Yan Language:
Lucas Rojas Mendoza, ST Equipment & Technology, USA
lrojasmendoza@steqtech.com
Frank Hrach, ST Equipment & Technology, USA
Kyle Flynn, ST Equipment & Technology, USA
Abhishek Gupta, ST Equipment & Technology, USA
ST Equipment & Technology LLC (STET) ti ni idagbasoke a aramada processing eto da lori tribo-electrostatic igbanu Iyapa ti o pese awọn ni erupe ile processing ile ise a ọna lati beneficiate itanran ohun elo pẹlu ohun agbara-daradara ati ki o šee igbọkanle gbẹ ọna. In contrast to other electrostatic separation processes that are typically limited to particles >75μm ni iwọn, awọn STET triboelectric igbanu separator ti wa ni ti baamu fun Iyapa ti gidigidi itanran (<1μm) to niwọntunwọsi isokuso (500μm) patikulu, pẹlu ṣiṣe giga pupọ. The STET tribo-electrostatic technology has been used to process and commercially separate a wide range of industrial minerals and other dry granular powders. Nibi, bench-scale results are presented on the beneficiation of low-grade Fe ore fines using STET belt separation process. Bench-scale testing demonstrated the capability of the STET technology to simultaneously recover Fe and reject SiO2 from itabirite ore with a D50 of 60µm and ultrafine Fe ore tailings with a D50 of 20µm. The STET technology is presented as an alternative to beneficiate Fe ore fines that could not be successfully treated via traditional flowsheet circuits due to their granulometry and mineralogy.
Irin irin ni kẹrin wọpọ ano ni ilẹ ayé ká erunrun [1]. Iron ni awọn ibaraẹnisọrọ to, irin ẹrọ ki o si nitorina ẹya awọn ibaraẹnisọrọ ohun elo ti fun agbaye aje idagbasoke [1-2]. Iron ti wa ni tun gbajumo ni lilo ni ikole ati awọn ẹrọ ti awọn ọkọ [3]. Julọ ti irin irin oro ti wa ni kq ti metamorphosed fi ọjá irin formations (BIF) ninu eyi ti iron ti wa ni commonly ri ni awọn fọọmu ti oxides, hydroxides ati ki o si a kere iye carbonates [4-5]. A pato Iru ti irin formations pẹlu ti o ga kaboneti akoonu ti o wa dolomitic itabirites eyi ti o wa kan ti ọja ti awọn dolomitization ati metamorphism ti BIF idogo [6]. Awọn ti irin irin idogo ninu aye le ti wa ni ri ni Australia, China, Canada, Ukraine, India ati Brazil [5].
Awọn kemikali tiwqn ti irin ores ni o ni ohun kedere jakejado ibiti o ni kemikali tiwqn paapa fun Fe akoonu ati nkan gangue ohun alumọni [1]. Major iron ohun alumọni ni nkan ṣe pẹlu julọ ninu awọn irin ores wa ni hematite, goethite, limonite ati magnetite [1,5]. Awọn ifilelẹ ti awọn contaminants ni iron ores ni o wa SiO2 ati Al2O3 [1,5,7]. Awọn aṣoju yanrin ati alumina ti nso ohun alumọni bayi ni iron ores ni o wa kuotisi, kaolinite, gibbsite, diaspore ati corundum. Ti awọn wọnyi ti o ti wa ni igba woye wipe kuotisi ni awọn tumosi yanrin ti nso ni erupe ile ati kaolinite ati gibbsite ni o wa ni meji-akọkọ alumina ti nso ohun alumọni [7].
Irin irin isediwon wa ni o kun ošišẹ ti nipasẹ ìmọ ọfin iwakusa mosi, Abajade ni significant tailings iran [2]. Awọn irin irin gbóògì eto maa je meta ni asiko: iwakusa, processing ati pelletizing akitiyan. ti awọn wọnyi, processing idaniloju wipe ohun deedee irin ite ati kemistri ti waye saju si pelletizing ipele. Processing pẹlu crushing, classification, milling ati fojusi ifojusi ni jijẹ iron akoonu nigba ti atehinwa iye ti gangue ohun alumọni [1-2]. Kọọkan ni erupe ile idogo ni o ni awọn oniwe-ara oto abuda pẹlu ọwọ lati irin, ati gangue ti nso ohun alumọni, ati nitorina o nilo kan ti o yatọ fojusi ilana [7].
Se Iyapa wa ni ojo melo lo ninu awọn beneficiation ti ga ite irin ores ibi ti awọn ako iron ohun alumọni ni o wa ferro ati paramagnetic [1,5]. Tutu ati ki o gbẹ kekere-kikankikan se Iyapa (LIMS) imuposi ti wa ni lo lati ilana ores pẹlu lagbara se ini bi magnetite nigba ti tutu ga-kikankikan se Iyapa ti lo lati pàla awọn Fe-ti nso ohun alumọni pẹlu lagbara se ini gẹgẹ bi awọn hematite lati gangue ohun alumọni. Iron ores iru goethite ati limonite ti wa ni commonly ri ni tailings ati ki o ko ya gidigidi daradara nipa boya ilana [1,5]. Se awọn ọna bayi italaya ni awọn ofin ti won kekere agbara ati ni awọn ofin ti awọn ibeere fun awọn irin irin lati wa ni ifaragba si se aaye [5].
Flotation, ti a ba tun wo lo, ti lo lati din awọn akoonu ti impurities ni kekere-ite iron ores [1-2,5]. Iron ores le ti wa ni ogidi boya nipa taara anionic flotation ti irin oxides tabi ẹnjinia cationic flotation ti yanrin, sibẹsibẹ ẹnjinia cationic flotation si maa wa ni julọ gbajumo flotation ipa lo ninu awọn iron ile ise [5,7]. Awọn lilo ti flotation awọn oniwe-ni opin nipa awọn iye owo ti reagents, niwaju ti yanrin ati alumina-ọlọrọ slimes ati niwaju kaboneti ohun alumọni [7-8]. Jubẹlọ, flotation nilo egbin omi itoju ati awọn lilo ti ibosile dewatering fun gbẹ ase ohun elo [1].
Awọn lilo ti flotation fun awọn fojusi ti iron tun je desliming bi lilefoofo ni niwaju itanran esi ni din ku ṣiṣe ati ki o ga reagent owo [5,7]. Desliming jẹ paapa lominu ni fun awọn yiyọ ti alumina bi awọn Iyapa ti gibbsite lati hematite tabi goethite nipa eyikeyi dada-lọwọ òjíṣẹ jẹ ohun soro [7]. Julọ ti alumina ara alumọni ba waye ninu awọn finer iwọn ibiti o (<20um) allowing for its removal through desliming. ìwò, a high concentration of fines (<20um) and alumina increases the required cationic collector dose and decreases selectivity dramatically [5,7].
Jubẹlọ, the presence of carbonate minerals – such as in dolomitic itabirites- can also deteriorate flotation selectivity between iron minerals and quartz as iron ores containing carbonates such as dolomite do not float very selectively. Dissolved carbonates species adsorb on the quartz surfaces harming the selectivity of flotation [8]. Flotation can be reasonably effective in upgrading low-grade iron ores, but it is strongly dependent on the ore mineralogy [1-3,5]. Flotation of iron ores containing high alumina content will be possible via desliming at the expense of the overall iron recovery [7], while flotation of iron ores containing carbonate minerals will be challenging and possibly not feasible [8].
Modern processing circuits of Fe-bearing minerals may include both flotation and magnetic concentration steps [1,5]. Fun apẹẹrẹ, magnetic concentration can be used on the fines stream from the desliming stage prior to flotation and on the flotation rejects. The incorporation of low and high intensity magnetic concentrators allows for an increase in the overall iron recovery in the processing circuit by recovering a fraction of the ferro and paramagnetic iron minerals such as magnetite and hematite [1]. Goethite is typically the main component of many iron plant reject streams due to its weak magnetic properties [9]. In the absence of further downstream processing for the reject streams from magnetic concentration and flotation, the fine rejects will end up disposed in a tailings dam [2]. Tailings disposal and processing have become crucial for environmental preservation and recovery of iron valuables, lẹsẹsẹ, and therefore the processing of iron ore tailings in the mining industry has grown in importance [10].
Clearly, the processing of tailings from traditional iron beneficiation circuits and the processing of dolomitic itabirite is challenging via traditional desliming-flotation-magnetic concentration flowsheets due to their mineralogy and granulometry, and therefore alternative beneficiation technologies such as tribo-electrostatic separation which is less restrictive in terms of the ore mineralogy and that allows for the processing of fines may be of interest.
Tribo-electrostatic Iyapa lilo itanna idiyele iyato laarin awọn ohun elo yi ni dada olubasọrọ tabi triboelectric gbigba agbara. Ni simplistic ona, nigbati meji elo ni o wa ni olubasọrọ, the material with a higher affinity for electron gains electrons thus charges negative, nigba ti awọn ohun elo ti pẹlu kekere itanna ijora agbara idiyele rere. Gege bi ofin, low-grade iron ore fines and dolomitic itabirites that are not processable by means of conventional flotation and/or magnetic separation could be upgraded by exploiting the differential charging property of their minerals [11].
Here we present STET tribo-electrostatic belt separation as a possible beneficiation route to concentrate ultrafine iron ore tailings and to beneficiate dolomitic itabirite mineral. The STET process provides the mineral processing industry with a unique water-free capability to process dry feed. The environmentally friendly process can eliminate the need for wet processing, downstream waste water treatment and required drying of final material. Ni afikun, Awọn STET ilana nilo kekere ami-itọju ti awọn erupe ile ati ki o nṣiṣẹ ni ga agbara - soke si 40 ohun orin fun wakati kan. Agbara agbara jẹ kere ju 2 monamona-wakati fun pupọ ti awọn ohun elo ti ni ilọsiwaju.
ohun elo
Meji itanran kekere-ite iron ores won lo ni yi jara ti igbeyewo. Ni igba akọkọ ti irin je ti ohun ultrafine Fe irin tailings ayẹwo pẹlu kan D50 ti 20 μm ati awọn keji ayẹwo ti ẹya itabirite irin irin ayẹwo pẹlu kan D50 ti 60 μm. Mejeeji ayẹwo bayi italaya nigba won beneficiation ati ki o le wa ko le daradara ni ilọsiwaju nipasẹ ibile desliming-flotation-se fojusi iyika nitori won granulometry ati mineralogy. Mejeeji ayẹwo ni won gba lati iwakusa mosi ni Brazil.
Ni igba akọkọ ti sample ti a gba lati ohun ti wa tẹlẹ desliming-flotation-se fojusi Circuit. Awọn ayẹwo ti a gba lati a tailings idido, ki o si dahùn o, homogenized ati ki o sere. Awọn keji ayẹwo jẹ lati ẹya itabirite irin Ibiyi ni Brazil. Awọn ayẹwo ti a itemole ati lẹsẹsẹ nipasẹ iwọn ati awọn itanran ida gba lati awọn classification ipele nigbamii lọ orisirisi awọn ipo ti desliming titi a D98 ti 150 μm ti a waye. Awọn ayẹwo ti a ki o si dahùn o, homogenized ati ki o sere.
Patiku iwọn pinpin (PSD) ni won pinnu lilo a lesa tite imole patiku iwọn itu si wẹwẹ, a Malvern ká Mastersizer 3000 E. Mejeeji ayẹwo ni won tun characterized nipa Loss-on-iginisonu(OFIN), XRF ati XRD. Awọn isonu on iginisonu (OFIN) a ti pinnu nipa gbigbe 4 giramu ti awọn ayẹwo ni a 1000 ºC ileru fun 60 iṣẹju ati riroyin awọn LOI lori ohun ti o gbà igba. Awọn kemikali tiwqn onínọmbà a pari lilo a wefulenti dispersive X-ray filoresenti (WD-XRF) irinse ati awọn ifilelẹ ti okuta ifarahan won yẹwo nipa XRD ilana.
Awọn kemikali tiwqn ati LOI fun awọn tailings ayẹwo (Tailings), ati fun awọn itabirite iron Ibiyi ayẹwo (Itabirite), ti han ni Table 1 ati patiku iwọn pinpin fun awọn mejeeji ayẹwo ti wa ni han ni Ọpọtọ 1. Fun awọn tailings awọn ayẹwo awọn ifilelẹ ti awọn Fe recoverable awọn ifarahan ni o wa goethite ati hematite, ati awọn ifilelẹ ti gangue ni erupe ile ni kuotisi (eeya 4). Fun awọn itabirite ayẹwo awọn ifilelẹ ti awọn Fe recoverable awọn ifarahan ni o wa hematite, ati awọn ifilelẹ ti gangue ohun alumọni ni o wa kuotisi ati dolomite (eeya 4).
Table 1. Abajade ti kemikali onínọmbà fun pataki eroja ni tailings ati Itabirite awọn ayẹwo.
| ayẹwo | Grade (wt%) | |||||||
|---|---|---|---|---|---|---|---|---|
| Fe | SiO2 | Al2O3 | MnO | MgO | cao | LOI** | Others | |
| Tailings | 30.3 | 47.4 | 4.3 | 1.0 | * | * | 3.4 | 13.4 |
| Itabirite | 47.6 | 23.0 | 0.7 | 0.2 | 1.5 | 2.2 | 4.0 | 21.0 |
Patiku Iwon pinpin
awọn ọna
A jara ti adanwo won a še lati se iwadi ni ipa ti o yatọ si sile lori irin ronu ni awọn mejeeji iron ayẹwo lilo STET kikan tribo-electrostatic igbanu separator ọna ẹrọ. Adanwo ti won waiye lilo a ibujoko-asekale tribo-electrostatic igbanu separator, hereafter tọka bi 'benchtop separator'. Ibujoko-asekale igbeyewo ni akọkọ alakoso kan mẹta-alakoso ọna ẹrọ imuse ilana (Wo Table 2) pẹlu ibujoko-asekale imọ, awaoko-asekale igbeyewo ati owo-asekale imuse. Awọn benchtop separator ti lo fun waworan fun eri ti tribo-electrostatic gbigba agbara ati lati mọ ti o ba a awọn ohun elo ti kan ti o dara tani fun electrostatic beneficiation. Awọn ifilelẹ ti awọn iyato laarin kọọkan nkan ti awọn ẹrọ ti wa ni gbekalẹ ni Table 2. Nigba ti awọn ẹrọ ti a lo laarin kọọkan alakoso yato si ni iwọn, ni isẹ opo ni taa kanna.
Table 2. Mẹta-alakoso imuse ilana lilo STET tribo-electrostatic igbanu separator ọna ẹrọ
| Phase | Used for: | Electrode Dimensions (W x L) cm | Type of Process/ |
|---|---|---|---|
| Bench Scale Evaluation | Qualitative Evaluation | 5*250 | Batch |
| Pilot Scale igbeyewo | Quantitative Evaluation | 15*610 | Batch |
| owo Scale Implementation | owo Production | 107 *610 | Continuous |
STET Isẹ Ilana
Ni isẹ opo ti separator gbekele lori tribo-electrostatic gbigba agbara. Ni awọn tribo-electrostatic igbanu separator (isiro 2 ati 3), awọn ohun elo ti ni je sinu dín aafo 0.9 - 1.5 cm laarin awọn meji ni afiwe ipele amọna. Awọn patikulu ti wa ni triboelectrically gba agbara nipasẹ interparticle olubasọrọ. Awọn daadaa agbara ni erupe(s) ati awọn odi agbara ni erupe(s) wa ni ifojusi lati idakeji amọna. Inu awọn separator patikulu ti wa ni gbo soke nipa a lemọlemọfún gbigbe ìmọ-apapo igbanu ati ki o mu ni idakeji itọnisọna. Awọn igbanu ti wa ni fi ṣe ṣiṣu awọn ohun elo ti ati ki o rare awọn awon patikulu nitosi si kọọkan elekiturodu si idakeji opin ti awọn separator. Awọn counter lọwọlọwọ sisan ti awọn yiya sọtọ patikulu ati titilai triboelectric gbigba agbara nipa patiku-patiku collisions pese fun a multistage Iyapa ati awọn esi ni o tayọ ti nw ati gbigba ni a nikan-kọja kuro. Awọn triboelectric igbanu separator ọna ẹrọ ti a ti lo lati ya a jakejado ibiti o ti ohun elo pẹlu apapo ti glassy aluminosilicates / erogba (fly eeru), calcite / kuotisi, talc / magnesite, ati barite / kuotisi.
ìwò, awọn separator oniru jẹ jo o rọrun pẹlu awọn igbanu ati ki o somọ rollers bi awọn nikan gbigbe awọn ẹya ara. Awọn amọna wa ni adaduro ati ki o kq ti ẹya bojumu o tọ awọn ohun elo ti. Awọn separator elekiturodu ipari ni to 6 mita (20 ft.) ati awọn iwọn 1.25 mita (4 ft.) fun iwọn ni kikun ti owo sipo. Awọn ga igbanu iyara kí gidigidi ga throughputs, soke to 40 toonu fun wakati kan fun iwọn ni kikun ti owo sipo. Awọn agbara agbara jẹ kere ju 2 monamona-wakati fun pupọ ti awọn ohun elo ti ni ilọsiwaju pẹlu julọ ninu awọn agbara run nipa meji Motors iwakọ ni igbanu.
Sikematiki ti triboelectric igbanu separator
Apejuwe awọn ti Iyapa ibi
Bi le ti wa ni ti ri ninu Table 2, awọn ifilelẹ ti awọn iyato laarin awọn benchtop separator ati awaoko-asekale ati owo-asekale separators ni wipe awọn ipari ti awọn benchtop separator jẹ to 0.4 igba awọn ipari ti awaoko-asekale ati owo-asekale sipo. Bi awọn separator ṣiṣe ni a iṣẹ ti awọn elekiturodu ipari, ibujoko-asekale igbeyewo ko le ṣee lo bi aropo fun awaoko-asekale igbeyewo. Pilot-asekale igbeyewo ni pataki lati mọ awọn iye ti awọn Iyapa ti awọn STET ilana le se aseyori, ati lati mọ ti o ba STET ilana le pade awọn ọja fojusi labẹ fun kikọ awọn ošuwọn. dipo, awọn benchtop separator ti lo lati ṣe akoso jade tani ohun elo ti o wa ni išẹlẹ ti lati fi eyikeyi significant Iyapa ni awaoko-asekale ipele. Results gba lori ibujoko-asekale yoo wa ni ti kii-iṣapeye, ati awọn Iyapa šakiyesi jẹ kere ju eyi ti yoo wa ni šakiyesi lori kan ti owo won STET separator.
Igbeyewo ni awaoko ọgbin jẹ pataki saju si owo asekale imuṣiṣẹ, sibẹsibẹ, igbeyewo ni ibujoko-asekale ti wa ni iwuri bi akọkọ alakoso awọn imuse ilana fun eyikeyi fi fun awọn ohun elo ti. pẹlupẹlu, ni igba ni eyi ti awọn ohun elo ti wiwa ni opin, awọn benchtop separator pese a wulo ọpa fun awọn waworan ti o pọju aseyori ise agbese (i.e., ise agbese ninu eyi ti onibara ati ise didara fojusi le wa ni pade lilo STET ọna).
Ibujoko-asekale igbeyewo
Standard ilana idanwo a ṣe ni ayika kan pato ìlépa lati mu Fe fojusi ati lati din awọn fojusi ti gangue ohun alumọni. O yatọ si oniyipada won waidi lati mu iwọn iron ronu ati lati mọ awọn itọsọna ti ronu ti o yatọ si awọn ohun alumọni. Awọn itọsọna ti ronu woye nigba benchtop igbeyewo ni ti itọkasi ti awọn itọsọna ti ronu ni awaoko ọgbin ati owo asekale.
Àwọn ayípadà yẹwo to wa ojulumo ọriniinitutu (RH), otutu, elekiturodu polarity, igbanu iyara ati loo foliteji. ti awọn wọnyi, RH ati otutu nikan le ni kan ti o tobi ipa lori iyato tribo-gbigba agbara ati Nitorina on Iyapa awọn esi. nibi, iṣẹ RH ati otutu awọn ipo ni won pinnu ṣaaju ki o to oluwadi ni ipa ti awọn ti o ku oniyipada. Meji polarity awọn ipele won waidi: i) oke elekiturodu polarity rere ati ii) oke elekiturodu polarity negative. Fun awọn STET separator, labẹ a fi fun polarity akanṣe ati labẹ iṣẹ ni RH ati awọn iwọn otutu awọn ipo, igbanu iyara ni jc Iṣakoso mu awọn fun silẹ ọja ite ati ibi-recovery. Igbeyewo lori ibujoko separator iranlọwọ ta imọlẹ lori awọn ipa ti awọn operational oniyipada on tribo-electrostatic gbigba agbara fun a fi fun ni erupe ile awọn ayẹwo, ati nitorina gba awọn esi ati awọn lominu le ṣee lo, si awọn ìyí, lati dín si isalẹ awọn nọmba ti àwọn ayípadà ati adanwo to wa ni ošišẹ ti ni awaoko ọgbin asekale. Table 3 awọn akojọ ti awọn ibiti o ti Iyapa ipo lo bi ara ti alakoso 1 igbelewọn ilana fun awọn tailings ati itabirite awọn ayẹwo.
Table 3 awọn akojọ ti awọn ibiti o ti Iyapa ipo
| Parameter | Units | Range of Values | |
|---|---|---|---|
| Tailings | Itabirite | ||
| Top Electrode Polarity | - | Positive- Negative | Positive- Negative |
| Electrode Voltage | -kV/+kV | 4-5 | 4-5 |
| Feed Relative Humidity (RH) | % | 1-30.7 | 2-39.6 |
| Feed Temperature | ° F (° C) | 71-90 (21.7-32.2) | 70-87 (21.1-30.6) |
| Belt Speed | Fps (m / s) | 10-45 (3.0-13.7) | 10-45 (3.0-13.7) |
| Electrode Gap | Inches (mm) | 0.400 (10.2 mm) | 0.400 (10.2 mm) |
Igbeyewo won waiye lori awọn benchtop separator labẹ ipele ipo, pẹlu kikọ sii ayẹwo ti 1.5 lbs. igbeyewo. A danu run lilo 1 lb. ti awọn ohun elo ti a ṣe ni laarin igbeyewo lati rii daju wipe eyikeyi ti ṣee ṣe carryover ipa lati išaaju majemu ti a ko kà. Ṣaaju ki o to igbeyewo ti a bere ohun elo ti o wà homogenized ati awọn ayẹwo awọn baagi ti o ni awọn mejeeji run ati ki o danu awọn ohun elo ti won ti pese sile. Ni ibere ti kọọkan ṣàdánwò awọn iwọn otutu ati ojulumo ọriniinitutu (RH) ti a won lilo a Vaisala HM41 ọwọ-waye ọriniinitutu ati otutu ibere. Awọn ibiti o ti otutu ati RH kọja gbogbo adanwo wà 70-90 ° F (21.1-32.2 (° C) ati 1-39.6%, lẹsẹsẹ. Lati se idanwo kekere kan RH ati / tabi ti o ga otutu, kikọ sii ki o si danu ayẹwo ni won pa ni a gbigbe lọla ni 100 ° C fun igba laarin 30-60 iṣẹju. Ni ifiwera, ti o ga RH iye ti won seese nipa fifi kekere oye akojo ti omi si awọn ohun elo, atẹle nipa homogenization. Lẹhin ti RH ati otutu ti a won lori kọọkan kikọ awọn ayẹwo, nigbamii ti igbese je lati ṣeto elekiturodu polarity, igbanu iyara ati foliteji si fẹ ipele. Aafo iye won pa ibakan ni 0.4 inches (10.2 mm) nigba ti igbeyewo ipolongo fun awọn tailings ati itabirite awọn ayẹwo.
Šaaju si kọọkan igbeyewo, a kekere kikọ sii iha-ayẹwo ti o ni awọn to 20g ti a gba (ni pataki bi 'Feed'). Lori eto gbogbo isẹ oniyipada, awọn ohun elo ti a ti je sinu benchtop separator lilo ohun ina vibratory atokan nipasẹ awọn aarin ti awọn benchtop separator. Ayẹwo ni won gba ni opin ti kọọkan ṣàdánwò ati awọn ìwọn ti ọja opin 1 (ni pataki bi 'E1') ati ọja opin 2 (ni pataki bi 'E2') ni won pinnu lilo a ofin-fun-isowo kika asekale. Awọn wọnyi kọọkan igbeyewo, kekere iha-ayẹwo ti o ni awọn to 20 g of E1 ati E2 ni won tun gbà. Ibi-Egbin to E1 ati E2 ti wa ni apejuwe nipa:
ibi tiatiE1 ati atiE2 ni o wa ni ibi-Egbin ni to E1 ati E2, lẹsẹsẹ; ati ki o wa awọn ayẹwo òṣuwọn gbà si awọn separator awọn ọja E1 ati E2, lẹsẹsẹ. Fun awọn mejeeji awọn ayẹwo, Fe fojusi a pọ si ọja E2.
Fun kọọkan ṣeto ti iha-ayẹwo (i.e., Feed, E1 ati E2) LOI ati akọkọ oxides tiwqn nipa XRF ti pinnu. Fe2 awọn3 awọn akoonu ti won pinnu lati iye. Fun awọn tailings ayẹwo LOI yoo taara relate si awọn akoonu ti goethite ni awọn ayẹwo bi awọn iṣẹ-hydroxyl awọn ẹgbẹ ni goethite yoo oxidize sinu H2 awọng [10]. ilodi si, fun awọn itabirite ayẹwo LOI yoo taara relate si ni awọn ti carbonates ni awọn ayẹwo, bi kalisiomu ati magnẹsia carbonates yoo decompose sinu wọn akọkọ oxides Abajade ni awọn Tu ti CO2g ki o si iha lesese ayẹwo pipadanu àdánù. XRF ilẹkẹ won ti pese sile nipa dapọ 0.6 giramu ti ni erupe ile awọn ayẹwo pẹlu 5.4 giramu ti litiumu tetraborate, eyi ti a ti yan nitori awọn kemikali tiwqn ti awọn mejeeji tailings ati itabirite awọn ayẹwo. XRF onínọmbà won tobojumu fun LOI.
Níkẹyìn, Fe imularada EFe to ọja (E2) ati SiO2 ijusile Qati won iṣiro. EFe ti wa ni awọn ogorun ti Fe pada ninu awọn koju si wipe ti atilẹba kikọ sii ayẹwo ati Qsio2 ni awọn ogorun ti kuro lati atilẹba kikọ sii ayẹwo. EFe ati Qati ti wa ni ṣàpèjúwe nipasẹ:
ibi ti Ci,(kikọ sii,E1, E2) ni awọn tobojumu fojusi ogorun fun awọn iha-ayẹwo ká i paati (eg., Fe, sio2)
ayẹwo Mineralogy
Awọn XRD Àpẹẹrẹ fifi pataki ni erupe ile awọn ifarahan fun awọn tailings ati itabirite ayẹwo ti wa ni han ni Ọpọtọ 4. Fun awọn tailings awọn ayẹwo awọn ifilelẹ ti awọn Fe recoverable awọn ifarahan ni o wa goethite, hematite ati magnetite, ati awọn ifilelẹ ti gangue ni erupe ile ni kuotisi (eeya 4). Fun awọn itabirite ayẹwo awọn ifilelẹ ti awọn Fe recoverable awọn ifarahan ni o wa hematite ati magnetite ati awọn ifilelẹ ti gangue ohun alumọni ni o wa kuotisi ati dolomite. Magnetite han ni kakiri awọn ifọkansi ni mejeji awọn ayẹwo. pure hematite, goethite, ati magnetite ni 69.94%, 62.85%, 72.36% Fe, lẹsẹsẹ.
D elo. A - Tailings ayẹwo, B - Itabirite sample
Ibujoko-asekale adanwo
A jara ti igbeyewo gbalaye a ṣe lori kọọkan ni erupe ile awọn ayẹwo Eleto ni mimu Fe ati dinku SiO2 akoonu. Eya ninu fifokansi to E1 ni yio je ti itọkasi ti a odi gbigba agbara ihuwasi nigba ti eya fojusi to E2 to kan rere gbigba agbara ihuwasi. Ti o ga igbanu iyara wà ọjo si awọn processing ti awọn tailings sample; sibẹsibẹ, awọn ipa ti yi ayípadà nikan ti a ri lati wa ni kere significant fun awọn itabirite sample.
Apapọ awọn esi fun awọn tailings ati itabirite ayẹwo ti wa ni gbekalẹ ni Ọpọtọ 5, eyi ti a ti iṣiro lati 6 ati 4 adanwo, lẹsẹsẹ. eeya 5 iloju apapọ ibi-ikore ati kemistri fun kikọ sii ati awọn ọja E1 ati E2. Ni afikun, kọọkan Idite iloju awọn yewo tabi isalẹ ni fojusi (E2- Feed) fun kọọkan ayẹwo paati e.g., Fe, SiO2 Rere iye ti wa ni nkan ṣe si ohun ilosoke ninu fojusi to E2, nigba ti odi iye ti wa ni nkan to kan isalẹ ni fojusi to E2.
Fig.5. Apapọ ibi-Egbin ni ati kemistri fun Feed, E1 ati E2 awọn ọja. Aṣiṣe ifi soju 95% igbekele arin.
Fun awọn tailings ayẹwo Fe akoonu ti a pọ lati 29.89% to 53.75%, lori apapọ, ni a ibi-ikore atiE2 - tabi agbaye ibi-recovery – ti 23.30%. Eleyi ni ibamu si Fe imularada ( ati yanrin ijusile (QE2 ) iye ti 44.17% ati 95.44%, lẹsẹsẹ. Awọn LOI akoonu ti a pọ lati 3.66% to 5.62% eyi ti o tọkasi wipe ilosoke ninu Fe akoonu ti wa ni jẹmọ si ilosoke ninu goethite akoonu (eeya 5).
Fun awọn itabirite ayẹwo Fe akoonu ti a pọ lati 47.68% to 57.62%, lori apapọ, ni a ibi-ikore atiE2 -ti 65.0%. Eleyi ni ibamu si Fe imularada EFe( ati yanrin ijusile (Qsio2) iye ti 82.95% ati 86.53%, lẹsẹsẹ. The LOI, MgO ati cao awọn akoonu ti won pọ lati 4.06% to 5.72%, 1.46 to 1.87% ati lati 2.21 to 3.16%, lẹsẹsẹ, eyi ti o tọkasi wipe dolomite ti wa ni gbigbe ni kanna itọsọna bi Fe-ara ohun alumọni (eeya 5).
Fun awọn mejeeji awọn ayẹwo,AL2 awọn3 , MnO ati P dabi lati wa ni gbigba agbara ni kanna itọsọna bi Fe-ara ohun alumọni (eeya 5). Nigba ti o ti wa ni fẹ lati dinku awọn fojusi ninu awọn mẹta eya, awọn ni idapo fojusi ti SiO2, AL2 , awọn3 , atiE2 MnO ati P ti wa ni dinku fun awọn mejeeji ayẹwo, ati nitori awọn lapapọ ipa waye nipa lilo awọn benchtop separator jẹ ẹya ẹya ninu awọn ọja Fe ite ati a isalẹ ninu awọn contaminants fojusi.
ìwò, benchtop HIV afihan eri ti o munadoko gbigba agbara ati Iyapa ti irin àti yanrin awon patikulu. The si seleri yàrá asekale esi daba wipe asewo asekale igbeyewo pẹlu akọkọ ati keji koja yẹ ki o wa ni ošišẹ ti.
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Esiperimenta data ni imọran wipe awọn STET separator yorisi ni ohun pataki ilosoke ninu Fe akoonu nigba ti nigbakannaa atehinwa SiO2 akoonu.
Lehin afihan wipe triboelectrostatic Iyapa le ja si ni a significant ilosoke ninu Fe akoonu, a fanfa lori lami ti awọn esi ti, on awọn ti o pọju achievable Fe awọn akoonu ati lori awọn kikọ awọn ibeere ti awọn ọna ti wa ni ti nilo.
Lati bẹrẹ, o jẹ pataki lati jiroro ni gbangba, gbigba agbara ihuwasi ti ni erupe ile eya ni mejeji ayẹwo. Fun awọn tailings awọn ayẹwo awọn ifilelẹ ti awọn irinše wà Fe oxides ati kuotisi ati esiperimenta awọn esi afihan wipe Fe oxides ogidi to E2 nigba ti kuotisi ogidi to E1. Ni simplistic ona, o le wa ni wi pe Fe afẹfẹ patikulu ipasẹ kan rere idiyele ati awọn ti o kuotisi patikulu ipasẹ kan odi idiyele. Yi ihuwasi jẹ ibamu pẹlu awọn triboelectrostatic iseda ti awọn mejeeji ohun alumọni bi han nipa Ferguson (2010) [12]. Table 4 fihan kedere triboelectric jara fun ti yan ohun alumọni da lori inductive Iyapa, ati awọn ti o fihan wipe kuotisi wa ni be ni isalẹ ti gbigba agbara jara nigba ti goethite, magnetite ati hematite ti wa ni be ti o ga soke ni awọn jara. Awọn ohun alumọni ni awọn oke ti awọn jara yoo ṣọ lati gba agbara si rere, nigba ti awọn ohun alumọni ni isalẹ yoo ṣọ lati gba a odi idiyele.
Ti a ba tun wo lo, fun awọn itabirite ayẹwo awọn ifilelẹ ti awọn irinše wà hematite, kuotisi ati dolomite ati esiperimenta esi fihan wipe Fe oxides ati dolomite ogidi to E2 nigba ti kuotisi ogidi to E1. Eleyi tọkasi wipe hematite patikulu ati dolomite ipasẹ kan rere idiyele nigba ti kuotisi patikulu ipasẹ kan odi idiyele. Bi le ti wa ni ti ri ninu Table 4, carbonates ti wa ni be ni oke ti awọn tribo-electrostatic jara, eyi ti o tọkasi wipe kaboneti patikulu ṣọ lati gba a rere idiyele, ati ni Nitori lati wa ni ogidi to E2. Mejeeji dolomite ati hematite won ogidi ni kanna itọsọna, o nfihan pe awọn ìwò ipa fun hematite patikulu niwaju kuotisi ati dolomite je lati gba a rere idiyele.
Awọn itọsọna ti ronu ti mineralogical eya ni kọọkan ayẹwo jẹ ti awọn julọ anfani, bi o ti yoo mọ awọn ti o pọju achievable Fe ite ti o le wa ni gba nipa ọna ti a nikan kọja lilo awọn tribo-electrostatic igbanu separator ọna ẹrọ.
Fun awọn tailings ati itabirite ayẹwo awọn ti o pọju achievable Fe akoonu yoo wa ni ṣiṣe nipasẹ ifosiwewe meta: i) Iye ti Fe ni Fe-ara ohun alumọni; ii) awọn kere kuotisi (SiO2 ) akoonu ti le waye ati; iii) Awọn nọmba ti contaminants gbigbe ni kanna itọsọna bi Fe-ara ohun alumọni. Fun awọn tailings awọn ayẹwo awọn ifilelẹ ti awọn contaminants gbigbe ni kanna itọsọna ti Fe-ti nso ohun alumọni ni o wa Al2 awọn3 MnO ti nso ohun alumọni, nigba ti fun awọn itabirite ayẹwo awọn ifilelẹ ti awọn contaminants ni o wa cao MgO Al2 awọn3 ti nso ohun alumọni.
| Mineral Name | Charge acquired (apparent) |
|---|---|
| Apatite | +++++++ |
| Carbonates | ++++ |
| Monazite | ++++ |
| Titanomagnetite | . |
| Ilmenite | . |
| Rutile | . |
| Leucoxene | . |
| Magnetite/hematite | . |
| Spinels | . |
| Garnet | . |
| Staurolite | - |
| Altered ilmenite | - |
| Goethite | - |
| Zircon | -- |
| Epidote | -- |
| Tremolite | -- |
| Hydrous silicates | -- |
| Aluminosilicates | -- |
| Tourmaline | -- |
| Actinolite | -- |
| Pyroxene | --- |
| Titanite | ---- |
| Feldspar | ---- |
| kuotisi | ------- |
Table 4. Kedere triboelectric jara fun ti yan ohun alumọni da lori inductive Iyapa. Títúnṣe lati D.N Ferguson (2010) [12].
Fun awọn tailings ayẹwo, awọn Fe akoonu ti a won ni 29.89%. XRD data tọkasi wipe predominant alakoso ni goethite, atẹle nipa hematite, ati nitori awọn ti o pọju achievable Fe akoonu ti o ba ti kan ti o mọ Iyapa si wà ṣee ṣe ni yio jẹ laarin 62.85% ati 69.94% (eyi ti o wa ni Fe akoonu ti ti funfun goethite ati hematite, lẹsẹsẹ). bayi, kan ti o mọ Iyapa ni ko ṣee ṣe bi Al2, awọn3 MnO ati P-ti nso ohun alumọni ti wa ni gbigbe ni kanna itọsọna bi awọn Fe-ti nso ohun alumọni, ki o si nitorina eyikeyi ilosoke ninu Fe akoonu yoo tun ja si ni ohun ilosoke ti awọn wọnyi contaminants. ki o si, lati mu awọn Fe akoonu, iye ti kuotisi to E2 yoo nilo lati wa ni significantly din ku si ojuami ti o offsets awọn ronu ti , MnO ati P to ọja (E2). Bi o han ni Table 4, kuotisi ni o ni kan to lagbara ifarahan lati gba a odi idiyele, ati Nitorina ni awọn isansa ti awọn miiran ohun alumọni nini ohun kedere odi gbigba agbara ihuwasi ti o yoo jẹ ṣee ṣe lati ni riro dinku awọn oniwe-akoonu si ọja (E2) nipa ọna ti a akọkọ kọja lilo awọn triboelectrostatic igbanu separator ọna ẹrọ.
Fun apẹẹrẹ, ti o ba ti a ba ro pe gbogbo awọn Fe akoonu ninu awọn ti tailings ayẹwo ni nkan to goethite (FeO(OH)), ati pe awọn nikan ni gangue oxides ni o wa SiO2, Al2awọn3 ati MnO, ki o si Fe akoonu si ọja yoo wa ni fun nipasẹ:
Fe(%)=(100-SiO2 – (Al2 awọn3 + MnO*0.6285
ibi ti, 0.6285 ni awọn ogorun ti Fe ni funfun goethite. Eq.4 nroyin awọn located siseto ti o gba ibi lati koju Fe bi AL2awọn3 + MnO mu nigba ti SiO2 dinku.
Fun awọn itabirite ayẹwo awọn Fe akoonu ti a won ni 47.68%. XRD data tọkasi wipe predominant alakoso ni hematite ati nitori awọn ti o pọju achievable Fe akoonu ti o ba ti kan ti o mọ Iyapa si wà ṣee ṣe ni yio jẹ sunmo si 69.94% (eyi ti o jẹ ti awọn Fe akoonu ti funfun hematite). Bi o ti sísọ fun awọn tailings awọn ayẹwo kan ti o mọ Iyapa yoo ko ni le ṣee ṣe bi cao, MgO, Al2 awọn3 ti nso ohun alumọni ti wa ni gbigbe ni kanna itọsọna bi hematite, ati nitorina lati mu Fe akoonu SiO2 akoonu gbọdọ wa ni dinku. Ro pe awọn gbogbo ti awọn Fe akoonu ni yi ayẹwo ni nkan to hematite (Fe2awọn3) ati pe awọn nikan oxides ti o wa ninu gangue ohun alumọni ni o wa SiO2, cao, MgO, Al2awọn3 ati MnO; ki o si Fe akoonu ni awọn ọja yoo wa ni fun nipasẹ:
Fe(%)=(100-SiO2-Cao + MgO +Al2awọn3+MnO+OFIN*0.6994
ibi ti, 0.6994 ni awọn ogorun ti Fe ni funfun hematite. O gbodo ti ni woye wipe Eq.5 pẹlu LOI, nigba ti Eq.4 wo ni ko. Fun awọn itabirite sample, awọn LOI ni nkan si niwaju carbonates nigba ti fun awọn tailings ayẹwo ti o ti wa ni nkan to Fe-ti nso ohun alumọni.
daju, fun awọn mejeeji tailings ati itabirite awọn ayẹwo ti o ti ṣee ṣe lati significantly mu Fe akoonu nipa atehinwa awọn akoonu ti SiO2; sibẹsibẹ, bi o han ni Eq.4 ati Eq.5, awọn ti o pọju achievable Fe akoonu yoo wa ni opin nipa awọn itọsọna ti ronu ati awọn fojusi ti oxides nkan to gangue ohun alumọni.
Gege bi ofin, awọn fojusi ti Fe ni mejeji ayẹwo le wa ni siwaju pọ nipa ọna ti a keji kọja lori awọn STET separator ninu eyi ti cao,MgO Al2 awọn3 ati MnOti nso ohun alumọni le wa ni niya lati Fe-ti nso ohun alumọni. Iru Iyapa ni yio jẹ ṣee ṣe ti o ba ti julọ ti kuotisi ni awọn ayẹwo ti a kuro nigba kan akọkọ kọja. Ni awọn isansa ti kuotisi, diẹ ninu awọn ti awọn ti o ku gangue ohun alumọni yẹ ni yii idiyele ni idakeji ti goethite, hematite ati magnetite, eyi ti yoo ja si ni pọ si Fe akoonu. Fun apẹẹrẹ, fun awọn itabirite ayẹwo ati orisun ni awọn ipo ti dolomite ati hematite ni triboelectrostatic jara (Wo Table 4), dolomite / hematite Iyapa yẹ ki o jẹ ti ṣee ṣe bi dolomite ni o ni kan to lagbara ifarahan lati gba agbara si rere ni ibatan si hematite.
Lehin sísọ lori awọn ti o pọju achievable Fe akoonu ti a fanfa lori awọn kikọ awọn ibeere fun awọn ọna ti wa ni ti nilo. Awọn STET tribo-electrostatic igbanu separator nbeere kikọ sii awọn ohun elo ti lati wa ni gbẹ ati ki o finely ilẹ. Gan kekere oye ti ọrinrin le ni kan ti o tobi ipa lori iyato tribo-gbigba agbara ati nitori awọn kikọ sii ọrinrin yẹ ki o wa din ku to <0.5 wt.%. Ni afikun, the feed material should be ground sufficiently fine to liberate gangue materials and should be at least 100% passing mesh 30 (600 um). At least for the tailings sample, the material would have to be dewatered followed by a thermal drying stage, while for the itabirite sample grinding coupled with, or follow by, thermal drying would be necessary prior to beneficiation with the STET separator.
The tailings sample was obtained from an existing desliming-flotation-magnetic concentration circuit and collected directly from a tailings dam. Typical paste moistures from tailings should be around 20-30% and therefore the tailings would need to be dried by means of liquid-solid separation (dewatering) followed by thermal drying and deagglomeration. The use of mechanical dewatering prior to drying is encouraged as mechanical methods have relative low energy consumption per unit of liquid removed in comparison to thermal methods. About 9.05 Btu are required per pound of water eliminated by means of filtration while thermal drying, ti a ba tun wo lo, requires around 1800 Btu per pound of water evaporated [13]. The costs associated with the processing of iron tailings will ultimately depend on the minimum achievable moisture during dewatering and on the energetic costs associated with drying.
The itabirite sample was obtained directly from an itabirite iron formation and therefore to process this sample the material would need to undergo crushing and milling followed by thermal drying and deagglomeration. One possible option is the use of hot air swept roller mills, in which dual grinding and drying could be achieved in a single step. The costs associated with the processing of itabirite ore will depend on the feed moisture, feed granulometry and on the energetic costs associated to milling and drying.
For both samples deagglomeration is necessary after the material have been dried to ensure particles are liberated from one another. Deagglomeration can be performed in conjunction to the thermal drying stage, allowing for efficient heat transfer and energy savings.
Ibujoko-asekale esi gbekalẹ nibi afihan lagbara eri ti gbigba agbara ati Iyapa ti Fe-ara awọn ohun alumọni lati kuotisi lilo triboelectrostatic igbanu Iyapa.
Fun awọn tailings ayẹwo Fe akoonu ti a pọ lati 29.89% to 53.75%, lori apapọ, ni a ibi-ikore ti 23.30%, eyi ti ni ibamu si Fe imularada ati yanrin ijusile iye ti 44.17% ati 95.44%, lẹsẹsẹ. Fun awọn itabirite ayẹwo Fe akoonu ti a pọ lati 47.68 % to 57.62%, lori apapọ, ni a ibi-ikore ti 65.0%, eyi ti ni ibamu si Fe imularada ati yanrin ijusile iye ti 82.95% ati 86.53%, lẹsẹsẹ. Awọn wọnyi ni esi ti won pari lori kan separator ti o jẹ kere ati ki o kere daradara ju awọn STET ti owo separator.
Esiperimenta awari fihan pe fun awọn mejeeji tailings ati itabirite ayẹwo awọn ti o pọju achievable Fe akoonu yoo dale lori awọn kere achievable kuotisi akoonu. Ni afikun, iyọrisi ti o ga Fe onipò le jẹ ṣee ṣe nipa ọna ti a keji kọja lori STET igbanu separator.
Awọn esi ti iwadi yi afihan wipe-kekere ite irin irin itanran le wa ni igbegasoke nipasẹ ọna ti STET tribo-electrostatic igbanu separator. Siwaju ise ni awaoko ọgbin asekale ti wa ni niyanju lati mọ awọn iron koju ite ati imularada ti le waye. Da lori iriri, awọn ọja imularada ati / tabi awọn ite yoo significantly mu ni asewo asekale processing, bi akawe si ibujoko-asekale igbeyewo ẹrọ nlo nigba wọnyi irin irin idanwo. Awọn STET tribo-electrostatic Iyapa ilana le pese significant anfani lori mora processing ọna fun irin irin itanran.
