Note: Descriptions are shown in the official language in which they were submitted.
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TUNNEL TYPE DUAL-CYCLE VACUUM SMELTING FURNACE AND
METHOD THEREOF
FIELD OF THE INVENTION
The invention relates to a magnesium reduction device and method thereof, in
particular
to a tunnel type dual-cycle vacuum smelting furnace and method thereof.
BACKGROUND OF THE INVENTION
A major conventional method for manufacturing magnesium metal is the Pidgeon
process.
In the method, silicoferrite is used as a reductant, and a horizontal furnace
is used, the furnace
body consists of refractory bricks laid on the ground, inside the furnace is
horizontally
provided with a plurality of reduction tanks which are internally filled with
reactant pellets,
coal or gas or oil is used as a fuel, a manual feeding and unloading method is
used for
combustion and heating, the reduction tank is heated by radiant heat from a
reverberatory
furnace arranged outside the reduction tank, the radiant heat is transferred
by the reduction
tank to the reactant pellets inside the reduction tank, and heat is mutually
relay transferred
among the reactant pellets. Therefore, this is a peripheral heating method.
The conventional reduction furnace has the disadvantages of low reaction rate,
high
energy consumption, serious pollution, short service life and extremely low
safety, with
deflagration or explosion accidents occurred frequently in ignition.
SUMMARY OF THE INVENTION
For the purpose of overcoming the disadvantages of the prior art, the
invention provides a
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tunnel type dual-cycle vacuum smelting furnace and method thereof.
The technical scheme for realization of the furnace in the invention is that:
the tunnel type
dual-cycle vacuum smelting furnace includes:
A tunnel type vacuum reaction chamber, which is internally provided with a
reaction
area, an induction coil is arranged inside the reaction area, and a heat
preservation area is
arranged around the reaction area;
A silicon smelting furnace A, connected to one side of the tunnel type vacuum
reaction
chamber via an insulating pipe A, is internally provided with a refractory
coating and a
thermal-protective coating; the refractory coating is internally provided with
the induction
coil, silicon liquid in the silicon smelting furnace A flows through the
insulating pipe A into
the reaction area of the tunnel type vacuum reaction chamber;
A silicon smelting furnace B, connected to the other side of the tunnel type
vacuum
reaction chamber via an insulating pipe B, is internally provided with a
refractory coating and
a thermal-protective coating; the refractory coating is internally provided
with the induction
coil, silicon liquid in the silicon smelting furnace B flows through the
insulating pipe B into
the reaction area of the tunnel type vacuum reaction chamber;
A crystallizer or a plurality of crystallizers, arranged above the tunnel type
vacuum
reaction chamber, communicated with the reaction area of the tunnel type
vacuum reaction
chamber at the lower end thereof, and used for collecting crystals;
A forging pigment and inert gas injection pipe, respectively connected to the
insulating
pipe A and the insulating pipe B; forging pigment and inert gas inside enter
the tunnel type
vacuum reaction chamber together with silicon liquid for reaction;
An inclinable work platform, on which the tunnel type vacuum reaction chamber
and the
silicon smelting furnaces A and B are fixed, at the center of gravity on the
bottom thereof is
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provided with a rotating shaft stool, and at both ends on the bottom thereof
is respectively
provided with an ejection cylinder A and an ejection cylinder B; under the
action of the
ejection cylinder A and the ejection cylinder B, the work platform alternately
inclines, realizes
alternately circular flow of silicon liquid in the silicon smelting furnace A
and the silicon
smelting furnace B, and finishes continuous reaction;
A vacuum pump, connected to the crystallizer;
And a water pump, connected to the crystallizer.
The technical scheme of the furnace also includes:
The tunnel type vacuum reaction chamber is a steel shell, whose inner lining
is
successively provided with a refractory coating, a thermal-protective coating
and an induction
coil.
The crystallizer is provided with a cooling-off sleeve inside which is
provided with a
tapered crystallization sleeve, on the cooling-off sleeve is respectively
provided with a cool
water inlet, a cool water outlet and a vacuum port, wherein the cool water
inlet is connected to
the water pump, the cool water outlet is connected to the water tank, the
vacuum port is
connected to the vacuum pump, and the cooling-off sleeve is sealed and covered
with an end
cover on its port.
Both the silicon smelting furnace A and the silicon smelting furnace B are
respectively
provided with an upper slag-drip opening on their top edge mouths.
Both the silicon smelting furnace A and the silicon smelting furnace B are
respectively
provided with a lower slag-drip opening on their bottom surfaces.
Both the insulating pipe A and the insulating pipe B are externally provided
with a
thermal insulation layer.
The reaction area of the tunnel type vacuum reaction chamber is higher than
the silicon
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smelting furnace A and the silicon smelting furnace B.
The method for realization of the invention is as below:
Silicon liquid melted is poured into the silicon smelting furnace A or the
silicon smelting
furnace B;
The silicon liquid in the silicon smelting furnace A or the silicon smelting
furnace B
flows into the tunnel type vacuum reaction chamber through the insulating pipe
A or the
insulating pipe B;
Forging pigment and inert gas are blown into the injection pipe and enter into
the tunnel
type vacuum reaction chamber together with silicon liquid;
The tunnel type vacuum reaction chamber is heated to a temperature ranging
from 1260
C to 1900 C and vacuumed, and magnesium metal gas is generated by reaction of
the
forging pigment and silicon liquid;
Attached to the tapered crystallization sleeve, magnesium metal gas is cooled
down to
form magnesium crystal;
The silicon liquid does not flow any more when it reaches equilibrium in the
silicon
smelting furnace A and the silicon smelting furnace B; at this time, silicon
liquid in the silicon
smelting furnace A and the silicon smelting furnace B starts circular flow
alternatively by
alternatively lifting the ejection cylinder A and the ejection cylinder B,
simultaneously the
forging pigment and the inert gas are continuously flowed in for generating
magnesium
crystals by continuous reaction.
The invention has the advantages of prolonging the reaction chamber by
adoption of
tunnel type production mode, increasing the quantity of reduction tanks,
realizing cyclic
continuous operation, increasing the use ratio of heat energy, improving the
production
efficiency and reducing energy consumption.
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BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a front view of the overall structure of the invention.
FIG. 2 is a vertical view of FIG. 1.
FIG. 3 is a B-B cutaway view of FIG. 2.
FIG. 4 is a C-C cutaway view of FIG. 2.
FIG. 5 is a side view of FIG. 1, showing the work platform, the ejection
cylinder A, the
ejection cylinder B and the pivot point.
FIG. 6 is a space diagram of FIG. 1 (not including the work platform).
In the Figs., I ejection cylinder A, 2 silicon smelting furnace A, 21
induction coil, 22 upper
slag-drip opening, 23 lower slag-drip opening, 3 forging pigment and inert gas
injection pipe,
4 crystallizer, 41 cooling-off sleeve, 42 tapered crystallization sleeve, 43
cool water inlet, 44
vacuum port, 45 cool water outlet, 5 insulating pipe B, 6 silicon smelting
furnace B, 7 ejection
cylinder B, 8 tunnel type vacuum reaction tank, 81 thermal-protective coating,
82 refractory
coating, 83 reaction area, 9 rotating shaft stool, 10 rotating shaft, 11
insulating pipe A, 111
insulating layer, 12 work platform, and 13 safety valve.
DETAILED DESCRIPTION OF THE EMBODIMENTS
Further description of the invention is made in combination with the
accompanying
drawings:
Embodiment: magnesium reduction furnace
As shown in FIG. 1, the reduction furnace substantially comprises a tunnel
type vacuum
reaction chamber 8, a silicon smelting furnace (A) 2, a silicon smelting
furnace (B) 6,
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crystallizers 4, a forging pigment and inert gas injection pipe 3, and a work
platform 12; the
silicon smelting furnace (A) 2 and the silicon smelting furnace (B) 6 are
connected to two
sides of the tunnel type vacuum reaction chamber 8 via the insulating pipe (A)
11 and the
insulating pipe (B) 5, a plurality of crystallizers 4 are arranged on the
tunnel type vacuum
reaction chamber 8; the tunnel type vacuum reaction chamber 8, the silicon
smelting furnace
(A) 2 and the silicon smelting furnace (B) 6 are fixed on the work platform
12; at the center of
gravity on the bottom of the work platform 12 is provided with a rotating
shaft stool 9, and at
both ends on the bottom of the work platform 12 are respectively connected
with an ejection
cylinder (A) 1 and an ejection cylinder (B) 7; each of the crystallizers 4 is
internally provided
with a cooling-off sleeve 41 and a tapered crystallization sleeve 42, on the
crystallizers 4 is
respectively provided with a cool water inlet 43, a cool water outlet 45 and a
vacuum port 44,
wherein the cool water inlet 43 is connected to a water pump (not drawn up in
the Figs.), the
cool water outlet 45 is connected to a water tank (not drawn up in the Figs.),
the vacuum port
44 is connected to a vacuum pump (not drawn up in the Figs.), and the
insulating pipe (A) II
and the insulating pipe (B) 5 are respectively connected with a forging
pigment and inert gas
injection pipe 3.
The tunnel type vacuum reaction chamber 8 is a steel shell, which is
internally provided
with a reaction area 83, the reaction area 83 is internally provided with a
refractory coating 82
and externally provided with a thermal-protective coating 81, and an induction
coil 21 is
arranged between the refractory coating 82 and the thermal-protective coating
81.
The silicon smelting furnace (A) 2 and the silicon smelting furnace (B) 6 are
internally
provided with a refractory coating 82 and a thermal-protective coating 81, the
refractory
coating 82 is internally provided with an induction coil 21, both the silicon
smelting furnace
(A) 2 and the silicon smelting furnace (B) 6 are respectively provided with an
upper slag-drip
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opening 22 on their top edge mouths and with a lower slag-drip opening 23 on
their bottom
surfaces; the upper slag-drip opening 22 is used for draining dross, and the
lower slag-drip
opening 23 is used for draining slags remelting.
Both the insulating pipe (A) 11 and the insulating pipe (B) 5 are externally
provided with
a thermal insulation layer 111.
The tunnel type vacuum reaction chamber, the silicon smelting furnace (A) 2
and the
silicon smelting furnace (B) 6 are equivalent to intermediate frequency
furnaces.
Working Principle
Silicon liquid melted at a temperature of about 1300 C and prepared according
to a
certain proportion are poured into the silicon smelting furnace A or the
silicon smelting
furnace B; the silicon liquid is heated and flows into the tunnel type vacuum
reaction chamber
through the insulating pipe A or the insulating pipe B, forging pigment and
inert gas are blown
through the forging pigment and inert gas injection pipe into the tunnel type
vacuum reaction
chamber together with the silicon liquid when the silicon liquid flows through
the insulating
pipe A or the insulating pipe B; the tunnel type vacuum reaction chamber is
continued to be
heated to about 1600 C and vacuumized; at this time magnesium metal gas is
generated by
reaction of the forging pigment and the silicon liquid, the magnesium metal
gas flows into
crystallizers and cools down to be magnesium crystals, the silicon liquid
flows into the other
silicon smelting furnace from the tunnel type vacuum reaction chamber and does
not flow any
more when it reaches equilibrium in the silicon smelting furnace A and the
silicon smelting
furnace B; at this time, the silicon liquid in the silicon smelting furnace A
and the silicon
smelting furnace B starts circular flow alternatively by alternatively lifting
the ejection
cylinder A and the ejection cylinder B, simultaneously the forging pigment and
the inert gas
are continuously flowed in for generating magnesium crystals by continuous
reaction.
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The tunnel type vacuum reaction chamber is respectively provided with a
pressure safety
valve 13 at both sides, the pressure safety valve 13 is automatically opened
when the pressure
in the tunnel type vacuum reaction chamber exceeds a pressure of 5kg.
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