CA1144497A - Flotation method and apparatus for recovering crude oil from tar-sand - Google Patents
Flotation method and apparatus for recovering crude oil from tar-sandInfo
- Publication number
- CA1144497A CA1144497A CA000351870A CA351870A CA1144497A CA 1144497 A CA1144497 A CA 1144497A CA 000351870 A CA000351870 A CA 000351870A CA 351870 A CA351870 A CA 351870A CA 1144497 A CA1144497 A CA 1144497A
- Authority
- CA
- Canada
- Prior art keywords
- sand
- water
- vessel
- tar
- oil
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Landscapes
- Micro-Organisms Or Cultivation Processes Thereof (AREA)
Abstract
FLOTATION METHOD AND APPARATUS
FOR RECOVERING CRUDE OIL FROM TAR-SAND
ABSTRACT OF THE DISCLOSURE
This invention relates to an improved method and apparatus for scrubbing crude oil (bitumen) from tar-sands, the apparatus being characterized by a heated vessel for maintaining the tar-sand/water slurry at between approximately 180-200°F., a pair of counterrotating screw conveyors in the bottom of the vessel for agitating the sand and moving it to the discharge end, means for simultaneously diluting and aerating the incoming slurry that produces small bubbles effective to float the crude oil freed from the sand to the surface, an overflow wier running alongside the vessel for catching the oil skimmed off the surface of the water, transversely-extending endless chain-and-flight skimmers for skimmming the oil into the wier, a bottom-opening discharge for the clean sand, and valves controlling the discharge of sand effective to remove the latter without lowering the fluid level in the vessel to a point where the oil previously released can reattach itself to the sand. The method encompasses the steps of submerging the tar-sand in the vessel to a point where the oil previously released can reattach itself to the sand. The method encompasses the steps of submerging the tar-sand in a hot water bath, agitating the sand while thus immersed while continuously bubbling air up through the slurry to float the oil particles freed from the sand grains to the surface, continuously skimming off the oil floating on the water bath from the surface thereof, and withdrawing the clean sand from the bottom of the vessel intermittently and quickly enough to prevent the level of the water bath from falling below the top of the screws.
FOR RECOVERING CRUDE OIL FROM TAR-SAND
ABSTRACT OF THE DISCLOSURE
This invention relates to an improved method and apparatus for scrubbing crude oil (bitumen) from tar-sands, the apparatus being characterized by a heated vessel for maintaining the tar-sand/water slurry at between approximately 180-200°F., a pair of counterrotating screw conveyors in the bottom of the vessel for agitating the sand and moving it to the discharge end, means for simultaneously diluting and aerating the incoming slurry that produces small bubbles effective to float the crude oil freed from the sand to the surface, an overflow wier running alongside the vessel for catching the oil skimmed off the surface of the water, transversely-extending endless chain-and-flight skimmers for skimmming the oil into the wier, a bottom-opening discharge for the clean sand, and valves controlling the discharge of sand effective to remove the latter without lowering the fluid level in the vessel to a point where the oil previously released can reattach itself to the sand. The method encompasses the steps of submerging the tar-sand in the vessel to a point where the oil previously released can reattach itself to the sand. The method encompasses the steps of submerging the tar-sand in a hot water bath, agitating the sand while thus immersed while continuously bubbling air up through the slurry to float the oil particles freed from the sand grains to the surface, continuously skimming off the oil floating on the water bath from the surface thereof, and withdrawing the clean sand from the bottom of the vessel intermittently and quickly enough to prevent the level of the water bath from falling below the top of the screws.
Description
~4497 U.S. Government surveys, among others, have indicated that in excess of lOO billion barrels of recovera61e oi`l reserves are present in the lower 48 states plus Alaska, all in the form of surface or near surface tar-sands. Some of these reserves, particularly those in Utah and Wyoming - la -3~
have a very lo~ sulfur conte~t ~nd ar~, for ~hl~ rea~cc, pa~t~cularly ~u~ le for u~c ae a source of liquid fuel~ ~nd ~p~clal purpo~e lubrlcant~.
D~pite th$s hug~ regerv~ potentlal, littlR hRs ~een done here ln tke U.S. to m~ne ~nd refinQ the~e re~ervee. In~te~d, t~e ~a~or actlvity i~
S North AmericA lla~ in the ~o-called ~th~ba~cA depo~lt ln Albert~, CQnada where Canadian Oil, Ltd. ln ~he early '70'8 w~ prod-Jclng in tha neighbcirhood of 45,00~ barrel6 of crud~ per da~. Ae le~st one C~n~di~n company, na~iely" Great Can~d~an Oil S~nds ~ ted of Toronto has pa~ent~d their proces~ for recoYeri~ oll from ~ar-~nd~, thei~ U.S. patent c~rrylng P~tent ~io. 3,607,720.
The key ~o efflclent and economical recovery of cr~de fro~
~ar-~ands ~eems to l~e in the 3~ l!.ed "flotatl~n ce ' wherein the actual ~crubbing f tbe 3~nd takes place to free the oil p~rtlcles clinging tl~htly to the eurf~ca of the ~and ~rQln~. It is necessar~ to abrald the ~and ~,rainR again~t one another to free the oil fro~ the ~ur~a~e ~hereof Wh~lQ, At the ~amQ ti~e, keeping the sand inmersed b~nesth the surf~ce of tha water baeh, Also, once the vll particle~ are freed fro~ the 6and graln8, they must be treated l.n ~uch A w~y tna~ th~y end up on the ~urface where they are acce~sible and can be skim~ed off. Flnally, and of crit~cal ~nportance, i~ the fact th~t th~ clean sand Preed of it~ cvatln~ o~ oil mu~t not be recoated therewith be~ause1 ~hen ehi~ h~ppens the ~il csn no louger b2 removed effectively due to a ti~hter adhe~lon t~at e~i~ts the secGnd tir~. The rea~on this ha?pens has to do with the re~ovaL of ~n ea~ily ~racturad acqueous lnter~ace that naturally e~-sts be~een the sand
have a very lo~ sulfur conte~t ~nd ar~, for ~hl~ rea~cc, pa~t~cularly ~u~ le for u~c ae a source of liquid fuel~ ~nd ~p~clal purpo~e lubrlcant~.
D~pite th$s hug~ regerv~ potentlal, littlR hRs ~een done here ln tke U.S. to m~ne ~nd refinQ the~e re~ervee. In~te~d, t~e ~a~or actlvity i~
S North AmericA lla~ in the ~o-called ~th~ba~cA depo~lt ln Albert~, CQnada where Canadian Oil, Ltd. ln ~he early '70'8 w~ prod-Jclng in tha neighbcirhood of 45,00~ barrel6 of crud~ per da~. Ae le~st one C~n~di~n company, na~iely" Great Can~d~an Oil S~nds ~ ted of Toronto has pa~ent~d their proces~ for recoYeri~ oll from ~ar-~nd~, thei~ U.S. patent c~rrylng P~tent ~io. 3,607,720.
The key ~o efflclent and economical recovery of cr~de fro~
~ar-~ands ~eems to l~e in the 3~ l!.ed "flotatl~n ce ' wherein the actual ~crubbing f tbe 3~nd takes place to free the oil p~rtlcles clinging tl~htly to the eurf~ca of the ~and ~rQln~. It is necessar~ to abrald the ~and ~,rainR again~t one another to free the oil fro~ the ~ur~a~e ~hereof Wh~lQ, At the ~amQ ti~e, keeping the sand inmersed b~nesth the surf~ce of tha water baeh, Also, once the vll particle~ are freed fro~ the 6and graln8, they must be treated l.n ~uch A w~y tna~ th~y end up on the ~urface where they are acce~sible and can be skim~ed off. Flnally, and of crit~cal ~nportance, i~ the fact th~t th~ clean sand Preed of it~ cvatln~ o~ oil mu~t not be recoated therewith be~ause1 ~hen ehi~ h~ppens the ~il csn no louger b2 removed effectively due to a ti~hter adhe~lon t~at e~i~ts the secGnd tir~. The rea~on this ha?pens has to do with the re~ovaL of ~n ea~ily ~racturad acqueous lnter~ace that naturally e~-sts be~een the sand
2~ gra~n a~d oil deposit coatin~ sa~e but wh~ch i0 r~oved durin~ proces~ing.
Bf~ that a/ ~t ~ y, once f3eparate~, s,;:ep~ must be taken to i~sure thAt the cle~n ~nd ~nd free~ crude oll have no opporttmity ~o gat back to~ether a~,ain~
It h~ ou beeE~ fourld lr~ aecord~ce with th~ taaehirl~ of th~
i~ta~lt ln~entlon th~t the~e a3d othe!~ ~hortcoming~ of the p~lc;r art tar-saut ~lotat~t7n calls c&n, ~ larg~ mea~ure, be ~liminate!d by the si~i;ple, yet urlobviouE~ ~edleGt of abraidl~3; the oil~coated ~and p~Lrticles ~}~a~n~t 5 ~Q ~nother ~co fre~ the o~l therefr~mt ~hile ~l~nultaneou~ly bub~ g air through the ;~ ur~a to pu6h and cArry the other~ e eutr&pped oil phrt-cle through ~he E~arad ar~d to the surf~;ce ~ tha air bubbles ri~ oth~r llovsl feattlre of the cell u}d ~cthDd of process~g ~ar-6~ds there~lt ha3 to do wlth Int:er~ittei~tly dl~charE ing the clea~ ~and froi~ the d~scharga end of 10 the ~ackPted vessel housing t~e ~lurry being proces~ed w~thout, at the same tlme, ~ppreclably 10-~2ri~ the ~lu~d 12~el there~n and mo~t especially not louering it to a level below that of t~2 acrew6 th~s prPventlng the lattar from beco~ltg recoated.
Ind~ridual feature~ of the i~proved flutation cell of the instan~
l~ventlon as ~-all as the ~thod of pro~e~8in~ tar-sat.td~ tber~l~t are ~n~n iot th~ prlor art; yet, cer ain of thc~ when used ln conbiuation wlth one ano~her acco~pli~n certaln ~ and urle~F)ec~ed rc~llt~ thaS are ~ell beyo~td the sklll of an ordina.r.y art~an kn~wled~cable in the proces~ing of tar-~arlds. For ~8t8~ce~ th~ ~e3sel it6elf ~t~ well as the cot~tterrotatl~g screw and the drives therefor are all old and haYe been 601d for yaa~s by such r~tr~tufacturers as ~azle Iron ~orks of Des ~o~nes, Iowa undar the well-knuwlt ter~ "scalp~ng tanks.' Thl~ sa~ Iowa ~,anufactu~er ~a~es a pate~ted ~al~e for u~ in ~uch tanks ~U.S. Pate~tt ~'o. 3,129,~49~ that s~n~es the bulld-up of iolld~ by ~neana of a rotat~ng paddle and tltlllze~ the increased resi~ta~ce to ~otatio~ e~periertcæ.d by the paddle to ac,uate a ~alve i~ th2 bottom of the tan~ thr~u~h ~hlch a port~on of the ~olid3 a~e d~chatged.
paddle-type s~im~er mou~t~d o~ an endle~s belt and ~ed to ~k~ the o~l floati~g on top of ehc bat~r off i~eo a r~er ~l~n~lde therecf 1B also a ~7e~ n~n e~pedient ~ flotati~a apparatus 2B exerplifi~d ~y U.S. P~tent ~o~. 745,60S a~d 3tS3g.000 both OI which re~enl ~ts~t ~uch a sy3te~ eat~n~ the coDten~ of the 3calpi~g ta~ by ~acketing ~a~.e ~-ith a ~acket throu~h ~Jhich ~te~ or ~no~ water flo~s is, lilce~l6e, a ~ore or le88 ~anaard feature of v~rlous and sundry eype of proces~ equip~ent.
~ren the broad concept of floatin~ a floatable co~tituent free of ~on-~loatin~ sollds, s~ in3 the f~oatables off the top and tak~ug the non-floatables out throu~EI the botto~ well-known e~pedletlt, espec~slly ~n ~at proces3ing, ~he follo~i~ paterL~cs ~ corporati~" such a concept to olle degree or ar~ot~er:
AlleII 1 ,147, 356 NL~to~ ~ ,2~ 590 Tollr.~n 3,616,925 Irw~ 3,9~j7,3;5 Stone ~,033,363 I~ addi~ivrl to the fore~oln~ patents whlch eler~nts folmd in applicant7s i~pro~red flotation cell~ there are a ho~t of ~)rlor ~rt patents thzt ~eal ~p~cirical~y ~,~ith proces~e~ for the recovery of bitur~ns Erom tar-Rand~3. A~ng these, and in addition to U.S. ~atent i~o. 3,607,720 already ~entioned, ~re the fo~ rnso ~el l~y 2, ~`S0, SQ0 Clark 3, 2 71, ~93 ~loyd et ~1 3 ,4Ql, 110 13ichard ek al 3,522,:L63 Lubo~yr 3, 55 5 ~ 7 ~î5 Br~ h~ll 3 ~ fiO5, 9 75 Ro~ bloo~ 3,875,046 While several of the above patents, notably, 3,607,720; 3,401,110;
Bf~ that a/ ~t ~ y, once f3eparate~, s,;:ep~ must be taken to i~sure thAt the cle~n ~nd ~nd free~ crude oll have no opporttmity ~o gat back to~ether a~,ain~
It h~ ou beeE~ fourld lr~ aecord~ce with th~ taaehirl~ of th~
i~ta~lt ln~entlon th~t the~e a3d othe!~ ~hortcoming~ of the p~lc;r art tar-saut ~lotat~t7n calls c&n, ~ larg~ mea~ure, be ~liminate!d by the si~i;ple, yet urlobviouE~ ~edleGt of abraidl~3; the oil~coated ~and p~Lrticles ~}~a~n~t 5 ~Q ~nother ~co fre~ the o~l therefr~mt ~hile ~l~nultaneou~ly bub~ g air through the ;~ ur~a to pu6h and cArry the other~ e eutr&pped oil phrt-cle through ~he E~arad ar~d to the surf~;ce ~ tha air bubbles ri~ oth~r llovsl feattlre of the cell u}d ~cthDd of process~g ~ar-6~ds there~lt ha3 to do wlth Int:er~ittei~tly dl~charE ing the clea~ ~and froi~ the d~scharga end of 10 the ~ackPted vessel housing t~e ~lurry being proces~ed w~thout, at the same tlme, ~ppreclably 10-~2ri~ the ~lu~d 12~el there~n and mo~t especially not louering it to a level below that of t~2 acrew6 th~s prPventlng the lattar from beco~ltg recoated.
Ind~ridual feature~ of the i~proved flutation cell of the instan~
l~ventlon as ~-all as the ~thod of pro~e~8in~ tar-sat.td~ tber~l~t are ~n~n iot th~ prlor art; yet, cer ain of thc~ when used ln conbiuation wlth one ano~her acco~pli~n certaln ~ and urle~F)ec~ed rc~llt~ thaS are ~ell beyo~td the sklll of an ordina.r.y art~an kn~wled~cable in the proces~ing of tar-~arlds. For ~8t8~ce~ th~ ~e3sel it6elf ~t~ well as the cot~tterrotatl~g screw and the drives therefor are all old and haYe been 601d for yaa~s by such r~tr~tufacturers as ~azle Iron ~orks of Des ~o~nes, Iowa undar the well-knuwlt ter~ "scalp~ng tanks.' Thl~ sa~ Iowa ~,anufactu~er ~a~es a pate~ted ~al~e for u~ in ~uch tanks ~U.S. Pate~tt ~'o. 3,129,~49~ that s~n~es the bulld-up of iolld~ by ~neana of a rotat~ng paddle and tltlllze~ the increased resi~ta~ce to ~otatio~ e~periertcæ.d by the paddle to ac,uate a ~alve i~ th2 bottom of the tan~ thr~u~h ~hlch a port~on of the ~olid3 a~e d~chatged.
paddle-type s~im~er mou~t~d o~ an endle~s belt and ~ed to ~k~ the o~l floati~g on top of ehc bat~r off i~eo a r~er ~l~n~lde therecf 1B also a ~7e~ n~n e~pedient ~ flotati~a apparatus 2B exerplifi~d ~y U.S. P~tent ~o~. 745,60S a~d 3tS3g.000 both OI which re~enl ~ts~t ~uch a sy3te~ eat~n~ the coDten~ of the 3calpi~g ta~ by ~acketing ~a~.e ~-ith a ~acket throu~h ~Jhich ~te~ or ~no~ water flo~s is, lilce~l6e, a ~ore or le88 ~anaard feature of v~rlous and sundry eype of proces~ equip~ent.
~ren the broad concept of floatin~ a floatable co~tituent free of ~on-~loatin~ sollds, s~ in3 the f~oatables off the top and tak~ug the non-floatables out throu~EI the botto~ well-known e~pedletlt, espec~slly ~n ~at proces3ing, ~he follo~i~ paterL~cs ~ corporati~" such a concept to olle degree or ar~ot~er:
AlleII 1 ,147, 356 NL~to~ ~ ,2~ 590 Tollr.~n 3,616,925 Irw~ 3,9~j7,3;5 Stone ~,033,363 I~ addi~ivrl to the fore~oln~ patents whlch eler~nts folmd in applicant7s i~pro~red flotation cell~ there are a ho~t of ~)rlor ~rt patents thzt ~eal ~p~cirical~y ~,~ith proces~e~ for the recovery of bitur~ns Erom tar-Rand~3. A~ng these, and in addition to U.S. ~atent i~o. 3,607,720 already ~entioned, ~re the fo~ rnso ~el l~y 2, ~`S0, SQ0 Clark 3, 2 71, ~93 ~loyd et ~1 3 ,4Ql, 110 13ichard ek al 3,522,:L63 Lubo~yr 3, 55 5 ~ 7 ~î5 Br~ h~ll 3 ~ fiO5, 9 75 Ro~ bloo~ 3,875,046 While several of the above patents, notably, 3,607,720; 3,401,110;
3,271,293 sDd 3,522,168 spQciflcally teach formin~ an emul~ion by bubbllng ir or other gaseou- nealum through the hot llquld preparstory to ski~m~ng the flotation productc off tbe top, ~one to appllcant'~ knowledge te~ches tho uni~ue ~tep of grlndlng or other~lso abralding the sand partlclRs together to free the oll ~hile slmultaneously pushing the o~l thus freed to the ~urface by bubbli~g aSr through the eolids undergoin~ thi~ abrasl~e actlon. By so dolng, applicant i8 unexpectedly able to recover so~e 93~ of the s~allable bitumen~ coatins the ~and. The percentsges of bitu~ens recover~d by other of the prior art processes i- not known ~peciflcally but one can e83il7 see that for the most part they coDstltute ~ultl-~tage proce~Ae~ which certalnly appear to be much uore co~plicated and expen~ive p r ton of oll recovered than sppllcant'~ e~entlally single ~ta~e one.
Thi~ is not to infer that appllcant'~ conplete proce~8 18 carrled out in his flotation cell because this i~ uot the ca~e. but ratber that the critical step of ~eparating the bltu~ens fro~ the sa~d i~ carried out in A ~in~le ~tep withln one plece of proce~in~ equipm~nt a~ oppo~ed to the prlor art approach of accompl~shln~ the ~epsr4tlon ln two or ~ore sta~e~.
The other a~pRct of the cell and lt~ method of uRe tbat appear~
to be novel are the subtle, but nonetheles~ important, dl~tlnctlon~
betweRn thQ prlor srt method~ and equipwent ~fied to ~egregate the floatable constituent~ fro~ the non-floatable ones. The scalping tank equlpment prevlously referred to 19 geoerally used ln ves~els when the axe~ of rotstlon of the augere are ~nclined, not level a~ ln t~e tn~ta~t flotatlon cell. Thu~, the claH~ificatlon 1~ not by means of flotatlon at all, but gravity. Even the bottom-dump valve~ are located ln dlfferent ~ectlon~ of the tank vhere solids of different ~ e ~ettle. The e~sence 114~4~7 of tbe~e prlor art Ncalpin~ 8y~tem8, thereforo, appear- to be o~e of ~olld-solld clss~lflcatlon and solid-llquid separation with llttlo, lf anyth~ng, to do wlth t~e sub~ect matter of the instant lnventlon, namel~, s~p ration of floatableo fro3 non-floatables.
The listed mRat processlng patents admlttedly deal ~ith the ~eparation of flost~bles fro~ ~on-floatablec; however, they do 80 in batch processoe for the most part, oot on a continuouq basio. ~ore importast, however, lo the fact that the chsracteri~tics of tbe floatable and non-float~ble con~tituente of the ~ix i~ entlrely diffQrent and, for thio rea~on, raugbt with entircly dlfferQnt separatlon proble~ . For instance, once th~ Eat iA freed from the lean ~eat, the latter ~ettles whlle tho fat ~loats. Such ie not the case ~ith bitumens freed fro~ tar-oaDas becauso ~uch of the oil i8 phycic~ trapped ~lthin tbe bed of ~and ev~n thou~h ru~bed free fro~ the s~rfQce of the graina. It takes ~ore than ~uot the dlfference~ ln ~pecific gravity of ~he water and oll to acco~plish tho necessarr phyoical ~eperatlon, na~el~, an ovsr abundance of very ~3all alr bubbles percolati~g u? throu~h th~ tu~blin~ plle of sand eo ae to llft the o~l particleo free ~ithout CBu~ing undue turbulence of a de~ree which ~ould result in oand particle~ being elevated to the ~urface of the ~ater bath where the oil layer lie~.
Accordingly, it i8 the princlp~l ob~ect of the present invention to provide ~ novel ~nd i~pro~ed flotatio~ cell for the extractlnn of bitumens from tsr-sands.
A second ob~ect i5 the provision of a method for ~eparatln~ cruae oil fro~ oll-coated sa~ds chitracterized by ~ novel aeratlon ~tep wherei~t an over abundance of s~ll air bubhles arc percolated throu~h the tu~blin~ send.
Artother ob~ecti~e of the ~-lthin de~cribed lnventioa ~8 to prcvide a slngle ~tage continuous ~nethod and apparatu~ cffect~ve to re~ove b~tu~clts ~ro~ tar-~ands and per~utnently ~Pparate one fro~ the other.
3~7 Still another object is the provision of such a process which results in over 90% recovery of the available bitumens while, at the same time, leaving the sand essentially clean that is being returned to the environment.
An additional object is to provide a flotation apparatus utilizing a pair of counterrotating screws turning side-by-side in horizontal relation to both scrub the oil particles ofF the sand grains and continuously advance the sand toward the discharge end of the cell as it progressively becomes cleaner and cleaner.
Further objects are to provide a process of the type afore-mentioned that is simple, efficient, good for the environment, relatively inexpensive, safe, trouble-free, versatile and susceptible of modification to suit local conditions.
Broadly stated, the invention is an apparatus for removing and separating water-immersible bitumens and the like from tar-sands which comprises: an elongate horizontally-disposed flotation vessel having intake and discharge ends defined by end walls, side walls and a bottom wall, one of said side walls being shorter than the other, said side walls and bottom wall and one end wall cooperating to define a receiver for clean sand positioned adjacent the discharge end, and the portion of said bottom wall between the other of said end walls and said receiver being rounded to confornl to the contour of a pair of screw conveyors mounted side-by-side therein; means located at the intake end for intro-ducing tar-sand in the form of an aqueous slurry into the vesseli a pair of screw conveyors journalled for rotation in side-by-side parallel relation in the round-bottomed portion of the vessel; drive means con-nected to the screw conveyors operative to counterrotate same in a direction to advance the slurry introduced at the intake end and deposit the latter in the receiver; said screws being effective upon rotation to rub the sand grains together and scrub the wa-ter immiscible materials from the surface thereof; aerating means extending along the bottom of the vessel 3'7 alongside the screw conveyors, said means being operative upon connection to a source of water and air under pressure to direct air bubbles upwardly at a rate and in a quantity effective to lift the freed immisci~les through the sand and deposit same on the surfacei open-topped means positioned alongside the overflow wier defining a catch basin for the immiscibles floating on the surface of the water in the vessel; paddle-carrying means running transversely of the vessel between the side walls for skimming the immiscibles floating on the surface of the water over the shorter of the two and into the catch basin; and valve means in the bottom of the receiver operative upon actuation to discharge some of the sand contained therein while maintaining the liquid level in the vessel at a depth above that of the sand contained therein.
In another broad aspect of the invention, a method is pro-vided for removing water-immiscible bitumens and the like from the surface of tar-sands and separating same from the sand grains which includes the steps of: rubbing the coated sand grains together under water by tumbling them between two counterrotating screw conveyors, bubbling an air-water mixture up through the descending sand grains at a rate and in a quantity effec-tive to lift the immiscibles free oF the sand and deposit same on the surface of the water, skimming the immiscibles thus deposited off the surface of the water while moving the progressively cleaner sand grains toward one end by means of the screw conveyors, and dumping the clean sand out the bottom while maintaining the water level above that of the sand.
Other objects will be in part apparent and in part pointed out specifically hereinafter in connection with the drawings that follow, and in which:
Figure 1 is a perspective view of the flotation cell, portions of which have been broken away to conserve space while other portions have been treated in a similar manner to more clearly reveal the interior construction;
- 7a -3'7 Figure 2 is a fragmentary perspective to the same scale as Figure 1 showing the overflow launders and the manifold interconnecting same;
Figure 3 is a view showing the cell to a somewhat smaller scale partly in section and partly in elevation;
Figure 4 is a transverse section to an enlarged scale taken along line 4--4 of Figure 3, the jacket for heating the vessel having been removed;
Figure 5 is a diametrical section to even a further enlarged scale showing the air-aspirating venturi that percolates an over abundance of air and water up through the tumbling sand bed at all times; and, - 7b -Fig. 6 is a fr~ nt~r~ ae.c~lon to ~ ~cal~ ~oD~ewh~t la~r ~ha~
Plg . 1 tal~eD al~g li~ ~ 6 o the 1 ~ttsr f igure .
1144~97 Referring ne~t to the drawlngs fQr detallet descrlption of the pre~ent inventlon, and lnltially to ~lg. 1 for thls purpose. reference num~tal lO ha- boen selected to broadly des1gnate the flotatlon cell while numeral 12 de~lgnatee the ~acheted ve~sel ~lthin which the oll 14 ls scrubbed from the sand 16 and floated free thereof on the surface of a ~ater bath 18 into whlch the tar-sand i~ lntroduced through lnlet 20. In the speclflc form shown, the ves~el comprlse~ an open-topped elongste trou~h~ e structure cloced at both end~ by end ~all~ 22. The ~ide ~811~ 24 are curved about a larg~ rat~us at the polnt wher- they ~oln the bottom 26. ~oused ln~lde the~
curved corners 2R are a ~air of counterrotating screw conveyors 30 arranged in horlzontally-spaced side-by-s~de parallal relation. The corner CurvatUrQ
is eseQntially concentrlc vlth the a~e~ of rotatlon of the ~crew~ whil~
leav~ng n ~mall gap 32 therebetween in a manner well ~nown in the screw . conveyor art. A~ those screwY rotste ln the dl~ectlous lndlcated by thQ
arrow~ lg. 4, they tumble the tar-sand 80 A~ to rub thc grain~ together and scrub the oil from the sand partlcle~ Yhlle, at the samQ time, moving th~ progres~lvely cleaner ~and toward the dlscharge end of the cell, the lattQr h~v~ng been indlcatet broadly by reference numeral 34.
As illustrated in Flgs. 2 and 3 to ~hlch detalled reference wlll n2xt be made, the top of the vessel l~ dlvided longitudlnally into three oompart~ent~, ~, B ~cd C, eacb of which i~ covered by a lld 36. These figures along w~th ~i8~ 1 and 4 show that hou~ed benea~h each lid i3 a ski$mer subas3embly that has been lndicated brosdly by reference numeral 38 and whlch co~pr~es ~n e~dles~ belt and fli~ht conveyor runnln~
hor~zontally instead of vertlcally. O~e ~uch ~ubas~embly 18 provided ln each co~partmR~t and they functlo~ to s~;im the oll floating on top o~ the water both off to one ~lde ~nd Into overflow launders 40 po~ltioned along~lde each co~partment.
As i3 r~ose cle8rly ~een ~ P~,. 4, or~ side ~all 24S of the ve8sel ~8 short3r than the o~her and its upp~r edge i~ fclded over to produce a ~i~r 42 o~er whlch ~h~ oll is s~2pt by the sklm~er BUbaE~E~eE~blie8 38 into the launder~ ~long~id~ ther~o~ Flg. 2 it can be seen th~t each lau~d~r 40 ha~ a ~opper-like 810pi~g botto~ 44 that collect~
the o~l at dischar~e ope~lngs 46 which le~d i~t~ oil collectlon li~es 4B.
Iook~ug next at Fl~ and 4, lt c~n be s2en that ~i~gle co~mon drlve ~d driven ~haf~s 5~ and 52, respectively, sr2 ~ournalled for rotatio~
along opposite side~ of tbe ves~el 12 near its top edg~ and above wier 42.
Rollers 54 are fixed ~o each ~haft for rot~tlon therewlth ~ithin each of the three compar~ments in tran~erQely-allgned relatlon. An eDdless balt 56 carrying the paddl~ l~ke fli~ht~ 58 i8 reaved around each palr of rollere to co~plete the ~ki~mer subanse~bly. A gear motor or ~imllar drive 60 connected to dri~e shaft 50 drlves all t~rec skin~Der ~ubas~e~iblie~
simultan~ou~ly and ic a direction to a~lm the oil into the overfl~w launders.
Other arrRngeme~ts can~ of course, be u6ed to drlve the ~klr..mer~ including tbat of taklng the pcr~er to dr~ve them from the ~ain drive 62 that operntes the counterrotating screw9.
A~ seen ln ~fg8. 1, 3 and 4, the main ve~r3el 12 1~ ~h~n mounted on I-beam~ 64 but, here a~ain, ~ny ~ultable base wlll ~uffic~ a~d could, if Deces~ary9 be u~ed ~n place ehereOf. Likewise, thc ve~ael 12 i~ sho~a wlth itr~ bottom and both ~lder~ covered wi~ch a ~.o.c~lcet 66 through whfch uet~r, ste~m or sDme other heat exchange mediu~ can be circ~ated 1Q r~uf ~icie~t quantltl~ and at a high enough temperature to maintal.n the water ~n~ide tne ~e~el at bet~een :tpproxlm~tely 1~0--2~0F, Steam jacketed vesr~el~ are well ~ n In the Art and no claim 1~ predlcated ~hereon. ~nstead, the only ~iz~ific~nce of the Ja.cketed ve~el ~ .o provide ~n envlronmen~ uhera the water bath wlll be 3~intalned ~ithin the afore~ntioned te~perature ran~e.
DriVQ 62 for ehe screw conveyor~ is, li~e~e, conventional and, in the partlcular form shown 1~ lncludes a belt ~nd pulley drlve fro~ a prime ver (not sh~wn~ that 1~ ef~ectlve to rotate input ~haft 6~. Input shaft 68, in turn, rotatea the r~ght screw conveyor shaft 70R by ~eans of ~e~hed gears 72 a~d 74. Shaft 70R ~180 car~les e ~ecoud gear 76 ~hich meshe with Idler 78 that 1~ turn ~eshes with geRr ~0 on shaft 70L to rotate thc lat~er i~ ~ direction oppo~lte to that in which shaft 70R turn~.
1~ The auger flight~n~ 8ZR ~nd 82~ must be of the oppo~itQ hand in order for both ~crews when turned In oppo31te direc~ions (~ee arrows in F~go 4) to drive the s~nd forwardly toward th~ discharge end, l.a. the right-hand ~hsft 70R turn~ counterclockwlse when vle~ed from the inta~e end of the cell And it~ fli~htln~ ~2R must, therefore, have a rlght-hand thread to L5 dr~ve the sand forward].y. Conversely, shaft 70L turn8 clock~wi8~ ~9 8een from the lntakQ end and its fl~shting 82L must, ~herefore, be left h~nded to advancQ the sand. ~'ear tr~ 72-80 18 hou~ed in a cuitable hou~ing ~4 as shown.
~Ir~i, with particular reference once ~gain to Fl~s. 1, 3 and 4, lt will be ~ee~ that a p~pe 86 runf3 along the bottom oP the ~es~el betwee~
the scre~s fro~ the Intake end to ~ point of ter~inatio~ ~ust short of bo~ 88 whera the cle~n sand Is collected preparatory to being du~l?ed out the ~otto~ ~hro~l"h p4pefi 90. Ths p~pe 86 hae aperturef~ 92 spaced alo~3 the top af~ uell as on both sldes thereof (~ee Fi~
At the polnt uhere pip2 86 enter~ the b~lkhf-~ad os end wall 22 at the Pront end o~ the ve~sel, lt i~ f-it.ed ~ith an air-~spi~ting venturI 94 o~ conventional des~f~n. Water enters the ~venturi and ~spirRteA air i~ the cf~nventional ~ nar preparR~f-ory to dscharg~ng ~a~f~ ndernfeath ~he f;~nd 114~97 - lying ln the botto~ of the cell As the ~crews turn, they rub and abrald the sand grais~ together freein8 the oll partlcles therefro~; hovcver, the~a particle- ~aall~ become physicallr trapped ~n the sand desplte the fact that tSey no lonser coat sa~e, It haA been found that b~
si~ultaneouJl~ flushing and aeratin~ thls sand ~hlle lt 19 being tu~bled, the rislng d r bubble~ push the oll partlcle~ through the E~nt and carry the~ to the ourface ~here they can be 3cavanged It ~8 slgDlflcant that the aeration be in the for~ of very tlny bubbles that will ~i~rate upwardl~
through the ~and witbout unduly agitating lt to the point where ~o~e of it ~ puohed all the way to the surface of the water bath to becore recoated with oll and be ~ept off into the launder by tha ski~er Flnall~, wlth brlef reference to Fig 6 lt wlll be seen that bo- 88 contalnlng the botto_ dump tubes or pipes ~0 ib fitted with a plurallty of velve ~uba~emblies that have been lndicated ln a general way by reference nu~ral 96 and ~hlch are, once aga~n, of conventional constructlon, the particular one Illu~tratQa bein~ ~l~llar to tbat whlch for~s ~ub~ect ~atter of U S. Patent No 3,129,849 Essentlall~, the bulld-up of sand in the botto~ of bos 88 1~ sen~ed by rotatlng paddle 98 AB thls padtle encounters increaRed reslstance toward rotatlon by rRason of the bulld-up of aand therearound, lts shaft 100 torque4 a~alnst the actlon of a tenslon Hprlng (not 3bown) hou~ed in hou~in~ 102 Thi8 turnlng actlon clo~es an electrical clrcult represented by llnk 104 that energize~ a ~otor 106 whlch screws shaft 108 do~n and opens v~lve 110 thus ~llowing sand to escape through plpe 90 Once the level of the sand hae dropped bel~w p~ddle 98 80 that it can turn reely agaln, tbe spring inslde hou~ing 1~2 returns the electrical elrcu~t to Its origlnal conditlon where it becomes operative to turn ~haft 108 in the rever~e dlrection thus reclosing valve 110 before shutting off and waltlng for a ~ubseqneIIt l~itlatlou of lts operating cycl~. The~e valv~ are effeeti~e to l~ten~lttently aod lndependentl~ ~ump cle!ian sand ~ro~ box 88 without lo~eriog the fluid level in the cell to a point belt~w the ievel o~ tba ~and co~taio~d therein.
Thi~ is not to infer that appllcant'~ conplete proce~8 18 carrled out in his flotation cell because this i~ uot the ca~e. but ratber that the critical step of ~eparating the bltu~ens fro~ the sa~d i~ carried out in A ~in~le ~tep withln one plece of proce~in~ equipm~nt a~ oppo~ed to the prlor art approach of accompl~shln~ the ~epsr4tlon ln two or ~ore sta~e~.
The other a~pRct of the cell and lt~ method of uRe tbat appear~
to be novel are the subtle, but nonetheles~ important, dl~tlnctlon~
betweRn thQ prlor srt method~ and equipwent ~fied to ~egregate the floatable constituent~ fro~ the non-floatable ones. The scalping tank equlpment prevlously referred to 19 geoerally used ln ves~els when the axe~ of rotstlon of the augere are ~nclined, not level a~ ln t~e tn~ta~t flotatlon cell. Thu~, the claH~ificatlon 1~ not by means of flotatlon at all, but gravity. Even the bottom-dump valve~ are located ln dlfferent ~ectlon~ of the tank vhere solids of different ~ e ~ettle. The e~sence 114~4~7 of tbe~e prlor art Ncalpin~ 8y~tem8, thereforo, appear- to be o~e of ~olld-solld clss~lflcatlon and solid-llquid separation with llttlo, lf anyth~ng, to do wlth t~e sub~ect matter of the instant lnventlon, namel~, s~p ration of floatableo fro3 non-floatables.
The listed mRat processlng patents admlttedly deal ~ith the ~eparation of flost~bles fro~ ~on-floatablec; however, they do 80 in batch processoe for the most part, oot on a continuouq basio. ~ore importast, however, lo the fact that the chsracteri~tics of tbe floatable and non-float~ble con~tituente of the ~ix i~ entlrely diffQrent and, for thio rea~on, raugbt with entircly dlfferQnt separatlon proble~ . For instance, once th~ Eat iA freed from the lean ~eat, the latter ~ettles whlle tho fat ~loats. Such ie not the case ~ith bitumens freed fro~ tar-oaDas becauso ~uch of the oil i8 phycic~ trapped ~lthin tbe bed of ~and ev~n thou~h ru~bed free fro~ the s~rfQce of the graina. It takes ~ore than ~uot the dlfference~ ln ~pecific gravity of ~he water and oll to acco~plish tho necessarr phyoical ~eperatlon, na~el~, an ovsr abundance of very ~3all alr bubbles percolati~g u? throu~h th~ tu~blin~ plle of sand eo ae to llft the o~l particleo free ~ithout CBu~ing undue turbulence of a de~ree which ~ould result in oand particle~ being elevated to the ~urface of the ~ater bath where the oil layer lie~.
Accordingly, it i8 the princlp~l ob~ect of the present invention to provide ~ novel ~nd i~pro~ed flotatio~ cell for the extractlnn of bitumens from tsr-sands.
A second ob~ect i5 the provision of a method for ~eparatln~ cruae oil fro~ oll-coated sa~ds chitracterized by ~ novel aeratlon ~tep wherei~t an over abundance of s~ll air bubhles arc percolated throu~h the tu~blin~ send.
Artother ob~ecti~e of the ~-lthin de~cribed lnventioa ~8 to prcvide a slngle ~tage continuous ~nethod and apparatu~ cffect~ve to re~ove b~tu~clts ~ro~ tar-~ands and per~utnently ~Pparate one fro~ the other.
3~7 Still another object is the provision of such a process which results in over 90% recovery of the available bitumens while, at the same time, leaving the sand essentially clean that is being returned to the environment.
An additional object is to provide a flotation apparatus utilizing a pair of counterrotating screws turning side-by-side in horizontal relation to both scrub the oil particles ofF the sand grains and continuously advance the sand toward the discharge end of the cell as it progressively becomes cleaner and cleaner.
Further objects are to provide a process of the type afore-mentioned that is simple, efficient, good for the environment, relatively inexpensive, safe, trouble-free, versatile and susceptible of modification to suit local conditions.
Broadly stated, the invention is an apparatus for removing and separating water-immersible bitumens and the like from tar-sands which comprises: an elongate horizontally-disposed flotation vessel having intake and discharge ends defined by end walls, side walls and a bottom wall, one of said side walls being shorter than the other, said side walls and bottom wall and one end wall cooperating to define a receiver for clean sand positioned adjacent the discharge end, and the portion of said bottom wall between the other of said end walls and said receiver being rounded to confornl to the contour of a pair of screw conveyors mounted side-by-side therein; means located at the intake end for intro-ducing tar-sand in the form of an aqueous slurry into the vesseli a pair of screw conveyors journalled for rotation in side-by-side parallel relation in the round-bottomed portion of the vessel; drive means con-nected to the screw conveyors operative to counterrotate same in a direction to advance the slurry introduced at the intake end and deposit the latter in the receiver; said screws being effective upon rotation to rub the sand grains together and scrub the wa-ter immiscible materials from the surface thereof; aerating means extending along the bottom of the vessel 3'7 alongside the screw conveyors, said means being operative upon connection to a source of water and air under pressure to direct air bubbles upwardly at a rate and in a quantity effective to lift the freed immisci~les through the sand and deposit same on the surfacei open-topped means positioned alongside the overflow wier defining a catch basin for the immiscibles floating on the surface of the water in the vessel; paddle-carrying means running transversely of the vessel between the side walls for skimming the immiscibles floating on the surface of the water over the shorter of the two and into the catch basin; and valve means in the bottom of the receiver operative upon actuation to discharge some of the sand contained therein while maintaining the liquid level in the vessel at a depth above that of the sand contained therein.
In another broad aspect of the invention, a method is pro-vided for removing water-immiscible bitumens and the like from the surface of tar-sands and separating same from the sand grains which includes the steps of: rubbing the coated sand grains together under water by tumbling them between two counterrotating screw conveyors, bubbling an air-water mixture up through the descending sand grains at a rate and in a quantity effec-tive to lift the immiscibles free oF the sand and deposit same on the surface of the water, skimming the immiscibles thus deposited off the surface of the water while moving the progressively cleaner sand grains toward one end by means of the screw conveyors, and dumping the clean sand out the bottom while maintaining the water level above that of the sand.
Other objects will be in part apparent and in part pointed out specifically hereinafter in connection with the drawings that follow, and in which:
Figure 1 is a perspective view of the flotation cell, portions of which have been broken away to conserve space while other portions have been treated in a similar manner to more clearly reveal the interior construction;
- 7a -3'7 Figure 2 is a fragmentary perspective to the same scale as Figure 1 showing the overflow launders and the manifold interconnecting same;
Figure 3 is a view showing the cell to a somewhat smaller scale partly in section and partly in elevation;
Figure 4 is a transverse section to an enlarged scale taken along line 4--4 of Figure 3, the jacket for heating the vessel having been removed;
Figure 5 is a diametrical section to even a further enlarged scale showing the air-aspirating venturi that percolates an over abundance of air and water up through the tumbling sand bed at all times; and, - 7b -Fig. 6 is a fr~ nt~r~ ae.c~lon to ~ ~cal~ ~oD~ewh~t la~r ~ha~
Plg . 1 tal~eD al~g li~ ~ 6 o the 1 ~ttsr f igure .
1144~97 Referring ne~t to the drawlngs fQr detallet descrlption of the pre~ent inventlon, and lnltially to ~lg. 1 for thls purpose. reference num~tal lO ha- boen selected to broadly des1gnate the flotatlon cell while numeral 12 de~lgnatee the ~acheted ve~sel ~lthin which the oll 14 ls scrubbed from the sand 16 and floated free thereof on the surface of a ~ater bath 18 into whlch the tar-sand i~ lntroduced through lnlet 20. In the speclflc form shown, the ves~el comprlse~ an open-topped elongste trou~h~ e structure cloced at both end~ by end ~all~ 22. The ~ide ~811~ 24 are curved about a larg~ rat~us at the polnt wher- they ~oln the bottom 26. ~oused ln~lde the~
curved corners 2R are a ~air of counterrotating screw conveyors 30 arranged in horlzontally-spaced side-by-s~de parallal relation. The corner CurvatUrQ
is eseQntially concentrlc vlth the a~e~ of rotatlon of the ~crew~ whil~
leav~ng n ~mall gap 32 therebetween in a manner well ~nown in the screw . conveyor art. A~ those screwY rotste ln the dl~ectlous lndlcated by thQ
arrow~ lg. 4, they tumble the tar-sand 80 A~ to rub thc grain~ together and scrub the oil from the sand partlcle~ Yhlle, at the samQ time, moving th~ progres~lvely cleaner ~and toward the dlscharge end of the cell, the lattQr h~v~ng been indlcatet broadly by reference numeral 34.
As illustrated in Flgs. 2 and 3 to ~hlch detalled reference wlll n2xt be made, the top of the vessel l~ dlvided longitudlnally into three oompart~ent~, ~, B ~cd C, eacb of which i~ covered by a lld 36. These figures along w~th ~i8~ 1 and 4 show that hou~ed benea~h each lid i3 a ski$mer subas3embly that has been lndicated brosdly by reference numeral 38 and whlch co~pr~es ~n e~dles~ belt and fli~ht conveyor runnln~
hor~zontally instead of vertlcally. O~e ~uch ~ubas~embly 18 provided ln each co~partmR~t and they functlo~ to s~;im the oll floating on top o~ the water both off to one ~lde ~nd Into overflow launders 40 po~ltioned along~lde each co~partment.
As i3 r~ose cle8rly ~een ~ P~,. 4, or~ side ~all 24S of the ve8sel ~8 short3r than the o~her and its upp~r edge i~ fclded over to produce a ~i~r 42 o~er whlch ~h~ oll is s~2pt by the sklm~er BUbaE~E~eE~blie8 38 into the launder~ ~long~id~ ther~o~ Flg. 2 it can be seen th~t each lau~d~r 40 ha~ a ~opper-like 810pi~g botto~ 44 that collect~
the o~l at dischar~e ope~lngs 46 which le~d i~t~ oil collectlon li~es 4B.
Iook~ug next at Fl~ and 4, lt c~n be s2en that ~i~gle co~mon drlve ~d driven ~haf~s 5~ and 52, respectively, sr2 ~ournalled for rotatio~
along opposite side~ of tbe ves~el 12 near its top edg~ and above wier 42.
Rollers 54 are fixed ~o each ~haft for rot~tlon therewlth ~ithin each of the three compar~ments in tran~erQely-allgned relatlon. An eDdless balt 56 carrying the paddl~ l~ke fli~ht~ 58 i8 reaved around each palr of rollere to co~plete the ~ki~mer subanse~bly. A gear motor or ~imllar drive 60 connected to dri~e shaft 50 drlves all t~rec skin~Der ~ubas~e~iblie~
simultan~ou~ly and ic a direction to a~lm the oil into the overfl~w launders.
Other arrRngeme~ts can~ of course, be u6ed to drlve the ~klr..mer~ including tbat of taklng the pcr~er to dr~ve them from the ~ain drive 62 that operntes the counterrotating screw9.
A~ seen ln ~fg8. 1, 3 and 4, the main ve~r3el 12 1~ ~h~n mounted on I-beam~ 64 but, here a~ain, ~ny ~ultable base wlll ~uffic~ a~d could, if Deces~ary9 be u~ed ~n place ehereOf. Likewise, thc ve~ael 12 i~ sho~a wlth itr~ bottom and both ~lder~ covered wi~ch a ~.o.c~lcet 66 through whfch uet~r, ste~m or sDme other heat exchange mediu~ can be circ~ated 1Q r~uf ~icie~t quantltl~ and at a high enough temperature to maintal.n the water ~n~ide tne ~e~el at bet~een :tpproxlm~tely 1~0--2~0F, Steam jacketed vesr~el~ are well ~ n In the Art and no claim 1~ predlcated ~hereon. ~nstead, the only ~iz~ific~nce of the Ja.cketed ve~el ~ .o provide ~n envlronmen~ uhera the water bath wlll be 3~intalned ~ithin the afore~ntioned te~perature ran~e.
DriVQ 62 for ehe screw conveyor~ is, li~e~e, conventional and, in the partlcular form shown 1~ lncludes a belt ~nd pulley drlve fro~ a prime ver (not sh~wn~ that 1~ ef~ectlve to rotate input ~haft 6~. Input shaft 68, in turn, rotatea the r~ght screw conveyor shaft 70R by ~eans of ~e~hed gears 72 a~d 74. Shaft 70R ~180 car~les e ~ecoud gear 76 ~hich meshe with Idler 78 that 1~ turn ~eshes with geRr ~0 on shaft 70L to rotate thc lat~er i~ ~ direction oppo~lte to that in which shaft 70R turn~.
1~ The auger flight~n~ 8ZR ~nd 82~ must be of the oppo~itQ hand in order for both ~crews when turned In oppo31te direc~ions (~ee arrows in F~go 4) to drive the s~nd forwardly toward th~ discharge end, l.a. the right-hand ~hsft 70R turn~ counterclockwlse when vle~ed from the inta~e end of the cell And it~ fli~htln~ ~2R must, therefore, have a rlght-hand thread to L5 dr~ve the sand forward].y. Conversely, shaft 70L turn8 clock~wi8~ ~9 8een from the lntakQ end and its fl~shting 82L must, ~herefore, be left h~nded to advancQ the sand. ~'ear tr~ 72-80 18 hou~ed in a cuitable hou~ing ~4 as shown.
~Ir~i, with particular reference once ~gain to Fl~s. 1, 3 and 4, lt will be ~ee~ that a p~pe 86 runf3 along the bottom oP the ~es~el betwee~
the scre~s fro~ the Intake end to ~ point of ter~inatio~ ~ust short of bo~ 88 whera the cle~n sand Is collected preparatory to being du~l?ed out the ~otto~ ~hro~l"h p4pefi 90. Ths p~pe 86 hae aperturef~ 92 spaced alo~3 the top af~ uell as on both sldes thereof (~ee Fi~
At the polnt uhere pip2 86 enter~ the b~lkhf-~ad os end wall 22 at the Pront end o~ the ve~sel, lt i~ f-it.ed ~ith an air-~spi~ting venturI 94 o~ conventional des~f~n. Water enters the ~venturi and ~spirRteA air i~ the cf~nventional ~ nar preparR~f-ory to dscharg~ng ~a~f~ ndernfeath ~he f;~nd 114~97 - lying ln the botto~ of the cell As the ~crews turn, they rub and abrald the sand grais~ together freein8 the oll partlcles therefro~; hovcver, the~a particle- ~aall~ become physicallr trapped ~n the sand desplte the fact that tSey no lonser coat sa~e, It haA been found that b~
si~ultaneouJl~ flushing and aeratin~ thls sand ~hlle lt 19 being tu~bled, the rislng d r bubble~ push the oll partlcle~ through the E~nt and carry the~ to the ourface ~here they can be 3cavanged It ~8 slgDlflcant that the aeration be in the for~ of very tlny bubbles that will ~i~rate upwardl~
through the ~and witbout unduly agitating lt to the point where ~o~e of it ~ puohed all the way to the surface of the water bath to becore recoated with oll and be ~ept off into the launder by tha ski~er Flnall~, wlth brlef reference to Fig 6 lt wlll be seen that bo- 88 contalnlng the botto_ dump tubes or pipes ~0 ib fitted with a plurallty of velve ~uba~emblies that have been lndicated ln a general way by reference nu~ral 96 and ~hlch are, once aga~n, of conventional constructlon, the particular one Illu~tratQa bein~ ~l~llar to tbat whlch for~s ~ub~ect ~atter of U S. Patent No 3,129,849 Essentlall~, the bulld-up of sand in the botto~ of bos 88 1~ sen~ed by rotatlng paddle 98 AB thls padtle encounters increaRed reslstance toward rotatlon by rRason of the bulld-up of aand therearound, lts shaft 100 torque4 a~alnst the actlon of a tenslon Hprlng (not 3bown) hou~ed in hou~in~ 102 Thi8 turnlng actlon clo~es an electrical clrcult represented by llnk 104 that energize~ a ~otor 106 whlch screws shaft 108 do~n and opens v~lve 110 thus ~llowing sand to escape through plpe 90 Once the level of the sand hae dropped bel~w p~ddle 98 80 that it can turn reely agaln, tbe spring inslde hou~ing 1~2 returns the electrical elrcu~t to Its origlnal conditlon where it becomes operative to turn ~haft 108 in the rever~e dlrection thus reclosing valve 110 before shutting off and waltlng for a ~ubseqneIIt l~itlatlou of lts operating cycl~. The~e valv~ are effeeti~e to l~ten~lttently aod lndependentl~ ~ump cle!ian sand ~ro~ box 88 without lo~eriog the fluid level in the cell to a point belt~w the ievel o~ tba ~and co~taio~d therein.
Claims (10)
1. The apparatus for removing and separating water-immersible bitumens and the like from sat-sands which comprises: an elongate horizontally-disposed flotation vessel having intake and discharge ends defined by end walls, side walls and a bottom wall, one of said side walls being shorter than the other, said side walls and bottom wall and one end wall cooperating to define a receiver for clean sand positioned adjacent the discharge end, and the portion of said bottom was between the other of said end walls and said receiver being rounded to conform to the contour of a pair of screw conveyors mounted side-by-side therein; means located at the intake end for introducing tar-sand in the form of an aqueous slurry into the vessel; a pair of screw conveyors journalled for rotation in side-by-side parallel relation in the round-bottomed portion of the vessel;
drive means connected to the screw conveyors operative to counterrotate same in a direction to advance the slurry introduced at the intake end and deposit the latter in the receiver; said screws being effective upon rotation to rub the sand grains together and scrub the water immiscible materials from the surface thereof; aerating means extending along the bottom of the vessel alongside the screw conveyors, said means being operative upon connection to a source of water and air under pressure to direct air bubbles upwardly at a rate and in a quantity effective to lift the freed immiscibles through the sand and deposit same on the surface' open-topped means positioned alongside the overflow wier defining a catch basin for the immiscibles floating on the surface of the water in the vessel;
paddle-carrying means running transversely of the vessel between the side walls for skimming the immiscibles floating on the surface of the water over the shorter of the two and into the catch basin; and valve means in the bottom of the receiver operative upon actuation to discharge some of the sand contained therein while maintaining the liquid level in the vessel at a depth above that of the sand contained therein.
drive means connected to the screw conveyors operative to counterrotate same in a direction to advance the slurry introduced at the intake end and deposit the latter in the receiver; said screws being effective upon rotation to rub the sand grains together and scrub the water immiscible materials from the surface thereof; aerating means extending along the bottom of the vessel alongside the screw conveyors, said means being operative upon connection to a source of water and air under pressure to direct air bubbles upwardly at a rate and in a quantity effective to lift the freed immiscibles through the sand and deposit same on the surface' open-topped means positioned alongside the overflow wier defining a catch basin for the immiscibles floating on the surface of the water in the vessel;
paddle-carrying means running transversely of the vessel between the side walls for skimming the immiscibles floating on the surface of the water over the shorter of the two and into the catch basin; and valve means in the bottom of the receiver operative upon actuation to discharge some of the sand contained therein while maintaining the liquid level in the vessel at a depth above that of the sand contained therein.
2. The apparatus as set forth in claim 1 wherein a heated jacket encases the side walls and bottom of the vessel for heating the contents thereof.
3. The apparatus as set forth in claim 1 wherein the aerating means includes an aspirator open to the atmosphere.
4. The apparatus as set forth in claim 1 wherein the drive means turns the screw conveyors in directions where they move the sand over the top thereof and into position therebetween; and, in which the aerating means is located between the screw conveyors and underneath them so as to feed the water-air mixture upwardly in countercurrent flow relation to the descending sand particles.
5. The apparatus as set forth in claim 1 wherein the valve means open in response to a build-up of sand within the receiver above a preset level.
6. The apparatus as set forth in claim 5 wherein the valve means close in response to the lowering of the sand level below said preset level.
7, The method for removing water-immiscible bitumens and the like from the surface of tar-sands and separating same from the sand grains which includes the steps of: rubbing the coated sand grains together under water by tumbling them between to counterrotating screw conveyors, bubbling and air-water mixture up through the descending sand grains at a rate and in a quantity effective to lift the immiscibles free of the sand and deposit same on the surface of the water, skimming the immiscibles thus deposited off the surface of the water while moving the progressively cleaner sand grains toward one end by means of the screw conveyors, and dumping the clean send out the bottom while maintaining the water level above that of the sand.
8. The method as set forth in claim 7 wherein the sand is tumbled down between the screw conveyors and the air-water mixture rises therebetween in countercurrent flow relation to said descending sand.
9. The method as set forth in claim 7 wherein the immiscibles floating on the surface of the water are skimmed off to one side while the progressively cleaner sand is moved along toward one end.
10. The method as set forth in claim 7 in which the build-up of sand is sensed and its build-up to a predetermined level is used to dump same before its level rises above that of the water.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US3839879A | 1979-05-14 | 1979-05-14 | |
| US038,398 | 1993-03-29 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1144497A true CA1144497A (en) | 1983-04-12 |
Family
ID=21899725
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000351870A Expired CA1144497A (en) | 1979-05-14 | 1980-05-13 | Flotation method and apparatus for recovering crude oil from tar-sand |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1144497A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101863606A (en) * | 2010-06-08 | 2010-10-20 | 利津县瑞海石油科技有限责任公司 | Harmless treatment process for sludge and sand of crude oil |
| WO2014113894A1 (en) * | 2013-01-25 | 2014-07-31 | Calaeris Energy & Environment Ltd. | Turbulent vacuum thermal separation methods and systems |
-
1980
- 1980-05-13 CA CA000351870A patent/CA1144497A/en not_active Expired
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101863606A (en) * | 2010-06-08 | 2010-10-20 | 利津县瑞海石油科技有限责任公司 | Harmless treatment process for sludge and sand of crude oil |
| WO2014113894A1 (en) * | 2013-01-25 | 2014-07-31 | Calaeris Energy & Environment Ltd. | Turbulent vacuum thermal separation methods and systems |
| CN105008490A (en) * | 2013-01-25 | 2015-10-28 | 卡拉厄里斯能源与环境有限公司 | Turbulent vacuum thermal separation methods and systems |
| EP2948526A4 (en) * | 2013-01-25 | 2016-08-24 | Calaeris Energy & Environment Ltd | Turbulent vacuum thermal separation methods and systems |
| CN105008490B (en) * | 2013-01-25 | 2017-03-29 | 卡拉厄里斯能源与环境有限公司 | Turbulent flow Vacuum Heat separation method and system |
| AU2014210348B2 (en) * | 2013-01-25 | 2017-06-22 | Calaeris Energy And Environment Ltd. | Turbulent vacuum thermal separation methods and systems |
| US9939197B2 (en) | 2013-01-25 | 2018-04-10 | Calaeris Energy + Environment Ltd. | Turbulent vacuum thermal separation methods and systems |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4324652A (en) | Flotation method and apparatus for recovering crude oil from tar-sand | |
| US4651762A (en) | Agitation parts degreaser | |
| US4375264A (en) | Method and apparatus for segregating and separately recovering solids of different densities | |
| US5100545A (en) | Separation tank | |
| US5316029A (en) | Oil separator | |
| US20140014589A1 (en) | Method for cleaning drilling fluid in rock sampling drilling and a cleaning unit | |
| US5957301A (en) | Method and apparatus for the separation of materials having different densities | |
| US5950839A (en) | Method and apparatus for the separation of manure and sand | |
| CN106830593A (en) | Oily sludge three-phase separating device and its separation method | |
| US4096066A (en) | Treating contaminated liquids | |
| GB2131486A (en) | Pumps combined with agitators | |
| CN212050790U (en) | Novel petroleum gathering and transporting sewage treatment device | |
| US992629A (en) | Apparatus for dewatering and classifying ores. | |
| US2933187A (en) | Method and apparatus for flotation separation of lightweight aggregate and product | |
| US2606660A (en) | Apparatus for separating solids of relatively different wettabilities | |
| CA1144497A (en) | Flotation method and apparatus for recovering crude oil from tar-sand | |
| CA2047379A1 (en) | Floatation separation system | |
| CN208087329U (en) | A kind of air floatation machine | |
| CN211169910U (en) | Oily sewage treatment device for oil field gathering and transportation | |
| DE19854317B4 (en) | Method of removing a substance floating on the surface of a liquid | |
| CN206591017U (en) | Oily sludge three-phase separating device | |
| JP5605490B1 (en) | Pressurized floating scum separation treatment device | |
| KR870001854A (en) | Method and apparatus for separating solid from liquid | |
| US2168942A (en) | Flotation apparatus | |
| US4302339A (en) | Beach cleaning method |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |