Classifications

• • 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
  • C04B40/00—Processes, in general, for influencing or modifying the properties of mortars, concrete or artificial stone compositions, e.g. their setting or hardening ability
  • C04B40/0028—Aspects relating to the mixing step of the mortar preparation
  • C04B40/0039—Premixtures of ingredients
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
  • B01J2/00—Processes or devices for granulating materials, e.g. fertilisers in general; Rendering particulate materials free flowing in general, e.g. making them hydrophobic
• • 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
  • C04B14/00—Use of inorganic materials as fillers, e.g. pigments, for mortars, concrete or artificial stone; Treatment of inorganic materials specially adapted to enhance their filling properties in mortars, concrete or artificial stone
  • C04B14/02—Granular materials, e.g. microballoons
  • C04B14/04—Silica-rich materials; Silicates
  • C04B14/10—Clay
  • C04B14/106—Kaolin
• • 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
  • C04B18/00—Use of agglomerated or waste materials or refuse as fillers for mortars, concrete or artificial stone; Treatment of agglomerated or waste materials or refuse, specially adapted to enhance their filling properties in mortars, concrete or artificial stone
  • C04B18/02—Agglomerated materials, e.g. artificial aggregates
  • C04B18/021—Agglomerated materials, e.g. artificial aggregates agglomerated by a mineral binder, e.g. cement
• • 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
  • C04B20/00—Use of materials as fillers for mortars, concrete or artificial stone according to more than one of groups C04B14/00 - C04B18/00 and characterised by shape or grain distribution; Treatment of materials according to more than one of the groups C04B14/00 - C04B18/00 specially adapted to enhance their filling properties in mortars, concrete or artificial stone; Expanding or defibrillating materials
  • C04B20/0016—Granular materials, e.g. microballoons
• • 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
  • C04B20/00—Use of materials as fillers for mortars, concrete or artificial stone according to more than one of groups C04B14/00 - C04B18/00 and characterised by shape or grain distribution; Treatment of materials according to more than one of the groups C04B14/00 - C04B18/00 specially adapted to enhance their filling properties in mortars, concrete or artificial stone; Expanding or defibrillating materials
  • C04B20/0076—Use of materials as fillers for mortars, concrete or artificial stone according to more than one of groups C04B14/00 - C04B18/00 and characterised by shape or grain distribution; Treatment of materials according to more than one of the groups C04B14/00 - C04B18/00 specially adapted to enhance their filling properties in mortars, concrete or artificial stone; Expanding or defibrillating materials characterised by the grain distribution
  • C04B20/008—Micro- or nanosized fillers, e.g. micronised fillers with particle size smaller than that of the hydraulic binder
• • 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
  • C04B7/38—Preparing or treating the raw materials individually or as batches, e.g. mixing with fuel
  • C04B7/40—Dehydrating; Forming, e.g. granulating
• • 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
  • C04B7/52—Grinding ; After-treatment of ground cement
  • C04B7/522—After-treatment of ground cement

Definitions

• the present invention relates to a structured, granular binder composition, which is suitable for manufacturing concrete mass, and to a concrete or mortar mass that contains the granular composition.
• the invention also relates to methods of manufacturing the granular composition and the concrete or mortar mass.
• Concrete is a material that consists of various ingredients and the properties of which are constantly changing. A great deal of factors affects the behaviour and the properties of concrete, such as changes in the moisture and temperature, the carbon dioxide content of the air, etc. There is a strong dependence between the changes in the moisture content of concrete and its mechanical properties, such as its strength, shrinkage, creep and the elastic modulus. Water, i.e., moisture, is also an essential part of old and hardened concrete.
• the active ingredient of concrete i.e., the hardened binder or cement stone
• the active ingredient of concrete i.e., the hardened binder or cement stone
• Such a porous and hygroscopic substance which has an enormous amount of inner surface area (about 200 nrVg), is sensitive to external influences and experiences continuous structural changes.
• the cement and the concrete made of it are substances which are difficult to define.
• the most general binders, such as cement have a common property that they are curable with water, and such binders are called hydraulic binders.
• the most typical of these hydraulic binders is Portland cement, the main components of which comprise tricalcium silicate (C 3 S in terms of cement chemistry, 54%), dicalcium silicate (C 2 S, 17%), tricalcium aluminate (C 3 A, 10%) and tetracalcium aluminoferrite (C 4 AF, 10%).
• C 3 S tricalcium silicate
• C 2 S dicalcium silicate
• C 3 A tricalcium aluminate
• C 4 AF tetracalcium aluminoferrite
• C 3 S When hydrating, C 3 S releases 3 moles OfCa(OH) 2 and C 2 S releases one mole of calcium hydroxide, respectively.
• the fastest to harden is C 3 A, which requires 6 moles of water for the hydration, as well as C 4 AF.
• the compression strength of the binder mainly develops from the hydration of C 3 S and, in the long run (>90 days), from the hydration of C 2 S, by which the same end result is obtained as by the hydration product of C 3 S, finally, within the same time, in about a year, at normal temperature.
• a theoretical ratio of water and cement (the w/c ratio), wherein all of the water would be consumed by hydration, would be 0.245 at the composition described above.
• the pozzolanic reaction is a reaction of calcium hydroxide [(CH) in terms of cement chemistry], silica, SiO 2 (S) and water (H), wherein a CSH compound as well as CAH and CASH compounds are formed, depending on the pozzolanic material.
• metakaolin When kaolin is heat-treated at a temperature of 500-850 C°, it loses its crystal water and Al 2 O 3 • SiO 2 , which is pozzolanically active in water, is obtained.
• the product is called metakaolin.
• metakaolin Various companies sell metakaolin and research shows that it is more effective in improving the strength than microsilica whilst, at the same time, being more effective in compacting the concrete, etc.
• a third way of accomplishing bond strength in a mineral binder is to allow small particles to combine into larger ones through crystallisation.
• the core of the problem is that the fine ingredients require 1-6 kWh/t of mixing energy, whilst the rough fractions require 0.3-0.5 kWh/t.
• the object of the present invention is to provide a composition, which is suited to the manufacture of concrete or mortar mass and which simultaneously utilises various mechanisms that add strength to the concrete, in a manner which enables the mixing to be kept simple.
• the present invention relates to a granular composition for the manufacture of concrete mass and the concrete or mortar mass that is manufactured from the same.
• composition according to the present invention is characterised by what is stated in the characterising part of Claim 1.
• the method for manufacturing the composition according to the invention is characterised by what is presented in Claim 9
• the concrete or mortar mass according to the invention is characterised by what is presented in Claim 14
• the method for manufacturing concrete or mortar mass is characterised by what is presented in Claim 16.
• Granules contain a lot of pores, which bind and absorb water by their capillary forces within a given time, whereby this water can be used for the hydration of the hydraulic binder components later on.
• the virtual ratio of water and cement during mixing and concrete casting is relatively high, whereby the mass is easy to cast, yet it stiffens fairly quickly in the mould.
• the Ca(OH) 2 that was formed in the hydration immediately forms extra precipitable CaCO 3 , if the kaolin is calcined by flue gases or otherwise in a carbon dioxide atmosphere.
• the Gibbs equation ( ⁇ ajgi — > minimum) also explains why the precipitable substances always precipitate on the surface of another particle. The minimisation takes place quicker, when the point of contact is not counted as a surface that is formed.
• the fines of the concrete can be moved to the mortar portion of the concrete, so that a homogeneous binder portion is formed.
• This is carried out by bringing, into the aggregate, pre-mixed fines in a correct proportion and as fairly large granules, and not in a ground form, as in the Ash Grove Cement Company patent, whereby the need of mixing water does not increase a great deal because of the large amount of fines, and the viscosity of the mass does not become high.
• the nature of concrete mixing changes into homogeneous mixing between these granules and the aggregate, whereby a power of mixing of 0.3 kWh/t is adequate.
• Fig. 1 shows equipment that is suitable for manufacturing a preferred grain composition according to the present invention.
• Fig. 2 is a drawing, which shows the external forms of the granules on a 240-fold enlargement, when manufactured in different ways; as a fluid in Fig 2a and as a non-fluid in Figs. 2b, 2c and 2d, whereby the fluid refers to metakaolin agglomerates that are coated in a gas flow, and the non-fluid refers to those mixed when dry.
• Fig. 3 shows electron microscope images of the metakaolin granules according to the invention
• Fig. 3a shows a 250-fold enlargement
• Fig. 3b shows a 4000-fold enlargement.
• the present invention thus relates to a grain composition for the manufacture of concrete mass, consisting of granules, each of which contains filler particles, to the surface of which hydraulic binder particles are attached.
• the invention also refers to a concrete or mortar mass, which, in addition to this grain composition, contains fine and coarse aggregates.
• concrete consists of a mortar portion, i.e., binder portion, and an aggregate portion, whereby the binder portion preferably comprises the following ingredients:
• - hydraulic binder such as Portland cement (OPC), which preferably contains C 3 A and C 4 AF portions
• - filler which preferably comprises limestone or SiO 2 stone
• - pozzolanic binder which preferably comprises metakaolin sinter (MKS), wherein the pozzolanically reactive portion comprises metakaolin, of which there is 10— 80% in the sinter;
• MKS metakaolin sinter
• water which preferably is normal industrial water or treated water [which contains, e.g., Ca(OH) 2 + 2CO 2 ⁇ Ca(HCO 3 ) 2 ], the aggregate preferably comprising the following ingredients:
• - fine aggregate (with an average particle size of ⁇ 6 mm, preferably ⁇ 4 mm, more preferably ⁇ 2 mm), which is preferably limestone, more preferably form-crushed limestone, or SiO 2 stone; more preferably in the form of crushed aggregate or natural stone; and
• - coarse aggregate (with an average particle size of 4-16 mm, the largest particles up to 32 mm), which preferably comprises crushed SiO 2 aggregate, natural SiO 2 stone, crushed limestone aggregate or so-called gangue from limestone mining.
• the aggregate comprises 50-85 % by weight of fine aggregate, more preferably 70-75 % by weight, and 15-50 % by weight of coarse aggregate, more preferably 25-30 % by weight.
• the fine stone aggregate that is used in the invention i.e., the "filling agent” or “filler” is preferably limestone, as both the concretion of carbonates and the so-called solid solution between CaCO 3 and Ca(OH) 2 can be implemented by it (Lea, The chemistry of cement and concrete, Third edition, 1970, page 266.). Tricalcium aluminate hydrate also forms quickly. This limestone can preferably be mixed with the "granule" in an amount of 2-30 % of the entire weight of the granule, most preferably about 15 %.
• this limestone component is brought into the filler granule at least partly on a so-called nano-scale, as in a suitable environment, particularly, the nano-scale particles tend to grow the quickest.
• the growing, re-crystallising particles attach to the surfaces of other particles by mechanical forces and so-called van der Waals vicinity forces.
• calcium carbonate nanoparticles also have the property that they facilitate the processibility of the concrete mass.
• the pozzolanic binder is preferably calcined clay that contains kaolinite or kaolin, part of which comprises metakaolin.
• the pozzolanic binder especially preferably comprises metakaolin sinter (MKS), which contains metakaolin, preferably 20-65 % by weight, kaolin, preferably 75-30 % by weight and calcium oxide (CaO), preferably 5-20 % by weight.
• MKS metakaolin sinter
• CaO calcium oxide
• it can preferably be coated with the particles of a hydraulic binder by most suitably using 30-120 % of hydraulic binder of the weight of the pozzolanic binder.
• the ratio of the hydraulic binder, which excretes calcium hydroxide in the hydration, and the pozzolanic binder is of a type, wherein the pozzolanic binder binds no more than 90 % of the calcium hydroxide that is released.
• the plasticizers can comprise polyacrylamide, polyacrylate, polycarboxylate, lignosulphonate, naphthalene sulphonate or melamine sulphonate or several of these, most preferably their polymers.
• a product which comprises only the binder granules, aggregate stone and water that are to be measured at the concrete mixing plant.
• the granules of the granular composition preferably contain
• fine aggregate preferably fine-ground calcium carbonate, most suitably the nanoparticles of calcium carbonate;
• the components of the concrete are grouped in a new manner by forming granules according to any of the following alternatives: Granule 1 :
• Core components are formed from the filler particles, and the calcium carbonate particles, to the surface of which the plasticizer is attached, are first added amongst these core components and, thereafter, the hydraulic binder.
• a granule is formed from the filler and the hydraulic binder, mainly comprising the core component that is formed from the filler particles, the plasticizer being attached to the surface of the core component and the particles of the hydraulic binder being attached around it. Calcium carbonate particles (with a size of ⁇ 800 nm) are then attached to this granule.
• Granule 3 (a special case of Granule 2): A granule is formed from limestone filler and the hydraulic binder, mainly comprising a core component made of the limestone filler, the plasticizer being attached to the surface of the core component and the binder particles being attached to this core component by means of the metaproduct Al(OH) 3 of the binder C 3 A and the hydration product of the limestone.
• the concrete is preferably mixed by adding the following ingredients in the said sequence:
• water or treated water containing Ca(HCOs) 2 the amount of which in the treated water is preferably about 10 g/1
• the binder system i.e. grain composition
• Metakaolin can be replaced or supplemented with silica and the cement with aluminous cement, etc.
• the idea of the invention is that all functional components are collected in one granule.
• the granules are easy to mix with the aggregate substance and water into a more homogeneous mixture and the mixture is easy to dose in the manufacture of concrete.
• the manufacturer of concrete only needs to by the "granule" for a certain purpose and only one silo is needed for the binder.
• the pozzolanic binder is suitably rendered the desired form by first agglomerating the kaolin, e.g., by spray drying, and not calcining until after this into metakaolin, preferably by hot flue gases.
• the metakaolin sinter (MKS) it brought into contact with a desired hydraulic binder, preferably so that a dispersing agent is present and, finally, said structured two-component agglomerate is coated, e.g., in a gas flow by fine calcium carbonate powder, preferably so- called nanoparticle calcium carbonate (n-PCC), which is manufactured by precipitating.
• the pozzolanic binder such as clay that contains kaolin
• an additive preferably an inorganic substance
• the slurry is dried in the gas flow and further calcined, at least on its surface, in a gas flow of 500-850 °C by methods known as such, but preferably in a gas flow that contains carbon dioxide.
• a suitable amount of concrete plasticizer is sprayed onto the surface of the calcined and cooled metakaolin agglomerate to bind the cement particles to the surface of the agglomerate, when cement dust and the agglomerates are brought into contact with each other. It should be noted that the cement dust and metakaolin adhere to each other by van der Waals forces even without the concrete plasticizer. In connection with the studies of the invention, it was observed that metakaolin collected other particles on its surface.
• the binder granule is manufactured directly, so that the metakaolin agglomerate that is manufactured according to the above and the hydraulic binder and the limestone filler are brought together in a dusty form (a fluid) and the particles are allowed to stabilize, e.g., in a fluidised bed over 10-60 sec and, after this, precipitated calcium carbonate slurry is sprayed amongst these ingredients together with the plasticizer.
• a dusty form a fluid
• precipitated calcium carbonate slurry is sprayed amongst these ingredients together with the plasticizer.
• an amount of water which corresponds to a maximum of 5-10 % of the chemical need of water of the hydraulic binder, is added into the mixture with the precipitated calcium carbonate.
• the other powders are mixed with each other in a dry form and, finally, the finished metakaolin agglomerates are mixed therewith, collecting the other particles on their surfaces.
• the patent US 6,027,561 of the Engelhard Corporation describes a method of forming metakaolin agglomerates, which essentially deviates from the present method, wherein the agglomerates are formed in an aqueous solution before calcination and which ensures that the agglomerate (in the calcination) obtains a strong structure. At the same time, energy is saved.
• the strength of the structure can be further improved by mixing a water-soluble inorganic compound with the mixing water, e.g., the mixing water of spray drying, which inorganic ingredient dries and binds more particles to each other.
• a water-soluble substance is preferably liquid glass which, after drying, dissolves in boiling water only.
• Gypsum can be used for the same purpose, or the soluble organic salts of calcium, such as formiate or acetate, in which cases the organic portion burns out in the calcination. This formation of agglomerate before calcination or partial calcination is dealt with, among others, in our previous patent application US 20050000393.
• the cement particles in the granules have average diameters of about 12 ⁇ m.
• the average diameter of the nanoparticles is 50-800 nm, preferably 100- 500 nm, most preferably 100-200 nm, and the average diameter of the microfiller is ⁇ 100 ⁇ m, preferably 10-40 ⁇ m.
• These components can be used to form a granule, the average diameter of which is ⁇ 300 ⁇ m, preferably 20-60 ⁇ m, most preferably 20-40 ⁇ m.
• the grain composition is manufactured so that the projection areas of the hydraulic binder and the calcium carbonate particles become as large as or smaller than the areas of the filler particles of the granules.
• the outermost layer of the granule surface preferably mainly consists of cement particles, wherein the C 3 A has slightly reacted after drying.
• gas remains in the granule, which gas is air, helium or carbon dioxide, depending on the way of formation.
• the amount of gas is 0.8—1.2 dm 3 / kg of granule.
• the attachment of the cement particles to the surfaces of the filler particles takes place by utilising the quick hydration of the C 3 A of the binder granule.
• This hydration time remains constant for 6 min - Ih, even 2 min - Ih.
• the filler particles, the surface of which is watered, together with the metastable product Al(OH) 2 of the C 3 A of the binder particles form a hydrate, which binds the binder particle to the surface of the filler particle.
• a granule is obtained, which can preferably be blended as binder with the concrete.
• the hydration of the filler/binder granule continues in the concrete, when water is included.
• the quick hydration of the granule thus produced is surprising; being quicker than if the different components of the binder composition are added separately into the concrete.
• the CaCO 3 nanoparticles contained in the granules improve the processibility and, through that, reduce the need of water in the processing, further reducing the formation of so-called capillary pores, thus adding to the frost, fire and corrosion resistances of the concrete.
• the plasticity can be adjusted by the invention by adding into the concrete, at the end stage of mixing (however, before casting the concrete), metakaolin sinter powder, which absorbs the water that moves in the mixing, thus working as a water supply in the progress of the hydration.
• Adding the filler and the hydraulic binder in one granule to the concrete mixing influences the amount of mortar portion required and, in this way, a greater amount of filler can be used without growing the water to binder (w/c) ratio.
• the purpose of using the filler is to influence this w/c ratio, the target value of which is 0.4:
• w is the amount of water
• c is the amount of cement
• c re( i is the amount of cement, wherein the effect of the amount of filler is taken into consideration
• F is the amount of filler
• k is the coefficient, which indicates the effect of the filler amount on the amounts of cement and water (wherein the amounts are given as weights).
• the target value of the coefficient k is 0.25.
• the target value is fulfilled, e.g., in a case, in which:
• This ratio in particular the c value that corresponds to the cement, can be influenced, among others, by adjusting the amount of binder, the mutual ratios of the hydrate and the filler, and their amounts, ability to mix and processibility. By adjusting the other amounts and ratios, savings can also be made in the amount of cement, i.e., the binder.
• the space between the particles of the hydraulic binder has a diameter of about 700 nm.
• the nanoparticles of calcium carbonate must fit in this space, where they partly hydrate and reduce the volume, which in the concrete of prior art is filled with water. Therefore, the nanoparticles preferably have average diameters of ⁇ 200 nm. When treated with plasticizer, these nanoparticles plasticize the binder composition.
• Drying shrinkage is a common problem with concrete, impeding the quality of the final concrete. It is caused by the gel water and the capillary water that remain between the particles in the concrete. A general value of drying shrinkage is 0.6 %o. To eliminate the disadvantages caused by the drying shrinkage on the quality of the concrete, the drying shrinkage should however be lower than the breaking stretch of concrete, which generally is about 0.2-0.3 %o. In the present invention, the drying shrinkage is reduced by introducing, between the coarse particles of the concrete, finer particles, such as microfiller along with the granules.
• the granules which remain between the aggregate particles of the concrete and contain the limestone filler and the hydraulic binder, increase the volume filled with the binder composition between the aggregate particles. When the binder hardens, this reduces the deformations of the hydrate thus formed, which cause the drying shrinkage mentioned above, among others.
• the size of the space between the aggregate influences the amount of microfiller needed and its particle size, and the size of the space is further influenced by the particle size of the aggregate. Due to this, preferable filler is the one, which has particles with an average diameter of 10-40 ⁇ m.
• the amounts of ingredients added can be as follows:
• 20 ⁇ 4-0 % by weight of the hydraulic binder is separately added amongst the MKS, whereby it adheres to the surfaces of the sinter particles.
• composition is manufactured using amounts of substances, the mutual ratio of which essentially corresponds to any of the following composition examples: Composition 1 Composition 2
• fine aggregate is preferably added into the paste thus obtained in an amount of about 1000 kg in the case of the composition examples.
• the concrete mass is mixed of the mortar by adding coarse aggregate in an amount of about 1000 kg in the case of the composition examples.
• Water may also be carried to the composition as various hydration products or absorbed into the granules of the composition.
• Water is preferably added in suitable amounts as hydration water and for the hydraulic binder, the pozzolanic reaction and the absorption water of the MKS. It is assessed that, of the water used in the composition example 1, 100 kg is most suitably needed for the hydraulic binder, 10 kg for the pozzolanic reaction and 60 kg for the absorption water of the MKS.
• the present invention also relates to equipment, by means of which the granules of the grain composition according to the invention can be manufactured.
• the said equipment preferably contains the following components (Fig. 1):
• the equipment thus contains a first container 1, a cyclone separator 2, which is placed downstream of the first container 1, a pressure roller 3, which is attached to the bottom part of the cyclone separator 2, an opposed cylinder rotor distributor 4, which is correspondingly attached to the pressure roller 3, coating equipment 6, which is in contact with the upper part of the cyclone separator 2 and to which a second container 5 is attached, mixing equipment 7, which is placed downstream of the coating equipment 6, and a storage tank 8, which is placed downstream of the mixing equipment 7.
• This granule formation equipment preferably functions so that the ingredient which is needed by the granule, such as the hydraulic binder, can be fed from the first container 1 into the cyclone separator 2.
• fine particles are separated from coarse ones.
• the coarse particles with sizes of preferably > 15 ⁇ m are ground fine by feeding them through the bottom part of the separator 2, first through the pressure roller 3 and then the opposed cylinder rotor distributor 4, after which they are combined with the hydraulic binder that is conveyed from the first container 1, whereby the partly pulverised binder particle mixture thus formed is conveyed back to the cyclone separator 2.
• Pressure roller crushing can be used to reduce the relative size of the largest particles, whereby their size distribution becomes even.
• the fine particles which are separated from the coarse ones in the cyclone separator 2 and which preferably have sizes of ⁇ 15 ⁇ m, are conveyed through the upper part of the separator 2 into connection which the coating equipment 6, where they are mixed with the feed that comes from the coating equipment 6 and preferably contains a microfiller, which is conveyed from the second container 5 and coated with calcium carbonate in the coating equipment 6, a plasticizer being attached to the calcium carbonate, and preferably with a feed that contains a pozzolanic binder.
• the substances thus coated are fed from the coating equipment 6 into the mixing equipment 7, where the microfiller calcium carbonate particles are mixed with the binder particles, after which the granules thus formed, are conveyed to the storage tank 8 to be stored before use.
• the equipment also contains calcination equipment, including a calcination furnace, which is in contact with the coating equipment 6 and the mixing equipment 7, and the pozzolanic binder can be rendered its desired form in the calcination equipment, i.e., it can preferably be agglomerated and calcined before combining with the other components of the granule.
• the concrete mass according to the invention contains, mixed together, the granular composition described above and stone aggregate and water.
• the mass is manufactured by granulation from this grain composition, which contains at least the binder, an additive and fine aggregate in predefined proportions, after which said granules are mixed with stone aggregate and water.
• Kaolin was elutriated by first mixing it into an aqueous slurry of 55 %, then it was treated by a dispergator and was adjusted with a NaOH solution to a pH value of 7.5. A slurry was obtained, the viscosity of which at a temperature of 21°C was 520 cP. A saturated Ca(HC03)2 -a solution was added into the slurry, so that, when counted as CaC ⁇ 3 , the amount of dissolved carbonate was 1.8% of the amount of dry matter. This slurry was spray-dried and particles with a diameter of 11.4 ⁇ m were obtained, of which the d 90 was 9.9 ⁇ m. It was observed that the agglomerate particles thus formed were spherical and almost equal in size.
• the calcination in this test took place in an electric resistance furnace manufactured by the Bentrup Company and in a calcined clay melting pot in 1.5 kg batches, so that the temperature was slowly raised from room temperature up to 1050°C, where it was kept for an hour.
• the mass defect totalled 12.61%, whereby it could be calculated that the kaolin content apparently was 88%.
• the granules according to the invention (Fig. 3) were manufactured by mixing the ingredients according to the following composition (Fig. 2, non-fluid) under dry conditions:
• the nano PCC together with a small amount of water and with the water that came along with the plasticizer were first added into this composition.
• the total amount of water used was 7 % of the entire amount of dry matter and 10 % of the amount of cement.
• the composition of each granule thus formed corresponded to this average composition.

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• Chemical & Material Sciences (AREA)
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• Civil Engineering (AREA)
• Dispersion Chemistry (AREA)
• Nanotechnology (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Curing Cements, Concrete, And Artificial Stone (AREA)

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Cited By (7)

Citations (10)

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• 2008
  • 2008-10-01 FI FI20085927A patent/FI123552B/sv not_active IP Right Cessation
• 2009
  • 2009-09-28 WO PCT/FI2009/050770 patent/WO2010037903A1/en active Application Filing
  • 2009-09-28 RU RU2011114905/03A patent/RU2526920C2/ru active
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