Iron and molybdenum containing pellets

Abstract

Iron and molybdenum containing pellets and a process for producing the pellets are disclosed. A green pellet is produced from mixing an iron containing powder, a molybdenum oxide powder, and a carbonaceous powder. The green pellets can be reduced at a temperature in the range of 400-1500° C. The pellets can be briquetted.

1 . A process for producing iron and molybdenum containing pellets including the steps of:
 a) mixing an iron containing powder, a molybdenum oxide powder, and a carbonaceous powder;   b) adding a liquid, and optionally one or more of a binder and a slag former to the mixture, and pelletizing to provide a plurality of green pellets; and   c) optionally drying the green pellets to reduce the moisture content to less than 10% by weight.   
     
     
         2 . A process according to  claim 1  including at least one of the steps of:
 d) heat treating the green pellets at a temperature in the range of 400-800° C. during at least 20 minutes; and 
 e) reducing the pellets derived from step c) or d) at a temperature in the range of 800-1500° C. during at least 10 minutes. 
 
     
     
         3 . A process according to  claim 2 , wherein the heat treating step d) and/or the reducing step e) is performed in a furnace supplied with an inert or reducing gas. 
     
     
         4 . A process according to  claim 3 , wherein the heat treating step d) and/or the reducing step e) is performed at an operating pressure in the range of 0.1-5 atm. 
     
     
         5 . A process according to  claim 4 , wherein the heat treating step d) and/or the reducing step e) is performed at an operating pressure in the range of 1.05-1.2 atm. 
     
     
         6 . A process according to  claim 5 , wherein the inert or reducing gas is supplied counter flow. 
     
     
         7 . A process according to  claim 1 , including drying the green pellets to a moisture content less than 5% by weight. 
     
     
         8 . A process according to  claim 7 , wherein the green pellets are dried at a temperature in the range of 50-250° C. 
     
     
         9 . A process according to  claim 2 , wherein the method includes one or more of the following steps:
 f) cooling the pellets in a non-oxidising atmosphere to a temperature below 200° C. in an inert atmosphere;   g) crushing and/or grinding the pellets;   h) sieving the crushed and/or ground pellets;   i) hot briquetting at a temperature in the range of 250-1000° C.; and   j) agglomerating pellets to pellet agglomerates comprising 2-300 pellets.   
     
     
         10 . A process according to  claim 1 , wherein the molybdenum oxide powder contains 50-80% by weight of Mo. 
     
     
         11 . A process according to  claim 1 , wherein at least 90% by weight of particles of the molybdenum oxide powder pass through a test sieve having nominal aperture sizes of 300 μm and at least 50% by weight of particles of the molybdenum oxide powder pass through a test sieve having nominal aperture sizes of 125 μm. 
     
     
         12 . A process according to  claim 1 , wherein the iron containing powder contains at least 80% by weight of Fe. 
     
     
         13 . A process according to  claim 1 , wherein at least 90% by weight of particles of the iron containing powder pass through a test sieve having nominal aperture sizes of 125 μm and at least 50% by weight of particles of the iron containing powder pass through a test sieve having nominal aperture sizes of 45 μm. 
     
     
         14 . A process according to  claim 1 , wherein at least 90% by weight of particles of the carbonaceous powder pass through a test sieve having nominal aperture sizes of 125 μm and at least 50% by weight of particles of the carbonaceous powder pass through a test sieve having nominal aperture sizes of 45 μm. 
     
     
         15 . A process according to  claim 1 , wherein the carbonaceous powder is chosen from the group consisting of: sub-bituminous coals, bituminous coals, anthracite, lignite, coke, petroleum coke, and bio-carbons. 
     
     
         16 . A process according to  claim 1 , wherein the carbonaceous powder is chosen from the group consisting of: soot, carbon black, and activated carbon. 
     
     
         17 . Iron and molybdenum containing green pellets having a geometric density less than 4.0 g/cm 3  and having a dry matter composition in weight-% of:
 1-25 Fe;   15-40 O;   5-25 C;   less than 15 of other elements, and   balance at least 30 Mo.   
     
     
         18 . Green pellets according to  claim 17  fulfilling at least one of the following conditions:
 a moisture rate less than 10% by weight; 
 a compression strength in the range of 200-1000 N/pellet; 
 a geometric density of at least 1.2 g/cm 3 ; 
 a geometric density less than 3.5 g/cm 3 ; and 
 a diameter in the range of 3-35 mm. 
 
     
     
         19 . Reduced iron and molybdenum containing pellets having a geometric density less than 4.0 g/cm 3  and having a composition in weight % of:
 2-30 Fe;   less than 30 O;   less than 20 C;   less than 15 of other elements; and   balance at least 40 Mo.   
     
     
         20 . Reduced pellets according to  claim 19 , wherein the pellets contains in weight %:2-25 Fe. 
     
     
         21 . Reduced pellets according to  claim 19 , wherein the pellets contain in weight %: less than 10 of other elements. 
     
     
         22 . Reduced pellets according to  claim 19 , wherein the pellets contain in weight %: at least 1 of other elements. 
     
     
         23 . Reduced pellets according to  claim 19 , wherein the pellets contain in weight %: at least 60 Mo. 
     
     
         24 . Reduced pellets according to  claim 19 , wherein the pellets contain in weight %: less than 10 O. 
     
     
         25 . Reduced pellets according to  claim 19 , wherein the pellets contain in weight %: less than 5 C. 
     
     
         26 . Reduced pellets according to  claim 19 , wherein the pellets contain in weight %:80-95 Mo. 
     
     
         27 . Reduced pellets according to  claim 19 , wherein the pellets contain in weight %:
 10-20 O, and   5-15 C.   
     
     
         28 . Reduced pellets according to  claim 19 , fulfilling at least one of the following conditions:
 a compression strength in the range of 200-1000 N/pellet;   a geometric density of at least 1.2 g/cm 3 ;   a geometric density less than 3.5 g/cm 3 ;   a diameter in the range of 3-30 mm.   
     
     
         29 . Reduced pellets according to  claim 28 , wherein the geometric density is in a range of 1.5 g/cm 3  to 3.2 g/cm 3 . 
     
     
         30 . Reduced iron and molybdenum containing pellets of  claim 19 , the pellets having a composition in weight % of:
 2-10 Fe;   less than 10 O;   less than 5 C;   less than 10 of other elements; and   balance at least 70 Mo.   
     
     
         31 . Reduced iron and molybdenum containing pellets of  claim 19 , the pellets having a composition in weight % of:
 2-10 Fe;   less than 4 O;   less than 0.5 C;   less than 7 of other elements; and   balance 80-95 Mo.   
     
     
         32 . A process according to  claim 2 , wherein reducing the pellets derived from step c) or d) occurs at a temperature in the range of 1000-1350° C. 
     
     
         33 . Green pellets according to  claim 17 , wherein the dry matter composition in weight-% includes:
 1.5-20 Fe;   15-30 O;   7-20 C;   less than 10 of other elements; and   balance at least 40 Mo.   
     
     
         34 . Green pellets according to  claim 17 , wherein the geometric density is in a range of 1.5 g/cm 3  to 3.2 g/cm 3 . 
     
     
         35 . A process according to  claim 1 , wherein the liquid is water. 
     
     
         36 . Reduced pellets according to  claim 19 , wherein the balance of the composition in weight % of the pellets is least 50 Mo.