WO2018099558A1 - Boulettes de minerai métallique - Google Patents

Boulettes de minerai métallique Download PDF

Info

Publication number
WO2018099558A1
WO2018099558A1 PCT/EP2016/079337 EP2016079337W WO2018099558A1 WO 2018099558 A1 WO2018099558 A1 WO 2018099558A1 EP 2016079337 W EP2016079337 W EP 2016079337W WO 2018099558 A1 WO2018099558 A1 WO 2018099558A1
Authority
WO
WIPO (PCT)
Prior art keywords
pellets
fluxed pellets
ore fluxed
weight
crude
Prior art date
Application number
PCT/EP2016/079337
Other languages
English (en)
Inventor
Eduardo DA COSTA
Original Assignee
S.A. Lhoist Recherche Et Developpement
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by S.A. Lhoist Recherche Et Developpement filed Critical S.A. Lhoist Recherche Et Developpement
Priority to PCT/EP2016/079337 priority Critical patent/WO2018099558A1/fr
Publication of WO2018099558A1 publication Critical patent/WO2018099558A1/fr

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B1/00—Preliminary treatment of ores or scrap
    • C22B1/14—Agglomerating; Briquetting; Binding; Granulating
    • C22B1/24—Binding; Briquetting ; Granulating
    • C22B1/2406—Binding; Briquetting ; Granulating pelletizing
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B1/00—Preliminary treatment of ores or scrap
    • C22B1/14—Agglomerating; Briquetting; Binding; Granulating
    • C22B1/24—Binding; Briquetting ; Granulating
    • C22B1/242—Binding; Briquetting ; Granulating with binders
    • C22B1/243—Binding; Briquetting ; Granulating with binders inorganic

Definitions

  • the present invention relates to metallic ore fluxed pellets, in particular iron ore fluxed pellets.
  • metal ore fluxed pellets 1 ' pellets made from metallic ore coming from metal ore mines.
  • metallic is a general term which includes the ferrous, also called iron, and the non-ferrous metal ore.
  • the non-ferrous metal ore commonly contains metals such as chromium, manganese, nickel, lead, tin, copper, etc.
  • the iron (ferrous) ore mainly contains iron, about 60% by weight or above, but may also contain other metals such as titanium and manganese in combination with iron.
  • Metallic ore pellets are produced from fine metallic concentrate containing at least 60 % by weight of metals.
  • Metallic ore concentrate also simply called concentrate, is the product obtained by finely grinding raw ore in a grinding operation after which the gangue (impurities) is removed. The resulting product is therefore a concentrate of metal component.
  • the remaining impurities which can be present in the concentrate are for example silicates, aluminates, phosphates, sulphates.
  • Iron ore pellets are made from magnetitic, hematitic, limonitic sideritic concentrates containing at least 60% by weight of iron.
  • the fine metallic concentrate is firstly granulated in a vessel (container) like a drum or a disk (pan) during a balling process, to form the so-called green pellets which are in fact crude pellets. These green pellets are then hardened by heating in an induration furnace which is typically divided in three zones; the drying zone at about 300°C, the firing zone at about 1300 °C and the cooling zone. After the hardening process, the pellets may be called fired pellets and are suitable for handling in bulk and charging into a metallurgical reactor, for example a blast furnace (shortened BF) or a direct reduction reactor (shortened DR), the direct reduction reactor being used before an electric arc furnace in a plant.
  • a metallurgical reactor for example a blast furnace (shortened BF) or a direct reduction reactor (shortened DR), the direct reduction reactor being used before an electric arc furnace in a plant.
  • fluxes also called fluxing agents
  • the metallic ore pellets containing fluxes are also called metallic ore fluxed pellets or just fluxed pellets.
  • the properties of the fluxed pellets depend on the nature of the above fluxes which are physically and chemically different and which contain different types and quantities of gangue materials, such as silica and/or alumina, etc. which are considered as impurities in the pellets.
  • Binders are used in the production of fluxed pellets in order to allow the formation of the green pellets by balling and then withstand the mechanical and thermal stresses of the handling in their production process in particular in the induration furnace (in the drying, firing and cooling zones).
  • Bentonite a type of clay, has been the binder of choice since the inception of the production of metallic ore fluxed pellets.
  • An existing alternative to the bentonite is the use of organic binders like those based on carboxymethylcellulose or polyacrylamide, which are however more expensive and hinder the achievement of good mechanical properties in the final pellets.
  • the present invention aims at focusing on the use of alternative binders for the manufacturing of metallic ore fluxed pellets, in particular iron ore fluxed pellets.
  • J. Pan et al. relates to the production in laboratory of calcitic fluxed pellets made from the mix of pre-treated iron fine ore, binder and limestone as fluxes (see Iron Ore conference / Perth, WA, 11-13 July 2011 , J Pan, D Q Zhu, M Emrich, T J Chun and H Chen, "Improving the fluxed pellets performance by hydrated lime instead of bentonite as binder").
  • the binders which are compared in this document are bentonite and hydrated lime and the mechanical properties of the resulting fluxed pellets are analysed. This document concludes that the replacement of bentonite by hydrated lime as binder improves the physical properties and the compressive strength of fired pellets and also plays a role in improving the metallurgical performance of fired pellets.
  • the preheating temperature during the induration process of the green pellets has to be controlled and brought up to 1100 °C.
  • the compressive strength of the fired pellets made from preheated pellets with bentonite is higher than the one of those made from preheated pellets containing hydrated lime when the preheating temperature was less than 1050 °C.
  • the document of Gielen relates to the industrial production of pellets made from hematitic concentrate (see Society of mining engineers of aime, Colorado, 1983, "Quality improvements and energy savings in iron ore pelletizing" by H.H. Gielen, H.S. Heep, . R. Hohensee, H. G. Papacek, V. V. Arnim).
  • hydrated lime is by no means a good substitute for bentonite as a binder in fluxed pellets.
  • Green pellets containing hydrated lime as a binder had a strong tendency to stick, causing a lot of difficulties with clogged screen decks. They highlighted that, with improvements achieved in the filter section (filter cake) during a filtration step of the fine concentrates and at the same time a partial substitution of hydrated lime by limestone in the composition of the green pellets, the difficulties during the balling step were reduced.
  • bentonite turned out to be the binder of choice in the production of fluxed pellets notably because it enhances the balling process by controlling the moisture content of the green pellets. Indeed, the balling process and more precisely the balling rate is, amongst others, controlled by the moisture content of the raw mixture used to produce green pellets. Bentonite has been found to more easily regulate the moisture content during the balling process. However, although bentonite seems to be inescapable for producing metallic fluxed pellets with good physical properties, it presents the drawback of bringing more impurities, mainly silica and alumina, to the green pellets.
  • impurities withstand the induration process and can be found in the fired pellets.
  • the addition of impurities such as silica or alumina to the fired pellets causes thereafter the increase of the amount of slag in the metallurgical furnace (notably the blast furnace or the electric arc furnace) which is not desirable.
  • the present invention further relates to metallic ore fluxed pellets, in particular iron ore fluxed pellets containing a calcium magnesium compound as binder.
  • the basicity of the fired pellets has to be controlled by controlling the fraction between Ca and/or Mg compounds expressed as oxides (CaO and/or MgO) on the one side and S1O 2 and/or AI2O 3 on the other side.
  • the quantity of these compounds is however governed by the chemical composition of the green pellets which is itself controlled by the composition of the compounds initially used for producing them.
  • Metallic fluxed pellets have to fulfill critical criteria to be used in metallurgical reactors, such as blast furnace or direct reduction reactor.
  • the mechanical and metallurgical properties of the fired pellets need to be adequate, for example, for avoiding decrepitation or swelling at high temperatures inside the metallurgical reactor.
  • the green (crude] pellets also have to present adequate physical properties to resist to the hardening process without being degraded by the increase of the temperature and the compression constraints into the induration furnace.
  • the ratio between the solid components and the water added during the balling process is crucial for having pellets with the right size, as well as presenting a good behavior in the next steps of the process, especially inside the induration furnace.
  • the ratio between the different components in the starting powdered composition are therefore crucial for processing green pellets presenting the appropriate physicochemical properties during the induration process as well as later on in the form of fired pellets, inside the metallurgical reactors.
  • the resulting fired pellets have also to present satisfactory physical and metallurgical properties to be used afterwards in metallurgical reactors.
  • the physical properties are essential for example because breakage and abrasion of the fired pellets lead to the loss of material during their storage and transportation. Moreover, it is preferable for the fired pellets to present a good mechanical strength, also called crushing or compressive strength, in order to avoid any loss of permeability in the metallurgical reactor when charged into it.
  • the mechanical strength of the pellets can be measured, for example by the ISO standard 4700, "Determination of the crushing strength".
  • the metallurgical qualities of the fired pellets are also an important criterion which is characterized by the reducibility, the swelling and the low temperature breakdown of the fired pellets, notably according to the ISO standard 7215, “Determination of the reducibility by the final degree of reduction index” or according to standard ISO 4695 “Determination of the reducibility by the rate of reduction index”, the ISO standard 4698, “Determination of the free-swelling index” and the ISO standard 4696 “Determination of low-temperature reduction-disintegration indices by static method”.
  • bentonite is at the moment recommended to achieve all the above mentioned requirements essential to obtain adequate metallic fluxed pellets suitable for withstanding an induration process when in the form of green pellets and thereafter for use in direct reduction reactors or blast furnaces when in the form of fired pellets.
  • the invention provides the use of a calcium magnesium compound as binder for producing metallic ore fluxed pellets, in particular iron ore fluxed pellets characterized in that the calcium magnesium compound is fitting the general formula aCa(OH)2.bMg(OH) 2 .c g0.dCa0.eCaC0 3 .flv1gC03 ) a, b, c, d, e and f being weight fractions comprised between 0 % and 100 % by weight with respect to the total weight of said calcium magnesium compound.
  • This compound is a dolomite or dolomitic limestone derivative, which will also be called a calcium magnesium compound in the present invention, obtained by calcination and then by partial hydration (slaking with water) of a natural dolomite or dolomitic limestone.
  • the calcium magnesium compound may therefore contain the same impurities than those of the dolomite from which it is produced.
  • Calcium magnesium compound according to the present invention may so contain impurities, such as sulphur oxide, SO 3 , silica, Si0 2 or even alumina, AI2O3, the sum of which being at a level of some weight %.
  • impurities such as sulphur oxide, SO 3 , silica, Si0 2 or even alumina, AI2O3, the sum of which being at a level of some weight %.
  • the impurities are expressed herein under their oxide form, but of course, they might appear as different minerals.
  • the present invention describes the use not of physical mixtures but actually of a single compound providing both magnesium and calcium compounds.
  • the use of a single compound instead of physical mixtures of multiple compounds has a considerable practical advantage, since the method for producing the pellets will be easier when a single binder is used instead of several ones. Further, the homogeneity of the dispersion of the Ca and Mg compounds in the composition of the pellets is also improved when both of these components are provided via a single binder, itself perfectly homogenous.
  • calcium magnesium compound is used as a binder in order to let the metallic ore fluxed pellets to be formed properly and to withstand the induration process, giving afterwards fired pellets of good quality, meaning having good mechanical and metallurgical properties.
  • calcium magnesium compound used as binder in the present invention allows to control the moisture content of the composition during the process of production of green pellets and to enhance the mechanical properties of the resulting green pellets.
  • Another advantage of the use of calcium magnesium compound as a binder leads to a decrease in the consumption of carbonates as a flux, if they are used, causing a decrease in the C0 2 emissions during the induration process.
  • the calcium magnesium compound according to the present invention when the calcium magnesium compound according to the present invention is replacing silicates-including compounds, it allows the reduction of the slag-rate in the blast-furnace.
  • the weight ratio of said binder is between 0.5 % and 5 %, preferably between 0.5 % and 1.5 % by weight with respect to the total weight of the pellets.
  • the weight fraction of calcium magnesium compound is between 70 % and 100 %, preferably between 75 % and 100 %, more preferably between 80 % and 100 %, advantageously between 85 % and 100 %, preferably between 90 % and 100 % by weight with respect to the total weight of the binder.
  • the calcium magnesium compound is 100% by weight with respect to the total weight of the binder.
  • the calcium magnesium compound is in a powdery form.
  • the calcium magnesium compound is in the form of an aqueous suspension of said compound based on said calcium magnesium compound.
  • the calcium magnesium compound comprises particles presenting BET specific surface area obtained from nitrogen adsorption comprised between 5 and 25 m 2 /g, in particular between 10 m 2 /g and 20 m 2 /g.
  • particles in the sense of the present invention, it is meant the smallest solid discontinuity of the mineral filler which may be observed with a scanning electron microscope (SEM).
  • BET specific surface area it is meant in the meaning of the present specification the specific surface area measured by manometry with adsorption of nitrogen at 77 K after degassing under vacuum at a temperature comprised between 150 and 250°C, notably at 190°C for at least 2 hours and calculated according to the multipoint BET method as described in the ISO 9277:2010E standard.
  • the calcium magnesium compound comprises particles presenting a total BJH pore volume consisting of pores with a diameter lower than 000 A, obtained from nitrogen desorption comprised between 0.05 and 0.15 cm 3 /g.
  • BJH pore volume the pore volume as measured by manometry with adsorption of nitrogen at 77 K after degassing under vacuum at a temperature comprised between 150 and 250°C, notably at 190°C for at least 2 hours and calculated according to the BJH method, using the desorption curve, with the hypothesis of a cylindrical pore geometry.
  • total pore volume in the present specification, it is meant the BJH pore volume consisting of pores with a diameter smaller than or equal to 1000 A.
  • the calcium magnesium compound comprises particles presenting a d-i 0 greater or equal to 0.5 ⁇ , in particular about 1 pm.
  • the calcium magnesium compound comprises advantageously particles presenting a dso comprised between 4 pm and 8 pm.
  • the calcium magnesium compound comprises particles presenting a dg 7 comprised between 40 pm and 95 pm.
  • the notation dx represents a diameter expressed in pm, measured by laser granulometry in methanol after sonication, relatively to which X % by volume of the measured particles are smaller or equal.
  • the metallic ore fluxed pellets in particular iron ore fluxed pellets, contain metallic ore concentrate, in particular iron ore concentrate, presenting particles having a Blaine fineness comprised between 1500 cm 2 /g and 2500 cm 2 /g, preferably between 1800 cm 2 /g and 2200 cm 2 /g.
  • Blaine fineness it is meant in the meaning of the present specification fineness measured according to the ASTM standard C-204-07 using an air-permeability apparatus and the Test Method A.
  • the Blaine fineness of particles is the specific surface area expressed as the surface area in square centimetres per gram of particles.
  • the metallic ore fluxed pellets in particular iron ore fluxed pellets, present a size distribution characterized by 90% to 98 % of the pellets presenting a diameter comprised between 8 to 16 mm.
  • metallic ore fluxed pellets are iron ore fluxed pellets comprising fine iron ore concentrate selected from the group consisting of magnetite, hematite and mixture thereof.
  • the metallic ore fluxed pellets in particular the iron ore fluxed pellets further comprise a flux selected from the group consisting of calcium carbonate, dolomite, olivine, pyroxenite, other magnesium silicates, like dunite, and mixture thereof.
  • said flux is between 0.5 % and 15 % by weight with respect to the total weight of the pellets.
  • the metallic ore fluxed pellets in particular the iron ore fluxed pellets are crude metallic ore fluxed pellets, in particular crude iron ore fluxed pellets.
  • the moisture content of the pellets is controlled, even in the absence of bentonite, and the mechanical and metallurgical properties of the pellets are enhanced.
  • the crude metallic ore fluxed pellets are characterized by a crushing strength before drying (“wet pellet”) which is comprised between 10 and 30 N per pellet and after drying (“dried pellet”) which is comprised between 30 and 90 N per pellet .
  • the crude metallic ore fluxed pellets according to the present invention present a shock temperature equal to or more than 250 °C.
  • shock temperature it is meant according to the present invention the minimum temperature at which cracks are produced in the wet crude pellets when put inside a hot muffle, directly from room temperature.
  • various samples of crude pellets are submitted individually to gradually increased temperature. Typically, a first sample will be subject to 200°C, the second to 250°C..., until cracked pellets are observed in one sample. Those cracks appear very quickly ( a few minutes) in the pellets after submission to the setting temperature.
  • the metallic ore fluxed pellets, in particular the iron ore fluxed pellets according to the present invention are fired metallic ore fluxed pellets, in particular fired iron ore fluxed pellets.
  • the fired pellets presents also enhanced mechanical properties after the hardening process.
  • the crushing strength of the fired pellets according to the present invention measured according to standard ISO 4700 is comprised between 2000 and 5000 N/pellet.
  • the quality of the fired pellets according to the present invention has been enhanced since the replacement of the minerals contained in the bentonite allows for example the reduction of the volume of slag in the blast-furnace or electric arc furnace after the direct reduction reactor.
  • the fired pellets according to the invention contain less than 10 %, in particular less than 5% by weight of S1O 2 with respect to the total weight of the pellets.
  • the total metal, in particular iron, content in the fired pellets is preferably equal to or higher than 55 %, in particular equal to or higher than 60%, advantageously equal to or higher than 65% by weight with respect to the total weight of the pellets.
  • the metallurgical properties of the fired pellets obtained according to the present invention are a reducibility above 0.70 %/minute, following the standard ISO 4695, “Determination of the reducibility by the rate of reduction index”, below 20% swelling (by buoyancy), following the standard ISO 4698, “Determination of the free-swelling index” and a crushing strength after reduction above 150 N/peliet, following the standard ISO 4696 "Determination of low-temperature reduction-disintegration indices by static method Ltd.
  • the invention relates also to a process for manufacturing metallic ore fluxed pellets, in particular iron ore fluxed pellets comprising the steps of:
  • said binder is a calcium magnesium compound fitting the general formula aCa(OH) 2 .bMg(OH) 2 .cMgO.dCaO.eCaCO 3 .fMgC0 3l a, b, c, d, e and f being weight fractions comprised between 0 % and 100 % by weight with respect to the total weight of said calcium magnesium compound.
  • the balling and the sieving step is preferably performed in a granulating vessel like a drum or disk (pan) which can be the container or not.
  • the residence time of the wet mixture to form the pellets inside the granulating drum is comprised between 50 and 200 s for pellets presenting a diameter comprised between 8 and 16 mm.
  • the process according to the present invention further comprises the step of hardening the crude metallic ore fluxed pellets, in particular crude iron ore fluxed pellets in an induration furnace.
  • Said hardening step comprises advantageously the steps of : - drying the crude pellets at about 300°C during a predetermined duration comprised between 5 min and 15 min for forming dried crude pellets;
  • pre-heated crude pellets at a temperature equal to or higher than 1200°C during a predetermined duration comprised between 5 min and 20 min to form fired metallic ore fluxed pellets, in particular fired iron ore fluxed pellets;
  • the step of adjusting moisture is a step of adding an aqueous phase to form said wet mixture.
  • the step of adding an aqueous phase is preferably a gradual addition of the aqueous phase into the powdered mixture.
  • the aqueous phase is water.
  • the step of adjusting moisture is performed until said mixture presents a moisture content comprised between 5 % et 15% by weight with respect to the total weight of said mixture.
  • crude metallic ore fluxed pellets in particular crude iron ore fluxed pellets present a size distribution characterized by 90% to 98 % of the pellets presenting a diameter comprised between 8 to 16 mm.
  • the process according to the invention further comprises a step of feeding a flux before the step of adjusting moisture, the flux being preferably selected from the group consisting of calcium carbonate, olivine, pyroxenite, other magnesium silicates and mixture thereof.
  • the binder is added in a quantity comprised between 0.5 % and 5 %, preferably between 0.5 % and 1.5 % by weight with respect to the total weight of the pellets.
  • the weight fraction of calcium magnesium compound is between 80 % and 100 %, preferably between 90 % and 100 %, more preferably between 95 % and 100 %, advantageously between 97 % and 00 %, preferably between 98 % and 100 % by weight with respect to the total weight of the binder.
  • the calcium magnesium compound is 100% by weight with respect to the total weight of the binder.
  • said fine metallic ore concentrate in particular iron ore concentrate presents advantageously a Blaine fineness comprised between 1500 cm 2 /g and 2500 cm 2 /g, preferably between 1800 cm 2 /g and 2200 cm 2 /g.
  • the present invention relates also to a metallic ore fluxed pellets, in particular iron ore fluxed pellets composition
  • a metallic ore fluxed pellets in particular iron ore fluxed pellets composition
  • iron ore fluxed pellets composition comprising:
  • a fine metallic ore concentrate in particular an iron ore concentrate in a quantity comprised between 80 weight % and 99 weight % with respect to the total weight of the metallic ore fluxed pellets composition;
  • a calcium magnesium compound as binder in a quantity comprised between 0.1 weight % and 5 weight %, in particular between 0.5 weight % and 1.5 weight % with respect to the total weight of the metallic ore fluxed pellets composition;
  • the calcium magnesium compound is fitting the general formula aCa(OH) 2 .bMg(OH)2.cMg0.dCa0.eCaC0 3 .fMgC0 3 , a, b, c, d, e and f being weight fractions comprised between 0 % and 100 % by weight with respect to the total weight of said calcium magnesium compound.
  • the weight fraction of calcium magnesium compound is between 80 % and 100 %, preferably between 90 % and 100 %, more preferably between 95 % and 100 %, advantageously between 97 % and 100 %, preferably between 98 % and 100 % by weight with respect to the total weight of the binder.
  • the calcium magnesium compound is 100% by weight with respect to the total weight of the binder.
  • composition according to the invention further comprises from 0.5 weight% to 15 weight % of additives as fluxes with respect to the total weight of the metallic ore fluxed pellets composition.
  • the calcium magnesium compound comprises particles presenting BET specific surface area obtained from nitrogen adsorption comprised between 5 and 25 m 2 /g, preferably between 10 m 2 /g and 20 m 2 /g.
  • the calcium magnesium compound of the composition according to the invention comprises particles presenting a total BJH pore volume consisting of pores with a diameter lower than 1000 A, obtained from nitrogen desorption comprised between 0.05 and 0.15 cm 3 /g.
  • the calcium magnesium compound comprises particles presenting a size characterized either by a dio equal to or greater than 0.5 pm, and/or a d 50 comprised between 4 pm and 8 pm, and/or a d ⁇ 7 comprised between 40 pm and 95 pm.
  • the metallic ore concentrate in particular iron ore concentrate presents particles having a Blaine fineness comprised between 1500 cm 2 /g and 2500 cm 2 /g, preferably between 1800 cm 2 /g and 2200 cm 2 /g.
  • the fine iron ore concentrate is selected from the group consisting of magnetite, hematite and mixture thereof.
  • the composition according to the invention further comprises a flux selected from the group consisting of calcium carbonate, dolomite, olivine, pyroxenite, other magnesium silicates, like dunite, and mixture thereof.
  • the present invention relates also to crude metallic ore fluxed pellets, in particular crude iron ore fluxed pellets comprising:
  • a fine metallic ore concentrate in particular an iron ore concentrate in a quantity comprised between 80 weight % and 99 weight % with respect to the total weight of the crude metallic ore fluxed pellets;
  • a calcium magnesium compound as binder in a quantity comprised between 0.1 weight % and 5 weight %, in particular between 0.5 weight % and 1.5 weight % with respect to the total weight of the crude metallic ore fluxed pellets;
  • a moisture content comprised between 5 weight % and 15 weight % with respect to the total weight of the crude metallic ore fluxed pellets ;
  • the calcium magnesium compound is fitting the general formula aCa(OH)2.bMg(OH)2.cMgO.dCaO.eCaCO 3 .fMgCO 3 , a, b, c, d, e and f being weight fractions comprised between 0 % and 100 % by weight with respect to the total weight of said calcium magnesium compound, said crude metallic ore fluxed pellets.
  • the weight fraction of calcium magnesium compound is between 80 % and 100 %, preferably between 90 % and 00 %, more preferably between 95 % and 100 %, advantageously between 97 % and 100 %, preferably between 98 % and 100 % by weight with respect to the total weight of the binder.
  • the calcium magnesium compound is 100% by weight with respect to the total weight of the binder.
  • said crude iron ore fluxed pellets further presenting a crushing strength comprised between 10 and 30 N/pellet.
  • the crude metallic ore fluxed pellets in particular crude iron ore fluxed pellets further comprises from 0.5 weight% to 15 weight % of additives as fluxes with respect to the total weight of the crude metallic ore fluxed pellets.
  • the crude metallic ore fluxed pellets in particular the crude iron ore fluxed pellets present a shock temperature equal to or higher than 250 °C.
  • said crude metallic ore fluxed pellets in particular said crude iron ore fluxed pellets further present a crushing strength between 30 and 90 N/ pellet after drying.
  • the crude pellets present a crushing strength comprised between 10 and 30 N/pellet before drying, when they are crude wet pellets, and present a crushing strength between 30 and 90 N/ pellet after drying, when they are crude dried pellets.
  • the drying step is performed at about 105°C during a predetermined duration typically comprised between 12h and 24h.
  • the crude metallic ore fluxed pellets in particular crude iron ore fluxed pellets according to the invention present a size distribution wherein 90% to 98 % of the pellets presents a diameter comprised between 8 to 16 mm.
  • the crude metallic ore fluxed pellets in particular crude iron ore fluxed pellets according to the invention comprise advantageously fine iron ore concentrate selected from the group consisting of magnetite, hematite and mixture thereof.
  • the crude metallic ore fluxed pellets, in particular crude iron ore fluxed pellets according to the invention further comprise a flux selected from the group consisting of calcium carbonate, dolomite, olivine, pyroxenite, other magnesium silicates, like dunite, and mixture thereof.
  • the crude pellets according to the invention contain metallic ore concentrate, in particular iron ore concentrate presenting particles having a Blaine fineness comprised between 1500 cm 2 /g and 2500 cm 2 /g, preferably between 1800 cm 2 /g and 2200 cm 2 /g.
  • the present invention relates also to fired metallic ore fluxed pellets, in particular fired iron ore fluxed pellets comprising:
  • the pellets present a Ca/Mg ratio between 0.8 and 2, in particular between 0.8 and 1.7, most particularly between 0.8 and 1.2 and present a crushing strength measured according to standard ISO 4700 comprised between 2000 and 5000 N/pellet, preferably comprised between 2500 and 5000 N/pellet.
  • said fired metallic ore fluxed pellets in particular fired iron ore fluxed pellets contain less than 10 %, in particular less than 5% by weight of S1O2 with respect to the total weight of the pellets.
  • the fired metallic ore fluxed pellets in particular fired iron ore fluxed pellets according to the invention comprise advantageously fine iron ore concentrate selected from the group consisting of magnetite, hematite and mixture thereof.
  • the fired metallic ore fluxed pellets, in particular fired iron ore fluxed pellets according to the invention further comprise a flux selected from the group consisting of calcium carbonate, dolomite, olivine, pyroxenite, other magnesium silicates, like dunite, and mixture thereof.
  • the fired metallic iron ore fluxed pellets in particular fired iron ore fluxed pellets present a size distribution wherein 90% to 98 % of the pellets presents a diameter comprised between 8 to 16 mm.
  • fired metallic ore fluxed pellets in particular fired iron ore fluxed pellets according to the invention are mentioned in the annexed claims.
  • a composition containing the binder according to the invention has been implemented and present the characteristics presented in table 1.
  • the weight % are expressed with respect to the total weight of the pellets.
  • Water is added to composition according to table 1 in order to ball and sieve the resulting wet mixture into crude pellets.
  • the crude pellets are dried at about 300°C for forming dried crude pellets.
  • the dried crude pellets are pre-heated at 800°C for forming pre-heated crude pellets.
  • the pre-heated crude pellets are fired at 1280°C to form fired pellets.
  • the total cycle time from the drying step to the end of the firing step is 22.4 minutes and the bed height green balls/hearth layer is 300/100 mm.
  • the fired pellets present 64.2 weight % of Fe and 4.2 weight % of S1O 2 based on the total weight of the fired pellets.
  • the crushing strength of the fired pellets measured according to the standard ISO 4700 is 3320 N/pellet.
  • the fired pellets are subjected to a swelling test according to standard ISO 4698 and afterwards the crushing strength of the pellets is measured according to the standard ISO 4700.
  • the fired pellets are subjected to a reducibility test according to standard ISO 4695 and afterwards the crushing strength of the pellets is measured according to the standard ISO 4700.
  • the fired pellets are subjected to a desintegration test according to standard ISO 4696 and afterwards the crushing strength of the pellets is measured according to the standard ISO 4700.
  • Water is added to composition according to table 3 in order to ball and sieve the resulting wet mixture into crude pellets.
  • the crude pellets are dried at about 300°C for forming dried crude pellets.
  • the dried crude pellets are pre-heated at 800°C for forming pre-heated crude pellets.
  • the pre-heated crude pellets are fired at 1280°C to form fired pellets.
  • the total cycle time from the drying step to the end of the firing step is 22.4 minutes and the bed height green balls/hearth layer is 300/100 mm.
  • the fired pellets present 63.7 weight % of Fe and 3.5 weight
  • the crushing strength of the fired pellets measured according to the standard ISO 4700 is 2410 N/pellet.
  • the fired pellets are subjected to a swelling test according to standard ISO 4698 and afterwards the crushing strength of the pellets is measured according to the standard ISO 4700.
  • the fired pellets are subjected to a reducibility test according to standard ISO 4695 and afterwards the crushing strength of the pellets is measured according to the standard ISO 4700.
  • the fired pellets are subjected to a desintegration test according to standard ISO 4696 and afterwards the crushing strength of the pellets is measured according to the standard ISO 4700.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Geology (AREA)
  • Environmental & Geological Engineering (AREA)
  • General Life Sciences & Earth Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Inorganic Chemistry (AREA)
  • Manufacture And Refinement Of Metals (AREA)

Abstract

La présente invention concerne l'utilisation d'un composé de magnésium-calcium en tant que liant pour produire des boulettes à fondant de minerai métallique, en particulier des boulettes à fondant de minerai de fer, ledit composé de magnésium-calcium correspondant à la formule générale aCa(OH)2.bMg(OH)2.cMgO.dCaO.eCaCO3.fMgCO3, a, b, c, d, e et f représentant des fractions de poids comprises entre 0 % et 100 % en poids par rapport au poids total dudit composé de magnésium-calcium.
PCT/EP2016/079337 2016-11-30 2016-11-30 Boulettes de minerai métallique WO2018099558A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
PCT/EP2016/079337 WO2018099558A1 (fr) 2016-11-30 2016-11-30 Boulettes de minerai métallique

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/EP2016/079337 WO2018099558A1 (fr) 2016-11-30 2016-11-30 Boulettes de minerai métallique

Publications (1)

Publication Number Publication Date
WO2018099558A1 true WO2018099558A1 (fr) 2018-06-07

Family

ID=57539217

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP2016/079337 WO2018099558A1 (fr) 2016-11-30 2016-11-30 Boulettes de minerai métallique

Country Status (1)

Country Link
WO (1) WO2018099558A1 (fr)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112981096A (zh) * 2021-02-09 2021-06-18 鞍钢股份有限公司 一种含钛镁质熔剂性球团及其制造方法
CN113088686A (zh) * 2021-03-29 2021-07-09 天津市新天钢联合特钢有限公司 一种竖炉不使用润磨机生产的球团矿及其生产方法
CN113136486A (zh) * 2020-06-05 2021-07-20 天津瀚磷国际贸易有限公司 一种加入低镍高铁镍矿的球团生产方法及配方
CN113637844A (zh) * 2021-07-26 2021-11-12 河南锦瀚环保科技有限公司 铁矿粉冷压球团粘结剂及其制备方法
CN113736991A (zh) * 2020-05-27 2021-12-03 上海梅山钢铁股份有限公司 一种高炉炼铁用自熔性冷压复合炉料及其制备方法
CN114908250A (zh) * 2022-05-07 2022-08-16 山东莱钢永锋钢铁有限公司 一种球团用粘结剂及其制备方法、球团矿的制备方法
CN115927843A (zh) * 2022-12-01 2023-04-07 中冶长天国际工程有限责任公司 一种低温固结的复合球团及其制备方法和干燥固结方法
CN116179846A (zh) * 2023-01-29 2023-05-30 中天钢铁集团(南通)有限公司 一种具有高比例赤褐铁矿的球团生产方法

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB990672A (en) * 1963-02-01 1965-04-28 Kennedy Van Saun Mfg & Eng Improvements in method of pelletizing finely divided solid materials
US20040107800A1 (en) * 2002-12-02 2004-06-10 Bansidhar Nayak Process for cold briquetting and pelletisation of ferrous or non-ferrous ores or mineral fines by iron bearing hydraulic mineral binder
FR3008405A1 (fr) * 2013-07-15 2015-01-16 Lhoist Rech & Dev Sa Composition comprenant un ou des composes calco-magnesiens sous forme de compacts

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB990672A (en) * 1963-02-01 1965-04-28 Kennedy Van Saun Mfg & Eng Improvements in method of pelletizing finely divided solid materials
US20040107800A1 (en) * 2002-12-02 2004-06-10 Bansidhar Nayak Process for cold briquetting and pelletisation of ferrous or non-ferrous ores or mineral fines by iron bearing hydraulic mineral binder
FR3008405A1 (fr) * 2013-07-15 2015-01-16 Lhoist Rech & Dev Sa Composition comprenant un ou des composes calco-magnesiens sous forme de compacts

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113736991A (zh) * 2020-05-27 2021-12-03 上海梅山钢铁股份有限公司 一种高炉炼铁用自熔性冷压复合炉料及其制备方法
CN113136486A (zh) * 2020-06-05 2021-07-20 天津瀚磷国际贸易有限公司 一种加入低镍高铁镍矿的球团生产方法及配方
CN112981096A (zh) * 2021-02-09 2021-06-18 鞍钢股份有限公司 一种含钛镁质熔剂性球团及其制造方法
CN113088686A (zh) * 2021-03-29 2021-07-09 天津市新天钢联合特钢有限公司 一种竖炉不使用润磨机生产的球团矿及其生产方法
CN113637844A (zh) * 2021-07-26 2021-11-12 河南锦瀚环保科技有限公司 铁矿粉冷压球团粘结剂及其制备方法
CN114908250A (zh) * 2022-05-07 2022-08-16 山东莱钢永锋钢铁有限公司 一种球团用粘结剂及其制备方法、球团矿的制备方法
CN115927843A (zh) * 2022-12-01 2023-04-07 中冶长天国际工程有限责任公司 一种低温固结的复合球团及其制备方法和干燥固结方法
CN116179846A (zh) * 2023-01-29 2023-05-30 中天钢铁集团(南通)有限公司 一种具有高比例赤褐铁矿的球团生产方法

Similar Documents

Publication Publication Date Title
WO2018099558A1 (fr) Boulettes de minerai métallique
CA2972936C (fr) Procede de dephosphorisation de metal en fusion lors d'un procede de raffinage
JP2009144240A (ja) 焼結鉱製造用成形原料の製造方法
EP2949765B1 (fr) Briquette composite pour la fabrication d'acier et méthode de fabrication dudit acier
US11667989B2 (en) Metallic ore pellets
AU2009273783A1 (en) Process to produce manganese pellets from non-calcinated manganese ore and agglomerate obtained by this process
RU2596730C2 (ru) Способ получения восстановленных железных агломератов
JP2008038181A (ja) 製鉄用含鉄集塵ダスト類の造粒方法
ES2910310T3 (es) Proceso para fabricar un agente de acondicionamiento de escoria para desulfuración de acero
Pal et al. Improving reducibility of iron ore pellets by optimization of physical parameters
Pal et al. Effect of pyroxenite and olivine minerals as source of MgO in hematite pellet on improvement of metallurgical properties
JP2001348623A (ja) 高炉用高品質低ＳｉＯ２焼結鉱の製造方法
CN104313251A (zh) 一种应用高碳钢生产的精炼渣
TWI840473B (zh) 製造用於鋼脫硫之爐渣調整劑的方法、爐渣調整劑及其用途
RU2758701C1 (ru) Шихта для производства ванадиевого чугуна
US20150292055A1 (en) Method for manufacturing reduced iron
RU2625362C2 (ru) Способ получения агломерата восстановленного железа
JP7477064B1 (ja) 還元鉄の製造方法
CN110846497B (zh) 一种含镁熔剂性球团用粘结剂及其制备方法
EP3693478A1 (fr) Procédé d'affinage d'acier et agent de déphosphorisation utilisé dans ledit procédé
KR100280595B1 (ko) 해수 탈탄산 슬러지를 이용한 전기로 로체의 보호방법
KR20000039462A (ko) 제강슬러지를 사용한 철함량이 높은 소결광 제조방법

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 16809316

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 16809316

Country of ref document: EP

Kind code of ref document: A1