Based on the practice of magnesium production in China, a quantitative evaluation of the environment impact was carried out according to the theory and framework of life cycle assessment(LCA) study. The major gaseous ...Based on the practice of magnesium production in China, a quantitative evaluation of the environment impact was carried out according to the theory and framework of life cycle assessment(LCA) study. The major gaseous pollutants including CO2, SO2, NOx, CH4, HF and particulates were calculated. The accumulative environmental performances of different energy use strategies and the characterization results, including abiotic depletion potential(ADP), global warming potential(GWP), acidification potential(AP) and human-toxicity potential(HTP) were compared. The results show that the direct emission of fuel combustion in the process is the major contributor to the pollutants emission of magnesium production. Global warming potential and acidification potential make the main contribution to the accumulative environmental impact. The different fuel use strategies in the practice of magnesium production cause much different impacts on the environmental performance. The accumulative environmental impact of coal burned directly is the highest, and that of producer-gas comes to the next, while that of coke-oven gas is the lowest.展开更多
为明确燕麦的碳足迹特征,采用生命周期评价理论,对河北张家口、内蒙古乌兰察布和呼和浩特燕麦主产区58个农户及16家加工企业进行实地调研,对我国燕麦加工过程中的碳足迹进行了核算。结果表明,在燕麦种植环节,单位面积的碳足迹是800.29&#...为明确燕麦的碳足迹特征,采用生命周期评价理论,对河北张家口、内蒙古乌兰察布和呼和浩特燕麦主产区58个农户及16家加工企业进行实地调研,对我国燕麦加工过程中的碳足迹进行了核算。结果表明,在燕麦种植环节,单位面积的碳足迹是800.29±263.77 kg CO 2-eq·hm^-2,单位产量的碳足迹是0.380±0.125 t CO 2-eq·t^-1。其中,种植大户单位面积碳足迹为801.93±814.05 kg CO 2-eq·hm^-2,单位产量的碳足迹为0.380±0.386 t CO 2-eq·t^-1,接近于平均水平;种植散户单位面积的碳足迹为648.54±875.31 kg CO 2-eq·hm^-2,比燕麦种植平均水平低19.00%,单位产量碳足迹为0.422±0.570 t CO 2-eq·t^-1,比燕麦种植平均水平低11.10%。在燕麦加工环节,燕麦加工产品燕麦粉、燕麦片、燕麦米的单位质量碳足迹分别是69.67±5.77、130.62±10.86和50.76±4.81 kg CO 2-eq·t^-1。从燕麦食品全生命周期的角度分析,燕麦种植过程中的碳足迹显著低于玉米、水稻、小麦三大主粮作物,可以大面积种植。其中,燕麦种植散户的化肥用量和大户的灌溉电耗是燕麦种植环节碳足迹的主要来源。燕麦加工环节中燕麦片的碳足迹最大,主要因为燕麦片加工中需加热灭酶、汽蒸,涉及天然气的使用,能耗增加。因此,通过农户规模化种植、选择适合当地的节水灌溉技术,引导相关企业就近和适度加工、优化节能减排的技术等方法来减少碳足迹,促进燕麦产业的可持续发展。展开更多
基金Project(50525413) supported by the National Natural Science Foundation of ChinaProject(2006BAE04B09-6) supported by National Key Technology R&D Program
文摘Based on the practice of magnesium production in China, a quantitative evaluation of the environment impact was carried out according to the theory and framework of life cycle assessment(LCA) study. The major gaseous pollutants including CO2, SO2, NOx, CH4, HF and particulates were calculated. The accumulative environmental performances of different energy use strategies and the characterization results, including abiotic depletion potential(ADP), global warming potential(GWP), acidification potential(AP) and human-toxicity potential(HTP) were compared. The results show that the direct emission of fuel combustion in the process is the major contributor to the pollutants emission of magnesium production. Global warming potential and acidification potential make the main contribution to the accumulative environmental impact. The different fuel use strategies in the practice of magnesium production cause much different impacts on the environmental performance. The accumulative environmental impact of coal burned directly is the highest, and that of producer-gas comes to the next, while that of coke-oven gas is the lowest.
文摘为明确燕麦的碳足迹特征,采用生命周期评价理论,对河北张家口、内蒙古乌兰察布和呼和浩特燕麦主产区58个农户及16家加工企业进行实地调研,对我国燕麦加工过程中的碳足迹进行了核算。结果表明,在燕麦种植环节,单位面积的碳足迹是800.29±263.77 kg CO 2-eq·hm^-2,单位产量的碳足迹是0.380±0.125 t CO 2-eq·t^-1。其中,种植大户单位面积碳足迹为801.93±814.05 kg CO 2-eq·hm^-2,单位产量的碳足迹为0.380±0.386 t CO 2-eq·t^-1,接近于平均水平;种植散户单位面积的碳足迹为648.54±875.31 kg CO 2-eq·hm^-2,比燕麦种植平均水平低19.00%,单位产量碳足迹为0.422±0.570 t CO 2-eq·t^-1,比燕麦种植平均水平低11.10%。在燕麦加工环节,燕麦加工产品燕麦粉、燕麦片、燕麦米的单位质量碳足迹分别是69.67±5.77、130.62±10.86和50.76±4.81 kg CO 2-eq·t^-1。从燕麦食品全生命周期的角度分析,燕麦种植过程中的碳足迹显著低于玉米、水稻、小麦三大主粮作物,可以大面积种植。其中,燕麦种植散户的化肥用量和大户的灌溉电耗是燕麦种植环节碳足迹的主要来源。燕麦加工环节中燕麦片的碳足迹最大,主要因为燕麦片加工中需加热灭酶、汽蒸,涉及天然气的使用,能耗增加。因此,通过农户规模化种植、选择适合当地的节水灌溉技术,引导相关企业就近和适度加工、优化节能减排的技术等方法来减少碳足迹,促进燕麦产业的可持续发展。
