SE1300383A1 - Iron and molybdenum-containing briquettes - Google Patents

Abstract

Föreliggande uppfinning avser en process för att framställa järn- och molybdenhaltiga briketter. Den avser även briketter framställda med processen. The present invention relates to a process for producing briquettes containing iron and molybdenum. It also refers to briquettes produced by the process.

Description

1 JARN- OCH MOLYBDENHALTIGA BRIKETTER TEKNISKT OMRADE Foreliggande uppfinning avser en process for att framstdlla jam- och molybdenhaltiga briketter. Den avser dven briketter framstallda med processen. 1 IRON AND MOLYBDE CONTAINING BRIQUETTES TECHNICAL FIELD The present invention relates to a process for producing jam- and molybdenum-containing products briquettes. It refers to briquettes produced with the process.

BAKGRUND Ferromolybden är en jdm—molybden-legering som vanligen har en molybdenhalt av 6080 viktprocent. BACKGROUND Ferromolybdenum is a jdm-molybdenum alloy which usually has a molybdenum content of 6080% by weight.

I de fiesta kommersiella tillampningar framstalls ferromolybden av molybdentrioxid (Mo03) genom en karbotermisk reduktion, en aluminotermisk reduktion eller en kiseltermisk reduktion. Den karbotermiska processen producerar ett ferromolybden med hog kolhalt, medan de tva sistndmnda producerar ett ferromolybden med lag kolhalt. In most commercial applications, the ferro molybdenum is produced from molybdenum trioxide (MoO 3) by a carbothermal reduction, an aluminothermal reduction or a silicon thermal reduction. The carbothermal process produces a high carbon ferromolybdenum, while the latter two produce a low carbon ferromolybdenum.

Ferromolybden med lag kolhalt är vanligare an legeringen med hog kolhalt. Klumpar av ferromolybden som framstallts med dessa metoder har vanligen densiteter runt 9 g/cm3. Att losa upp klumpama i stalsmdltan kan vara svart pa grund av klumpamas hoga smdltpunkt; exempelvis har den kommersiella kvaliteten FeMo70 smdltpunkten 1 950 °C, och eftersom stalsmdltans temperatur är avsevart ldgre paverkas upplosningen av ferromolybdenet huvudsakligen av diffusionsprocesser, vilka forldnger ferromolybdenets upplOsningstid. En annan faktor är den hoga ravarukosmaden i den aluminotermiska reduktionen och de kiseltermiska reduktionerna. Dessutom kan runt 2 % av Mo-innehallet ga forlorat i slaggen i dessa processer. Low carbon ferromolybdenum is more common than high carbon alloy. Lumps of ferro-molybdenum produced by these methods usually have densities around 9 g / cm 3. Dissolving the lumps in the steel melt may be black due to the high melting point of the lumps; for example, the commercial quality FeMo70 has its melting point 1 950 ° C, and since the temperature of the steel medium is considerably lower, the solution is affected of the ferromolybdenum mainly by diffusion processes, which prolong the dissolution time of the ferromolybdenum. Another factor is the high ravarucos food in the aluminothermal reduction and the silicon thermal reductions. Also can around 2% of the Mo content was lost in the slag in these processes.

UPPFINNINGENS SYFTEN Det är ett andamal med uppfinningen att tillhandahalla ett nytt jam- och molybdenhaltigt material som ldmpar sig for molybdentillsats i smdltindustrin, exempelvis stal-, gjuteri- och superlegeringsindustrin, samt en process for att framstalla sadant material pa ett jamforelsevis kostnadseffektivt salt. OBJECTS OF THE INVENTION It is an object of the invention to provide a new jam- and molybdenum-containing material suitable for molybdenum addition in the smelting industry, for example the steel, foundry and superalloy industry, and a process for producing such material on a comparatively cost-effective salt.

Ett ytterligare syfte är att tillhandahalla ett nytt jam- och molybdenhaltigt material som har en jamforelsevis snabb upplosningstid i en stalsmdlta, samt en process for att framstalla sadant material pa ett jdmforelsevis kostnadseffektivt salt. A further object is to provide a new iron- and molybdenum-containing material which has a comparatively rapid dissolution time in a steel medium, and a process for producing such material on a comparatively cost-effective salt.

Ett ytterligare syfte är att tillhandahalla ett nytt jam- och molybdenhaltigt material med lag kol- och hog Mo-halt, samt en process for att framstalla sadant material pa ett jamforelsevis kostnadseffektivt salt. 2 Ett ytterligare syfte är att tillhandahalla ett material som kan vara latt att hantera nar det tillsatts i smaltan, samt en process for att framstalla sadant material pa ett jamforelsevis kostnadseffektivt sat. A further object is to provide a new jam- and molybdenum-containing material with low carbon and high Mo content, as well as a process for producing such material on a comparatively cost-effective salt. 2 A further object is to provide a material which can be easily handled when added to the melt, as well as a process for producing such material in a comparatively cost-effective manner.

SAMMANFATTNING AV UPPFINNINGEN Minst ett av de ovannamnda syftena uppnas atminstone i viss utstrdckning genom en process for att framstalla jam- och molybdenhaltiga briketter innefattande momenten att: a) blanda: ett jamhaltigt pulver, ett molybdenoxidpulver, ett kolhaltigt pulver, en vatska, foretradesvis vatten, valfritt ett bindemedel, och/eller ett smorjmedel ochleller en slaggbildare, b) brikettera for att astadkomma ett flertal rabriketter. SUMMARY OF THE INVENTION At least one of the above objects is achieved at least to some extent by a process for producing jam- and molybdenum-containing briquettes comprising the steps of: a) mixing: a uniform powder, a molybdenum oxide powder, a carbonaceous powder, a liquid, preferably water, optionally a binder, and / or a lubricant and / or a slag former, b) briquettes to produce a plurality of briquettes.

Foretradesvis har rabriketterna en geometrisk densitet i intervallet 1,0-4,0 g/cm3, foretrddesvis 1,2-3,5 g/cm3, mer foredraget 1,2-3,0 g/cm3. Densiteten kan regleras genom att briketteringstrycket varieras. Det är mojligt att framstdlla rabriketter med geometrisk densitet under 2,0 g/cm3, liksom briketter med geometrisk densitet mellan 2,0 och 4,0 g/cm3. De icke-reducerade rabrikettema kan anvandas som substitut for konventionellt tillverkade ferromolybdenlegeringar eller t.o.m. som substitut for molybdenoxid, vid legering av smdltan i industriproduktion. De jam- och/eller molybdenhaltiga rdbrikettema kan framstallas till lagre kostnader an ferromolybden av standardkvalitet. Deras porosa struktur underldttar snabb upplosning i en stalsmdlta. Preferably, the bricks have a geometric density in the range of 1.0-4.0 g / cm 3. preferably 1.2-3.5 g / cm 3, more preferably 1.2-3.0 g / cm 3. The density can be regulated by varying the briquetting pressure. It is possible to produce briquettes with geometric density below 2.0 g / cm3, as well as briquettes with geometric density between 2.0 and 4.0 g / cm 3. The non-reduced bridges can be used as substitutes for conventionally manufactured ferromolybdenum alloys or even as a substitute for molybdenum oxide, in the alloying of smdltan in industrial production. The jam- and / or molybdenum-containing red briquettes can be produced at lower cost than the ferromolybdenum standard quality. Their porous structure facilitates rapid dissolution in a steel melt.

Foretrddesvis innehaller torrsubstanssammansattningen i moment a), i viktprocent: 1-15, foretradesvis 1-10 jarnhaltigt pulver, 5-25, foretradesvis 10-20 kolhaltigt pulver, Valfritt 0,1-smorjmedel och/eller bindemedel och/eller slaggbildare, samt balanserat med minst 50-90 molybdenoxidpulver. Preferably the dry matter composition in step a) contains, in weight percent: 1-15, preferably 1-10 ferrous powder, 5-25, preferably 10-20 carbonaceous powder, Optionally 0,1-lubricants and / or binders and / or slag formers, as well balanced with at least 50-90 molybdenum oxide powder.

Vatska, foretradesvis vatten, tillsdtts foretrddesvis i kvantiteter av 1-10 viktprocent av torrsubstansvikten, foretradesvis 2-5 viktprocent. 3 Foretradesvis anvands varken bindemedel eller slaggbildare. Nar det jarnhaltiga pulvret blandas i vatt tillstand forstarker det briketterna, vilket gör anvandning av bindemedel onodig. Darmed kan kvantiteten fororeningar minskas. Liquid, preferably water, is preferably added in quantities of 1-10% by weight of dry matter weight, preferably 2-5% by weight. 3 Preferably, neither binder nor slag former is used. When the ferrous powder is mixed in an aqueous state, it strengthens the briquettes, which makes the use of binders unnecessary. Thus, the quantity of pollutants can be reduced.

Valfritt omfattar metoden momentet att: c) torka rabriketterna. Optionally, the method comprises the step of: c) dry the briquettes.

Genom att rabriketterna torkas minimeras risken for sprickbildning pa grund av snabb forangning av vatskan nar de varms upp vid hoga temperaturer. By drying the apricots, the risk of cracking is minimized due to rapid evaporation of the liquid when they are heated at high temperatures.

Foretradesvis omfattar det eventuella torkningsmomentet minst ett av fciljande: torkning av rabriketterna till en fukthalt under 5 viktprocent, foretradesvis under 3 viktprocent, torkning av rariketterna vid en temperatur i intervallet 50-250 °C, foretradesvis 80-200 °C, mer foredraget 100-150 °C. Preferably, the possible drying step comprises at least one of the following: drying the briquettes to a moisture content below 5% by weight, preferably less than 3% by weight, drying the ricorettes at a temperature in the range of 50-250 ° C, preferably 80-200 ° C, more preferably 100-150 ° C.

Foretradesvis omfattar metoden momentet att: d) reducera rabriketterna for att astadkomma ett flertal reducerade briketter. Preferably, the method comprises the step of: d) reducing the briquettes to produce a plurality of reduced briquettes.

Foretradesvis omfattar reduktionsmomentet minst ett av fa ljande: - reduktion vid en temperatur i intervallet 800-1 500 °C, foretradesvis 800- 1 350 °C, mer fOredraget 1 000-1 200 °C, reduktion under minst 20 minuter, mer foredraget minst 30 minuter, reduktion i en ugn matad med en inert eller reducerande gas, foretradesvis matad med en svagt reducerande gas, - reduktion vid ett arbetstryck i intervallet 0,1-5 atm, foretradesvis 0,8-2 atm, mer foredraget 1,05-1,2 atm. Preferably, the reduction moment comprises at least one of the following: reduction at a temperature in the range 800-1 500 ° C, preferably 800- 1,350 ° C, more preferred 1,000-1,200 ° C, reduction for at least 20 minutes, more preferably at least 30 minutes, reduction in an oven fed with an inert or reducing gas, preferably fed with a slightly reducing gas, reduction at a working pressure in the range 0.1-5 atm, preferably 0.8-2 atm, more preferred 1.05-1.2 atm.

Foretradesvis omfattar metoden vidare momentet att: e) kyla de reducerade briketterna i en icke-oxiderande atmosfar till en temperatur under 200 °C, mer foredraget under 150 °C, foretradesvis i en inert atmosfar. Preferably, the method further comprises the step of: e) cooling the reduced briquettes in a non-oxidizing atmosphere to a temperature below 200 ° C, more preferably below 150 ° C, preferably in a inert atmosphere.

I en utforingsform utfors brikettering vid ett briketteringstryck i intervallet 801 000 kg/cm2, foretradesvis 100-500 kg/cm2. In one embodiment, briquetting is performed at a briquetting pressure in the range of 801,000 kg / cm 2, preferably 100-500 kg / cm 2.

I en utforingsform utfors brikettering vid ett briketteringstryck i intervallet 1 00010 000 kg/cm2, foretradesvis 2 000-5 000 kg/cm2. 4 De jam- och molybdenhaltiga rabriketterna har en torrsubstanssammansattning av, i viktprocent: 1-15, foretradesvis 1-10 jarnhaltigt pulver, 5-25, foretradesvis 10-20 kolhaltigt pulver, Valfritt 0,1-smorjmedel och/eller bindemedel och/eller slaggbildare, samt balanserat med minst 50-90 molybdenoxidpulver. In one embodiment, briquetting is performed at a briquetting pressure in the range of 1,00010,000 kg / cm 2, preferably 2,000-5,000 kg / cm 2. 4 The jam- and molybdenum-containing briquettes have a dry matter composition of, in% by weight: 1-15, preferably 1-10 ferrous powder, 5-25, preferably 10-20 carbonaceous powder, Optionally 0,1-lubricants and / or binders and / or slag formers, as well balanced with at least 50-90 molybdenum oxide powder.

Torrsubstanssammansattningen avser sammansattningen for ett torkat exemplar, d.v.s. exklusive eventuell fukt som finns i rabrikettema. Fukthalten definieras som det vatten som finns i rabrikettema utover kristallvatten. Fukthalten kan faststallas genom en analys av typen LOD (Loss On Drying, forlust vid torkning) i enlighet med ASTM D2216-10. The dry matter composition refers to the composition of a dried specimen, i.e. excluding any moisture present in the branded themes. The moisture content is defined as the water present in the bricks in addition to crystal water. The moisture content can be determined by an analysis of the type LOD (Loss On Drying, loss on drying) in accordance with ASTM D2216-10.

De reducerade jam- och molybdenhaltiga briketterna har en sammansattning av, i viktprocent: 1-20 Fe, mindre an 10 0, mindre an 10 C, mindre an 15 av andra grundamnen, och balanserat med minst 40 Mo, foretradesvis minst 50 Mo. The reduced jam- and molybdenum-containing briquettes have a composition of, in% by weight: 1-20 Fe, less than 10 0, less than 10 C, less than 15 of the other basic subjects, and balanced with at least 40 Mo, preferably at least 50 Mo.

Foretradesvis har de reducerade briketterna en geometrisk densitet i intervallet 1- 4 g/cm3, foretradesvis 1,2-3,5 g/cm3, mer foredraget 1,2-3,0 g/cm3. Densiteten kan regleras genom att briketteringstrycket for rabrikettema varieras. Det är mojligt att framstalla reducerade briketter med geometrisk densitet under 2,0 g/cm3, och reducerade briketter med geometrisk densitet mellan 2,0 och 4,0 g/cm3. Preferably, the reduced briquettes have a geometric density in the range of 1- 4 g / cm 3, preferably 1.2-3.5 g / cm 3, more preferably 1.2-3.0 g / cm 3. The density can be controlled by varying the briquetting pressure for the briquettes. It is possible to produce reduced briquettes with a geometric density below 2.0 g / cm 3, and reduced briquettes with a geometric density between 2.0 and 4.0 g / cm 3.

Brikettema kan ersatta konventionellt tillverkade ferromolybdenlegeringar, ndr de legeras med molybden vid smaltforfaranden. De jam- och/eller molybdenhaltiga briketterna kan framstallas till lagre kostnader an ferromolybden av standardkvalitet. De jam- och molybdenhaltiga brikettema loses upp snabbare an ferromolybden av standardkvalitet. Beroende pa reduktionstiden, den relativa kvantiteten kol i relation till kvantiteten reducerbara oxider och reduktionstemperaturen kan syrehalten i briketterna minskas delvis eller fullstandigt. Briketterna kan latt transporteras pa ett transportband utan risk att rulla ay. The briquettes can replace conventionally manufactured ferromolybdenum alloys, as they are alloyed with molybdenum in smelting processes. The jam- and / or molybdenum-containing briquettes can be produced at lower costs than standard grade ferro-molybdenum. The jam- and molybdenum-containing briquettes dissolve faster than the ferro-molybdenum standard quality. Depending on the reduction time, the relative quantity of carbon in relation to the quantity of reducible oxides and the reduction temperature can the oxygen content of the briquettes partially or completely reduced. The briquettes can be easily transported on a conveyor belt without the risk of rolling.

KORTA FIGURBESKRIVNINGAR Fig. 1 är en schematisk oversikt over processen att framstalla jam- och molybdenhaltiga briketter enligt uppfinningen. SHORT DESCRIPTION OF FIGURES Fig. 1 is a schematic overview of the process of producing jam- and molybdenum-containing briquettes according to the invention.

BESKRIVNING AV UPPFINNINGEN Uppfinningen kommer nu att beskrivas narmare och med hanvisning till figurerna. DESCRIPTION OF THE INVENTION The invention will now be described in more detail and with reference to the figures.

Fig. 1 är en schematisk oversikt over processen att framstalla jam- och molybdenhaltiga briketter enligt uppfinningen. I blandningsstationen 3 bereds en pulverblandning genom att ett jarnhaltigt pulver, ett kolhaltigt pulver, ett molybdenoxidpulver och vatten blandas. Blandningen i blandningsstationen 3 kan utforas satsvis eller kontinuerligt. Fig. 1 is a schematic overview of the process of producing jam- and molybdenum-containing briquettes according to the invention. In the mixing station 3, a powder mixture is prepared by mixing an iron-containing powder, a carbonaceous powder, a molybdenum oxide powder and water. The mixing in the mixing station 3 can be carried out batchwise or continuously.

Innan molybdenoxidpulvret tillsatts i blandningsstationen 3 kan det malas i tridvalsverket 1. Givetvis kan andra valsverk, kvarnar eller krossar anvandas for att sonderdela molybdenoxiden i mindre partiklar. Dessutom kan det jarnhaltiga pulvret och/eller det kolhaltiga pulvret aven sonderdelas i mindre partiklar genom att det mals och/eller smulas ned och/eller krossas. Before the molybdenum oxide powder is added to the mixing station 3, it can be ground in trid rolling mill 1. Of course, other rolling mills, mills or crushers can be used to probe the molybdenum oxide into smaller particles. In addition, the ferrous powder and / or the carbonaceous powder can also be probed into smaller particles by grinding and / or crumbling and / or crushing.

De malda och/eller nedsmulade och/eller krossade molybdenoxidpartiklarna kan siktas i en sikt 2 for att astadkomma en onskad partikelfOrdelning. Naturligtvis kan siktning aven tillampas for det jarnhaltiga pulvret och/eller det kolhaltiga pulvret. The ground and / or crumbled and / or crushed molybdenum oxide particles can be sieved in a sieve 2 to achieve a desired particle distribution. Of course, sieving can also be applied to the ferrous powder and / or the carbonaceous powder.

I en utforingsform blandas och mals molybdenoxidpulvret och det kolhaltiga pulvret tillsammans, och darefter tillsatts det jarnhaltiga pulvret och blandas med molybdenoxidpulvret och det kolhaltiga pulvret. Emellertid kan valfri kombination av blandningsordning verkstallas. In one embodiment, the molybdenum oxide powder and the carbonaceous powder are mixed and ground together, and then the ferrous powder is added and mixed with the molybdenum oxide powder and the carbonaceous powder. However, any combination of mixing order can be executed.

Jampulver tillsatts i kvantiteter av 1-15 viktprocent, foretradesvis hogst 10 viktprocent av torrsubstansen (d.v.s. exklusive tillsatt vatska). I en foredragen utforingsform 2-5 viktprocent. Jampulver anvands huvudsakligen for aft forstarka briketterna (fungerar exempelvis som bindemedel) men kan aven balansera onskad kvantitet av Fe och Mo i slutprodukten. Molybdenoxidpulver tillsatts i kvantiteter av 50-90 viktprocent av torrsubstansen, foretradesvis 70-90 viktprocent. Yeast powder is added in quantities of 1-15% by weight, preferably at most 10% by weight of the dry matter (i.e. excluding added liquid). In a preferred embodiment 2-5% by weight. Jam powder is mainly used to strengthen the briquettes (works for example as a binder) but can also balance the desired quantity of Fe and Mo in the final product. Molybdenum oxide powder is added in quantities of 50-90% by weight of the dry matter, preferably 70-90% by weight.

Foretradesvis valjs kvantiteten kolhaltigt pulver sa aft en minskning av syrehalten till mindre an 10 viktprocent mojliggors, samtidigt som kolhalten efter full reduktion halls pa mindre an 10 viktprocent, foretradesvis mindre an 5 viktprocent. Foretradesvis balanseras det kolhaltiga pulvret sa att det mesta, foretradesvis allt, av molybdenoxiden kan reduceras till Mo, exempelvis Mo0x, dar x < 0,5. Darigenom blir merparten av 6 aterstaende oxider efter reduktion oxider som är svara att reducera med kol. Exempel pa oxider som är svara att reducera med kol är A1203, Si02, MgO, CaO. Foretradesvis tillsatts 5-25 viktprocent kolhaltigt pulver i blandningen, mer foredraget 10-20 viktprocent. Viktprocenten avser torrsubstanshalten i blandningen (d.v.s. exklusive tillsatt vatska). Preferably, the quantity of carbonaceous powder is chosen so as to reduce the oxygen content to less than 10% by weight, while maintaining the carbon content after full reduction. at less than 10% by weight, preferably less than 5% by weight. Preferably the carbonaceous powder is balanced so that most, preferably all, of the molybdenum oxide can be reduced to Mo, for example Mo0x, where x <0.5. Thereby, the majority of 6 residual oxides after reduction oxides which are responsible for reducing with carbon. Examples of oxides which are responsible for reducing with carbon are Al 2 O 3, SiO 2, MgO, CaO. Preferably 5-25% by weight of carbonaceous powder is added to the mixture, more preferably 10-20% by weight. The percentage by weight refers to the dry matter content of the mixture (i.e. excluding added liquid).

Valfritt kan smOrjmedel och/eller bindemedel och/eller slaggbildare tillsattas under blandningen. De eventuella bindemedlen kan vara organiska eller oorganiska bindemedel. Bindemedlen kan exempelvis vara ett kolhaltigt bindemedel som delvis ersatter det kolhaltiga pulvret. Andra bindemedel kan exempelvis vara bentonit och/eller dextrin och/eller natriumsilikat och/eller kalk. Den eventuella slaggbildaren kan vara kalksten, dolomit och/eller olivin. Den totala kvantiteten eventuella smorjmedel och/eller bindemedel och/eller eventuella slaggbildare kan vara 0,1-10 viktprocent av blandningens torrsubstanshalt, mer foredraget mindre an 5 viktprocent. Den kan vara i intervallet 1-10 viktprocent. Bindemedlen är valfria eftersom fabriketterna genom tillsats av vattnet och jarnet blir tillrackligt starka fcir att reduceras i reduktionsugnen utan allvarlig sprickbildning. Om smorjmedel tillsatts, tillfors det foretradesvis i kvantitetema 0,1-2 procent av blandningens torrsubstanshalt, exempelvis cirka 0,5-1 viktprocent. Smorjmedlet kan exempelvis vara zinkstearat. Emellertid kan andra smorjmedel som am/ands i pulvermetallurgi tillsattas. Optionally, lubricants and / or binders and / or slag formers may be added during mixing. The possible binders can be organic or inorganic binders. The binders may, for example, be a carbonaceous binder which partially replaces the carbonaceous powder. Other binders may be, for example, bentonite and / or dextrin and / or sodium silicate and / or lime. The possible slag former may be limestone, dolomite and / or olivine. The total quantity of any lubricants and / or binders and / or any slag formers may be 0.1-10% by weight of the dry matter content of the mixture, more preferably less than 5% by weight. It can be in the range 1-10% by weight. The binders are optional as the brands through addition of the water and iron becomes sufficiently strong to be reduced in the reduction furnace without severe cracking. If lubricant is added, 0.1-2 percent of the dry matter content of the mixture is preferably added in the quantities, for example about 0.5-1% by weight. The lubricant may, for example, be zinc stearate. However, other lubricants such as those used in powder metallurgy may be added.

Vatska, foretradesvis vatten, tillsatts foretradesvis i kvantiteter av 1-viktprocent av blandningens torrsubstanshalt, foretradesvis 2-5 viktprocent. Liquid, preferably water, is preferably added in quantities of 1% by weight of the dry matter content of the mixture, preferably 2-5% by weight.

Fran blandningsstationen 3 overfOrs den beredda pulverblandningen till en briketteringsmaskin 4. I briketteringsmaskinen 4 briketteras pulverblandningen for att astadkomma ett flertal rabriketter. From the mixing station 3, the prepared powder mixture is transferred to a briquetting machine 4. In the briquetting machine 4, the powder mixture is briquetted to accomplish a number of bridges.

I en utforingsform briketteras pulverblandningen vid ett jamforelsevis Mgt briketteringstryck, foretradesvis med anvandning av ett briketteringstryck i intervallet 80-1 000 kg/cm2, mer foredraget 100-500 kg/cm2. Det laga briketteringstrycket har visat sig forbattra kvaliteten hos de framstallda rabrikettema. In one embodiment, the powder mixture is briquetted at a comparatively Mgt briquetting pressure, preferably using a briquetting pressure in the range 80-1 000 kg / cm2, more preferably 100-500 kg / cm2. The low briquetting pressure has proved to improve the quality of the manufactured briquettes.

I en annan utforingsform arbetar briketteringsmaskinen vid hogre tryck, exempelvis 1 000-10 000 kg/cm2. Hogre tryck kan anvandas for att Oka rabriketternas geometriska densitet. 7 Foretradesvis är briketteringsmaskinen 4 en valspress. Emellertid kan andra typer av briketteringsmaskiner anvandas. In another embodiment, the briquetting machine operates at higher pressures, for example 1,000-10,000 kg / cm2. Higher pressures can be used to increase the geometric density of the bricks. 7 Preferably, the briquetting machine 4 is a roller press. However, other types of briquetting machines can be used.

De rabriketter som framstalls av pulverblandningen reduceras foretradesvis i en 5 reduktionsugn 6. Alternativt kan de icke-reducerade rabriketterna anvandas som legeringstillsats vid jam- och stalframstallning. The briquettes produced from the powder mixture are preferably reduced in a reduction furnace 6. Alternatively, the non-reduced briquettes can be used as an alloy additive in jam and steel production.

Valfritt torkas rabriketterna innan de overfors till reduktionsugnen 6. Manga olika typer av industritorkar kan anvandas. Brikettema kan awn torkas utan aktiv uppvarmning, exempelvis i omgivningstemperatur. I en tork kan anga avldgsnas med en gasanga eller med vakuum. Rabriketterna kan torkas tills onskad fukthalt har nâtts. Rabriketterna kan torkas till en fukthalt mindre an 10 viktprocent, mer foredraget mindre an 5 viktprocent, mest foredraget mindre an 3 viktprocent. Rabrikettema kan torkas vid en temperatur i intervallet 50-250 °C, mer foredraget 80-200 °C, mest foredraget 100-150 °C. For forbattrad processekonomi är torktiden fOretradesvis i intervallet 10-120 minuter, mer foredraget 20-60 minuter. Men langre torktider är givetvis tankbara. Fukthalten definieras som det vatten som finns i rabriketterna utover kristallvatten. Fukthalten kan faststallas genom en analys av typen LOD (Loss On Drying, fOrlust vid torkning) i enlighet med ASTM D2216-10. Optionally, the briquettes are dried before being transferred to the reduction furnace 6. Many different types of industrial dryers can be used. The briquettes can be awn dried without active heating, for example at ambient temperature. In a dryer the steam can be removed with a gas steam or with a vacuum. The briquettes can be dried until the desired moisture content has been reached. The briquettes can be dried to a moisture content of less than 10% by weight, more preferably less than 5% by weight, most preferably less than 3% by weight. The briquettes can be dried at a temperature in the range 50-250 ° C, more preferably 80-200 ° C, most preferably 100-150 ° C. For improved process economy, the drying time is preferably in the range of 10-120 minutes, more lecture 20-60 minutes. But longer drying times are of course conceivable. The moisture content is defined as the water present in the briquettes in addition to crystal water. The moisture content can be determined by an analysis of the LOD (Loss On Drying) type in accordance with ASTM D2216-10.

Rabrikettema reduceras foretradesvis i en reduktionsugn 6. Reduktionsugnen är foretradesvis en genommatningsugn men kan aven vara en satsugn. Genommatningsugnen 6 har ett inlopp 7 och ett utlopp 8, och brikettema transporteras under reduktionen fran inloppet 7 till utloppet 8. I en fOredragen utfOringsform anvands en ugn med transportband. The briquettes are preferably reduced in a reduction furnace 6. The reduction furnace is preferably a feed furnace but can also be a batch furnace. The feed-through furnace 6 has an inlet 7 and an outlet 8, and the briquettes are transported during the reduction from the inlet 7 to the outlet 8. In a preferred embodiment, an oven with conveyor belt.

Rabriketterna reduceras vid en temperatur i intervallet 800-1 500 °C, foretradesvis 8001 350 °C, mer foredraget 1 000-1 200 °C, foretradesvis i minst 20 minuter, mer foredraget minst 30 minuter. Genom overvakning av bildandet av CO/CO2 kan det faststallas nar reduktionsprocessen är avslutad. Foretradesvis är reduktionstiden hogst 10 timmar, foretradesvis hogs( 2 timmar, mer foredraget hogst 1 timme. Beroende pa reduktionstiden, reduktionstemperaturen och forhallandet mellan kol och reducerbara oxider i briketterna kan briketternas reducerbara oxider reduceras delvis eller fullstandigt. The briquettes are reduced at a temperature in the range 800-1 500 ° C, preferably 8001 350 ° C, more preferably 1000-1 200 ° C, preferably for at least 20 minutes, more preferably at least 30 minutes. By monitoring the formation of CO / CO2, it can be determined when the reduction process is completed. Preferably, the reduction time is maximum 10 hours, preferably increased (2 hours, more preferably increased to 1 hour. Depending on the reduction time, the reduction temperature and the ratio of carbon to reducible oxides in the briquettes, the reducible oxides of the briquettes can be partially or completely reduced.

Valfritt vdrmebehandlas rabriketterna vid en lagre temperatur fore reduktion. Optionally, the briquettes are heat-treated at a lower temperature before reduction.

Foretradesvis varmebehandlas rabriketterna vid en temperatur i intervallet 200-800 °C, mer foredraget 400-700 °C. Foretradesvis sker den eventuella vdrmebehandlingen vid 8 lagre temperatur fran minuter till mindre an 2 timmar, foretradesvis mindre an 1 timme. Genom varmebehandling vid lagre temperaturer kan det eventuella smorjmedlet brannas bort pa ett kontrollerat salt. Dessutom kan molybdentrioxid reduceras till molybdendioxid. Detta kan anvandas som ett forreduktionsmoment fore den reduktion som beskrivs i foregaende stycke eller vid framstallning av delvis reducerade briketter. Preferably the briquettes are heat treated at a temperature in the range 200-800 ° C, more preferably 400-700 ° C. Preferably, the possible heat treatment takes place at 8 lower temperature from minutes to less than 2 hours, preferably less than 1 hour. By heat treatment at lower temperatures, any lubricant can be burned off on a controlled salt. In addition, molybdenum trioxide can be reduced to molybdenum dioxide. This can be used as a pre-reduction moment before the reduction as described in the preceding paragraph or in the manufacture of partially reduced briquettes.

Den eventuella varmebehandlingen vid 200-800 °C kan utforas i samma ugn som reduktionen. Den eventuella varmebehandlingen och den eventuella torkningen kan ocksa kombineras. The possible heat treatment at 200-800 ° C can be carried out in the same oven as the reduction. The possible heat treatment and the possible drying can also be combined.

Ovantat har det payisats att briketter kan reduceras vid hOga temperaturer utan markbara sublimeringsforluster av Mo03. Foljaktligen resulterar den patentsokta processen i en forenklad process som medfor forbattrat utbyte och hogre Mo-halt i slutprodukten. Det finns alltsa inget behov av att utfOra en forreduktion med avseende pa sublimeringsforluster av Mo03. Unexpectedly, it has been paid that briquettes can be reduced at high temperatures without markings sublimation losses of Mo03. Consequently, the patent-pending process results in a simplified process that results in improved yields and higher Mo content in the final product. Thus, there is no need to perform a pre-reduction with respect to sublimation losses of Mo03.

Under reduktionen kan CO och CO2 bildas genom reaktioner med kolkallan och de reducerbara oxiderna i briketterna. Dessutom kan aterstaende fukt forangas. Reduktionstiden kan optimeras genom att bildandet av CO och CO2 mats, i synnerhet CO eftersom CO2 bildas huvudsakligen under de fOrsta minuterna av reduktionen varefter CO-bildandet dominerar tills kolkallan är forbrukad eller alla reducerbara oxider har reducerats. During the reduction, CO and CO2 can be formed by reactions with the carbon dioxide and the reducible oxides in the briquettes. In addition, residual moisture can evaporate. The reduction time can be optimized by feeding the formation of CO and CO2, in particular CO because CO2 is formed mainly during the first minutes of the reduction after which the CO formation dominates until the carbon dioxide is consumed or all reducible oxides have been reduced.

Reduktionsreaktionerna är endoterma och kraver varme. Foretradesvis alstras varme av varmeaggregat som inte paverkar atmosfaren inuti ugnen, mer foredraget alstras varmen genom elektrisk uppvarmning. The reduction reactions are endothermic and require heat. Preferably, heat is generated by heaters which do not affect the atmosphere inside the oven, more preferably the heat is generated by electric heating.

Atmosfdren inuti ugnen 6 regleras foretradesvis genom att en inert eller en reducerande gas, foretradesvis en svagt reducerande gas, matas in i en ande av ugnen, och att gaser (exempelvis reaktionsgaser (exempelvis CO, CO2, och H20) och den inmatade gasen) evakueras i den motsatta anden, mer foredraget genom att den inerta eller reducerande gasen matas in motstroms vid en utloppssida 8 av ugnen 6, och att gaser evakueras vid en inloppssida 7 av ugnen 6. Del betyder att den inerta eller reducerande gasen foretradesvis matas motstroms. Den inerta gasen eller en reducerande gas kan exempelvis vara argon, N2, H2 eller valfri blandning av H2/N2 (exempelvis i forhallandet 5:95 med avseende volym). The atmosphere inside the furnace 6 is preferably controlled by an inert or a reducing gas, preferably a slightly reducing gas, is fed into one spirit of the furnace, and that gases (e.g. reaction gases (e.g. CO, CO 2, and H 2 O) and the feed gas) are evacuated in the opposite spirit, more preferably by feeding the inert or reducing gas countercurrently at an outlet side 8 of the furnace 6, and gases being evacuated at an inlet side 7 of the furnace 6. Part means the inert or reducing gas preferably fed countercurrently. The inert gas or a reducing gas can for example be argon, N2, H2 or any mixture of H2 / N2 (for example in the ratio 5:95 by volume).

Foretradesvis arbetar ugnen vid ett tryck i intervallet 0,1-5 atm, foretradesvis 0,8-2 atm, mer foredraget vid ett tryck i intervallet 1,0-1,5 atm, mest foredraget 1,05-1,2 atm. 9 Vid reduktionsugnens utlopp 8 overfors briketterna till en kylsektion 9, for att briketterna ska kylas i en icke-oxiderande atmosfar (exempelvis reducerande eller inert) till en temperatur under 200 °C for att undvika ateroxidation av briketterna, mer foredraget under 150 °C i en inert atmosfar. Atmosfaren kan exempelvis vara argon, N2, H2 eller valfri blandning av H2/N2 (exempelvis i forhallandet 5:95 med avseende pa volym). Aven andra atmosfarer kan anvandas. Om det är onskvart att ha mycket laga nivaer av kvave i briketterna, kan briketterna kylas i en kvavefri atmosfar sasom exempelvis en argongasatmosfar. Preferably the furnace operates at a pressure in the range 0.1-5 atm, preferably 0.8-2 atm, more preferably at one pressure in the range 1.0-1.5 atm, most preferably 1.05-1.2 atm. 9 At the outlet 8 of the reduction furnace, the briquettes are transferred to a cooling section 9, so that the briquettes are cooled in a non-oxidizing atmosphere (for example reducing or inert) to a temperature below 200 ° C to avoid atheroxidation of the briquettes, more preferably below 150 ° C in a inert atmosphere. The atmosphere may be, for example, argon, N2, H2 or any mixture of H2 / N2 (for example in the ratio 5:95 with respect to pa volume). Other atmospheres can also be used. If it is undesirable to have very low levels of nitrogen in the briquettes, the briquettes can be cooled in a nitrogen-free atmosphere such as an argon gas atmosphere.

Molybdenoxidpulver Molybdenoxidpulvret är foretradesvis ett molybdentrioxidpulver. Pulvret kan awn vara ett molybdendioxidpulver eller en blandning av molybdentrioxidpulver och molybdendioxidpulver. Molybdenum oxide powder The molybdenum oxide powder is preferably a molybdenum trioxide powder. The powder may be a molybdenum dioxide powder or a mixture of molybdenum trioxide powder and molybdenum dioxide powder.

Molybdenpulvret bor innehalla 50-80 Mo, varvid ovriga grundamnen är syre och fororeningar. Ju renare kvaliteten av molybdenoxid är, desto renare kan de jam- och molybdenhaltiga briketterna goras. Emellertid är renare kvaliteter av Mo03 a andra sidan dyrare. The molybdenum powder should contain 50-80 Mo, with the other basic elements being oxygen and impurities. The purer the quality of molybdenum oxide, the cleaner the jam- and molybdenum-containing briquettes can be made. However, cleaner grades of Mo03 on the other hand are more expensive.

I en foredragen utforingsform anvands Mo03 av teknisk kvalitet. Sadana pulver är mindre kostsamma an renare kvaliteter av Mo03 och kan innehalla oxider som är svara att reducera vid reduktion i fast tillstand med kol. Exempel pa sadana oxider är A1203, Si02 och MgO. Lyckligtvis kan dessa oxider enkelt avldgsnas till slaggfasen vid legering i stalsmaltor och de kan ddrfOr tillatas i produkten. In a preferred embodiment, Mo03 of technical quality is used. Such powders are less expensive than purer grades of MoO 3 and may contain oxides which are likely to reduce on solid state reduction with carbon. Examples of such oxides are Al 2 O 3, SiO 2 and MgO. Fortunately, these oxides can be easily degraded to the slag phase by alloying in steel malts and they can therefore be allowed in the product.

Foretradesvis passerar minst 90 viktprocent av partiklarna i molybdenoxidpulvret genom en testsikt med nominell halstorlek av 300 nm, och minst 50 viktprocent av partiklama i molybdenoxidpulvret passerar genom en testsikt med nominell halstorlek av 125 nm. Mer foredraget passerar minst 90 viktprocent av partiklarna i molybdenoxidpulvret genom en testsikt med nominell halstorlek av 125 tm, och minst viktprocent av partiklarna i molybdenoxidpulvret passerar genom en testsikt med nominell halstorlek av 45 iLtm. De nominella halstorlekarna i foreliggande patentansokan är i enlighet med ISO 565:1990, vilken standard harmed inforlivas genom hanvisning. Preferably, at least 90% by weight of the particles in the molybdenum oxide powder pass through a 300 nm nominal neck sieve test screen, and at least 50% by weight of the molybdenum oxide powder particles pass through a 125 nm nominal neck size test. More preferably, at least 90% by weight of the particles in the molybdenum oxide powder passes through a test sieve with a nominal neck size of 125 .mu.m, and at least a percentage by weight of the particles in the molybdenum oxide powder pass through a test sieve with a nominal neck size of 45 .mu.m. The nominal neck sizes in the present patent application are in accordance with ISO 565: 1990, which standard is hereby incorporated by reference.

I en utforingsform passerar minst 90 viktprocent, mer foredraget minst 99 viktprocent, av partiklarna i molybdenoxidpulvret genom en testsikt med nominell halstorlek av 250 um, mer foredraget 125 gm, mest foredraget 45 gm. In one embodiment at least 90% by weight, more preferably at least 99% by weight, of the particles in the molybdenum oxide powder through a test sieve with a nominal neck size of 250 μm, more preferably 125 μm, most preferably 45 μm.

Jarnhaltigt pulver Det jarnhaltiga pulvret är foretradesvis eft jarnpulver innehallande minst 80 viktprocent Fe, foretradesvis minst 90 viktprocent Fe, mer foredraget minst 95 viktprocent Fe, mest foredraget minst 99 viktprocent Fe. Jarnpulvret kan vara ett jarnsvamppulver och/eller ett vattenatomiserat jarnpulver och/eller ett gasatomiserat jarnpulver och/eller ett jarnfilterstoft och/eller ett jarnslampulver. Exempelvis är filterstoftet X-RFS40 fran Hogands AB, Sverige ett lampligt pulver. Ferrous powder The iron-containing powder is preferably after iron powder containing at least 80% by weight of Fe, preferably at least 90% by weight of Fe, more preferably at least 95% by weight of Fe, most preferably at least 99% by weight of Fe. The iron powder may be an iron fungus powder and / or a water atomized iron powder and / or a gas atomized iron powder and / or a iron filter dust and / or an iron sludge powder. For example, the filter dust X-RFS40 from Hogands AB, Sweden is a suitable powder.

Jampulvret kan delvis eller fullstandigt ersattas av ett jarnoxidpulver, exempelvis men inte begransat till: pulver bestaende av ett eller flera fran gruppen FeO, Fe203, Fe304, Fe0(OH), (Fe203*H20). Jarnoxidpulvret kan exempelvis vara frasspan. Foretradesvis innehaller det jarnhaltiga pulvret minst 50 viktprocent metalliskt jam, mer foredraget minst 80 viktprocent metalliskt Fe, mest foredraget minst 90 viktprocent metalliskt Fe. The jam powder can be partially or completely replaced by an iron oxide powder, for example but not limited to: powder consisting of one or more of the group FeO, Fe203, Fe304, Fe0 (OH), (Fe2 O3 * H2 O). The iron oxide powder can, for example, be crisp. Preferably the ferrous powder contains at least 50% by weight of metallic jam, more preferably at least 80% by weight of metallic Fe, most preferably at least 90% by weight of metallic Fe.

FOretradesvis passerar minst 90 viktprocent av partiklarna i det jarnhaltiga pulvret genom en testsikt med nominell halstorlek av 125 tm, och minst 50 viktprocent av partiklarna i det jarnhaltiga pulvret passerar genom en testsikt med nominell halstorlek av 45 lam. Preferably, at least 90% by weight of the particles in the ferrous powder pass through a test sieve with a nominal throat size of 125 tm, and at least 50% by weight of the particles in the ferrous powder pass through a test sieve with a nominal throat size of 45 lam.

I en utforingsform passerar minst 90 viktprocent, mer foredraget minst 99 viktprocent, av partiklarna i det jarnhaltiga pulvret genom en testsikt med nominell halstorlek av 125 gm, mer foredraget 45 lam. I ett exempel passerar minst 90 viktprocent, mer foredraget minst 99 viktprocent, av partiklarna i det jarnhaltiga pulvret genom en testsikt med nominell halstorlek av 20 um. In one embodiment, at least 90% by weight, more preferably at least 99% by weight, of the particles in the iron-containing powder pass through a test screen with a nominal neck size of 125 gm, more preferably 45 lam. In one example, at least 90% by weight, more preferably at least 99% by weight, of the particles in the ferrous powder pass through a test sieve with a nominal neck size of 20 μm.

Kolhaltigt pulver Det kolhaltiga pulvret är foretradesvis valt fran gruppen av: subbituminosa kolsorter, bituminosa kolsorter, brunkol, antracit, koks, petroleumkoks och biokol sasom trakol, eller kolhaltiga pulver som bearbetats utifran dessa resurser. Det kolhaltiga pulvret kan exempelvis vara sot, kimrok, aktivt kol. Det kolhaltiga pulvret kan aven vara en blandning av olika kolhaltiga pulver. Carbonated powder The carbonaceous powder is preferably selected from the group of: subbituminosa carbons, bituminosa carbons, lignite, anthracite, coke, petroleum coke and biochar such as tracol, or carbonaceous powders processed from these resources. The carbonaceous powder can for example be soot, carbon black, activated carbon. The carbonaceous powder may also be one mixture of different carbonaceous powders.

For valet av kolpulver tas foretradesvis hansyn till kolets reaktivitet, eftersom bade produktiviteten och utbytet av Mo beror pa denna faktor. Hog reaktivitet är onskvard. I synnerhet är det onskvart all ha ett kolhaltigt pulver som är reaktivt vid lagre temperaturer (foretradesvis < 700 °C ). Exempelvis är tyskt brunkol (lignit) vanligen reaktivt vid lagre temperaturer an petroleumkoks, och är darfor lampligt eftersom det 11 har jamforelsevis hog reaktivitet vid laga temperaturer. Aven trakol samt bituminosa och subbituminosa kolsorter kan uppvisa jamforelsevis hog reaktivitet. Sarskilt lampliga exempel är sot, kimrOk och aktivt kol. For the choice of carbon powder, consideration is preferably given to the reactivity of the carbon, since both the productivity and the yield of Mo depend on this factor. High reactivity is undesirable. IN in particular, it is desirable to have a carbonaceous powder which is reactive at bearings temperatures (preferably <700 ° C). For example, German lignite (lignite) is usually reactive at lower temperatures than petroleum coke, and is therefore suitable because it 11 has comparatively high reactivity at low temperatures. Trachol as well as bituminosa and subbituminosa carbon species can show comparatively high reactivity. Particularly suitable examples are soot, carbon black and activated carbon.

Kvantiteten kolhaltigt pulver bestams foretradesvis genom att kvantiteten oxider i molybdenoxidpulvret, och valfritt det jarnhaltiga pulvret, analyseras. Foretradesvis bestams kvantiteten reducerbara oxider. Syrehalten kan exempelvis analyseras med en LECOO TC400. Dessutom tas foretradesvis aven hansyn till den maximalt tillatna kolhalten i briketterna. FOretradesvis valjs kvantiteten sâ att den stOkiometriskt motsvarar eller i nagon man overstiger kvantiteten reducerbara metalloxider i molybdenoxidpulvret och det jarnhaltiga pulvret. Emellertid kan kvantiteten kol aven vara understokiometrisk. The quantity of carbonaceous powder is preferably determined by the quantity of oxides in the molybdenum oxide powder, and optionally the ferrous powder, are analyzed. Preferably, the quantity of reducible oxides is determined. The oxygen content can, for example, be analyzed with a LECOO TC400. In addition, the maximum permissible carbon content of the briquettes is also taken into account. Preferably, the quantity is selected so that it is stoichiometric corresponds to or in any case exceeds the quantity of reducible metal oxides in the molybdenum oxide powder and the ferrous powder. However, the quantity of carbon can also be understochiometric.

Kvantiteten kolhaltigt pulver kan optimeras genom att kol- och syrenivaerna mats i de reducerade briketterna (exempelvis genom att rabriketter reduceras i en laboratorieugn samt att kol- och syrenivaerna mats). Baserat pa matningarna kan kvantiteten kolhaltigt pulver optimeras for att uppna onskade nivaer av kol och syre i de framstallda briketterna. Vissa oxider som kan finnas i molybdenoxidpulvret är svara att reducera med kol. Alla oxider med hogre affinitet for syre vid reduktionens maxtemperatur kommer att kvarsta som oxider i den fardiga produkten och forbrukar darfor inte kol i reduktionsprocessen. Sadana oxider kan exempelvis vara oxider av Si, Ca, Al och Mg och kan exempelvis inga om mera orena kvaliteter av molybdentrioxid am/ands, exempelvis teknisk molybdentrioxid. Emellertid kan dessa oxider hanteras inom manga anyandningsomraden av stalmetallurgi, exempelvis genom att de avliigsnas i stalsmaltans slagg, och de kan dad& tillatas i briketterna. Om mindre kvantiteter av dessa oxider och grundamnen onskas, kan renare kvaliteter av molybdentrioxid anvandas, exempelvis kvaliteter som innehaller mindre eller inga kvantiteter av dessa oxider. The quantity of carbonaceous powder can be optimized by feeding the carbon and oxygen levels into them reduced briquettes (for example by reducing briquettes in a laboratory oven and that the carbon and oxygen levels are fed). Based on the feeds, the quantity of carbonaceous powder can be optimized to achieve the desired levels of carbon and oxygen in the briquettes produced. Some oxides that may be present in the molybdenum oxide powder are responsible for reducing with carbon. All oxides with higher affinity for oxygen at the maximum temperature of the reduction will remain as oxides in the finished product and therefore do not consume carbon in the reduction process. Such oxides may, for example, be oxides of Si, Ca, Al and Mg and may, for example, have no more impure qualities of molybdenum trioxide, for example technical molybdenum trioxide. However, these oxides can be handled in many areas of steel metallurgy, for example by removing them in steel malt slag, and they can be dad & allowed in the briquettes. About smaller quantities of these oxides and the elements are desired, purer grades of molybdenum trioxide can be used, for example grades containing less or no quantities of these oxides.

Genom att kvantiteten kolhaltigt pulver regleras och anpassas efter kvantiteten reducerbara oxider i rbriketterna kan jam- och molybdenhaltiga briketter framstallas som har en kolhalt (efter reduktion) mindre an 10 viktprocent, foretradesvis mindre an 5 viktprocent, mer foredraget mindre an 1 viktprocent, mest foredraget mindre an 0,5 viktprocent. 12 Emellertid är det aven mojligt att tillhandahalla briketter med avsiktligt hog kolhalt efter reduktion, exempelvis 1-5 viktprocent C. Sa.dana briketter kan anvandas vid legering av stal med hog kolhalt. By regulating the quantity of carbonaceous powder and adapting it to the quantity Reducible oxides in the briquettes, jam and molybdenum-containing briquettes can be prepared which have a carbon content (after reduction) of less than 10% by weight, preferably less than 5% by weight, more preferably less than 1% by weight, most preferably less than 0.5% by weight. 12 However, it is also possible to provide briquettes with intentionally high carbon content after reduction, for example 1-5% by weight C. Such briquettes can be used in alloying high carbon steels.

Foretradesvis passerar minst 90 viktprocent, mer foredraget minst 99 viktprocent, av partiklama i det kolhaltiga pulvret genom en testsikt med nominell halstorlek av 125 lam, och minst 50 viktprocent av partiklama i det kolhaltiga pulvret passerar genom en testsikt med nominell halstorlek av 45 lam. Preferably at least 90% by weight, more preferably at least 99% by weight, passes by the particles in the carbonaceous powder through a test sieve with a nominal neck size of 125 lam, and at least 50% by weight of the particles in the carbonaceous powder pass through a test sieve with a nominal neck size of 45 lam.

I en utforingsform passerar minst 90 viktprocent, mer foredraget minst 99 viktprocent, av partiklarna i det kolhaltiga pulvret genom en testsikt med nominell halstorlek av och minst 50 viktprocent av partiklarna i det kolhaltiga pulvret passerar genom en testsikt med nominell halstorlek av 20 Rm. I ett exempel passerar minst 90 viktprocent, mer foredraget minst 99 viktprocent, av partiklarna i det kolhaltiga pulvret genom en testsikt med nominell halstorlek av 20 pm. In one embodiment at least 90% by weight, more preferably at least 99% by weight, of the particles in the carbonaceous powder through a test sieve with a nominal neck size of and at least 50% by weight of the particles in the carbonaceous powder pass through a test screen with a nominal neck size of 20 Rm. In one example, at least 90% by weight, more preferably at least 99% by weight, of the particles in the carbonaceous powder pass through a test sieve with a nominal neck size of 20 μm.

Jam- och molybdenhaltiga rabriketter Jam- och molybdenhaltiga fabriketter med en torrsubstanssammansattning av, i viktprocent: 1-15, foretradesvis 1-10 jamhaltigt pulver, 5-25, foretradesvis 10-20 kolhaltigt pulver, Valfritt 0,1-smorjmedel och/eller bindemedel och/eller slaggbildare, och balanserat med minst 50-90 molybdenoxidpulver. Jam and molybdenum-containing briquettes Jam and molybdenum-containing plants with a dry matter composition of, by weight: 1-15, preferably 1-10 jam-containing powder, 5-25, preferably 10-20 carbonaceous powder, Optionally 0,1 lubricants and / or binders and / or slag formers, and balanced with at least 50-90 molybdenum oxide powder.

I en utforingsform bestar thbriketternas torrsubstanssammansattning av, i viktprocent: 1-15, foretradesvis 1-10 jarnhaltigt pulver, 5-25, foretradesvis 10-20 kolhaltigt pulver, balanserat med 50-90 molybdenoxidpulver. In one embodiment, the dry matter composition of the briquettes consists of, in weight percent: 1-15, preferably 1-10 ferrous powder, 5-25, preferably 10-20 carbonaceous powder, balanced with 50-90 molybdenum oxide powder.

Vad avser grundamnen har de jam- och molybdenhaltiga rabrikettema foretradesvis en torrsubstanssammansattning av, i viktprocent: 1-15 Fe, 15-40 0,5-25 C, mindre an 15 av andra grundamnen utover 0, C, Mo och Fe, och balansen är minst 30 Mo. As for the elements, the jam- and molybdenum-containing briquettes preferably have a dry matter composition of, in% by weight: 1-15 Fe, 15-40 0.5-25 C, less than 15 of the other elements in addition to 0, C, Mo and Fe, and the balance is at least 30 Mo.

Jam utgor foretradesvis i intervallet 1,5-10 viktprocent. Jam is preferably in the range of 1.5-10% by weight.

Kol utgor foretradesvis 7-20 viktprocent. Carbon preferably constitutes 7-20% by weight.

Syre utgor fOretradesvis 15-30 viktprocent. Oxygen is preferably 15-30% by weight.

Molybden utgor foretradesvis 40-65 viktprocent. Molybdenum preferably constitutes 40-65% by weight.

Andra grundamnen utgor foretradesvis minst 1 viktprocent och mindre an 13 viktprocent, mer foredraget minst 2 viktprocent och mindre an 7 viktprocent. Other elements preferably contain at least 1% by weight and less 13 weight percent, more preferably at least 2 weight percent and less than 7 weight percent.

I efterffiljande reduktionsmoment kommer den relativa kvantiteten jam och molybden att Oka i brikettema allteftersom reduktionen fortskrider. Detsamma galler givetvis for 5 de &riga grundamnen som aterstar. In the subsequent reduction step, the relative quantity of jam and molybdenum will increase in the briquettes as the reduction progresses. The same applies, of course, to the 5 basic elements that remain.

Rabriketterna kan vara kostnadseffektiva substitut ffir Mo03-pulver eller standard-FeMo vid legering i smaltforfaranden, med hansyn till pris och/eller utbyte av Mo-tillsatsen i smaltan. Normalt skulle sadan tillsats kunna goras exempelvis i elektrisk ljusbagsugn och exempelvis utgora en Mo-tillsats i rostfritt stal, verktygsstal eller snabbstal. The briquettes can be cost-effective substitutes for MoO3 powder or standard FeMo in alloying in smelting processes, with regard to price and / or replacement of the Mo additive in the smelter. Normally, such an additive could be made, for example, in an electric candle baking oven and, for example, constitute a Mo additive in stainless steel, tool steel or high-speed steel.

Rabriketterna har en geometrisk densitet i intervallet 1,0-4,0 g/cm3, foretradesvis 1,23,5 g/cm3, mer foredraget 1,2-3,0 g/cm3. Densiteten kan okas genom att briketteringstrycket okas. En lagre geometrisk densitet resulterar i hogre porositet, vilket anses ge en kortare upplosningstid for brikettema. Den geometriska (envelopp-) densiteten kan matas i enlighet med ASTM 962-08. The briquettes have a geometric density in the range 1.0-4.0 g / cm 3, preferably 1.23.5 g / cm 3, more preferably 1.2-3.0 g / cm 3. The density can be increased by increasing the briquetting pressure. A lower geometric density results in higher porosity, which is considered to give a shorter dissolution time for the briquettes. The geometric (envelope) the density can be fed in accordance with ASTM 962-08.

Reducerade jam- och molybdenhaltiga briketter De reducerade jam- och molybdenhaltiga briketterna har en sammansattning av, i viktprocent: 1-20 Fe, mindre an 10 0, mindre an 10 C, mindre an 15 av andra grundamnen uffiver 0, C, Mo och Fe, och balanserat med minst 40 Mo, foretradesvis minst 50 Mo. Reduced jam and molybdenum-containing briquettes The reduced jams and molybdenum-containing briquettes have a composition of, in weight percent: 1-20 Fe, less than 10 0, less than 10 C, less than 15 of other the elements uffiver 0, C, Mo and Fe, and balanced with at least 40 Mo, preferably at least 50 Mo.

Foretradesvis är halten 0 mindre an 10 viktprocent, mer foredraget mindre an 8 viktprocent, annu mer foredraget mindre an 6 viktprocent, mest foredraget mindre an 4 viktprocent, och foretradesvis kommer endast en minoritet av syreinnehallet fran molybdenoxid som inte har reducerats, d.v.s. en brikett som innehaller Mo0x, dar x < 0,5. Foretradesvis reduceras vasentligen all molybdenoxid till Mo, d.v.s. dar x är runt 0. Har kommer aterstaende syreinnehall huvudsakligen fran oxider i molybdenoxidpulvret och det jarnhaltiga pulvret som ãr svara att reducera, exempelvis oxider av Si, Ca, Al och Mg. Med anvandning av renare kvaliteter av molybdenoxidpulvret, det jamhaltiga pulvret och det kolhaltiga pulvret kan brikettemas syrehalt, om sa onskas, goras Egre an 2 viktprocent. Emellertid, eftersom manga av dessa oxider som är svara att reducera kan hanteras inom stalsmaltmetallurgi (exempelvis genom aft de avlagsnas i slaggfasen), kan de tillatas i den jam- och molybdenhaltiga briketten. Den nedre gransen for syre kan vara cirka 0 viktprocent, men normalt utgor syret minst 1 viktprocent, oftare minst 2 viktprocent. 14 Molybdenhalten i briketterna kan regleras genom att de relativa proportionerna av molybdenoxidpulvret varieras i relation till det jarnhaltiga pulvret. For vasentligen fullstandigt reducerade briketter (d.v.s. briketter innehallande MoOx dar x < 0,5) regleras foretradesvis halten molybden till intervallet 60-95 viktprocent. Mer foredraget är halten Mo i intervallet 65-95 viktprocent, mest foredraget är halten Mo i intervallet 70-95 viktprocent. Overraskande nog har en mycket hog upplOsningstakt funnits for reducerade briketter med en molybdenhalt av 80-95 viktprocent. Detta resultat beror pa den mycket storre specifika ytarean och uppnas trots dessa legeringars mycket hoga smaltpunkt: 2 100-2 500 °C. Preferably the content is less than 10% by weight, more preferably less than 8% by weight, even more preferably less than 6% by weight, most preferably less than 4% by weight. weight percent, and preferably only a minority of the oxygen content comes from molybdenum oxide which has not been reduced, i.e. a briquette containing Mo0x, where x <0.5. Preferably, substantially all of the molybdenum oxide is reduced to Mo, i.e. where x is around 0. Has the remaining oxygen content comes mainly from oxides in the molybdenum oxide powder and the iron-containing powder which is responsible for reducing, for example oxides of Si, Ca, Al and Mg. Using purer grades of the molybdenum oxide powder, the jam-containing powder and the carbon-containing powder, the oxygen content of the briquettes can, if desired, be increased by 2% by weight. However, since many of these oxides which are responsive to reduction can be handled in steel malt metallurgy (for example by being deposited in the slag phase), they may be allowed in the jam- and molybdenum-containing briquette. The lower limit of acid can be about 0% by weight, but normally the oxygen is at least 1% by weight, more often at least 2% by weight. 14 The molybdenum content of the briquettes can be regulated by varying the relative proportions of the molybdenum oxide powder in relation to the iron-containing powder. For substantially completely reduced briquettes (i.e. briquettes containing MoOx dar x <0.5), the molybdenum content is preferably controlled to the range of 60-95% by weight. More lecture the Mo content is in the range of 65-95% by weight, most preferably the Mo content is in the range 70-95% by weight. Surprisingly, there has been a very high dissolution rate for reduced briquettes with a molybdenum content of 80-95% by weight. This result is due to the much larger specific surface area and is achieved despite the very high melting point of these alloys: 2,100-2,500 ° C.

Genom att koltillsatsen balanseras är det mojligt att reglera kolhalten i de reducerade briketterna till mindre an 5 viktprocent, mindre an 2 viktprocent, mindre an 1 viktprocent, mindre an 0,5 viktprocent eller mindre an 0,1 viktprocent. Briketter med lag kolhalt kan exempelvis anvandas vid legering av stal med lag kolhalt. Emellertid kan det inom vissa anvandningsomraden, exempelvis vid produktion av stal med hog kolhalt eller gjutjarn, vara onskvart att ha en kolhalt i intervallet 1-5 viktprocent. By balancing the carbon additive, it is possible to regulate the carbon content of the reduced briquettes to less than 5% by weight, less than 2% by weight, less than 1% by weight, less than 0.5% by weight or less than 0.1% by weight. Low carbon briquettes can be used, for example, in the alloying of low carbon steels. However For example, in certain areas of use, for example in the production of steels with a high carbon content or cast iron, it may be desirable to have a carbon content in the range 1-5% by weight.

Briketternas jarnhalt är fOretradesvis inom intervallet 1-20 viktprocent, mer fOredraget 2-10 viktprocent, mest foredraget 2-5 viktprocent. Jarnhalten i briketterna kan regleras genom att de relatiya proportionerna av det jarnhaltiga pulvret varieras i relation till molybdenoxidpulvret. The iron content of the briquettes is preferably in the range of 1-20% by weight, more preferably 2-10% by weight, most preferably 2-5% by weight. The iron content of the briquettes can be regulated by varying the relatiya proportions of the ferrous powder in relation to the molybdenum oxide powder.

De reducerade briketterna kan vara kostnadseffektiva substitut for Mo03-pulver eller standard-FeMo vid legering i smaltforfaranden, med hansyn till pris och/eller utbyte av Mo-tillsatsen i smdltan. Normalt skulle sadan tillsats kunna goras exempelvis i en elektrisk ljusbagsugn och exempelvis utgora en Mo-tillsats i rostfritt stak yerktygsstal eller snabbstal. The reduced briquettes can be cost-effective substitutes for MoO3 powder or standard FeMo for alloying in smelting processes, with a view to price and / or exchange of The Mo additive in the melt. Normally, such an addition could be made, for example, in one electric candle baking oven and, for example, constitute a Mo additive in stainless steel yarktygsstal or faststal.

Beroende pa pulverblandningens renhet kan briketterna innehalla ytterligare grundamnen inklusive oxider som är svara att reducera. Andra grundamnen forutom Mo, Fe, C och 0 kan tillatas upp till mindre an 15 viktprocent. Foretradesvis är den totala kvantiteten av andra grundamnen utover 0, C, Mo och Fe mindre an 10 viktprocent, mer foredraget mindre an 7 viktprocent. Kvantiteten av andra grundamnen bestams huvudsakligen av renheten hos molybdentrioxiden, men kan aven komma fran fororeningar i det jarnhaltiga pulvret, det kolhaltiga pulvret och fran reaktioner med amnen i den omgivande atmosfaren under uppvarmning, reduktion eller kylning Med anvandning av hogrena kvaliteter av molybdentrioxid, jarnhaltigt pulver och det kolhaltiga pulvret kan den totala kvantiteten av andra grundamnen utover 0, C, Mo och Fe, om sa onskas, hallas lagre an 1 viktprocent. Grundamnen fran gruppen Si, Ca, Al och Mg är, om de ingar i briketterna, huvudsakligen bundna som oxider. Exempelvis kan, i en stalsmalta, kisel bundet som kiseloxider, vara lattare att hantera an kisel som är upplost i legeringens gitter. De andra grundamnena kan i vissa utforingsformer vara begransade till minst 1 viktprocent eller till minst 2 viktprocent. Andra grundamnen omfattar fororeningar. Depending on the purity of the powder mixture, the briquettes may contain additional elements including oxides that are responsible for reducing. Other basic substances besides Mo, Fe, C and 0 can be allowed up to less than 15% by weight. Preferably, the total quantity of other elements in addition to 0, C, Mo and Fe is less than 10% by weight, more preferably less than 7% by weight. The quantity of other elements is mainly determined by the purity of the molybdenum trioxide, but may also come from impurities in the ferrous powder, the carbonaceous powder and from reactions with The substances in the ambient atmosphere during heating, reduction or cooling Using high-grade grades of molybdenum trioxide, ferrous powder and the the carbonaceous powder, the total quantity of other elements in addition to 0, C, Mo and Fe, if desired, can be kept lower by 1% by weight. The basic elements of the group Si, Ca, Al and Mg, if present in the briquettes, are mainly bound as oxides. For example, in a steel malt, silicon bound as silicon oxides may be easier to handle than silicon which is dissolved in the lattice of the alloy. The other basic elements may be in certain embodiments limited to at least 1% by weight or to at least 2% by weight. Other elements include pollutants.

FOretrddesvis begransas i vissa utfdringsformer de andra grundamnena till, i viktprocent: max 2 N, mer foredraget max 1 N, max 1 S, mer foredraget max 0,5 S, max 2 Al, mer foredraget max 1,5 Al, max 2 Mg, mer foredraget max 1 Mg, max 2 Na, mer foredraget max 1 Na, max 4 Ca, mer foredraget max 2 Ca, max 6 Si, mer foredraget max 3 Si, max 1 K, mer foredraget max 0,5 K, max 1 Cu, mer foredraget max 0,5 Cu, max 1 Pb, mer foredraget max 0,1 Pb, max 1 W, mer foredraget max 0,1 W, max 1 V, mer fOredraget max 0,1 V, och aterstaende grunddmnen utgor foretradesvis hogst 0,5 var, mer foredraget hogst 0,1 var, mest foredraget hogst 0,05 var. Preferably, in some embodiments, the other elements are limited to, by weight percent: max 2 N, more lecture max 1 N, max 1 S, more lecture max 0.5 S, max 2 Al, more lecture max 1.5 Al, max 2 Mg, more lecture max 1 Mg, max 2 Na, more lecture max 1 Na, max 4 Ca, more lecture max 2 Ca, max 6 Si, more lecture max 3 Si, max 1 K, more lecture max 0.5 K, max 1 Cu, more lecture max 0.5 Cu, max 1 Pb, more lecture max 0.1 Pb, max 1 W, more lecture max 0.1 W, max 1 V, more Lecture max 0.1 V, and the remaining basic amounts preferably amount to a maximum of 0.5 each, more preferably a maximum of 0.1 was, most preferred felling 0.05 was.

I vissa utforingsformer är halten Si i viktprocent i intervallet 0,5-3, halten Ca i intervallet 0,3-2, halten Al i intervallet 0,1-1, och/eller halten Mg i intervallet 0,1-1. In some embodiments, the content of Si in weight percent is in the range of 0.5-3, the content of Ca i the range 0.3-2, the content Al in the range 0.1-1, and / or the content Mg in the range 0.1-1.

Foretradesvis är grundamnena i gruppen Si, Ca, Al och Mg, om de ingar, till minst viktprocent bundna som oxider i briketterna, foretradesvis till minst 90 viktprocent. Preferably, the basic substances in the group Si, Ca, Al and Mg, if present, are at least weight percent bound as oxides in the briquettes, preferably to at least 90 weight percent.

Kvavehalten beror huvudsakligen pa kvavenivan i atmosfaren under reduktion och kylning av briketterna. Genom reglering av atmosfaren i dessa moment kan kvdvehalten goras lagre an 0,5 viktprocent, foretradesvis lagre an 0,1 viktprocent och mest foredraget lagre an 0,05 viktprocent. The nitrogen content depends mainly on the nitrogen level in the atmosphere during reduction and cooling of the briquettes. By regulating the atmosphere at these moments, the nitrogen content can be made lower than 0.5% by weight, preferably lower by 0.1% by weight and most preferably lower by 0.05% by weight.

De reducerade briketterna har en geometrisk densitet i intervallet 1,0-4,0 g/cncil, foretradesvis 1,2-3,5 g/cm3, mer foredraget 1,2-3,0 g/cm3 . 16 En lagre densitet resulterar i hogre porositet, vilket anses ge en kortare upplosningstid for briketterna. A andra sidan okar en hogre densitet kvantiteten Mo fOr en given volym. Den geometriska densiteten är uppmatt i enlighet med ASTM 962-08. The reduced briquettes have a geometric density in the range of 1.0-4.0 g / cm 3, preferably 1.2-3.5 g / cm 3, more preferably 1.2-3.0 g / cm 3. 16 A lower density results in higher porosity, which is considered to give a shorter dissolution time for the briquettes. On the other hand, a higher density increases the quantity Mo for a given volume. The geometric density is measured in accordance with ASTM 962-08.

Claims (21)

1. êÄ7.5S.9.15 10.i I25 12.30 EB 18 A process according ta any one of claims í-š, whcarein the briquettšng is perførnred at a briquetting pressure in the range of SÜ-š G00 kgfcrnê, preferabíy 106-560 kgienü. A. process according to any one of claíms 15, vvhereiza the briqrzeitírxg is performed at abriquetting pressure in the range of 1000-10900 kgícmíš, preferably 2000-56-90 icg/'cmlA process zaccørding to any one of ciaínzs fifšgfvvhereín :he method further ínciudes thesåep: e) cooiing the reduced bršquettes in a nerroxidísing airnosphere to a tempzarzrmre below 200 ”C , :nare preferabljgf bßløw 150 °C, preferabíy in an inert atmospšrere. é”-' x A rocess accordšufl to an one of ciaims ï-ïífwïrerein the rnoi' bcíenum oxide owders Y P contains 50~8G % by vfeighí ef Mo. š A process according to any one of claims Ifåfsæfhereizz a: iaast 90% hy ufeight thepartšcles of the molybdenum øxicie powder' pass through a test síeve having ncxsninašaperture size-s of 300 pmm and at least 50 912» by Weight of the particïes of thenxoiyladenuna oxide powder pass thmugh a tesï sieve having nerninaï aperture sizes of125 run. a Ü;_: \.- , A process zzccerdisxg to any one of cšaíntrs Lâfwvhereín the iron containing poxvder' cornains at ieast 80 % by wveight of Fe, preferabíy at šeast 90 wt%, nxore preferabšy atšeast 95 wt%, mest prefembšy' at âeast 99% by *weight A process according to any ene ofclaims lßéïfxvherein a: least 90% by wešgšrt :haparticšes of the iron containing pmvder pass through a test sieve having xrmrxinašaperture sízes ef 125 gem and ai least S0 % by vzeight sf the pariícies of the šrorzcontaining powder pass through a test sieve having nornínai aperture sizes of 45 pm. VE» A process according to any one of claíms l;_}.-~ifi xvhereirr at least 9G % by weight. of theparïícles of the carbcmacecrus powder' pass throrsgh a test sieve having nominaš aperiuresšzes ef 125 gm and at least 50 % by weight of the parïícies of the carbonaceozss powder pass âhrough a test Sie-ve šæavšng nominaí aperture sízcs of 45 gsm 2G 3G 14. »aL!! 16. Yi. '§S. 19. 19 ._ åflš g i:A process according to any ene of claims hl-êf., wšxerein the carbonancous pøxvder ischosen from the group corssšstirzg of: sub-bítuxninoxxs cozzi-s, bitumixxous coaís, anthracite, lignize, Coke, petzfoleun: cake, and bio~carbozas in pariícuíar charcoal. . A process acccrdšrzg to any one of cíašms 144, wherein the carbonaceeus powder is chosen fiom the group consšstizag of: som, carbon black, and activatecš carbon. A. process according to :my ene ofclainxs P15 wfhereín adding in step a) dry matter comprísíng in svcígšfi %: š-ÅS .íron containing powder; 5*25 carbonaccous pins/der; Ûpíionaily 0.146 iubríczzrxt :indier binder andlur slag former; and íasslance 50-90 rnoiybdcnum cxídc powder. A pressas according ta claím 16, Wherein the liquid of step a) is adcíecicin amount of í-IÜ % by xveight of the added dry matter, Iron :md moïybcšcaxum containing green briquettes having a dry nnaiter composition inweighzß/b of:1-15 åren containing powder;5-25 carbenaceous pcvxder;Gptionaiiy(li-EQ iubz-ícant and/or binder and/or slag former; and baïance 50--90 :noïybdenusxï oxšde powder. Green briquettes according' to claim 18, 'wherešxx the briquettes have a geomctric density in the range of 1.041) g/cnzß, preíbrably I.2~3\5 gfcmß, more preferaïsly LZí-ÄO g/cnf. 2G. Rcduced iron and :noïybzienazm centašnizzg bríqazettes having a cornpøsitior: in Weight % of:í-LZÛ Fc;less than IÛ O; less than 19 CZ;