以轻烧镁为原料,经消化、碳化、除杂、热解及煅烧制备出高纯氧化镁,并确定了适宜的工艺条件:活性炭用量为20 g/L,时间60 m in;活性炭吸附除杂温度20℃,时间80 m in;热解温度100℃,时间20 m in,升温速率均匀缓慢;煅烧温度950℃。氧化镁...以轻烧镁为原料,经消化、碳化、除杂、热解及煅烧制备出高纯氧化镁,并确定了适宜的工艺条件:活性炭用量为20 g/L,时间60 m in;活性炭吸附除杂温度20℃,时间80 m in;热解温度100℃,时间20 m in,升温速率均匀缓慢;煅烧温度950℃。氧化镁产品中氧化镁质量分数可达99.5%,氧化钙质量分数小于0.09%,铁的质量分数小于0.05%,产品中粒度小于5μm的粒子质量分数达到72.3%。SEM分析表明,低温热解氧化镁为针状,高温热解氧化镁为球状。展开更多
1.Introduction Carbon mitigation engineering,also known as climate engineering internationally,is an umbrella term of engineering measures targeted at combating climate change and achieving carbon neutrality.Climate o...1.Introduction Carbon mitigation engineering,also known as climate engineering internationally,is an umbrella term of engineering measures targeted at combating climate change and achieving carbon neutrality.Climate or mitigation engineering can be commonly divided into three categories based on technological principles[1]:(1)carbon dioxide removal(CDR),which has the potential to achieve negative emissions by removing atmospheric carbon dioxide[2].展开更多
To supply the valuable operating parameters for the popular usage of the new denitrifying phosphors removal process,it is essential to study the dominant biochemical reactions and the characteristics of denitrifying p...To supply the valuable operating parameters for the popular usage of the new denitrifying phosphors removal process,it is essential to study the dominant biochemical reactions and the characteristics of denitrifying phosphorus removing bacteria(DPB).Thus,parallel batch experiments using DPB sludge were carried out to assess the effect of substrates(sewage,HAc,and endogenous carbon source)on denitrifying dephosphorus removal efficiency in this study.The results showed that the initial specific phosphorus release rate increased with the high concentration of the short-chain volatile fatty acids ratio in the influent,and sufficient phos-phorus was released by DPB.This improved the subsequent denitrification and phosphorus uptake efficiency.The specific endogenous denitrification mainly relies on the internal carbon source(PHB)stored by poly-P bacteria.Denitrifying phosphorus removing bacteria were very hungry when the internal PHB was consumed.Consequently,the specific endogenous denitrification rate was low and the phosphorus uptake did not happen.On the other hand,in the experiment,the denitrifying phosphorus removal performance under two temperature conditions(8-10°C and 25-26°C)was also investigated and analyzed.It was found that the lower temperature decreased the specific phosphorus release and uptake rate,but did not inhibit the denitrifying phosphorus removal completely.Therefore,the negative influence of the low temperature on the overall phosphorus removal was not significant.展开更多
文摘以轻烧镁为原料,经消化、碳化、除杂、热解及煅烧制备出高纯氧化镁,并确定了适宜的工艺条件:活性炭用量为20 g/L,时间60 m in;活性炭吸附除杂温度20℃,时间80 m in;热解温度100℃,时间20 m in,升温速率均匀缓慢;煅烧温度950℃。氧化镁产品中氧化镁质量分数可达99.5%,氧化钙质量分数小于0.09%,铁的质量分数小于0.05%,产品中粒度小于5μm的粒子质量分数达到72.3%。SEM分析表明,低温热解氧化镁为针状,高温热解氧化镁为球状。
基金financial support from the National Natural Science Foundation of China(71521002)National Key Research and Development Program of China(2016YFA0602603)。
文摘1.Introduction Carbon mitigation engineering,also known as climate engineering internationally,is an umbrella term of engineering measures targeted at combating climate change and achieving carbon neutrality.Climate or mitigation engineering can be commonly divided into three categories based on technological principles[1]:(1)carbon dioxide removal(CDR),which has the potential to achieve negative emissions by removing atmospheric carbon dioxide[2].
基金This work was supported by the National Natural Science Foundation of China(Grant No.50608064 and 50138010)the Natural Science Foundation of Zhejiang Province(Grant No.Y505031)the China Postdoctoral Science Foundation(Grant No.2005037296).
文摘To supply the valuable operating parameters for the popular usage of the new denitrifying phosphors removal process,it is essential to study the dominant biochemical reactions and the characteristics of denitrifying phosphorus removing bacteria(DPB).Thus,parallel batch experiments using DPB sludge were carried out to assess the effect of substrates(sewage,HAc,and endogenous carbon source)on denitrifying dephosphorus removal efficiency in this study.The results showed that the initial specific phosphorus release rate increased with the high concentration of the short-chain volatile fatty acids ratio in the influent,and sufficient phos-phorus was released by DPB.This improved the subsequent denitrification and phosphorus uptake efficiency.The specific endogenous denitrification mainly relies on the internal carbon source(PHB)stored by poly-P bacteria.Denitrifying phosphorus removing bacteria were very hungry when the internal PHB was consumed.Consequently,the specific endogenous denitrification rate was low and the phosphorus uptake did not happen.On the other hand,in the experiment,the denitrifying phosphorus removal performance under two temperature conditions(8-10°C and 25-26°C)was also investigated and analyzed.It was found that the lower temperature decreased the specific phosphorus release and uptake rate,but did not inhibit the denitrifying phosphorus removal completely.Therefore,the negative influence of the low temperature on the overall phosphorus removal was not significant.