Classifications

• • C—CHEMISTRY; METALLURGY
  • C21—METALLURGY OF IRON
  • C21B—MANUFACTURE OF IRON OR STEEL
  • C21B3/00—General features in the manufacture of pig-iron
  • C21B3/04—Recovery of by-products, e.g. slag
  • C21B3/06—Treatment of liquid slag
• • C—CHEMISTRY; METALLURGY
  • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
  • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
  • C04B5/00—Treatment of  metallurgical  slag ; Artificial stone from molten  metallurgical  slag 
• • C—CHEMISTRY; METALLURGY
  • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
  • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
  • C04B7/00—Hydraulic cements
  • C04B7/36—Manufacture of hydraulic cements in general
  • C04B7/368—Obtaining spherical cement particles
• • C—CHEMISTRY; METALLURGY
  • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
  • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
  • C04B7/00—Hydraulic cements
  • C04B7/36—Manufacture of hydraulic cements in general
  • C04B7/43—Heat treatment, e.g. precalcining, burning, melting; Cooling
  • C04B7/44—Burning; Melting
  • C04B7/4484—Non-electric melting
• • C—CHEMISTRY; METALLURGY
  • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
  • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
  • C04B7/00—Hydraulic cements
  • C04B7/36—Manufacture of hydraulic cements in general
  • C04B7/48—Clinker treatment
• • C—CHEMISTRY; METALLURGY
  • C21—METALLURGY OF IRON
  • C21B—MANUFACTURE OF IRON OR STEEL
  • C21B2400/00—Treatment of slags originating from iron or steel processes
  • C21B2400/02—Physical or chemical treatment of slags
  • C21B2400/022—Methods of cooling or quenching molten slag
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
  • Y02W30/00—Technologies for solid waste management
  • Y02W30/50—Reuse, recycling or recovery technologies

Definitions

• the present invention relates to a spherical hydraulic substance for producing a high-strength molded article, and a method for producing the same.
• Conventional methods for producing hydraulic substances involve firing or melting the raw material at a high temperature, cooling it, and converting the obtained bulk or granular material into appropriate auxiliary raw material. It is a method of adding and pulverizing. As a result, the individual particles exhibit angular and irregular shapes.
• the water cement ratio is 30%. When a high-performance water reducing agent is used, the amount of water can be further reduced, but the water cement ratio is still limited to 25%.
• the hydraulic substance such as cementite down DOO generally C a 0, S i 0 2 , A 1 2 0 3, F e 2 0 a 1 or more principal components to raw materials were blended, milled and calcined to the It is manufactured by finely pulverizing with cleansing force and adding gypsum to cleansing force, so that not only the shape of the particles is angular but also a large amount of heat is required for firing. In particular, two pulverizations require a large amount of power.
• a high-speed impact device in a gas stream is used to disperse the particle surface as disclosed in Japanese Patent Application Laid-Open No. 2-192439.
• a method of smoothing into a sphere but in this method, it is necessary to calcine the cleaning force of the hydraulic substance, and the degree of spheroidization and the surface smoothness are insufficient.
• the heat consumption and power consumption required for the conventional cement manufacturing method it is necessary to further add power consumption for applying a rotational impact to the fine particle material. Disclosure of the invention
• An object of the present invention is to solve the above-mentioned drawbacks of the prior art, and to provide a spheroidized hydraulic substance having a higher degree of perfection, and a method for producing the same.
• Spherical hydraulic material of the present invention for achieving the above described problems is the hydraulic powder and C a 0, S i 0 2 , A 1 2 0 3 and F e 2 0 3 the main components, at least of the powder Both are cooled after the surface is melted, and the powder has a particle diameter of 500 m or less and an average circularity of less than 500 m. It is characterized by being 0.7 or more.
• the manufacturing method of the first spherical hydraulic material of the present invention for achieving the above-mentioned problems, and C a O, S i 0 2 , A 1 2 0 3 and F e 2 0 a main component It is characterized in that a raw material is melted, the melt is scattered, and cooled and solidified in a scattered state.
• the third method for producing a spherical hydraulic substance to achieve the above-mentioned task is to focus on the utilization of the retained heat of a high-temperature substance such as a steelmaking slag at a temperature of 500 ° C or higher in the molten state. or 5 to 0 0 hot substance such as more steel scan lag in, C a O, S i 0 2, a 1 2 0 3, F e 2 0 3 dried product of raw material mainly composed of one or more , A calcined product, a sintered product or a molten material are mixed to form a mixed molten material, and the mixed molten material is scattered and cooled and solidified in a scattered state.
• a high-temperature substance such as a steelmaking slag at a temperature of 500 ° C or higher in the molten state. or 5 to 0 0 hot substance such as more steel scan lag in, C a O, S i 0 2, a 1 2 0 3, F e 2
• hydraulic substance to the S i 0 2, A 1 2 ⁇ 3 and F e 2 0 3 as a main component has a particle size in earthenware pots yo described above 5 0 0 m or less, the particles A spherical hydraulic substance characterized in that the average circularity is 0.70 or more.
• the circularity of a particle is represented by the ratio of the perimeter of a circle having the same projected area to the length of the contour of a projection view observed by a scanning electron microscope.
• the average circularity is the average value of the circularity of 50 randomly selected particles.
• the spherical hydraulic substance of the present invention has a particle size of 500 ⁇ m or less, preferably 100 im or less, and particles having a particle size of more than 500 JLL m have low strength after hardening. If the average circularity is less than 0.7, the fluidity of the paste, malt, and concrete is insufficient, and is desirably 0.9 or more.
• the spherical hydraulic substance of the present invention can be formed into spherical fine particles having a particle size of 3 / X m or less, and these spherical fine particles are used in spherical particles such as silica fume used for high-strength concrete.
• spherical particles such as silica fume used for high-strength concrete.
• the cross-linked material with water produces high strength, reduced drying shrinkage, and high durability by improving the fluidity and achieving the close-packed structure.
• an appropriate particle size is selected and used for a cast product using a dispersing agent, not only will a high strength comparable to an oxide ceramic molded product obtained by sintering be exhibited, but also the sintering process after casting will occur. Since it is not necessary, it is possible to obtain a molded product with better dimensional accuracy than an oxide ceramic sintered product.
• the fluidity of the kneaded material is improved even when kneading with the same amount of water.
• the amount of water when obtaining the same fluidity is significantly lower.
• because of its spherical shape it has the property that it easily slides between particles and is easily packed densely by natural settling. These effects are exerted as the particle shape becomes closer to a true sphere. The smaller the average circularity, the lower the packing density, and the larger voids are likely to remain. If the average circularity is 0.7 or more, excellent physical properties not found in ordinary cement can be obtained.
• the particles of the present invention are close to true spheres and have a smooth surface and a small surface area per unit weight, the amount of adsorbent and occlusion of the admixture added to increase dispersibility is reduced. In addition, there is an advantage that the addition amount is small.
• various cements may be used in addition to gypsum in different forms, sulfate substances such as alkali sulfate and magnesium sulfate, or an aqueous solution containing these substances in advance.
• the spherical hydraulic substance of the present invention is a spherical fine particle having a smooth surface and almost a true sphere, the kneaded product with water has a higher fluidity and strength than the conventional cement. Remarkably excellent.
• the spherical hydraulic substance of the present invention can be obtained by melting a raw material containing the component constituting the same, scattering the melt, and then cooling the molten substance in a scattered state.
• the method and apparatus for melting and scattering are not particularly limited, and include a combustion gas method, a plasma method, an explosion method, etc., and an electric furnace, a gas furnace, an arc discharge furnace, a reflection furnace, and a pulverized coal-fired boiler.
• a melting machine such as a laser or a laser
• it is scattered into a decompression vessel, or while the melt is flowing out, it is scattered by high-pressure air, inert gas, water vapor, etc. It collides with the body or puts it in a high-speed rotating body to make it spherical by the centrifugal force.
• the hydraulic substance of the present invention becomes spherical due to surface tension, and the particle diameter becomes smaller as the viscosity becomes lower.
• Various fluxes are used as a thickener to reduce the particle size.
• Raw materials include limestone, clay, silica, slag, bauxite, iron, and other materials that are normally used as cement raw materials, as well as coal ash, various incineration ash, and sewage sludge ash.
• Quick lime, volcanic ash, red mud, etc. can be used in an appropriate combination, or hydraulic materials such as cement, cement clean, slag, etc. can be used alone or in combination.
• the particle size, particle size distribution, and crystallinity of spherical particles can be arbitrarily changed by changing the temperature, surface tension, viscosity, scattering, and cooling conditions of additives, melts, as well as the raw material composition.
• the performance of hydraulic substances It is easy to diversify. Since the spherical hydraulic substance according to the present invention is spheroidized by the surface tension of the melt, the viscosity of the melt has a large effect on the particle size, particle size distribution, and circularity of the cooled sphere.
• the viscosity of the melt can be controlled by the melting temperature, the oxidizing / reducing atmosphere during melting, the chemical composition of the raw materials, and the addition of flux.
• the gas atomization method uses the nozzle shape, particle concentration, charge amount, residence time, type of gas that scatters the particles, Appropriate dispersion and cooling conditions by selecting the degree of vacuum, temperature, and nozzle shape for pressure, temperature, volume, and decompression methods, and the number of revolutions, disk radius, charge amount of molten material, and drop position for centrifugation. Must be created.
• the above-mentioned manufacturing method is completely different from the current manufacturing method of cement using a kiln and a crusher, so the following innovative technical results can be obtained.
• a rotary kiln in order to granulate the cleaner, the amount of the liquid phase increases greatly during firing, causing a fusion phenomenon within the rotary kiln, or a temperature around 150 ° C.
• the method of the present invention uses all raw materials with a wide range of chemical compositions that can be melted be able to. Therefore, it is possible to arbitrarily set a wide range of combinations and composition ratios of hydraulic minerals such as clinker minerals, and the performance of hydraulic materials including those that have been difficult to produce in the past. Can be easily diversified.
• the process from melting to spheroidization has fewer moving parts and fewer monitoring items compared to the normal cement manufacturing process, so there are advantages in terms of maintenance and operation of the manufacturing equipment. Is also big. Furthermore, since the finishing and crushing process is not required, energy for crushing and transport can be saved, and the amount of dust to be treated can be reduced. In addition, since the bulk specific gravity of the powder is large, there is an advantage that the storage weight in the same volume is increased as compared with ordinary cement.
• the performance of the conventional cement is not only significantly improved, but also the oxide is improved.
• Industrial contributions are insignificant because hydraulic materials can be manufactured that also exhibit new properties similar to ceramics sintered products.
• the spherical hydraulic substance of the present invention can be obtained by melting at least the surface of the powder in a scattered state and cooling and solidifying the powder in a scattered state. You can.
• the method and apparatus used in this method are not particularly limited, and a plasma method, an arc discharge method, and the like can be used.
• the spherical hydraulic substance of the present invention may be in a molten state or at 500 ° C.
• High temperature materials such as more steel slag, C a O, S i 0 2, A 1 2 0 3, F e 2 0 3 dry matter of the raw materials as a main component one or more, calcine, sinter
• it can also be obtained by mixing a melt to form a mixed melt, scattering the mixed melt, and cooling and solidifying in a scattered state.
• high-temperature materials such as steelmaking slag used are blast furnace slag, steelmaking furnace slag, lime ash, sewage sludge ash, various refuse incineration ash, rice husk ash, magma, lava, etc. These can be used in the molten state, so that their retained heat can be used.
• C a O, S i 0 2, A 1 2 0 3, F e 2 is a raw material mainly composed of upper 1 or more kinds of Q 3, limestone, lime, clay, stone silicofluoride, Bokisai bets, Iron ore, copper, and fluorite are mixed in consideration of the composition of high-temperature substances such as iron-made slag and the clean power to be manufactured.
• the compounding material is dried, calcined, sintered, or melted. In the molten state or mixed with high-temperature substances such as iron slag at 500 ° C or higher.
• a molten mixture of a high-temperature substance such as steelmaking slag and a compounded raw material is scattered, and cooled and solidified in a scattered state to form particles having a particle diameter of 500 m or less and an average circularity of 0.7 or more. I do.
• the melting and scattering methods and devices are not particularly limited.
• FIG. 1 is a photomicrograph of the polished surface of the spherical hydraulic substance of the present invention obtained in Example 2 at a magnification of about 500 ⁇ .
• the resulting spherical hydraulic substance contains many rounded alites having a particle size of 15 im or less and belites having a particle size of 10 m or less, which are smaller than ordinary clean minerals.
• the resulting spherical hydraulic substance contains many rounded alites having a particle size of 15 im or less and belites having a particle size of 10 m or less, which are smaller than ordinary clean minerals.
• no clear difference was observed in the particle size and composition ratio of the mineral between the central part and the surface part of the spherical particle, and the whole particle had a homogeneous mineral and chemical composition.
• a paste was prepared from this cement using a high condensate of formalin naphthalenesulfonate (Mighty 150, manufactured by Kao Corporation) as a water reducing agent.
• the paste was hand-kneaded, and the test cement (400 g) was weighed in a mortar specified in JISR 5201.Then, the aqueous solution of Mighty 150 was added to Mighty 150. The amount was 2.0% of the cement, and finally the remaining amount of water was added to adjust the softness of the paste. The softness of the paste was adjusted to the standard softness of the setting test.
• Specimens of 2 x 2 x l2 cm were prepared with the kneaded paste, and after demolding, a strength test in water for 28 days at room temperature and a strength test after autocure were performed.
• the conditions for autoclaving are 179 ° C and 6 hours.
• Table 1 shows the strength test values of Examples 1 and 2 and Comparative Examples 1 and 2.
• test cement using the spherical hydraulic substance has a smaller standard soft water volume than the ordinary portland and has a large water reducing effect. Also, the strength is much higher in the test cement. Those with 0.84 (Example 1) and 0.92 (Example 2) show better physical properties than those with an average circularity of 0.63 (Comparative Example 1).
• a plasma frame is generated while supplying 65 liters of argon and 10 liters of nitrogen into the torch of a high-frequency plasma generator with a frequency of about 4 MHz and a high-frequency output of 50 kW continuously.
• Portland cement clinker powder with a particle size of about 40 to 100 ⁇ m was passed through the plasma frame at a feed rate of about 1 minute, and cooled in the lower hopper. Collect the spherical particles was. True spherical particles having an average particle size of about 70 ix m were obtained.
• FIG. 1 shows a microscopic photograph of a polished surface of the obtained spherical particles at a magnification of about 500 times. Dendritic or acicular silicate phase minerals are formed in the particles that are entirely melted, and dendritic or acicular silicate phase minerals are formed in the surface layer of particles that melt only in the surface layer. On the inside, normal silicate phase minerals, which were included in the original Clinic force, were observed.
• test cement using spherical particles has a lower standard soft water volume and a greater water-reducing effect than the comparative cement in which the fine powder of gypsum dihydrate was added to the original clean force by 3% by weight. . Also, the strength is much higher in the test cement.
• test cement was prepared by adding 3% by weight of fine gypsum dihydrate to the original clinker particles (Comparative Example 4) and the spherical particles.
• a cement paste was prepared by using a high condensate of formalin naphthalene sulfonic acid (Mighty 150, manufactured by Kao Corporation) as a water reducing agent for these cements.
• the paste was hand-lined, and the test cement (400 g) was weighed in a mortar specified in JISR5201, and then an aqueous solution of Mighty 150 was added.
• the amount of water was adjusted to 2.3% of the cement, and finally the remaining amount of water was added to adjust the softness of the cement paste. The softness was adjusted to the standard softness of the setting test.
• test cement composed of spherical particles has a smaller standard soft water volume than the cement with the above-mentioned clean power powder used for comparison, and has good strength expression. Therefore, it is possible to produce a paste, mortar or concrete having a low flow rate and high fluidity and high strength.
• the blast-furnace slag which was melted at 1450, was placed in a gasifier using oxygen-enriched air, and heated to 1900 while gradually mixing lime, silica, copper, and fluorite in it. Upon melting, it usually became the main chemical composition of Portland cement cleanliness.
• the mixed melt is received in a high-frequency melting furnace of a gas atomizer, and the melt is discharged from the melting furnace and blown with air at a pressure of 6 MPa to atomize the melt, and has an average particle size of about 30 m and an average circular shape.
• the spherical clean particles having a degree of 0.97 were obtained.
• Example 5 To the obtained spherical particles, 3% by weight of a fine powder of gypsum dihydrate was added to prepare a test cement, which was adjusted to the standard softening water amount for the coagulation test specified in JISR521. A specimen having a diameter of 5 cm and a length of 10 cm was prepared by kneading the paste, and after demolding, the specimen was cured in water at 20 ° C and subjected to a compressive strength test. As Comparative Example 5, the same cleanliness particles having the same composition and the same average particle size as those of Example 5 were produced in the same manner as in Example 5 by the conventional cement production method.
• test cement using the particles according to the examples has a smaller standard soft water volume, a greater water-reducing effect, and is superior in strength development than the cement according to the comparative example.

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• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Ceramic Engineering (AREA)
• Materials Engineering (AREA)
• Organic Chemistry (AREA)
• Structural Engineering (AREA)
• Physics & Mathematics (AREA)
• Thermal Sciences (AREA)
• Manufacturing & Machinery (AREA)
• Metallurgy (AREA)
• Curing Cements, Concrete, And Artificial Stone (AREA)
• Ceramic Products (AREA)
• Compositions Of Oxide Ceramics (AREA)
• Glanulating (AREA)

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• 1991
  • 1991-11-01 CA CA 2073170 patent/CA2073170A1/en not_active Abandoned
  • 1991-11-01 DE DE69120257T patent/DE69120257T2/de not_active Expired - Lifetime
  • 1991-11-01 EP EP91918995A patent/EP0513367B1/en not_active Expired - Lifetime
  • 1991-11-01 WO PCT/JP1991/001497 patent/WO1992007803A1/ja not_active Ceased
  • 1991-11-01 JP JP51722891A patent/JP3176919B2/ja not_active Expired - Fee Related
• 1992
  • 1992-07-03 NO NO92922647A patent/NO922647L/no unknown

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