23 research outputs found

    Cause and Countermeasure Way of Rubble Fires Occurred after 2011 Great Earthquake of Japan

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    AbstractThis paper seeks for cause and countermeasure way of fires of huge amount of rubble which were produced after 2011 great earthquake of Japan. In 2011, we experienced many fires caused with rubbles which were produced from destroyed houses by the Great earthquake and tsunami in March 11, 2011, in Japan. Rubble includes various organic materials, and sometimes causes fires, which is used for fuel of power plants, or energy sources. It is very difficult to extinguish fire of such biomass fuel made from rubble in outdoor storage facilities. Here current studies for safety handling of these materials and proposed an evaluation method, is introduced, which is to use high sensitive calorimeters. And cause investigation work and countermeasure method, conducted by author is introduced. Our results regarding cause of fires are: initial of heat generation and fire are mostly by fermentation, and then oxidation process started after micro organism dead by high temperature, up to about 60°C. High sensitive calorimeters can detect small heat generation between room temperature and 80°C, due to fermentation or other causes. This heat generation sometimes initiated a real fire even outdoor, and produced some combustible gas. With understanding this process we recommend countermeasure way against such fires, to release heat from the pile, and prevent air entrainment into the pile to stop fermentation

    エヒメケン マツヤマ フキン ノ コウマグネシア アンザンガン ニ ホウユウ サレル チョウエンキセイ ガンルイ ノ ヘンケイ ヨウシキ

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    Ultramafic inclusions were found in high magnesian andesite at Dogo, Matsuyama City, Ehime Prefecture, Southwest Japan. They are classified into two types, from the texture and chemical composition of minerals ; type-1 and type-2. Type-1 inclusion is harzburgite, characterized by the presence of Al-rich spinel. Type-2 inclusion is composed of dunite and harzburgite, with Cr-rich spinel. Olivine fabric patterns of the inclusions exhibit high concentration of X and Z axes, which differ from those of cumulate rocks. It seems that the textural development of the inclusions occurred through deformation process. Petrographical evidence supports this. Dislocation structure of olivine from the inclusion was examined. The dislocation density of olivines for type-2 inclusion falls into the range of 1×10^7 to 5×10^7cm^ . The subgrain size of olivines from type-1 and type-2 inclusion has narrow range from 20 to 35μm. Considering the rate of stress-responce of dislocation density, subgrain size and grain size, it is concluded that type-1 inclusion deformed in nearly steady-state creep, whereas type-2 inclusion deformed in transient creep

    オカヤマケン ナンブ ノ フウカ カコウガン チュウ ノ ネンド コウブツソノ1 カサオカシ キタギジマ ニ ツイテ

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    The constituent clay minerals of the weathered granites (saprolite), veins, and fractures in the Sanyo-type granitic body, and the vein in the Ryoke-type granitic body of Kitagi Island, Okayama Prefecture, have been examined by X-ray powder diffraction. The saprolite contains halloysite, vermiculite, and a small amount of kaolinite. The clay vein mainly consists of halloysite and a small amount of kaolinite, vermiculite, and di-octahedral smectite in the Sanyo-type granite, and kaolinite and vermiculite in the Ryoke-type granite. In the fracture, commonest clay mineral is di-octahedral smectite with subordinate amounts of halloysite and kaolinite. Mica clay mineral is found in all cases. The clay minerals in the saprolite were formed during the chemical weathering. On the other hand, it seems that the clay minerals in the veins and fractures are hydrothermal origin and remain unchanged through weathering

    ミズノコイワ カラ ハッケン サレタ ビゼンヤキ

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    The sintering process of a broken piece of Bizen-yaki vase discovered in Mizunoko-iwa and its components were studied by means of X-ray diffraction and electron microscopy. The components of the sample discovered in Mizunoko-iwa were mainly mullite, cristobalite, quartz and feldspar. Quartz and feldspar were much contained in it, compared with Bizen-yaki of recent days. It is considered that the sintering process was similar to the process now in current. As a result of electron microscopy, the needle-shaped and thin crystal were observed in the sample above mentioned. The formation of needle-shaped crystal was considered to be due to the reaction with the sea water. The Bizen-yaki vases in Mizunoko-iwa were generally porous and raw materials were comparatively rough

    Investigation of Accidents during Storage Caused by Fermentation or Oxidation from SSSR and Fishmeal Using Thermal Analysis and Frank-Kamenetskii Theory

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    In Japan, where soy sauce production and the fishery industries thrive, soy sauce squeezing residue (SSSR) and fishmeal, which are operational byproducts of these sectors, are produced as waste materials for recycling. SSSR and fishmeal have resulted in accidents due to spontaneous ignition and oxygen deprivation, which are believed to have been caused by the heat generated through fermentation or oxidation; consequently, it is desirable to develop measures that prevent such accidents during storage and transportation. In this study, we assessed the hazards associated with the spontaneous ignition and oxygen deprivation of SSSR and fishmeal in storage areas using thermal and gas analysers, focusing on the heat produced by fermentation and oxidation. We also used Frank-Kamenetskii theory to determine the relationship between pile height and the ambient temperatures at which spontaneous ignition and oxygen deprivation occur. Our results suggest that oxygen deficiency may occur in a well-sealed storage facility in which oxygen is consumed by fermentation. For example, the oxygen concentration can drop below critical safety thresholds in the case of SSSR, even when stored below 25 °C, particularly when the moisture content is high. However, when a sufficient amount of oxygen is present and the material is stored in large deposits in a well-insulated facility, fermentation causes the temperature to increase, leading to the oxidation of fatty acid esters and eventually fire; when SSSR or fishmeal is maintained at temperatures near 40 °C, their temperatures can increase to 250 °C within approximately 30 h. Furthermore, the results of this study also demonstrate the need to consider pile height in storage areas in order to prevent accidents due to spontaneous ignition and oxygen deprivation; the critical ambient temperature at which heat accumulates is estimated to be between 20–30 °C, at a bulk density of 0.3 × 103 kg/m3, and a pile height of 3 m

    ケイソウド カラノ トバモライト ノ ゴウセイ オカヤマケン ヒルゼンサン ケイソウド ノ ユウコウ リヨウ ニ カンスル ケンキュウ ダイ1ホウ

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    In order to develope the effective industrial usage, the diatomaceous earth from Hiruzen district was treated hydrothermally with calcium oxide on various Ca (in calcium oxide)/Si+Al (in diatomaceous earth) ratios of 0.3,0.5,1.0,2.0 and 3.0 at temperatures of 150° and 200℃ under saturated water vapor pressures. The products were examined by means of X-ray diffraction and scanning electron microscopy. As a result, it was found that well crystallized 11A-tobermorite can be obtained at Ca/Si+Al ratios of 0.5 and 1.0 on the treatment for more than 12 hours, while CSH (I) can be formed in other experimental conditions
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