WO2000018974A1

WO2000018974A1 - Flux for molten aluminum and aluminum alloy

Info

Publication number: WO2000018974A1
Application number: PCT/JP1998/004403
Authority: WO
Inventors: Masaru Takashima; Tadashi Mantani; Tadao Meguro
Original assignee: Foun Tec Co., Ltd.
Priority date: 1998-09-30
Filing date: 1998-09-30
Publication date: 2000-04-06
Also published as: AU9280198A

Abstract

A flux for molten aluminum and aluminum alloy, containing 1 to 100% by weight of at least one member selected from among particulate vegetable organic materials and carbides thereof, the particles having a water content of at most 15% by weight. The flux may contain, in addition to the vegetable organic material, at least one optional component selected from among consolidation preventives, preservatives, antimolds, inorganic and organic fluorides, and carbonates, sulfates, nitrates and oxides of metals. The vegetable organic material is preferably one prepared by the alcoholic defatting and dehydration of a vegetable residue formed as a by-product in the processing of plants or an extraction residue of vegetable oils. Particularly preferred residues include extraction residues of buckwheat husks, walnut husks, carbonized rice husks, bean curd refuse, defatted rice bran, cotton seed oils, and sesame oils. The water content of the vegetable organic material is limited to at most 15% by weight, because this water content is preferred from the viewpoint of preventing rapid vaporization due to excessive water at the time of use of the flux and, further, preventing absorption of gas in the molten metal.

Description

Description Flux for molten aluminum and aluminum alloy

Technical field

The present invention provides a flux using a naturally-occurring vegetable organic substance as a raw material in place of a chloride / fluoride industrial chemical which is considered to cause environmental pollution, with respect to a flux used for treating molten aluminum and aluminum alloys. And help the environment. Background art

Conventional fluxes for aluminum and aluminum alloy melts are compositions in which industrial chemicals are selectively compounded in accordance with the purpose of the molten metal treatment, and halides such as chlorides and fluorides have been the main components. .

For example, Japanese Patent Application Laid-Open No. 11-23035 discloses a composition of a halide and a metal sulfate and a metal nitrate, and Japanese Patent Application Laid-Open No. 2-38559 discloses a composition containing only a halide. Japanese Patent Application Laid-Open No. 7-207376 discloses compositions of metal sulfates, carbonates and nitrates.

Further, depending on the purpose of the molten metal treatment, a treatment method in which chlorine gas is directly blown into the molten metal instead of chlorides is also performed.

In conventional fluxes for aluminum and aluminum alloy melts, there is a problem of environmental pollution derived from the main components chloride and fluoride. In particular, in recent years, environmental pollution by chlorine-based dioxins has become a major problem, and the development of alternative fluxes for chloride-containing fluxes and chlorine gas has been strongly desired. Disclosure of the invention

In order to solve the above problems, the present invention relates to a method for removing at least one of a plant organic substance and a carbide thereof having a water content not exceeding 15% by weight. An object of the present invention is to provide a flux for aluminum and aluminum alloy melts containing 100% by weight.

In addition, it is assumed that at least one other optional component of the plant organic substance is an anti-caking agent, an antiseptic, a fungicide, an inorganic or organic fluoride, a metal carbonate, a sulfate, a nitrate, or an oxide. Things.

Further, it is preferable that the vegetable organic substance is obtained by subjecting a vegetable residue produced as a by-product in the processing of a plant or a vegetable oil extraction residue to a deoiling / fat dehydrating treatment with alcohol. Defatted rice bran, cottonseed oil and sesame oil extraction residues are particularly preferred. In the present invention, the content of water contained in the vegetable organic substance is set not to exceed 15% by weight, which is preferable for controlling a rapid vaporization reaction due to excess water and gas absorption into the molten metal when used as a flux. Due to the limit. BEST MODE FOR CARRYING OUT THE INVENTION

The present invention is intended to replace halides such as chlorides and fluorides, which have been conventionally used as a main component, in a flux for molten aluminum and aluminum alloys with a part or all of plant organic substances from the viewpoint of environmental pollution measures. That is.

Vegetable organic substances use any part of the plant, as long as the content of water does not exceed 15% by weight. In order to collect as those meeting the above conditions, it is preferable to target plant residues or vegetable oil extraction residues by-produced in the processing.

The term "vegetable residue" is a collective term for by-products separated from products in agricultural, forestry product refining, sawmilling, brewing, oil pressing, and other processing steps, all of which are covered by the present invention. Things.

The extraction residue of vegetable oil, which is a form of vegetable residue, is preferably subjected to alcohol treatment in order to remove excess residual oil and water.

It is preferable to keep the residual oil content at 5% by weight or less from the viewpoint of controlling the emission. No.

In the present invention, the vegetable organic substance is subjected to the molten metal treatment of aluminum and aluminum alloys, and then carbonized and then incinerated. However, the carbonized vegetable organic substance previously carbonized is not wetted by the molten metal (has low wettability). It is useful for drying slag and improving separability from molten metal.

Among those belonging to the carbides of plant organic substances, there are burnt rice, charcoal, coke, etc., and any of them can be suitably used.

Further, in the present invention, the particle size of the botanical organic substance in the form of powder is not specified, but a practically preferable particle size range is 5 to 0.2 thighs. What is necessary is just to be in this range.

The flux of the present invention contains 1 to 100% by weight of a plant organic substance. This range corresponds to the contamination state of the molten metal, the state of the slag, and the expected treatment effect during the molten metal treatment. It is to be able to select within.

In addition, the residue when the amount of the plant organic substance is less than 100% by weight is regarded as an optional ingredient, and the contents thereof are as described above. Among them, the anti-caking agent, the antiseptic and the fungicide are the plant organic substance. It shall be used as necessary depending on the type of the material, and any type that is commonly used for that purpose may be used.

Next, inorganic or organic fluorides, metal carbonates, sulfates, nitrates, and oxides are all commonly used as conventional combustion aids for conventional fluxes, such as heat-generating agents, reaction regulators, and the like. Are selectively used according to the necessity of the processing effect.

However, chloride, which is a typical component of the conventional flux, is not adopted from the viewpoint that the present invention places importance on eliminating chlorine pollution including chlorine-based dioxins.

[Example]

For Examples 1 to 6 of the present invention, the composition of the flux and the use conditions are shown in Table 1.

In Table 1, the extraction residue of cottonseed oil and sesame oil was deoiled with alcohol. The treated one was used.

In addition, since the compounded flux was used immediately without storage, no anti-caking agent, antiseptic or fungicide was added.

In the composition of the flux, those belonging to the vegetable organic substances have

Drying was performed so as not to exceed 15% by weight, and sieving was performed so that the particle size was in the range of 5 to 0.2 mm.

Under the conditions of use in Table 1, all the melts were JIS ADC 12 (ASTM B 85 383.0), and the furnace used was a reverberatory furnace.

After these fluxes are poured into the molten metal, the slag and the molten metal are sufficiently stirred and dispersed to entangle with the slag while undergoing incineration from the carbonization stage to separate the slag and the molten metal from the molten metal in a dry state. Promoted.

As a result, it was confirmed that the product of the present invention had the same practical effects as conventional fluxes for removing slag, which are generally common.

table 1

Example (wt%)

Composition and operating conditions 1 2 3 4 5 6

(Composition)

Buckwheat husk 5

Walnut hull 55 20 30

Tofu okara 5

Skim rice bran 5

Cottonseed oil extraction residue 40 20 25 15 Sesame oil extraction residue 5

Yakimi 40 30 25 15 Coke 60 20 30 20

K ₂ C0 ₃ 5

N a 2 S 0 ₄ 20

K ₂ S0 ₄ 25 20

K N 0, 15

A1F ₃ 10 10

NaF 10

K ₂ A1F ₅ 15

S i 0 ₂ (silica sand) 5

(terms of use)

Molten t 20 20 20 15 15 15 Molten temperature ° c 760 760 760 750 750 750 Usage kg 35 35 35 25 25 25 The present invention is implemented in the form as described above, and has the following effects.

In other words, in the flux for molten aluminum and aluminum alloys, a part or all of the halides, such as chlorides and fluorides, which have been conventionally used as main components, are replaced with vegetable organic substances, thereby obtaining a halogen-based environment. It has the effect of mitigating or deterring pollution.

In particular, the elimination of the use of chlorides greatly contributes to the concern over the generation of chlorine-based dioxins and the resulting environmental pollution. Industrial applicability

INDUSTRIAL APPLICABILITY The present invention can be used as a flux for the treatment of molten aluminum and aluminum alloy (removal of slag, non-metallic inclusions, and hydrogen accompanying them).

Claims

The scope of the claims

1. A flux for molten aluminum and aluminum alloy containing 1 to 100% by weight of at least one kind of vegetable organic substance and its carbide in the form of granules having a water content not exceeding 15% by weight.

2. The flux for molten aluminum and aluminum alloy according to claim 1, wherein the vegetable organic substance is a vegetable residue produced as a by-product in the processing of plants.

3. The flux for molten aluminum and aluminum alloy according to claim 1 or 2, wherein the vegetable residue is obtained by subjecting a vegetable oil extraction residue to degreasing and dehydration treatment with alcohol.

4. The flux for molten aluminum and aluminum alloy according to claim 1, wherein the vegetable organic substance is buckwheat husk.

5. The flux for molten aluminum and aluminum alloy according to claim 1, wherein the vegetable organic substance is a walnut hull.

6. The flux for molten aluminum and aluminum alloy according to claim 1 or 2, wherein the carbides of the vegetable organic substance are burned fir.

7. The flux for molten aluminum and aluminum alloy according to claim 1, wherein the vegetable residue is tofu okara.

8. The flux for molten aluminum and aluminum alloy according to claim 1, 2 or 3, wherein the vegetable residue is defatted rice bran.

9. The flux according to claim 1, 2 or 3, wherein the vegetable residue is an extraction residue of cottonseed oil.

10. The flux according to claim 1, 2 or 3, wherein the vegetable residue is a sesame oil extraction residue.

11. The amount of at least one of vegetable organic substances and their carbides in the form of granules not containing more than 15% by weight of water is less than 1 to less than 100% by weight. Flux for aluminum and aluminum alloy melts containing at least one of preservatives, fungicides, inorganic or organic fluorides, metal carbonates, sulfates, nitrates or oxides.