Method for smelting magnesium quickly and continuously

Abstract

A method for smelting magnesium quickly and continuously includes: preparing dolomite or magnesite with reductants and fluorite at a predetermined ratio, uniformly mixing the prepared ingredients to obtain pellets, and calcining the obtained pellets in an argon or nitrogen atmosphere; continuously feeding the high-temperature calcined pellets (without being cooled) under argon protection into a reduction furnace, and performing a high-temperature reduction reaction in a flowing argon atmosphere to obtain high-temperature magnesium steam; and enabling the high-temperature magnesium steam to be carried out of the high-temperature reduction furnace by an argon flow, and performing condensation to obtain metal magnesium. The present invention eliminates a vacuum system and a vacuum reduction tank, so that quick and continuous production of the metal magnesium is realized, the reduction time is shortened to 90 min or less, and the recovery rate of magnesium is increased to 88% or more.

Claims

1. A method for smelting magnesium quickly and continuously, comprising the following steps of: Step 1: ingredient preparing and pelletizing ingredient preparing: preparing dolomite, 75SiFe alloy and fluorite at a mass ratio of 110:(10-13):(3.0-4.0), uniformly mixing the prepared ingredients so as to obtain a mixture, and then adding soluble glass as a bonding agent which accounts for 1.0-2.0% of the total mass of the prepared ingredients and water which accounts for 2.0-5.0% of the total mass of the prepared ingredients; or, preparing dolomite, Al and fluorite at a mass ratio of 115:(10-13):(2.0-3.0), uniformly mixing the prepared ingredients so as to obtain a mixture, and then adding soluble glass as a bonding agent which accounts for 1.0-2.0% of the total mass of the prepared ingredients and water which accounts for 2.0-5.0% of the total mass of the prepared ingredients; pelletizing: uniformly mixing the prepared ingredients so as to obtain a mixture, pelletizing the mixture so as to obtain pellets with particle sizes of 5-20 mm, and naturally drying the pellets for 10-24 h; Step 2: pellet calcining placing the dried pellets in a high-temperature furnace, a rotary kiln or a fluidized bed, heating the dried pellets to 150-250 C., keeping the temperature for 30-60 min, dehydrating the dried pellets after the temperature is kept, then heating the dehydrated dried pellets to 850-1050 C. in an argon or nitrogen atmosphere, keeping the temperature, and performing calcination for 30-120 min; Step 3: continuous high-temperature reduction of calcined pellets continuously feeding the high-temperature calcined pellets without being cooled under argon protection into a closed high-temperature reduction furnace, then performing a high-temperature reduction reaction in a flowing argon atmosphere with a reduction temperature of 1300-1600 C., a reduction time of 20-90 min, and an argon flow rate of 2.0-5.0 m.sup.3/h in order to continuously obtain high-temperature magnesium steam, mixing the magnesium steam with argon gas to form a high-temperature gas mixture, and besides, continuously discharging reduction slag out of the high-temperature reduction furnace; and Step 4: condensing of high-temperature magnesium steam enabling the high-temperature magnesium steam to be carried out of the high-temperature reduction furnace by the argon flow, and to be delivered through a sealed pipeline to a condensation system for condensation so as to obtain metal magnesium.

2. A method for smelting magnesium quickly and continuously, comprising the following steps of: Step 1: ingredient preparing and pelletizing ingredient preparing: preparing magnesite, 75SiFe alloy, CaO and fluorite at a mass ratio of 45:(10-13):(16-20):(2.0-3.0), uniformly mixing the prepared ingredients so as to obtain a mixture, and then adding soluble glass as a bonding agent which accounts for 2.0-3.0% of the total mass of the prepared ingredients and water which accounts for 2.0-6.0% of the total mass of the prepared ingredients; or, preparing magnesite, Al, CaO and fluorite at a mass ratio of 48:(10-13):(15-18):(2.0-3.0), uniformly mixing the prepared ingredients so as to obtain a mixture, and then adding soluble glass as a bonding agent which accounts for 2.0-3.0% of the total mass of the prepared ingredients and water which accounts for 2.0-6.0% of the total mass of the prepared ingredients; Step 2: pellet calcining placing the dried pellets in a high-temperature furnace, a rotary kiln or a fluidized bed, heating the dried pellets to 150-250 C., keeping the temperature for 30-60 min, dehydrating the dried pellets after the temperature is kept, then heating the dehydrated dried pellets to 850-1050 C. in an argon or nitrogen atmosphere, keeping the temperature, and performing calcination for 30-120 min; Step 3: continuous high-temperature reduction of calcined pellets continuously feeding the high-temperature calcined pellets without being cooled under argon protection into a closed high-temperature reduction furnace, then performing a high-temperature reduction reaction in a flowing argon atmosphere with a reduction temperature of 1300-1600 C., a reduction time of 20-90 min, and an argon flow rate of 2.0-5.0 m.sup.3/h in order to continuously obtain high-temperature magnesium steam, mixing the magnesium steam with argon gas to form a high-temperature gas mixture, and besides, continuously discharging reduction slag out of the high-temperature reduction furnace; and Step 4: condensing of high-temperature magnesium steam enabling the high-temperature magnesium steam to be carried out of the high-temperature reduction furnace by the argon flow, and to be delivered through a sealed pipeline to a condensation system for condensation so as to obtain metal magnesium.

3. The method for smelting magnesium quickly and continuously according to claim 1, wherein the Al or 75SiFe alloy in Step 1 is replaced with composite reductants selected from one of the following three groups: (1) Al+75SiFe alloys; (2) Ca+75SiFe alloys; (3) Al+Ca+75SiFe alloy; the standard dosage of the composite reductants are: 1 mass unit of Al can be replaced with 2.2 mass units of Ca; 1 mass unit of 75SiFe alloy can be replaced with 2.2 mass units of Ca; and 1 mass unit of Al is equivalent to 1 mass unit of 75SiFe alloy.

4. The method for smelting magnesium quickly and continuously according to claim 1, wherein the condensing way in Step 4 is in direct condensation or atomizing condensation.

5. The method for smelting magnesium quickly and continuously according to claim 2, wherein the Al or 75SiFe alloy in Step 1 is replaced with composite reductants selected from one of the following three groups: (1) Al+75SiFe alloys; (2) Ca+75SiFe alloys; (3) Al+Ca+75SiFe alloy; the standard dosage of the composite reductants are: 1 mass unit of Al can be replaced with 2.2 mass units of Ca; 1 mass unit of 75SiFe alloy can be replaced with 2.2 mass units of Ca; and 1 mass unit of Al is equivalent to 1 mass unit of 75SiFe alloy.

6. The method for smelting magnesium quickly and continuously according to claim 2, wherein the condensing way in Step 4 is in direct condensation or atomizing condensation.

Description

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

(1) In the following embodiments:

(2) The adopted dolomite consists of the following compositions in percentage by mass: 21.7% of MgO, 30.5% of CaO, and the balance being CO.sub.2, and the total quantity of trace impurities is not more than 2.0%.

(3) The adopted magnesite consists of the following compositions in percentage by mass: 47.05% of MgO and the balance being CO.sub.2, and the quantity of trace impurities is not more than 1.5%.

(4) The adopted argon gas is argon gas with high purity of 99.95%.

(5) The adopted disc pelletizer has a diameter of 1000 mm, a side height h of 300 mm, an inclination angle of 45, and a rotation speed of 28 rpm.

(6) The adopted medium-frequency induction furnace has an induction furnace coil diameter of 200 mm.

(7) The reduction time referred in Step 3 of the following embodiments refers to the residence time of the calcined pellets in the high-temperature reduction zone.

Embodiment 1

(8) The method for smelting magnesium quickly and continuously specifically comprises the following steps of:

(9) Step 1: Ingredient Preparing and Pelletizing ingredient preparing: preparing dolomite, 75SiFe alloy and fluorite at a mass ratio of 110:10:3.0, and then adding soluble glass as a bonding agent which accounts for 1.0% of the total mass of the above three ingredients and water which accounts for 5.0% of the total mass of the above three ingredients; pelletizing: uniformly mixing the prepared ingredients so as to obtain a mixture, pelletizing the mixture by the disc pelletizer so as to obtain pellets with particle sizes of 5-20 mm, and naturally drying the pellets for 24 h;

(10) Step 2: Pellet Calcining placing the dried pellets in the high-temperature furnace, heating the dried pellets to 200 C., keeping the temperature for 45 min, dehydrating the dried pellets after the temperature is kept, then heating the dehydrated dried pellets to 1050 C. in an argon atmosphere, keeping the temperature, and performing calcination for 30 min;

(11) Step 3: Continuous High-Temperature Reduction of Calcined Pellets continuously feeding the high-temperature calcined pellets (without being cooled) under argon protection into the medium-frequency induction furnace through a sealed pipeline, then performing a continuous high-temperature reduction reaction in a flowing argon atmosphere with a reduction temperature of 1350 C., a reduction time of 90 min, and an argon flow rate of 4.5 m.sup.3/h in order to continuously obtain high-temperature magnesium steam, mixing the magnesium steam with argon gas to form a high-temperature gas mixture, and besides, continuously discharging reduction slag out of the medium-frequency induction furnace; and

(12) Step 4: Condensing of High-Temperature Magnesium Steam enabling the high-temperature magnesium steam to be carried out of the medium-frequency induction furnace by flowing argon stream, and then to be carried directly by the sealed pipeline into a magnesium condensing tank for circulating water cooling condensation so as to obtain metal magnesium ingots, with a metal magnesium recovery rate of 89%.

Embodiment 2

(13) The method for smelting magnesium quickly and continuously specifically comprises the following steps of:

(14) Step 1: Ingredient Preparing and Pelletizing ingredient preparing: preparing dolomite, 75SiFe alloy and fluorite at a mass ratio of 110:12:3.5, and then adding soluble glass as a bonding agent which accounts for 1.5% of the total mass of the above three ingredients and water which accounts for 5.0% of the total mass of the above three ingredients; pelletizing: uniformly mixing the prepared ingredients so as to obtain a mixture, pelletizing the mixture by the disc pelletizer so as to obtain pellets with particle sizes of 5-20 mm, and naturally drying the pellets for 24 h;

(15) Step 2: Pellet Calcining placing the dried pellets in the rotary kiln, heating the dried pellets to 200 C., keeping the temperature for 45 min, dehydrating the dried pellets after the temperature is kept, then heating the dried pellets to 1000 C. in a highly pure nitrogen atmosphere, keeping the temperature, and performing calcination for 60 min;

(16) Step 3: Continuous High-Temperature Reduction of Calcined Pellets continuously feeding the high-temperature calcined pellets (without being cooled) under argon protection into a high-temperature resistance furnace through a sealed pipeline, then performing a continuous high-temperature reduction reaction in a flowing argon atmosphere with a reduction temperature of 1450 C., a reduction time of 50 min, and an argon flow rate of 3.0 m.sup.3/h in order to continuously obtain high-temperature magnesium steam, mixing the magnesium steam with argon gas so as to form a high-temperature gas mixture, and besides, continuously discharging reduction slag out of the high-temperature resistance furnace; and

(17) Step 4: Condensing of High-Temperature Magnesium Steam enabling the high-temperature magnesium steam to be carried out of the high-temperature resistance furnace by flowing argon stream, and then to be carried directly by the sealed pipeline into a magnesium condensing tank for circulating water cooling condensation so as to obtain metal magnesium ingots, with a metal magnesium recovery rate of 90%.

Embodiment 3

(18) The method for smelting magnesium quickly and continuously specifically comprises the following steps of:

(19) Step 1: Ingredient Preparing and Pelletizing ingredient preparing: preparing dolomite, 75SiFe alloy and fluorite at a mass ratio of 110:12:4.0, and then adding soluble glass as a bonding agent which accounts for 2.0% of the total mass of the above three ingredients and water which accounts for 4.0% of the total mass of the above three ingredients; pelletizing: uniformly mixing the prepared ingredients so as to obtain a mixture, pelletizing the mixture through the disc pelletizer so as to obtain pellets with particle sizes of 5-20 mm, and naturally drying the pellets for 12 h;

(20) Step 2: Pellet Calcining placing the dried pellets in the fluidized bed, heating the dried pellets to 250 C., keeping the temperature for 30 min, dehydrating the dried pellets after the temperature is kept, then heating the dehydrated dried pellets to 950 C. in a highly pure nitrogen atmosphere, keeping the temperature, and performing calcination for 70 min;

(21) Step 3: Continuous High-Temperature Reduction of Calcined Pellets continuously feeding the high-temperature calcined pellets (without being cooled) under argon protection into a medium-frequency induction furnace through a sealed pipeline, then performing a continuous high-temperature reduction reaction in a flowing argon atmosphere with a reduction temperature of 1600 C., a reduction time of 20 min, and an argon flow rate of 5.0 m.sup.3/h in order to continuously obtain high-temperature magnesium steam, mixing the magnesium steam with argon gas to form a high-temperature gas mixture, and besides continuously discharging reduction slag out of the medium-frequency induction furnace; and

(22) Step 4: Condensing of High-Temperature Magnesium Steam enabling the high-temperature magnesium steam to be carried out of the medium-frequency induction furnace by flowing argon stream, and then to be carried directly by the sealed pipeline into a jet atomizer for atomizing condensation so as to obtain metal magnesium granules, with a metal magnesium recovery rate of 92%.

Embodiment 4

(23) The method for smelting magnesium quickly and continuously specifically comprises the following steps of:

(24) Step 1: Ingredient Preparing and Pelletizing ingredient preparing: preparing dolomite, Al and fluorite at a mass ratio of 115:10:2.0, and then adding soluble glass as a bonding agent which accounts for 1.0% of the total mass of the above three ingredients and water which accounts for 4.5% of the total mass of the above three ingredients; pelletizing: uniformly mixing the prepared ingredients so as to obtain a mixture, pelletizing the mixture through the disc pelletizer so as to obtain pellets with particle sizes of 5-20 mm, and naturally drying the pellets for 6 h;

(25) Step 2: Pellet Calcining placing the dried pellets in the rotary kiln, heating the dried pellets to 150 C., keeping the temperature for 60 min, dehydrating the dried pellets after the temperature is kept, then heating the dehydrated dried pellets to 850 C. in an argon atmosphere, keeping the temperature, and performing calcination for 120 min;

(26) Step 3: Continuous High-Temperature Reduction of Calcined Pellets continuously feeding the high-temperature calcined pellets (without being cooled) under argon protection into a medium-frequency induction furnace through a sealed pipeline, then performing a continuous high-temperature reduction reaction in a flowing argon atmosphere with a reduction temperature of 1300 C., a reduction time of 90 min, and a argon flow rate of 2.0 m.sup.3/h in order to continuously obtain high-temperature magnesium steam, mixing the magnesium steam with argon gas to form a high-temperature gas mixture, and besides continuously discharging reduction slag out of the medium-frequency induction furnace; and

(27) Step 4: Condensing of High-Temperature Magnesium Steam enabling the high-temperature magnesium steam to be carried out of the medium-frequency induction furnace by flowing argon stream, and then to be carried directly by the sealed pipeline into a magnesium condensing tank for circulating water cooling condensation so as to obtain metal magnesium ingots, with a metal magnesium recovery rate of 91.5%.

Embodiment 5

(28) The method for smelting magnesium quickly and continuously specifically comprises the following steps of:

(29) Step 1: Ingredient Preparing and Pelletizing ingredient preparing: preparing dolomite, Al and fluorite at a mass ratio of 115:12:2.5, and then adding soluble glass as a bonding agent which accounts for 1.5% of the total mass of the above three ingredients and water which accounts for 3.0% of the total mass of the above three ingredients; pelletizing: uniformly mixing the prepared ingredients so as to obtain a mixture, pelletizing the mixture through the disc pelletizer so as to obtain pellets with particle sizes of 5-20 mm, and naturally drying the pellets for 2 h;

(30) Step 2: Pellet Calcining placing the dried pellets in the rotary kiln, heating the dried pellets to 220 C., keeping the temperature for 50 min, dehydrating the dried pellets after the temperature is kept, then heating the dehydrated dried pellets to 950 C. in an argon atmosphere, keeping the temperature, and performing calcination for 50 min;

(31) Step 3: Continuous High-Temperature Reduction of Calcined Pellets continuously feeding the high-temperature calcined pellets (without being cooled) under argon protection into a medium-frequency induction furnace through a sealed pipeline, then performing a continuous high-temperature reduction reaction in a flowing argon atmosphere with a reduction temperature of 1500 C., a reduction time of 45 min, and an argon flow rate of 4.2 m.sup.3/h in order to continuously obtain high-temperature magnesium steam, mixing the magnesium steam with argon gas to form a high-temperature gas mixture, and besides continuously discharging reduction slag out of the medium-frequency induction furnace; and

(32) Step 4: Condensing of High-Temperature Magnesium Steam enabling the high-temperature magnesium steam to be carried out of the medium-frequency induction furnace by flowing argon stream, and then to be carried directly by the sealed pipeline into a magnesium condensing tank for circulating water cooling condensation so as to obtain metal magnesium ingots, with a metal magnesium recovery rate of 93.0%.

Embodiment 6

(33) The method for smelting magnesium quickly and continuously specifically comprises the following steps of:

(34) Step 1: Ingredient Preparing and Pelletizing ingredient preparing: preparing dolomite, Al and fluorite at a mass ratio of 115:13:3.0, and then adding soluble glass as a bonding agent which accounts for 2.0% of the total mass of the above three ingredients and water which accounts for 2.0% of the total mass of the above three ingredients; pelletizing: uniformly mixing the prepared ingredients so as to obtain a mixture, pelletizing the mixture with a disc pelletizer so as to obtain pellets with particle sizes of 5-15 mm, and naturally drying the pellets for 20 h;

(35) Step 2: Pellet Calcining placing the dried pellets in the rotary kiln, heating the dried pellets to 180 C., keeping the temperature for 55 min, dehydrating the dried pellets after the temperature is kept, then heating the dehydrated dried pellets to 900 C. in an argon atmosphere, keeping the temperature, and performing calcination for 60 min;

(36) Step 3: Continuous High-Temperature Reduction of Calcined Pellets continuously feeding the high-temperature calcined pellets (without being cooled) under argon protection into a medium-frequency induction furnace through a sealed pipeline, then performing a continuous high-temperature reduction reaction in a flowing argon atmosphere with a reduction temperature of 1550 C., a reduction time of 20 min, and an argon flow rate of 5.0 m.sup.3/h in order to continuously obtain high-temperature magnesium steam, mixing the magnesium steam with argon gas to form a high-temperature gas mixture, and besides continuously discharging reduction slag out of the medium-frequency induction furnace; and

(37) Step 4: Condensing of High-Temperature Magnesium Steam enabling the high-temperature magnesium steam to be carried out of the medium-frequency induction furnace by flowing argon stream, and then to be carried directly by the sealed pipeline into a magnesium condensing tank for circulating water cooling condensation so as to obtain metal magnesium ingots, with a metal magnesium recovery rate of 93.5%.

Embodiment 7

(38) The method for smelting magnesium quickly and continuously specifically comprises the following steps of:

(39) Step 1: Ingredient Preparing and Pelletizing ingredient preparing: preparing magnesite, 75 SiFe alloy, CaO and fluorite at a mass ratio of 45:10:16:2.0, and then adding soluble glass as a bonding agent which accounts for 2.0% of the total mass of the above four ingredients and water which accounts for 6.0% of the total mass of the above four ingredients; pelletizing: uniformly mixing the prepared ingredients so as to obtain a mixture, pelletizing the mixture with a disc pelletizer to obtain pellets with particle sizes of 5-20 mm, and naturally drying the pellets for 18 h;

(40) Step 2: Pellet Calcining placing the dried pellets in the rotary kiln, heating the dried pellets to 200 C., keeping the temperature for 35 min, dehydrating the dried pellets after the temperature is kept, then heating the dehydrated dried pellets to 1050 C. in an argon atmosphere, keeping the temperature, and performing calcination for 40 min;

(41) Step 3: Continuous High-Temperature Reduction of Calcined Pellets continuously feeding the high-temperature calcined pellets (without being cooled) under argon protection into a medium-frequency induction furnace through a sealed pipeline, then performing a continuous high-temperature reduction reaction in a flowing argon atmosphere with a reduction temperature of 1300 C., a reduction time of 90 min, and an argon flow rate of 3.0 m.sup.3/h in order to continuously obtain high-temperature magnesium steam, mixing the magnesium steam with argon gas to form a high-temperature gas mixture, and besides continuously discharging reduction slag out of the medium-frequency induction furnace; and

(42) Step 4: Condensing of High-Temperature Magnesium Steam enabling the high-temperature magnesium steam to be carried out of the medium-frequency induction furnace by flowing argon stream, and then to be carried directly by the sealed pipeline into a jet atomizer for atomizing condensation to obtain metal magnesium granules, with a metal magnesium recovery rate of 90%.

Embodiment 8

(43) The method for smelting magnesium quickly and continuously specifically comprises the following steps of:

(44) Step 1: Ingredient Preparing and Pelletizing ingredient preparing: preparing magnesite, 75SiFe alloy, CaO and fluorite at a mass ratio of 45:12:18:2.5, and then adding soluble glass as a bonding agent which accounts for 2.5% of the total mass of the above four ingredients and water which accounts for 5.0% of the total mass of the above four ingredients; pelletizing: uniformly mixing the prepared ingredients so as to obtain a mixture, pelletizing the mixture with a disc pelletizer so as to obtain pellets with particle sizes of 10-25 mm, and naturally drying the pellets for 10 h;

(45) Step 2: Pellet Calcining placing the dried pellets in the rotary kiln, heating the dried pellets to 250 C., keeping the temperature for 40 min, dehydrating the dried pellets after the temperature is kept, then heating the dehydrated dried pellets to 1000 C. in an argon atmosphere, keeping the temperature, and performing calcination for 90 min;

(46) Step 3: Continuous High-Temperature Reduction of Calcined Pellets continuously feeding the high-temperature calcined pellets (without being cooled) under argon protection into a medium-frequency induction furnace through a sealed pipeline, then performing a continuous high-temperature reduction reaction in a flowing argon atmosphere with a reduction temperature of 1400 C., a reduction time of 50 min, and an argon flow rate of 4.0 m.sup.3/h in order to continuously obtain high-temperature magnesium steam, mixing the magnesium steam with argon gas to form a high-temperature gas mixture, and besides continuously discharging reduction slag out of the medium-frequency induction furnace; and

(47) Step 4: Condensing of High-Temperature Magnesium Steam enabling the high-temperature magnesium steam to be carried out of the medium-frequency induction furnace by flowing argon stream, and then to be carried directly by the sealed pipeline into a magnesium condensing tank for circulating water cooling condensation so as to obtain metal magnesium ingots, with a metal magnesium recovery rate of 91%.

Embodiment 9

(48) The method for smelting magnesium quickly and continuously specifically comprises the following steps of:

(49) Step 1: Ingredient Preparing and Pelletizing ingredient preparing: preparing magnesite, 75SiFe alloy, CaO and fluorite at a mass ratio of 45:13:20:3.0, and then adding soluble glass as a bonding agent which accounts for 3.0% of the total mass of the above four ingredients and water which accounts for 3.0% of the total mass of the above four ingredients; pelletizing: uniformly mixing the prepared ingredients so as to obtain a mixture, pelletizing the mixture with a disc pelletizer so as to obtain pellets with particle sizes of 5-25 mm, and naturally drying the pellets for 15 h;

(50) Step 2: Pellet Calcining placing the dried pellets in the rotary kiln, heating the dried pellets to 210 C., keeping the temperature for 50 min, dehydrating the dried pellets after the temperature is kept, then heating the dehydrated dried pellets to 950 C. in an argon atmosphere, keeping the temperature, and performing calcination for 70 min;

(51) Step 3: Continuous High-Temperature Reduction of Calcined Pellets continuously feeding the high-temperature calcined pellets (without being cooled) under argon protection into a medium-frequency induction furnace through a sealed pipeline, then performing a continuous high-temperature reduction reaction in a flowing argon atmosphere with a reduction temperature of 1600 C., a reduction time of 20 min, and an argon flow rate of 5.0 m.sup.3/h in order to continuously obtain high-temperature magnesium steam, mixing the magnesium steam with argon gas to form a high-temperature gas mixture, and besides continuously discharging reduction slag out of the medium-frequency induction furnace; and

(52) Step 4: Condensing of High-Temperature Magnesium Steam enabling the high-temperature magnesium steam to be carried out of the medium-frequency induction furnace by flowing argon stream, and then to be carried directly by the sealed pipeline into a magnesium condensing tank for circulating water cooling condensation so as to obtain metal magnesium ingots, with a metal magnesium recovery rate of 95%.

Embodiment 10

(53) The method for smelting magnesium quickly and continuously specifically comprises the following steps of:

(54) Step 1: Ingredient Preparing and Pelletizing ingredient preparing: preparing magnesite, Al, CaO and fluorite at a mass ratio of 48:10:15:2.0, and then adding soluble glass as a bonding agent which accounts for 2.0% of the total mass of the above four ingredients and water which accounts for 6.0% of the total mass of the above four ingredients; pelletizing: uniformly mixing the prepared ingredients so as to obtain a mixture, pelletizing the mixture with a disc pelletizer to obtain pellets with particle sizes of 5-25 mm, and naturally drying the pellets for 8 h;

(55) Step 2: Pellet Calcining placing the dried pellets in the rotary kiln, heating the dried pellets to 200 C., keeping the temperature for 50 min, dehydrating the dried pellets after the temperature is kept, then heating the dehydrated dried pellets to 950 C. in an argon atmosphere, keeping the temperature, and performing calcination for 120 min;

(56) Step 3: Continuous High-Temperature Reduction of Calcined Pellets continuously feeding the high-temperature calcined pellets (without being cooled) under argon protection into a medium-frequency induction furnace through a sealed pipeline, then performing a continuous high-temperature reduction reaction in a flowing argon atmosphere with a reduction temperature of 1300 C., a reduction time of 80 min, and an argon flow rate of 3.5 m.sup.3/h in order to continuously obtain high-temperature magnesium steam, mixing the magnesium steam with argon gas to form a high-temperature gas mixture, and besides continuously discharging reduction slag out of the medium-frequency induction furnace; and

(57) Step 4: Condensing of High-Temperature Magnesium Steam enabling the high-temperature magnesium steam to be carried out of the medium-frequency induction furnace by flowing argon stream, and then to be carried directly by the sealed pipeline into a magnesium condensing tank for circulating water cooling condensation so as to obtain metal magnesium ingots, with an metal magnesium recovery rate of 91%.

Embodiment 11

(58) The method for smelting magnesium quickly and continuously specifically comprises the following steps of:

(59) Step 1: Ingredient Preparing and Pelletizing ingredient preparing: preparing magnesite, Al, CaO and fluorite at a mass ratio of 48:12:17:2.5, and then adding soluble glass as a bonding agent which accounts for 2.5% of the total mass of the above four ingredients and water which accounts for 2.0% of the total mass of the above four ingredients; pelletizing: uniformly mixing the prepared ingredients so as to obtain a mixture, pelletizing the mixture with a disc pelletizer to obtain pellets with particle sizes of 5-25 mm, and naturally drying the pellets for 1 h;

(60) Step 2: Pellet Calcining placing the dried pellets in the rotary kiln, heating the dried pellets to 190 C., keeping the temperature for 60 min, dehydrating the dried pellets after the temperature is kept, then heating the dehydrated dried pellets to 900 C. in an argon atmosphere, keeping the temperature, and performing calcination for 100 min;

(61) Step 3: Continuous High-Temperature Reduction of Calcined Pellets continuously feeding the high-temperature calcined pellets (without being cooled) under argon protection into a medium-frequency induction furnace through a sealed pipeline, then performing a continuous high-temperature reduction reaction in a flowing argon atmosphere with a reduction temperature of 1450 C., a reduction time of 40 min, and an argon flow rate of 4.5 m.sup.3/h in order to continuously obtain high-temperature magnesium steam, mixing the magnesium steam with argon gas to form a high-temperature gas mixture, and besides continuously discharging reduction slag out of the medium-frequency induction furnace; and

(62) Step 4: Condensing of High-Temperature Magnesium Steam enabling the high-temperature magnesium steam to be carried out of the medium-frequency induction furnace by flowing argon stream, and then to be carried directly by the sealed pipeline into a magnesium condensing tank for circulating water cooling condensation so as to obtain metal magnesium ingots, with a metal magnesium recovery rate of 94%.

Embodiment 12

(63) The method for smelting magnesium quickly and continuously specifically comprises the following steps of:

(64) Step 1: Ingredient Preparing and Pelletizing ingredient preparing: preparing magnesite, Al, CaO and fluorite at a mass ratio of 48:13:18:3.0, and then adding soluble glass as a bonding agent which accounts for 3.0% of the total mass of the above four ingredients and water which accounts for 5.0% of the total mass of the above four ingredients; pelletizing: uniformly mixing the prepared ingredients so as to obtain a mixture, pelletizing the mixture with a disc pelletizer so as to obtain pellets with particle sizes of 5-25 mm, and naturally drying the pellets for 1 h;

(65) Step 2: Pellet Calcining placing the dried pellets in the rotary kiln, heating the dried pellets to 200 C., keeping the temperature for 45 min, dehydrating the dried pellets after the temperature is kept, then heating the dehydrated dried pellets to 850 C. in an argon atmosphere, keeping the temperature, and performing calcination for 120 min;

(66) Step 3: Continuous High-Temperature Reduction of Calcined Pellets continuously feeding the high-temperature calcined pellets (without being cooled) under argon protection into a medium-frequency induction furnace through a sealed pipeline, then performing a continuous high-temperature reduction reaction in a flowing argon atmosphere with a reduction temperature of 1600 C., a reduction time of 20 min, and an argon flow rate of 5.0 m.sup.3/h in order to continuously obtain high-temperature magnesium steam, mixing the magnesium steam with argon gas to form a high-temperature gas mixture, and besides continuously discharging reduction slag out of the medium-frequency induction furnace; and

(67) Step 4: Condensing of High-Temperature Magnesium Steam enabling the high-temperature magnesium steam to be carried out of the medium-frequency induction furnace by flowing argon stream, and then to be carried directly by the sealed pipeline into a magnesium condensing tank for circulating water cooling condensation so as to obtain metal magnesium ingots, with a metal magnesium recovery rate of 96%.

Embodiment 13

(68) The method for smelting magnesium quickly and continuously specifically comprises the following steps of:

(69) Step 1: Ingredient Preparing and Pelletizing ingredient preparing: preparing dolomite, Al, 75SiFe alloy and fluorite at a mass ratio of 110:3.0:6.5:3.0, and then adding soluble glass as a bonding agent which accounts for 1.0% of the total mass of the above four ingredients and water which accounts for 4.0% of the total mass of the above four ingredients; pelletizing: uniformly mixing the prepared ingredients so as to obtain a mixture, pelletizing the mixture with a disc pelletizer so as to obtain pellets with particle sizes of 5-20 mm, and naturally drying the pellets for 24 h;

(70) Step 2: Pellet Calcining placing the dried pellets in the high-temperature furnace, heating the dried pellets to 200 C., keeping the temperature for 50 min, dehydrating the dried pellets after the temperature is kept, then heating the dehydrated dried pellets to 1000 C. in an argon atmosphere, keeping the temperature, and performing calcination for 30 min;

(71) Step 3: Continuous High-Temperature Reduction of Calcined Pellets continuously feeding the high-temperature calcined pellets (without being cooled) under argon protection into a medium-frequency induction furnace through a sealed pipeline, then performing a continuous high-temperature reduction reaction in a flowing argon atmosphere with a reduction temperature of 1350 C., a reduction time of 90 min, and an argon flow rate of 4.5 m.sup.3/h in order to continuously obtain high-temperature magnesium steam, mixing the magnesium steam with argon gas to form a high-temperature gas mixture, and besides continuously discharging reduction slag out of the medium-frequency induction furnace; and

(72) Step 4: Condensing of High-Temperature Magnesium Steam enabling the high-temperature magnesium steam to be carried out of the medium-frequency induction furnace by flowing argon stream, and then to be carried directly by the sealed pipeline into a magnesium condensing tank for circulating water cooling condensation to obtain magnesium ingots, with a metal magnesium recovery rate of 90%.

Embodiment 14

(73) The method for smelting magnesium quickly and continuously specifically comprises the following steps of:

(74) Step 1: Ingredient Preparing and Pelletizing ingredient preparing: preparing magnesite, Ca, 75SiFe alloy, CaO and fluorite at a mass ratio of 45:17.6:3:16:2.0, and then adding soluble glass as a bonding agent which accounts for 2.0% of the total mass of the above five ingredients and water which accounts for 6.0% of the total mass of the above five ingredients; pelletizing: uniformly mixing the prepared ingredients so as to obtain a mixture, pelletizing the mixture so as to obtain pellets with particle sizes of 5-20 mm, and naturally drying the pellets for 20 h;

(75) Step 2: Pellet Calcining placing the dried pellets in the rotary kiln, heating the dried pellets to 210 C., keeping the temperature for 35 min, dehydrating the dried pellets after the temperature is kept, then heating the dehydrated dried pellets to 1050 C. in an argon atmosphere, keeping the temperature, and performing calcination for 40 min;

(76) Step 3: Continuous High-Temperature Reduction of Calcined Pellets continuously feeding the high-temperature calcined pellets (without being cooled) under argon protection into a high-temperature resistance furnace through a sealed pipeline, then performing a continuous high-temperature reduction reaction in a flowing argon atmosphere with a reduction temperature of 1320 C., a reduction time of 85 min, and an argon flow rate of 3.0 m.sup.3/h in order to continuously obtain high-temperature magnesium steam, mixing the magnesium steam with argon gas to form a high-temperature gas mixture, and besides continuously discharging reduction slag out of the high-temperature resistance furnace; and

(77) Step 4: Condensing of High-Temperature Magnesium Steam enabling the high-temperature magnesium steam to be carried out of the high-temperature resistance furnace by flowing argon stream, and then to be carried directly by the sealed pipeline into a jet atomizer for direct atomizing condensation to obtain metal magnesium granules, with a metal magnesium recovery rate of 92%.

Embodiment 15

(78) The method for smelting magnesium quickly and continuously specifically comprises the following steps of:

(79) Step 1: Ingredient Preparing and Pelletizing ingredient preparing: preparing dolomite, Al, Ca, 75SiFe alloy and fluorite at a mass ratio of 110:2.7:8.8:5:4.0, and then adding soluble glass as a bonding agent which accounts for 2.0% of the total mass of the above five ingredients and water which accounts for 4.0% of the total mass of the above five ingredients; pelletizing: uniformly mixing the prepared ingredients so as to obtain a mixture, pelletizing the mixture with a disc pelletizer to obtain pellets with particle sizes of 5-20 mm, and naturally drying the pellets for 15 h;

(80) Step 2: Pellet Calcining placing the dried pellets in the fluidized bed, heating the dried pellets to 240 C., keeping the temperature for 40 min, dehydrating the dried pellets after the temperature is kept, then heating the dehydrated dried pellets to 980 C. in a highly pure nitrogen atmosphere, keeping the temperature, and performing calcination for 60 min;

(81) Step 3: Continuous High-Temperature Reduction of Calcined Pellets continuously feeding the high-temperature calcined pellets (without being cooled) under argon protection into a medium-frequency induction furnace through a sealed pipeline, then performing a continuous high-temperature reduction reaction in a flowing argon atmosphere with a reduction temperature of 1500 C., a reduction time of 20 min, and a argon flow rate of 5.0 m.sup.3/h in order to continuously obtain high-temperature magnesium steam, mixing the magnesium steam with argon gas to form a high-temperature gas mixture, and besides continuously discharging reduction slag out of the medium-frequency induction furnace; and

(82) Step 4: Condensing of High-Temperature Magnesium Steam enabling the high-temperature magnesium steam to be carried out of the medium-frequency induction furnace by flowing argon stream, and then to be carried directly by the sealed pipeline into a jet atomizer for direct atomizing condensation to obtain metal magnesium granules, with a metal magnesium recovery rate of 91%.

Embodiment 16

(83) The method for smelting magnesium quickly and continuously specifically comprises the following steps of:

(84) Step 1: Ingredient Preparing and Pelletizing ingredient preparing: preparing magnesite, Al, 75SiFe alloy, CaO and fluorite at a mass ratio of 48:4.6:7:15:2.0, and then adding soluble glass as a bonding agent which accounts for 2.0% of the total mass of the above five ingredients and water which accounts for 6.0% of the total mass of the above five ingredients; pelletizing: uniformly mixing the prepared ingredients so as to obtain a mixture, pelletizing the mixture with a disc pelletizer to obtain pellets with particle sizes of 5-25 mm, and naturally drying the pellets for 10 h;

(85) Step 2: Pellet Calcining placing the dried pellets in the rotary kiln, heating the dried pellets to 200 C., keeping the temperature for 45 min, dehydrating the dried pellets after the temperature is kept, then heating the dehydrated dried pellets to 950 C. in an argon atmosphere, keeping the temperature, and performing calcination for 120 min;

(86) Step 3: Continuous High-Temperature Reduction of Calcined Pellets continuously feeding the high-temperature calcined pellets (without being cooled) under argon protection into a medium-frequency induction furnace through a sealed pipeline, then performing a continuous high-temperature reduction reaction in a flowing argon atmosphere with a reduction temperature of 1400 C., a reduction time of 75 min, and an argon flow rate of 3.5 m.sup.3/h in order to continuously obtain high-temperature magnesium steam, mixing the magnesium steam with argon gas to form a high-temperature gas mixture, and besides continuously discharging reduction slag out of the medium-frequency induction furnace; and

(87) Step 4: Condensing of High-Temperature Magnesium Steam enabling the high-temperature magnesium steam to be carried out of the medium-frequency induction furnace by flowing argon stream, and then to be carried directly by the sealed pipeline into a magnesium condensing tank for circulating water cooling condensation to obtain metal magnesium ingots, with a metal magnesium recovery rate of 91%.

Embodiment 17

(88) The method for smelting magnesium quickly and continuously specifically comprises the following steps of:

(89) Step 1: Ingredient Preparing and Pelletizing ingredient preparing: preparing dolomite, Al, Ca, 75SiFe alloy and fluorite at a mass ratio of 115:6.6:6.6:2.5:3.0, and then adding soluble glass as a bonding agent which accounts for 2.0% of the total mass of the above five ingredients and water which accounts for 2.0% of the total mass of the above five ingredients; pelletizing: uniformly mixing the prepared ingredients so as to obtain a mixture, pelletizing the mixture with a disc pelletizer to obtain pellets with particle sizes of 5-20 mm, and naturally drying the pellets for 18 h;

(90) Step 2: Pellet Calcining placing the dried pellets in the rotary kiln, heating the dried pellets to 200 C., keeping the temperature for 50 min, dehydrating the dried pellets after the temperature is kept, then heating the dehydrated dried pellets to 900 C. in an argon atmosphere, keeping the temperature, and performing calcination for 60 min;

(91) Step 3: Continuous High-Temperature Reduction of Calcined Pellets continuously feeding the high-temperature calcined pellets (without being cooled) under argon protection into a medium-frequency induction furnace through a sealed pipeline, then performing a continuous high-temperature reduction reaction in a flowing argon atmosphere with a reduction temperature of 1500 C., a reduction time of 25 min, and an argon flow rate of 4.5 m.sup.3/h in order to continuously obtain high-temperature magnesium steam, mixing the magnesium steam with argon gas to form a high-temperature gas mixture, and besides continuously discharging reduction slag out of the medium-frequency induction furnace; and

(92) Step 4: Condensing of High-Temperature Magnesium Steam enabling the high-temperature magnesium steam to be carried out of the medium-frequency induction furnace by flowing argon stream, and then to be carried directly by the sealed pipeline into a magnesium condensing tank for circulating water cooling condensation to obtain metal magnesium ingots, with a metal magnesium recovery rate of 94%.

Embodiment 18

(93) The method for smelting magnesium quickly and continuously specifically comprises the following steps of:

(94) Step 1: Ingredient Preparing and Pelletizing ingredient preparing: preparing dolomite, Ca, 75SiFe alloy and fluorite at a mass ratio of 115:15.4:6:2.0, and then adding soluble glass as a bonding agent which accounts for 1.0% of the total mass of the above four ingredients and water which accounts for 4.5% of the total mass of the above four ingredients; pelletizing: uniformly mixing the prepared ingredients so as to obtain a mixture, pelletizing the mixture with a disc pelletizer to obtain pellets with particle sizes of 5-20 mm, and naturally drying the pellets for 10 h;

(95) Step 2: Pellet Calcining placing the dried pellets in the rotary kiln, heating the dried pellets to 180 C., keeping the temperature for 55 min, dehydrating the dried pellets after the temperature is kept, then heating the dehydrated dried pellets to 850 C. in an argon atmosphere, keeping the temperature, and performing calcination for 120 min;

(96) Step 3: Continuous High-Temperature Reduction of Calcined Pellets continuously feeding the high-temperature calcined pellets (without being cooled) under argon protection into a medium-frequency induction furnace through a sealed pipeline, then performing a continuous high-temperature reduction reaction in a flowing argon atmosphere with a reduction temperature of 1350 C., a reduction time of 80 min, and an argon flow rate of 3.5 m.sup.3/h in order to continuously obtain high-temperature magnesium steam, mixing the magnesium steam with argon gas to form a high-temperature gas mixture, and besides continuously discharging reduction slag out of the medium-frequency induction furnace; and

(97) Step 4: Condensing of High-Temperature Magnesium Steam enabling the high-temperature magnesium steam to be carried out of the medium-frequency induction furnace by flowing argon stream, and then to be carried directly by the sealed pipeline into a magnesium condensing tank for circulating water cooling condensation to obtain metal magnesium ingots, with a metal magnesium recovery rate of 93%.