DD285497A7 - FLOCKING AGENT FOR THE PRIMARY FLOODING OF SUSPENDED WATER INGREDIENTS - Google Patents

Abstract

The invention relates to a flocculant for the primary flocculation of suspended water ingredients by a temperature-induced flocculation using a flocculant mixture of linear or linear teilacyliertem polyethylenimine and alkali metal salts of anionic polymers {flocculants for suspended water constituents; temperature-induced primary flocculation; synergistic flocculant mixture; Alkali salts of anionic polymers; linear polyethyleneimine; partially acylated linear polyethylenimine}

Description

wherein the ratio n / m 1 <n / m <0 and R = CH ₃ or C ₆ H ₆ , characterized in that the flocculant from a mixture of aqueous solution of polyethylenimine and water-soluble alkali metal salts of carboxymethylcellulose with a degree of substitution> 0.6 , the polyphosphoric acid or the polyacrylic acid in the molar ratio χ of phosphate and / or carboxyl to imino groups 0.01 <x <0.9, is adjusted to an application temperature 338K <T <358K and in amounts of 10 to 200g flocculant solids, based on 10 ⁸ g suspension, is present.

Field of application of the invention

The invention relates to a flocculant for the primary flocculation of suspended particles from aqueous media.

Characteristic of the known state of the art

Inorganic primary flocculants such as ferric chloride and aluminum sulfate have been known for a long time and are used for various technical squatting operations.

The disadvantage of these inorganic flocculants is incomplete flocculation and a limited field of application.

Also known is an organic primary flocculant based on polyacrylonitrile, in which an inclusion flocculation is achieved by varying the polyampholyte used as flocculant and enveloping and sedimenting or floating in the form of very large, voluminous flakes of water constituents (DDPS217197).

The disadvantage here is the need for the dissolution of the flocculant in aggressive media (acids or bases) and the necessary pH change during Fl jckungsvorgangee.

An environmentally friendly process under mild conditions for primary flocculation by means of temperature variation by use of linear teilacyliertem and / or linear nonacylated polyethyleneimine has been described in which the high Fiockungsmitteldosierung (4-6% solution of the precipitating component) and only a partial flocculation of the suspended particles as disadvantageous proves.

Object of the invention

The aim of the invention is to develop a flocculant for primary flocculation of suspended particles in the aqueous phase which is more rational in its application and designed economically more advantageous.

Explanation of the essence of the invention

The object of the invention is to develop an improved in effect and technically easy to handle flocculant for temperature-induced primary flocculation of colloid suspended particles from aqueous systems by means of aqueous polymer blends of linear teilacyliertem or linear nichtacyliortem polyethyleneimine and an additional component.

It has been found that a mixture of linear teilacyliertem or linear nichtacyliertem Polyethy'enimin the general formula I.

Cha Cha

a o

CHa. -

- N

♦ η

in which R = CH ₃ or C ₉ C ₆ and the ratio n / m 1 <n / m <Obeträgt, surprisingly with alkali metal salts of suitable anionic polymers or mixtures thereof, such as. B. the carboxymethylcellulose, polyphosphoric acid or polyacrylic acid at temperatures> 65K, preferably 338K <T <358K, is dissolved and precipitated by Tomperaturvariation in the form of a primary flocculant suspended water constituents, with 10-20Og solid of the flocculant to 10 ^e g of the aqueous phase with pH > = 7 and a temperature T <308K with mixing is to meter. Such flocculating systems can be obtained using said anionic polymers with commercial molecular weight products.

The advantage of the invention is a more complete flocculation of suspended water ingredients with reduced flocculant use.

Ausführungsbeliplele example 1

200 ml of a mixture of a linear polyethylenimine solution according to formula I (10 g / 1000 ml of water) with a ratio n / m = 0.1 and R = CHa and sodium carboxymethylcellulose were mixed in a 100 ml slurry with suspension (1 g of whiting / 1000 ml of water) at 293K Substitution degree of 1.0, wherein the molar ratio xvon carboxyl to imino groups is apparent from the following experimental examples.

sedimented portion of the slurry suspension after 4 minutes stirring time and 2 minutes sedimentation phase = 27%

sedimented portion of the slurry suspension after stirring for 20 minutes: 56.5%

sedimented portion of the slurry suspension after stirring for 20 minutes: 24%

Example 2

200 ml of a mixture of a linear polyethylenimine solution of formula I (10 g / 1000 ml of water) with a ratio n / m = 0.1 and R = CH !, and sodium carboxymethylcetlulose were stirred into 100 ml of a slurry-chalk suspension (1 g of whiting cream / 1000 ml of water) at 293K a degree of substitution of 0.66.

Molar ratio χ of carboxyl to imino groups: χ = 0.12 sedimented portion of Schlärr.mkreidesuspension after 20 minutes stirring time: 53%.

Example 3

In 100 ml of a Celliilosesuspension (1 g / 1000 ml of water) at 293 K with stirring 200μΙ a mixture of a linear polyethylenimine solution of formula I (10g / 1000ml water) with a ratio n / m = 0.1 and R = CH ₃ and a Natriumcarboxymethylcellulose given with a degree of substitution of 1.0.

Molar ratio χ of carboxyl to imino groups: χ = 0.18 sedimented portion of the cellulosic suspension after stirring for 20 minutes: 80%.

Example 4

In 100 ml of a pulp suspension (1 g HEWETEN / 1000 ml of water) were at 293 Kii ter stirring 100μΙ a mixture of a linear polyethylenimine solution of formula I (10g / 1000ml water) with a ratio n / m = 0.1 and R = CH ₃ and Sodium carboxymethyl cellulose with a degree of substitution of 1.0.

Molar ratio χ of carboxyl to amino groups: χ = 0.18 sedimented portion of the pulp suspension after stirring for 20 minutes: 63%.

Example 5

200 ml of a mixture of a linear polyethylenimine solution of formula I (10 g / 1000 ml of water) at a ratio of n / m = 0.1 and R = C ₆ H ₅ and at 293 K were stirred into 100 ml of a slurry chill & suspension (1 g whiting cream / 1000 ml water) Sodium polyphosphate added with a degree of polymerization of 41, wherein the molar ratio χ of phosphate to imino groups is apparent from the following experimental examples.

Sedimented portion of the slurry suspension after stirring for 20 minutes: 38%

Sedimented portion of the slurry suspension after stirring for 4 minutes and sedimentation time 2 minutes: 45%

Sedimented portion of the slurry suspension after stirring for 4 minutes and sedimentation time 2 minutes: 45%

Example β In 100 ml of a slurry-chalk suspension (1 g whiting / 1000 ml of water) were stirred at 293K 200 μΙ a mixture of a linear Polyethylenimlnlösung according to formula I (10g / 1000ml water) with a ratio n / m = 0.1 and R = CH _S and Natrlumpolyacrylatsueatz given, wherein the molar ratio χ of carboxyl to imino groups is apparent from the following experimental examples.

sedimented portion of the slurry suspension after stirring for 20 minutes: 12%

Sedimented portion of the slurry suspension after stirring for 20 minutes: 18%

sedimented portion of the slurry suspension after stirring for 20 minutes: 68%

Sedimented portion of the slurry suspension after stirring for 10 minutes: 79%

Claims (1)

Claim: Flocculants for the primary flocculation of suspended water constituents in aqueous media, using linear partially acylated or linear non-acylated polyethyleneimine of the general formula I, CHa. - CHa - N - CHa - N H