In this paper we address the topic of energy and water optimization in the production of bioethanol from corn and switchgrass. We show that in order for these manufacturing processes to be attractive,there is a need t...In this paper we address the topic of energy and water optimization in the production of bioethanol from corn and switchgrass. We show that in order for these manufacturing processes to be attractive,there is a need to go beyond traditional heat integration and water recycling techniques. Thus,we propose a strategy based on mathe-matical programming techniques to model and optimize the structure of the processes,and perform heat integration including the use of multi-effect distillation columns and integrated water networks to show that the energy effi-ciency and water consumption in bioethanol plants can be significantly improved. Specifically,under some circum-stances energy can even be produced and the water consumption can be reduced below the values required for the production of gasoline.展开更多
Potentials range is determined in which the cobalt-tungsten alloy phase selectively dissolved in solutions of phosphoric acid to form soluble compounds of these metals, while the tungsten carbide phase remains in the ...Potentials range is determined in which the cobalt-tungsten alloy phase selectively dissolved in solutions of phosphoric acid to form soluble compounds of these metals, while the tungsten carbide phase remains in the precipitate. It shows that tungsten ores and concentrates are decomposed at 1,050℃-1,100℃ in sodium chloride-sodium metasilicate melts to form two immiscible phases, namely, halide-tungstate, containing 96% to 99% of tungsten, and silicate, containing 90% of the rest ore components.展开更多
A burnup calculation has been performed to evaluate heavy rare earth （terbium--Tb, dysprosium--Dy） production in spent gadolinium oxide （Gd203） installed as a BP （burnable poison）. Each amount of Tb and Dy produ...A burnup calculation has been performed to evaluate heavy rare earth （terbium--Tb, dysprosium--Dy） production in spent gadolinium oxide （Gd203） installed as a BP （burnable poison）. Each amount of Tb and Dy production derived from the BP has been about 30-40 times larger than those created in FP （fission products）. Required cooling time to achieve exemption level on radioactivity concentration produced Tb and Dy derived from the BP are much shorter （BP-Tb： 7.9y, BP-Dy： 〈 0.1y） than those created in FP （FP-Tb： 3,616y, FP-Dy： 6.9y）. However, the BP is mixed homogeneously with UO2 pellet in current nuclear fuel system of LWRs （light water reactors）, and hence mixing of FP cannot be not avoided. In such a mixture case, the required cooling time of recovered Tb will become 2,653y and that of recovered Dy be 4.8y. For this reason, recovered Tb is unlikely to be resource for utilization, while recovered Dy must be the resource provided the precise separation from the other FP.展开更多
This work consists of estimating the energy achieved from all land and water-based vegetations. This real potential is determined by identifying 10 biomass samples taken from vegetable resources which are favored by t...This work consists of estimating the energy achieved from all land and water-based vegetations. This real potential is determined by identifying 10 biomass samples taken from vegetable resources which are favored by their aptitude of adaptation to the conditions of Iran. The net energy values of the 10 biomass samples change in the range of 13.65-18.00 MJ/kg using bomb calorimeter. By means of least squarere regression method all correlations were found. The results of 10 different biomass materials have been used to develop a linear equation correlation.展开更多
Green supply chain is one of the trends of industry development. And performance measurement is the key to implementing the supply chain. So it is necessary to evaluate the environmental performance of supply chain .A...Green supply chain is one of the trends of industry development. And performance measurement is the key to implementing the supply chain. So it is necessary to evaluate the environmental performance of supply chain .According to the connotation of green supply chain and the standards of environmental management, this paper designs green performance measurement systems which is composed of four main factors such as waste emissions and exposure hazard, resource utilization, product recovery, and environmental reputation. And the authors delve deeply these factors so that it forms a two-level measurement system. Then the effect on the traditional performance measurement of supply chain is studied after taking greening to the supply chain leveL At last the authors apply the method of multi-level fuzzy judgment to the environmental performance measurement system. An example is given to show the judgment process.展开更多
基金the Center for Advanced Process Decision-making at Carnegie Mellon University and NSF Grant CBET096654
文摘In this paper we address the topic of energy and water optimization in the production of bioethanol from corn and switchgrass. We show that in order for these manufacturing processes to be attractive,there is a need to go beyond traditional heat integration and water recycling techniques. Thus,we propose a strategy based on mathe-matical programming techniques to model and optimize the structure of the processes,and perform heat integration including the use of multi-effect distillation columns and integrated water networks to show that the energy effi-ciency and water consumption in bioethanol plants can be significantly improved. Specifically,under some circum-stances energy can even be produced and the water consumption can be reduced below the values required for the production of gasoline.
文摘Potentials range is determined in which the cobalt-tungsten alloy phase selectively dissolved in solutions of phosphoric acid to form soluble compounds of these metals, while the tungsten carbide phase remains in the precipitate. It shows that tungsten ores and concentrates are decomposed at 1,050℃-1,100℃ in sodium chloride-sodium metasilicate melts to form two immiscible phases, namely, halide-tungstate, containing 96% to 99% of tungsten, and silicate, containing 90% of the rest ore components.
文摘A burnup calculation has been performed to evaluate heavy rare earth （terbium--Tb, dysprosium--Dy） production in spent gadolinium oxide （Gd203） installed as a BP （burnable poison）. Each amount of Tb and Dy production derived from the BP has been about 30-40 times larger than those created in FP （fission products）. Required cooling time to achieve exemption level on radioactivity concentration produced Tb and Dy derived from the BP are much shorter （BP-Tb： 7.9y, BP-Dy： 〈 0.1y） than those created in FP （FP-Tb： 3,616y, FP-Dy： 6.9y）. However, the BP is mixed homogeneously with UO2 pellet in current nuclear fuel system of LWRs （light water reactors）, and hence mixing of FP cannot be not avoided. In such a mixture case, the required cooling time of recovered Tb will become 2,653y and that of recovered Dy be 4.8y. For this reason, recovered Tb is unlikely to be resource for utilization, while recovered Dy must be the resource provided the precise separation from the other FP.
文摘This work consists of estimating the energy achieved from all land and water-based vegetations. This real potential is determined by identifying 10 biomass samples taken from vegetable resources which are favored by their aptitude of adaptation to the conditions of Iran. The net energy values of the 10 biomass samples change in the range of 13.65-18.00 MJ/kg using bomb calorimeter. By means of least squarere regression method all correlations were found. The results of 10 different biomass materials have been used to develop a linear equation correlation.
文摘Green supply chain is one of the trends of industry development. And performance measurement is the key to implementing the supply chain. So it is necessary to evaluate the environmental performance of supply chain .According to the connotation of green supply chain and the standards of environmental management, this paper designs green performance measurement systems which is composed of four main factors such as waste emissions and exposure hazard, resource utilization, product recovery, and environmental reputation. And the authors delve deeply these factors so that it forms a two-level measurement system. Then the effect on the traditional performance measurement of supply chain is studied after taking greening to the supply chain leveL At last the authors apply the method of multi-level fuzzy judgment to the environmental performance measurement system. An example is given to show the judgment process.
