Exothermic lining for metallurgical purposes and method of making the same

Claim 2

A material for making an exothermic lining, comprising, by weight, ______________________________________ 40 to 60% aluminum dross, 1 to 12% fibrous filler, 3 to 6% binder, 0.01 to 1% wetting agent selected from the group consisting of anion- active compounds, non-ionic compounds, and mixtures thereof, 7 to 25% aluminum powder and/or aluminum chips, 3 to 15% iron oxide and/or manganese dioxide, and not exceeding 6% cryolite. ______________________________________

Claim 3

The material of claim 1, wherein the fibrous filler is an inorganic filler selected from the group consisting of asbestos, glass fibre and mineral wool.

Claim 4

The material of claim 2, wherein the asbestos is amosite.

Claim 5

The material of claim 2, wherein the fibrous filler additionally comprises an organic fibrous filler selected from the group consisting of wood meal, rice straw, cellulosic fibres and synthetic fibres.

Claim 6

The material of claim 4, wherein the material contains 3 to 6% by weight of asbestos fibres and 3 to 6% by weight of wood meal.

Claim 7

The material of claim 1, wherein the wetting agent is an anionic wetting agent.

Claim 8

The material of claim 6, wherein the anionic wetting agent is selected from the group consisting of alkylbenzene sulphonates, alkyl sulphates, alkyl sulphonates and sulphated fatty acid esters.

Claim 9

The material of claim 1, wherein the wetting agent is a non-ionic wetting agent.

Claim 10

The material of claim 8, wherein the wetting agent is an alkoxylated fatty acid condensation product.

Claim 11

The material of claim 1, wherein the wetting agent component is a mixture of an anionic wetting agent and a non-ionic wetting agent.

Claim 12

The material of claim 1 wherein the solid non-fibrous constituents of the material, except the aluminium component, have a grain size from ultrafine (2 microns) up to 2.5 mm., not more than half the grains exceeding 1 mm. in size.

Claim 13

The material of claim 1, wherein the aluminium component consists of an aluminium powder of a grain size up to 2 mm. and aluminium chips up to 5 mm. in length.

Claim 14

The material of claim 1, wherein the aluminium component consists exclusively of a spherical aluminium powder coated with an oxide skin, and having a grain size up to 2 mm.

Claim 15

The material of claim 1, wherein the binder is a phenolformaldehyde resin.

Claim 16

In a method of preparing a material for making an exothermic lining, comprising, by weight, ______________________________________ 40 to 60% aluminum dross, 1 to 12% fibrous filler, 3 to 6% binder, 0.01 to 1% wetting agent selected from the group consisting of anion- active compounds, non-ionic compounds, and mixtures thereof, 7 to 25% aluminum powder and/or aluminum chips, 3 to 15% iron oxide and/or manganese dioxide, and not exceeding 6% cryolite; ______________________________________ the method steps of providing an aqueous preparation of the fibrous filler and wetting agent, adding the aluminum dross, the aluminum powder and/or chips, the iron oxide and/or manganese dioxide and the cryolite, adding the binder or components reactive to form the binder, treating the resulting mixture to render it suitable for forming into the desired shape of the lining, forming the lining and drying the formed lining to harden it.

Claim 17

In a method of preparing a material for making an exothermic lining, comprising, by weight, ______________________________________ 40 to 60% aluminum dross, 1 to 12% fibrous filler, 3 to 6% binder, 0.01 to 1% wetting agent selected from the group consisting of anion- active compounds, non-ionic compounds, and mixtures thereof, 7 to 25% aluminum powder and/or aluminum chips, 3 to 15% iron oxide and/or manganese dioxide, and not exceeding 6% cryolite; ______________________________________ the method steps of providing an aqueous preparation of the fibrous filler and wetting agent, adding the aluminum dross, the aluminum powder and/or chips, the iron oxide and/or manganese dioxide and the cryolite, adding the binder or components reactive to form the binder, treating the resulting mixture to render it suitable for forming into the desired shape of the lining, forming the lining and drying the formed lining to harden it.

Claim 18

The method of claim 15, wherein at least part of the aluminium dross is mixed with the other components before being introduced into the aqueous preparation.

Claim 19

The method of claim 15, wherein the resulting mixture is worked to a dough-like mass which is moulded on a porous or screen-like surface by squeezing or suction to form mouldings of adequate green strength for handling.

Claim 20

The method of claim 15, wherein the lining is dried at a temperature of 145° to 280° C, depending upon the nature of the binder, until the latter has set.

Claim 21

The method of claim 15, wherein the wetting agent is incorporated in the aqueous mixture in a quantity of 0.01 to 1% by weight, related to the finished product.

Claim 22

The method of claim 19, wherein the quantity of wetting agent is 0.1 to 0.5% by weight.

Claim 23

In a method of preparing a material for making an exothermic lining, comprising, by weight the components, ______________________________________ 40 to 60% aluminum dross, 1 to 12% fibrous filler, 3 to 6% binder, 0.01 to 1% wetting agent selected from the group consisting of anion- active compounds, non-ionic compounds, and mixtures thereof, 7 to 25% aluminum powder and/or aluminum chips, 3 to 15% iron oxide and/or manganese dioxide, and not exceeding 6% cryolite; ______________________________________ the method steps of preparing dry flakes or pellets of a mixture of the components, and directly pressing said flakes or pellets to form the lining.

Claim 24

In a method of preparing a material for making an exothermic lining, comprising, by weight the components, ______________________________________ 40 to 60% aluminum dross, 1 to 12% fibrous filler, 3 to 6% binder, 0.01 to 1% wetting agent selected from the group consisting of anion- active compounds, non-ionic compounds, and mixtures thereof, 7 to 25% aluminum powder and/or aluminum chips, 3 to 15% iron oxide and/or manganese dioxide, and not exceeding 6% cryolite; ______________________________________ the method steps of preparing dry flakes or pellets of a mixture of the components, and directly pressing said flakes or pellets to form the lining.