This work presents a simulation study of several Ca-Cu looping variants with CO(2)capture,aiming at both parameter optimization and exergy analysis of these Ca-Cu looping systems.Three kinds of Ca-Cu looping are consi...This work presents a simulation study of several Ca-Cu looping variants with CO(2)capture,aiming at both parameter optimization and exergy analysis of these Ca-Cu looping systems.Three kinds of Ca-Cu looping are considered:(1)carbonation-calcination/reduction-oxidation;(2)carbonation-oxidation-calcination/reduction and (3)carbona tion/oxidation-calcination/reduction.A conventional Ca looping is also simulated for comparison.The influences of the calcination temperature on the mole fractions of CO(2)and CaO at the calciner outlet,the CaCO3 flow rate on the carbonator performance and the Cu/Ca ratio on the calciner performance are analyzed.The second kind of Ca-Cu looping has the highest carbonation conversion.At 1×10^5 Pa and 820℃,complete decomposition of CaCO3 can be achieved in three Ca-Cu looping systems,while the operation condition of 1×10^5 Pa,840℃is required for the conventional Ca looping system.Furthermore,the Cu/Ca molar ratio of 5.13-5.19 is required for the Ca-Cu looping.Exergy analyses show that the maximum exergy destruction occurs in the calciner for the four modes and the second Ca-Cu looping system(i.e.,carbonation-oxidation-calcination/reduction)performs the highest exergy efficiency,up to 65.04%,which is about 30%higher than that of the conventional Ca looping.展开更多
实验表明,在烧制 Bi-Sr-Ca-Cu-O 超导体时,压片两面用银片覆盖后热处理有利于110K 超导相生成,制得的超导体有较高的零电阻温度。XPS 分析表明,在烧制超导材料时 Bi 能优先挥发,其次是 Ca。有银片覆盖可减轻 Bi 等成份的挥发程度,因此...实验表明,在烧制 Bi-Sr-Ca-Cu-O 超导体时,压片两面用银片覆盖后热处理有利于110K 超导相生成,制得的超导体有较高的零电阻温度。XPS 分析表明,在烧制超导材料时 Bi 能优先挥发,其次是 Ca。有银片覆盖可减轻 Bi 等成份的挥发程度,因此有银片覆盖的超导体中 Bi、Sr、Ca 和 O 的相对浓度比无银片覆盖的超导体中的要高。展开更多
The oxygen relief/absorption,superconduc— tivity and structure of(Bi_(1-x)Pb_x)_2Sr_2Ca_2— Cu_3O_y compounds have been studied by TGA, electrical resistance measurement and X-ray diffraction.The amount of oxygen whi...The oxygen relief/absorption,superconduc— tivity and structure of(Bi_(1-x)Pb_x)_2Sr_2Ca_2— Cu_3O_y compounds have been studied by TGA, electrical resistance measurement and X-ray diffraction.The amount of oxygen which can be re- leased and superconductivity of the compounds are correlative to Pb content.The release of oxygen in- creases when x less than 0.2 and decreases when x exceeds 0.2 with increasing x.The appropriate con- tent of Pb for superconductivity is in the range of 0.1<x<0.3,which corresponds to the relative large amount of oxygen that can be released.It is found according to electric resistance measurement that quenching is favourable to form the‘85K’phase and slow cooling the‘110K’phase.The experimen- tal results suggest that a relation exists between the superconductivity and the oxygen content in Bi sys- tem containing Pb.As the T_c of‘85K’phase de- creases and that of‘110K’phase increases with in- creasing oxygen content,it is possible that the effect of oxygen content in‘85K’phase and‘110K’ phase on the superconductivity is different.展开更多
Amorphous Bi(Pb)-Sr-Ca-Cu-O strips of types(1112)and(2212)were made by means of non-equilibrium solidification of melt-quenching method,On the surface of glassy strip,the flexible(2212)superconducting whiskers have be...Amorphous Bi(Pb)-Sr-Ca-Cu-O strips of types(1112)and(2212)were made by means of non-equilibrium solidification of melt-quenching method,On the surface of glassy strip,the flexible(2212)superconducting whiskers have been obtained.The growth and feature of superconducting whiskers were studied in detail.展开更多
The Bi-Sr-Ca-Cu-O suterconducting ceramics with T_c(onset)=112K, T_c(R=0)=85.3 K were prepared by quenching process.The Meissner effect of the sample appears at about 84.0 K.
基金financially supported by National Key R&D Program of China(2019YFE0100100)。
文摘This work presents a simulation study of several Ca-Cu looping variants with CO(2)capture,aiming at both parameter optimization and exergy analysis of these Ca-Cu looping systems.Three kinds of Ca-Cu looping are considered:(1)carbonation-calcination/reduction-oxidation;(2)carbonation-oxidation-calcination/reduction and (3)carbona tion/oxidation-calcination/reduction.A conventional Ca looping is also simulated for comparison.The influences of the calcination temperature on the mole fractions of CO(2)and CaO at the calciner outlet,the CaCO3 flow rate on the carbonator performance and the Cu/Ca ratio on the calciner performance are analyzed.The second kind of Ca-Cu looping has the highest carbonation conversion.At 1×10^5 Pa and 820℃,complete decomposition of CaCO3 can be achieved in three Ca-Cu looping systems,while the operation condition of 1×10^5 Pa,840℃is required for the conventional Ca looping system.Furthermore,the Cu/Ca molar ratio of 5.13-5.19 is required for the Ca-Cu looping.Exergy analyses show that the maximum exergy destruction occurs in the calciner for the four modes and the second Ca-Cu looping system(i.e.,carbonation-oxidation-calcination/reduction)performs the highest exergy efficiency,up to 65.04%,which is about 30%higher than that of the conventional Ca looping.
文摘实验表明,在烧制 Bi-Sr-Ca-Cu-O 超导体时,压片两面用银片覆盖后热处理有利于110K 超导相生成,制得的超导体有较高的零电阻温度。XPS 分析表明,在烧制超导材料时 Bi 能优先挥发,其次是 Ca。有银片覆盖可减轻 Bi 等成份的挥发程度,因此有银片覆盖的超导体中 Bi、Sr、Ca 和 O 的相对浓度比无银片覆盖的超导体中的要高。
文摘The oxygen relief/absorption,superconduc— tivity and structure of(Bi_(1-x)Pb_x)_2Sr_2Ca_2— Cu_3O_y compounds have been studied by TGA, electrical resistance measurement and X-ray diffraction.The amount of oxygen which can be re- leased and superconductivity of the compounds are correlative to Pb content.The release of oxygen in- creases when x less than 0.2 and decreases when x exceeds 0.2 with increasing x.The appropriate con- tent of Pb for superconductivity is in the range of 0.1<x<0.3,which corresponds to the relative large amount of oxygen that can be released.It is found according to electric resistance measurement that quenching is favourable to form the‘85K’phase and slow cooling the‘110K’phase.The experimen- tal results suggest that a relation exists between the superconductivity and the oxygen content in Bi sys- tem containing Pb.As the T_c of‘85K’phase de- creases and that of‘110K’phase increases with in- creasing oxygen content,it is possible that the effect of oxygen content in‘85K’phase and‘110K’ phase on the superconductivity is different.
文摘Amorphous Bi(Pb)-Sr-Ca-Cu-O strips of types(1112)and(2212)were made by means of non-equilibrium solidification of melt-quenching method,On the surface of glassy strip,the flexible(2212)superconducting whiskers have been obtained.The growth and feature of superconducting whiskers were studied in detail.
文摘The Bi-Sr-Ca-Cu-O suterconducting ceramics with T_c(onset)=112K, T_c(R=0)=85.3 K were prepared by quenching process.The Meissner effect of the sample appears at about 84.0 K.
