CN1555944A - Copper fused mass filtering deoxygen technology - Google Patents

Abstract

A filter deoxidizing technology for molten copper features that the deoxidizing filter made of graphite or silicon carbide, and silicon nitride ceramics is installed in a temp holding furnace and the molten copper coming from smelting furnace is directly filtered for 10-60 S to decrease the content of oxygen to 5 ppm or less.

Description

Copper melts filters deoxidization technique

Technical field

What the present invention relates to is a kind of filtration deoxidization technique, and particularly a kind of copper melts filters deoxidization technique, belongs to the Metal smelting field.

Background technology

Copper is very easily oxidation in fusion process, and the melting later stage must be to the melt deoxidation, and deoxidation is one of gordian technique of copper melts purification.Reductor deoxidations such as normal employing phosphorus, magnesium, lithium, charcoal in the production, but residual phosphorus reduces the conductivity of copper strongly, can not be used for the production of conductive copper; The deoxidation products magnesium oxide viscosity of magnesium is big, forms oxide inclusion among the Yi Zaitong; Lithium costs an arm and a leg, and be difficult for preserving, and the improper meeting of consumption causes melt to inhale hydrogen; Charcoal density is little, floats on liquid level, only can generally be used for melt and cover and pre-deoxidation by the Liquid Phase Diffusion mass transfer to whole bath deoxidation.In addition, these conventional deoxy technologies generally are used for the melt deoxidation of oxygen level below 1000ppm, if adopt gas and impurity in the oxidation style removal copper melts, then understand remaining a large amount of Red copper oxide in the melt, need this moment to adopt method of deoxidation more efficiently, simultaneously melt is not produced secondary pollution.

Find by literature search, people such as Y.W.CHANG are at " METALLURGICAL TRANSACTIONS B " VOLUME 20B, delivered " Kinetics of Deoxidation ofLiquid Copper by Graphite Particles during Submerged Injection " literary composition (" dynamics research of winding-up Graphite Powder 99 deoxidation in the liquid copper " on ARPIL 1989:187 ~ 196, " metallurgical proceedings B ", Vol.20B, in April, 1989: 187～196), mention in this article employing with nitrogen as carrier, the winding-up process of graphite powder is to the melt deoxidation in the molten bath, though this method deoxidation speed is fast, but it can not be applied to common " melting-insulation " two stove continuous casting systems, and need outfit one to overlap special-purpose blowing device, gas flow control is improper to cause that easily liquid level seethes, cause melt oxidation again, nitrogen as carrier must be very dry, can make melt inhale hydrogen if contain the steam of trace.

Summary of the invention

The objective of the invention is to overcome deficiency of the prior art, provide a kind of copper melts to filter deoxidization technique, make it under the prerequisite of contaminated melt not, adopt the method for melt filtration, reduce the melt oxygen level rapidly, reach the requirement of stably manufactured oxygen free copper, and device is simple, with low cost, pollution-free.

The present invention is achieved by the following technical solutions, the inventive method is as follows: in horizontal casting or updraft continuous casting process, copper melts is filtered device for deoxidizing to be installed in the holding furnace, make strainer foraminous side in alignment connect the chute of smelting furnace and holding furnace, effusive melt all enters the thorough deoxidation of strainer in the smelting furnace, adopt graphite or silicon carbide in conjunction with silicon nitride ceramics as the strumbox material, the charcoal size range of selecting for use is 30 ~ 50mm, the filtration time of selecting for use is 10～60s, and oxygen level is reduced to below the 5ppm in the melt.

Below the present invention is done further qualification, processing step is as follows:

(1) the whole production device is made up of smelting furnace, chute, filtration device for deoxidizing and holding furnace, smelting furnace and holding furnace all adopt the line-frequency induction heating, they link to each other by chute, filtering device for deoxidizing is made up of filter box and a union lever that is attached thereto of a hollow, filter box with graphite or silicon carbide in conjunction with the silicon nitride ceramics manufacturing, on the sidewall of the left and right sides of casing, be drilled with the through hole of diameter 5～30mm, bottom surface also has the through hole of diameter 5～30mm on filter box, and device for deoxidizing immerses or the proposition melt so that filter.

(2) the incinerating charcoal is packaged in the filter box, then whole filtration unit is preheating to 250～400 ℃, remove the moisture of absorption.

(3) select for use oxidation resistant silicon carbide to be immersed in the holding furnace, guarantee that the strainer upper surface is lower than the copper liquid level, prevents graphite oxidation, and makes filter box foraminous side in alignment chute in conjunction with the filter box of silicon nitride ceramics union lever after with preheating.

(4) heating power of adjustment holding furnace makes the interior melt temperature of holding furnace remain on 1130～1150 ℃.

(5) melt in the smelting furnace is under the effect of hydraulic pressure difference, enter holding furnace through chute, and flow to strumbox from a side of filter box, and in the gap of charcoal, flowing and the melt in the holding furnace is filtered deoxidation, the melt after the filtration flows out from another side of strumbox.

The present invention compared with prior art, the technology that (1) has adopted strumbox to filter copper melts purifies copper melts.Copper melts is introduced strainer, increased the contact area of melt and filtration medium, deoxygenation can be carried out rapidly; (2) adopted graphite or silicon carbide in conjunction with silicon nitride ceramics as the strumbox material, neither pollute copper liquid and also participate in deoxidation; (3) the block charcoal of incinerating is as filtration medium and reductor, and the particle gap can not influence melt flow, and deoxidation products is the gas that is insoluble to copper, and raw material sources are wide, inexpensive; (4) adopt carborundum to make union lever in conjunction with silicon nitride material, contaminated melt not, resistance of oxidation is strong.

Embodiment

Provide following examples in conjunction with content of the present invention, adopt copper melts of the present invention to filter deoxidization technique:

(1) smelting furnace of whole production device and holding furnace all adopt the line-frequency induction heating,

(2) the incinerating charcoal is packaged in the filter box, then whole filtration unit is preheating to 250～400 ℃,

(3) select for use oxidation resistant silicon carbide to be immersed in the holding furnace, guarantee that the strainer upper surface is lower than the copper liquid level, and make filter box foraminous side in alignment chute in conjunction with the filter box of silicon nitride ceramics union lever after with preheating,

(4) heating power of adjustment holding furnace makes melt insulation in the holding furnace,

(5) melt in the smelting furnace enters holding furnace through chute under the effect of hydraulic pressure difference, flows to strumbox, flows in the gap of charcoal and the melt in the holding furnace is filtered deoxidation.

The present invention can reduce the oxygen level in the melt rapidly, and the selection of process parameters of embodiment sees following table for details:

Processing parameter	Embodiment 1	Embodiment 2	Embodiment 3
				The holding furnace temperature, ℃	????1130	????1140	????1150
The charcoal granularity, mm	????30	????40	????50
				Filtration time, s	????60	????10	????20
Before filtering [O] ippm	????3700	????370	????61
				Filter back [O] fppm	????38	????2	????4

Claims (3)

1, a kind of copper melts filters deoxidization technique, it is characterized in that, in horizontal casting or updraft continuous casting process, copper melts is filtered device for deoxidizing to be installed in the holding furnace, make strainer foraminous side in alignment connect the chute of smelting furnace and holding furnace, effusive melt all enters the thorough deoxidation of strainer in the smelting furnace, adopt graphite or silicon carbide in conjunction with silicon nitride ceramics as the strumbox material, the filtration time of selecting for use is 10～60s, and oxygen level is reduced to below the 5ppm in the melt.

2, copper melts according to claim 1 filters deoxidization technique, it is characterized in that, and following limitation of the invention further, processing step is as follows:

(1) selects production equipment, the whole production device is made up of smelting furnace, chute, filtration device for deoxidizing and holding furnace, smelting furnace and holding furnace all adopt the line-frequency induction heating, they link to each other by chute, filtering device for deoxidizing is made up of filter box and a union lever that is attached thereto of a hollow, filter box with graphite or silicon carbide in conjunction with the silicon nitride ceramics manufacturing, be drilled with the through hole of diameter 5～30mm on the sidewall of the left and right sides of casing, bottom surface also has the through hole of diameter 5～30mm on filter box;

(2) the incinerating charcoal is packaged in the filter box, then whole filtration unit is preheating to 250 ~ 400 ℃, remove the moisture of absorption;

(3) be immersed in the holding furnace in conjunction with the filter box of silicon nitride ceramics union lever after with oxidation resistant silicon carbide, guarantee that the filter box upper surface is lower than the copper liquid level, prevents graphite oxidation, and makes filter box foraminous side in alignment chute preheating;

(4) heating power of adjustment holding furnace makes the interior melt temperature of holding furnace remain on 1130 ~ 1150 ℃;

(5) melt in the smelting furnace is under the effect of hydraulic pressure difference, enter holding furnace through chute, and flow to strumbox from a side of filter box, and in the gap of charcoal, flowing and the melt in the holding furnace is filtered deoxidation, the melt after the filtration flows out from another side of strumbox.

3, copper melts according to claim 1 filters deoxidization technique, it is characterized in that, as the strumbox material, the charcoal size range of selecting for use is 30 ~ 50mm in conjunction with silicon nitride ceramics for employing graphite or silicon carbide.