Simple removal of dioxins by injecting combustion gas into water

A simple, low-cost method for suppression of dioxins/furans (hereinafter referred to as dioxins) is required because many middle- and, especially, small-scale incinerators have fallen into disuse or have been dismantled because of the high running and system costs of measures for the suppression of dioxins. Therefore, the purpose of the present study was to develop a simple removal method for dioxins from combustion gas and to evaluate the basic removal rate of dioxins. The removal method for suspended matter in a gas mixture (cold model) and dioxins in exhaust gases (hot model) has been investigated by means of gas injection into water, the mechanism of which is that the suspended matter in the gas gathers at the gas–liquid interface. In the cold model, the removal ratio of fine particles (R_P) by gas injection into water was reproduced well by the following equation: R_P (%) = 100 × {1−exp(−0.8 · S_S · t_C)}, where S_S (cm²/cm³) is the specific surface area of bubbles and t_C (s) is the residence time of bubbles in water. The removal ratio of fine particles increased as the product S_s · t_C increased. In a hot model using the exhaust gas from combustion experiments of polyvinyl chloride, the removal ratio of dioxins (R_D) by injecting the exhaust gas into water was estimated by the following equation: R_D (%) = 100 × {1−exp(−0.8 · S_S · t_C · C_D0 ^0.07)}, where C_D0 [ng/cm³ (at standard temperature and pressure)] is the dioxins concentration in the exhaust gas before injection into water. R_D depends greatly on the specific surface area of bubbles and the residence time of the bubbles in water, and only weakly on the dioxins concentration in the exhaust gas. Injection of the exhaust gas into water has been shown to be effective and was evaluated as a simple method for the removal of dioxins from exhaust gas.     

New biofidelic corridor and biofidelity test procedure for pedestrian legform impactors

The objectives of this research are to propose a new impact response corridor for the ISO legform impactor and to determine the biofidelity of the current legform impactor with rigid leg and thigh developed by the Transport Research Laboratory (TRL). The latest data obtained from Post Mortem Human Subject (PMHS) knee impact tests were analyzed in connection with the proposal, and biofidelity legform impact tests were conducted using the current rigid legform impactor. New normalized biofidelic corridors of impact force corresponding to adult male 50th percentile (AM50) are proposed. The impact test results indicate the current rigid legform impactor does not have sufficient human knee biofidelity. The present results suggest that human tolerance can not be used directly for the injury reference value of the legform impactor. A conversion method is needed to interpret the data measured by current legform impactors as the injury reference value.