Thesis (MTech. degree in Chemistry)--Tshwane University of Technology, 2010.

published_or_final_version / abstract / toc / Chemistry / Master / Master of Philosophy

High-pressure homogenization using a new flat valve homogenizer in combination with enzymatic digestion with a crude protease was investigated as a means of releasing Se compounds from zoological and botanical matrices prior to slurry introduction GF-AAS. Timed trials with four zoological certified reference materials (CRMs), three botanical reference materials (RMs), and a food crop indicated that Se release was quantitative after homogenization or became quantitative within 1 h of digestion at 60°C. / The same technique was employed on five animal feed samples. / A new model of homogenizer equipped with ceramic homogenizing valve was evaluated in terms of analyte metal contamination levels within the final sample dispersion. / Five animal feed samples and four wood pulp samples, were investigated for their content of Cu, Fe and Mn using high-pressure homogenization as the sample preparation technique prior to GF-AAS. Dispersions of dried animal feeds were sub-sampled reliably after 7 days of storage at 4°C. Trials on pulp samples indicated that pulps could be sub-sampled reliably after 1 day of storage. (Abstract shortened by UMI.)

Phosphorus (P) is one of the essential nutrients for living organisms; however, excess P in aquatic systems often causes environmental and ecological problems including eutrophication. Removal of P from domestic wastewater, industrial wastewater, and agricultural organic-waste systems is required to minimize loading of P to receiving water bodies. A variety of sorbents or filter materials have previously been evaluated for P removal, including natural materials, industrial byproducts, and synthetic products. Among these materials industrial byproducts were reported as most effective. However, only a few of these studies were based on field experiments. Pharmaceutically active compounds (PhACs) and acesulfame-K (an artificial sweetener) are emerging contaminants observed in wastewater. The removal of PhACs in conventional wastewater treatment systems has been studied; however, few studies on alternative treatment systems are available. Studies related to the removal of acesulfame-K are even more limited. This thesis was focused on evaluation of basic oxygen furnace slag (BOFS), a byproduct from the steel manufacturing industry, as a potential reactive media for P removal from surface water and wastewater. The removal of PhACs and acesulfame-K in wastewater treatment systems containing BOFS as a treatment component was also evaluated. The effectiveness of BOFS for removing P from lake water was evaluated in a three year pilot-scale hypolimnetic withdrawal P treatment system at Lake Wilcox, Richmond Hill, Ontario. Phosphate concentrations of the hypolimnion water ranged from 0.3 to 0.5 mg L-1. About 83-100% P was removed during the experiment. The reactive mixtures were changed each year to improve the performance of the treatment system. Elevated pH (9-12) at the effluent of the treatment system was adjusted by sparging CO2(g) to near neutral pH. Elevated Al was removed through this pH adjustment. Elevated concentrations of V were removed in a column containing 5 wt% zero valent iron (ZVI) mixed with sand (0.5 m3) at the end of the BOFS based column. Removal of P in the BOFS based media is attributed to adsorption and co-precipitation at the outer layer of BOFS. Geochemical modeling results showed supersaturation with respect to hydroxyapatite, ß-tricalciumphosphate, aragonite, and calcite. Solid phase analyzes of the BOFS based reactive media collected after completion of the year 2 experiment (spent media) through combination of scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), and X-ray absorption near edge structure spectroscopy (XANES) support the presence of calcium phosphate minerals on the outer layer of the spent media. A multistep wastewater treatment experiment was carried out in an indoor facility at the Center for Alternative Wastewater Treatment, Fleming College, Lindsay, Ontario, Canada. This experiment evaluated the removal of P, ammonia, cBOD5, COD, E. coli, total coliform, and trace metals in a series of treatment cells including a mixing cell, a vertical subsurface flow aerobic cell, a vertical subsurface flow P treatment cell containing BOFS, and a horizontal subsurface flow anaerobic cell. About 97-99% removal of P, NH3, cBOD5, E. coli, and total coliform; and ~72% removal of COD were achieved in the treatment system. The mixing cell and the aerated cell reduced the concentrations of P, ammonia, cBOD5, E. coli, and total coliform significantly and the P treatment cell provided additional treatment. However, the primary objective of the P treatment cell was to reduce P concentrations to the acceptable range according to the water quality guidelines. The P treatment cell had successfully fulfilled this objective. Elevated concentration of Al and V were also observed in the P treatment cell effluent. The concentration of Al decreased to below the guideline value of 0.075 mg L-1 after introducing a pH adjustment unit between the P treatment cell and the anaerobic cell. The concentration of V was decreased in the anaerobic cell effluent. However, the effluent concentration of V was much higher than the guideline value. Geochemical speciation modeling results showed supersaturation with respect to hydroxyapatite, ß-tricalciumphosphate, aragonite and calcite along the flow path. Accumulation of P on the outer layer of the spent BOFS media was identified by energy dispersive X-ray spectroscopy (EDX). Although X-ray photoelectron spectroscopy (XPS) can provide information to a depth of 5-7 nm from the outer layer of the spent media, both Ca and P were positively identified in some of the samples. Accumulation of P at the edge of the grains of the spent media was clearly identified on the element map of polished cross-sections and corresponding FTIR spectra. The phosphate and carbonate functional groups were identified by the distribution of different vibrational frequencies through FTIR spectroscopy. The presence of calcite and hydroxyapatite were inferred based on the wave numbers assigned for these minerals in the literature. Finally, X-ray absorption near edge structure spectroscopy (XANES) on the outer layer samples from the spent BOFS media and corresponding linear combination fitting analysis indicated the presence of ß-tricalciumphosphate, hydroxyapatite, and calcium phosphate dibasic. Based on the observations from the indoor wastewater treatment experiment, a multistep demonstration-scale outdoor wastewater treatment experiment was conducted to investigate the applicability of the integration of the P treatment technology and engineered wetland technology at a relatively large scale prior to a full-scale field installation. The anaerobic treatment cell was not included in this outdoor system because this unit did not efficiently remove ammonia and metals (e.g. V) from the Cell 4 effluent in the indoor system. A 10 cm layer of zero valent iron was placed at the bottom part of the down flowing P treatment cell to address the elevated V in the P treatment cell effluent observed in the indoor system and also to treat PhACs in the effluent. More than 99% removal of P, E. coli, and total coliform; >82, >98, and >76% removal of ammonia, cBOD5, and COD were achieved in this treatment system. The effluent pH (10.88±1.47) was neutralized and the concentration of V remained < 0.006 mg L-1. The Al concentration was adjusted to <0.075 mg L-1 with the neutralization of pH. Geochemical speciation modeling results showed the supersaturation of hydroxyapatite, ß-tricalciumphosphate, octatricalciumphosphate, aragonite, and calcite. The FTIR and XANES spectra showed the presence of calcium phosphate minerals on the outer layer of the spent media. Removal of the PhACs, including caffeine, ibuprofen, carbamazepine, naproxen, and sulfamethoxazole, and acesulfame-K was monitored in the demonstration-scale outdoor wastewater treatment system, which consisted of five different treatment cells including a horizontal subsurface flow constructed wetland, a vertical subsurface flow aerated cell, a vertical subsurface flow BOFS cell, and a pH neutralization unit. Significant removal of caffeine (>75%) and ibuprofen (50-75%), and moderate removal of sulfamethoxazole and naproxen (25-50%) were observed. The removal of carbamazepine was less effective with <25% removal observed. Acesulfame-K was also persistent along the flow path with <25% removal. This study demonstrated that removal of P from lake water and wastewater in excess of 95% could be achieved using BOFS as a reactive media. Integration of this media into an engineered wetland system enhances its performance in removing nutrients and other wastewater contaminants.

Darbe nagrinėta biokuro kūryklų įvairovė, išmetamų teršalų poveikis aplinkai bei žmogui. Pagrindinis darbo tikslas - ištirti biokuro kūryklų (katilo ir krosnies) išmetamų dūmų sudėtį ir teršalų koncentracijas bei įvertinti jų atitikimą normatyviniams dokumentams. Magistriniame darbe apžvelgta biokuro sąvoka, sudėtis ir savybės. Apžvelgta oro ir deguonies kiekio įtaka degimo procesui. Taip pat darbe apžvelgti katilų ir krosnių pagrindiniai elementai bei jų veikimo principai. Nagrinėjama oro taršos problema bei emisijos, deginant biokurą. Darbe pateikiama biokuro degimo tyrimo metodika, veiksniai nuo kurių priklauso biokuro sudegimo pilnumas. Tyrimai atlikti naudojantis dviejų skirtingų namų 2011 m. šildymo sezono duomenimis. Pamatuoti katilo bei krosnies emisijų kiekiai ir palyginta, kuris įrenginys mažiausiai teršia aplinką, remiantis normatyviniais dokumentais. Taip pat matuoti deguonies kiekio dūmuose svyravimai visame degimo procese. Remiantis informacijos šaltiniuose pateiktomis formulėmis apskaičiuotas optimalus oro pertekliaus koeficientas skirtingiems degimo įrenginiams. / This paper analyzes a variety of biofuel furnaces, emissions and the impact on humans. The main aim - to investigate bio flue (boiler and furnace), the composition of the smoke emissions and concentrations of pollutants and to assess their compliance with the normative documents. This thesis covers an overview of the concept of bio-fuels, composition and properties. The theoretical aspects of air and oxygen influence the combustion process. Also look at the boilers and heating elements and their operating principles. The present problem of air pollution and emissions from combustion of biofuels. The paper presents the combustion of biofuels research methodology, the factors which determine the completeness of combustion of biofuels. Investigations were carried out using two different houses in 2011. heating season. Measure the boiler or furnace emissions and compared to plant environmentally friendly, according to legal documents. Also measure the oxygen content of flue variations throughout the combustion process. Based on information provided by sources in the equations estimated optimum excess air ratio for different combustion device.

Industry is heavily dependent on the process of combustion and with a projected rapid increase for the demand of combustion-derived energy it is imperative to expose a new age of engineering professionals to the discipline of combustion engineering. One purpose of this study was to modify an existing scaled-down industrial furnace and to retrofit it with the ability to interchange burners for academic application and combustion testing. A number of available industrial burners are presented and their qualities and drawbacks discussed. The modification of an existing scaled-down industrial tunnel furnace is proposed in this work with the objective of providing users with exposure to the control and safe operating strategies associated with industrial combustion. The furnace system simulates a square-shaped tunnel geometry commonly found in industrial applications. A single nozzle mix burner is mounted along the furnace axis and operated with supporting equipment such as a burner control safeguard, a gas train, and an air supply. Details of the furnace are provided in this work. The concept of radiative heat transfer within a combustion enclosure is demonstrated through furnace simulation with Hottel’s Zone Method. / Thesis (Master, Chemical Engineering) -- Queen's University, 2010-07-19 09:50:22.797

No description available.

The scope of these studies was two-fold: to evaluate high pressure homogenized slurries as a rapid means of screening wood pulps for their Cu, Mn and Fe content and to evaluate the high pressure homogenization in combination with chelating agents or enzymatic digestion for the liberation/extraction of metal ions from this matrix. / Cu, Mn and Fe were determined successfully in pulp samples using high-pressure homogenization prior to slurry introduction-GF-AAS. The analysis time of the method from sample acquisition to determination was of the order of a few minutes per sample. / Different cellulose swelling/dissolution agents were evaluated for the generation of quasi-stable pulp suspensions, rich in cellulose. High-pressure homogenization alone or in combination with chelating agents or enzymatic digestion was also investigated as a means of quantitatively releasing these metal ions into the liquid phases. / A new model of homogenizer equipped with ceramic homogenizing valve with a few modifications was evaluated in terms of metal contamination levels within the final sample dispersion. (Abstract shortened by UMI.)

Στην παρούσα εργασία, εξετάστηκε η δυνατότητα χρήσης της σκωρίας κλιβάνου ηλεκτρικού τόξου (Electric Arc Furnace Slag- EAFS), ως πρώτη ύλη στη διεργασία παραγωγής τσιμέντου μπελιτικού τύπου. Η σκωρία κλιβάνου ηλεκτρικού τόξου (EAF) είναι ένα παραπροϊόν της μεταλλουργικής βιομηχανίας. Προκύπτει από την τήξη σε κλίβανο ηλεκτρικού τόξου (Electric Arc Furnace - EAF) παλαιοσιδήρου (ferrous scrap). Σύμφωνα με την American Society for Testing Materials (ASTM), η σκωρία ορίζεται ως ένα μη μεταλλικό προϊόν. Η σκωρία είναι ένα τήγμα που αποτελείται κυρίως από πυριτικές ενώσεις του ασβεστίου ενωμένες οξείδια σιδήρου, αλουμινίου, ασβεστίου και μαγνησίου και παράγεται ταυτόχρονα με τον χάλυβα μέσα σε κλίβανο. Η ποσότητα σκωρίας που παράγεται στα χαλυβουργεία, ως παραπροϊόν της παραγωγικής διαδικασίας, αποτελεί ποσοστό περίπου 13% - 18% επί της συνολικής ποσότητας τροφοδοσίας του κλιβάνου με αποτέλεσμα οι μεταλλουργικές σκωρίες να είναι ένα από τα μεγαλύτερα σε ποσότητα βιομηχανικά παραπροϊόντα. Ως συνέπεια, οι χαλυβουργίες αντιμετωπίζουν προβλήματα απόθεσης και διάθεσης των σκωριών καθώς και τις περιβαλλοντικές επιπτώσεις που προκύπτουν από αυτά. Μια κατηγορία τσιμέντων για την οποία υπάρχει έντονο ενδιαφέρον τα περίπου τελευταία 20 χρόνια είναι τα μπελιτικά τσιμέντα, καθώς παρουσιάζουν μειωμένη, θερμοκρασία έψησης και εκπομπή CO2. Η διαφορά των ανωτέρω τσιμέντων με τα τσιμέντα τύπου Portland είναι τα μειωμένα επίπεδα της φάσης του πυριτικού τριασβεστίου (C3S), απόρροια της χαμηλής θερμοκρασίας έψησης (~1350°C) γεγονός που τα κατατάσσει στην κατηγορία των φιλικών προς το περιβάλλον τσιμέντων. Επιπρόσθετα η αξιοποίηση παραπροϊόντων ως A! Ύλες, που παρουσιάζουν χημική σύσταση κατάλληλη για την παραγωγή τσιμέντου, οδηγεί σε μερική μείωση της ζήτησης Α! υλών και σε ελάττωση των εκπομπών CO2, καθώς αποτελούν πηγή CaO ελαττώνοντας την ανάγκη για απανθράκωση του CaCO3. Μελετήθηκε η δυνατότητα προσθήκης σκωρίας EAF ως Α! ύλης για την παραγωγή τσιμέντων μπελιτικού τύπου. Οι πρώτες ύλες που χρησιμοποιήθηκαν για την προετοιμασία των μιγμάτων ήταν ασβεστόλιθος, αργιλικός σχιστόλιθος καθώς και σκωρία κλιβάνου ηλεκτρικού τόξου (EAF). Η EAFS προήλθε από την χαλυβουργία «SOVEL» (θυγατρική της «ΣΙΔΕΝΟΡ») της οποίας η ετήσια παραγωγή σε χάλυβα είναι 750 kt ενώ σε EAFS 97.5 kt. Οι πρώτες ύλες αναλύθηκαν ως προς την χημική τους σύσταση με τη χρήση φθορισμομετρίας ακτίνων X (XRF, Philips PW 2400) και προσδιορίστηκε η ορυκτολογική τους σύσταση μέσω περιθλασιμετρία ακτίνων Χ (XRD, D5000 Siemens) ποιοτικά και ποσοτικά (QXRD, μέθοδος Reitveld). Για τη σκωρία πραγματοποιήθηκε παρατήρηση της μικροδομής της καθώς και στοιχειακή ανάλυση με ηλεκτρονική μικροσκοπία σάρωσης (SEM-EDS), βάση των οποίων κρίθηκε κατάλληλη να υποκαταστήσει μέρος των Α! υλών στην παραγωγή τσιμέντου . Τέσσερεις τύποι clinker παρήχθησαν με 0κ.β.% (BC), 5κ.β.% (BC5) 10κ.β.% (BC10) και 20κ.β.% (BC20) σκωρία EAF με στόχο την διατήρηση του μπελίτη σε υψηλή περιεκτικότητα (>55%). Η έψηση των clinker πραγματοποιήθηκε στους 1380ºC. Η θερμοκρασία έψησης προσδιορίστηκε από προκαταρκτικές δοκιμές έψησης στο θερμοκρασιακό εύρος 1280°C-1400°C, με βάση τα αποτελέσματα της ελευθέρας ασβέστου και την εξέλιξη της μικροδομής. Η μικροδομή των παραγόμενων clinker αποτελείται κυρίως από κρυστάλλους μπελίτη και αλίτη, ενώ η ρευστή φάση (C3A+C4AF) παρουσιάζεται ως μήτρα γύρω από τους κρυστάλλους με λεπτοκρυσταλλική δομή. Τα παραγόμενα τσιμέντα υστερούν σε πρώιμες αντοχές. Εντούτοις, τα αποτελέσματα των αντοχών για τις 28 ημέρες που για τα BC, BC5, BC10 και BC20 είναι 47.5 MPa, 46.6 MPa , 42.8 MPa και 35.5 MPa αντίστοιχα πληρούν τις προϋποθέσεις για ένταξή τους στην κατηγορία OPC CEMI 32.5N, σύμφωνα με το EN 197-1. Παρατηρήθηκε επίσης, ότι τα BC10 και BC20 συμπεριφέρονται ως ταχύπηκτα, ενώ η υγεία σε όλες τις περιπτώσεις δεν υπερβαίνει το 1mm. Τα αποτελέσματα δείχνουν ότι η σκωρία EAF μπορεί να χρησιμοποιηθεί για την παραγωγή των εν λόγω τσιμέντων αλλά και ότι τα τσιμέντα αυτού του τύπου υστερούν στην ανάπτυξη των πρώιμων αντοχών έναντι των Portland. Επίσης, παρασκευάστηκαν 6 blended τσιμέντα, με ανάμιξη με BC, BC5 και BC10 σε διάφορα ποσοστά, με OPC_42.5Ν. Τα blended τσιμέντα έδωσαν βελτιωμένες συνολικά αντοχές. Οι πρώιμες αντοχές παρουσίαζαν μικρή μείωση σε σχέση με το OPC_42.5N. Ελέγχθηκε κατά πόσο το τελικό προϊόν που παράγεται μέσω της πειραματική-εργαστηριακής διαδικασία αποκλίνει ποιοτικά από αυτό που έχει προέλθει από την βιομηχανική παραγωγική διαδικασία, και τα αποτελέσματα ήταν ικανοποιητικά. Όσον αφορά τις βιομηχανίες τσιμέντου και χάλυβα, η παραγωγή μπελιτικών τσιμέντων με παράλληλη αξιοποίηση σκωρίας ως Α! ύλη συνεπάγεται κέρδος τόσο περιβαλλοντικό όσο και οικονομικό. Συνολικά κατά την παραγωγή τους απαιτείται λιγότερη ενέργεια, εκπέμπεται μικρότερη ποσότητα CO2 και η ζήτηση σε πρώτες ύλες είναι επίσης μειωμένη. Η μελέτη της περιβαλλοντικής συμπεριφοράς των BC5 και BC10 τσιμέντων, πραγματοποιήθηκε με βάση το πρότυπο NEN 7345-tank test που αναφέρεται σε μονολιθικά υλικά. Τα αποτελέσματα δείχνουν ότι στην περίπτωση του V δεν ανιχνεύεται καμία μετρήσιμη εκλουόμενη ποσότητα για τα δύο δοκίμια ενώ στην περίπτωση του Cr η συνολική έκλουση που καταγράφεται μετά από 64 ημέρες είναι 78.72 mg/m2 για το BC5 και 113.81 mg/m2 για το BC10. Οι τιμές του εκλουόμενου Cr και για τα δυο δοκίμια, δεν υπερβαίνουν το όριο Existing (NEN7375) Monolithic Waste Acceptance Criteria_mg/m2 at 64 days (500 mg/m2), σύμφωνα με τον moWaC. Ο προσδιορισμός του μηχανισμού που οδηγεί στην απελευθέρωση χρωμίου για τα δοκίμια προσδιορίστηκε ότι είναι διάχυση. / In the present work studied the valorization of the electric arc furnace slag (Electric Arc Furnace Slag-EAFS), as raw material in the production of belite cement. The electric arc furnace slag (EAF) is a byproduct of the metallurgical industry, resulting from melting in electric arc furnace ferrous scrap. According to the American Society for Testing Materials (ASTM), the slag is defined as a non-metallic product. The slag is a molten phase consisting mainly of calcium silicate compounds joined together with oxides of iron, aluminum, calcium and magnesium and is produced simultaneously with steel in a furnace. The quantity of slag produced in steel industries, as a byproduct of the production process, represents approximately 13% - 18% of the total quantity supplied to the furnace so that the metallurgical slag is one of the major industrial products in quantity. As a result, steel industries are facing problems with the deposition and disposal of the slag and the environmental impacts arising from them. The scientific interest over the last 20 years was turned to the production of belite cements, which present low firing temperature and CO2 emission. This type of cement, unlike conventional OPC, contains a higher percentage of belite (C2S) and a lower percentage of alite (C3S), result of low firing temperature (~1350°C) which classifies them in the category of environmentally friendly cements. Additionally, the valorization of industrial byproducts, as raw materials, which present chemical composition suitable for cement production, leads to partial reduction of raw materials demand and CO2 emissions, as they constitute source of CaO by reducing the need for decarbonation of CaCO3. The valorization of EAF slag as raw material in the producing of belite cement was studied. The raw materials used to prepare the mixtures were limestone, clay and EAF slag. The EAF slag derived from the steel industry «SOVEL» (subsidiary of "Sidenor") which annual production of steel is 750 kt while EAF slag is 97.5 kt. Their chemical analysis was performed by X-ray fluorescence spectrometry (XRF, Philips PW 2400). The crystalline phases of the raw materials were identified by X-ray diffraction analysis (D5000 Siemens). Qualitative analysis was performed by the DIFFRACplus EVA® software (Bruker-AXS) based on the ICDD Powder Diffraction File. The mineral phases were quantified using a Rietveld-based quantification routine with the TOPAS® software (Bruker-AXS). The slag was characterized by SEM/EDS micro-analysis, results shown that was appropriate to partially substitute the raw materials in cement production. Four types of clinker produced with 0w.t.% (BC), 5 w.t.% (BC5), 10 w.t.% (BC10) and 20 w.t.% (BC20) EAF slag, aimed at maintaining high belite (> 55%) levels. The firing temperature of the clinker was at 1380ºC. The firing temperature was determined by preliminary burnability tests at the temperature range of 1280°C-1400°C, based on the results of free lime content and the microstructure evolution. The microstructure of the produced clinker consisting mainly of belite and alite crystals, while the (C3A + C4AF) is presented as an interstitial phase around the crystals with micro-crystalline structure. The produced cements present low early strength. However, the strength results of 28 days for BC, BC5, BC10 and BC20 are 47.5 MPa, 46.6 MPa, 42.8 MPa and 35.5 MPa respectively, meet the conditions for integration into the category OPC CEMI 32.5N, according to EN 197-1. Also observed that the BC10 and BC20 behave as ‘‘flash-set’’ cements. The expansion (soundness) was measured 1mm for all the samples. The results show that the EAF slag could be used for the production of such cements, which disadvantage in the development of early strength towards OPC. Moreover, 6 blended cements prepared by mixing BC, BC5 and BC10 at different proportions, with OPC_42.5N. The blended cements provided improved overall strength. The early strength showed a slight decrease compared with OPC_42.5N. Was examined the qualitative difference of the cement which was produced by laboratory-experimental procedure with the one from the industrial production process, the results were satisfactory. With regard to cement and steel industries, belite cements production with parallel valorization of EAF slags as raw material implies both environmental and energy profits. Overall their production requires less energy, less amount of CO2 emitted and also the demand of raw materials is reduced. The study of the environmental behavior of BC5 and BC10 cement, carried out according to the NEN 7345-tank standard test referred to monolithic materials. The results showed no V release, while the release of Cr increased according with the increment of the slag content. The total leached quantity after 64 days is 78.72 mg/m2 for BC5 and 113.81 mg/m2 for BC10. The values of the leachate Cr for both samples, not exceeding the limit of Existing (NEN7375) Monolithic Waste Acceptance Criteria_mg/m2 at 64 days (500 mg/m2). The determination of the mechanism leading to the release of chromium samples, determined to be diffusion.

A injeção de carvão pulverizado na região das ventaneiras dos altos-fornos (Pulverized Coal Injection – PCI) é uma tecnologia amplamente praticada em altos-fornos com o objetivo de substituir parte do coque empregado por carvões não-coqueificáveis. O carvão injetado fornece energia e gases redutores para o processo de fabricação do gusa, além de contribuir para a redução da emissão de gases poluentes devido à menor produção de coque. Atualmente todo o carvão injetado em altos-fornos brasileiros é importado. O país possui grandes reservas de carvão, porém este carvão necessita passar por processos de beneficiamento para redução dos teores de matéria mineral e enxofre. A flexibilidade do processo PCI permite a utilização de ampla gama de carvões não-coqueificáveis, o que abre a possibilidade para utilização de carvão brasileiro. Este trabalho teve por objetivo avaliar propriedades de carvão brasileiro beneficiado com teor de cinzas de 18,9% para injeção em altos-fornos. O estudo foi conduzido através de ensaios de combustão empregando um moderno simulador de PCI projetado e desenvolvido pelo Laboratório de Siderurgia da Universidade Federal do Rio Grande do Sul (LaSid) e também uma termobalança de modo a ser possível traçar um comparativo entre ambos os equipamentos. Além do carvão brasileiro, de baixo rank, foram utilizados dois carvões importados já em uso para injeção, um de alto e um de baixo rank. A combustibilidade (ou eficiência de combustão) em simulador de PCI foi avaliada pela conversão (burnout), calculada pelo método ash tracer, um balanço de massa entre a quantidade de cinzas que entra e sai do reator. Em termobalança o parâmetro adotado foi a temperatura de pico, correspondente à taxa máxima de reação. Fez-se também a avaliação da reatividade ao CO2 dos chars gerados em simulador de PCI, visto que o char ao deixar a zona de combustão passa por uma zona rica neste gás. Análise estatística revelou que a técnica adotada de burnout mostrou-se bastante eficiente para diferenciar carvões de teores de matéria volátil distintos, porém não no caso de carvões com teores de matéria volátil similares. No simulador de PCI a influência da matéria volátil do carvão foi mais pronunciada do que o rank e em termobalança o rank teve mais efeito sobre a combustibilidade do que a matéria volátil. O carvão brasileiro apresentou propriedades comparáveis às do carvão importado de baixo rank utilizado para PCI. Isto representa uma grande vantagem, visto que possibilitaria a utilização do mesmo na siderurgia. / Pulverized coal injection through blast furnace tuyeres (PCI) is a widely practiced technology in blast furnaces to replace part of coke by non-coking coal. Injected coal provides energy and reducing gases for pig iron production process, as well as contributes to reducing pollutants gases emission due to coke saving. Currently all coal injected into Brazilian blast furnaces is imported. The country has large reserves of coal, but this coal needs to undergo beneficiation to reduce mineral matter and sulfur contents. PCI process flexibility allows the employment of a wide range of non-coking coals, which opens the possibility to use Brazilian coal. This work aimed to evaluate properties of Brazilian coal benefited with 18.9% ash content for injection into blast furnaces. The study was conducted through combustion tests employing a modern PCI test rig designed and developed by the Iron and Steelmaking Laboratory (LaSid) of the Federal University of Rio Grande do Sul (UFRGS) and also a thermobalance in order to draw a comparison between both equipments. In addition to low rank Brazilian coal, two imported coals which are already used for injection were used, one high and one low rank. The combustibility (or combustion efficiency) in a PCI test rig was evaluated by burnout, calculated by the ash tracer method, a mass balance between the amount of ash that enters and leaves the reactor. Peak temperature was the parameter adopted to evaluate combustibility in thermobalance, corresponding to the maximum rate of reaction. It was also evaluated the CO2 reactivity of chars generated in the PCI test rig, since char leaving the combustion zone passes through a CO2 rich area. Statistical analysis revealed that burnout technique proved to be efficient enough to differentiate coals with different volatile matter contents, but not in the case of coals with similar volatile matter contents. In PCI test rig the influence of volatile matter was more pronunced than rank and in thermobalance rank had more effect on combustibility than volatile matter. Brazilian coal showed properties comparable to the ones of imported low rank coal already in use for PCI. This is a great advantage, since it would make it possible to use it in ironmaking.