JP2006298737A - Special mineral water for manufacturing heat resistant, fire resistant and reinforced concrete and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide special mineral water for inexpensively manufacturing concrete excellent in heat resistance, fire resistance and strength and its manufacturing method. <P>SOLUTION: The special mineral water contains a Ca ion of 200-1,000 ppm, an Fe ion of 3-30 ppm, an Mg ion of 10-150 ppm, an Na ion of 10-90 ppm and carbon dioxide of 0.001-0.05 mol/kg. The mineral water is manufactured by the method that ferric oxide is charged in an acid water in which heaped aragonite is dissolved in advance and that the dissolving amount of carbon dioxide is adjusted by charging dry ice after sufficient agitation. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a special mineral water for producing heat-resistant / fire-resistant / reinforced concrete capable of preventing explosion even when heated at a high temperature, and a method for producing the same.

  Alumina cement, phosphate cement, magnesia cement and the like are known as conventional cements for producing concrete having fire resistance.

  Alumina cement is a cement mainly made of bauxite and limestone, which are aluminum raw materials. For example, as described in Patent Document 1, this alumina cement is a cement produced by adding ultrafine powdery alumina, and is most often used as a current refractory concrete such as an incinerator. .

  As disclosed in Patent Document 2, the phosphate cement is a hydraulic cement to which a metal salt of phosphoric acid or a metal salt of boric acid is added. This phosphate cement is used, for example, as a phosphate cement foam mainly used for fireproof boards.

On the other hand, magnesia cement is an air-hardening cement obtained by adding chloride to fired magnesium oxide and hardening it. The magnesia cement described in Patent Document 3 is used by being added to a fireproof coating material, and is used as a heat absorbing material / binding material.
Japanese Patent Publication No. 47-40694 Japanese Patent Laid-Open No. 4-83771 JP-A-7-157378

  The refractory cements described in each patent document have the following problems. For example, alumina cement is a material to which an ultrafine powdery alumina material is added, so the cement itself must be very expensive. Currently, a technique using a-alumina powder has been developed in order to improve the fire resistance and strengthening performance. However, in order to improve such a performance, the cement becomes more expensive.

  On the other hand, with phosphate cement and magnesia cement, it is possible to improve fire resistance, but there is still a problem in strength. Therefore, when these refractory cements are used as concrete, they are often used together with any other reinforcing material, or as refractory coatings that cover the surface of steel. there were. As described above, phosphate cement and magnesia cement can be used as heat and refractory concrete, but cannot be used as reinforced concrete.

  Furthermore, since concrete and reinforced concrete using Portland cement generally used contain a lot of moisture, there is a risk of explosion when the temperature becomes high. In particular, reinforced concrete contains a lot of moisture, and it is known that an extremely dangerous explosion occurs when heated to 400 to 500 degrees Celsius. Moreover, in concrete using Portland cement, there is a risk of cracking at about 800 degrees Celsius and explosion at a temperature higher than this. Moreover, there is a risk that the concrete will collapse if it is poured with water. Therefore, the current situation is that fires in concrete structures are hindering fire fighting activities.

  The inventor newly improved that explosion resistance is improved by using alkaline water containing a specific alkaline component in kneaded water used in production in concrete production using commonly used Portland cement. I found it. The present invention was created to solve the above-mentioned problems, and aims to provide a special mineral water used for producing heat-resistant, fire-resistant and reinforced concrete that can be produced at low cost using ordinary Portland cement and a method for producing the same. It is a thing.

  The first means of the present invention contains 200 to 1000 ppm of Ca ions, 3 to 30 ppm of Fe ions, 10 to 150 ppm of Mg ions, and 10 to 90 ppm of Na ions in water used for heat-resistant / fireproof / reinforced concrete production. In addition, carbon dioxide is contained in an amount of 0.001 to 0.05 mol / kg.

  The second means is a method for producing special mineral water in which deposited aragonite is dissolved with citric acid water, ferric oxide is added, and after sufficiently stirring, dry ice is added to adjust the amount of dissolved carbon dioxide. It is in.

  According to the present invention, it has succeeded in providing reinforced concrete having extremely excellent heat resistance and fire resistance by using mineral water containing an alkaline component and dilute carbon dioxide in kneaded water. Such special reinforced concrete has been realized by many experiments, but according to the inventors, it is presumed that the pozzolanic reaction rapidly progressed due to Brownian motion in which molecules collide with ultrafine particles. The

  Since the reinforced concrete of the present invention is obtained by kneading ordinary Portland cement and sand with special mineral water and naturally drying, it can be produced by a production method mainly using ordinary stirring in a general concrete factory. In addition, since a special and expensive material such as conventional concrete using alumina cement is not required, it can be manufactured at a low cost.

  Furthermore, according to the reinforced concrete of the present invention excellent in heat resistance and fire resistance, it can be used as heat resistant concrete for high temperature furnaces such as incinerators, blast furnaces, ceramic kilns and the like. Moreover, it can be used as fireproof and external insulation concrete for fire walls and structures of tunnels, subways, science factories, fireworks manufacturing factories, tire manufacturing factories, thermal power plants, nuclear power plants and the like.

  As described above, when the special alkaline water of the present invention is used for concrete production, the concrete has excellent effects such as excellent heat resistance, fire resistance and strength of the concrete and low production cost.

  The best mode of the present invention contains Ca ions of 200 to 1000 ppm, Fe ions of 3 to 30 ppm, Mg ions of 10 to 150 ppm, Na ions of 10 to 90 ppm, and carbon dioxide of 0.001 to 0.05 mol / Special mineral water containing kg is used as mixed water at the time of concrete production. As a method for producing this mineral water, use a method in which deposited aragonite is dissolved in citric acid water, and then ferric oxide is added, and after sufficiently stirring, dry ice is added to adjust the amount of dissolved carbon dioxide. Thus, the production of inexpensive and stable special mineral water is achieved.

  The special mineral water of the present invention is used as a concrete mixed water excellent in heat resistance, fire resistance, and strength with ordinary cement and sand, and in particular, after depositing aragonite with citric acid water, ferric oxide And the mixture is sufficiently stirred, and then dry ice is added to adjust the amount of carbon dioxide dissolved.

  An example of a specific method for producing mineral water for kneading the concrete material of the present invention is shown below. 30 g to 60 g of citric acid is mixed with 20 liters of water to adjust the pH to 2-3, and then the deposited aragonite is immersed in this water for a long time to adjust the pH to 6.5 to 7. In the experiment, mineral water having a pH of 6.5 to 7 is obtained in about one month. Aragonite 500g-800g was immersed. Further, ferric oxide is mixed and stirred sufficiently, and then dry ice is added to adjust the amount of carbon dioxide.

  By appropriately adjusting the amount of deposited aragonite, ferric oxide and dry ice, it contains 200 to 1000 ppm of Ca ions, 3 to 30 ppm of Fe ions, 10 to 150 ppm of Mg ions, and 10 to 90 ppm of Na ions. And the special mineral water which contained 0.001-0.05 mol / kg of carbon dioxide is obtained.

Portland cement, which is generally used for cement, is mixed with sand and the special alkaline water of the present invention, then poured into a formwork or on-site, and cured by natural drying, strengthening with extremely excellent heat resistance and fire resistance It becomes concrete.
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  In the experiment, a block of about 100 × 80 × 7 mm was formed from the concrete of the present invention, and this surface was heated with an acetylene gas burner of about 3000 degrees Celsius for about 5 minutes. As a result, a dent of about 2 mm was formed on the heating surface, and an amber-colored glass was confirmed on the surface, but no explosion occurred. Moreover, no change was observed on the opposite surface of the heating surface.

  In another experiment, the concrete of the present invention having a thickness of 50 mm was heated with a gas burner at 1800 degrees Celsius for 2 to 3 hours, and no explosion occurred. The temperature on the opposite side of the heated surface was about 250 degrees Celsius. It changed. It is confirmed that the concrete of the present invention having a thickness of 50 mm has a strength of at least 37 Newton (370 kg) or more.

  In yet another experiment, immediately after heating the concrete of the present invention with a gas burner at 1000 degrees Celsius, no cracks occurred and no explosion occurred even if it was returned to tap water. Therefore, even if the concrete structure of the present invention is in a fire, a safe fire extinguishing activity is possible.

Claims (2)

  200 to 1000 ppm of Ca ions, 3 to 30 ppm of Fe ions, 10 to 150 ppm of Mg ions, 10 to 90 ppm of Na ions, and 0.001 to 0.05 mol / kg of carbon dioxide Special mineral water for heat, fire and reinforced concrete production.   2. The dissolved aragonite is dissolved with citric acid, and then ferric oxide is added, and after sufficiently stirring, dry ice is added to adjust the amount of dissolved carbon dioxide. A method for producing special mineral water.