Process for manufacturing metal powders
A process of producing metal powders by feeding a metal oxide and a reducing agent into a rotary reactor to form a mechanical fluid bed. The fluid bed is rotated with a rotation speed of about 100 rpm. The fluid bed is then heated to a reaction temperature of up to 1200° C. The pressure is then set within the rotary reactor to a pressure in a range of 0.001 bars to 2.0 bars, as a result reducing the reaction temperature to a temperature in a range of 600° C. to 1200° C. Finally, the pressure and the rotation are maintained, wherein a high value metal powder is formed without the requirement for post-grinding process steps. A product resulting from specific settings of the process include a high value molybdenum powder capable of being used as a chemical catalyst and other specialty applications specific to the metal, eliminating costly production methods.
1 . A process of producing a metal powder, comprising the steps of:
feeding a metal oxide and a reducing agent into a rotary reactor to form a mechanical fluid bed;
rotating said mechanical fluid bed with a rotation speed of about 100 rpm;
heating said mechanical fluid bed to a reaction temperature of up to 1200° C.;
setting pressure within said rotary reactor to a pressure in a range of 0.001 bars to 2.0 bars, as a result reducing said reaction temperature to a temperature in a range of 600° C. to 1200° C.; and,
maintaining said pressure and said rotation to form said metal powder.
2 . The process of claim 1 , wherein prior to the step of feeding, said metal oxide is discharged to a grinding mill.
3 . The process of claim 1 , wherein said reducing agent is selected from the group consisting of coal, hydrogen, natural gas, ammonia, carbon powder, nitrogen, and synthetic gas.
4 . The process of claim 1 , further comprising the step of cooling said metal powder to below 60° C.
5 . The process of claim 1 , wherein particles of said metal powder have a particle size in a same range of said metal oxide.
6 . The process of claim 5 , wherein at least 95% of said metal powder has said particle size in the same range as said metal oxide.
7 . The process of claim 1 , wherein said metal powder has a purity greater than or equal to metal content of said metal oxide.
8 . The process of claim 1 , further comprising the step of injecting a process gas into said mechanical fluid bed to form an off-gas.
9 . The process of claim 8 , further comprising the step of processing said off-gas through a thermal oxidizer.
10 . The process of claim 8 , wherein said process gas is selected from the group consisting of ammonia, ammonia doped with oxygen, hydrogen, and natural gas.
11 . The process of claim 8 , further comprising the step of treating said off-gas to retain CO 2 and H 2 O, leaving in a stream of only N 2 , a small amount of H 2 , and traces of CO, as a result producing a gas blanket.
12 . The process of claim 11 , further comprising the step of injecting said gas blanket into said mechanical fluid bed to prevent re-oxidation of said metal powder.
13 . The process of claim 1 , wherein said metal oxide is a fine from an ore of said metal powder.
14 . The process of claim 1 , wherein greater than 99% of said metal oxide is converted to said metal powder.
13 . A product produced from a process comprising the steps of:
feeding the metal oxide and a reducing agent into a rotary reactor to form a mechanical fluid bed;
rotating said mechanical fluid bed with a rotation speed of about 100 rpm;
heating said mechanical fluid bed to a reaction temperature in the range of 600° C.-1200° C. while maintaining a pressure within said rotary reactor in the range of 0.001 bar to 2 bar;
maintaining said pressure and said rotation, wherein said product is a high-purity metal oxide powder.
14 . The product of claim 13 , wherein further reduction of said high-purity metal oxide powder occurs while particle size distribution of said high-purity iron oxide powder is maintained even when the chemistry of the particle changes by injecting a reductant into said rotary reactor.
15 . The product of claim 13 , wherein re-oxidation of said high-purity metal oxide powder is prevented by flying ammonia into said rotary reactor, thereby producing N 2 and H 2 to act as a secondary reducing agent for said mechanical fluid bed.
16 . The product of claim 1 , wherein said secondary reducing agent is maintained until a temperature of said product reaches 60° C., after which said product is sorted and processed for utilization.
17 . The product of claim 13 , wherein further reduction of said high-purity metal oxide powder results by flying ammonia into said rotary reactor, and concurrently by flowing natural gas into said rotary reactor.
18 . A product produced from a process comprising the steps of:
feeding MoO 3 and a blend of H 2 and N 2 into a rotary reactor to form a mechanical fluid bed;
rotating said mechanical fluid bed with a rotation speed of about 100 rpm;
heating said mechanical fluid bed to a reaction temperature in the range of 620° C.-640° C. while maintaining a pressure within said rotary reactor of up to 1 bar;
maintaining said pressure and said rotation, wherein said product is a high-purity molybdenum powder.
19 . The product of claim 18 , wherein for the step of feeding, said MoO 3 and said blend are flown through said rotary reactor at a rate of 18.4 Nm 3 /hour per 1000 kg of MoO 3 .
20 . The product of claim 18 , wherein said MoO 3 and said blend of H 2 and N 2 are loaded in a quantity equal to 316 Nm 3 of H 2 and 790 Nm 3 of N 2 for every 1000 kg of MoO 3 .