U.S. patent application number 10/532791 was filed with the patent office on 2006-10-26 for solidification and hardening accelerator for hydraulic binding agents and method for the production thereof.
This patent application is currently assigned to SIKA TECHNOLOGY AG. Invention is credited to Benedikt Lindlar, Urs Mader, Marcel Sommer, Franz Wombacher.
Application Number | 20060236895 10/532791 |
Document ID | / |
Family ID | 32187168 |
Filed Date | 2006-10-26 |
United States Patent
Application |
20060236895 |
Kind Code |
A1 |
Sommer; Marcel ; et
al. |
October 26, 2006 |
Solidification and hardening accelerator for hydraulic binding
agents and method for the production thereof
Abstract
A setting and curing accelerator for hydraulic binders
comprises: Al.sub.2(SO.sub.4).sub.3 aluminum sulfate, Al(OH).sub.3
aluminum hydroxide and mineral acid in aqueous solution. The
setting and curing accelerator preferably comprises: 10-50% of
Al.sub.2(SO.sub.4).sub.3 aluminum sulfate, 5-30% of Al(OH).sub.3
aluminum hydroxide, 0.5-10% of a mineral acid in aqueous
solution.
Inventors: |
Sommer; Marcel; (Pfungen,
CH) ; Mader; Urs; (Frauenfeld, CH) ;
Wombacher; Franz; (Oberlunkhofen, CH) ; Lindlar;
Benedikt; (Konstanz, DE) |
Correspondence
Address: |
OLIFF & BERRIDGE, PLC
P.O. BOX 19928
ALEXANDRIA
VA
22320
US
|
Assignee: |
SIKA TECHNOLOGY AG
Zugerstrasse 50
Baar
CH
CH-6340
|
Family ID: |
32187168 |
Appl. No.: |
10/532791 |
Filed: |
November 11, 2003 |
PCT Filed: |
November 11, 2003 |
PCT NO: |
PCT/EP03/12579 |
371 Date: |
June 14, 2006 |
Current U.S.
Class: |
106/815 ;
106/808; 106/819 |
Current CPC
Class: |
Y02E 60/32 20130101;
C04B 2103/10 20130101; C04B 28/02 20130101; C04B 2111/00155
20130101; C04B 40/0039 20130101; C04B 28/02 20130101; C04B 2103/10
20130101; C04B 40/0039 20130101; C04B 14/303 20130101; C04B 22/082
20130101; C04B 22/148 20130101; C04B 40/0039 20130101; C04B 14/303
20130101; C04B 22/148 20130101; C04B 22/165 20130101; C04B 40/0039
20130101; C04B 14/303 20130101; C04B 22/0013 20130101; C04B 22/148
20130101; C04B 40/0039 20130101; C04B 14/062 20130101; C04B 14/303
20130101; C04B 22/082 20130101; C04B 22/148 20130101; C04B 24/122
20130101; C04B 24/2641 20130101 |
Class at
Publication: |
106/815 ;
106/808; 106/819 |
International
Class: |
C04B 28/26 20060101
C04B028/26; C04B 7/00 20060101 C04B007/00; C04B 40/00 20060101
C04B040/00 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 19, 2002 |
EP |
02025871.1 |
Claims
1. A setting and curing accelerator for hydraulic binders,
comprising: Al.sub.2(SO.sub.4).sub.3 aluminum sulfate, Al(OH).sub.3
aluminum hydroxide and mineral acid in aqueous solution.
2. The setting and curing accelerator as claimed in claim 1,
characterized in that (in % by weight) the proportion of aluminum
sulfate is 10-50% and/or the proportion of aluminum hydroxide is
5-30% and/or the proportion of mineral acid is 0.5-10%.
3. The setting and curing accelerator as claimed in claim 1,
characterized in that (in % by weight) the proportion of aluminum
sulfate is 30-50% and/or the proportion of aluminum hydroxide is
5-20%.
4. The setting and curing accelerator as claimed in claim 1,
characterized in that (in % by weight) the proportion of aluminum
sulfate is 40-45% and/or the proportion of aluminum hydroxide is
10-17% and/or the proportion of mineral acid is 0.5-8%.
5. The setting and curing accelerator as claimed in claim 1,
characterized in that the mineral acid present comprises (in % by
weight) 1-5% of H.sub.3PO.sub.4 phosphoric acid and/or 0.5-3.0% of
H.sub.3BO.sub.3 boric acid.
6. The setting and curing accelerator as claimed in claim 1,
characterized in that (in % by weight) 0-10% of alkanolamine and/or
0-5.0% of fluidizer and/or 0-20% of stabilizer are present.
7. The setting and curing accelerator as claimed in claim 1,
characterized in that (in % by weight) 0-5% of alkanolamine and/or
0-10% of stabilizer and/or 0-3.0% of fluidizer are present.
8. The setting and curing accelerator as claimed in claim 6,
characterized in that the alkanolamine is a diethanolamine.
9. The setting and curing accelerator as claimed in claim 6,
characterized in that the stabilizer is a silica sol.
10. The setting and curing accelerator as claimed in claim 6,
characterized in that the fluidizer is a polycarboxylate.
11. A process for producing a setting and curing accelerator,
characterized in that a setting and curing accelerator as claimed
in claim 1 which is present in aqueous solution is dried, in
particular by a spray drying process.
12. The process for producing a setting and curing accelerator as
claimed in claim 11, characterized in that the dried mixture
obtained is dissolved in water before addition to the hydraulic
binder.
13. A process for producing a setting and curing accelerator as
claimed in any of claim 1, characterized in that in the production
of the aqueous solution and the addition of the components in the
production of the solution, the solution is heated in a range from
room temperature to 90.degree. C.
14. The process for producing a setting and curing accelerator as
claimed in claim 13, characterized in that the solution is heated
to 50-80.degree. C.
15. A method of accelerating the setting and curing of hydraulic
binders and also mortar or concrete produced therefrom,
characterized in that a setting and curing accelerator as claimed
in claim 1 is added in an amount of from 0.1 to 10% by weight to a
mixture comprising hydraulic binders, with the percentages by
weight being based on the weight of the hydraulic binder.
16. The use of the setting and curing accelerator as claimed in
claim 1 in a spray concrete or spray mortar.
Description
TECHNICAL FIELD
[0001] The invention relates to a setting and curing accelerator
for hydraulic binders according to the preamble of the first
claim.
[0002] The invention likewise relates to a process for producing a
setting and curing accelerator for hydraulic binders according to
the preamble of the independent process claim.
PRIOR ART
[0003] Many substances which accelerate the setting and curing of
concrete are known. Customary substances are, for example, strongly
alkaline substances such as alkali metal hydroxides, alkali metal
carbonates, alkali metal silicates, alkali metal aluminates and
alkaline earth metal chlorides. However, the strongly alkaline
substances have undesirable effects on the processor, e.g. burns,
and they reduce the final strength and durability of the
concrete.
[0004] EP 0 076 927 B1 discloses alkali-free setting accelerators
for hydraulic binders which are said to avoid these disadvantages.
To accelerate the setting and curing of a hydraulic binder such as
cement, lime, hydraulic lime and plaster of Paris and mortar and
concrete produced therefrom, from 0.5 to 10% by weight, based on
the weight of this binder, of an alkali-free setting and curing
accelerator comprising aluminum hydroxide is added to the mixture
comprising the binder mentioned.
[0005] Such mortars and concretes are particularly well-suited as
spray mortar and concrete as a result of the accelerated setting
and curing.
[0006] EP 0 946 451 B1 discloses setting and curing accelerators in
dissolved form for hydraulic binders, which can be more easily
mixed into the concrete when spraying the concrete. Such a setting
and curing accelerator comprises, inter alia, aluminum hydroxide,
aluminum salts and organic carboxylic acids. However, a
disadvantage of such setting and curing accelerators is the
stability of the solution.
SUMMARY OF THE INVENTION
[0007] It is an object of the invention to achieve a very high
accelerating action combined with a very long life of the
accelerator for a setting and curing accelerator for hydraulic
binders of the type mentioned at the outset.
[0008] According to the invention, this is achieved by the features
of the first claim.
[0009] The advantages of the invention are, inter alia, that a high
stability, i.e. stabilization of the accelerator solution, is
achieved by means of the accelerators of the invention and that
high acceleration of the setting and curing of hydraulic binders is
achieved.
[0010] Hydraulic binders with addition of the accelerator of the
invention can be processed advantageously by spraying because of
their accelerated setting and curing behavior.
[0011] Further advantageous embodiments of the invention are
disclosed in the subordinate claims.
WAY OF CARRYING OUT THE INVENTION
[0012] A setting and curing accelerator according to the invention
for hydraulic binders comprises:
[0013] Al.sub.2(SO.sub.4).sub.3 aluminum sulfate, Al(OH).sub.3
aluminum hydroxide and mineral acid in aqueous solution.
[0014] Such a setting and curing accelerator according to the
invention advantageously consists essentially of (in % by
weight):
[0015] 10-50% of Al.sub.2(SO.sub.4).sub.3 aluminum sulfate,
[0016] 5-30% of Al(OH).sub.3 aluminum hydroxide,
[0017] 0.5-10% of mineral acid,
[0018] 0-10% of alkanolamine,
[0019] 0-5.0% of fluidizer,
[0020] 0-20% of stabilizer,
in aqueous solution.
[0021] As mineral acid, preference is given to using phosphoric or
boric acid, but it is also possible to use other mineral acids
having a similar action, e.g. nitric acid, sulfuric acid, etc.
[0022] Diethanolamine is advantageously used as alkanolamine.
Polycarboxylates, particularly advantageously Sika ViscoCrete.RTM.,
in particular Sika ViscoCrete.RTM. 20HE are advantageously used as
fluidizers.
[0023] Silica sol is advantageously used as stabilizer.
[0024] Particularly advantageous setting and curing accelerators
consist essentially of (in % by weight):
[0025] 30-50% of Al.sub.2(SO.sub.4).sub.3 aluminum sulfate, in
particular 40-45%, and/or
[0026] 5-20% of Al(OH).sub.3 aluminum hydroxide, in particular
10-17%, and/or
[0027] 0.5-8% of mineral acid and/or
[0028] 0-5% of alkanolamine and/or
[0029] 0.1-3.0% of fluidizer, in particular from 0.1 to 1.0%,
and/or
[0030] 0-10% of stabilizer.
[0031] It is also advantageous to add the mineral acid fraction of
0.5-10% as H.sub.3PO.sub.4 phosphoric acid and/or H.sub.3BO.sub.3
boric acid. Particularly advantageous ranges are 1-5% of
H.sub.3PO.sub.4 phosphoric acid and/or 0.5-3.0% of H.sub.3BO.sub.3
boric acid.
[0032] A number of samples of an accelerator according to the
invention were produced in the above-described ranges. The
composition of these samples is indicated in the following
examples.
EXAMPLE 1
[0033] 7.60 kg of aluminum hydroxide Al(OH).sub.3 are added to a
solution of 22.50 kg of aluminum sulfate with water of
crystallization Al.sub.2(SO.sub.4).sub.3.times.14H.sub.2O in 17.06
kg of water H.sub.2O at 70-80.degree. C. 1.14 kg of a phosphoric
acid solution H.sub.3PO.sub.4 (75%), 2 kg of a silica sol (10%
solids content) and 1.70 kg of a corrosion inhibitor, viz. a 90%
solution of diethanolamine, are subsequently added to the resulting
solution and this mixture is stirred for half an hour.
[0034] The stability of this mixture was at least 70 days.
EXAMPLE 2
[0035] 7.60 kg of aluminum hydroxide Al (OH).sub.3 are added to a
solution of 22.50 kg of aluminum sulfate with water of
crystallization Al.sub.2(SO.sub.4).sub.3.times.14H.sub.2O in 14.86
kg of water H.sub.2O at 70-80.degree. C. 2.84 kg of a phosphoric
acid solution H.sub.3PO.sub.4 (75%), 0.50 kg of polycarboxylates,
e.g. Sika ViscoCrete.RTM. 20HE which is a high-performance
fluidizer, and 1.70 kg of a corrosion inhibitor, viz. a 90%
solution of diethanolamine, are subsequently added to the solution
obtained and this mixture is stirred for half an hour.
[0036] The stability of this mixture was at least 70 days.
EXAMPLE 3
[0037] 8.00 kg of aluminum hydroxide Al(OH).sub.3 are added to a
solution of 22.50 kg of aluminum sulfate with water of
crystallization Al.sub.2(SO.sub.4).sub.3.times.14H.sub.2O in 16.56
kg of water H.sub.2O at 70-80.degree. C. 1.14 kg of a phosphoric
acid solution H.sub.3PO.sub.4 (75%), 0.10 kg of boric acid
H.sub.3BO.sub.3 and 1.70 kg of a corrosion inhibitor, viz. a 90%
solution of diethanolamine, are subsequently added to the solution
obtained and this mixture is stirred for half an hour. The
stability of this mixture was at least 70 days.
EXAMPLE 4
[0038] 8.10 kg of aluminum hydroxide Al(OH).sub.3 are added to a
solution of 20.60 kg of aluminum sulfate with water of
crystallization Al.sub.2(SO.sub.4).sub.3.times.14H.sub.2O in 21.00
kg of water H.sub.2O at 70-80.degree. C. 0.30 kg of boric acid
H.sub.3BO.sub.3 is subsequently added to the resulting solution and
this mixture is stirred for half an hour.
[0039] The stability of this mixture was at least 70 days.
EXAMPLE 5
[0040] 8.00 kg of aluminum hydroxide Al(OH).sub.3 are added to a
solution of 21.00 kg of aluminum sulfate with water of
crystallization Al.sub.2(SO.sub.4).sub.3.times.14H.sub.2O in 20.00
kg of water H.sub.2O at 70-80.degree. C. 1.00 kg of boric acid
H.sub.3BO.sub.3 and 0.50 kg of polycarboxylates, e.g. Sika
ViscoCrete.RTM. 20HE which is a high-performance fluidizer, are
subsequently added to the solution obtained and this mixture is
stirred for half an hour.
[0041] The stability of this mixture was at least 70 days.
[0042] From 0.1 to 10% by weight of the accelerator of the
invention can be added to the hydraulic binder.
[0043] To determine the effectiveness of the accelerator of the
invention from Examples 1 to 5, 6% of the accelerator from the
above examples was in each case mixed into portland cement and
penetrometer values were determined. The following table shows the
penetrometer values together with the time required in each case to
reach strengths of 200 g, 600 g and 2200 g. These penetrometer
values were determined using a needle having a diameter of 3 mm and
a test apparatus from RMU.
[0044] A sample of portland cement without accelerator was used as
comparison and the penetrometer values for the same sample
composition when the accelerator was left out without replacement
and when the accelerator was replaced by a corresponding amount of
water were determined. TABLE-US-00001 Penetrometer value for 200 g
600 g 2200 g Example 1 5 min 7 min 15 min Example 2 6 min 8 min 16
min Example 3 6 min 9 min 20 min Example 4 7 min 14 min 40 min
Example 5 12 min 20 min 55 min Sample without accelerator 450 min
485 min 540 min Sample without accelerator 490 min 522 min 579 min
but with equivalent amount of water
[0045] The accelerators prepared as described in Examples 1 to 5
thus gave solutions which display satisfactory acceleration values
and remain stable for a sufficiently long time.
[0046] The accelerators of the invention can also be used for
hydraulic binders other than cement, e.g. blended cements, lime,
hydraulic lime and plaster of Paris and also mortar and concrete
produced therefrom.
[0047] Of course, the invention is not restricted to the example
presented and described. The accelerators present in aqueous
solution can also be used in dried form, e.g. after drying by means
of a generally known spray drying process. The dried powder
obtained in this way, which is readily soluble in water, is
dissolved in water before use and then used in the same way as the
liquid accelerator. The samples prepared as described in Examples 1
to 5 can also be produced in a temperature range from room
temperature RT to 90.degree. C., but preferably in a range from 50
to 80.degree. C.
* * * * *