US3538004A - Process for the manufacture of detergent compositions - Google Patents

Description

5 2 9 9 LAruvum.

NOV. 3, 1970 GABLER ETAL 3,538,004

PROCESS FOR THE MANUFACTURE OF DETERGENT COMPOSITIONS Filed March 5, 1967 United States Patent 667 Int. Cl. Clld 7/56, 3/075, 7/38 us. (:1. 252-99 13 Claims ABSTRACT OF THE DISCLOSURE Production of detergent compositions containing sodium tripolyphosphate with the aid of sodium tripolyphosphate having a bulk density higher than 550 grams/liter and containing 20 to 100% phase-I, wherein pulverulent detergent components are mixed and the resulting mixture is sprayed thereafter with liquid or pasty detergent components, inside a turbulent air mixer.

The present invention relates to a process for the manufacture of pulverulent detergent compositions, wherein the individual detergent components are mixed and the resulting mixture is sprayed with wash-active substances, inside a turbulent air mixer.

It has already been proposed to produce detergents by spraying wash-active substances on pulverulent skeleton material of a detergent, inside a turbulent air mixer. The various skeleton substances should either be premixed in a mixer and introduced thereafter into the turbulent air mixer, or they should be conveyed continuously and separately from reservoirs to the turbulent air mixer, inside which wash-active substance and water are sprayed simultaneously on the pulverulent skeleton material which is thereby granulated.

Universally useful detergent compositions formulated in accordance with most recent developments in detergent chemistry contain various wash-active substances, for example, as set forth later herein and silicates, carboxymethyl cellulose, optical brighteners, perfume, sodium perborate, water and in addition thereto about 40-50% sodium tripolyphosphate as their principal ingredient. Commercial sodium tripolyphosphate is known to react with water applied thereto by spraying, while forming the hexahydrate, the reaction being accompanied by considerable evolution of heat. However, the hexahydrate is formed so reluctantly, while the hydrous, wash-active substances are sprayed on the pulverulent skeleton material, that the bulk of the heat evolved is set free only after removal of the spray product from the turbulent air mixer. The temperature of the spray product is then found to increase and readily decomposable detergent components, for example perborates, are found to decompose under the action of the heat of hydration set free subsequently. Furthermore, as a result of the sodium tripolyphosphate undergoing hydration practically after removal of the product from the turbulent air mixer, the spray product produced in the turbulent air mixer is found to be moist and to have poor flow properties provided that the said product contains the quantity of wash-active substance necessary for a detergent composition. In order to 3,538,004 Patented Nov. 3, 1970 ice obtain a useful and flowable detergent, it is necessary to subject the product to prolonged ripening.

The conventional spray-mix processes, wherein a hydrous wash-active substance is nozzle-sprayed on pulverulent skeleton material of detergents containing sodium tripolyphosphate, have all been found heretofore to entrain considerable difficulties which originate from the dissipation of the heat of hydration set free during that treatment. This is the reason why the suggested one-step production of complete detergent compositions based on sodium tripolyphosphate, more particularly of detergent compositions containing thermally readily decomposable components as an additional ingredient, for example perborates, has failed to gain commercial interest, It has therefore been necessary to use multiple-step processes to that effect.

It has now unexpectedly been found that the difliculties mentioned above can be obviated when, inside a turbulent air mixer having an associated spray device, a liquid or pasty detergent component is sprayed on sodium tripolyphosphate with a content of phase-I-material of 20 to 100%, preferably 40 to by weight.

Sodium tripolyphosphate with a content of phase-I- material as set forth above and with a bulk densit higher than 550 grams/liter, preferably higher than 600 grams and up to about 700 grams/liter, should advantageously be used for the production of detergent compositions having a high bulk density.

The process of the present invention can be used more especially for the manufacture of detergent compositions which include at least one component readily decomposable by thermal means, for example perborate. The liquid or pasty detergent components include primarily water and/ or wash-active substances.

As a result of its high hydration velocity, sodium tripolyphosphate containing phase-I-material is found to be more rapidly hydrated on being sprayed with water and wash-active substance, inside a turbulent air mixer. The heat set free is immediately dissipated by the cold air travelling continuously through the turbulent air mixer, and the spray product leaving the turbulent air mixer is found to be flowable and to have a temperature which no longer produces decomposition of the thermally readily decomposable components.

Conveniently, the air flowing through the turbulent air mixer is so controlled in temperature and/ or quantity that firstly the heat of hydration is dissipated and that secondly the temperature necessary for the hydration to occur fairly rapidly is maintained.

The liquid or pasty detergent components primarily include water and/or wash-active substances. These latter include, for example, the following anionic representatives:

Alkylaryl sulfonates, real soaps (alkali metal salts of saturated and unsaturated fatty acids, such as oleic acid, palmitic acid, stearic acid, behenic acid, coconut oil fatty acid, tallow oil fatty acid, palm kernel oil fatty acid or other fatty acids produced from natural oils and fats); salts of aminocarboxylic acids, salts of high or low-aeylated amino-carboxylic acids; fatty acid sulfates; sulfates or phosphates of fatty acid esters or amides; primary or secondary alkyl sulfates or sulfonates; sulfates, sulfonates or phosphates of esterified or etherified polyoxy compounds; and sulfates, sulfonates or phosphates of substituted polyglycol ethers;

The following non-ionic representatives, for example:

Esters or ethers of polyalcohols and alkyl, acyl or alkylaryl polyglycol ethers; and

The following cationic-active representatives, for ex ample:

Alkylamine salts; quaternary ammonium salts; alkyl pyridinium salts; ordinary and quaternary imidazoline salts; alkyl diamines and polyamines.

A considerable advantage offered by the process of the present invention resides in the fact that it admits of continuous operation, the pulverulent components being then simultaneously mixed and sprayed with the liquid or pasty detergent components.

Turbulent air mixers having associated spray devices are useful for this.

Needless to say that the pulverulent detergent components can first be premixed and the resulting mixture sprayed with the liquid or pasty components. The premixing should conveniently be achieved using a conventional air mixer, which is placed after the turbulent air mixer and may be used for adding further pulverulent components to the spray product produced inside the turbulent air mixer.

In accordance with a further feature of the present invention, the liquid or pasty detergent components can be sprayed through a plurality of nozzle rings, more particularly through two nozzle rings arranged one above the other or through two adjacent nozzle rings, ingredients containing fatty acid components being sprayed, for example, separately from the alkaline components.

The accompanying drawing is a schematic representation of an exemplary apparatus for carrying out the spraymix process inside a turbulent air mixer, the material to be sprayed travelling first through an air mixer.

The pulverulent detergent components are gently mixed in air mixer 1 using air as the mixing agent. The mixing time comprises a period of 10 to 20 seconds to ensure a uniform flow even of particularly fine pulverulent material, without formation of bridges. The mixing is achieved batchwise, each batch being fed to secondary tank 2. The

mixed material accumulating in tank 2 is conveyed through a coarse dosing sluice 3 into a tiltable balance 4 having relatively small dimensions and delivering the material to hopper 5.

Balance 4 is operatively associated with a timing relay which, after a predetermined period of time, places the balance in tilted position to deliver a char e into the hopper 5. During the same period of time, be material contained in the hopper 5 is fed through an infinitely variable bucket wheel sluice 6, a worm conveyor 7, and a flywheel 8 to a pneumatic conveyor or lift 9. The conveyor 9 delivers the material into a treatment chamber 11 through a separator 10 which discharges the material in the lower portion of the treatment chamber 11.

The interior of treatment chamber 11 is maintained under a negative pressure of 50-80 mm. water column. The conveying air for the pneumatic conveyor 9 fiows through blower 12, a return line 13 and the flywheel in a continuous cycle. By observation of an inspection glass 14, the metered quantities of material supplied by the bucket wheel sluice 6, having an infinitely variable drive, can be so regulated that hopper 5 is empty when the next charge is delivered from the balance 4. This means a very accurate control of the metered quantities of dry substance supplied, because the balance determines the constancy of weight from One batch to the next. In other words, the balance can be adjusted to deliver, for example, 5 kg. of material at intervals of 14 seconds, and the bucket wheel lock 6 can be adjusted to distribute the material, again within 14 seconds. Glass cylinder or inspection glass 15 permit this to be controlled again. Any interruption or gap in the flow of material can be equalized by adjustment of the infinitely variable drive. The flywheel 8 has the function of accelerating the material to the conveying speed to avoid a pulsating conveying movement, and also the function of reducing the pressure downstream of the bucket wheel lock, by means of an injector (not shown in the drawing).

These steps are also necessary to ensure undisturbed flow of powdered substances of different nature through the bucket wheel lock.

The negative pressure produced in the treatment chamber 11 by the low pressure blower 12, and which can be varied by the regulating flaps 16 and 16a, causes air to penetrate into the treatment chamber through an outlet 17 and through the descending material. This results in the material being catapulted upwardly in a central fountain while forming a cloud into which the spray nozzles 18, arranged as an annular set spray finely divided liquid through apertures 19.

This method of spraying prevents sprayed material from depositing on the jacket of the treatment chamber and enables a maximum surface contact and uniform distribution of the liquid in the dry material to be obtained.

The liquid is fed as usual by means of a dosing piston pump 29, including the necessary safety fittings, and is delivered through a pressure-equalizing tank 28 to the main access diaphragm valves 24. Downstream of the diaphragm valve there is arranged a pressure filter 23 which is directly in front of the associated annular nozzle ring. The liquid from the pressure filter flows through the annular distribution conduit 22 to the individual nozzle connections 20, separately closable by a hand valve 21. An outlet conduit is disposed diametrically opposite the inlet conduit, the outlet conduit being arched upwardly through 180 of arc to a level which is below the level of the individual nozzle connections from the annular conduit to the nozzle.

The conduit can be discharged through a diaphragm valve and through a lateral offtake provided with a hand valve 26. Diaphragm valves 24 and 25 are remotely controlled by a suitable control valve associated with each one thereof. The hand valve 26 serves to regulate the amount of liquid injected under the required nozzle pressure.

Preferably, the hand valve 26 is designed as a needle valve, and is arranged to be throttled until the desired working pressure has been attained.

The liquid flows from hopper 27 to a suitable tank or is returned to tank 30 which is normally charged from a liquid preparation plant (not shown in the drawing).

These tanks are equipped with level indicators, thermostats and automatic controls. Discharge from the tanks is effected by a conduit extending to the suction sides of the dosing pump, the conduit having a hand valve 31 therein.

In order to maintain and adjust the separation to an optimum degree, and to effect eflicient return of the dust through blower 34 and separator 33 to treatment chamber 11, a regulating device is arranged between the latter and separators 33, in the suction line in front of the blower, the regulating device comprising a pivotal flap valve 16 and a slide valve 161:. When the flap valve 16 is closed, the air current through the treatment chamber is throttled. The cross sectional area above the flap for the intake of fresh air increases. This cross sectional area can be so regulated by means of an additional slide valve 16a that the separators 33 perform an optimum degree of separation.

. The harmful effects of pulsation currents, occurring in the spray or treatment chamber, on the separation eddies are avoided by exhausting, from both separators, some air along with the dust and injecting it by means of a separate high pressure blower 34 and connecting line 36 tangentially into the spray chamber in the same direction as the conveying current. Each separator is exhausted by means of a separate exhaust line, and these two lines are united immediately ahead of blower intake 34. Inside the suction bends there are provided several apertures or openings 35 which are covered by rubber sleeves 37 and which are opened only when clogging is found to have occurred.

Exhaust of air from the separators is effected by a suction blower 32, and the exhaust air is delivered to a pressure filter 38 having a collecting hopper, an outlet duct 39, and a collecting bag 40.

The following examples illustrate the process of the present invention:

EXAMPLE 1 A mixture formed of 400 kg. sodium tripolyphosphate having a bulk density of 620 grams/liter and containing 60% phase-I, 50 kg. sodium silicate, 40 kg. magnesium silicate, 40 kg. carboxymethyl cellulose, 200 kg. sodium perborate and 2 kg. optical brightener was supplied continuously to a turbulent air mixer and sprayed therein, within minutes, with (l) a spray mixture formed of 168 kg. alkylaryl sulfonate (75% strength) and 46 kg. water and with (2) a spray mixture formed of nonyl phenol polyglycolether and perfume, the spray mixtures issuing through separate nozzle-rings arranged in annular fashion. A complete, fiowable detergent powder with a bulk density of 490 grams/liter was obtained. The sodium perborate could not be found to have decomposed.

EXAMPLE 2 400 kg. sodium tripolyphosphate having a bulk density of 620 grams/ liter and containing 60% phase-I were sprayed, inside a turbulent air mixer, with (1) a spray mixture formed of 168 kg. alkylaryl sulfonate (75% strength) and 46 kg. water and with 2) a spray mixture formed of 54 kg. nonylphenol glycolether and a slight proportion of perfume, the spray mixtures issuing through separate nozzle-rings arranged in annular fashion. 40 kg. sodium silicate, 50 kg. magnesium silicate, 40 kg. carboxymethyl cellulose, 200 kg. sodium perborate and 2 kg. optical brightener were added, inside an air mixer, to the sprayed product so made. A flowable final product with a bulk density of 520 grams/ liter was obtained. The sodium perborate could not be found to have decomposed.

EXAMPLE 3 A mixture formed of 400 kg. sodium tripolyphosphate having a bulk density of 630 grams/liter and containing 60% phase-I, 40 kg. magnesium silicate, 170 kg. sodium perborate and 2 kg. optical brightener was sprayed, inside a turbulent air mixer, with (l) a spray mixture formed of 166 kg. tallow oil fatty acid, 71 kg. coconut oil fatty acid and 30 kg. fatty alcohol polyglycolether, issuing through a first set of nozzles arranged in annular fashion, and with (2) a spray mixture formed of 67 kg. sodium hydroxide solution (50% strength), 55 kg. water and perfume, issuing through a second set of nozzles arranged in annular fashion. A foaming detergent composition based on soap and having a bulk density of 430 grams/liter was obtained. The perborate remained undecomposed.

EXAMPLE 4 400 kg. sodium tripolyphosphate having a bulk density of 630'grams/liter and containing phase-I was sprayed, inside a turbulent air mixer, with a spray mixture formed of 166 kg. tallow oil fatty acid, 71 kg. coconut oil fatty acid, 30 kg. fatty alcohol polyglycolether, issuing through a first set of nozzles arranged in annular fashion, and with a spray mixture formed of 67 kg. sodium hydroxide solution (50% strength), 55 kg. water and perfume, issuing through a second set of nozzles arranged in annular fashion. 40 kg. magnesium silicate, 170 kg. sodium perborate and 2 kg. optical brightener were added thereafter, inside an air mixer, to the sprayed product so made. A flowable, strongly foaming detergent composition based on soap and having a bulk density of 460 grams/liter was obtained. The sodium perborate remained undecomposed.

6 EXAMPLE 5 A mixture formed of 400 kg. sodium tripolyphosphate having a bulk density of 630 grams/liter and containing 60% phase-I, 40 kg. sodium silicate, 40 kg. magnesium silicate, 40 kg. carboxymethyl cellulose, 200 kg. sodium perborate, 2 kg. optical brightener and '90 kg. soap powder was sprayed, inside a turbulent air mixer, with (l) a spray mixture formed of 80 kg. alkylaryl sulfonate strength), 68 kg. water and a slight proportion of perfume, and with (2) 40 kg. of nonylphenol polyglycolether, the spray components issuing through separate nozzle-rings arranged in annular fashion. The detergent composition obtained as the final product had a bulk density of 480 grams/liter; it was fiowable and foamed but slightly.

EXAMPLE 6 400 kg. sodium tripolyphosphate having a bulk density of 630 grams/liter and containing 60% phase! was sprayed, inside a turbulent air mixer, with a spray mixture formed of kg. alkylaryl sulfonate (50% strength), 68 kg. water and a slight proportion of perfume, issuing through a first set of nozzles arranged in annular fashion, and with 40 kg. nonylphenol polyglycolether issuing through a second set of nozzles arranged in annular fashion. kg. soap powder, 440 kg. sodium silicate, 40 kg. magnesium silicate, 40 kg. carboxymethyl cellulose, 200 kg. sodium perborate and 2 kg. optical brightener were added thereafter, inside an air mixer, to the sprayed product so made. A flo-wable, slightly-foaming detergent composition with a bulk density of 500 grams/liter was obtained.

We claim:

1. A process for preparing pulverulent detergent compositions consisting essentially of (A) [dry pulverulent sodium tripolyphosphate containing20-100% by weight of Phase I material and having a bulk density greater than 550 grams/liter,

(B) an organic detergent or mixture thereof in liquid or pasty form, and

(C) detergent additives, in dry pulverulent form,

selected from the group consisting of silicates, optical brighteners, carboxymethyl cellulose, sodium perborate and mixtures thereof, said process comprisingspraying the (B) component, in the presence ofwater, onto the (A) component, wherein the (C) components are-dry mixed with the (A) component before, during or after the spraying step, and wherein the spraying is conducted inside a turbulent air mixer.

2. The process of claim 1 wherein the sodium tripolyphosphate consists essentially of 40 to 80% by weight phase-l material.

3. The process of claim 1, wherein the sodium tripolyphosphate has a bulk density of 600 and up to about 700 grams/liter.

4. The process of claim 1, wherein the temperature inside the turbulent air mixer is regulated by varying the temperature and quantity of the air travelling through the turbulent air mixer.

5. The process of claim 1 wherein dry pulverulent (A) and (C) components are mixed and (B) components are sprayed thereonto simultaneously.

6. The process of claim 5, wherein the mixing and spraying steps are achieved inside a turbulent air mixer which is provided with nozzles.

7. The process of claim 1 wherein the (A) and (C) components are premixed in a conventional air mixer.

8. The process of claim 1 wherein the (C) components are mixed, inside the turbulent air mixer, with the product formed by spraying (B) on (A).

9. The process of claim 1, wherein the (B) components are sprayed through a plurality of nozzles arranged in an nular fashion.

10. The process of claim 9, wherein the (B) components are sprayed through two sets of nozzles arranged in annular fashion, one above the other.

11. The process of claim 9, wherein the (B) components are sprayed through two adjacent sets of nozzles arranged in annular fashion.

12. Process of claim 1 wherein different (B) components are sprayed separately from each other.

13. The process of claim 1 wherein a slight proportion of perfume is mixed with the (B) components prior to the spraying step.

References Cited UNITED STATES PATENTS 2,308,992 1/1943 Mertens 252-97 8 FOREIGN PATENTS 3/1936 Great Britain. 11/1935 Great Britain.

5 MAYER WEINBLATT, Primary Examiner D. L. ALBRECHT, Assistant Examiner US. Cl. X.-R.

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