Polyethylene (PE) films with additives consisting mainly of oleic acid and ferrous ions were subjected to accelerated degradation at simulated composting temperatures.Based on Fourier transform infrared spectroscopy a...Polyethylene (PE) films with additives consisting mainly of oleic acid and ferrous ions were subjected to accelerated degradation at simulated composting temperatures.Based on Fourier transform infrared spectroscopy and measurements of mechanical properties and viscosity average molecular weight,the degradation of the films was characterized and the degradation mechanism was discussed.The films containing additives with ferrous ions represent considerable decreases in molecular weight,and the carbonyl groups and hydroperoxides in the aging films show different trends of increase with the aging time.These results indicate that the ferrous ion plays an important role in the degradation of PE films and accelerates the degradation of PE.展开更多
Delayed settling of the ash particles and poor drainage of water from the pond ash are the major problems faced during the hydraulic stowing of pond ash. In this study the effect of polymeric flocculant on settling of...Delayed settling of the ash particles and poor drainage of water from the pond ash are the major problems faced during the hydraulic stowing of pond ash. In this study the effect of polymeric flocculant on settling of the ash particles and drainage of water during pond ash stowing are investigated. In addition, the parameters, viz. drainage and absorption of water during pond ash stowing are quantified by stowing a mine goaf model with pond ash slurries of five different concentrations added with and without flocculant. The study revealed that addition of only 5 10 6 of Sodium Carboxymethyl Cellulose (Na-CMC) flocculant with the pond ash slurries during stowing offers best result in terms of quicker settling of the ash particles and enhanced water drainage from the hydraulically stowed pond ash. Besides, it resulted in drainage of more than 85% of the total water used in the initial 45 min of stowing. The improvement in drainage is caused due to coagulation and flocculation of the pond ash particles because of charge neutralization and particle-particle bridging. This study may provide a basis for estimating the drainage and absorption of water during the real pond ash stowing operation in underground mines.展开更多
文摘Polyethylene (PE) films with additives consisting mainly of oleic acid and ferrous ions were subjected to accelerated degradation at simulated composting temperatures.Based on Fourier transform infrared spectroscopy and measurements of mechanical properties and viscosity average molecular weight,the degradation of the films was characterized and the degradation mechanism was discussed.The films containing additives with ferrous ions represent considerable decreases in molecular weight,and the carbonyl groups and hydroperoxides in the aging films show different trends of increase with the aging time.These results indicate that the ferrous ion plays an important role in the degradation of PE films and accelerates the degradation of PE.
文摘Delayed settling of the ash particles and poor drainage of water from the pond ash are the major problems faced during the hydraulic stowing of pond ash. In this study the effect of polymeric flocculant on settling of the ash particles and drainage of water during pond ash stowing are investigated. In addition, the parameters, viz. drainage and absorption of water during pond ash stowing are quantified by stowing a mine goaf model with pond ash slurries of five different concentrations added with and without flocculant. The study revealed that addition of only 5 10 6 of Sodium Carboxymethyl Cellulose (Na-CMC) flocculant with the pond ash slurries during stowing offers best result in terms of quicker settling of the ash particles and enhanced water drainage from the hydraulically stowed pond ash. Besides, it resulted in drainage of more than 85% of the total water used in the initial 45 min of stowing. The improvement in drainage is caused due to coagulation and flocculation of the pond ash particles because of charge neutralization and particle-particle bridging. This study may provide a basis for estimating the drainage and absorption of water during the real pond ash stowing operation in underground mines.
