaft Making 120 revolutions per minute.Maeh1ne Speed Required Pulley Maeh. Pulley onSh.artBlake CrusherRolla~.-rnT1/rrLt-l.'J I Yz.vn. )!toll. ol11ower~~l~~arJ'i~B #: 1 & 2" 3,4 &5" 6/7 &8Tables by bevelsBar trom mainshaft.)1'0. 2 Cent .PumpNo.6 Oent. Pump250 rev.per m.120 " " "17" " "144" " "190 .." "200 I " "240 rev. P" min850" " "745" " "24" diam7a" "Ratio of bevels3:2018"Ii"16"RatiO or bevel2:16"16"50"78 "21.'28'.530" ,42.5"

Design of a mill for the concentration of an Arkansas zinc ore

https://scholarsmine.mst.edu/cgi/viewcontent.cgi?article=1266&amp;context=bachelors_theses

Design of a mill for the concentration of an Arkansas zinc ore

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