CN2125116U

CN2125116U - Electric smelting magnesia multicircuit smelting furnace

Info

Publication number: CN2125116U
Application number: CN 92222281
Authority: CN
Inventors: 李炳炎
Original assignee: Individual
Current assignee: Individual
Priority date: 1992-05-16
Filing date: 1992-05-16
Publication date: 1992-12-16

Abstract

The utility model relates to a fused magnesite smelting furnace which is used for obtaining crystalline magnesia with high purity. The utility model is mainly provided with a plurality of (three to six) three-phase graphite electrodes which are arranged inside a furnace body and are connected in parallel in star points form. The density of the electrodes of the furnace body is enlarged, so the power produced by the electrodes is increased, and the heat is further centralized. The fused magnesite smelting furnace can raise the quality of obtained complete products (or the rate of certified products) and can reduce the amount of magnesia rind and blanking. Meanwhile, the utility model can reduce heat loss and decrease energy consumption for specific yield. In addition, increased density of the electrodes is favorable for the relative equilibrium of the position of the electrodes inside the furnace body.

Description

Electric smelting magnesia multicircuit smelting furnace

The utility model belongs to hot smelting furnace field, industrial ore deposit, particularly a kind of fused magnesite smelting furnace that is used to obtain high-purity crystallized magnesia (MgO).

Traditional fused magnesite smelting furnace mostly is made up of body of heater, graphite electrode and clamping elevating mechanism thereof, electric energy supply and conditioning equipment etc.To place three (one tunnel) graphite electrodes in the body of heater to pass to the three-phase alternating current of 90～110V, 50Hz during work, the arc heat by the interpolar starting the arc is with magnesite mineral aggregate (MgCO ₃) constantly fusion, deposition, make it to be decomposed into magnesia and carbon dioxide (CO ₂↑), and under the high temperature action more than 2900 ℃, other impurity (Ca, Si, Al etc.) is all evaporated, thereby formed purity at the crystal magnesium oxide more than 97%.The existing in prior technology problem is in this area: since magnesian fusing point up to 2900 ℃, boiling point is 3600 ℃, the difference of the relative fusing point of boiling point only is 700 ℃, magnesia is high temperature thermal insulation material in addition, thermal conductivity factor is little, mobile poor after the fusion, thereby the power of fused magnesite smelting furnace can not design very greatly (power of existing apparatus all designs below 1,000 KVA) as ordinary arc furnace like that.If because the words very big as body of heater power, then electrode utmost point heart diameter of a circle also must design very greatly, such body of heater is behind the material that is used for melting heat conductibility difference, can form when the temperature in arc core district during up to the boiling point of this material (melt start vaporizer), and the phenomenon of melt temperature is located also not reach in the arc limit and the center of circle etc., cause certified products (fusion product) rate of smelting furnace not high, skin sand (semi-molten product MgO ₂) on the high side, and then also caused raw-material significant wastage.And on the other hand, the power of smelting furnace is more little, and its heat waste is lost big more, and the power consumption value of specific yield is also high more.In addition, another problem that prior art also exists is: since in the smelting process be by improve or sinking A, B, C three-phase electrode with regulate its over the ground (A, B, C three phase point are to the fused solution thing) reach the purpose of control electric current, A, B, C three-phase electrode respectively up and down process culminant star point will drift about, so also will occur being unfavorable for the balance of relative position between electrode as regulating the then also phenomenon of fluctuation thereupon of B, C phase current of A phase current.

The purpose of this utility model is according to the existing in prior technology problem, provide a kind of simple in structure, reasonable in design, can improve the power of smelting furnace and the fused magnesite multichannel that reduces the specific yield energy consumption and help electrode position relative equilibrium in body of heater smelting furnace altogether.

In order to realize the foregoing invention purpose, technical solution of the present utility model is: the fused magnesite multichannel that is provided has the graphite electrode of multichannel asterism parallel connection altogether in the smelting furnace.Device after this improves is because the density of graphite electrode increase in the body of heater, the power of its generation is increased (power that improves the back stove can reach more than 3,000 KVA), it is concentrated that heat more becomes, under the situation that electrode circle diameter does not increase, improved the quality (percentage of A-class goods) of product greatly, reduce the quantity of skin sand and blanking, promptly reduced raw-material consumption; Meanwhile, the corresponding increase-volume of the body of heater of smelting furnace is little, and the also corresponding minimizing of heat loss is so also significantly reduced the power consumption value of specific yield.In addition, because the structure after improving has the three-phase electrode of multichannel asterism parallel connection, when a certain road a certain phase current adjusted wherein, the fluctuation of other all phase current will will reduce greatly than the situation that a path electrode is only arranged, and so also just helps the balance of relative position between electrode.

Accompanying drawing 1 is the schematic cross section of a kind of example structure of the utility model.

In the structure that Fig. 1 provides, body of heater 1 is built-in with the graphite electrode 2 of three road asterism parallel connections, and during work, earlier striking is combustion-supporting between three-phase electrode A, the B of every path electrode, C, and after the mineral aggregate fusion, the fused solution of generation makes each put the arc electrode to connect naturally, and formation altogether.As the preferable scheme of other kind effect, the density of inserting of electrode 2 also can be four the tunnel, the five road or six the tunnel in the body of heater 1, and still by star-arrangement, its asterism is parallel with one another for three-phase electrode A, the B in each road, C.Label 3 expression blanking layers in the accompanying drawing, label 4 expression cladding layers.

When the smelting furnace body of heater is installed, it can be seated on the platform, body of heater is in the self-excited oscillation situation when work all the time, can reduce the number of times of smashing stove like this, improve the exhaust environment of body of heater by the shake table drive.

Claims

1, a kind of fused magnesite smelting furnace is made up of body of heater 1, graphite electrode 2 and clamping elevating mechanism thereof, electric energy supply and conditioning equipment etc., it is characterized in that having in the body of heater three-phase graphite electrode 2 of multichannel asterism parallel connection.

2, fused magnesite smelting furnace as claimed in claim 1 is characterized in that having in the body of heater three-phase graphite electrode 2 of 3～6 road asterism parallel connections.