Copper-zinc alloy element for boiler energy saving was put in the intake of simulated boiler system to investigate the interaction and transfer of ions in water system both theoretically and experimentally.The fouling...Copper-zinc alloy element for boiler energy saving was put in the intake of simulated boiler system to investigate the interaction and transfer of ions in water system both theoretically and experimentally.The fouling was analyzed by scanning electron microscopy(SEM)and energy dispersive X-ray detector(EDX).The results show that the transfer of calcium and magnesium ions in heat-transfer-surface-water system is affected by zinc ions dissolved from the alloy because of primary battery reaction.Some calcium ions of calcium carbonate crystal are replaced by zinc ions,the growth of aragonite crystal nucleus is retarded,and the transition of calcium carbonate from aragonite to calcite is hampered.展开更多
Alkali recovery aiming at recovering NaOH is the best available technology in China's pulp and paper industry;an alkali recovery boiler is a popular one among all alkali recovery units. For the purpose of designin...Alkali recovery aiming at recovering NaOH is the best available technology in China's pulp and paper industry;an alkali recovery boiler is a popular one among all alkali recovery units. For the purpose of designing the most reasonable tube-panel of an evaporator in a 1500 t/d alkali recovery boiler, a total of 8 kinds of cases are put forward for finite element analysis. The modeling, meshing and calculation are carried out for each case. The stress values and their distribution rules are revealed in this paper. The slotting size for the water tubes panel is analyzed by using the optimum design module of ANSYS. After all cases are compared with each other, the optimal one is developed and exemplified in conclusion.展开更多
Cu-Zn,Cu-Zn-Sn,Cu-Zn-Ni alloys were melted by vacuum smelter.The effect factors to the surface free energy of the alloys such as chemical composition,crystal structure and surface crystal lattice distortion etc.were i...Cu-Zn,Cu-Zn-Sn,Cu-Zn-Ni alloys were melted by vacuum smelter.The effect factors to the surface free energy of the alloys such as chemical composition,crystal structure and surface crystal lattice distortion etc.were investigated by OCA30 automatic contact angle test instrument,metallography microscope and XRD instrument etc.Results suggests:adding alloy element to Cu may increase its surface free energy,and the more kinds of alloy elements are added,the more surface free energy increases;the alloy element Sn an increase the surface free energy of Cu-Zn alloy;Cu-Zn alloy with fir-tree crystal structure,great phase discrepancy and obvious composition aliquation has greater surface free energy;Cu-Zn alloy with compounds and serious surface crystal lattice distortion has greater surface free energy.展开更多
基金This work was financially supported by the Key Technologies R&D Program of Tianjin(No.06YFGZGX02400).
文摘Copper-zinc alloy element for boiler energy saving was put in the intake of simulated boiler system to investigate the interaction and transfer of ions in water system both theoretically and experimentally.The fouling was analyzed by scanning electron microscopy(SEM)and energy dispersive X-ray detector(EDX).The results show that the transfer of calcium and magnesium ions in heat-transfer-surface-water system is affected by zinc ions dissolved from the alloy because of primary battery reaction.Some calcium ions of calcium carbonate crystal are replaced by zinc ions,the growth of aragonite crystal nucleus is retarded,and the transition of calcium carbonate from aragonite to calcite is hampered.
文摘Alkali recovery aiming at recovering NaOH is the best available technology in China's pulp and paper industry;an alkali recovery boiler is a popular one among all alkali recovery units. For the purpose of designing the most reasonable tube-panel of an evaporator in a 1500 t/d alkali recovery boiler, a total of 8 kinds of cases are put forward for finite element analysis. The modeling, meshing and calculation are carried out for each case. The stress values and their distribution rules are revealed in this paper. The slotting size for the water tubes panel is analyzed by using the optimum design module of ANSYS. After all cases are compared with each other, the optimal one is developed and exemplified in conclusion.
基金This work was financially supported by the Key Technologies R&D Programme of Tianjin(06YFGZGX02400).
文摘Cu-Zn,Cu-Zn-Sn,Cu-Zn-Ni alloys were melted by vacuum smelter.The effect factors to the surface free energy of the alloys such as chemical composition,crystal structure and surface crystal lattice distortion etc.were investigated by OCA30 automatic contact angle test instrument,metallography microscope and XRD instrument etc.Results suggests:adding alloy element to Cu may increase its surface free energy,and the more kinds of alloy elements are added,the more surface free energy increases;the alloy element Sn an increase the surface free energy of Cu-Zn alloy;Cu-Zn alloy with fir-tree crystal structure,great phase discrepancy and obvious composition aliquation has greater surface free energy;Cu-Zn alloy with compounds and serious surface crystal lattice distortion has greater surface free energy.
