To efficiently co-extract Ni and Cu from low-grade nickel-copper sulfide ore,chlorination roasting with NH;Cl followed by a water leaching process was investigated.The results show that 98.4%Ni and 98.5%Cu can be sync...To efficiently co-extract Ni and Cu from low-grade nickel-copper sulfide ore,chlorination roasting with NH;Cl followed by a water leaching process was investigated.The results show that 98.4%Ni and 98.5%Cu can be synchronously extracted when the ore particle size is 75-80μm,the roasting time is 2 h,the mass ratio of NH;Cl to ore is 1.6:1 and the roasting temperature is 550°C.The evolution behavior of various minerals was elucidated using X-ray diffraction(XRD)coupled with scanning electron microscopy(SEM).The kinetics of the chlorination process based on the differential thermal and thermogravimetric analysis(DTA-TG)data was analyzed by Kissinger method and Flynn-Wall-Ozawa(FWO)method.The chlorination process of low-grade nickel-copper sulfide ore mainly contains two stages:the decomposition of NH;Cl and the chlorination of ore.The maximum apparent activation energies(Ea)at two stages are determined to be 114.8 and 144.6 kJ/mol,respectively.The condensed product of exhaust gas is determined to be ammonium chloride,which can be recycled as the reactant again,making the process economic and clean.展开更多
This paper presents the analysis and implementation of a synchronizer to the grid using a linear Kalman filter. The synchronizer is used in a single-phase inverter, which is applied in an environment of microgrids. Th...This paper presents the analysis and implementation of a synchronizer to the grid using a linear Kalman filter. The synchronizer is used in a single-phase inverter, which is applied in an environment of microgrids. The inverter converts the energy that comes from renewable energy sources （photovoltaic, wind, fuel cell, etc.）. The main objective of obtaining the phase of the grid is to achieve a power factor close to unity in the inverter. For this reason it is vital that the phase difference between the synchronizer and the grid zero. To obtain synchronizer algorithm using LKF （linear Kalman filter） is necessary to know the EKF （extended Kalman filter）. This allows to analyze the operation of the filter, which allows to reach reduce linear Kalman filter or also known as simplified Kalman filter. It is necessary to generate an orthogonal signal in order to obtain a stationary reference frame from a single-phase grid because the linear Kalman filter works with a stationary reference frame. Orthogonal signal is created with an all-pass filter.展开更多
基金the National Natural Science Foundation of China(No.52074069)the Natural Science Foundation of Hebei Province(No.E2020501022)+1 种基金the National Basic Research Program of China(No.2014CB643405)the Fundamental Research Funds for the Central Universities,China(No.N2223027)。
文摘To efficiently co-extract Ni and Cu from low-grade nickel-copper sulfide ore,chlorination roasting with NH;Cl followed by a water leaching process was investigated.The results show that 98.4%Ni and 98.5%Cu can be synchronously extracted when the ore particle size is 75-80μm,the roasting time is 2 h,the mass ratio of NH;Cl to ore is 1.6:1 and the roasting temperature is 550°C.The evolution behavior of various minerals was elucidated using X-ray diffraction(XRD)coupled with scanning electron microscopy(SEM).The kinetics of the chlorination process based on the differential thermal and thermogravimetric analysis(DTA-TG)data was analyzed by Kissinger method and Flynn-Wall-Ozawa(FWO)method.The chlorination process of low-grade nickel-copper sulfide ore mainly contains two stages:the decomposition of NH;Cl and the chlorination of ore.The maximum apparent activation energies(Ea)at two stages are determined to be 114.8 and 144.6 kJ/mol,respectively.The condensed product of exhaust gas is determined to be ammonium chloride,which can be recycled as the reactant again,making the process economic and clean.
文摘This paper presents the analysis and implementation of a synchronizer to the grid using a linear Kalman filter. The synchronizer is used in a single-phase inverter, which is applied in an environment of microgrids. The inverter converts the energy that comes from renewable energy sources （photovoltaic, wind, fuel cell, etc.）. The main objective of obtaining the phase of the grid is to achieve a power factor close to unity in the inverter. For this reason it is vital that the phase difference between the synchronizer and the grid zero. To obtain synchronizer algorithm using LKF （linear Kalman filter） is necessary to know the EKF （extended Kalman filter）. This allows to analyze the operation of the filter, which allows to reach reduce linear Kalman filter or also known as simplified Kalman filter. It is necessary to generate an orthogonal signal in order to obtain a stationary reference frame from a single-phase grid because the linear Kalman filter works with a stationary reference frame. Orthogonal signal is created with an all-pass filter.
