AU2013273765A1 - A Stabilising Composition - Google Patents
A Stabilising Composition Download PDFInfo
- Publication number
- AU2013273765A1 AU2013273765A1 AU2013273765A AU2013273765A AU2013273765A1 AU 2013273765 A1 AU2013273765 A1 AU 2013273765A1 AU 2013273765 A AU2013273765 A AU 2013273765A AU 2013273765 A AU2013273765 A AU 2013273765A AU 2013273765 A1 AU2013273765 A1 AU 2013273765A1
- Authority
- AU
- Australia
- Prior art keywords
- composition
- weight
- magnesium
- sulphate
- stabilising composition
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
- 239000000203 mixture Substances 0.000 title claims abstract description 233
- 230000003019 stabilising effect Effects 0.000 title claims abstract description 46
- CSNNHWWHGAXBCP-UHFFFAOYSA-L Magnesium sulfate Chemical compound [Mg+2].[O-][S+2]([O-])([O-])[O-] CSNNHWWHGAXBCP-UHFFFAOYSA-L 0.000 claims abstract description 142
- TWRXJAOTZQYOKJ-UHFFFAOYSA-L Magnesium chloride Chemical compound [Mg+2].[Cl-].[Cl-] TWRXJAOTZQYOKJ-UHFFFAOYSA-L 0.000 claims abstract description 137
- 229910052943 magnesium sulfate Inorganic materials 0.000 claims abstract description 75
- 229910001629 magnesium chloride Inorganic materials 0.000 claims abstract description 73
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 claims abstract description 72
- 239000000395 magnesium oxide Substances 0.000 claims abstract description 69
- 235000019341 magnesium sulphate Nutrition 0.000 claims abstract description 66
- AXZKOIWUVFPNLO-UHFFFAOYSA-N magnesium;oxygen(2-) Chemical compound [O-2].[Mg+2] AXZKOIWUVFPNLO-UHFFFAOYSA-N 0.000 claims abstract description 66
- OSGAYBCDTDRGGQ-UHFFFAOYSA-L calcium sulfate Chemical compound [Ca+2].[O-]S([O-])(=O)=O OSGAYBCDTDRGGQ-UHFFFAOYSA-L 0.000 claims abstract description 38
- 239000001175 calcium sulphate Substances 0.000 claims abstract description 15
- 235000011132 calcium sulphate Nutrition 0.000 claims abstract description 15
- BPQQTUXANYXVAA-UHFFFAOYSA-N Orthosilicate Chemical compound [O-][Si]([O-])([O-])[O-] BPQQTUXANYXVAA-UHFFFAOYSA-N 0.000 claims abstract description 14
- 239000000654 additive Substances 0.000 claims abstract description 13
- BLRPTPMANUNPDV-UHFFFAOYSA-N Silane Chemical compound [SiH4] BLRPTPMANUNPDV-UHFFFAOYSA-N 0.000 claims abstract description 12
- 229910000077 silane Inorganic materials 0.000 claims abstract description 12
- 230000000996 additive effect Effects 0.000 claims abstract description 7
- 239000002689 soil Substances 0.000 claims description 64
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 47
- 239000000463 material Substances 0.000 claims description 34
- 238000000034 method Methods 0.000 claims description 32
- 239000000428 dust Substances 0.000 claims description 23
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 claims description 16
- 239000000758 substrate Substances 0.000 claims description 16
- 238000010276 construction Methods 0.000 claims description 15
- 230000006641 stabilisation Effects 0.000 claims description 15
- VEXZGXHMUGYJMC-UHFFFAOYSA-M Chloride anion Chemical compound [Cl-] VEXZGXHMUGYJMC-UHFFFAOYSA-M 0.000 claims description 12
- 239000011507 gypsum plaster Substances 0.000 claims description 11
- 239000000843 powder Substances 0.000 claims description 11
- 239000010426 asphalt Substances 0.000 claims description 9
- ZOMBKNNSYQHRCA-UHFFFAOYSA-J calcium sulfate hemihydrate Chemical compound O.[Ca+2].[Ca+2].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O ZOMBKNNSYQHRCA-UHFFFAOYSA-J 0.000 claims description 9
- 230000001629 suppression Effects 0.000 claims description 9
- 239000003795 chemical substances by application Substances 0.000 claims description 8
- 229920000642 polymer Polymers 0.000 claims description 8
- 239000002002 slurry Substances 0.000 claims description 8
- 150000001875 compounds Chemical class 0.000 claims description 7
- 239000007788 liquid Substances 0.000 claims description 7
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 claims description 6
- 239000004115 Sodium Silicate Substances 0.000 claims description 6
- 238000006243 chemical reaction Methods 0.000 claims description 6
- 229910052911 sodium silicate Inorganic materials 0.000 claims description 6
- 239000000126 substance Substances 0.000 claims description 6
- 239000011398 Portland cement Substances 0.000 claims description 5
- 239000011230 binding agent Substances 0.000 claims description 5
- 239000002245 particle Substances 0.000 claims description 5
- 239000002253 acid Substances 0.000 claims description 4
- 238000005260 corrosion Methods 0.000 claims description 4
- 239000003583 soil stabilizing agent Substances 0.000 claims description 4
- 238000004078 waterproofing Methods 0.000 claims description 4
- 239000001569 carbon dioxide Substances 0.000 claims description 3
- 229910002092 carbon dioxide Inorganic materials 0.000 claims description 3
- 230000007613 environmental effect Effects 0.000 claims description 3
- 230000008014 freezing Effects 0.000 claims description 3
- 238000007710 freezing Methods 0.000 claims description 3
- 230000002085 persistent effect Effects 0.000 claims description 3
- 230000008569 process Effects 0.000 claims description 3
- 230000002035 prolonged effect Effects 0.000 claims description 3
- 235000008733 Citrus aurantifolia Nutrition 0.000 claims description 2
- 235000011941 Tilia x europaea Nutrition 0.000 claims description 2
- 239000011509 cement plaster Substances 0.000 claims description 2
- 239000008187 granular material Substances 0.000 claims description 2
- 229910052602 gypsum Inorganic materials 0.000 claims description 2
- 230000035876 healing Effects 0.000 claims description 2
- 239000011508 lime plaster Substances 0.000 claims description 2
- 230000014759 maintenance of location Effects 0.000 claims description 2
- 239000010440 gypsum Substances 0.000 claims 1
- 238000012360 testing method Methods 0.000 description 27
- 238000002156 mixing Methods 0.000 description 12
- 239000004033 plastic Substances 0.000 description 10
- 229920003023 plastic Polymers 0.000 description 10
- 238000005056 compaction Methods 0.000 description 5
- 239000004567 concrete Substances 0.000 description 5
- 229910021653 sulphate ion Inorganic materials 0.000 description 5
- 239000004568 cement Substances 0.000 description 4
- 239000004615 ingredient Substances 0.000 description 4
- 230000004048 modification Effects 0.000 description 4
- 238000012986 modification Methods 0.000 description 4
- 239000004743 Polypropylene Substances 0.000 description 3
- 229920004482 WACKER® Polymers 0.000 description 3
- -1 acrylate ester Chemical class 0.000 description 3
- 230000008901 benefit Effects 0.000 description 3
- 230000008859 change Effects 0.000 description 3
- KRKNYBCHXYNGOX-UHFFFAOYSA-N citric acid Chemical compound OC(=O)CC(O)(C(O)=O)CC(O)=O KRKNYBCHXYNGOX-UHFFFAOYSA-N 0.000 description 3
- 230000006866 deterioration Effects 0.000 description 3
- 239000000839 emulsion Substances 0.000 description 3
- 238000011065 in-situ storage Methods 0.000 description 3
- 238000002360 preparation method Methods 0.000 description 3
- 150000003839 salts Chemical class 0.000 description 3
- NTHWMYGWWRZVTN-UHFFFAOYSA-N sodium silicate Chemical compound [Na+].[Na+].[O-][Si]([O-])=O NTHWMYGWWRZVTN-UHFFFAOYSA-N 0.000 description 3
- 238000011282 treatment Methods 0.000 description 3
- UWZSHGZRSZICIW-UHFFFAOYSA-N triethoxy(2,4,4-trimethylpentyl)silane Chemical compound CCO[Si](OCC)(OCC)CC(C)CC(C)(C)C UWZSHGZRSZICIW-UHFFFAOYSA-N 0.000 description 3
- UXVMQQNJUSDDNG-UHFFFAOYSA-L Calcium chloride Chemical compound [Cl-].[Cl-].[Ca+2] UXVMQQNJUSDDNG-UHFFFAOYSA-L 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 2
- 239000001110 calcium chloride Substances 0.000 description 2
- 229910001628 calcium chloride Inorganic materials 0.000 description 2
- 239000013078 crystal Substances 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- BFMKFCLXZSUVPI-UHFFFAOYSA-N ethyl but-3-enoate Chemical compound CCOC(=O)CC=C BFMKFCLXZSUVPI-UHFFFAOYSA-N 0.000 description 2
- 238000012423 maintenance Methods 0.000 description 2
- 238000011176 pooling Methods 0.000 description 2
- 238000005096 rolling process Methods 0.000 description 2
- 239000013049 sediment Substances 0.000 description 2
- 238000007711 solidification Methods 0.000 description 2
- 230000008023 solidification Effects 0.000 description 2
- 239000010959 steel Substances 0.000 description 2
- 244000007645 Citrus mitis Species 0.000 description 1
- 229920001732 Lignosulfonate Polymers 0.000 description 1
- 229910019142 PO4 Inorganic materials 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 230000004888 barrier function Effects 0.000 description 1
- 230000033228 biological regulation Effects 0.000 description 1
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 description 1
- 239000000920 calcium hydroxide Substances 0.000 description 1
- 235000011116 calcium hydroxide Nutrition 0.000 description 1
- 229910001861 calcium hydroxide Inorganic materials 0.000 description 1
- 239000000378 calcium silicate Substances 0.000 description 1
- 229910052918 calcium silicate Inorganic materials 0.000 description 1
- 239000004927 clay Substances 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 230000001186 cumulative effect Effects 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000009429 distress Effects 0.000 description 1
- 238000010410 dusting Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 230000009931 harmful effect Effects 0.000 description 1
- 230000036541 health Effects 0.000 description 1
- 150000004687 hexahydrates Chemical class 0.000 description 1
- 238000009863 impact test Methods 0.000 description 1
- 230000008676 import Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000004898 kneading Methods 0.000 description 1
- WRUGWIBCXHJTDG-UHFFFAOYSA-L magnesium sulfate heptahydrate Chemical compound O.O.O.O.O.O.O.[Mg+2].[O-]S([O-])(=O)=O WRUGWIBCXHJTDG-UHFFFAOYSA-L 0.000 description 1
- 150000004682 monohydrates Chemical class 0.000 description 1
- 150000004686 pentahydrates Chemical class 0.000 description 1
- 235000021317 phosphate Nutrition 0.000 description 1
- 150000003013 phosphoric acid derivatives Chemical class 0.000 description 1
- 229920001155 polypropylene Polymers 0.000 description 1
- 230000002250 progressing effect Effects 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- 150000004756 silanes Chemical class 0.000 description 1
- 150000004760 silicates Chemical class 0.000 description 1
- 239000010802 sludge Substances 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000003381 stabilizer Substances 0.000 description 1
- 238000007655 standard test method Methods 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 230000035882 stress Effects 0.000 description 1
- 238000004381 surface treatment Methods 0.000 description 1
- 230000008961 swelling Effects 0.000 description 1
- 150000004684 trihydrates Chemical class 0.000 description 1
- 238000005303 weighing Methods 0.000 description 1
- 239000002023 wood Substances 0.000 description 1
Landscapes
- Processing Of Solid Wastes (AREA)
Abstract
- 33 This patent relates to a stabilising composition comprising on a dry basis, at least about 10% by weight magnesium oxide, up to about 85% by weight magnesium chloride, and a further additive selected from one or more of i) about 10 to about 50% by weight magnesium sulphate, ii) about 5 to about 20% by weight calcium sulphate, iii) about 0.1 to about 5% by weight silicate or silane or mixture thereof, or iv)any combination of two or more of (i) to (iii).
Description
Regulation 3.2 AUSTRALIA PATENTS ACT, 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT ORIGINAL Name of Applicant: GRAVEL LOCK NZ LIMITED Actual Inventors: AUKETT, Lance Gordon, CLAGUE, Jeffrey John and LEWIS, Grant John Address for service AJ PARK, Level 11, 60 Marcus Clarke Street, Canberra ACT in Australia: 2601, Australia Invention Title: A Stabilising Composition The following statement is a full description of this invention, including the best method of performing it known to us. 6076665_1 -2 Field of the invention [0001] The present invention relates to a stabilising composition, and its use, comprising magnesium oxide and chloride in combination with an additive selected from one or more of magnesium sulphate, calcium sulphate, and a silicate or silane or mixture thereof. [0002] More particularly, though not solely, the composition relates to an improved composition for use as a dust controller or suppressant, in the stabilising of unsealed aggregate surfaces, as well as a stabilising improver of yet other materials or construction aggregate, including but not limited to soils, road base and wear layer materials. Background to the invention [0003] Conventional road construction is costly and typically involves replacement of unsuitable sub-soil with suitable aggregate which requires a source of asphalt or concrete. Such materials are not obtainable or affordable in many areas in developing nations and in areas served by secondary (gravel, dirt, unpaved) roads. [0004] Various methods have been attempted to stabilise unpaved roads, such as using Portland cement of hydrated lime calcium chloride and polymers. These methods are not suitable for sulphate or salt effected soils, and soils containing high levels of organics. Furthermore, if the stabilised pavements are not sealed with a bitumen or asphalt or concrete they will flush becoming brittle and then break down quickly in wet weather. [0005] Defects in road surfaces are typically classified into two categories: - surface deterioration, and - surface deformation. [0006] Surface deformations often have combined causes that include both stresses to the road surface itself and other factors such as sub-base and base capacity and stability. [0007] Surface deterioration is exemplified by "dust," the result of loss of fine binder material from road surfaces. Dust is a substantial problem for secondary roads, as the loss of these fine materials leads to other types of road distress such - 3 as loss of cohesion (leading to corrugation) and compaction of the road fill material, and reduced capacity to maintain the requisite moisture in the road fill. [0008] The problems typically associated with secondary unsealed roads are caused by - the harmful effects of water and moisture content on the road surface and base, - the lack of surface cohesion and resulting loss of road compaction caused by dust, typically caused by not enough moisture content in the ware layer, and - the heavy traffic loads exerted on roads with weak or inadequate soil, sub-base, or base. [0009] The need for treatment of unpaved roads and other outdoor surfaces to reduce maintenance and construction costs, and to control airborne dust is well recognised. In addition to reduced driver visibility and adverse health and aesthetic consequences, airborne dust indicates deterioration and actual loss of road surface. This represents a significant cost in the form of loss of aggregate and increased maintenance cycles. Much of the need for dust control is on rural, unpaved aggregate and soil roads, but dust control is as important in many other areas, such as construction sites, mines, farms, golf courses and parking lots. [0010] It is an object of the present invention to provide a stabilising composition which at least provides the public with a useful choice. [0011] Other objects of the invention may become apparent from the following description which is given by way of example only. Summary of the invention [0012] In a first aspect the invention relates to a stabilising composition comprising on a dry basis - at least about 10% by weight magnesium oxide, - up to about 85% by weight magnesium chloride, and - a further additive selected from one or more of i) about 10 to about 50% by weight magnesium sulphate, ii) about 5 to about 20% by weight calcium sulphate, iii) about 0.1 to about 5% by weight silicate or silane or mixture thereof, or -4 iv) any combination of two or more of (i) to (iii). [0013] In a further aspect the invention relates to a composition comprising on a dry basis magnesium oxide, chloride and sulphate, the composition comprising - at least about 10% by weight magnesium oxide relative to the total amount of magnesium oxide, chloride and sulphate, and - up to about 90% by weight of a blend of magnesium chloride and magnesium sulphate relative to the total amount of magnesium oxide, chloride and sulphate. [0014] In a further aspect the invention relates to a method of dust suppression and/or soil stabilisation comprising - obtaining a stabilising composition of the invention, - adding the stabilising composition to a substrate to be treated. [0015] In a further aspect the invention relates to a method of dust suppression and/or soil stabilisation comprising - adding a stabilising composition of the invention to the soil to increase the Californian Bearing ratio (CBR) of the substrate by at least about 50 to about 2000%. [0016] In a further aspect the invention relates to a method of dust suppression and/or soil stabilisation comprising - adding a stabilising composition of the invention to the soil to reduce the Plasticity Index of the soil being stabilised by at least 40%. [0017] The following embodiments may relate to any of the above aspects. [0018] In some embodiments the composition comprises at least about 10% by weight magnesium oxide, and up to about 9 0% by weight of a blend of magnesium chloride and magnesium sulphate [0019] In some embodiments the mixture comprises - at least about 10% by weight magnesium oxide, - up to about 9 0% by weight of a blend of magnesium chloride and magnesium sulphate. [0020] In some embodiments the mixture comprises - from about 10 to about 50% by weight magnesium oxide, - 5 from about 50 to about 90% by weight of a blend of magnesium chloride and magnesium sulphate. [0021] In some embodiments the mixture comprises about 20 to about 50% by weight magnesium oxide. [0022] In some embodiments the mixture comprises about 30 to about 50% by weight magnesium oxide. [0023] In some embodiments the purity of the magnesium oxide is at least about 50%. [0024] In some embodiments the purity of the magnesium oxide is at least about 50% to about 80%. [0025] In some embodiments the particle size of the magnesium oxide is about 100 to about 400 mesh. [0026] In some embodiments the magnesium chloride has a purity of at least about 40%. [0027] In some embodiments the magnesium sulphate has a purity of at least about 60%. [0028] In some embodiments the composition comprises from about 65 to about 9 5% magnesium chloride by weight relative to the blend of magnesium chloride and magnesium sulphate. [0029] In some embodiments the composition comprises from about 5 to about 35% magnesium sulphate by weight relative to the blend of magnesium chloride and magnesium sulphate. [0030] In some embodiments the composition comprises from about 8 to about 20% magnesium sulphate by weight relative to the blend of magnesium chloride and magnesium sulphate. [0031] In some embodiments the composition comprises from about 10 to about 15% magnesium sulphate by weight relative to the blend of magnesium chloride and magnesium sulphate.
-6 [0032] In some embodiments the composition comprises about 75 to about 95% by weight of magnesium chloride relative to the total amount of magnesium chloride and magnesium sulphate. [0033] In some embodiments the composition comprises about 5 to about 25% by weight of magnesium sulphate relative to the total amount of magnesium chloride and magnesium sulphate. [0034] In some embodiments the mixture comprises from about 32 to about 85% by weight magnesium chloride. [0035] In some embodiments the mixture comprises from about 5 to about 35% by weight magnesium sulphate. [0036] In some embodiments the mixture comprises from about 4 to about 18% by weight magnesium sulphate. [0037] In some embodiments the mixture comprises from about 5 to about 13% by weight magnesium sulphate. [0038] In some embodiments the composition comprises from about 5 to about 2 5% by weight calcium sulphate. [0039] In some embodiments the composition comprises from about 5 to about 2 0% by weight calcium sulphate. [0040] In some embodiments the composition comprises from about 10 to about 15% by weight calcium sulphate [0041] In some embodiments the calcium sulphate is selected from one or more of gypsum, lime or cement plaster. [0042] In some embodiments the calcium sulphate is plaster of paris. [0043] In some embodiments the composition comprises any one or more of - a water resistant compound, - an anti-corrosion agent, - an acid, or - any combination of any two or more thereof. [0044] In some embodiments the composition comprises any one or more of -7 - calcium sulphate, - portland cement, - sodium silicate, - lignosulphate, - an organosilicon waterproofing agent, - a polymer compound,
-
silane, - a silicate, - bitumen, or - any combination of any two or more thereof. [0045] In some embodiments the composition comprises about 0.01 to about 2.1% by weight silane and/or silicate. [0046] In some embodiments the composition comprises about 0.5 to about 1.1% by weight silane and/or silicate. [0047] In some embodiments the composition comprises about 0.5 to about 10% by weight lignosulphate. [0048] In some embodiments the composition comprises about 0.5 to about 1.0% by weight lignosulphate. [0049] In some embodiments the composition comprises a soil stabiliser binder. [0050] In some embodiments the composition comprises water. [0051] In some embodiments the composition is in the form of a powder, particle, prill or granule. [0052] In some embodiments the composition is in the form of a wetted mixture, liquid or slurry. [0053] In some embodiments the magnesium chloride and additive are blended prior to combination with magnesium oxide. [0054] In some embodiments the magnesium chloride and magnesium sulphate are blended prior to combination with magnesium oxide.
-8 [0055] In some embodiments the blend is wetted prior to combining with the magnesium oxide. [0056] In some embodiments water is added to the composition mix. [0057] In some embodiments the composition is added to the soil to be treated for a purpose selected from one or more of - increasing the chemical stability of a soil, road base, subgrade, sub base or wear course, - increasing the strength of the road surface, - increasing the hygroscopic road surface, - increasing the useful life of a road bed, - increasing the strength of the road surface for re-grading and re healing, - providing a carbon dioxide sequestering system, - increasing the strength of a road surface that maintains its strength after prolonged exposure to environmental impact such as dry periods and persistent rains, - increasing the strength of a road surface or road base that maintains its superior strength and has the ability to hydrate and dry out soils with an exothermic reaction, - lowering the freezing point of the materials treated, and - increasing the build or construction process. [0058] In some embodiments the addition of the stabilising composition to the treated substrate reduces the Plasticity Index of the treated substrate by at least 40, 45, 50, 55, 60, 65, 70, 75, 80, 85 or 90%. [0059] Preferably the substrate is soil, road base, subgrade, sub-base or wear course. [0060] In some embodiments use of the composition of the invention increases the Californian Bearing ratio (CBR) of the substrate. [0061] In some embodiments use of the composition of the invention increases the Californian Bearing ratio (CBR) of the substrate by at least 50, 100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700, 1800, 1900 or 2000%.
-9 [0062] In some embodiments use of the composition of the invention increases the Californian Bearing ratio (CBR) of the substrate from about 0.5 to about 2 to at least 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 or 16. [0063] In some embodiments the components of the composition are combined together with subsequent water addition to form a slurry. [0064] In some embodiments the soluble components of the composition are first hydrated, and then the insoluble components are added to the hydrated soluble components. [0065] This invention may also be said broadly to consist in the parts, elements and features referred to or indicated in the specification of the application, individually or collectively, and any or all combinations of any two or more said parts, elements or features, and where specific integers are mentioned herein which have known equivalents in the art to which this invention relates, such known equivalents are deemed to be incorporated herein as if individually set forth. [0066] It is intended that reference to a range of numbers disclosed herein (for example, 1 to 10) also incorporates reference to all rational numbers within that range (for example, 1, 1.1, 2, 3, 3.9, 4, 5, 6, 6.5, 7, 8, 9 and 10) and also any range of rational numbers within that range (for example, 2 to 8, 1.5 to 5.5 and 3.1 to 4.7) and, therefore, all sub-ranges of all ranges expressly disclosed herein are hereby expressly disclosed. These are only examples of what is specifically intended and all possible combinations of numerical values between the lowest value and the highest value enumerated are to be considered to be expressly stated in this application in a similar manner. [0067] The invention consists in the foregoing and also envisages constructions of which the following gives examples only. Detailed description of the invention Definitions [0068] As used herein the term "and/or" means "and" or "or", or both. [0069] The term "comprising" as used in this specification means "consisting at least in part of". When interpreting each statement in this specification that includes the term "comprising", features other than that or those prefaced by the - 10 term may also be present. Related terms such as "comprise" and "comprises" are to be interpreted in the same manner. Composition [0070] In one embodiment the present invention relates to a composition comprising by dry weight - at least about 10% by weight magnesium oxide, - up to about 85% by weight magnesium chloride, and - a further additive selected from one or more of i) about 10 to about 50% by weight magnesium sulphate, ii) about 5 to about 20% by weight calcium sulphate, iii) about 0.1 to about 5% by weight silicate or silane or mixture thereof, or iv) any combination of two or more of (i) to (iii). [0071] In one embodiment the present invention relates to a composition comprising magnesium oxide, chloride and sulphate, the composition comprising by dry weight - at least about 10% by weight magnesium oxide relative to the total amount of magnesium oxide, chloride and sulphate, and - up to about 90% by weight of a blend of magnesium chloride and magnesium sulphate relative to the total amount of magnesium oxide, chloride and sulphate. [0072] In one embodiment the present invention relates to a composition comprising by dry weight - from about 10 to about 50% by weight magnesium oxide, - from about 50 to about 90% by weight of a blend of magnesium chloride and magnesium sulphate. [0073] In a further aspect the invention relates to a method of dust suppression and/or soil stabilisation comprising - adding a stabilising composition of the invention to the soil to reduce the Plasticity Index of the soil being stabilised by at least 40%. [0074] In a further aspect the invention relates to a method of dust suppression and/or soil stabilisation comprising - 11 adding a stabilising composition of the invention to the soil to increase the Californian Bearing ratio (CBR) of the substrate by a least about 50 to about 2000%. [0075] The Californian Bearing ratio is an impact test that is covered by New Zealand standard NZS 4402:1986:6.1.1. [0076] Other relevant standards include NZS 4402:1986:2.1 for water content and NZS 4402:1986:4.1.1 for soil compaction tests (determination of the dry density/water content relationship). [0077] In some embodiments the composition comprises about 50, 55, 60, 65, 70, 75, 80, 85 or 90% of the blend of magnesium chloride and magnesium sulphate relative to the total amount of magnesium oxide, from about chloride and sulphate, from about and useful ranges may be selected between any of these values (for example, about 50 to about 90, about 50 to about 80, about 50 to about 70, about 50 to about 60, about 55 to about 90, about 55 to about 75, about 55 to about 70, about 65 to about 90, about 65 to about 85, about 65 to about 80, about 65 to about 70, about 70 to about 90, about 70 to about 85, about 70 to about 80, about 80 to about 90 or about 85 to about 9 0% of the blend of magnesium chloride and magnesium sulphate relative to the total amount of magnesium oxide, about chloride and sulphate). [0078] In some embodiments the composition includes one or more additives selected from - water resistant compound, - anti-corrosion agent, - compound that increases water resistance, and - an acid. [0079] A water resistant compound can be sodium silicate, ethyl vinyl acetate (EVA), bitumen emulsion or one of the SILRES@ WACKER range. [0080] An anti- corrosion agent can be sodium silicate. [0081] A suitable acid can be HCI or citric acid. [0082] In some embodiments the composition includes one or more additives selected from - 12 - portland cement, - sodium silicate, - lignosulphate, - a polymer compound, - organosilicon waterproofing agent,
-
silane, - a silicate, - bitumen, or - any combination of two or more thereof. [0083] In some embodiments the composition comprises a soil stabiliser binder. For example, the soil stabiliser binder may be an acrylate ester polymer. In some embodiments the acrylate ester polymer is in the form of an emulsion. [0084] In some embodiments the silicate or silane or mixture thereof comprises a triethoxy (2,4,4-trimethylpentyl) silane. Magnesium oxide [0085] Magnesium oxide is also known as magnesia and has the chemical formula MgO. [0086] In some embodiments the composition of the invention contains about 20, 25, 30, 35, 40, 45, or 50% by weight magnesium oxide, and useful ranges may be selected between any of these values (for example, about 20 to about 50, about 20 to about 40, about 20 to about 30, about 25 to about 50, about 25 to about 45, about 25 to about 35, about 25 to about 30, about 30 to about 50, about 30 to about 40, about 35 to about 50, about 35 to about 45, about 40 to about 50 or 45 to about 50% by weight magnesium oxide). [0087] In some embodiments the purity of the magnesium oxide is at least about 50, 55, 60, 65, 70, 75, 80, 85 or 90%, and useful ranges may be selected between any of these values (for example, about 50 to about 90, about 50 to about 80, about 50 to about 70, about 50 to about 60, about 55 to about 90, about 55 to about 85, about 55 to about 75, about 55 to about 65, about 60 to about 90, about 60 to about 85, about 60 to about 75, about 60 to about 70, about 70 to about 90, about 70 to about 80, about 75 to about 90, about 75 to about 85 or about 80 to about 90% purity).
- 13 [0088] A composition of any one of claims 1 to 8 wherein the particle size of the magnesium oxide is about 100, 150, 200, 250, 300, 350 or 400 mesh. [0089] The mesh number is the number of openings across one linear inch of screen. For example, a 100 mesh screen has 100 openings. A 100 mesh has an approximately 150 micron space between wires, and a 400 mesh has an approximately 37 micron space between wires. Magnesium chloride [0090] The magnesium chloride may be in various forms, including anhydrous and hydrated forms (e.g. anhydrous to hexahydrate). [0091] In some embodiments the purity of the magnesium oxide is at least about 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95 or 99%, and useful ranges may be selected between any of these values (for example, about 40 to about 99, about 40 to about 95, about 40 to about 80, about 40 to about 75, about 40 to about 65, about 40 to about 50, about 45 to about 99, about 45 to about 75, about 45 to about 65, about 50 to about 99, about 50 to about 80, about 50 to about 70, about 55 to about 99, about 55 to about 96, about 55 to about 90, about 50 to about 80, about 50 to about 70, about 50 to about 60, about 60 to about 99, about 69 to about 90, about 60 to about 80, about 75 to about 99, about 75 to about 90, about 75 to about 85, about 75 to about 80, about 80 to about 99, about 80 to about 90, or about 90 to about 99% purity). [0092] In some embodiments the magnesium chloride is in the form of a flake, prill, powder or aqueous form. Magnesium sulphate [0093] In some embodiments the magnesium sulphate is in a hydrated form. For example, the magnesium sulphate may be selected from magnesium sulphate heptahydrate, anhydrate, monohydrate, trihydrate, dehydrate or pentahydrate. [0094] In some embodiments the purity of the magnesium oxide is at least about 60, 65, 70, 75, 80, 85, 90, 95 or 99%, and useful ranges may be selected between any of these values (for example, about 60 to about 99, about 60 to about 95, about 60 to about 90, about 60 to about 80, about 60 to about 70, about 65 to about 99, about 65 to about 95, about 65 to about 85, about 65 to about 75, about 70 to about 99, about 70 to about 90, about 70 to about 80, about 75 to about 99, - 14 about 75 to about 95, about 75 to about 90, about 75 to about 80, about 80 to about 99, about 80 to about 90, about 85 to about 99, about 85 to about 95, about 85 to about 90, about 90 to about 99 or about 90 to about 95% purity). [0095] In some embodiments the magnesium sulphate is in a flake, prill, powder or aqueous form. [0096] In some embodiments the magnesium sulphate is pre-mixed. [0097] In some embodiments the magnesium sulphate is in crystal or solid form. Blend of Magnesium chloride and sulphate [0098] In some embodiments the composition contains a blend of magnesium chloride and magnesium sulphate. [0099] In some embodiments the composition comprises about 50, 55, 60, 65, 70, 75, 80, 85, or 90% of a blend of magnesium chloride and magnesium sulphate by weight of the composition, and useful ranges may be selected between any of these values (for example, about 50 to about 90, about 50 to about 85, about 50 to about 80, about 50 to about 70, about 50 to about 60, about 55 to about 90, about 55 to about 85, about 55 to about 80, about 55 to about 70, about 55 to about 60, about 60 to about 90, about 60 to about 80, about 60 to about 75, about 60 to about 70, about 70 to about 90, about 70 to about 80, about 75 to about 90, about 75 to about 85, about 75 to about 80 or about 80 to about 90% of a blend of magnesium chloride and magnesium sulphate by weight of the composition). [0100] In some embodiments the composition comprises 65, 70, 75, 80, 85, 90 or 95% magnesium chloride by weight relative to the blend of magnesium chloride and magnesium sulphate, and useful ranges may be selected between any of these values (for example, about 65 to about 95, about 65 to about 90, about 65 to about 85, about 65 to about 80, about 65 to about 70, about 70 to about 95, about 70 to about 90, about 70 to about 80, about 70 to about 75, about 75 to about 96, about 75 to about 85, about 75 to about 80, about 80 to about 95, about 80 to about 90, about 85 to about 95, about or about 90 to about 95% magnesium chloride by weight relative to the blend of magnesium chloride and magnesium sulphate).
- 15 [0101] In some embodiments the composition comprises 5, 10, 15, 20, 25, 30 or 35% magnesium sulphate by weight relative to the blend of magnesium chloride and magnesium sulphate, and useful ranges may be selected between any of these values (for example, about 5 to about 35, about 5 to about 30, about 5 to about 20, about 5 to about 15, about 10 to about 35, about 10 to about 30, about 10 to about 20, about 10 to about 15, about 15 to about 35, about 15 to about 30, about 15 to about 25, about 15 to about 20, about 20 to about 35, about 20 to about 30, about 25 to about 35 or about 30 to about 35% magnesium sulphate by weight relative to the blend of magnesium chloride and magnesium sulphate). [0102] In some embodiments the magnesium chloride and magnesium sulphate are blended prior to mixing with the other components of the invention. [0103] In alternate embodiments the magnesium chloride and magnesium sulphate are blended with or after addition of a component to one or other of the magnesium chloride or magnesium sulphate. Preparation of the composition of the invention [0104] Any blending method known in the art can be used to mix the ingredients of the present invention. [0105] There are two different types of mixing. The first is convective mixing material in which the mixer is transported from one location to another. This type of mixing process leads to a less ordered state inside the mixer. The components to be mixed become distributed over the other components. With progressing time the mixture will become more and more randomly ordered. After certain mixing time the ultimate random state is reached. This type of mixing is suitable for application to free-flowing and coarse materials. [0106] Convective mixers suitable for use in the invention include silo mixers, horizontal mixers, ribbon mixers and conical mixers. [0107] In some embodiments the blending time for the components is about 1 to about 120 minutes. [0108] In some embodiments the mesh size of the powder is below 200 mesh. However, it should be appreciated that mesh sizes greater than 200 mesh can be used.
- 16 [0109] Typically the magnesium oxide is stored, for example in closed silos, prior to use. In some embodiments the magnesium oxide is wrapped in plastic sacks or bags. Once selected for use the dry magnesium oxide and one or more of the components of the invention are mixed with a volume of water to create a slurry, or the water can be add on-site. [0110] In some embodiments the amount of water added is from about 15 to about 40% by weight. [0111] It should be appreciated that the mixing period of the composition with water until solidification can vary. For example, as the amount of magnesium oxide decreases the period between the mixing of the dry product with water and the start of solidification is extended, specifically from about 5 minutes to as much as 30 hours. [0112] In some embodiments each of the components of the composition of the invention are mixed. For example, magnesium oxide is mixed with magnesium chloride and one or more of the additives (e.g. magnesium sulphate, calcium sulphate, silicate or silicane or mixture thereof). Preferably the components are mixed with a constant percentage of water. i.e. the powder is added to the surface at the same time as the composition of the invention is added. [0113] In some embodiments the magnesium oxide dry product is blended with water into a viscous mixture. In some embodiments the amount of water added is about 15 to about 30% by weight relative to the amount of magnesium oxide. [0114] The composition of the invention can be stored. In some embodiments the composition of the invention is stored to maintain the composition air tight. In some embodiments the composition of the invention is stored in a silo, such as a tower silo, bunker silo, or bag silo, or a bag. A tower silo can be formed from wood staves, concrete staves, cast concrete, and steel panels. Bunker silos are trenches, usually with concrete walls, that are filled and packed with tractors and loaders. The filled trench is covered with a plastic tarp to make it airtight. These silos are usually unloaded with a tractor and loader. Bag silos are heavyweight plastic tubes, typically around 2 to about 4 meters in diameter, and of variable length as required for the amount of material to be stored. They are packed using a machine made for the purpose, and sealed on both ends. Bag silos may be unloaded using a tractor - 17 and loader or skid-steer loader. When in use the bag is discarded in sections as it is torn off. In some embodiments where the bag is used for storage the bag is a 10 to about 50 kg bag such as a plastic bag, woven cement bag, polypropylene cement bags. It should be appreciated that one requirement of the bag is that the bag substantially prevents atmospheric humidity water ingress or exposure to the air to substantially change the chemical makeup of the composition of the invention. [0115] In some embodiments a bulk bag is used to store the composition of the invention. It should be appreciated that one requirement of the bulk bag is that the bag substantially prevents ingress of atmospheric humidity, water or air in a form to substantially change the chemical makeup of the composition of the invention. Examples of bulk bags include jumbo bags (bulk bag or FIBC), round or square type, have carrying capacity range from 0.5T to 3Ts, volume from 500 L to 2300 L. Typically such bulk bags have a bottom shoot for unloading. Such bags may come in various shapes such as round or square. The bags may be lined with plastic infill bags or water resistant barriers for transporting through humid conditions. In some embodiments the blended and bagged composition of the invention is stored on pallets or similar to keep stored bags off the ground and in a dry place. Use of the composition [0116] The composition of the present invention can be used in both roading and non-roading applications. [0117] For example, in some embodiments non-structural applications (modification) are designed to dry up mud soils, organic sludge aggregate or clays and create working platforms in a variety of construction settings. [0118] In other embodiments, structural applications (stabilisation) include non-roading pavements, such as airports, parking lots, and racetracks; and other applications such as building foundations and embankment stabilisation and road shoulder stabilisation. [0119] It should be appreciated that the construction techniques used for roading and non-roading application of the composition of the invention are essentially the same.
- 18 [0120] In some embodiments, when used on site the composition of the invention is in a dry powder form that is homogenously mixed into the materials to be treated. It will be appreciated that the method can be performed either off-site and the treated material transported to the site of use, or carried out in situ. [0121] If carrying out the in situ method, typically the material to be treated, for example soil, is first loosened prior to addition of the composition of the invention, which may be applied in dry, liquid or slurried form. Typically the equipment used includes a power rake, grader or full-depth reclamation equipment, or the equivalent to mechanically loosen the soil. [0122] In some embodiments the mixture of the composition of the invention and the materials to be treated are wetted, preferably with water, to create a chemical reaction to treat the materials that the composition of the invention is mixed into. [0123] In some embodiments the composition of the invention is applied to soils, road bases, sub-grades, sub-bases and wear courses as a pre-mixed mixture. [0124] In other embodiments the mixture of the composition of the invention is mixed with material to be treated, that are soluble (magnesium chloride, magnesium sulphate in prilled form, polymer, bitumen emulsion, silane and lingnosulphate and sodium silicate), by mixing with water. The mixture can then be applied to components that are not soluble (e.g. magnesium oxide, plaster of paris, cement and magnesium sulphate in powder form) and then can be homogenously mixed into the material to be treated. [0125] In some embodiments the composition of the invention is applied dry to the material to be treated, and subsequently water (about 15 to about 60% by weight) and/or additives are then applied to the material to be treated. In some embodiments the additives are selected from Plaster of paris, Portland cements, lignosulfonates, silicate compounds or soluble phosphates, bitumen, polymers, water proofing agents such as silanes. In some embodiments the use of the additives may improve any one or more characteristics selected from improved economics, strength, compressibility, hydraulic conductivity, hygroscopic potential, hydroscopic properties, workability, swelling potential, sulphate attack and volume change tendencies.
- 19 [0126] In some embodiments the amount of water added is sufficient to hydrate the dry powder to enable the composition of the invention and the material to be treated to dissolve and mix together. [0127] In other embodiments the water used to hydrate the dry powder may also contain the soluble components of the material to be treated. In some embodiments the water has a specific gravity about 1.1 to about 1.5. [0128] In some embodiments water is added to the composition of the invention to form a slurry. In such embodiments the slurry may then be added or blended to the material to be treated. [0129] In some embodiments of the composition of the invention is homogenously mixed with the material to be treated off-site, with subsequent water addition at the site of application. [0130] The water typically is sourced from a water tank truck or large hydroseed equipment, or the equivalent. The water is used to create a chemical reaction. A power rake, full-depth reclamation equipment or equivalent may be used again to mechanically mix the improved composition into the soil. In some embodiments the water may be injected at the time of the mechanical mixing into the drum of a mechanical mixer and then a motor grader can be used to contour the surface as desired. [0131] A vibratory roller, vibratory plate, steel drum roller or rubber wheeled rollers, or other equipment appropriate for compacting may be used for complete compaction of the material that has been treated with the improved composition. [0132] In some embodiments the addition of the stabilising composition to the soil, road base, subgrade, sub-base or wear course to be treated reduces the Plasticity Index by at least 40, 45, 50, 55, 60, 65, 70, 75, 80, 85 or 90%, and useful ranges may be selected between any of these values (for example, about 40 to about 90, about 40 to about 80, about 40 to about 70, about 40 to about 60, about 40 to about 50, about 45 to about 90, about 45 to about 90, about 45 to about 75, about 45 to about 65, about 45 to about 60, about 55 to about 90, about 55 to about 80, about 55 to about 70, about 65 to about 90, about 65 to about 80, about 65 to about 70, about 70 to about 90, about 70 to about 80, about 75 to about 90, about 75 to about 85, about 80 to about 90%).
- 20 Roading application [0133] In some embodiments of the present invention, the composition of the present invention can be used both on unpaved roads that will remain un-surfaced to roads that will receive running surface treatments. [0134] In some embodiments the composition of the present invention is mixed into new construction or native roadbed soils, old gravelled roads, or recycled roadway surface materials. Used in this manner the use of the composition of the present invention can - provide an improved composition for chemical improvement to the soils, road bases, subgrades, sub-bases and wear courses, - increase the strength of the road surface by, for example, o absorbing carbon dioxide from the atmosphere, o creating a hygroscopic surface that is less likely to break down and produce dust and has less sediment run off, - create a road surface that remains hygroscopic keeping a higher moisture content in the pavement when compared to untreated roads, - increase the useful life of the road bed and to the surface ware layers, - provide a stronger road surface that can be re-graded and can be re healed, - create a stronger road surface that maintains its strength after prolonged exposure to environmental impact such as dry periods and persistent rains, - creates a stronger road surface that maintains its strength by remaining hygroscopic and keeping higher moisture content for longer periods in the pavement than roads treated with solutions of magnesium chloride and calcium chloride brines alone, - create a stronger road surface or road base that maintains its superior strength and has the ability to hydrate and dry out soils with an exothermic reaction, - lower the freezing point of the materials treated, and/or - create a faster building method.
- 21 [0135] In some embodiments the composition is blended, in differing percentages, with in-place soils to engineer improved roadways by stabilising the sub-base subgrade and ware layers of the roads treated pavements. [0136] In some embodiments, the use of the composition in this manner minimises dust and gravel loss creating less sediment. Non-roading applications Airports [0137] In some embodiments the composition can be used in soil treatment options for airport construction. [0138] For example, many airports are built on already existing properties therefore having little control over terrain and soil conditions, or are built on reclaimed land that will likely include salt affected soils. In most cases if marginal or poor soil conditions are encountered, the owner will choose to remove and replace the existing soils. [0139] As an alternative, use of the composition of the invention can allow the use of existing in situ soils. [0140] In some embodiments the use of the present invention in a slurry form will assist in minimising dusting of airplanes and mechanical equipment. [0141] The use of the composition of the invention to dry and modify marginal and poor soils may also assist in keeping projects on schedule during wet weather by providing a working table that sheds water and allows return to work more quickly after rain events. Commercial [0142] In some embodiments the composition of the invention can be used in the construction of large buildings and the accompanying parking areas for stabilisation or modification. [0143] Stabilisation/modification techniques are generally the same as those described for subgrade, subbase and base course construction. [0144] In some embodiments the material excavated for building pads can be stabilised in lifts as it is removed and stored in a stockpile. The treated material can then be compacted in lifts without delay as it is returned to the building pad.
- 22 [0145] In some embodiments, the use of the composition of the invention provides sound pavement foundations and reduces the thickness of the overlying layers. [0146] As described above, in some embodiments the use of the composition of the invention for pavement layers can be used to dry overly wet soil prior to compaction. For example, in some embodiments the use of the composition of the invention maintains a firm working table that sheds moisture. Housing [0147] The development of subdivisions begins with the establishment of access roads and related utilities, followed by the construction of sidewalks, driveways, and homes. [0148] In some embodiments the use of the composition of the invention, when used for pavement layers, can be used to create structural foundations for building pads, sidewalks, and streets, and can be used to minimise the effects of weather and marginal soils. [0149] One advantage of the present invention is use of the composition of the invention in the beginning phase of construction to modify the soil and then to use additional treatments for drying trench fills. In some embodiments stabilised soils can also be used as a foundation for the final pavement. [0150] In some embodiments the composition of the invention can be used to stabilise the soil to minimize sinking and buckling. [0151] In some embodiments the composition of the invention can be used to modify and stabilise the driveway area and building pad. Embankment Stabilisation [0152] Often, inferior or overly wet borrow materials are used to construct embankments. [0153] In some embodiments the use of the composition of the invention can be used to stabilise these soils either when they are first constructed, or as part of repairing failed embankments. [0154] In some embodiments the use of the composition of the invention reduces the Plasticity Index of soil to be stabilised. The Plasticity Index (PI) is a - 23 measure of how much water a soil can absorb before dissolving into a solution. The higher the number, the more plastic and weaker the material. For example, plastic soils containing clay have PIs of 10 to 50 or more. Soils with PIs less than 10 generally do not react as readily with other stabilisers (e.g. lime and cement), especially where the soils have high organics or the soils have high sulphate or salt levels. However, in some embodiments of the invention the composition of the invention has the ability to stabilise PIs less than 10. [0155] The PI is the difference between the liquid limit and the plastic limit (see ASTM D4318-00 "Standard Test Methods for Liquid Limit, Plastic Limit, and Plasticity Index of Soils.") The tests are performed on material passing a 425 mm (No. 40) sieve. Each test measures the moisture content of the soil under certain conditions. Laboratory equipment such as a drying oven and weighing scales are required for both tests. The liquid limit test uses a simple apparatus. The plastic limit test requires hand rolling a thread of soil, kneading it, rolling it again, and repeating the procedure until the soil thread crumbles. Advantages [0156] The use of the composition of the present invention provides a number of advantages that include any one or more of the following aspects. - Eliminates the need to import costly base or aggregate materials to build a sub-base or ware course replacing subsequent paving or chip sealing requirements and binding the road surface to a strength that can be re-worked if necessary. - Produces lighter surfaces that do not absorb as much heat as traditional methods. - Create an exothermal reaction to dry out water logged soils. Example [0157] A study was carried out to determine the suitability of various compositions as dust suppression and stabilisation compositions based on their strength and moisture characteristics. Experimental setup [0158] The following combination of ingredients were tested. 1) Magnesium oxide and magnesium chloride.
- 24 2) Magnesium oxide and magnesium sulphate. 3) Magnesium oxide, magnesium chloride, and magnesium sulphate. 4) Magnesium oxide, magnesium chloride, and plaster of paris (gypsum plaster). 5) Magnesium oxide, magnesium chloride, and SILRES@ BS Powder (Wacker), a triethoxy (2,4,4-trimethylpentyl) silane. 6) Magnesium oxide, magnesium chloride, magnesium sulphate and plaster of paris. 7) Magnesium oxide, magnesium chloride, magnesium sulphate, plaster of paris and lignosulphate compund. 8) Magnesium oxide, magnesium chloride, magnesium sulphate, plaster of paris and SILRES@ BS Powder. [0159] The relevant ingredients were weighed out and combined into a mould where they were mixed by hand stirring. [0160] Thirty or sixty grams of water was then added and the mixture was stirred vigorously for 60 seconds. Following a waiting period of 5 mins the composition was then stirred vigorously again for 60 seconds and left to set. Once set the composition was removed from the mould. [0161] The moisture of the test compositions was accessed visually by inspecting the plugs outside the moulds for droplets of water or saturation. The moisture rating system is shown in Table 1. [0162] The strength of the test compositions was determined by accessing the drill depth of a dremal drill allowed to drill into the surface of the test composition under its own weight. The strength rating system is shown in Table 1. Table 1. Rating system used to rate the effectiveness of the test compositions. Strength Rating Moisture Rating Cracked -1 Failed sample -1 remained liquid state 0 Growing crystals 0 Very soft 1 Not Drawing Moisture 1 Soft 2 Slightly Draws Moisture 2 Hard but can dent 3 Limited moisture draw 3 Hard 4 Draws moisture 4 Very Hard 5 Sample covered in moisture 5 Extremely Hard 6 Moisture pooling around 6 sample - 25 [0163] An assessment of the strength scores for each test composition was carried out at 12 hours, 24 hours, 7 days and 28 days after preparation of the test compositions. [0164] An assessment of the moisture scores for each test composition was carried out at 1, 7 and 28 days after preparation of the test compositions. In relation to moisture assessment, the best samples showed pooling of water around the samples. [0165] The results for each test composition were then averaged to give a final strength and moisture score. The two scores were then added together to give a "dust rating" score. [0166] A higher score reflects a test composition hat performed better, and a lower score reflects a test composition that performs worse. Results [0167] The results are shown in Table 2. [0168] A description of each column of Table 2 is given below. - Cost shows the relative cost of each test composition taking into account the market cost of the ingredient and the amount used. - Dust rating is the cumulative score from the Strength and Moisture columns. - Strength gives the average score from each of the four strength assessment timepoints using the ranking system of Table 1. - Moisture gives the average score from each of the three moisture assessment timepoints using the ranking system of Table 1. - Oxide % gives the purity of the magnesium oxide used in the test composition. - MgO is the amount of magnesium oxide in the test composition. - MgCl 2 is the amount of magnesium chloride in the test composition. - MgSO 4 is the amount of magnesium sulphate in the test composition. - PP is the amount of plaster of paris in the test composition. - Silicate is the amount of SILRES@ BS POWDER Wacker Triethoxy(2,4,4-trimethylpentyl) silane in the test composition. [0169] Water is the amount of water in the test composition.
- 26 Table 2. Results of the study investigating the effectiveness of the test compositions # Cost Dust Strength Moisture Oxide MgO MgCl 2 MgSO 4 PP Ligno Silicate Water rating % (g) (g) (g) (g) (g) (g) (g) 1 0.42 6.67 5.00 1.67 89 60 40 30 2 0.40 5.25 4.25 1.00 95 50 50 30 3 0.40 5.50 4.50 1.00 89 50 50 30 4 0.40 5.00 4.00 1.00 69 50 50 30 5 0.35 6.25 5.25 1.00 89 40 50 30 6 0.30 4.00 3.00 1.00 90 10 90 60 7 0.32 4.25 3.25 1.00 90 20 80 60 8 0.34 5.00 4.00 1.00 90 30 70 60 9 0.36 5.50 4.50 1.00 90 40 60 60 10 0.38 5.75 4.75 1.00 90 50 50 60 11 0.35 9.42 4.75 4.67 89 20 75 5 30 12 0.35 9.17 4.50 4.67 89 20 70 10 30 13 0.35 8.92 4.25 4.67 89 20 65 15 30 14 0.34 8.92 4.25 4.67 89 20 60 20 30 15 0.35 10.25 4.25 6.00 89 20 75 5 30 16 0.35 9.42 3.75 5.67 89 20 70 10 30 17 0.35 8.75 3.75 5.00 89 20 65 15 30 18 0.34 8.00 4.00 4.00 89 20 60 20 30 19 0.40 8.75 2.75 6.00 89 10 89 1 30 20 0.42 9.75 4.75 5.00 89 20 79 1 30 21 0.43 8.33 5.00 3.33 89 30 69 1 30 22 0.39 7.83 4.50 3.33 89 45 45 5 5 30 23 0.36 9.00 3.00 6.00 89 37.5 37.5 10 10 30 24 0.35 8.58 4.25 4.33 89 20 75 2.5 2.5 30 25 0.35 7.75 3.75 4.00 89 20 65 7.5 7.5 30 26 0.34 7.75 3.75 4.00 89 20 59 10 10 30 27 0.36 7.58 4.25 3.33 89 25 69 2.5 2.5 1 30 28 0.36 7.83 4.50 3.33 89 25 64 5 5 1 30 29 0.42 7.83 4.50 3.33 89 47.5 47.5 2.5 0.25 5 30 30 0.42 7.00 5.00 2.00 89 25 69 2.5 2.5 1 30 31 0.42 7.67 5.00 2.67 89 25 64 5 5 1 30 [0170] Compositions (3) to (8) of paragraph [0158] had a higher Dust rating than compositions (1) and (2). [0171] Also demonstrated is that a lower purity of magnesium oxide did not affect the performance of the test materials.
- 27 [0172] The foregoing description of the invention includes preferred forms thereof. Modifications may be made thereto without departing from the scope of the invention.
Claims (37)
1. A stabilising composition comprising on a dry basis - at least about 10% by weight magnesium oxide, - up to about 85% by weight magnesium chloride, and - a further additive selected from one or more of i) about 10 to about 50% by weight magnesium sulphate, ii) about 5 to about 20% by weight calcium sulphate, iii) about 0.1 to about 5% by weight silicate or silane or mixture thereof, or iv) any combination of two or more of (i) to (iii).
2. A stabilising composition of claim 1 comprising magnesium oxide, chloride and sulphate, the composition comprising - at least about 10% by weight magnesium oxide relative to the total amount of magnesium oxide, chloride and sulphate, and - up to about 90% by weight of a blend of magnesium chloride and magnesium sulphate relative to the total amount of magnesium oxide, chloride and sulphate.
3. A stabilising composition of claim 1 or 2 wherein the mixture comprises - from about 10 to about 50% by weight magnesium oxide, - from about 50 to about 90% by weight of a blend of magnesium chloride and magnesium sulphate.
4. A stabilising composition of any one of claims 1 to 3 wherein the mixture comprises about 20 to about 50% by weight magnesium oxide.
5. A stabilising composition of any one of claims 1 to 4 wherein the purity of the magnesium oxide is at least about 50%.
6. A stabilising composition of any one of claims 1 to 5 wherein the particle size of the magnesium oxide is about 100 to about 400 mesh.
7. A stabilising composition of any one of claims 1 to 6 wherein the magnesium chloride has a purity of at least about 40%. - 29
8. A stabilising composition of any one of claims 1 to 7 wherein the composition comprises from about 65 to about 95% magnesium chloride by weight relative to the blend of magnesium chloride and magnesium sulphate.
9. A stabilising composition of any one of claims 1 to 8 wherein the composition comprises from about 5 to about 35% magnesium sulphate by weight relative to the blend of magnesium chloride and magnesium sulphate.
10. A stabilising composition of any one of claims 2 to 9 wherein the composition comprises about 75 to about 95% by weight of magnesium chloride relative to the total amount of magnesium chloride and magnesium sulphate.
11. A stabilising composition of any one of claims 2 to 9 wherein the composition comprises about 5 to about 25% by weight of magnesium sulphate relative to the total amount of magnesium chloride and magnesium sulphate.
12. A stabilising composition of any one of claims 1 to 11 wherein the mixture comprises from about 32 to about 85% by weight magnesium chloride.
13. A stabilising composition of any one of claims 1 to 12 wherein the mixture comprises from about 5 to about 35% by weight magnesium sulphate.
14. A stabilising composition of any one of claims 1 to 13 wherein the composition comprises from about 5 to about 2 5% by weight hydrated calcium sulphate.
15. A stabilising composition of any one of claims 1 to 14 wherein the hydrated calcium sulphate is selected from one or more of gypsum (plaster of paris), lime or cement plaster.
16. A stabilising composition of any one of claims 1 to 15 comprising any one or more of - water resistant compound, - anti-corrosion agent, - an acid, or - any combination of any two or more thereof.
17. A stabilising composition of any one of claims 1 to16 comprising any one or more of - calcium sulphate, - 30 - portland cement, - sodium silicate, - lignosulphate, - organosilicon waterproofing agent, - a polymer compound, - silane, - a silicate, - bitumen, or - any combination of any two or more thereof.
18. A stabilising composition of any one of claims 1 to 17 comprising about 0.01 to about 2.1% by weight silicate.
19. A stabilising composition of any one of claims 1 to 18 comprising about 0.5 to about 10% by weight lignosulphate.
20. A stabilising composition of any one or more of claims 1 to 19 comprising a soil stabiliser binder.
21. A stabilising composition of any one or more of claims 1 to 20 comprising water.
22. A stabilising composition of any one or more of claims 1 to 21 comprising about 15 to about 60% water.
23. A stabilising composition of any one of claims 1 to 22 in the form of a powder, particle, granule or prill.
24. A stabilising composition of any one of claims 1 to 23 in the form of a wetted mixture, liquid or slurry.
25. A method of dust suppression and/or soil stabilisation comprising - obtaining a stabilising composition of any one of claims 1 to 24, - adding the stabilising composition to a substrate to be treated.
26. A method of dust suppression and/or soil stabilisation comprising - adding a stabilising composition of any one of claims 1 to 24 to a substrate to be treated to reduce the Plasticity Index of the treated substrate by at least 40%. - 31
27. A method of dust suppression and/or soil stabilisation comprising adding a stabilising composition of any one of claims 1 to 28 to a substrate to be treated increase the Californian Bearing ratio (CBR) of the substrate by at least about 50 to about 2000%.
28. A method of any one of claims 25 to 27 wherein the substrate is soil, road base, subgrade, sub-base or wear course.
29. A method of any claim 25 to 28 wherein the components of the composition are combined together with subsequent water addition to form a slurry.
30. A method of any claim 25 to 28 wherein the soluble components of the composition are first hydrated, and then the insoluble components are added to the hydrated soluble components.
31. A method of any one of claims 25 or 30 wherein the magnesium chloride and additive are blended prior to combining with magnesium oxide.
32. A method of one or more of claims 25 to3l wherein the magnesium chloride and magnesium sulphate are blended prior to combination with magnesium oxide.
33. A method of one or more of claims 25 to 32 wherein the blend is wetted prior to combining with the magnesium oxide.
34. A method of one or more of claims 25 to 33 wherein about 15 to about 60% by weight water is added to the stabilising composition mix.
35. A method of claim 25 or 30 wherein the composition is added to the soil to be treated for a purpose selected from one or more of - increasing the chemical stability of a soil, road base, subgrade, sub base or wear course, - increasing the strength of the road surface, - increasing the hygroscopic road surface, - increasing the useful life of a road bed, - increasing the strength of the road surface for re-grading and re healing, - providing a carbon dioxide sequestering system, - 32 - increasing the strength of a road surface that maintains its strength after prolonged exposure to environmental impact such as dry periods and persistent rains, - increasing the strength of a road surface or road base that maintains its superior strength and has the ability to hydrate and dry out soils with an exothermic reaction, - lowering the freezing point of the materials treated, and - increasing the build or construction process.
36. A method of any one of claims 25 to 35 wherein the moisture content of the treated soil, road base, subgrade, sub-base or wear course is between about 2 to about 10% by weight.
37. A method of any one of claims 25 to 36 wherein the composition of the invention increases the Californian Bearing ratio (CBR) of the substrate by at least 50, 100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700, 1800, 1900 or 2000%.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| NZ605203 | 2012-12-21 | ||
| NZ60520312 | 2012-12-21 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| AU2013273765A1 true AU2013273765A1 (en) | 2014-07-10 |
Family
ID=51228864
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| AU2013273765A Abandoned AU2013273765A1 (en) | 2012-12-21 | 2013-12-20 | A Stabilising Composition |
Country Status (1)
| Country | Link |
|---|---|
| AU (1) | AU2013273765A1 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111960794A (en) * | 2020-07-23 | 2020-11-20 | 中建材创新科技研究院有限公司 | Water-resistant paper-surface gypsum board and preparation method thereof |
| CN112047682A (en) * | 2020-08-21 | 2020-12-08 | 浙江博世华环保科技有限公司 | Heavy metal solidification stabilizing agent and preparation method and application thereof |
| CN116285899A (en) * | 2023-02-13 | 2023-06-23 | 武汉轻工大学 | A kind of solid waste-based encrusted environmental protection dust suppressant and its application |
-
2013
- 2013-12-20 AU AU2013273765A patent/AU2013273765A1/en not_active Abandoned
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111960794A (en) * | 2020-07-23 | 2020-11-20 | 中建材创新科技研究院有限公司 | Water-resistant paper-surface gypsum board and preparation method thereof |
| CN112047682A (en) * | 2020-08-21 | 2020-12-08 | 浙江博世华环保科技有限公司 | Heavy metal solidification stabilizing agent and preparation method and application thereof |
| CN112047682B (en) * | 2020-08-21 | 2022-03-25 | 浙江博世华环保科技有限公司 | Heavy metal solidification stabilizing agent and preparation method and application thereof |
| CN116285899A (en) * | 2023-02-13 | 2023-06-23 | 武汉轻工大学 | A kind of solid waste-based encrusted environmental protection dust suppressant and its application |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US10913688B2 (en) | Flowable compositions and methods of utilizing and producing the same | |
| RU2503768C2 (en) | Method for stabilisation of soil or foundation | |
| JP2011038104A (en) | Chemical agent for improving engineering properties of soil | |
| CN105924124A (en) | Soil stabilizer for reinforcing roadbed base | |
| RU2492290C1 (en) | Method to construct motor roads and motor road design | |
| Wu et al. | Mechanistic performance evaluation of chemically and mechanically stabilized granular roadways | |
| RU2281356C1 (en) | Ground consolidation composition and method of its usage for road building | |
| WO2016130144A1 (en) | Stabilizing soil | |
| AU2013273765A1 (en) | A Stabilising Composition | |
| RU2551560C2 (en) | Road-building composite material | |
| KR101251440B1 (en) | A method for hardened pavement using improved soil | |
| CA2580734C (en) | Materials for travelled surfaces | |
| AU2005243604A1 (en) | Stabilising compositions and processes | |
| EP0467483A1 (en) | Method of making a fluid tight stone foundation | |
| Rossow | Fly ash facts for highway engineers | |
| JP5308967B2 (en) | Pavement structure and pavement construction method | |
| WO2007026977A1 (en) | Soil rock layer's composition, constructing method thereof and road construction method thereby | |
| RU2493325C1 (en) | Earth mixture | |
| US5096498A (en) | Construction material containing catalytic cracking catalyst particles | |
| AU2013213726A1 (en) | Road paving method | |
| EP4001377B1 (en) | A method of preparing a construction site and soil stabilizer | |
| Mathur et al. | Lime/cement stabilisation for soil and granular materials | |
| KR102806110B1 (en) | Soil paving composition with loess and soil pavement method using the same | |
| JP5711781B2 (en) | Permeable pavement and its construction method | |
| Rapulane | Modified Silica Fume Soil Stabilisation of Marginal-Road Subgrades |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MK1 | Application lapsed section 142(2)(a) - no request for examination in relevant period |