Chen-Shan Kao

Hazard ratings for organic peroxides

Nine of commercially available organic peroxides were assessed with differential scanning calorimeter (DSC) and adiabatic calorimeters. These organic peroxides are cumene hydroperoxide (CHP), di‐tert‐butyl peroxide (DTBP), methyl‐ethyl‐ketone peroxide (MEKPO), tert‐butyl hydroperoxide (TBHP), benzoyl peroxide (BPO), hydrogen peroxide, lauroyl peroxide (LPO), tert‐butyl peroxybenzoate (TBPBZ), and dicumyl peroxide (DCPO). Exothermic onset temperatures, self‐heat temperature and pressure rates, and heats of decomposition were measured and assessed. Adiabatic runaway reaction characteristics were determined by using ARC (accelerating rate calorimeter) and VSP2 (vent sizing package). Incompatibility, tests with several potential contaminants, was made using DSC, VSP2, and microcalorimeter. An incompatibility rating was developed using onset temperature, lowering of the onset temperature, heat of decomposition, maximum self‐heat rate, adiabatic temperature rise, maximum pressure of decomposition, and maximum pressure rising rate, etc.

Safety Culture Factors, Group Differences, and Risk Perception in Five Petrochemical Plants

The purpose of this study was to develop and initially evaluate a survey to assess the level of present safety culture within a petrochemical organization. On the basis of the modified International Atomic Energy Agency (IAEA) safety culture model, we identified eight global dimensions of safety culture: safety commitment and support, safety attitude and behavior, safety communication and involvement, safety training and competence, safety supervision and audit, safety management system and organization, accident investigation and emergency planning, and reward and benefits. The 73‐item questionnaire, we developed, was distributed as a self‐administered survey to 604 workers of five petrochemical companies and 533 surveys were returned with a high response rate of 88.2%. Statistical methods were used to analyze the collected data sets, including factor analysis, t‐test, and one‐way ANOVA analysis of variance. Data indicated an overall positive performance in relation to organizational safety culture dimensions. Results also showed that personal backgrounds, particularly for job position, work experience, and age, significantly affected perceptions on many safety culture dimensions. In addition, specific factors revealed areas in need of organization attention for improvement, namely, safety commitment and support, safety communication and involvement, and rewards and benefits, were provided to senior managers for their use in decision making on promoting the safety culture within the organization.

Thermal stability of ethylene carbonate reacted with delithiated cathode materials in lithium-ion batteries

Confinement tests are implemented for measuring exothermic behaviors of eight delithiated or non-lithiated cathode materials mixed with ethylene carbonate (EC) which are commonly used in lithium-ion batteries. Eight delithiated and non-lithiated cathode materials, namely lithium cobalt oxide (LixCoO2), nickel oxide (NiO2), lithium nickel oxide (LixNiO2), lithium nickel cobalt oxide (LixNi0.8Co0.2O2), manganese oxide (Mn2O4), lithium manganese oxide (LixMn2O4), cobalt oxide (Co3O4) and iron phosphate (FePO4)are mixed with EC under a programmed rate of heating, respectively. Trajectories of temperature and pressure are measured simultaneously in the confined apparatus. Characteristics of thermal runaway such as onset temperature, maximum temperature, maximum pressure, maximum self-heat rate, etc., are assessed. The ranking of thermal stabilities of delithiated cathode and non-lithiated materials with EC is discussed and compared.

Trends in Major Incidents of Semiconductor-Related Industry in Taiwan

Reactive chemicals and combustible materials have led to numerous losses in semiconductor industry in Taiwan. Fifty nine incidents were collected and analyzed on related information to provide the integrated overviews of such events in the past thirteen years. Various types of factories either in the upstream or downstream of semiconductor industry were reviewed to deduce which kind of plant is feasible to possesses the higher risk of occurrence. Different kinds of chemicals or processes were compared with each other to verify the causes which led to the higher or largest loss already happened. Accidental fires caused by silane or flammable vapors are the dominant types of incidents in the semiconductor plant in comparison to any other types of materials. Besides, explosions, release of hazardous chemicals, and injuries by hazardous or corrosive chemicals are the three kinds of most common incidents encountered. Fire spread from the common exhaust duct or relief header always resulted in the largest loss among the reported events. The most serious lesson learnt from these losses was about three hundred million US dollars.