Study on the effect of thermal property of powder on the gas explosion suppression

The decomposition experiments of Al(OH)(3), Mg(OH)(2) and Urea were conducted by TG and DSC. The thermal characteristics of powders were obtained. It shows that pyrolysis temperature of Urea (133 degrees C) was lower than that of Al(OH)(3) and Mg(OH)(2), and its heat absorption (1291J/g) was larger than Al(OH)(3) and Mg(OH)(2). Suppression mechanisms of gas explosion were analyzed and compared. The results showed the performance of Urea was better than that of the other two materials because of Urea's faster decomposition rate, greater heat absorption and more free radical generated during the period of decomposition process. Also the suppression performance of Urea was confirmed by the gas explosion experiments. (C) 2011 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of China Academy of Safety Science and Technology, China University of Mining and Technology(Beijing), McGill University and University of Wollongong.