Note: Descriptions are shown in the official language in which they were submitted.
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A SPRAY-DRYING PROCESS
FIELD OF THE INVENTION
The present invention relates to a spray-drying process.
BACKGROUND OF THE INVENTION
Laundry detergent compositions are typically made by a process that involves
the step of
spray-drying an aqueous slurry comprising anionic detersive surfactant to form
a spray-dried
powder. Typically, this spray-drying step is the rate determining step in the
production of the
laundry detergent powder. This is especially true for low-built formulations
that have increased
drying loads. With increasing global laundry detergent powder volume demand,
many detergent
manufacturers' spray-drying towers are running at, or very near, maximum
capacity. In order to
increase the capacity of their existing spray-drying facilities, detergent
manufacturers have to
either invest in additional or upgraded spray-drying equipment and/or
formulate their spray-dried
powder with process aids that increase the formulation complexity of the spray-
dried laundry
detergent powder.
The inventors have found that by taking at least some of the anionic detersive
surfactant
from the aqueous slurry in the mixer, and adding its acid precursor at a later
stage (i.e. to the
alkaline slurry) in the spray-drying process, and by carefully controlling the
moisture level of the
alkaline slurry in the mixer, the capacity rate of the spray-drying process is
significantly
increased without the need for investment in additional spray-drying equipment
or the need for
the incorporation of process aids.
SUMMARY OF THE INVENTION
The present invention relates to a process as defined in claim 1.
DETAILED DESCRIPTION OF THE INVENTION
Spray-drying process
The process comprises the steps of: (a) forming an alkaline slurry in a mixer;
(b)
transferring the alkaline slurry from the mixer through at least one pump to a
spray pressure
nozzle; (c) contacting an acid anionic detersive surfactant precursor to the
alkaline slurry after the
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mixer and before the spray pressure nozzle to form a mixture; (d) spraying the
mixture through
the spray pressure nozzle into a spray-drying tower; (e) spray-drying the
mixture to form a spray-
dried powder; and (f) optionally, contacting an alkalinity source with the
alkaline slurry and/or
the acid anionic detersive surfactant precursor, and/or the mixture. Each of
the process steps are
described in more detail below.
Step (a)
In step (a), an alkaline slurry is formed in a mixer. The preferred mixer in
step (a) is a
crutcher mixer. The alkaline slurry in the mixer is preferably heated,
typically in the range of
50 C to 90 C. Saturated steam can be used to heat the slurry in the mixer.
Preferably, all of the
liquid components that make up the slurry are heated prior to addition to the
mixer, and the slurry
is preferably maintained at an elevated temperature in the mixer. These
temperatures are
preferably in the range of 50 C to 90 C.
Typically, the residence time of the slurry in the mixer is in the range of
from 20 seconds
to 600 seconds.
The mixer in step (a) typically has a motor size such that its installed power
is in the
range of from 50kW to 100kw.
Step (b)
In step (b), the alkaline slurry is transferred from the mixer through at
least one pump to a
spray pressure nozzle. Typically, the alkaline slurry is first transferred to
a low pressure line. The
low pressure line typically has a pressure in the range of from 4.0x105 Pa to
1.2x106 Pa.
Typically, the alkaline slurry is then pumped into a high pressure line. The
high pressure line
typically has a pressure in the range of from 4.0x106 Pa to 1.2x107 Pa.
Typically, a high pressure
pump is used to transfer the alkaline slurry from the low pressure line to the
high pressure line.
Preferably the high pressure pump is a piston pump.
Typically, the alkaline slurry passes through a second mixer during step (b).
The second
mixer is preferably a slurry disintegrator. The second mixer is typically
operated at 1,000 rpm to
3,000 rpm. This second mixer reduces the particle size of the solid material
in the slurry. The
particle size of the solid material in the slurry at the end of step (b) is
preferably less than 2.0mm.
This mitigates the risk of blocking the spray pressure nozzle.
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Ste (c)
In step (c), an acid anionic detersive surfactant precursor is contacted to
the alkaline
slurry after the mixer and before the spray pressure nozzle to form a mixture.
Preferably, the acid
anionic surfactant precursor is contacted to the alkaline slurry in a low
pressure line. However,
the acid anionic surfactant precursor may be contacted to the alkaline slurry
in a high pressure
line. Typically, the temperature of the acid anionic detersive surfactant
precursor is in the range
of from 20 C to 50 C when it is contacted with the alkaline slurry. Typically,
the ratio of the flow
rate of the alkaline slurry to the flow rate of the acid anionic detersive
surfactant precursor is
controlled. This control is typically achieved by passing the acid anionic
detersive surfactant
precursor through a mass flow meter, and monitoring the mass flow rate of the
alkaline slurry by
a loss in weight system installed on a holding tank into which the alkaline
slurry is typically
transferred prior to it being pumped into the low pressure line. The ratio of
the flow rate of the
alkaline slurry to the flow rate of the acid anionic detersive surfactant
precursor is typically in the
range of from 2.5:1 to 25:1, preferably from 5:1, or from 8:1, and preferably
to 20:1, or to 15:1.
Step (d)
In step (d), the mixture is sprayed through the spray pressure nozzle into a
spray-drying
tower. Typically, the mixture is sprayed at a pressure in the range of from
4.0x106 Pa to 1.2x107
Pa. Typically, the mixture is sprayed at a mass flow rate in the range of from
1,000kghr 1 to
70,000kghr 1. Typically, a plurality of nozzles are used in the process,
preferably the nozzles are
positioned in a circumferential manner at different heights throughout the
spray-drying tower.
The nozzles are preferably positioned in a counter-current manner with respect
to the air flow in
the tower.
Ste12 (e)
In step (e), the mixture is spray-dried to form a spray-dried powder.
Typically, the air in-
let temperature is in the range of from 200 C to 350 C. Typically, the air in-
let flow rate is in the
range of from 50,000 to 150,000kgm 3.
Optional step (f)
In optional step (f), an alkalinity source is contacted with the alkaline
slurry and/or the
acid anionic detersive surfactant precursor, and/or the mixture. The
alkalinity source is preferably
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contacted to the alkaline slurry substantially simultaneously with the acid
anionic detersive
surfactant precursor. Typically, the alkalinity is contacted to the alkaline
slurry and/or the acid
anionic detersive surfactant precursor, and/or the mixture at a temperature
above 10 C; this is
especially preferred when the alkalinity source comprises sodium hydroxide.
The alkalinity source can be contacted to the alkaline slurry and/or mixture
by injecting
the alkalinity source into the low pressure line. Alternative, the alkalinity
source, can be injected
into the high pressure line.
Typically, the ratio of the flow rate of the alkaline slurry to the flow rate
of the alkalinity
source is controlled. This control is typically achieved by passing the
alkalinity source through a
mass flow meter. The control of the mass flow rate of the alkaline slurry is
described in more
detail above.
Alkaline slurry
The alkaline slurry typically comprises: (a) from Owt% to 15wt% anionic
detersive
surfactant; and (b) from Owt% to 35wt% water. The alkaline slurry preferably
comprises from
Owt%, or from above Owt%, and preferably to 30wt%, or to 25wt%, or to 20wt%,
or to 15wt%,
or even to lOwt% water. The alkaline slurry may be substantially anhydrous.
The alkaline slurry
typically comprises one or more adjunct detergent ingredients. The alkaline
slurry preferably
comprises carbonate salt, preferably at least 5wt%, or at least lOwt%
carbonate salt. Preferably,
the alkaline slurry comprises from Owt% to lOwt%, or from above Owt%, and
preferably to
8wt%, or to 6wt%, or to wt%, or to 2wt% anionic surfactant. The alkaline
slurry may even be
essentially free of anionic detersive surfactant. By essential free of, it is
typically meant
comprises no deliberately added.
The alkaline slurry may comprise polymeric material. A preferred polymeric
material is a
carboxylate polymer. The alkaline slurry may comprise at least lwt%, or even
at least 2wt%
polymeric material.
Preferably, the weight ratio of solid inorganic material to solid organic
material present in
the slurry is in the range of from 10:1 to 10,000:1, preferably at least 35:1.
The alkaline slurry
may comprise less than lOwt% solid organic material, or less than 5wt% solid
organic material.
The alkaline slurry may even be essential free of solid organic material. For
the purpose of the
present invention, organic means any hydrocarbon component.
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Spra,-dried powder
The spray-dried powder comprises: (i) anionic detersive surfactant;
(ii) from Owt% to lOwt% zeolite builder; (iii) from Owt% to lOwt% phosphate
builder; and (iv)
optionally from Owt% to 15wt% silicate salt. The spray-dried powder typically
comprises
additional adjunct detergent ingredients. Preferably, the spray-dried powder
comprises a
carbonate salt.
The spray-dried powder typically has a particle size distribution such that
the weight
average particle size is in the range of from 300 micrometers to 600
micrometers, and preferably
less than 1Owt% of the spray-dried powder has a particle size greater than
1,180 micrometers,
and preferably less than lOwt% of the spray-dried powder has a particle size
of less than 150
micrometers.
Typically, the spray-dried powder has a bulk density in the range of from
100g/l to 700g/l.
The spray-dried powder typically has a moisture content of less than 5wt%,
preferably less than
4wt%, or even less than 3wt%. Preferably, the spray-dried powder is white.
Acid anionic detersive surfactant precursor
The acid anionic detersive surfactant precursor preferably comprises C8-C24
alkyl benzene
sulphonic acid. However, any acid anionic detersive surfactant precursor may
be used in the
present invention.
Anionic detersive surfactant
The anionic detersive surfactant preferably comprises alkyl benzene
sulphonate.
Preferably the anionic detersive surfactant comprises at least 50%, preferably
at least 55%, or at
least 60%, or at least 65%, or at least 70%, or even at least 75%, by weight
of the anionic
detersive surfactant, of alkyl benzene sulphonate. Preferably the alkyl
benzene sulphonate is a
5 linear or branched, substituted or unsubstituted, C8_18 alkyl benzene
sulphonate. This is the
optimal level of the C8_18 alkyl benzene sulphonate to provide a good cleaning
performance. The
C8_18 alkyl benzene sulphonate can be a modified alkylbenzene sulphonate
(MLAS) as described
in more detail in WO 99/05243, WO 99/05242, WO 99/05244, WO 99/05082, WO
99/05084,
WO 99/05241, WO 99/07656, WO 00/23549, and WO 00/23548. Highly preferred C8_18
alkyl
benzene sulphonates are linear CIO-13 alkylbenzene sulphonates. Especially
preferred are linear
Clo-13 alkylbenzene sulphonates that are obtainable, preferably obtained, by
sulphonating
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commercially available linear alkyl benzenes (LAB); suitable LAB include low 2-
phenyl LAB,
such as those supplied by Sasol under the tradename Isochem or those supplied
by Petresa
under the tradename Petrelab , other suitable LAB include high 2-phenyl LAB,
such as those
supplied by Sasol under the tradename Hyblene .
The anionic detersive surfactant may preferably comprise other anionic
detersive
surfactants. A preferred adjunct anionic detersive surfactant is a non-
alkoxylated anionic
detersive surfactant. The non-alkoxylated anionic detersive surfactant can be
an alkyl sulphate,
an alkyl phosphate, an alkyl phosphonate, an alkyl carboxylate or any mixture
thereof. The non-
alkoxylated anionic surfactant can be selected from the group consisting of;
C10-C20 primary,
branched-chain, linear-chain and random-chain alkyl sulphates (AS), typically
having the
following formula:
CH3(CH2)XCH2-OSO3- M+
wherein, M is hydrogen or a cation which provides charge neutrality, preferred
cations are
sodium and ammonium cations, wherein x is an integer of at least 7, preferably
at least 9; C10-C18
secondary (2,3) alkyl sulphates, typically having the following formulae:
OSO3 M+ OSO3 M+
CH3(CH2)X(CH)CH3 or CH3(CH2)y(CH)CH2CH3
wherein, M is hydrogen or a cation which provides charge neutrality, preferred
cations include
sodium and ammonium cations, wherein x is an integer of at least 7, preferably
at least 9, y is an
integer of at least 8, preferably at least 9; C10-C18 alkyl carboxylates; mid-
chain branched alkyl
sulphates as described in more detail in US 6,020,303 and US 6,060,443; methyl
ester sulphonate
(MES); alpha-olefin sulphonate (AOS); and mixtures thereof.
Another preferred anionic detersive surfactant is an alkoxylated anionic
detersive
surfactant. The presence of an alkoxylated anionic detersive surfactant in the
spray-dried powder
provides good greasy soil cleaning performance, gives a good sudsing profile,
and improves the
hardness tolerance of the anionic detersive surfactant system. It may be
preferred for the anionic
detersive surfactant to comprise from 1% to 50%, or from 5%, or from 10%, or
from 15%, or
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from 20%, and to 45%, or to 40%, or to 35%, or to 30%, by weight of the
anionic detersive
surfactant system, of an alkoxylated anionic detersive surfactant.
Preferably, the alkoxylated anionic detersive surfactant is a linear or
branched, substituted
or unsubstituted C12_18 alkyl alkoxylated sulphate having an average degree of
alkoxylation of
from 1 to 30, preferably from 1 to 10. Preferably, the alkoxylated anionic
detersive surfactant is a
linear or branched, substituted or unsubstituted C12-18 alkyl ethoxylated
sulphate having an
average degree of ethoxylation of from 1 to 10. Most preferably, the
alkoxylated anionic
detersive surfactant is a linear unsubstituted C12-18 alkyl ethoxylated
sulphate having an average
degree of ethoxylation of from 3 to 7.
The alkoxylated anionic detersive surfactant, when present with an alkyl
benzene
sulphonate may also increase the activity of the alkyl benzene sulphonate by
making the alkyl
benzene sulphonate less likely to precipitate out of solution in the presence
of free calcium
cations. Preferably, the weight ratio of the alkyl benzene sulphonate to the
alkoxylated anionic
detersive surfactant is in the range of from 1:1 to less than 5:1, or to less
than 3:1, or to less than
1.7:1, or even less than 1.5:1. This ratio gives optimal whiteness maintenance
performance
combined with a good hardness tolerance profile and a good sudsing profile.
However, it may be
preferred that the weight ratio of the alkyl benzene sulphonate to the
alkoxylated anionic
detersive surfactant is greater than 5:1, or greater than 6:1, or greater than
7:1, or even greater
than 10:1. This ratio gives optimal greasy soil cleaning performance combined
with a good
hardness tolerance profile, and a good sudsing profile.
Suitable alkoxylated anionic detersive surfactants are: Texapan LEST by
Cognis;
Cosmacol AESTm by Sasol; BES151Tm by Stephan; Empicol ESC70/UTm; and mixtures
thereof.
Preferably, the anionic detersive surfactant comprises from 0% to 10%,
preferably to 8%,
or to 6%, or to 4%, or to 2%, or even to 1%, by weight of the anionic
detersive surfactant, of
unsaturated anionic detersive surfactants such as alpha-olefin sulphonate.
Preferably the anionic
detersive surfactant is essentially free of unsaturated anionic detersive
surfactants such as alpha-
olefin sulphonate. By "essentially free of' it is typically meant "comprises
no deliberately
added". Without wishing to be bound by theory, it is believed that these
levels of unsaturated
anionic detersive surfactants such as alpha-olefin sulphonate ensure that the
anionic detersive
surfactant is bleach compatible.
Preferably, the anionic detersive surfactant comprises from 0% to 10%,
preferably to 8%,
or to 6%, or to 4%, or to 2%, or even to 1%, by weight of alkyl sulphate.
Preferably the anionic
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detersive surfactant is essentially free of alkyl sulphate. Without wishing to
be bound by theory,
it is believed that these levels of alkyl sulphate ensure that the anionic
detersive surfactant is
hardness tolerant.
Zeolite builder
The spray-dried powder typically comprises from 0% to lOwt% zeolite builder,
preferably
to 9wt%, or to 8wt%, or to 7wt%,or to 6wt%, or to 5wt%, or to 4wt%, or to
3wt%, or to 2wt%,
or to lwt%, or to less than 1% by weight of the spray-dried powder, of zeolite
builder. It may
even be preferred for the spray-dried powder to be essentially free from
zeolite builder. By
essentially free from zeolite builder it is typically meant that the spray-
dried powder comprises
no deliberately added zeolite builder. This is especially preferred if it is
desirable for the spray-
dried powder to be very highly soluble, to minimise the amount of water-
insoluble residues (for
example, which may deposit on fabric surfaces), and also when it is highly
desirable to have
transparent wash liquor. Zeolite builders include zeolite A, zeolite X,
zeolite P and zeolite MAP.
Phosphate builder
The spray-dried powder typically comprises from 0% to lOwt% phosphate builder,
preferably to 9wt%, or to 8wt%, or to 7wt%,or to 6wt%, or to 5wt%, or to 4wt%,
or to 3wt%, or
to 2wt%, or to lwt%, or to less than 1% by weight of the spray-dried powder,
of phosphate
builder. It may even be preferred for the spray-dried powder to be essentially
free from phosphate
builder. By essentially free from phosphate builder it is typically meant that
the spray-dried
powder comprises no deliberately added phosphate builder. This is especially
preferred if it is
desirable for the composition to have a very good environmental profile.
Phosphate builders
include sodium tripolyphosphate.
Silicate salt
The spray-dried powder optionally comprises from 0% to 20wt% silicate salt,
preferably
from lwt%, or from 2wt%, or from 3wt%, and preferably to 15wt%, or tolOwt%, or
even to 5%
silicate salt. Silicate salts include amorphous silicates and crystalline
layered silicates (e.g. SKS-
6). A preferred silicate salt is sodium silicate.
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Carbonate salt
The spray-dried powder typically comprises carbonate salt, typically from 1%
to 50%, or
from 5% to 25% or from 10% to 20%, by weight of the spray-dried powder, of
carbonate salt. A
preferred carbonate salt is sodium carbonate and/or sodium bicarbonate. A
highly preferred
carbonate salt is sodium carbonate. Preferably, the spray-dried powder may
comprise from 10%
to 40%, by weight of the spray-dried powder, of sodium carbonate. However, it
may also be
preferred for the spray-dried powder to comprise from 2% to 8%, by weight of
the spray-dried
powder, of sodium bicarbonate. Sodium bicarbonate at these levels provides
good alkalinity
whilst minimizing the risk of surfactant gelling which may occur in surfactant-
carbonate systems.
If the spray-dried powder comprises sodium carbonate and zeolite, then
preferably the weight
ratio of sodium carbonate to zeolite is at least 15:1.
High levels of carbonate improve the cleaning performance of the composition
by
increasing the pH of the wash liquor. This increased alkalinity: improves the
performance of the
bleach, if present; increases the tendency of soils to hydrolyse, which
facilitates their removal
from the fabric; and also increases the rate, and degree, of ionization of the
soils to be cleaned
(n.b. ionized soils are more soluble and easier to remove from the fabrics
during the washing
stage of the laundering process). In addition, high carbonate levels improve
the flowability of the
spray-dried powder.
Alkalinity source
The alkalinity source preferably comprises sodium hydroxide. The alkalinity
source
preferably comprises carbonate salt. The alkalinity source preferably
comprises silicate salt.
Adjunct detergent ingredients
Suitable adjunct ingredients include: detersive surfactants such as anionic
detersive
surfactants, nonionic detersive surfactants, cationic detersive surfactants,
zwitterionic detersive
surfactants, amphoteric detersive surfactants; preferred nonionic detersive
surfactants are C8.18
alkyl alkoxylated alcohols having an average degree of alkoxylation of from 1
to 20, preferably
from 3 to 10, most preferred are C12_18 alkyl ethoxylated alcohols having an
average degree of
alkoxylation of from 3 to 10; preferred cationic detersive surfactants are
mono-C6_18 alkyl mono-
hydroxyethyl di-methyl quaternary ammonium chlorides, more preferred are mono-
C8_lo alkyl
mono-hydroxyethyl di-methyl quaternary ammonium chloride, mono-C10-12 alkyl
mono-
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hydroxyethyl di-methyl quaternary ammonium chloride and mono-C10 alkyl mono-
hydroxyethyl
di-methyl quaternary ammonium chloride; source of peroxygen such as
percarbonate salts and/or
perborate salts, preferred is sodium percarbonate, the source of peroxygen is
preferably at least
partially coated, preferably completely coated, by a coating ingredient such
as a carbonate salt, a
5 sulphate salt, a silicate salt, borosilicate, or mixtures, including mixed
salts, thereof; bleach
activator such as tetraacetyl ethylene diamine, oxybenzene sulphonate bleach
activators such as
nonanoyl oxybenzene sulphonate, caprolactam bleach activators, imide bleach
activators such as
N-nonanoyl-N-methyl acetamide, preformed peracids such as N,N-pthaloylamino
peroxycaproic
acid, nonylamido peroxyadipic acid or dibenzoyl peroxide; enzymes such as
amylases,
10 carbohydrases, cellulases, laccases, lipases, oxidases, peroxidases,
proteases, pectate lyases and
mannanases; suds suppressing systems such as silicone based suds suppressors;
fluorescent
whitening agents; photobleach; filler salts such as sulphate salts, preferably
sodium sulphate;
fabric-softening agents such as clay, silicone and/or quaternary ammonium
compounds;
flocculants such as polyethylene oxide; dye transfer inhibitors such as
polyvinylpyrrolidone, poly
4-vinylpyridine N-oxide and/or co-polymer of vinylpyrrolidone and
vinylimidazole; fabric
integrity components such as hydrophobically modified cellulose and oligomers
produced by the
condensation of imidazole and epichlorhydrin; soil dispersants and soil anti-
redeposition aids
such as alkoxylated polyamines and ethoxylated ethyleneimine polymers; anti-
redeposition
components such as carboxymethyl cellulose and polyesters; perfumes; sulphamic
acid or salts
thereof; citric acid or salts thereof; and dyes such as orange dye, blue dye,
green dye, purple dye,
pink dye, or any mixture thereof.
EXAMPLES
While particular embodiments of the present invention have been illustrated
and described, it
would be obvious to those skilled in the art that various other changes and
modifications can be
made without departing from the spirit and scope of the invention. It is
therefore intended to
cover in the appended claims all such changes and modifications that are
within the scope of this
invention.
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Example 1. A spray-dried laundry detergent powder and process of making it.
Aqueous alkaline slurry coMposition.
Component Aqueous slurry (parts)
Sodium Silicate 8.5
Acrylate/maleate copolymer 3.2
Hydroxyethane di(methylene phosphonic acid) 0.6
Sodium carbonate 8.8
Sodium sulphate 42.9
Water 19.7
Miscellaneous, such as magnesium sulphate, and one or more 1.7
stabilizers
Aqueous alkaline slurry parts 85.4
Preparation of a spray-dried laundry detergent powder.
An alkaline aqueous slurry having the composition as described above is
prepared in a slurry
making vessel (crutcher). The moisture content of the above slurry is 23.1 %.
Any ingredient
added above in liquid form is heated to 70 C, such that the aqueous slurry is
never at a
temperature below 70 C. Saturated steam at a pressure of 6.0x105 Pa is
injected into the crutcher
to raise the temperature to 90 C. The slurry is then pumped into a low
pressure line (having a
pressure of 5.0x105 Pa).
Separately, 11.4 parts of C8-C24 alkyl benzene sulphonic acid (HLAS), and 3.2
parts of a
50w/w% aqueous sodium hydroxide solution are pumped into the low pressure
line. The mixture
is then pumped by a high pressure pump into a high pressure line (having an
exit pressure of
8.0x106 Pa). The mixture is then sprayed at a rate of 1,640kg/hour at a
pressure of 8.0x106 Pa and
at a temperature of 90 C +/-2 C through a spray pressure nozzle into a counter
current spray-
drying tower with an air inlet temperature of 300 C. The mixture is atomised
and the atomised
slurry is dried to produce a solid mixture, which is then cooled and sieved to
remove oversize
material (>1.8mm) to form a spray-dried powder, which is free-flowing. Fine
material
(<0.15mm) is elutriated with the exhaust the exhaust air in the spray-drying
tower and collected
in a post tower containment system. The spray-dried powder has a moisture
content of 2.5wt%, a
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bulk density of 510 g/l and a particle size distribution such that greater
than 80wt% of the spray-
dried powder has a particle size of from 150 to 710 micrometers. The
composition of the spray-
dried powder is given below.
Spray-dried laundry detergent powder composition
Component %w/w Spray Dried Powder
Sodium silicate salt 10.0
C8-C24 alkyl benzene sulphonate 15.1
Acrylate/maleate copolymer 4.0
Hydroxyethane di(methylene phosphonic acid) 0.7
Sodium carbonate 11.9
Sodium sulphate 53.7
Water 2.5
Miscellaneous, such as magnesium sulphate, and 2.1
one or more stabilizers
Total Parts 100.00
A granular laundry detergent composition.
Component %w/w granular
laundry detergent
composition
Spray-dried powder of example 1 (described above) 59.38
91.6wt% active linear alkyl benzene sulphonate flake supplied 0.22
by Stepan under the tradename Nacconol 90G
Citric acid 5.00
Sodium percarbonate (having from 12% to 15% active AvOx) 14.70
Photobleach particle 0.01
Lipase (11.00mg active/g) 0.70
Amylase (21.55mg active/g) 0.33
Protease (56.00mg active/g) 0.43
Tetraacetyl ethylene diamine agglomerate (92wt% active) 4.35
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Suds suppressor agglomerate (1 1.5wt% active) 0.87
Acrylate/maleate copolymer particle (95.7wt% active) 0.29
Green/Blue carbonate speckle 0.50
Sodium Sulphate 9.59
Solid perfume particle 0.63
Ethoxylated C12-C18 alcohol having an average degree of 3.00
ethoxylation of 7 (AE7)
Total Parts 100.00
The above laundry detergent composition was prepared by dry-mixing all of the
above particles
(all except the AE7) in a standard batch mixer. The AE7 in liquid form is
sprayed on the particles
in the standard batch mixer. Alternatively, the AE7 in liquid form is sprayed
onto the spray-dried
powder of example 1. The resultant powder is then mixed with all of the other
particles in a
standard batch mixer.
The dimensions and values disclosed herein are not to be understood as being
strictly limited to
the exact numerical values recited. Instead, unless otherwise specified, each
such dimension is
intended to mean both the recited value and a functionally equivalent range
surrounding that
value. For example, a dimension disclosed as "40 mm" is intended to mean
"about 40 mm".
