US1859781A - Apparatus for treating liquid with alpha gas - Google Patents

Description

May 24, 1932.

F. w. MACLENNAN APPARATUS FOR TREATING LIQUID WITH A GAS Filed July 15, 1930 2 Sheets-Sheet l INVENTOR Fmnh' lfl'Mwclennan BY W M ATTORNEYS y 24, 1932- F. w. MACLENNAN 1,859,781

APPARATUS FOR TREATING LIQUID WITH A GAS Filed July 15, 1930 2 Sheets-Sheet 2 I. I I I I, ll Ell I I I I I llinfin nv. i=1? INVENTOR e I ATTORNEYS Patented May 24, 1932 UNITED STATES PATENT-OFFICE,

FRANK W. MACLENNAN, OF MIAMI, ARIZONA APPARATUS FOR TREATING LIQUID WITH-A GAS Application filed July 15, 1930. Serial N'o. 468,015.

My invention relatesto improvements in apparatus for treating liquidwith a gas and more particularly to an improved apparatus for the concentration of ores by what is commonly known as the flotation process, in which the ores'or other substances are subjected'to aeration in .an aqueous separating medium in'the presence of suitable agents forthe formation of a froth containing valuable portions of said ores or other substances, and thereby separating said values from the barren or rocky constituents thereof.

More particularly the present invent on relates to an improved means for regulatingand controlling the air introduced into flotation machines of the cascadeftype.

The principle of operation and novel features of the invention'will be understood from the following description, taken in conjunction with the accompanying drawings, in which similar reference characters refer to similar parts throughoutthe several views.-

Fig. 1 is'a longitudinal sectional elevation in-exaggerated proportion of the flotation cell taken on line 11 of Fig. 2.

Fig.2 is a transverse section of the flotation cell taken on line 22 of Fig; l. V

Fig. 3 is a section in detail of the air inlet means. p

F ig.4 is a fragmentary section on line 4-4 ofF1g.3. a

Fig. 5 is a fragmentary section on line 55 v The drawings illustrate one type of cascade flotation machine equipped with the improvedlmeans for-regulating and controlling theintroduction of air, embodying my in vention. Air under pressure enters themachine through the headers 10, and passes through the primary airslots 12; These primary air slots v 12 outlet into a central air chamber 14 running the entire length of the. cell. The cross sectional area of these primary air slots is such that they have capacity for carrying several times the total quantity of air required for the operation of the machine, thereby insuring @that suflicient air is always being supplied to the central air chamher to minimize any local fluctuations in air pressure occasionedby varying the size of the discharge openings to be presently described outletting from such chamber to the pulp body. Openings 16, of suitable size and at suitable intervals, are provided at the top of the air chamber 14. After passing through these openings 16 the air finally exits between the flexible rubber strips 20 into the apparatus at the base of the air-lift chamber 18. h The sliding valves 22 are also provided with openings 16a. These valves 22 are seated in position against the inside of the top of the air chamber 14 by means of springs 24, which are secured to the cell bottom at 26. These springs 24 have the effect of providing a flexible base on which the sliding valves 22 slide and at the same time prevent an accumulation of dirt under them and keep the valves 22 snuglyseatedagainst the openings 16 inthe top of the air chamber 14. 1

Along each side of the air chamber 14 are secured the strips of pure gum rubber 20 which come together at the top, as shown at 28. While the machine is operating, these rubber strips 20 are held apart by the air pressure and the air outlets between them in the form of a substantially continuous sheet. When the air is shut off these strips come to gether, making a seal which prevents the pulp from entering the air chamber. The valves 22 which require only a slight movement to open or close the openings 16, are operated by rods 30 attached to the ends of the valves.

The rods 30 pass through stufiing boxes 32 to prevent escape of air and are provided with threads and threaded hand wheels 34 by which means the valves 22 may be conveniently moved horizontally to open or ,closeor adjust the size of the openings 16 with extreme nicety. r

The fragmentary section Fig. 4 shows the valves 22 in three different positions. At 44, the openings 16 are entirely open to the passage of air. .At46, they are half closed and at 48, they are entirely closed. v Partitions 36 are introduced at intervalsin the primary air slots .12 in order tovprevent collapse of the slots and are staggered as shownin Fig. .5.

now in current use, it is important to have separate control of the air volume in diiierent parts of the cell. For example, in arougher cell 100 feet long, it is desirable to use asmaller quantity of air in the first third of the cell Where a high grade concentrate is required and a larger quantity of air in the rest of the cellwhere it is important tomake clean tailings regardless of the grade of the concentrate. In Fig. 1 is shown a longitudinal section of a flotation cell in, which the concentrate is removed separately from three compartments of thecell, as indicated bythe concentric launders 38 and discharge spouts 40. In order to regulate the volume ofair to these three compartments, it is necessary only toi'regula te the air tothet wio end compart ents means of the hand wheelsfi l, after, getting the proper amount of air through the center compartment by regulating, the main valve to the apparatus, aslindicaited at. 42.

i I have found thatthe regulation ofthe: volume 'o fair, entering the flotation cellby the accurate control of size of thefopeninge. through which the air exits directly orsub f stantially directly into the pulp, results in a s teadi erflow of air anda better distribution of air in 'the flotation cell than is. the, case where the'volume ofairto the cell is regulated by valves placed at some distancefrom the ex t openings into the cell.v

I havje als'o found that uniformdistribu tion of air-in theflotation cell is facilitated by providing means for leading I air toffchev zone immediately in front of such openingsin sub-. stantially greater volume than it. caii' be discharged through l such openings and I so in strung a constanthead of airfroin thesprimary source ofair under pressure which the pressureslocally preyailing will notfluctuate,

widely with c hangesjin the size of such air z'iit pf nin the-"pr 636m; invention a be n Ed scribed {with particular? f f l cev to, ,a ,flOfiaf tion, cell operating on: the cascade principle, it 'will be understood that it is capable of.a-p.-.

plication to other types 0: cellsinf vwhich uplift action to be produced. Itwill be fur-. ther understood that various changes in. the details of thelconstructionmaybe madewitlr. out idepart ingfrom the invention, which is not toi be deemed as limited other than as indicated the: appended claims. I

I laim 1 I i 1. Ina-n ore flotation apparatus, an elongated tank adaptedto contain! ore vpulp, a

longitudinally-extending. uplift chamber within 3 said tank, an air chamber, disposed beneath the lower end of ,said upligft chamiher and substantially coterminous as to en th ith Said, uplift hamb jrrme n d pn theupper side, of said air chamber e el -Rin su an ial y n qi shit through which to inject air in an ,upward. ire i nt ru e ee e edJ i h i tank, thereby producing an upward circulation of pulp through said uplift chamber, said means being responsive to changes in the pressure at which air is supplied to said air chamber for opening and closing said slot, and Valve means immediately adjacent to and beneath said slot-forming means for controlling, the volume of; air; supplied through said slot.

2. In an ore flotation apparatus, an elongated: tank; adapmd! to; contain ore pulp, a longitudinally-extending uplift chamber Within said-tank, an-air-chamber disposed beneath the lower end of said uplift chamber and substantially coterminous as to length w h: id. pli t h mber;,. id. ir, h mb e ng-p v dedon i s pp r,s de th-aseries t eles ly pac d. Qn ni sa v lve membe mquntedrinvsaid air chamber, tor; controlling,

e za r; m ghsa nn nings and means di p se mme iat ly. amass. o, and abo Said; Qu ni e f r. definin t ubstantially wn im l t hrou h. h ch to, j c ai i e u -tant alla on uous-sheet n "amp.-

warld' direction into pulp contained within 90.;

l pl di h eugh idi n ings rz pen-r as:

ing and closing sa d slot.

nfil app rabw ot atin liqui w a a a anls nte e ntain quid; a a r c iv ng h mber; spe ed adiacen t el ws r; end o aid a kl ndi n s ant l yt ter?- m nolis. r e sl th ith ai in a dim nsio Of saidnk, .m ans isn sed, .1.1 he uppe ide-0fs idses ec v ngi hamb rr d i ing a substantially, continuous slot, through which to ject gas n. ani pwa td dire t on. 1

into, qu dntai ed ithing a d t i means being, responsive to, changes ;in the a P s re t. i h gas is upn ied tisa d ga receiving chamber'for opening and closing;

aid i ndz alve m anst mm di e y d- 1 0 jacent to and beneath said slotforming, ns, er ltr li J g-r ha volum 0i :gassupplied through said slot.

nfi para us:fer re t n -iliqeidiwi a teas i l; asapeem vqemtaim.- qiiid gass rib tin me n ompri in wees e l s ham er; o i e tj it u aid tank, sa g s-r ce g amber bein pr v d. i h a' series of "closely spaced jopenings for disaea i w 'e qu drava i memben 12 mounted adjacent said openings and"subjstantially coterminous as tolengthf with said series of-fopenings for simultaneously ad justing the e'fiectiye size-ofall of ,the openings in-saidseries, and means disposed '.im-,

mediately. adjacent: tosaid; valve member and. said openings for defining a substantially continuous .slot. thnoughi \which\to inject gas as a substantially continuoussheet into liquid contained 1 within -nsaidqtank saidzs1otrforming means being responsive to changes in the pressure at which gas is supplied through said openings for opening and closing'smd slot.

July, 1930.

FRANK W. MACLENN AN.

Images