The increasing consumption of plastics inevitably results in increasing amounts of waste plastics. Because of their long degradation periods, these wastes negatively affect the natural environment. Numerous studies ha...The increasing consumption of plastics inevitably results in increasing amounts of waste plastics. Because of their long degradation periods, these wastes negatively affect the natural environment. Numerous studies have been conducted to recycle and eliminate waste plastics. The potential for recycling waste plastics in the iron and steel industry has been underestimated; the high C and H contents of plastics may make them suitable as alternative reductants in the reduction process of iron ore. This study aims to substitute plastic wastes for coal in reduction melting process and to investigate their performance during reduction at high temperature. We used a common type of waste plastic, polyethylene terephthalate （PET）, because of its high carbon and hydrogen contents. Composite pellets containing PET wastes, coke, and magnetite iron ore were reduced at selected temperatures of 1400 and 1450℃ for reduction time from 2 to 10 min to investigate the reduction melting behavior of these pellets. The results showed that an increased temperature and reduction time increased the reduction ratio of the pellets. The optimum experimental conditions for obtaining metallic iron （iron nuggets） were reduction at 1450℃ for 10 min using composite pellets containing 60% PET and 40% coke.展开更多
The cellulase expands the use of waste lignocellulosic and improves the feasibility of ethanol production with waste lignocellulosic. In this paper the types, mechanisms of cellulase and its application in reducing su...The cellulase expands the use of waste lignocellulosic and improves the feasibility of ethanol production with waste lignocellulosic. In this paper the types, mechanisms of cellulase and its application in reducing sugar production were presented in detail. The strains that produce cellulase and methods for improving the cellulase activity in reducing sugar production with waste lignocellulosic were described.展开更多
The common problem of cold strip continuous annealing furnaces is high exhaust gas temperature and great energy consumption. Taking the cold-strip continuous annealing furnaces of Baosteel No. 4 cold mill plant as an ...The common problem of cold strip continuous annealing furnaces is high exhaust gas temperature and great energy consumption. Taking the cold-strip continuous annealing furnaces of Baosteel No. 4 cold mill plant as an example, several waste heat recovery systems in the annealing furnaces are compared and their advantages and disadvantages are analyzed through different energy-saving technologies.展开更多
China should pilot renewable energy integration policies similar to those adopted in Germany and Texas in the Beijing-Tianjin-Hebei region to transmit excess energy and reduce wasted wind power.Renewable energy integr...China should pilot renewable energy integration policies similar to those adopted in Germany and Texas in the Beijing-Tianjin-Hebei region to transmit excess energy and reduce wasted wind power.Renewable energy integration will be fundamental to China?s transition to a low-carbon economy.Although China now leads the world in terms展开更多
Globally, about one third of all food produced is wasted every year. Losses take place along the entire food chain and they need to be analyzed and monitored due to their impact on the development of the food sector. ...Globally, about one third of all food produced is wasted every year. Losses take place along the entire food chain and they need to be analyzed and monitored due to their impact on the development of the food sector. In addition to quantitative losses, irrational use of food contributes to the depletion of natural resources （water and energy） and poses a threat to the environment, constituting a barrier to sustainable development of the food sector. The aim of this study was to establish the causes and effects of food waste throughout the food supply chain and to propose mitigation measures. Identified causes of food waste can be divided into two groups. The first are those that lead to the fact that food cannot be consumed （e.g., inadequate conditions of agricultural production and interruption of the cold chain）. In the second, those that cause food cannot be sold （e.g., wrong label and wrong product weight）. Most of the identified causes of food waste can be avoided （e.g., by improving the conditions of production, storage, and transportation）. However, it is not possible to eliminate all potential errors leading to food waste. It is therefore necessary to consider what action to take to use food as intended. One way to reduce losses and food waste can be re-distributing to charity.展开更多
Based on the analysis of actual energy consumptions during stevia sugar production,practical measures were proposed to save energy（ gas,water and powder） consumption and reduce cost through waste heat recycle and ut...Based on the analysis of actual energy consumptions during stevia sugar production,practical measures were proposed to save energy（ gas,water and powder） consumption and reduce cost through waste heat recycle and utilization,process improvement,equipment operation efficiency,application of newly energysaving equipment,and some project applications were provided as case study for some techniques and methods adopted in the production.展开更多
Oxidative-exfoliation methods were in vogue in the production of rGO from graphite.Processing of such synthetic graphite needs high temperatures(2500℃).Thus,such process is not cost-effective.The present study is mad...Oxidative-exfoliation methods were in vogue in the production of rGO from graphite.Processing of such synthetic graphite needs high temperatures(2500℃).Thus,such process is not cost-effective.The present study is made on the dry leaves of sugarcane(Saccharum officinarum)as an alternative raw material so as to be economical and environmentally benign.The dry leaves are subjected to two-step pyrolysis without any catalyst or reducing agent in far divergent temperatures to produce as prepared and acid treated rGOs.They were evaluated by UV–Vis.,FTIR,XRD,Raman spectroscopy,TGA/DTG,BET,FESEM-EDS and TEM.The as prepared rGO has few layers with irregular and folded architecture whereas acid-treated rGO has thinly stacked crumpled sheets with many wrinkles on its surface.The prepared rGOs have multilayered graphitic structure due to the unique ratio between G and D bands.Acid treated rGO has poor thermal stability as compared to that of as-prepared rGO at high temperatures due to the variation in the oxygen-containing functional groups.Acid treated rGO has low antibacterial activity as compared to that of the as-prepared rGO due to the paucity of the functional groups.展开更多
This review looks over the current construction and demolition waste management(C&DWM)situations by scrutinizing the definition,classification,components,compositions,generated sources and causes,impacts of genera...This review looks over the current construction and demolition waste management(C&DWM)situations by scrutinizing the definition,classification,components,compositions,generated sources and causes,impacts of generated construction and demolition wastes(C&DWs),waste management hierarchy(WMH),3R principles(Reduce,Reuse,and Recycle),Circular Economy(CE),frameworks,tools,and approaches of C&DWM.After reviewing the literature this study contributes to the literature by the following means:(a)suitable working definitions of C&DW and C&DWM are provided,(b)an expanded WMH for construction and demolition operations is presented,(c)frameworks of C&DWM are identified and listed as follows:frameworks based on WMH,including 3R principles and CE concept,frameworks focusing on the quantification,estimation,and prediction of generated C&DW,frameworks focusing on effective and sustainable C&DWM,frameworks focusing economic,social,and environmental performance assessment,frameworks based on multi-criteria analysis(MCA),frameworks based on post-disaster recovery period,and other miscellaneous frameworks,and(d)four categories of tools utilized in C&DWM are identified and explained,namely,approaches employed in C&DWM,information technology(IT)tools employed in C&DWM,multi-criteria decision analysis(MCDA)tools employed in C&DWM,and C&DWM technologies.Moreover,this study also found that CE,and green rating system(GRS)are widely used approaches,Building Information Modeling(BIM),Radio Frequency Identification(RFID),Geographic Information System,and Big Data are the extensively used IT tools,Analytical Hierarchy Process,FUZZY,TOPSIS(Technique for Order Preference by Similarity to the Ideal Solution),Weighted Summation,Elimination and Choice Expressing the Reality II,Elimination and Choice Expressing the Reality III,Evaluation of Mixed Data,and REGIME(REG)are the widely used MCA tools in C&DWM,and Prefabricated Construction and Modular Construction are broadly used C&DWM technologies.Furthermore,it has been observed that the application of the Analytic Networking Process(ANP)and hybridization of ANP,FUZZY,and TOPSIS tools do not catch considerable attention in the literature for conducting MCA,although it yields more precise outcomes.Additionally,most previous research has focused on the estimation of generated C&DW,but less attention has been given to forecasting the generated C&DW due to inadequate available C&DW data.This review article also assists C&DWM practitioners,academics,stakeholders,and contractors in choosing appropriate frameworks and tools for C&DWM while managing C&DW.展开更多
This article briefly discusses the theoretical basis and overall goals of energy conservation in the steel manufacturing process system.It is proposed that in the process of implementing system energy conservation,it ...This article briefly discusses the theoretical basis and overall goals of energy conservation in the steel manufacturing process system.It is proposed that in the process of implementing system energy conservation,it is necessary to fully recognize and utilize the characteristics and functional advantages of the steel manufacturing process,pay more attention to energy quality,firmly grasp the overall goal of system optimization,focus on the integrated optimization of gas,steam,and waste heat systems,and propose the idea of constructing a"steel chemi-cal gas electricity heating cooling multi generation system".Based on practice,the main principles,models,and effects of implementing systematic energy conservation in steel enterprises have been proposed.展开更多
基金financially supported by Yildiz Technical University Scientific Research Projects Coordination Department (No. 2011-07-02-KAP02)
文摘The increasing consumption of plastics inevitably results in increasing amounts of waste plastics. Because of their long degradation periods, these wastes negatively affect the natural environment. Numerous studies have been conducted to recycle and eliminate waste plastics. The potential for recycling waste plastics in the iron and steel industry has been underestimated; the high C and H contents of plastics may make them suitable as alternative reductants in the reduction process of iron ore. This study aims to substitute plastic wastes for coal in reduction melting process and to investigate their performance during reduction at high temperature. We used a common type of waste plastic, polyethylene terephthalate （PET）, because of its high carbon and hydrogen contents. Composite pellets containing PET wastes, coke, and magnetite iron ore were reduced at selected temperatures of 1400 and 1450℃ for reduction time from 2 to 10 min to investigate the reduction melting behavior of these pellets. The results showed that an increased temperature and reduction time increased the reduction ratio of the pellets. The optimum experimental conditions for obtaining metallic iron （iron nuggets） were reduction at 1450℃ for 10 min using composite pellets containing 60% PET and 40% coke.
文摘The cellulase expands the use of waste lignocellulosic and improves the feasibility of ethanol production with waste lignocellulosic. In this paper the types, mechanisms of cellulase and its application in reducing sugar production were presented in detail. The strains that produce cellulase and methods for improving the cellulase activity in reducing sugar production with waste lignocellulosic were described.
文摘The common problem of cold strip continuous annealing furnaces is high exhaust gas temperature and great energy consumption. Taking the cold-strip continuous annealing furnaces of Baosteel No. 4 cold mill plant as an example, several waste heat recovery systems in the annealing furnaces are compared and their advantages and disadvantages are analyzed through different energy-saving technologies.
文摘China should pilot renewable energy integration policies similar to those adopted in Germany and Texas in the Beijing-Tianjin-Hebei region to transmit excess energy and reduce wasted wind power.Renewable energy integration will be fundamental to China?s transition to a low-carbon economy.Although China now leads the world in terms
文摘Globally, about one third of all food produced is wasted every year. Losses take place along the entire food chain and they need to be analyzed and monitored due to their impact on the development of the food sector. In addition to quantitative losses, irrational use of food contributes to the depletion of natural resources （water and energy） and poses a threat to the environment, constituting a barrier to sustainable development of the food sector. The aim of this study was to establish the causes and effects of food waste throughout the food supply chain and to propose mitigation measures. Identified causes of food waste can be divided into two groups. The first are those that lead to the fact that food cannot be consumed （e.g., inadequate conditions of agricultural production and interruption of the cold chain）. In the second, those that cause food cannot be sold （e.g., wrong label and wrong product weight）. Most of the identified causes of food waste can be avoided （e.g., by improving the conditions of production, storage, and transportation）. However, it is not possible to eliminate all potential errors leading to food waste. It is therefore necessary to consider what action to take to use food as intended. One way to reduce losses and food waste can be re-distributing to charity.
文摘Based on the analysis of actual energy consumptions during stevia sugar production,practical measures were proposed to save energy（ gas,water and powder） consumption and reduce cost through waste heat recycle and utilization,process improvement,equipment operation efficiency,application of newly energysaving equipment,and some project applications were provided as case study for some techniques and methods adopted in the production.
文摘Oxidative-exfoliation methods were in vogue in the production of rGO from graphite.Processing of such synthetic graphite needs high temperatures(2500℃).Thus,such process is not cost-effective.The present study is made on the dry leaves of sugarcane(Saccharum officinarum)as an alternative raw material so as to be economical and environmentally benign.The dry leaves are subjected to two-step pyrolysis without any catalyst or reducing agent in far divergent temperatures to produce as prepared and acid treated rGOs.They were evaluated by UV–Vis.,FTIR,XRD,Raman spectroscopy,TGA/DTG,BET,FESEM-EDS and TEM.The as prepared rGO has few layers with irregular and folded architecture whereas acid-treated rGO has thinly stacked crumpled sheets with many wrinkles on its surface.The prepared rGOs have multilayered graphitic structure due to the unique ratio between G and D bands.Acid treated rGO has poor thermal stability as compared to that of as-prepared rGO at high temperatures due to the variation in the oxygen-containing functional groups.Acid treated rGO has low antibacterial activity as compared to that of the as-prepared rGO due to the paucity of the functional groups.
文摘This review looks over the current construction and demolition waste management(C&DWM)situations by scrutinizing the definition,classification,components,compositions,generated sources and causes,impacts of generated construction and demolition wastes(C&DWs),waste management hierarchy(WMH),3R principles(Reduce,Reuse,and Recycle),Circular Economy(CE),frameworks,tools,and approaches of C&DWM.After reviewing the literature this study contributes to the literature by the following means:(a)suitable working definitions of C&DW and C&DWM are provided,(b)an expanded WMH for construction and demolition operations is presented,(c)frameworks of C&DWM are identified and listed as follows:frameworks based on WMH,including 3R principles and CE concept,frameworks focusing on the quantification,estimation,and prediction of generated C&DW,frameworks focusing on effective and sustainable C&DWM,frameworks focusing economic,social,and environmental performance assessment,frameworks based on multi-criteria analysis(MCA),frameworks based on post-disaster recovery period,and other miscellaneous frameworks,and(d)four categories of tools utilized in C&DWM are identified and explained,namely,approaches employed in C&DWM,information technology(IT)tools employed in C&DWM,multi-criteria decision analysis(MCDA)tools employed in C&DWM,and C&DWM technologies.Moreover,this study also found that CE,and green rating system(GRS)are widely used approaches,Building Information Modeling(BIM),Radio Frequency Identification(RFID),Geographic Information System,and Big Data are the extensively used IT tools,Analytical Hierarchy Process,FUZZY,TOPSIS(Technique for Order Preference by Similarity to the Ideal Solution),Weighted Summation,Elimination and Choice Expressing the Reality II,Elimination and Choice Expressing the Reality III,Evaluation of Mixed Data,and REGIME(REG)are the widely used MCA tools in C&DWM,and Prefabricated Construction and Modular Construction are broadly used C&DWM technologies.Furthermore,it has been observed that the application of the Analytic Networking Process(ANP)and hybridization of ANP,FUZZY,and TOPSIS tools do not catch considerable attention in the literature for conducting MCA,although it yields more precise outcomes.Additionally,most previous research has focused on the estimation of generated C&DW,but less attention has been given to forecasting the generated C&DW due to inadequate available C&DW data.This review article also assists C&DWM practitioners,academics,stakeholders,and contractors in choosing appropriate frameworks and tools for C&DWM while managing C&DW.
文摘This article briefly discusses the theoretical basis and overall goals of energy conservation in the steel manufacturing process system.It is proposed that in the process of implementing system energy conservation,it is necessary to fully recognize and utilize the characteristics and functional advantages of the steel manufacturing process,pay more attention to energy quality,firmly grasp the overall goal of system optimization,focus on the integrated optimization of gas,steam,and waste heat systems,and propose the idea of constructing a"steel chemi-cal gas electricity heating cooling multi generation system".Based on practice,the main principles,models,and effects of implementing systematic energy conservation in steel enterprises have been proposed.
