The southern margin of the Gurbantunggut Desert,China,is characterized by alternating layers of aeolian and alluvial deposits.Investigating the characteristics of arenaceous sediment in this area is of significant imp...The southern margin of the Gurbantunggut Desert,China,is characterized by alternating layers of aeolian and alluvial deposits.Investigating the characteristics of arenaceous sediment in this area is of significant importance for understanding the interactive processes of wind and water forces,as well as the provenance of sediment.However,there are relatively few investigations on the characteristics of such sediment at present.In this study,we researched three aeolian-alluvial interactive stratigraphic profiles and different types of surface sediment on the desert-oasis transitional zone of southern margin of the Gurbantunggut Desert.Based on the optically stimulated luminescence(OSL)dating of aeolian sand and analyses of quartz sand grain size and surface micro-texture,we explored the aeolian-alluvial environmental change at southern margin of the desert in Holocene,as well as the provenance of sediment.The results indicated that the grain size characteristics of different types of sediment in the stratigraphic profiles were similar to those of modern dune sand,interdune sand,muddy desert surface soil,and riverbed sand.Their frequency curves were unimodal or bimodal,and cumulative probability curves were two-segment or three-segment,mainly composed of suspension load and saltation load.The quartz sand in the sediment at southern margin of the desert had undergone alternating transformation of various exogenic forces,with short transportation distance and time,and sedimentary environment was relatively humid.In Holocene,southern margin of the desert primarily featured braided river deposits,and during intermittent period of river activity,there were also aeolian deposits such as sand sheet deposits,stabilized dune deposits,and mobile dune deposits.The provenance for Holocene alluvial deposits at southern margin of the desert remains relatively constant,with the debris of the Tianshan Mountains being the primary provenance.Aeolian sand is mainly near-source recharge,which is formed by in situ deposition of fluvial or lacustrine materials in southern margin of the desert transported by wind erosion,and its provenance was still the weathered debris of the Tianshan Mountains.In addition,the sand in interior of the desert may be transported by northwest wind in desert-scale,thus affecting the development of dunes in southern margin of the desert.The results of this study provide a reference for understanding the composition and provenance changes of desert sand in the context of global climate change.展开更多
转炉煤气是钢厂生产钢铁过程中副产的CO体积分数为60%的尾气,通常被直接排放或作为燃料使用,造成环境污染与资源浪费。本文提出了利用转炉煤气合成草酸二甲酯(DMO)的工艺过程,主要处理单元包括加氢脱硫、催化除氧、低温甲醇洗与DMO合成...转炉煤气是钢厂生产钢铁过程中副产的CO体积分数为60%的尾气,通常被直接排放或作为燃料使用,造成环境污染与资源浪费。本文提出了利用转炉煤气合成草酸二甲酯(DMO)的工艺过程,主要处理单元包括加氢脱硫、催化除氧、低温甲醇洗与DMO合成。通过使用Aspen Plus V10化工模拟软件对工艺进行模拟计算、质量能量分析与技术经济分析。结果显示该工艺生产的DMO价格为5309.74元/t,低于目前市场价格(10000元/t);内部收益率为35.56%,大于基本贴现率(12%).盈亏平衡分析显示当生产负荷超过24.94%时,项目开始盈利。本文设计的工艺过程具有很好的经济效益,为实现转炉煤气的资源化利用、钢铁企业的节能减排提供建议与思路。展开更多
基金the National Natural Science Foundation of China(42071011)the 2023 Annual Postgraduate Research and Innovation Foundation of Fujian Normal University,China.
文摘The southern margin of the Gurbantunggut Desert,China,is characterized by alternating layers of aeolian and alluvial deposits.Investigating the characteristics of arenaceous sediment in this area is of significant importance for understanding the interactive processes of wind and water forces,as well as the provenance of sediment.However,there are relatively few investigations on the characteristics of such sediment at present.In this study,we researched three aeolian-alluvial interactive stratigraphic profiles and different types of surface sediment on the desert-oasis transitional zone of southern margin of the Gurbantunggut Desert.Based on the optically stimulated luminescence(OSL)dating of aeolian sand and analyses of quartz sand grain size and surface micro-texture,we explored the aeolian-alluvial environmental change at southern margin of the desert in Holocene,as well as the provenance of sediment.The results indicated that the grain size characteristics of different types of sediment in the stratigraphic profiles were similar to those of modern dune sand,interdune sand,muddy desert surface soil,and riverbed sand.Their frequency curves were unimodal or bimodal,and cumulative probability curves were two-segment or three-segment,mainly composed of suspension load and saltation load.The quartz sand in the sediment at southern margin of the desert had undergone alternating transformation of various exogenic forces,with short transportation distance and time,and sedimentary environment was relatively humid.In Holocene,southern margin of the desert primarily featured braided river deposits,and during intermittent period of river activity,there were also aeolian deposits such as sand sheet deposits,stabilized dune deposits,and mobile dune deposits.The provenance for Holocene alluvial deposits at southern margin of the desert remains relatively constant,with the debris of the Tianshan Mountains being the primary provenance.Aeolian sand is mainly near-source recharge,which is formed by in situ deposition of fluvial or lacustrine materials in southern margin of the desert transported by wind erosion,and its provenance was still the weathered debris of the Tianshan Mountains.In addition,the sand in interior of the desert may be transported by northwest wind in desert-scale,thus affecting the development of dunes in southern margin of the desert.The results of this study provide a reference for understanding the composition and provenance changes of desert sand in the context of global climate change.
文摘转炉煤气是钢厂生产钢铁过程中副产的CO体积分数为60%的尾气,通常被直接排放或作为燃料使用,造成环境污染与资源浪费。本文提出了利用转炉煤气合成草酸二甲酯(DMO)的工艺过程,主要处理单元包括加氢脱硫、催化除氧、低温甲醇洗与DMO合成。通过使用Aspen Plus V10化工模拟软件对工艺进行模拟计算、质量能量分析与技术经济分析。结果显示该工艺生产的DMO价格为5309.74元/t,低于目前市场价格(10000元/t);内部收益率为35.56%,大于基本贴现率(12%).盈亏平衡分析显示当生产负荷超过24.94%时,项目开始盈利。本文设计的工艺过程具有很好的经济效益,为实现转炉煤气的资源化利用、钢铁企业的节能减排提供建议与思路。