JP4835926B2 - Method for suppressing ammonia generation from mortar / concrete and mortar / concrete member - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for suppressing evolution of ammonia from mortar/concrete which can simply and surely suppress evolution of ammonia without restricting materials to be used, and a mortar/concrete member treated by using this method. <P>SOLUTION: This method for suppressing evolution of ammonia from mortar/concrete comprises removing ammonia in mortar/concrete 2 by forcibly blowing a gaseous fluid against the surface of the mortar/concrete 2. Alternatively this method comprises removing ammonia in mortar/concrete 2 by accommodating the mortar/concrete 2 in a chamber 3 and depressurizing inside the chamber 3. Further this method comprises encapsulating carbon dioxide in a chamber 3 accommodating the mortar/concrete 2, so that ammonia is made to react with carbon dioxide infiltrated into the inside from the surface of the mortar/concrete 2 to be converted to a carbonate. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  The present invention relates to a method for suppressing ammonia generation from mortar / concrete used in facilities where it is necessary to suppress the generation of ammonia, such as a semiconductor device manufacturing factory or a museum, and a mortar / concrete member treated by this method.

  Conventionally, semiconductor device process processing steps are performed in a clean room maintained in an air environment of a specified cleanliness. Concrete (or mortar) such as factory walls, floors, and pillars for performing this process step is used. ) Is discharged from ammonia (ammonia gas), and the semiconductor device is contaminated by this ammonia. Also, in museums and art collection facilities, the metal (silver, copper, etc.) and fibers of art works may be discolored by the ammonia generated from the concrete that constitutes the facilities, and oil painting deterioration and varnishing may occur. There was a problem that white turbidity occurred.

  It is speculated that such ammonia is generated by hydrolysis of organic matter (amine-based grinding aid) in the cement and organic matter (amide nitrogen and amino sugar nitrogen) on the surface of the aggregate by cement alkali. Yes. For this reason, in facilities (concrete structures) such as semiconductor device manufacturing factories and museums, an expensive chemical filter is installed to remove ammonia from the air in the facility, or the constructed concrete structure is left for a long period of time. As a result, measures such as waiting for the release of ammonia from the mortar / concrete (mortar / concrete member) to start use are forced, leading to an increase in initial cost and running cost.

On the other hand, in order to suppress the generation of ammonia from mortar and concrete, the aggregate to be used is pre-heated, or the amount of released ammonia is reduced by using early strong cement (for example, Patent Document 1, Measures such as affixing a sheet with excellent ammonia adsorption performance to the surface of mortar / concrete after construction (see, for example, Non-Patent Document 1) have been proposed and implemented.
JP-A-10-287462 JP 2004-284902 A Mitsuka Ichifusa, Iwanami Hiroshi: A method for preventing alteration and deterioration of cultural properties caused by ammonia-Development background and overview of "Da Vinci Method", Monthly Building Finishing Technology, May 1997 issue, p. 57-61 (1997)

  However, when suppressing the generation of ammonia using heat-treated aggregates or early-strength cement, there are significant restrictions on the selectivity of the materials used, and ammonia for concrete structures constructed with general-purpose materials It is not possible to suppress the occurrence of On the other hand, even when a sheet with excellent ammonia adsorption performance is pasted, the environment where it can be used is limited and the versatility is difficult, and at the time of pasting the sheet, to secure the adhesion between the sheet and mortar / concrete However, there is a problem in that the mortar / concrete surface needs to be subjected to kelen treatment, and measures for dust treatment caused by this treatment are required separately.

  In view of the above circumstances, the present invention is a method for suppressing ammonia generation from mortar / concrete capable of easily and reliably suppressing the generation of ammonia without limiting the materials used, and a mortar treated using this method. It aims at providing a concrete member.

  In order to achieve the above object, the present invention provides the following means.

The method for suppressing the generation of ammonia from mortar / concrete according to the present invention is a method for suppressing the generation of ammonia from mortar / concrete, and comprises a surface on which the gas adsorbent, activated carbon, and ULPA filter are provided. The clean air that has passed through the air generating device is forcibly sprayed in a predetermined amount corresponding to the surface area to remove the ammonia in the mortar and concrete. In the present invention, mortar / concrete means mortar or concrete.

Further, the ammonia generation suppression method from mortar and concrete of the present invention, the gas adsorbent, accommodates the mortar and concrete into the chamber with clean air generating device having activated charcoal and ULPA filters, the clean air generating device Clean air that has passed through is forcedly sprayed onto the surface of the mortar concrete to remove the ammonia in the mortar concrete.

Furthermore, the method for suppressing ammonia generation from mortar and concrete according to the present invention includes removing the ammonia in the mortar and concrete by containing the mortar and concrete in the chamber and reducing the pressure in the chamber. Features.

Further, in the method for suppressing ammonia generation from the mortar / concrete of the present invention, the mortar / concrete is accommodated in a chamber and carbon dioxide is enclosed in the chamber, and the carbon dioxide is removed from the surface of the mortar / concrete. Reacting with ammonia in the mortar concrete while invading inside, the ammonia to carbonate , reducing the pressure in the chamber, to promote the movement of the ammonia in the mortar concrete to the surface, Further, forcibly spraying clean air that has passed through a clean air generating device equipped with a gas adsorbent, activated carbon and a ULPA filter on the surface of the mortar concrete to remove the ammonia in the mortar concrete. Features.

  The mortar / concrete member of the present invention is a mortar / concrete member used for construction of a concrete structure, and is characterized by being treated by any of the methods described above to suppress generation of ammonia.

According to the method for suppressing the generation of ammonia from mortar and concrete according to the present invention, the clean air that has passed through the clean air generating device including the gas adsorbent, the activated carbon, and the ULPA filter is forcibly sprayed on the surface of the mortar and concrete. Therefore, ammonia on the surface of the mortar concrete can be removed, and an ammonia concentration gradient can be formed between the inside and the surface of the mortar concrete. Thereby, the movement of ammonia from the inside where the ammonia concentration is high to the surface where the ammonia concentration is low can be promoted, and the evaporation of the ammonia which has moved to the surface can be promoted. Therefore, by applying such a simple treatment, ammonia in the mortar and concrete can be removed, and the mortar and concrete can be removed from the mortar and concrete without limiting the materials constituting the mortar and concrete as in the past. Generation of ammonia can be suppressed.

  Further, according to the method for suppressing ammonia generation from mortar / concrete of the present invention, a pressure gradient from the inside of mortar / concrete to the surface can be formed by accommodating the mortar / concrete in the chamber and reducing the pressure. . Thereby, ammonia in mortar and concrete can be moved to the surface at an early stage, and transpiration from the surface to the outside can be promoted. Therefore, by applying such a simple treatment, ammonia in the mortar and concrete can be removed, and the mortar and concrete can be removed from the mortar and concrete without limiting the materials constituting the mortar and concrete as in the past. Generation of ammonia can be suppressed.

  Furthermore, according to the method for suppressing ammonia generation from mortar / concrete according to the present invention, carbon dioxide can be caused to enter the interior of the mortar / concrete by enclosing carbon dioxide in a chamber containing mortar / concrete. it can. The invading carbon dioxide reacts with the internal ammonia to form a carbonate, whereby the ammonia can be retained in the mortar concrete. Thereby, it can prevent that ammonia discharge | releases from the surface of mortar concrete. In addition, when the carbonate of ammonia is formed in this way, the gap between the mortar and concrete can be clogged and blocked with this carbonate. Can be prevented from being released from the surface. Therefore, by applying such a simple treatment, it is possible to suppress the movement of ammonia in the mortar and concrete, and without restricting the materials constituting the mortar and concrete as in the past, Generation of ammonia from concrete can be suppressed.

  Moreover, by reducing the pressure in the chamber, ammonia in the mortar / concrete can be moved to the surface side at an early stage, and the reaction with carbon dioxide that has entered the interior from the surface of the mortar / concrete can be promoted.

  Furthermore, according to the mortar / concrete member treated as described above, the generation of ammonia is suppressed, so an expensive chemical filter is installed in a facility (concrete structure) constructed using the mortar / concrete member. There is no need to install it, and the economy can be improved. Moreover, since it is not necessary to leave a concrete structure for a long time after constructing a concrete structure, the facility can be used early.

  Hereinafter, with reference to FIG.1 and FIG.2, the mortar concrete member processed by this method and the ammonia generation | occurence | production suppression method (henceforth an ammonia generation | occurrence | production suppression method) from the mortar concrete which concerns on 1st Embodiment of this invention is demonstrated. To do. Here, the present embodiment is a method for suppressing generation of ammonia released from mortar / concrete by forcibly spraying clean air (gaseous fluid) onto mortar / concrete (mortar / concrete member) after molding. It is about.

  As shown in FIG. 1, the ammonia generation suppression device 1 used in the ammonia generation suppression method of the present embodiment cleans the chamber 3 containing mortar concrete (mortar concrete member) A and the air supplied into the chamber 3. The apparatus includes a clean air generating device 4 for generating a gas, two impingers 5 containing a collection liquid 5a, a flow meter 6, a mass flow meter 7, and a pump 8. Here, the clean air generation device 4 includes a gas adsorbent 9, activated carbon 10, and a ULPA filter (Ultra Particulate Air Filter) 11. And the clean air production | generation apparatus 4, the chamber 3, the two impinger 5, the flow meter 6, the mass flow meter 7, and the pump 8 are connected in series through the pipe in this order, and by driving the pump 8, Air purified through the gas adsorbent 9, activated carbon 10, and ULPA filter 11 is supplied to the chamber 3.

The mortar / concrete 2 is accommodated in the chamber 3 of the ammonia generation suppressing device 1 configured as described above, and the clean air sent from the clean air generating device 4 to the surface of the mortar / concrete 2 is, for example, the surface of the mortar / concrete. forcibly blown by the wind of 1 m ² per 0.5 liters / S～5 l / s. Then, the air exhausted from the chamber 3 along with the supply of clean air to the chamber 3 is sent to the two impingers 5 via the piping, and the collected liquid 5a in the impinger 5 is aerated. At this time, if ammonia exists in the air exhausted from the chamber 3, the ammonia is collected in the collection liquid 5 a of the impinger 5.

  When clean air is sprayed on the surface of the mortar / concrete 2 as described above, ammonia present on the surface is evaporated and removed. When the ammonia on the surface of the mortar / concrete 2 is removed, an ammonia concentration gradient is formed between the inside and the surface of the mortar / concrete 2. Thereby, the movement of ammonia from the inside of the mortar / concrete 2 toward the surface is promoted, and the ammonia that has moved to the surface is sequentially evaporated and removed by clean air. Therefore, ammonia in the mortar concrete 2 is removed by continuously spraying clean air on the surface of the mortar concrete 2 in this way.

  Here, FIG. 2 shows a case in which clean air is blown onto the mortar / concrete 2 using the above-described ammonia generation suppressing device 1 (forced air drying) and a case where the mortar / concrete 2 is stored in a sealed state without blowing clean air. The relationship between the ammonia generation rate of each mortar and concrete 2 and the elapsed days is shown. In this figure, the vertical axis represents the ammonia generation rate, the horizontal axis represents the number of days elapsed, and the vertical axis represents the ratio of the ammonia generation rate of the mortar / concrete 2 at 100 days as 100%. . The ammonia generation rate of the mortar / concrete 2 is determined by measuring the ammonia concentration of the collected liquid 5a collected from the impinger 5 every predetermined period with an ion chromatography analyzer and calculating the ammonia concentration and the elapsed time (elapsed days). Calculated.

  From FIG. 2, when the mortar / concrete 2 is stored sealed, it takes about 35 days for the ammonia generation rate (ratio) to decrease to around 40%, whereas when clean air is blown, It can be confirmed that the ammonia generation rate decreases rapidly immediately after the start of blowing clean air and decreases to around 40% in about 10 days.

  Therefore, according to the ammonia generation suppression method for forcibly spraying clean air (gaseous fluid) on the mortar / concrete 2 according to the present invention, the ammonia in the mortar / concrete 2 can be transferred to the surface by a simple method. It can be removed while promoting transpiration, and generation of ammonia from the mortar / concrete 2 can be suppressed at an early stage. Therefore, by applying the mortar / concrete (mortar / concrete member) 2 thus treated to a concrete structure such as a semiconductor process factory or a museum, for example, it is not necessary to install an expensive chemical filter in the semiconductor process factory. Therefore, it is possible to improve the economic efficiency, and it is not necessary to leave the structure for a long time after the construction of a concrete structure such as a semiconductor process factory or a museum, so that the facility can be used at an early stage.

As mentioned above, although embodiment of the ammonia generation | occurence | production suppression method from the mortar concrete which concerns on this invention and the mortar concrete member processed by this method was described, this invention is not limited to said 1st Embodiment, Changes can be made as appropriate without departing from the spirit of the invention .

  In the present embodiment, the ammonia generation suppression device 1 is used to blow a gaseous fluid (clean air) onto the mortar / concrete (mortar / concrete member) 2 accommodated in the chamber 3. The generation of ammonia may be suppressed by forcibly blowing the atmosphere (gaseous fluid) with a blower or the like to the mortar / concrete 2 that is not accommodated therein. In this case, the same effect can be obtained by blowing air at a wind speed of about 3 to 6 m / s.

  Next, with reference to FIG. 3, a method for suppressing ammonia generation from mortar / concrete according to a second embodiment of the present invention and a mortar / concrete member treated by this method will be described. Here, the present embodiment relates to a method for suppressing the generation of ammonia from mortar / concrete by storing the molded mortar / concrete (mortar / concrete member) in a chamber and holding it under reduced pressure. is there.

  As shown in FIG. 3, the ammonia generation suppression device 20 used in the ammonia generation suppression method of this embodiment is substantially the same as the ammonia generation suppression device 1 of the first embodiment, and is provided in the chamber 3 that houses the mortar / concrete 2. A vacuum pump 21 is attached.

In a stage where the mortar / concrete 2 is accommodated in the chamber 3 of the ammonia generation suppressing device 20 configured as described above, the pressure in the chamber 3 is reduced to, for example, 10 ⁻² to 10 ⁻⁵ Pa. Thereby, in the mortar concrete 2 in the chamber 3, a pressure gradient from the inside to the surface is formed, and the ammonia inside moves to the surface at an early stage. And the ammonia which moved to this surface will evaporate outside sequentially. By exposing the mortar concrete 2 under such reduced pressure for 6 to 24 hours, the ammonia generation rate is reduced to about 40%.

  Therefore, according to the method for suppressing ammonia generation by exposing the mortar concrete according to the present invention under reduced pressure, it is possible to remove ammonia in the mortar concrete 2 while facilitating movement and transpiration to the surface. It becomes possible to suppress the generation | occurrence | production of ammonia from the mortar concrete 2 at an early stage. Therefore, by applying the mortar / concrete (mortar / concrete member) 2 thus treated to a concrete structure such as a semiconductor process factory or a museum, for example, it is not necessary to install an expensive chemical filter in the semiconductor process factory. Therefore, it is possible to improve the economic efficiency, and it is not necessary to leave concrete structures such as semiconductor process factories and art museums for a long time after construction, so that facilities can be used at an early stage.

  In addition, this invention is not limited to said 2nd Embodiment, In the range which does not deviate from the meaning, it can change suitably. For example, in the present invention, the mortar / concrete 2 may be held in an exposed state under reduced pressure, and the ammonia generation suppressing device 20 shown in the present embodiment is not necessarily used.

  Next, with reference to FIG. 4 and FIG. 5, a method for suppressing ammonia generation from mortar / concrete according to a third embodiment of the present invention and a mortar / concrete member treated by this method will be described. Here, in the present embodiment, the molded mortar-concrete (mortar-concrete member) is accommodated in a chamber, held in a reduced pressure state, and carbon dioxide is enclosed in the chamber, so that ammonia from the mortar-concrete is contained. The present invention relates to a method for suppressing the occurrence.

  As shown in FIG. 4, the ammonia generation suppression device 30 used in the ammonia generation suppression method of the present embodiment is substantially the same as the ammonia generation suppression device 20 of the second embodiment, and the inside of the chamber 3 that houses the mortar / concrete 2. Carbon dioxide supply means 31 is provided for supplying carbon dioxide.

  At the stage where the mortar / concrete 2 is accommodated in the chamber 3 of the ammonia generation suppressing device 30 configured as described above, the pressure in the chamber 3 is reduced. Thereby, in the mortar concrete 2 in the chamber 3, a pressure gradient from the inside to the surface is formed, and the ammonia inside moves to the surface at an early stage. In the present embodiment, carbon dioxide is supplied from the carbon dioxide supply means 31 into the chamber 3 and sealed so as to be, for example, 0.3 MPa, and the mortar / concrete 2 is cured for 24 hours to 100 hours in this state. . In this way, carbon dioxide enters the mortar concrete 2 exposed to carbon dioxide from its surface. And the ammonia which moved to the surface reacts with the carbon dioxide which penetrate | invades sequentially, and carbonate is formed in the surface and surface layer. Thereby, the carbonated ammonia has its vapor pressure reduced and is retained in the mortar concrete 2. Moreover, since the gap | interval of the mortar concrete 2 is clogged with carbonate, the movement to the surface of the ammonia which is not carbonated inside is prevented, and generation | occurrence | production of ammonia from the mortar concrete 2 is suppressed.

FIG. 5 shows splitting of mortar concrete 2 (FIG. 5 (a)) not exposed to carbon dioxide and mortar concrete 2 (FIG. 5 (b)) exposed to carbon dioxide, and phenol on the splitting surface. The state which sprayed the phthalein solution is shown. Reference numeral 32 denotes a colored portion where the alkali component of the mortar / concrete 2 has reacted with the phenolphthalein solution. Moreover, the code | symbol 33 has shown the coarse aggregate.
From this figure, the surface of the mortar concrete 2 that has not been exposed to carbon dioxide is colored with a phenolphthalein solution, whereas the surface and surface of the mortar concrete 2 that has been exposed to carbon dioxide have a phenolphthalein solution. It can be confirmed that carbon dioxide permeates into the surface and the surface layer portion and the alkali component caused by calcium hydroxide, ammonia and the like is carbonated.

  Therefore, according to the method for suppressing the generation of ammonia from mortar / concrete according to the present embodiment, the carbon dioxide that has entered the interior from the surface of the mortar / concrete 2 reacts with the ammonia inside to form carbonate. Can be held in mortar and concrete. Thereby, by giving such a simple process, the movement of ammonia in the mortar / concrete 2 can be suppressed, and without limiting the material constituting the mortar / concrete 2 as in the past. The generation of ammonia from the mortar / concrete 2 can be suppressed.

  Moreover, by depressurizing the inside of the chamber 3 containing the mortar / concrete 2, ammonia in the mortar / concrete 2 can be moved to the surface side, and the reaction with the invading carbon dioxide can be promoted. Thereby, the space | gap on the surface side of the mortar concrete 2 can be clogged with many carbonates, and it can prevent reliably that ammonia in the mortar concrete 2 which is not carbonated is discharge | released from the surface.

  Furthermore, according to the mortar / concrete member 2 treated as described above, the generation of ammonia is surely suppressed, so that it is not necessary to install an expensive chemical filter in the facility, and the economic efficiency can be improved. In addition, since it is not necessary to leave concrete structures such as semiconductor process factories and museums for a long time after construction, facilities can be used at an early stage.

  In addition, this invention is not limited to said 3rd Embodiment, In the range which does not deviate from the meaning, it can change suitably. For example, in this embodiment, the mortar / concrete 2 is stored in the chamber 3 and decompressed, and then exposed to carbon dioxide. However, it may be exposed to carbon dioxide under normal temperature and pressure.

It is a figure which shows the ammonia generation | occurence | production suppression apparatus used for the ammonia generation | occurence | production suppression method from the mortar concrete which concerns on 1st Embodiment of this invention. It is a figure which shows the relationship between the ammonia generation | occurrence | production speed | rate by the ammonia generation | occurence | production suppression method from the mortar concrete which concerns on 1st Embodiment of this invention, and elapsed days. It is a figure which shows the ammonia generation | occurence | production suppression apparatus used for the ammonia generation | occurence | production suppression method from the mortar concrete which concerns on 2nd Embodiment of this invention. It is a figure which shows the ammonia generation | occurence | production suppression apparatus used for the ammonia generation | occurrence | production suppression method from the mortar concrete which concerns on 3rd Embodiment of this invention. The figure shows the colored state when a phenolphthalein solution is sprayed on the split surface of mortar / concrete.

Explanation of symbols

1 Ammonia generation suppression device 2 Mortar / concrete (mortar / concrete components)
3 Chamber 4 Clean Air Generator 5 Impinger 5a Collected Liquid 6 Flowmeter 7 Mass Flow Meter 8 Pump 9 Gas Adsorbent 10 Activated Carbon 11 ULPA Filter 20 Ammonia Generation Suppressor 21 Vacuum Pump 30 Ammonia Generation Suppressor 31 Carbon Dioxide Supply Unit 32 Color development part

Claims (5)

A method for suppressing the generation of ammonia from mortar and concrete,
A predetermined amount of air corresponding to the surface area is forcibly sprayed on the surface of the mortar / concrete with a predetermined amount of air corresponding to the surface area of the mortar / concrete. A method for suppressing ammonia generation from mortar and concrete, wherein the ammonia is removed. A method for suppressing the generation of ammonia from mortar and concrete,
The mortar / concrete is contained in a chamber equipped with a clean air generating device having a gas adsorbent, activated carbon, and a ULPA filter, and the clean air that has passed through the clean air generating device is forcibly applied to the surface of the mortar / concrete. A method for suppressing the generation of ammonia from mortar / concrete comprising spraying to remove the ammonia in the mortar / concrete. A method for suppressing the generation of ammonia from mortar and concrete,
The ammonia generation from the mortar concrete according to claim 2 , wherein the mortar concrete is accommodated in the chamber, and the ammonia in the mortar concrete is removed by reducing the pressure in the chamber. Suppression method. A method for suppressing the generation of ammonia from mortar and concrete,
While containing the mortar concrete in a chamber and enclosing carbon dioxide in the chamber, the carbon dioxide is allowed to react with ammonia in the mortar concrete while invading from the surface of the mortar concrete, Converting the ammonia into carbonate ,
Depressurizing the chamber to promote the movement of the ammonia in the mortar concrete to the surface,
Further, forcibly spraying clean air that has passed through a clean air generating device equipped with a gas adsorbent, activated carbon and a ULPA filter on the surface of the mortar concrete to remove the ammonia in the mortar concrete. A method for suppressing ammonia generation from mortar and concrete. A mortar / concrete member used to construct a concrete structure,
A mortar / concrete member, which is treated by the method according to claim 1 to suppress generation of ammonia.

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