Study on thermal decomposition characteristics of AIBN.

It is found that the results such as observed in the differential scanning calorimeter (DSC), which show the major thermal decomposition (TD) of a self-reactive material, lack the detail to reveal what happens at the initial stage of a reaction. The reaction at this stage is corresponding to the handling condition of storage or transportation, often possibly having the potential to be developed to a runaway reaction. This paper examined and compared the thermal behaviors of AIBN at various working conditions in calorimeters and Dewar vessels.

Risk evaluation on the basis of pressure rate measured by automatic pressure tracking adiabatic calorimeter.

An automatic pressure tracking adiabatic calorimeter (APTAC) had been employed to obtain the thermokinetic and the vapor pressure data during runaway reactions. The APTAC is an adiabatic calorimeter with a large-scale sample mass and low thermal inertia, and is an extremely useful tool for assessing thermal hazards of reactive chemicals. The data obtained by the APTAC are important information for the design of the safe industrial process.

Risk assessment on processing facility of raw organic garbage.

To investigate the cause of an explosion during disposal processing of raw garbage, the property of the raw garbage was primarily examined by a thermo gravimetry-differential thermal analyzer. With mutable oil concentration, the results showed variable onset temperatures of the exothermal reaction for the samples, for example, decreasing from 150 degrees C in the samples typically containing 10.9-14.

Thermal characteristics of lysine tri-isocyanate and its mixture with water.

The thermal reactivity of lysine tri-isocyanate (LTI, 2-isocyanatoethyl-2,6-diisocyanato caproylate) and its mixture with 1% water was investigated after the occurrence of a runaway reaction at a plant. By using a sensitive thermal calorimeter, C80, and an adiabatic calorimeter, ARC, an onset reaction of LTI was observed at 70-100 degrees C and it became vigorous at 175-200 degrees C. The reaction is considered as co-polymerization at this stage, which causes a second decomposition reaction at 200 degrees C if the heat generation is accumulated in the vessel.

Evaluation of danger from fermentation-induced spontaneous ignition of wood chips.

Recently we conducted investigations in biological wastes because large pile-up storage of waste wood chips and others caused many fires in Japan. This paper shows the experimental results on wood chips with thermal analysis, by using a Thermogravimetry-differential thermal analysis (TG-DTA) and micro calorimeters, and as well with spontaneous ignition measurements, such as a UN wire mesh cube tester and a spontaneous ignition tester (SIT). Exothermic reaction of wood chips was observed during 45-60 degrees C only by the high sensitive microcalorimeters, TAM and MS 80.

Experimental determination of the minimum onset temperature of runaway reaction from a radioactive salt disposal in asphalt.

In order to clarify the reason for the most hazardous explosion in the history of the Japanese nuclear power development by a radioactive salt disposal in asphalt, an adiabatic process was developed using a Dewar vessel to minimize the temperature difference between the reactants and the surroundings. By this means, the heat evolution from a reaction which is readily lost can be detected at a lower temperature imitating the accidental condition. A series of ambient temperature-tracking Dewar experiments on asphalt salt mixtures were conducted under different initial ambient temperatures, such as 230, 210, 190, and 170 degrees C, respectively.

Decomposition of hydroxylamine/water solution with added iron ion.

Decomposition hazards of hydroxylamine (HA)/water solution with and without the addition of iron ion were studied in this paper. Tests were conducted to obtain information about decomposition hazards of HA/water solution following the United Nations recommendations on the transport of dangerous goods. When the heat accumulation storage test was conducted using HA50 wt.