CH617226A5 - Process and apparatus for the mechanical washing and cleaning of solid materials using low-phosphate or phosphate-free detergents and cleaners - Google Patents

Description

The invention is not limited to the arrangements shown. Rather, these can be supplemented f, 0 or modified in a variety of ways.

Examples

The following cation exchangers were used.

I. An exchanger obtained from 94 mol% acrylic acid and 6 mol% hexamethy-65 len-bis-acrylamide in the form of the sodium salt with a capacity of 8.2 m Val / g, an average grain size (unswollen) of 0.05 mm and swollen in water of about 0.15 mm.

617 226

5

II. A polyacrylate exchanger (Na salt) produced according to Example 2 of DOS 2 411 466 in the form of a finely ground, open-cell foam with a grain size of 0.1 mm (unswollen) and a capacity of 10.5 m Val / g.

The arrangement according to Fig. IV was used as a washing machine, equipped with a fluidized bed filter, in which the incoming washing liquid flows tangentially into the interior of a cylindrical filter container, after passing through the filter bag made of textile fabric, enters the outer filter container and from there back to the washing machine.

The wash liquor contained (in g / 1):

0.5 Na-n-dodecylbenzenesulfonate 0.17 tallow alcohol, 14-fold ethoxylated 0.27 Na tallow soap / Na behenate 1: 1 0.25 Na silicate (Na20: Si02 = 1: 3.3) 0.11 Na carboxymethyl cellulose 0.2 magnesium silicate 0.2 sodium sulfate

In one test series, the filter was charged with an exchanger, in a second series of tests (comparison) the exchanger was omitted. In addition, work was carried out in the presence of a soluble complexing agent and in the absence of such (comparative experiment).

Experimental g / 1 exchanger g / 1 additional arrangement of soiled samples was determined photometrically. The results are summarized in the following table.

example

Arrangement of exchanger

% Remission

5

B

a.B M

_

a -

55

57 52

-

b

79

80 67

c -

55

58 54

d

57

58 54

e I

76

68 54

i f I

80

70 55

2nd

g I

80

70 56

3rd

Hi

82

73 56

-

e II

77

66 54

s4

f II

81

72 46

5

g H

80

71 56

6

h II

82

73 56

a b c d e

f g h

2.5 exchangers 2.5 exchangers 2.5 exchangers 2.5 exchangers

2.5 Na triphosphate 0.4 Na triphosphate 0.4 Na triphosphate 0.4 Na citrate

0.4 Na triphosphate 0.4 Na citrate 0.4 Na triphosphate 0.4 Na citrate

The washing machine was made up of 3 kg of clean laundry and two soiled textile samples (1 kg in total):

The experiments were repeated using a detergent of the following composition (wash liquor content in g / 1).

0.5 oxo alcohol C14-C17.12-times ethoxylated 0.17 tallow alcohol, 5-times ethoxylated 25 0.27 Na-tallow soap / Na-behenate 1: 1 0.25 Na-silicate (Na20: Si02 = 1: 3.3 ) 0.11 Na carboxymethyl cellulose 0.2 magnesium silicate 0.2 sodium sulfate 30 This formulation is particularly suitable for textiles made from finished cotton and blended fabrics.

A washing arrangement according to the image was used. V, with the wash liquor first being added and the exchanger being added. After 5 minutes of pumping over, the 35 exchanger had completely collected in the fluidized bed filter. The laundry was then placed in the wash liquor and the washing process started. The other test conditions were the same as in Examples 1-6.

The results of the reflectance measurements are summarized in the following table.

example

Arrangement of exchanger

% Remission

Cotton (abbreviation B)

B

from

M

finished cotton (abbreviation a.B)

-

a -

79

68

60

Blended fabrics made of finished (abbreviation M)

45

c -

80

71

68

Cotton and polyester 1: 1

d

80

72

70

loaded. The soiling consisted of skin fat, kaolin,

_

e I

80

70

65

Iron oxide black and soot. The hardness of the power water

7

f I

82

75

74

was 16 ° dH (160 mg CaO / 1), the amount of wash liquor 201

8th

g I

82

75

73

and the washing time is 40 minutes at 90 ° C (cotton and

50 9

Hi

82

76

75

finished cotton) or 60 ° C (mixed fabric). The

e II

80

70

65

Pumping over the lye was carried out continuously with one pass

10th

f II

82

76

74

rate of 12 1 / minute. Then was followed up three times

11

g II

82

76

73

rinsed, spun and dried. The remission of the

12

h II

82

76

75

2 sheets of drawings

Claims (6)

PATENT CLAIMS 1. Method for machine washing and cleaning of solid materials using low-phosphate or phosphate-free washing and cleaning solutions in the presence of water-insoluble, calcium binding capacity of at least 2 mVal / g, the cation exchanger being a copolymer or graft polymer of olefinically unsaturated monovalent and / or polyvalent carboxylic acids, characterized in that the washing and cleaning process in the presence of 0.05 to 2 g / 1 of water-soluble, calcium ion-binding complexing agents from the class of poly- and metaphosphates, or of water-soluble, calcium ion-binding organic Complexing agent, carries out and the washing and cleaning solution continuously or intermittently by means of a ring line (4) via an adsorption device (6) which is suitable for separating the cation exchanger from the washing and cleaning liquid and the amount de s cation exchanger is dimensioned such that the residual hardness of the washing and cleaning solution is 0.5 to 20 mg CaO / 1. 2. The method according to claim 1, characterized in that the content of the washing and cleaning solution of calcium ion-binding complexing agents is measured at 0.1 to 1 g / 1. 3. The method according to claim 1 and 2, characterized in that the washing and cleaning solution is passed at least 5 times, preferably 10 to 50 times during the cleaning process through the adsorption device (6) embroidered with the cation exchanger. 4. Device for performing the method according to claim 1, characterized in that it consists of the following elements: a) a washing, cleaning or rinsing unit. b) a ring line (4) equipped with a circulation pump (5), c) at least one adsorption device (6) arranged in the ring line (4) for the exchanger used. 5. The device according to claim 4, characterized in that the ring line (4) is equipped with a branch line (8) bridging the adsorption device (6) and a valve (7) regulating the two partial flows. 6. The device according to claim 4 and 5, characterized in that the adsorption device consists of a fluidized bed filter. Washing processes are known in which the washing liquor is continuously circulated during the washing process and passed through one or more containers in which the carried dirt can settle out of the washing liquid before it is returned to the washing process. It has also already been proposed to arrange screens or filters in the liquid circuit, as a result of which coarse contaminants or objects which could possibly damage the mechanics are retained. However, since the majority of the dirt is usually dissolved or dispersed in the wash liquor, cleaning or regeneration of the wash liquor is inadequate in this way, and savings in certain washing and cleaning components, e.g. Polymer phosphates cannot be achieved without simultaneously impairing the cleaning result. In commercial laundries, it is common practice to prepare the wash liquor with softened water, for which purpose the process water is usually pretreated with an ion exchanger. Soft water, however, does not have sufficient washing power, even in the presence of detergent substances, especially since the dirt adhering to the laundry generally has considerable amounts of hardness formers, which are not sufficiently removed in the absence of limescale-binding substances, so that washing crustation progresses . It has also repeatedly been proposed to carry out the washing process in the presence of ion exchangers based on organic polymers. The exchangers should be added to the wash liquor either in the form of textile-like structures or as granular or powdery exchange resins. Textile ion exchangers, however, have only a comparatively low exchange capacity, which is why relatively large amounts of them have to be used. However, the space occupied by the ion exchanger is at the expense of the laundry to be cleaned. Unless special precautions are taken, granular to powdery exchanger resins can get caught in the tissue and are difficult to remove from them. If, as was also suggested, if one tries to enclose the exchange resins in a gauze bag to prevent precipitation on the textile fiber, the cleaning effect drops significantly. These known methods and devices suitable therefor are described, for example, in the patents DE 447 827 and 958 193 and US Pat. Nos. 3,344,633,3,681,947 and 3,003,346. 25 A method and an arrangement for carrying out the method have now been found that avoid these disadvantages and lead to an above-average cleaning result even when phosphates are not present or only in a small amount in comparison with a phosphate-rich high-performance detergent. The method according to the invention is defined in claim 1. A device suitable for carrying out this method is defined in claim 4. The cation-i5 exchangers suitable for carrying out the process are known. As such, for example, the water-insoluble copolymers of acrylic, methacrylic, crotonic, maleic, fumaric and itaconic acid with polyolefinically unsaturated compounds, as described, for example, in DOS 2 411 466. They can be present in the form of 4d swellable particles or as open-pore foams, sponges or non-woven fabrics, for example according to DOS 2 216 467 or DOS 2 307 923. Graft polymers of unsaturated carboxylic acids on natural or synthetic fibers, e.g. those of acrylic or methacrylic acid on cellulose according to US Pat. No. 3,721,627 or DOS 2,330,026. The cation exchangers can be in the form of the alkali metal salts, in particular as the sodium salt, also as the lithium, potassium or ammonium salt and as the salt of organic ammonium bases , e.g. of the mono-, di- or triethanolamine as well as in the acid form. The amount of the cation exchanger should be such that the residual hardness of the cleaning solution adjusts to a value of 0.5 to 20 mg CaO / 1 in the course of the washing process. 55 If the cation exchanger is in powdery or granular form, it is advisable to choose the particle size so that the particles in the swollen state are larger than 20 μm and in particular larger than 30 μm in order to achieve good filterability. At the top, the grain size is only limited by the f, o continuity of the exchange material and the dimensions of the adsorption device. If there is sufficient continuity, the cation exchangers can also be in piece form, for example as sponges, fleeces or in the form of a cotton ball. Finally, with sufficient continuity, the material m can itself be shaped into a filter cartridge, a filter plate or a filter cloth, so that the use of a separate filter material is unnecessary. 617 226 Clogging of the filter when using finely divided cation exchangers can also be countered and at the same time the washing process can be accelerated or the cleaning result improved and the available exchange capacity can be better utilized by keeping the exchanger inside the adsorption device in constant motion, for example by pumping around the pump Operates cleaning solution intermittently or reverses its flow direction repeatedly during the washing process. A so-called “fluidized bed filter” is preferably used, in which the turbulence of the filter content is promoted by an appropriate design of the filter, the filter container or the feed lines. According to the invention, the washing and cleaning process is carried out in the presence of small amounts of 0.05-2 g / 1 of complexing or precipitating agent for calcium. It is preferable to work with additional amounts of 0.1-1 g / 1. The inorganic complexing agents of the classes pyrophosphates, triphosphates, higher polyphosphates and metaphosphates also include their alkali metal or ammonium salts, in particular the sodium salts. Organic compounds which serve as complexing agents for calcium can be found among the polycarboxylic acids, hydroxycarboxylic acids, aminocarboxylic acids, carboxyalkyl ethers, polyanionic polymers, in particular the polymeric carboxylic acids and the phosphonic acids, these compounds being used in the form of their water-soluble salts, in particular the sodium salts will. Examples of polycarboxylic acids are dicarboxylic acids of the general formula HOOC- (CH2) n-COOH with n = 0-8, also maleic acid, methylene malonic acid, citraconic acid, mesaconic acid, itaconic acid, non-cyclic polycarboxylic acids with at least 3 carboxy groups in the molecule, e.g. Tricarb-allylic acid, aconitic acid, ethylene tetracarboxylic acid, 1,1,3,3-propanetetracarboxylic acid, 1,1,3,3,5,5, -pentane-hexacarboxylic acid, hexane hexacarboxylic acid, cyclic di- or polycarboxylic acids, e.g. Cyclopentane tetracarboxylic acid, cyclohexane hexacarbonic acid, tetrahydrofuran tetracarboxylic acid, phthalic acid, terephthalic acid, benzene tri-, tetra- or pentacarboxylic acid and meilitic acid. Examples of hydroxymono- or polycarboxylic acids are glycolic acid, lactic acid, malic acid, tartronic acid, methyl tartronic acid, gluconic acid, glyceric acid, citric acid, tartaric acid, salicylic acid. Examples of aminocarboxylic acids are glycine, glycylglycine, alanine, asparagine, glutamic acid, aminobenzoic acid, imino-dodiacetic acid or triacetic acid, hydroxyethyl-iminodiacetic acid, ethylenediamine-tetraacetic acid, hydroxyethyl-ethylenediamine-triacetic acid, polymer pentaethylene-tri-acetic acid, and diethylene-tri-acetic acid, and diethylene-tri-acetic acid, and the diethylene-tri-acetic acid, and diethylene-tri-acetic acid Aziridylcarbon acid derivative, for example of acetic acid, succinic acid, tricarbalyl acid, and subsequent saponification, or by condensation of polyamines with a molecular weight of 500 to 10,000 with chloroacetic or bromoacetic salts. Examples of carboxyalkyl ethers are 2,2-oxydisuccinic acid and other ether polycarboxylic acids, in particular polycarboxylic acids containing carboxymethyl ether groups, which include corresponding derivatives of the following polyhydric alcohols or hydroxycarboxylic acids, which may be completely or partially etherified with the glycolic acid: glycol, di or triglycols , Glycerol, di- or triglycerol, glycerol monomethyl ether, 2,2-dihydroxymethyl propanol, 1,1,1-trihydroxy methyl ethane, 1,1,1-trihydroxymethyl propane, erythritol, penta-erythritol, glycolic acid, lactic acid, tartronic acid, Methyl tartronic acid, glyceric acid, erythronic acid, malic acid, citric acid, tartaric acid, trihydroxyglutaric acid, sugar acid, mucic acid. The carboxymethyl ethers of sugar, starch and cellulose are mentioned as transition types to the polymeric carboxylic acids. Among the polymeric carboxylic acids e.g. the polymers of acrylic acid, hydroxyacrylic acid, maleic acid, itaconic acid, mesaconic acid, aconitic acid, methylene malonic acid, citraconic acid and the like, the copolymers of the abovementioned carboxylic acids with one another or with ethylenically unsaturated compounds such as ethylene, propylene, isobutylene, vinyl io alcohol, vinyl methyl ether , Furan, acrolein, vinyl acetate, acrylic amide, acrylonitrile, methacrylic acid, crotonic acid etc., such as the 1: 1 copolymers of maleic anhydride and ethylene or propylene or furan play a special role. Further polymeric carboxylic acids of the type of polyhydroxy-15 polycarboxylic acids or polyaldehydo-polycarboxylic acids are essentially substances composed of acrylic acid and acrolein units or acrylic acid and vinyl alcohol units, which are obtained by copolymerization of acrylic acid and acrolein or by polymerization of acrolein and subsequent Canniz-zaro- Reaction are optionally available in the presence of formaldehyde. Examples of phosphorus-containing organic complexing agents are alkane polyphosphonic acids, amino and hydroxyalkanopolyphosphonic acids and phosphonocarboxylic acids, such as e.g. the "5 compounds methane diphosphonic acid, propane-l, 2,3-triphosphonic acid, butane-l, 2,3,4, -tetraphosphonic acid, polyvinylphosphonic acid, l-aminoethane-l, l, -diphosphonic acid, 1-amino- than-1-phenyl-1,1, -diphosphonic acid, aminotrimethylene tri-phosphonic acid, methylamino- or ethylaminodimethylene di-111-phosphonic acid, ethylene-diaminotetramethylene-tetraphosphonic acid, l-hydroxyethane-l, l-diphosphonic acid, phosphonoacetic acid, phosphonopropionic acid, l-phosphonopropionic acid, l-phosphonopropionic acid -l, 2, -dicar-bonic acid, 2-phosphonopropane-2,3, -dicarboxylic acid, 2-phospho-nobutan-l, 2,4-tricarboxylic acid, 2-phosphonobutane-2,3,4-tricar-15 bonic acid as well Copolymers of vinylphosphonic acid and acrylic acid. The process according to the invention makes it possible, when using inorganic or organic complexes containing phosphorus or 1 xing or precipitating agents, to reduce the inorganic and / or organically bound phosphorus content of the treatment liquors to below 0.6 g / 1, preferably below 0.3 g / 1 or to work completely free of phosphorus compounds without having to forego the advantageous properties of a high-performance detergent rich in phosphate. In addition to washing textiles, which is to be regarded as the preferred field of application, the method and the device according to the invention are also suitable for use in commercial dishwashers. s "Depending on the field of application, customary surfactants in the washing and cleaning process can include cleaning-enhancing framework substances, bleaching substances and compounds that stabilize or activate such bleaching agents, graying inhibitors, optical brighteners, biocides or bac-ss teriostatic substances, enzymes, foam inhibitors, corrosion inhibitors and pH regulating agents are present. When using one or more of the aforementioned substances usually present in washing and cleaning liquors, the following concentrations are expediently observed: 0.01-2.5 g / 1 surfactant ss 0.05-2 g / 1 complexing agent 0-3 g / 1 other builder substances 0-0.4 g / 1 active oxygen or equivalent amounts of active chlorine 617 226 The pH of the treatment liquors can be in the range of 6-13, preferably 8.5-12, depending on the substrate to be washed or cleaned. The treatment temperature can be selected within a wide range and be 30-100 ° C. Since the washing and cleaning action is carried out even at low temperatures, i.e. at 30 to 40 ° C, sensitive fabrics, e.g. those made of wool or silk, wash or rinse fine porcelain with sensitive onglaze painting or gold decoration without risk of damage. The duration of washing or cleaning at the treatment temperature considered depends on the degree of contamination, the exchange rate and the delivery rate of the pumping system. It can therefore vary within wide limits, for example 5 minutes to 2 hours. It is advantageously between 10 and 60 minutes. The output of the conveyor system and the adsorption device are expediently dimensioned such that the cleaning liquid passes through the adsorption device charged with the ion exchanger at least 5 times, but preferably 10 times to about 50 times. This delivery rate should also be provided if the filter is covered by washed-up material or contaminants and has become more difficult to penetrate. It is therefore recommended to use; such pumps, which guarantee sufficient delivery capacity even at a certain counter pressure, for example one of 1-2 atm. Filter arrangements are advantageous in which the granular ion exchanger is swirled intensively, so that there are no heavier deposits on the filter during the washing process. Compared to a fixed bed arrangement of the exchanger, such a fluidized bed arrangement allows shorter washing times and the dimensioning of weaker and thus less constructive pumps. This effect can possibly be intensified by intermittent operation or flow reversal. If the adsorption device consists of a filter, its pore size depends on the grain size of the ion exchanger. Since the washed-up material or any additional filter aid to be used in turn exerts a filter effect, the pore size can be considerably larger in the interest of a low flow resistance than the grain size of the fine particles. The filter material can consist of any material, for example paper, textile fabric, ceramic or the exchange material itself. Filters made of paper or non-woven fabric are advantageously used, which are discarded together with the exchanger and the mechanical impurities removed from the laundry and retained by the filter and fluff abrasion or food residues in dishwashers. The advantage is that new exchange material with reproducible activity is used for each cleaning process. Both the ion exchanger and the filter material, as “environmentally friendly” waste, do not put any strain on the landfill or the incineration plants. On the other hand, the exchanger can also be regenerated. Regeneration is best carried out with high-proof saline solutions. The regeneration can also be carried out using solutions from the aforementioned complexing agents, but is less advisable for cost reasons and the possible wastewater pollution from the solutions applied. The device according to the invention thus consists of at least the following elements: a) a washing, cleaning or rinsing unit of conventional or modified design, b) the circulation line equipped with a circulation pump, c) at least one adsorption device (filter) arranged in the circulation line for the exchange used i shear. Figure I shows a flow diagram. The arrangement consists of the washing or cleaning unit (1), which is equipped with inlet (2) and outlet (3), the ring line (4), the circulation pump (5) and the adsorption vessel (6). Figure i II illustrates an embodiment in which, via an additional valve (7) and a branch line (8), the majority of the circulated cleaning liquid is immediately returned to the cleaning unit and only a partial flow is passed through the filter. This arrangement is intended for cleaning units in which the material to be cleaned is mechanically processed by the circulated cleaning solution by means of fixed or movable spray nozzles, such as e.g. in dishwashers and washing devices with hanging textiles i is common. In these cases, a filter arranged in the main flow would oppose the cleaning solution with an excessively high flow resistance. The valve (7) can also be operated intermittently. In continuously operating washing or spraying systems, two or more adsorption devices, which are equipped with optionally operated shut-off and emptying devices, can also be arranged. The filter can then be replaced with an exhausted exchanger without the cleaning i process must be interrupted. Figure III shows an arrangement in which part of the cleaning solution which has not yet been exhausted is transferred after use to a storage container (9) via a valve (7) and is kept for a subsequent cleaning process. Figure IV shows an arrangement as used in the examples. In addition to the circulation and adsorption device, a flow meter (10), a pressure measuring device (11) and a drain or extraction device (12) operated by a three-way valve are installed in order to test conditions, e.g. to be able to determine the degree of turbidity and pollution of the filtered liquor. Another arrangement used in the execution of the examples is shown in Figure V. It consists of a tub 45 washing machine with the tub (13), the laundry or. Spin basket (14) and a cross beater (15) for mechanical processing of the laundry. The centrifugal basket and turnstile are driven by the motor (17) via a change gear (16). The 50 circulation pump (18) also supplies the same gear. The circulated liquor passes from the tub into the circulation line (4) to the pump (18) and from there into the fluidized bed filter (20) back into the tub. After completion of the washing process, the wash liquor is discharged via the outlet (21) 55 after the pump has been reversed, the check valve (22) being closed in order to prevent the wash liquor from flowing back into the tub.