TWI309674B - Sealing composition and its use - Google Patents

Description

1309674 A7 ___B7______ V. INSTRUCTIONS (/) The present invention relates to the use of a composition for sealing rock and soil. The invention also relates to a method for shutting off the flow of liquid in a leaky portion or cavity. The invention also relates to a method of preparing the sealing composition and a sealing composition obtainable by the method. BACKGROUND OF THE INVENTION The requirements and performance of compositions for sealing rock and soil have increased. These requirements are accompanied by improvements in both environmental and technical aspects. Previously, various plastics and polymers containing toxic substances have been used to seal leaks in, for example, concrete walls, underpasses, or voids formed on the back of concrete walls. This sealing chemistry has caused groundwater contamination in many instances and poses health problems for construction workers such as those handling chemicals. However, attempts have been made to replace harmful products with products that are more suitable for the environment. Novel products are also sought to meet recent mandatory leakage limits. In some cases, a water leak of less than 1 liter / (minute * 100 meters) is the upper limit of the construction site at the underpass. This has forced contractors to provide technologically improved sealing products. No. 5,396,749 describes a method of shutting off water flow by grouting, thus avoiding the trouble of water leakage and collapse of the substrate. The flow-off agent is prepared by mixing, for example, colloidal ceria, an inorganic salt, and a water-soluble urethane polymer. However, the strength of these agents has been insufficient in many applications, particularly when exposed to high water pressure during injection and gelation. In particular, unstable reagents have a relatively low long-term strength during the aging phase. Sealants have also been used to seal soils to avoid leakage of contaminants in the masked areas of buried sources, waste piles, and the like. U.S. Patent No. 5,836,390 describes the formation of a paper size of 3 for the Chinese National Standard (CNS) ^ (21 ° x 2 耵 mm) <Please read the back note 杳 ί and then fill in this I)

1309674 A7 —---~______B7__ V. The method of the invention (>) is to inject a viscous liquid containing a shed such as a sputum, a polyxanthine, and a dioxin (4). θ A liquid intercepting agent with a high long-term strength suitable for the environment: t', especially in the field of sealed rock, where the cut-off = can be subject to high water pressure from groundwater. It is also desirable to provide a durable product that is resistant to scouring and has a low water or other liquid. It is intended to provide such products that address the aforementioned prior art disadvantages. The present invention relates to the use of a sealing composition for sealing rock or soil. The sealing composition can be obtained by mixing a cerium sol having at least about 72% S 和 and at least one gelling agent. The invention also relates to a method for shutting off a liquid stream in a leaky portion or cavity, which will be obtained by mixing a cerium sol having at least about 72% S 和 and at least one gelling agent. The sealing composition is inserted into the leaky portion or cavity. The invention also relates to a method of making a sealing composition comprising mixing a cerium sol having greater than about 72% S 和 and at least one gelling agent. The invention also relates to a sealing composition obtainable by this method. It has been unexpectedly found that having a high S値' is higher than about 72°/. The sol can impart a high long-term gel strength to the sealing composition. The term “gel strength” as used herein refers to the gelatinous seal composition produced over time. 4 This paper scale applies to the Chinese National Standard (CNS) A4 specification (210 X 297 mm). (Please read the phonetic transcription on the back first. ? 再 填写 填写 ) ) 130 130 130 130 967 967 967 967 967 967 967 967 967 967 967 967 967 967 967 967 967 967 967 967 967 967 967 967 967 967 967 967 967 130 130 130 130 High long-term strength provides a durable seal. It has also been found that the sealing composition of the present invention has low permeability which exhibits good sealing characteristics. "s値" means the degree of aggregation of cerium oxide particles in the cerium sol, that is, the degree of aggregation or formation of microgels. The S値 of the cerium sol is measured and calculated according to the formula published in Iler, R.K. & Dalton, R.L., J. Phys. Chem. 60 (1956), 955-957. S値 depends on the cerium oxide content, viscosity and density of the cerium sol. A high S 値 shows a low microgel content. S値 represents the weight percentage of the amount of Si〇2 present in the dispersed phase of the sol. As described further in, for example, us 5368833, the degree of microgel can be controlled during the production process of the cerium sol. According to a preferred embodiment of the invention, the S is more than about 73%, preferably more than about 74%, more preferably more than about 75%. Preferably, the S system is less than about 90%, and most preferably less than about 85%. The cerium sol contains cerium oxide particles suitably having an average particle diameter ranging from about 3 to about 150 nm, preferably from about 12 to about 50 nm, and most preferably from about 12 to about 40 nm. Suitably, the cerium oxide particles have a specific surface area of from about 20 to about 900, preferably from about 40 to about 230, and most preferably from about 60 to about 220 mbar / gram. The density of the cerium sol is suitably from about 1 to about 1.6, preferably from about Μ to about 1.5 and most preferably from about 1.2 to about 1.4 kg/m3. The cerium sol is substantially suitable for monodisperse, i.e., has as narrow a particle size distribution as possible. Suitably, the silica sand particle system has less than about 15% by number. 5 The paper scale is applicable to the Chinese national standard (CNS>A4 specification (210 X 297 mm) (please read the back note before filling this page), binding ----------

1309674 V. Inventive Note (f), preferably a relative standard deviation of particle size distributions below about 10% by number and optimally below about 8% by number. The relative standard deviation of the particle size distribution is the ratio between the average particle size in number and the standard deviation of the particle size distribution. The cerium oxide particles of the cerium sol are suitably dispersed in water in the presence of a stable cation such as K+, :Na+, Li+, NH4+ or the like or a mixture thereof. However, other dispersions may be used, such as organic solvents, such as lower alcohols, acetone or mixtures thereof. The pH of the dispersion is suitably from about 1 to about I2, preferably from about 7 to about 11. As long as the cerium sol remains stable, i.e., without any aggregation or gelation, the cerium sol has a high content of sulphur dioxide. It is advantageous from the viewpoint of the excellent technical properties of the highly concentrated cerium sol and its reduced transportation cost. According to a specific example, the ingredients, i.e., the enamel sol and the gelling agent, are respectively applied to the application point to be sealed. It can be done, for example, in so-called jet grouting, where the ingredients are in situ, for example in soil. The term "tantalum sol" and "cerium oxide particles" as used herein also means, for example, cerium oxide particles and chopped sol modified by bromine, and cerium oxide particles modified by boron and cerium sol. Boron-modified cerium sols are described, for example, in U.S. Patent 2,630,410. An aluminum-modified cerium sol can be prepared by adding an appropriate amount of aluminate ions, Al(〇H)4-, to a conventional unmodified cerium sol under agitation and heating, sometimes also as an aluminum. Acid-modified sand sol. Suitably 'using a dilute sodium aluminate or potassium aluminate solution, which is modified from about 0.05 to about 2', preferably from about 0.1 to about 2 aluminum atoms per nanometer of cerium oxide particle surface area. Things. The aluminum-modified silica sand particles contain inserted or exchanged aluminate ions to produce 6 with a fixed negative surface charge. This paper scale applies to the Chinese National Standard (CNS) A4 specification (210 X 297 mm) (please read first) Note on the back side of this page) -1------Book-----I--- 1309674 A7 _____B7___ V. Description of the invention (ζ) Aluminate. The pH of the aluminum-modified cerium sol can be adjusted to a pH ranging from about 3 to about 11, preferably from about 4 to about 10, which is preferably adjusted with an ion exchange resin. The aluminum-modified ceria particles suitably have an A1203 content of from about 0.05 to about 3% by weight, preferably from about 0.1 to about 2% by weight. The step of preparing an aluminum-modified cerium sol is further described, for example, in "The Chemistry of Silica" by Iler, K. Ralph, pp. 407-409, John Wiley & Sons (1979) and US 5 368 833. The coagulant is suitably an inorganic salt or an acid, an organic salt such as sodium acetate, or an organic acid such as acetic acid; but preferably an inorganic salt such as potassium chloride, calcium chloride, sodium chloride, magnesium chloride or magnesium sulfate. And potassium iodide, magnesium nitrate, sodium nitrate, potassium nitrate, calcium nitrate and sodium citrate, or a mixture thereof, preferably calcium chloride, sodium chloride or potassium chloride, and most preferably sodium chloride or sodium aluminate. Gel time modifiers such as acid triacetin (triacetin), diacetin 'Glauber's salt (NaSO4*10H2O), sulfuric acid, phosphoric acid or mixtures thereof may also be used. , added to the sealing composition to control its gelation. The term "gelling time" as used herein refers to the total time elapsed from the moment when the components constituting the sealing composition are mixed until the sealing composition becomes too viscous to move or insert a leak. . The viscosity is suitably controlled so that the uniform moving front end of the composition is formed in the moving direction of the point to be sealed. Suitably, the sealing composition has an initial viscosity of from about 3 to about 100, preferably from about 4 to about 30 mPas. This gel time can be easily controlled by adjusting the amount of gelling agent. In some cases, in order to provide gelation, the paper size is applicable to the Chinese National Standard (CNS) A4 specification (210 X 297 mm) " (Please read the note on the back and fill out this page) ---- ----Book --------

A7 1309674 ___B7^__ V. INSTRUCTIONS (^) Anti-pressure seal composition is required for the instant gelation without substantial dilution of the composition. Short gel times may be optimal when the cracks are quite comminuted and when there is a risk of rapid dilution of the seal composition. In some instances, it is especially necessary that the crack should not begin to gel before the front end of the insert composition has completely penetrated the crack. Typically, in rock seals, the gel time ranges from about 1 to about 120, preferably from about 2 to about 60, more preferably from about 5 to about 40 and most preferably from about 5 to about 20 minutes. In soil sealing, the gel time typically ranges from about 5 minutes to about 24 hours, preferably from about 10 minutes to about 6 hours and most preferably from about 15 minutes to about 3 hours. The ingredients can be mixed at ambient temperature. The gelling agent is suitably added to a concentration of from about 1 to about 30% by weight, preferably from about 2 to about 15% by weight, of the aqueous solution of the sand sol. A cerium sol in which a gelling agent has been suitably added, suitably having a cerium oxide content of from about 1 to about 70, preferably from about 20 to about 60 and most preferably from about 35 to about 50% by weight. The high cerium oxide content in the cerium sol is advantageous in many instances due to the reduced transportation cost of the cerium sol. The cerium oxide content in the sealing composition is suitably from about 1 to about 6 Torr, preferably from about 15 to about 50 and most preferably from about 30 to about 45% by weight. The high cerium oxide content reduces shrinkage and increases long-term strength. The weight ratio of cerium oxide to gelling agent depends on the application and can vary depending on the application. Suitably, the weight ratio of cerium oxide particles: gelling agent is from about 4 Å:1 to about 10:1, preferably from about 200:1 to about 20:1. The amount of gelling agent in the sealing composition may be in the form of the gelling agent used. 8 (Please read the notes on the back and fill out this page)

This paper scale applies to China National Standard (CNS) A4 specification (210 X 297 public meals) A7 1309674 V. Invention description (j) (Please read the note on the back and fill out this page) and change. However, the gelling agent is suitably present in an amount of from about ο1 to about ίο, preferably from about 〇2 to about 5% by weight of the composition. If sodium chloride is used as the gelling agent, the amount is suitably from about 0.2 to about 5, preferably from about 1 to about 3, and most preferably from about 1.5 to about 2, of the composition. The weight % ° if calcium chloride is used as the gelling agent', the content is suitably from about 0.1 to about 2, preferably from about 0.2 to about 1, and most preferably from about 0.25 to about 2,000. 0.5% by weight. According to a preferred embodiment, the sealing composition is inserted by separately injecting the cerium sol into the leaking portion or the cavity, thereby forming a sealing composition in the original position, for example, in a crack of the rock or a cavity in the soil. Therefore, the gelling agent can also be separately injected into the leaking portion or cavity. It can be accomplished, for example, by simultaneous injection of the sealing component, such as via placing the enamel sol and the injection nozzle for the gelling agent in parallel such that the gelling agent and the cerium sol can be injected simultaneously without premixing. However, 'in a particular leaky portion or cavity, for example in the soil, for example, a gelling agent in the form of a salt may already be present in the soil in a specific amount' so that no further addition of the gelling agent is required to form Seal the composition. Therefore, in a preferred embodiment of the invention, only the cerium sol is injected separately into the leaking portion or voids. The process can generally be applied to shut off any liquid streams, such as water and aqueous solutions, organic solutions, and the like, but the process is primarily suitable for shutting off water and aqueous streams. Alternatively, other methods such as jet grouting may be used to remove the leaking portion of the sealing composition insert or the material of the cavity to join the sealing composition, and then apply the sealing composition in the material from the previous The removed points are re-embedded to the same point. This method is applicable to the Chinese National Standard (CNS) A4 specification (210 X 297 public) 1309674 A7 ______B7________ V. Inventive Note (f) It is preferably suitable for use in soil sealing. According to a preferred embodiment, the bismuth solute and the gelling agent are mixed immediately prior to injection. In this connection, the phrase "instant" means from about 〇 to about 30 seconds, preferably from about 0 to about I5 seconds. This method of mixing constituent components is often referred to as in-line mixing. According to a preferred embodiment, the sealing composition can also be prepared in advance in a batch process and suitably used within 60 minutes and preferably within 30 minutes prior to insertion of the composition. However, this method of preparing the sealing composition requires a very stable sealing composition which can be stored until there is no significant gelation at the time of insertion. The injection time of the sealing composition is suitably from about 1 minute to about 1 hour, preferably from about 5 minutes to about 30 minutes. The depth of injection/penetration will of course vary with the leakage to be sealed. However, the process of the present invention is particularly advantageous for a depth of from about 0.5 to about 50 meters, preferably from about 5 to about 30 meters. The injection pressure is suitably from about 1 to about 50 bar, preferably from about 2 to about 25 bar. The sealing composition is primarily suitable for providing a subsurface barrier to avoid water leakage. The sealing of the rock is accompanied by the insertion of the sealing composition into, for example, voids, such as micro-cracks, especially to control groundwater seepage, such as in an underpass. The term "fine crack" generally refers to a cavity having a diameter of less than 20 microns. When the diameter of the cerium oxide particles in the cerium sol is from about 1 Torr to about 100 nm, the sealing composition containing the cerium oxide particles is of course suitable for injection into the fine cracks. The invention thus being described, it will be apparent that the invention may be modified in many aspects. Such changes are not to be regarded as a departure from the gist and scope of the present invention. 10 ί Paper scale applies to the Chinese National Standard (CNS) A4 specification (210 >< 297 mm) "" (Please read the notes on the back first) Fill in this page again) Install 1§J·

1309674 A7 __B7 a ' ----- V. Description of invention ()

I, and all such modifications apparent to those skilled in the art should be included in the scope of the patent application. The following examples will further illustrate how to complete the described invention without limiting its scope. Example 1 A sealing composition was prepared by adding a salt solution of 1.7 Μ sodium chloride to 200 g of a different cerium sol product as defined in the following table under agitation. The amount of the salt solution added to all the compositions was 40 g of the solution. The composition was aged until 672 hours to evaluate the long-term shear strength. In Table 1, a set of compositions was exposed to an elevated temperature of 55 ° C and another set was exposed to pH 12 to accelerate the aging of the seal composition. The particle diameter of the silica sand particles was calculated by the Sear's method for calculating the specific surface area. The shear strength test was carried out according to the Swedish standard SS 02 71 25 with a concrete cone cone test. The extrusion strength of the sealing composition was also measured. It is accomplished by a squeeze test in which a load base is used, a pressure probe having the same diameter as the sample, and a load cell having a flat surface, wherein the sample is placed between the load cell and the pressure probe. Displacement converter, battery-powered data recording device, signal processing software. The load base forces the pressure probe to move in a vertical direction. The base is the same form as the base used to control vertical drilling in a mechanical workshop. The load is controlled via weight, which loads the load probe without any transmission (static weight). The pressure probe consists of a solid steel cylinder with a diameter of 50 mm. The load cell has a capacity of 300 kg. The load cell forms a flat surface. The sample is located in the load cell and the pressure is 11 The paper size is applicable to the Chinese National Standard (CNS) A4 specification (210 X 297 mm) (please read the back note before completing this page) ·ΙΙΙ — — — —

1309674 A7 V. INSTRUCTIONS (/D) Between the probes. The accuracy of the load cell is within ο.1 kg. The displacement converter has a stroke volume of 5 mm. The actual converter error was tested by the manufacturer to a maximum of 0.4%. The data recording device used in the test was developed to monitor vibration and deformation during field conditions. The recording device was continuously monitored during the test. The extrusion test was performed only on samples that were cured during 28 days. The molding cylinder is 50 mm in diameter and 25 mm in height. The molding cylinder is located in a pan having a flat bottom surface. The sealing composition is then poured into the upper end of the barrel. All samples were cured at pH 10 (TC water bath. Only cross sections were exposed to water. Samples were separated from the molding cylinder prior to testing. Table 1 Composition particle diameters prepared with the following sols (nano) S-表面积 Surface area by product (m 2 / gram) Shear strength (kPa) 55, pH 10, 672 hours Shear strength (kPa) 20 ° C, pH 12, 672 hours _ sol 1 17 77 68 326 Sol 2 12 76 S8 640 475 Sol 3 11 70 ]〇0 218 Sol 4 7 70 108 250 70 _mm 5 5 45 Ί5 48 39 In Table 1, it can be seen at ambient temperature and pH 12 (which accelerates the aging of the product) And at a pH of 10 and a temperature of 55 ° C (which also causes a faster aging method), the sealing composition made of the bismuth sol having the S 本 of the present invention has a comparative 矽 sol 3- after 672 hours 5 The gel strength of the prepared composition is high. ___ 12 Ben. 'Da Zhang scale standard Zhongguan standard (CNS) A4 specifications (21〇X 297 public) (Please read the back of the note before you fill out this page )--------Book----------

Composition particle diameter (nano) S-値 made by the following sols Surface area by product (m 2 /g) Extrusion strength (kPa) / maximum load mm 6 35 90 40 48 Sol 1 17 77 68 50 Sol 2 12 76 88 45 Sol 3 11 70 100 11 Sol 5 5 45 75 11 In Table 2, it can be seen that the sealing composition prepared from the cerium sol having the S 本 of the present invention is compared with the comparative sols 3 and 5 The resulting sealing composition imparts a high extrusion strength. 1309674 A7 _B7 V. INSTRUCTIONS (//) TABLE 2 This paper scale applies the Chinese National Standard (CNS) A4 specification (210 X 297 mm) (please read the back note 咅3 and then fill out this page)

Claims (1)

j FR 09674:^ VI. APPLICATION Scope I 1. Use of a sealing composition for sealing rock or soil 'where the sealing composition can be mixed with a cerium sol having at least about 72% S 和 and at least A gelling agent is obtained. 2. A method of cutting a liquid stream in a leaky portion or cavity by inserting a sealing composition, the sealing composition being capable of mixing a cerium sol having at least about 72% S 和 and at least one Obtained with a gelling agent. A method of preparing a sealing composition by mixing a cerium sol having more than about 72% S 和 and at least one gelling agent. 4. The method of claim 3, wherein the cerium sol and the gelling agent are injected into the leaking portion or cavity by individually injecting the cerium sol into the leaking portion or cavity Mix ground. 5. A sealing composition obtainable by mixing a cerium sol having greater than about 72% S' hydrazine and at least one gelling agent. 6. The use of item 1 of the scope of the patent application wherein the s 値 is greater than about 75% ° 7. The use of the bismuth sol is an aluminum-modified cerium sol, as claimed in claim 1. 8. The use of claim 1 wherein the composition has a cerium oxide content of from about 35 to about 50% by weight. 9. The use of claim 1, wherein the gelling agent is selected from the group consisting of potassium chloride, sodium chloride, calcium chloride, magnesium chloride, magnesium nitrate, magnesium sulfate or a mixture thereof. 10. The use of claim 1, wherein the composition has a relative standard deviation of particle size distributions of less than about 15%. This paper size applies to the Chinese National Standard (CNS) A4 specification (21〇 X 297 public) (please read the notes on the back and fill out this page) 1309674 韶 C8 D8 VI. Scope of Application I I1. The use of claim 1, wherein the composition has a gelling agent content of from about 0.2 to about 5% by weight. 12. The use of claim 1, wherein the cerium sol comprises cerium oxide particles having a specific surface area of from about 40 to about 230 m 2 /g. 13. The use of the first aspect of the patent application, wherein The composition has a weight ratio of cerium oxide particles to gelling agent of from about 400:1 to about 1 :1. 14. The use of claim 1, wherein the composition comprises cerium oxide particles having a size ranging from about 12 to about 50 nanometers. 15. The method of claim 2, wherein the S is greater than about 75%. 16. The method of claim 2, wherein the cerium sol is an aluminum modified cerium sol. 17. The method of claim 2, wherein the composition has a cerium oxide content of from about 35' to about 50% by weight. 18. The method of claim 2, wherein the gelling agent is selected from the group consisting of potassium chloride, sodium chloride, calcium chloride, magnesium chloride, magnesium nitrate, magnesium sulfate or a mixture thereof. 19. The method of claim 2, wherein the composition has a relative standard deviation of particle size distributions of less than about 15%. 20. The method of claim 2, wherein the composition has a gelling agent content of from about 0.2 to about 5% by weight. 21. The method of claim 2, wherein the bismuth sol comprises 2 paper sizes applicable to the Chinese National Standard (CNS) A4 specification (210 X 297 mm) ------------ ------------------ (Please read the note on the back and write this page first) Order: A8B8C8D8 ί· 1309674 VI. Apply for Patent Fan Park I has about 4〇 A cerium oxide particle having a specific surface area of about 230 m 2 /g. 22. The method of claim 2, wherein the composition has a cerium oxide particle of from about 400:1 to about 1 :1 The weight ratio of the coagulant. 23. The method of claim 2, wherein the composition comprises cerium oxide particles having a size ranging from about 12 to about 50 nanometers. 24. The sealing composition of claim 5, wherein the S 高于 is greater than about 75%. 25. The sealing composition of claim 5, wherein the bismuth sol is an aluminum modified sand sol. 26. The sealing composition of claim 5, wherein the composition has a cerium oxide content of from about 35 to about 50% by weight. 27. The sealing composition of claim 5, wherein the gelling agent is selected from the group consisting of potassium chloride, sodium chloride, calcium chloride, magnesium chloride, magnesium nitrate, magnesium sulfate or a mixture of cerium. 28. The sealing composition of claim 5, wherein the composition has a relative standard deviation of particle size distributions of less than about 15%. The sealing composition of claim 5, wherein the composition has a gelling agent content of from about 0.2 to about 5% by weight. The sealing composition of claim 5, wherein the cerium solute comprises cerium oxide particles having a specific surface area of from about 40 to about 230 m 2 /g. 31. The sealing composition of claim 5, wherein the composition 3^ paper scale is applicable to the Chinese National Standard (CNS) A4 specification (210 x 297 public interest) <Please read the back note and then write the book Page) *-° _ 1309674 C8 D8 VI. Patent Application I has a weight ratio of cerium oxide particles to gelling agent of from about 400:1 to about 10:1. (Please read the note on the back and write this page first) 32. The sealing composition of claim 5, wherein the composition comprises cerium oxide particles having a size ranging from about 12 to about 50 nanometers. . This paper scale applies to the Chinese National Standard (CNS) A4 specification (210 X 297 mm)