HUT53031A - Process for floating loading materials from waters of cycles of paper industry - Google Patents

Abstract

A process for separating fillers from paper-making circulated water by flotation, characterised in that the paper-making circulated water is treated by 1. the addition of water-soluble salts of trivalent metal ions to give pH values of between 4.5 and 9 and 2. flotation after the addition of 5 to 100 g of anionic surfactants per m<3> of circulated water.

Description

BACKGROUND OF THE INVENTION Paper fillers for fillers of the invention! applies to a process suitable for flotation from waters.

The procedure consists of recycling the process waters

1 /. water-soluble salts of trivalent metal ions and pH

Set to between 4.5 and 9, and

2 /. 5 to 100 g of anionic surfactant are added to the cycle! to water per cubic meter of water and the process!

water flotation

Λ 1                                                                                         already     Â. 477166 / 3ZE ^{ϋ 6 Y n ύ 1} _n m m% π va PROPERTY 530.31 - song theater uinsn ..

PUBLICATION LITERATURE

COTJF

Procedure Fillers Fleet Meal Price Paper Cycle! waters

HEINKEL KOMMANDITGESELLSCHAFT AUF AKTÉN, DÜSSELDORF, FEDERAL REPUBLIC OF GERMANY

Inventors: HORNFLECK Klaus, METTMANN

Dr. VON RYBINSKI Wolfgang, DÜSSELDORF

FEDERAL REPUBLIC OF GERMANY

Date of application: £> 5. <99.

Priority: 16.7.1987 / P 57 23 500.1 /

FEDERAL REPUBLIC OF GERMANY

FIELD OF THE INVENTION The present invention relates to a process for flotation of fillers from paper-water cycles.

More particularly, the present invention relates to a process for using water-soluble salts of trivalent metal ions for flotation of fillers from recycled paper in the paper industry.

For the production of paper, a large amount of water is required, for example, to suspend fiber and excipients, to dissolve / dilute other excipients, or as zero, sealing, cooling or boiler feed water. Paper mills are therefore part of large water-consuming industrial plants. However, when using a circular process, the water requirement is greatly reduced TÜHmanns EncyclopSdie dér technischen Chemie, 17, 577. ff. / 1979 / _7.

In order to produce consistent quality paper, recycled water must be largely free of paper fibers and excipients. Paper fibers and excipients, such as fillers, glues, dyes, antifoam agents and / or dispersants, which are in the process of making paper! it is removed by filtration, flotation or sedimentation processes from the recycle water. Fiber and filler particles are often separated by flotation, in which air is pressed or aspirated through the recycle water of the papermaking machine. Small air bubbles adhere to the fiber and filler particles and form a foam on the surface of the water, which is removed by a material gripper.

However, with known flotation techniques, fillers can be removed only very imperfectly from paper recycle water. This is particularly disadvantageous when pulping paper is used in addition to wood, semi-cellulosic and / or cellulosic materials for paper production, since incomplete removal of fillers from the waste papers into water leads to difficulties in producing standardized quality papers.

The object of the present invention has been to provide a process which allows to increase the removal of fillers from the recycled water in the paper industry.

The present invention has been based on the surprising discovery that the degree of ash removal, i.e. the extent of separation of residual fillers, from paper recycle water can be substantially increased by flotation of paper water recycle with the addition of water-soluble salts of trivalent metal ions.

The present invention therefore relates to a process for flotation of fillers from paper recycled water characterized in that the paper recycled water

1 /. water-soluble salts of trivalent metal ions are added and the pH is adjusted to 4.5 to 9, followed by

2 /. 5 to 100 g of anionic surfactant per cubic meter of recycled water are added as a stock and the recycle water is flotated.

By using the water-soluble salts of the trivalent metal ions, we facilitate the ash irrigation of the paper recycle water.

Fillers commonly used in the paper industry include aluminum silicates such as kaolin or silica clay.

- 4 earths, calcium carbonate such as chalk or limestone, talc, calcium sulfate and / or barium sulfate.

In the process according to the invention, the pH is preferably between 6 and 8 in the paper recycle water. This pH is adjusted by dispensing water-soluble salts of trivalent metal ions in paper-water recycle water. Preferably, 0.05 to 1 g, in particular 0.2 to 0.5 g, of a water-soluble salt of their trivalent metal ion is added per liter of circulating water. Water-soluble sulfates, chlorides, acetates, hydroxides, phosphates and / or polyphosphates of trivalent metal ions, in particular chromium / III / sulfate, aluminum sulfate and / or iron sulfate, are suitable as water-soluble salts of trivalent metal ions. course. Aluminum sulfate is particularly preferred.

Subsequent flotation is carried out by adding 5 to 100 g, preferably 20 to 40 g, of anionic surfactant as a collecting agent to one cubic meter of recycled water.

Particularly suitable anionic surfactants are C 8 -C 24 alkyl sulfates, which are prepared by reacting C 8 -C 24 alcohols, such as lauryl alcohol or tallow fatty alcohol, with oleum, amidosulfonic acid, lucsulfonic acid or sulfur trioxide. -the curse we get by

C 8 -C 24 alcohols are reacted with 1 to 100 moles of ethylene oxide (EO), followed by lead, amidosulfonic acid, chlorosulfonic acid or sulfur trioxide such as lauryl alcohol with 30 EO sulfate, and C 3 -C 24 alkyl. ·

- 5 phenol ether sulfates prepared by reacting mono-, di- or trialkylphenol with from 1 to 100 moles of ethylene oxide and then with oleum, amidosulfonic acid, chlorine.

sulfonic acid or sulfur trioxide such as nonylphenol 4 E0-

sulfate, sulfate additionally C8-C24 alkyl and / or C3-C24 alkyl phenol ether phosphates obtained by the addition of C8-C24 alcohols and / or mono-, di- or trialkyl-phenols 1 to 100 moles of ethylene oxide, followed by treatment with polyphosphoric acids or polyphosphoric anhydride such as lauryl alcohol with 10 EO-phosphate, and C 8 -C 24 alkyl or C 3 -C 24 alkyl phenol polyglycol ether alcohols halides prepared by reacting C 8 -C 24 alkyl or C 3 -C 24 alkyl phenol polyglycol ether alcohols with maleic anhydride followed by sulfation of sodium hydrogen sulfate with, for example, nonylphenol with 10 EO sulfosuccinate;

C8-C24-alkanols or C8-C24-alkyl amines are sulfuric succinic acid derivatives, such as lauryl sulfosuccinate or talgamine sulfosuccinate; Sulfite as described in European Patent 711, C2-C24 alkylbenzene sulfonates, prepared by sulfonation of C8-C24 alkylbenzenes with concentrated sulfuric acid, oleum or sulfur trioxide, such as n-dodecyl sulfonate, -alkyl esters and / or · · · ·

- 6 sulfocarboxylic acids containing from 8 to 24 carbon atoms in the carboxylic acid moiety, such as those described in U.S. Patent 4,529,762 and German Patent Publication No. 35 13,046, C 3 -C 6 alkyl naphthalene sulfonates which are prepared by reaction of C3-C8 alcohols with naphthalene in the presence of concentrated sulfuric acid or oleum, and secondary alkane sulfonates obtained by sulfonation or sulfoxidation of paraffinic hydrocarbons and / or sulfate and / or sulfonate, e.g. . The anionic surfactants are used in the form of their water-soluble alkali and / or ammonium salts, such as the sodium and / or ammonium salts. The term ^H alkyl refers to straight and / or branched, saturated and / or unsaturated alkyl groups of natural and / or synthetic origin.

According to the process according to the invention, the paper process cycle! preferably, 0.05 to 1 g of water, especially 0.2 to 0.5 g of water-soluble trivalent metal salt is added to the water in a 1 liter cycle. water at a temperature of 20 to 60 ° C so that its pH

4.5 to 9, preferably 6-8, after the addition of the salt, and thereafter 5 to 100 g, preferably 20 to 40 g of anionic surfactant are added to the recycle water and at a temperature of 20 to 95 ° C, preferably 45 to 60 ° C. flotation. By using the process of the present invention, at least 70% by weight of filler can be removed from the paper recycle water by flotation.

The process according to the invention will be further implemented by ** ** ♦♦

- 7 examples.

Examples

1.2 g / L Filler Paper Recycle Water from a Deiking Apparatus at 45 ° C in a Denver Laboratory Flotation Cell with Sodium (12-C18) -alkylbenzenesulfonate anionic aggregate and Al1 / SO2 / 4 activator after adding, we flotated.

The results are given in the table below.

Examples amassing material Filler-discharge g / l suspension g / l suspension /% / 1 0.03 - 43 2 0.03 0.3 75

· »·· ··

Claims (7)

Claims 1. Procedure for separating fillers by flotation paper circulation! water, characterized in that water-soluble salts of trivalent metal ions are added to the paper circulation water and the pH is adjusted to a value in the range of 4.5 to 9; 5 to 100 g of anionic surfactant is added to the circulating water as one cubic meter of collecting material and the circulating water is flotated. Process according to claim 1, characterized in that after the addition of the salts of the trivalent metal ions in the paper circulation cycle water, the pH is adjusted to a value of 6-8. Method according to claim 1 or 2, characterized in that 0.05 to 1 g, preferably 0.2 to 0.5 g, of trivalent metal ion-water-soluble salt per liter of circulating water is added to the paper circulation circulating water. The process according to any one of claims 1 to 3, wherein the water-soluble salts of the trivalent metal ions are aluminum and / or ferrous sulfate, preferably aluminum sulfate. k ·· · • t · «··· ·· ··· Method according to any one of claims 1 to 4, characterized in that 20 to 40 g of anionic surfactant is added to the cycle. water per cubic meter of water. The process according to any one of claims 1 to 5, characterized in that the alkali and / or ammonium salts are C8-C24 alkyl sulphate, C8-C24 alkyl ether sulphide and / or sulpho-succinic acid of C8-C24 alcohols used as collecting materials. 7. A method of ash irrigation of paper circulation circulating water, characterized in that water-soluble salts of trivalent metal ions are added to the circulating water.