著者

山本 忠弘 阿曽 正登 清水 敏昭

出版者

日本火災学会

雑誌

日本火災学会論文集 (ISSN:05460794)

巻号頁・発行日

vol.34, no.1, pp.17-23, 1984 (Released:2012-07-04)

参考文献数

7

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It is well known that on addition of water onto a large amount of quick lime an exothermic reaction occurs and accumulated energy brings about a fire. However, even a small amount of desiccant for foods (about 110 g) brought about a fire in Himeji City of Hyogo Prefecture last year. Authors had interest in the fire caused by a desiccant and tried 47 ignition tests using desiccant (I) and quick lime in technical grades (II). The tests were carried out under conditions like the fire: Package of (I) or (II) was placed in sugar can (200 φ × 270 H) filled with a large volume of newspapers and tissue papers. Water was dropped into the opened package. 1) In 33 ignition tests for (II), ignition occurred 8 times and smoldering 10 times. The shortest time reached to ignition was 40 minutes and 34.6 ml of water was dropped for this period. The longest time was 90 minutes and 60 ml was dropped. When water was dropped at the rate of 0.5 - 0.9 ml/min in the range of these times and water amounts, the possibility reached to the ignition was high. 2) In 14 ignition tests for (I), smoldering occurred 4 times and smoke filled inner parts of the can. In the case of (I) having low calorific values such as less than 4 kcal/mol, smoke did not occur and the temperature did not rise to over than 200 °C. 3) Calorific values of (I) with water were 5 - 6 kcal/mol in average and less than 1/2 as compared to those of quick lime in 100% purity (determined value, 14.6) and in technical grades (11.9). The lowest one was 3.3 kcal/mol. 4) When the package included desiccant was immersed in water for 2 hours, about 70% of initial weight increased. The packing paper can pass fairly large amounts of water.