Khetha ulimi:
Lucas Rojas Mendoza, ST Izinsiza kusebenza & ubuchwepheshe, USA
lrojasmendoza@steqtech.com
Frank Hrach, ST Izinsiza kusebenza & ubuchwepheshe, USA
Kyle Flynn, ST Izinsiza kusebenza & ubuchwepheshe, USA
Abhishek Gupta, ST Izinsiza kusebenza & ubuchwepheshe, USA
ST Izinsiza kusebenza & ubuchwepheshe LLC (STET) uye wazakhela inoveli ukuhlelwa uhlelo esekelwe tribo-electrostatic ibhande ngokwahlukana enikeze nekuhanjiswa umkhakha liyindlela beneficiate izinto enhle kodwa eyongayo futhi yomile ngokuphelele ubuchwepheshe. In contrast to other electrostatic separation processes that are typically limited to particles >75μm ngosayizi, the isihlukanisi STET triboelectric ibhande is ukuhanjwa ukwehlukana esihle kakhulu (<1μm) ukuze ngokulinganisela indawo (500μm) izinhlayiya, nge-throughput ephezulu kakhulu. The STET tribo-electrostatic technology has been used to process and commercially separate a wide range of industrial minerals and other dry granular powders. Lapha, 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.
Nsimbi lesine isici ezivamile e ungqimba lomhlaba [1]. Iron ibalulekile steel yokukhiqiza futhi ngenxa yalokho impahla kubalulekile ekuthuthukiseni umnotho womhlaba wonke [1-2]. Iron nayo kabanzi ukwakhiwa kanye yokukhiqiza izimoto [3]. Iningi nsimbi izinsiza yakhiwa metamorphosed banded zokwakheka yensimbi (BIF) lapho insimbi ngokuvamile atholakala ngendlela oxides, hydroxides futhi ngezinga elincane carbonates [4-5]. A uhlobo oluthile zokwakheka yensimbi nge ephakeme okuqukethwe carbonate kukhona itabirites dolomitic eziwumkhiqizo we dolomitization futhi metamorphism ka BIF ezifakwa [6]. Umhlangano omkhulu kunayo yonke yensimbi nsimbi emhlabeni kungatholakala e-Australia, China, Canada, Ukraine, India ne-Brazil [5].
Ukwakheka kwamakhemikhali yensimbi imikhando ine ezahlukene sobala ububanzi e amakhemikhali ukwakheka ikakhulukazi Fe okuqukethwe futhi ezihambisana gangue amaminerali [1]. Okukhulu yensimbi namaminerali elihlobene ne iningi imikhando nokusansimbi hematite, goethite, limonite futhi magnetite [1,5]. I ezingcolisa lomcoka yensimbi imikhando kukhona SiO2 futhi Al2O3 [1,5,7]. I ejwayelekile Silica futhi alumina eziveza amaminerali atholakala yensimbi imikhando kukhona asebenza ngebhethri, kaolinite, gibbsite, diaspore futhi corundum. Kulezi ngokuvamile baphawula ukuthi asebenza ngebhethri yiyona kusho Silica eziveza amaminerali kanye kaolinite futhi gibbsite kuyizinto ezimbili eziyinhloko alumina nithela amaminerali [7].
Nsimbi isizinda ikakhulukazi latenta asebentisa emgodini ovulekile izimayini nokusebenza, okuholela abalulekile tailings isizukulwane [2]. Uhlelo ukukhiqizwa nsimbi ngokuvamile uhlanganisa izigaba ezintathu: izimayini, ukuqhutshwa kanye pelletizing imisebenzi. kulezi, ukucutshungulwa kucinisekisa kutsi kunebudlelwane ezanele yensimbi grade kanye ne-chemistry kufinyelelwa ngaphambi esigabeni pelletizing. Icubungula kuhlanganisa kwasani, ngezigaba, wokugaya kanye okuhlushwa kuhloswe ngaso okwandisa okuqukethwe yensimbi ngenkathi kuncishiswe inani gangue amaminerali [1-2]. idiphozi ngamunye amaminerali has izici zayo siqu esiyingqayizivele mayelana yensimbi kanye gangue nithela amaminerali, ngakho-ke kudinga ukugxilisa ingqondo indlela ehlukile [7].
Magnetic ngokwahlukana ngokuvamile elisetshenziswa kokuzuza okusezingeni eliphezulu grade yensimbi imikhando lapho evelele yensimbi amaminerali kukhona ferro futhi paramagnetic [1,5]. Wet futhi yomile ongaphakeme-amandla kazibuthe ngokuhlukana (LIMS) amasu asetshenziswa ukucubungula imikhando nge izakhiwo oqinile magnetic ezifana magnetite ngenkathi ezimanzi ephezulu umfutho ngokwahlukana kazibuthe isetshenziswa ukuhlukanisa namaminerali nithela Fe-nge ababuthakathaka izakhiwo kazibuthe ezifana hematite kusuka amaminerali gangue. Iron imikhando goethite okunjalo futhi limonite ngokuvamile atholakala e tailings futhi akusho ukuhlukanisa kahle ngokunye kwalokhu amasu [1,5]. izindlela Magnetic izinselele manje ngokwemigomo ngezikhundla zabo ongaphakeme futhi ngokuya imfuneko ngoba netshe insimbi ekuthonyweni kazibuthe [5].
flotation, Ngokwesinye isandla, isetshenziswa ukuze unciphise okuqukethwe ukungcola ongaphakeme-ebangeni yensimbi imikhando [1-2,5]. Iron imikhando kungenziwa bagxila noma nge ngqo flotation anionic yensimbi oxides noma ukubuyisela emuva flotation cationic of Silica, Nokho ukuhlanekezela flotation cationic uhlala ethandwa kakhulu flotation umzila obusetshenziswa embonini yensimbi [5,7]. Ukusetshenziswa flotation yayo engavimba izindleko reagents, khona Silica futhi alumina-ocebile slimes futhi khona amaminerali carbonate [7-8]. Ngaphezu kwalokho, flotation zidinga ukwelashwa imfucuza amanzi ukusetshenziswa Ukususwa esezansi ngoba ezomile izicelo lokugcina [1].
Ukusetshenziswa flotation ngoba lokuhlushwa yensimbi Kuhilela desliming njengoba sintanta khona inhlawulo imiphumela kahle kwehle futhi okusezingeni eliphezulu reagent izindleko [5,7]. Desliming kuhlaba ezibucayi yokususa alumina njengoba ukwehlukana gibbsite kusukela hematite noma goethite yinoma yimuphi ejenti ebusweni-asebenzayo kunzima ngempela [7]. Iningi alumina eziveza namaminerali kwenzeka ubukhulu zikanokusho ububanzi (<20um) allowing for its removal through desliming. Kukonke, a high concentration of fines (<20um) and alumina increases the required cationic collector dose and decreases selectivity dramatically [5,7].
Ngaphezu kwalokho, 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]. Ngokwesibonelo, 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, ngokulandelana, 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.
ngokuhlukana Tribo-electrostatic isebenzisa kagesi icala umehluko phakathi izinto ezivezwa ebusweni naye noma ukushaja triboelectric. Ngezindlela lolumalula, lapho izinto ezimbili nabo, the material with a higher affinity for electron gains electrons thus charges negative, ngenkathi impahla kanye aphansi electron ziyezwana uyala omuhle. Ngokomthetho, 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. Ngaphezu kwalokho, Inqubo STET kudinga kancane pre-ekwelapheni timbiwa kanye usebenza umthamo high - kuze kufinyelele 40 amathoni ngehora. Ukusetshenziswa kwamandla kagesi lingaphansi kuka 2 kilowatt-amahora sethani ngayinye kusetshenzwe.
Izinto
Amabili esihle ongaphakeme-ebangeni yensimbi imikhando yasetshenziswa kule kokuxilongwa. I-ore lokuqala lalinabashumayeli i ultrafine Fe ore tailings Isampula D50 ka 20 μm kanye isampula yesibili i itabirite nsimbi Isampula D50 ka 60 μm. Bobabili amasampula nezinselele ngesikhathi lokuhlomulisa yabo futhi ayikwazi kahle okwenziwa bendabuko desliming-flotation-magnetic lokuhlushwa izifunda ngenxa granulometry yabo futhi mineralogy. Bobabili amasampula eyatholakala kusukela imisebenzi ezimayini Brazil.
Isampula lokuqala etholwe i okuhlushwa wesifunda ekhona desliming-flotation-magnetic. Isampula kwaba eqoqwe edamini tailings, ke omisiwe, homogenized futhi elinezinto. Isampula lesibili ivela itabirite yensimbi kumiswa e-Brazil. Isampula olwembiza futhi ihlelwa usayizi kanye ingxenyenamba emihle etholakala esigabeni ngezigaba kamuva kwavele izigaba eziningana desliming kuze kube D98 ka 150 μm yafinyelelwa. I isampula ke omisiwe, homogenized futhi elinezinto.
usayizi Particle kukaMoya (PSD) babezimisele usebenzisa laser umumo womsebenzi ubukhulu kuyizinhlayiyana analyzer, a Malvern sika Mastersizer 3000 E. Bobabili amasampula nazo libhekene Ukulahlekelwa-on-ukuthungela(UMTHETHO), XRF futhi XRD. Ukulahlekelwa ku ukuthungela (UMTHETHO) wayezimisele ngokubheja 4 amagremu isampula endaweni 1000 ºC somlilo 60 amaminithi kanye ekubikeni Loi njalo njengoba wathola. Uhlaziyo amakhemikhali ukwakheka yaqedwa usebenzisa wavelength dispersive-X-ray Fluorescence (WD-XRF) ithuluzi kanye crystalline main izigaba abaphenywe ngu XRD amasu.
Ukwakheka zamakhemikhali Loi ngokuba tailings isampula (Tailings), futhi insimbi itabirite kumiswa isampula (Itabirite), siboniswa ethebuleni 1 futhi ubukhulu kuyizinhlayiyana kukaMoya ngoba amasampula kokubili zibonisiwe Kumdwebo 1. Ukuze tailings sampula main Fe izigaba ukuyithola kukhona goethite futhi hematite, futhi main gangue amaminerali kuyinto asebenza ngebhethri (Fig 4). Ukuze isampuli itabirite main Fe izigaba ukuyithola kukhona hematite, futhi main gangue amaminerali kukhona asebenza ngebhethri futhi dolomite (Fig 4).
Ithebula 1. Umphumela ahlukahlukene okuhlaziya amakhemikhali kuzinto ezinkulu e tailings namasampula Itabirite.
| Sample | 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 |
Particle Usayizi Nokwabiwa
izindlela
Uchungechunge ucwaningo ayehloselwe ukuphenya umphumela nemingcele ezahlukene ku yensimbi ukunyakaza amasampula kokubili yensimbi usebenzisa STET nokuphathelene tribo-electrostatic ibhande isihlukanisi ubuchwepheshe. Ukuhlolwa yayiqhutshelwa usebenzisa ebhentshini ukuziphilisa tribo-electrostatic ibhande isihlukanisi, emva kwalokhu esizobizwa ngokuthi 'isihlukanisi benchtop'. ukuhlolwa Bench ukuziphilisa iyona Isigaba sokuqala ezintathu okhombisa ubuchwepheshe ukuqaliswa inqubo (Bona Ithebula 2) kuhlanganise kokuhlaziywa ebhentshini ukuziphilisa, umshayeli isikali sokuhlola nezentengiselwano isikali ukuqaliswa. I isihlukanisi benchtop isetshenziselwa kuthiwa ukuhlolwa kwezinsana ubufakazi ukushaja tribo-electrostatic futhi ukuthola ukuthi ebonakala- olungele i lokuhlomulisa electrostatic. Umahluko omkhulu phakathi emshinini ngamunye ethulwa kuThebula 2. Nakuba imishini esetshenziswa ngaphakathi isigaba ngasinye kuyahluka ngosayizi, isimiso msebenzi ngokuyinhloko okufanayo.
Ithebula 2. Ezintathu okhombisa inqubo usebenzisa STET tribo-electrostatic ibhande isihlukanisi ubuchwepheshe
| Isigaba | Isetshenziselwa: | I-Electrode Dimensions (W x L) cm | Type of Process/ |
|---|---|---|---|
| Bench Scale Evaluation | Qualitative Evaluation | 5*250 | Iqoqo |
| I-Pilot Scale Ukuhlola | Quantitative Evaluation | 15*610 | Iqoqo |
| commercial Scale Implementation | commercial Production | 107 *610 | Okuqhubekayo |
STET Operation Isimiso
Isimiso ukusebenza kwe-isihlukanisi uncika ukushaja tribo-electrostatic. Esikhathini tribo-electrostatic ibhande isihlukanisi (Izinombolo 2 futhi 3), impahla kufakwa igebe ewumngcingo 0.9 - 1.5 cm phakathi ezimbili okuhambisana Planar electrode. Izinhlayiya triboelectrically icala by interparticle contact. I amaminerali kahle icala(s) kanye nokumbiwa omubi icala(s) bakhangwa electrode okuphambene. Ngaphakathi izinhlayiya isihlukanisi kuthiwa sikhukhuleke ngumuntu okuqhubekayo ezihambayo evulekile-anezikhala ibhande abavezwa oluyi. Ibhande wenziwe impahla plastic futhi ushukumisela izinhlayiya ezakhelene electrode ngamunye ngase imikhawulo okuphambene isihlukanisi. Counter ukugeleza wamanje we izinhlayiya uhlukanisa futhi okuqhubekayo triboelectric ukushaja by kuyizinhlayiyana-kuyizinhlayiyana ukushayisana sihlinzekela ngokwahlukana multistage nemiphumela nangokuhlanzeka kakhulu futhi alulame yisikhungo esisodwa-pass. I triboelectric ibhande isihlukanisi ubuchwepheshe isetshenzisiwe ukwehlukanisa anhlobonhlobo izinto kuhlanganise Izingxube lwengilazi aluminosilicates / carbon (fly umlotha), calcite / asebenza ngebhethri, talc / Magnesite, futhi barite / asebenza ngebhethri.
Kukonke, umklamo isihlukanisi lilula ne ibhande ezihambisana ezinamasondo njengoba izingxenye ezinyakazayo kuphela. I electrode kukhona umile futhi yakhiwa i material onensika ngokufanele. Ubude isihlukanisi electrode cishe 6 amamitha (20 ft.) futhi ububanzi 1.25 amamitha (4 ft.) ngoba usayizi ogcwele amayunithi commercial. I ngesivinini ibhande kwenza throughputs eliphezulu kakhulu, kuya ku 40 amathani ngehora for usayizi ogcwele amayunithi commercial. Ukusetshenziswa amandla esingaphansi 2 kilowatt-amahora sethani licubunguliwe iningi amandla sokudliwa izinjini ezimbili ukushayela ibhande ngayinye.
Wokuhlelwa kwendikimba triboelectric ibhande isihlukanisi
Umniningwane ngokuhlukana zone
Njengoba singabona kuThebula 2, umehluko oyinhloko phakathi isihlukanisi benchtop nomshayeli ukuziphilisa nezentengiselwano isikali separators wukuthi ubude isihlukanisi benchtop cishe 0.4 izikhathi nobude umshayeli isikali nezentengiselwano isikali amayunithi. Njengoba kahle isihlukanisi kuyinto umsebenzi ubude electrode, ukuhlolwa ebhentshini ukuziphilisa ayikwazi asetshenziswa esikhundleni ukuhlolwa umshayeli isikali. ukuhlolwa Pilot ukuziphilisa kuyadingeka ukuze kutholakale umsuka wendaba yesihluku ukwehlukana ukuthi inqubo STET ingafinyelela, futhi ukunquma uma inqubo STET kungaba kuhlangabezanwe nalemigomo umkhiqizo ngaphansi inikezwe feed amazinga. Kunalokho, the isihlukanisi benchtop isetshenziswa siqambe ikhandidethi izinto cishe khombisa iyiphi ngokwahlukana abalulekile ezingeni umshayeli isikali. Imiphumela etholwe ebhentshini ukuziphilisa uzobe non-elungiselelwe, okulandelwa ukwehlukana waphawula lingaphansi kuka angathathwa baphawula phezu a commercial obujwayelekile isihlukanisi STET.
Ukuhlola e-isitshalo umshayeli kuyadingeka ngaphambi commercial isikali ukuthunyelwa, Nokho, sokuhlola ebhentshini ukuziphilisa kuyakhuthazwa njengoba isigaba sokuqala sohlelo ukuqaliswa ukuze noma iyiphi impahla inikezwe. Ngaphezu kwalokho, ezimweni lapho ukutholakala impahla kukhawulwe, the isihlukanisi benchtop ihlinzeka yithuluzi eliwusizo for the Ukuhlolwa ezinamathuba amaphrojekthi yimpumelelo (okuyi, amaphrojekthi lapho amakhasimende kanye umkhakha izinga okuhloswe inganqotshwa usebenzisa ubuchwepheshe STET).
ukuhlolwa Bench ukuziphilisa
Standard inqubo nokulingwa zazenziwa emhlabeni mgomo ukwandisa Fe okuhlushwa ukunciphisa lokuhlushwa gangue amaminerali. eziguquguqukayo engefani uhlole ukukhulisa yensimbi ukunyakaza ukucacisa yekuhambisa sandla amaminerali ezahlukene. Ohlangothini ukunyakaza waphawula phakathi benchtop ukuhlola kukhombisa ohlangothini ukunyakaza ngesikhathi isitshalo umshayeli yezomnotho.
Eziguquguqukayo uphenyo kuhlanganisiwe umswakama nesihlobo (RH), lokushisa, electrode polarity, isivinini ibhande voltage osetshenziswayo. kulezi, RH futhi lokushisa wedwa kungaba nethonya elikhulu ku-umehluko tribo-ukushaja futhi ngenxa yalokho on ngokwahlukana Imiphumela. Yingakho, elikhulu RH futhi lokushisa izimo babezimisele phambi liphenya umphumela eziguquguqukayo asele. amazinga amabili polarity abangu uhlole: i) phezulu electrode polarity omuhle futhi ii) electrode phezulu polarity omubi. Ukuze isihlukanisi STET, ngaphansi kwelungiselelo polarity enikeziwe ngaphansi elikhulu RH futhi lokushisa izimo, isivinini ibhande kuyinto eyinhloko ukulawula isibambo iqhakambisa umkhiqizo ebangeni yokutakula mass. Ukuhlola phezu isihlukanisi ebhentshini kusiza kwanikezwa ukukhanya oku umphumela eziguquguqukayo ezithile ezisebenzayo ukushaja tribo-electrostatic elinikeziwe amaminerali isampula, futhi ngenxa yalokho wathola imiphumela kanye izitayela lingasetshenziswa, ukuze ngezinga elithile, ukuze unciphise inani eziguquguqukayo futhi ukuhlolwa ukuze kwenziwe ngesikhathi esikalini umshayeli isitshalo. Ithebula 3 uhlu uhla izimo ngokwahlukana kusetshenziswa njengengxenye isigaba 1 inqubo nokuhlola ukuze tailings kanye amasampula itabirite.
Ithebula 3 ubala uhla izimo ngokuhlukana
| 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) |
Ukuhlolwa yayiqhutshelwa phezu benchtop isihlukanisi ngaphansi kwezimo batch, namasampula ukufunza 1.5 lbs. ukuhlolwa. A run ezishaywayo usebenzisa 1 lb. yezinto ezibonakalayo. yethulwa phakathi ukuhlolwa ukuqinisekisa ukuthi noma yimuphi umphumela kungenzeka carryover kusukela isimo odlule awuzange kubhekwa. Ngaphambi ukuhlolwa uqalwe ezibonakalayo homogenized futhi isampula izikhwama equkethe kokubili run futhi impahla ezishaywayo Ayekulungele. Ekuqaleni lokuhlolwa ngamunye lokushisa kanye nomswakama isihlobo (RH) sasibalwa usebenzisa Vaisala HM41 ngesandla Umswakama kanye lokushisa probe. Ububanzi lokushisa kanye RH kuwo wonke ucwaningo kwaba 70-90 ° F (21.1-32.2 (° C) futhi 1-39.6%, ngokulandelana. Ukuze ukuhlola RH aphansi futhi / noma izinga lokushisa eliphakeme, amasampula feed bese ezishaywayo zazigcinwa kuhovini omiswe ngesikhathi 100 ° C izikhathi phakathi 30-60 amaminithi. Ngokungqubuzanayo, ephakeme amagugu RH abangu attained ngokungeza nengcosana amanzi kuya impahla, kulandele homogenization. Ngemva RH futhi lokushisa sasibalwa ekuphakeleni ngayinye, isinyathelo esilandelayo kwaba ukusetha electrode polarity, isivinini ibhande voltage ezingeni oyifunayo. Gap amagugu wawugcinwa njalo 0.4 amayintshi (10.2 mm) phakathi nemikhankaso yokuhlola le tailings kanye amasampula itabirite.
Ngaphambi test ngasinye, encane okuphakelayo sub-isampula equkethe cishe 20g kwaba eqoqwe (eyabizwa ngokuthi 'Okuphakelayo'). Lapho ukubeka zonke eziguquguqukayo ukusebenza, okokusebenza yondliwa phakathi isihlukanisi benchtop Usebenzisa kagesi vibratory Element ngokusebenzisa maphakathi isihlukanisi benchtop. Amasampula zathathwa ekupheleni lokuhlolwa ngamunye futhi izisindo umkhiqizo ekupheleni 1 (eyabizwa ngokuthi 'E1') futhi umkhiqizo ekupheleni 2 (eyabizwa ngokuthi 'E2') babezimisele usebenzisa zomthetho i-trade nokubala isikali. Ukulandela test ngasinye, sub-amasampula elincane eliqukethe cishe 20 g E1 futhi E2 nazo eqoqwe. ezithela iMisa E1 futhi E2 bachazwa ngu:
laphofuthiE1 futhi futhiE2 kukhona ezithela mass E1 futhi E2, ngokulandelana; futhi izisindo isampula eqoqwe emikhiqizweni isihlukanisi E1 futhi E2, ngokulandelana. Maqondana nezibonelo kokubili, Fe okuhlushwa senyuselwa umkhiqizo E2.
Ukuze iqoqo sub-amasampula ngamunye (okuyi, Okuphakelayo, E1 futhi E2) Loi futhi oxides main Ukwakheka ngu XRF wayezimisele. Fe2 I3 okuqukethwe babezimisele ukusuka amagugu. Ukuze tailings isampula Loi ngeke ngqo ezihlobene okuqukethwe goethite e isampuli njengoba amaqembu obusebenzayo hydroxyl e goethite ngeke oxidize ku H2 Ig [10]. Ngokuphambene, ngokuba itabirite isampula Loi ngeke ahlobane nqo aqukethe ka carbonates e isampuli, njengoba calcium ne-magnesium carbonates ngeke ukubola ku oxides yabo eyinhloko okuholela ekukhishweni CO2g kanye sub isampula ezilandelanayo ukulahlekelwa isisindo. XRF ubuhlalu Ayekulungele ngokuxuba 0.6 amagremu yezimbiwa Isampula 5.4 amagremu lithium tetraborate, okuyinto sikhethwe ngenxa ukwakheka kwamakhemikhali kokubili tailings kanye amasampula itabirite. XRF ukuhlaziywa abangu benganhlanhlathi Loi.
Ekugcineni, Fe yokutakula EFe kumkhiqizo (E2) futhi Sio2 ukwenqatshwa Qfuthi kuye kwabalwa. EFe is iphesenti Fe kwatholakala CONCENTRATE kulelo original okuphakelayo isampula kanye Qsio2 ngamaphesenti asuswe yasekuqaleni okuphakelayo isampula. EFe futhi Qfuthi bachazwa ngu:
lapho Ci,(okuphakelayo,E1, E2) iyona okuhlushwa amaphesenti kwesejwayelekile for sub-isampula sika i ingxenye (isib., Fe, Sio2)
amasampula Mineralogy
Iphethini XRD ezibonisa izigaba eziyinhloko amaminerali ngokuba tailings kanye amasampula itabirite zibonisiwe Kumdwebo 4. Ukuze tailings sampula main Fe izigaba ukuyithola kukhona goethite, hematite futhi magnetite, futhi main gangue amaminerali kuyinto asebenza ngebhethri (Fig 4). Ukuze isampuli itabirite main Fe izigaba ukuyithola kukhona hematite futhi magnetite futhi main gangue amaminerali kukhona asebenza ngebhethri futhi dolomite. Magnetite livela trace lokuhlala e amasampula kokubili. hematite Pure, goethite, futhi magnetite aqukethe 69.94%, 62.85%, 72.36% Fe, ngokulandelana.
amaphethini D. A - Tailings isampula, B - isampula Itabirite
ucwaningo Bench ukuziphilisa
Uchungechunge test iphelela zazenziwa ku ngayinye amaminerali okuhloswe ngaso okwenza Fe kanye nokuncipha Sio2 okuqukethwe. Lesitshalo sokugxila ukuze E1 kuyoba kukhombisa negative ukushaja ukuziphatha ngenkathi zinhlobo okuhlushwa ukuze E2 ku-positive ukushaja ukuziphatha. Ephakeme ibhande ngesivinini ingahluphi ukuba ngokucubungula tailings isampula; Nokho, umphumela walesi variable wedwa kwatholakala ukuthi zincane ngoba isampuli itabirite.
Imiphumela esijwayelekile ukuze tailings kanye amasampula itabirite ethulwa Fig 5, eyayibonakala ibalwa kusukela 6 futhi 4 ucwaningo, ngokulandelana. Fig 5 inikeza isilinganiso mass isivuno kanye ne-chemistry indawo yokutshala ukudla kwazo kanye nemikhiqizo E1 futhi E2. Ngaphezu kwalokho, uzungu ngalinye kuveza ngcono noma ukwehla lokuhlushwa (E2- Okuphakelayo) ngoba ingxenye isampula ngalinye isb, Fe, Sio2 kweqanda ezihlobene nokwanda emakamu ukuba E2, ngenkathi amanani negative ahlobene ukwehla emakamu ukuba E2.
Fig.5. Isilinganiso mass ezithela kanye ne-chemistry ngoba Okuphakelayo, E1 futhi E2 imikhiqizo. Amabha amaphutha amelela 95% ukuzethemba ngezikhawu.
Ukuze tailings isampula Fe okuqukethwe lenyuka lisuka kwabangaba 29.89% ukuze 53.75%, ngokwesilinganiso, at isivuno mass futhiE2 - noma okusindayo yokutakula global – ka 23.30%. Lokhu kuhambelana Fe yokutakula ( futhi Silica ukwenqatshwa (QE2 ) namagugu 44.17% futhi 95.44%, ngokulandelana. Okuqukethwe Loi Kwandiswa kusukela 3.66% ukuze 5.62% okukhombisa ukuthi ukwanda Fe okuqukethwe kuhlobene nokwanda okuqukethwe goethite (Fig 5).
Ukuze isampuli itabirite Fe okuqukethwe lenyuka lisuka kwabangaba 47.68% ukuze 57.62%, ngokwesilinganiso, at isivuno mass futhiE2 -ka 65.0%. Lokhu kuhambelana Fe yokutakula EFe( futhi Silica ukwenqatshwa (Qsio2) namagugu 82.95% futhi 86.53%, ngokulandelana. I Loi, MgO futhi Cao okuqukethwe zandile kusukela 4.06% ukuze 5.72%, 1.46 ukuze 1.87% futhi kusukela 2.21 ukuze 3.16%, ngokulandelana, okukhombisa ukuthi dolomite ihamba siye ohlangothini olufanayo njengoba Fe esindayo amaminerali (Fig 5).
Maqondana nezibonelo kokubili,AL2 I3 , MNO futhi P Ubonakala ukushaja luhamba luye ohlangothini olulodwa njengoba Fe esindayo amaminerali (Fig 5). Kuyilapho oyifunayo ukuze wehlise lokuhlushwa lezi zinhlobo ezintathu, emakamu ahlangene we Sio2, AL2 , I3 , futhiE2 MNO futhi P lehla ngoba amasampula kokubili, ngakho-ke umphumela Imininingwane izuzwe usebenzisa isihlukanisi benchtop kuyinto isithuthukisi e umkhiqizo Fe ebangeni ukwehla ngo ezingcolisa lokuhlushwa.
Kukonke, benchtop ukuhlolwa kwabonisa ubufakazi ukushaja ngempumelelo nokuhlukaniswa zensimbi Silica izinhlayiya. I ezithembisa nemiphumela laboratory isikali basikisela ukuthi ukuhlolwa umshayeli isikali kuhlanganise maqembu lokuqala nelesibili kufanele kwenziwe.
Ingxoxo
Idatha zokuhlola kusikisela ukuthi isihlukanisi STET kuholele ekwenyukeni ebalulekile Fe nokuqukethwe ngenkathi kanyekanye ekunciphiseni Sio2 okuqukethwe.
Esebubonisile wokuthi ukuzihlukanisa triboelectrostatic kungaholela nokwanda okuphawulekayo Fe okuqukethwe, ingxoxo ukubaluleka imiphumela, ku esiphezulu okumele izuzwe Fe okuqukethwe ku izidingo ukufunza ubuchwepheshe kuyadingeka.
Ukuqala, kubalulekile ukuze baxoxe sobala ukushaja ukuziphatha zinhlobo amaminerali e amasampula kokubili. Ukuze tailings sampula yezingxenye esemqoka babe Fe oxides futhi asebenza ngebhethri futhi imiphumela yokulinga wabonisa ukuthi Fe oxides bagxila ukuze E2 ngenkathi asebenza ngebhethri bagxila ukuze E1. Ngezindlela lolumalula, kungashiwo ukuthi Fe oxide izinhlayiya aluthola icala omuhle nokuthi izinhlayiya asebenza ngebhethri aluthola icala omubi. Lokhu kuziphatha uhambisane ubunjalo triboelectrostatic kokubili amaminerali njengoba kuboniswa Ferguson (2010) [12]. Ithebula 4 ikhombisa sobala uchungechunge triboelectric tetimbiwa ezisuselwe ngokwahlukana exhasa, futhi kukhombisa ukuthi asebenza ngebhethri itholakala ezansi uchungechunge ukushaja ngenkathi goethite, magnetite futhi hematite zitholakala phezulu ochungechungeni. Minerals phezulu uchungechunge azothanda ukushaja omuhle, ngenkathi amaminerali ezansi azothanda ibe necala omubi.
Ngokwesinye isandla, I-isampuli itabirite yezingxenye esemqoka babe hematite, asebenza ngebhethri futhi dolomite nemiphumela zokuhlola wabonisa ukuthi Fe oxides kanye dolomite bagxila ukuze E2 ngenkathi asebenza ngebhethri bagxila ukuze E1. Lokhu kubonisa ukuthi hematite izinhlayiya kanye dolomite aluthola icala emihle kanti asebenza ngebhethri izinhlayiya aluthola icala omubi. Njengoba singabona kuThebula 4, carbonates zitholakala phezulu uchungechunge tribo-electrostatic, okukhombisa ukuthi izinhlayiya carbonate bavame ukuthola icala omuhle, futhi ngenxa yalokho ukuba bagxila ukuze E2. Bobabili dolomite futhi hematite abangu bagxila luhamba luye ohlangothini olulodwa, okubonisa ukuthi ekugcineni kube nomphumela ngoba hematite izinhlayiya ebukhoneni asebenza ngebhethri futhi dolomite kwaba ukuthola icala omuhle.
Ohlangothini ukunyakaza kwezinhlobo mineralogical kwisempula ngamunye libaluleke ngezikulu, njengoba eyonquma esiphezulu okumele izuzwe Fe ebangeni ingatholakala esebenzisa pass olulodwa usebenzisa tribo-electrostatic ibhande isihlukanisi ubuchwepheshe.
Ukuze tailings kanye amasampula itabirite esiphezulu okumele izuzwe Fe okuqukethwe izonqunywa izici ezintathu: i) Inani Fe e Fe esindayo amaminerali; ii) lo asebenza ngebhethri ubuncane (Sio2 ) okuqukethwe bungatholakala futhi; iii) Inombolo contaminants ezihambayo ohlangothini olufanayo njengoba Fe esindayo amaminerali. Ukuze tailings sampula le ezingcolisa main ezihambelayo isiqondiso efanayo Fe eziveza amaminerali kukhona Al2 I3 MNO namaminerali nithela, isikhathi isampuli itabirite le ezingcolisa ezisemqoka Cao MgO Al2 I3 namaminerali nithela.
| 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 | ---- |
| Quartz | ------- |
Ithebula 4. Sobala uchungechunge triboelectric tetimbiwa ezisuselwe ngokwahlukana exhasa. Kushintshwe kusukela D.N Ferguson (2010) [12].
Ukuze tailings isampula, okuqukethwe Fe sasibalwa ngesikhathi 29.89%. XRD izibalo zikhomba ukuthi esigabeni eyinhloko kuyinto goethite, kulandele hematite, ngakhoke esiphezulu okumele izuzwe Fe okuqukethwe uma ngokwahlukana ehlanzekile kwakunokwenzeka kungaba phakathi 62.85% futhi 69.94% (okuyizinto okuqukethwe Fe ka goethite okumsulwa kanye hematite, ngokulandelana). Manje, ngokwahlukana ahlanzekile akunakwenzeka njengoba Al2, I3 MNO namaminerali P eziveza lihamba luhamba luye ohlangothini olulodwa njengoba namaminerali nithela Fe-, futhi ngaleyo ndlela noma imuphi ukwanda Fe okuqukethwe nakho kuzoholela ekwenyukeni yalezi ezingcolisa. Khona-ke, ukwandisa okuqukethwe Fe, inani asebenza ngebhethri ukuze E2 kuyodingeka kakhulu kwehle kuze kube seqophelweni ke ezenzé zaba yize ukunyakaza , MNO futhi P kumkhiqizo (E2). Njengoba kuboniswe kuThebula 4, asebenza ngebhethri has ukuthambekela eqinile ukuze nje athole icala omubi, ngakho-ke ngokungabi bikho namanye amaminerali kokuba esigamakweni okusolakala ukuthi omubi ukushaja ukuziphatha ke sizokwazi kakhulu wehlise nokuqukethwe kwalo kumkhiqizo (E2) esebenzisa pass sokuqala usebenzisa triboelectrostatic ibhande isihlukanisi ubuchwepheshe.
Ngokwesibonelo, uma sicabanga ukuthi konke okuqukethwe Fe ku tailings isampula lihlotshaniswa ukuba goethite (Feo(OH)), nokuthi gangue oxides kuphela Sio2, Al2I3 futhi MNO, ke okuqukethwe Fe kumkhiqizo bazonikezwa ngu:
Fe(%)=(100-Sio2 – (Al2 I3 + MNO*0.6285
lapho, 0.6285 ngamaphesenti Fe e goethite okumsulwa. Eq.4 okubonisa indlela ukuncintisana olwenzeka ukuba agxilise Fe njengoba AL2I3 + MNO kwandisa ngenkathi Sio2 incipha.
Ukuze isampuli itabirite okuqukethwe Fe sasibalwa ngesikhathi 47.68%. XRD izibalo zikhomba ukuthi esigabeni eyinhloko kuyinto hematite ngakhoke esiphezulu okumele izuzwe okuqukethwe Fe uma ngokwahlukana ehlanzekile kwakunokwenzeka kungaba eduze 69.94% (okuyinto okuqukethwe Fe ka hematite okumsulwa). okuxoxwe Njengoba Ngenxa tailings sampula ngokwahlukana ehlanzekile ngeke kwenzeke njengoba Cao, MgO, Al2 I3 namaminerali nithela lihamba luhamba luye ohlangothini olulodwa njengoba hematite, ngakho-ke ukwandisa Fe okuqukethwe Sio2 okuqukethwe kufanele encishisiwe. Uzitshela ukuthi konke okuqukethwe Fe kule isampula lihlotshaniswa ukuba Hematite (Fe2I3) nokuthi oxides kuphela eziqukethwe gangue amaminerali kukhona Sio2, Cao, MgO, Al2I3 futhi MNO; ke Fe okuqukethwe kule mkhiqizo eyanikezwa:
Fe(%)=(100-Sio2-Cao + MgO +Al2I3+MNO+UMTHETHO*0.6994
lapho, 0.6994 ngamaphesenti Fe e hematite okumsulwa. Kufanele waphawula ukuthi Eq.5 kuhlanganisa Loi, ngenkathi Eq.4 kungaqali. Ukuze isampuli itabirite, i-Loi lihlotshaniswa yokubakhona carbonates kanti tailings isampula ihlobenenamanye ukuba namaminerali nithela Fe-.
Ngokusobala, kokubili tailings kanye amasampula itabirite kungenzeka ukwandisa okuqukethwe Fe ngokunciphisa okuqukethwe Sio2; Nokho, njengoba kukhonjisiwe kulesibonelo Eq.4 futhi Eq.5, esiphezulu okumele izuzwe Fe okuqukethwe kuzokhawulelwa ngokuqondisa ukunyakaza futhi lokuhlushwa oxides ezihambisana gangue amaminerali.
Ngokomthetho, lokuhlushwa Fe e amasampula kokubili angase eminye kukhuphuke ngo esebenzisa pass wesibili isihlukanisi STET lapho Cao,MgO Al2 I3 futhi MNOnamaminerali nithela angase ehlukanisiwe namaminerali nithela Fe-. ngokuhlukana enjalo kwakuyoba nokwenzeka uma iningi asebenza ngebhethri e isampuli isuswe ngesikhathi kudlula lokuqala. In the ukungabikho asebenza ngebhethri, ezinye ezisele gangue kufanele namaminerali ngemcondvo icala kolunye uhlangothi of goethite, hematite futhi magnetite, okwakuyoholela anda Fe okuqukethwe ngabe. Ngokwesibonelo, I-isampuli itabirite futhi ezinze indawo dolomite futhi hematite ochungechungeni triboelectrostatic (Bona Ithebula 4), dolomite / hematite ngokwahlukana kufanele kwenzeke njengoba dolomite enokuthambekela eqinile ukukhokhisa i omuhle maqondana hematite.
Njengoba ezidingidwa esiphezulu okumele izuzwe Fe okuqukethwe ingxoxo izidingo okuphakelayo ubuchwepheshe kuyadingeka. I STET tribo-electrostatic ibhande isihlukanisi kudinga impahla okuphakelayo ukuba ibe ngumhlabathi owomile fake. Kakhulu nengcosana umswakama kungaba nethonya elikhulu ku-umehluko tribo-ukushaja ngakhoke umswakama okuphakelayo kufanele kwehle kuze <0.5 wt.%. Ngaphezu kwalokho, 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, Ngokwesinye isandla, 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.
Imiphumela ebhentshini ukuziphilisa owethulwe lapha ubonisa ubufakazi obunamandla ukushaja nokuhlukaniswa Fe esindayo amaminerali avela asebenza ngebhethri usebenzisa triboelectrostatic ibhande ngokuhlukana.
Ukuze tailings isampula Fe okuqukethwe lenyuka lisuka kwabangaba 29.89% ukuze 53.75%, ngokwesilinganiso, at isivuno mass 23.30%, okuhambelana Fe yokutakula futhi Silica kwenqatshwa namagugu 44.17% futhi 95.44%, ngokulandelana. Ukuze isampuli itabirite Fe okuqukethwe lenyuka lisuka kwabangaba 47.68 % ukuze 57.62%, ngokwesilinganiso, at isivuno mass 65.0%, okuhambelana Fe yokutakula futhi Silica kwenqatshwa namagugu 82.95% futhi 86.53%, ngokulandelana. Le miphumela yaqedwa ngo-a isihlukanisi ukuthi luncane futhi kancane kahle ngaphandle isihlukanisi commercial STET.
okutholakele kokulinganisa ibonisa ukuthi kokubili tailings kanye amasampula itabirite esiphezulu okumele izuzwe Fe okuqukethwe kuzoncika ubuncane okumele izuzwe asebenza ngebhethri okuqukethwe. Ngaphezu kwalokho, ekufezeni ephakeme Fe amamaki kungenzeka esebenzisa pass wesibili isihlukanisi STET ibhande.
Imiphumela yalolu cwaningo wabonisa ukuthi ongaphakeme-ebangeni nsimbi izinhlawulo kungenziwa ngcono esebenzisa STET tribo-electrostatic ibhande isihlukanisi. umsebenzi Okwengeziwe esikalini umshayeli isitshalo Kunconywa ukucacisa ibanga yensimbi CONCENTRATE nokululama ongase ufinyelelwe. Ngenxa yokuhlangenwe nakho, nokuvulwa umkhiqizo kanye / noma ibanga ngeke kakhulu ngcono at umshayeli isikali ukucutshungulwa, njengoba kuqhathaniswa ebhentshini-ngezindodla idivayisi test ukusetshenziselwa phakathi kwalezi zilingo nsimbi. I STET tribo-electrostatic ngokwahlukana inqubo ingase inikeze Izinzuzo ebaluleke phezu ezivamile zokuwugaya ngoba nsimbi izinhlawulo.
