This study investigated the influence of precipitators and wet flue gas desulfurization equipment on characteristics of PM_(2.5)emission from coal-fired power stations.We measured size distribution and removal efficie...This study investigated the influence of precipitators and wet flue gas desulfurization equipment on characteristics of PM_(2.5)emission from coal-fired power stations.We measured size distribution and removal efficiencies,including hybrid electrostatic precipitator/bag filters(ESP/BAGs)which have rarely been studied.A bimodal distribution of particle concentrations was observed at the inlet of each precipitator.After the precipitators,particle concentrations were significantly reduced.Although a bimodal distribution was still observed,all peak positions shifted to the smaller end.The removal efficiencies of hybrid ESP/BAGs reached 99%for PM_(2.5),which is considerably higher than those for other types of precipitators.In particular,the influence of hybrid ESP/BAG operating conditions on the performance of dust removal was explored.The efficiency of hybrid ESP/BAGs decreased by 1.9%when the first electrostatic field was shut down.The concentrations and distributions of particulate matter were also measured in three coal-fired power plants before and after desulfurization devices.The results showed diverse removal efficiencies for different desulfurization towers.The reason for the difference requires further research.We estimated the influence of removal technology for particulate matter on total emissions in China.Substituting ESPs with hybrid ESP/BAGs could reduce the total emissions to 104.3 thousand tons,with 47.48 thousand tons of PM_(2.5).展开更多
5G technology can greatly improve spectral efficiency(SE)and throughput of wireless communications.In this regard,multiple inputmultiple output(MIMO)technology has become the most influential technology using huge ant...5G technology can greatly improve spectral efficiency(SE)and throughput of wireless communications.In this regard,multiple inputmultiple output(MIMO)technology has become the most influential technology using huge antennas and user equipment(UE).However,the use of MIMO in 5G wireless technology will increase circuit power consumption and reduce energy efficiency(EE).In this regard,this article proposes an optimal solution for weighing SE and throughput tradeoff with energy efficiency.The research work is based on theWyner model of uplink(UL)and downlink(DL)transmission under the multi-cell model scenario.The SE-EE trade-off is carried out by optimizing the choice of antenna and UEs,while the approximation method based on the logarithmic function is used for optimization.In this paper,we analyzed the combination of UL and DL power consumption models and precoding schemes for all actual circuit power consumption models to optimize the trade-off between EE and throughput.The simulation results show that the SE-EE trade-off has been significantly improved by developing UL and DL transmission models with the approximation method based on logarithmic functions.It is also recognized that the throughput-EE trade-off can be improved by knowing the total actual power consumed by the entire network.展开更多
In order to build a power plant with high efficiency,low investment and zero warm water discharge,a series of innovations are applied to the two 1 000-MW units of Ninghai Power Plant.The new technologies include the c...In order to build a power plant with high efficiency,low investment and zero warm water discharge,a series of innovations are applied to the two 1 000-MW units of Ninghai Power Plant.The new technologies include the closed-circuit system for seawater cooling tower with a spraying area of 13 000 m2,the main buildings with reinforced concrete structure,the plasma ignition system for tower boiler and the fieldbus control system.Optimization measures are taken in some aspects,such as the open point of the turbine overload valves,the boiler dimensions,the technical process,the electric system,the building structures and the layout of the power plant.The units have been running for more than half a year with the thermal efficiency as high as 45.79% and without warm water discharged,which indicates that all the systems are safe and steady and the original purpose of optimization has been realized.展开更多
基金Supported by the National Basic Research Pro-gram of China(973 Program)(2013CB228506).
文摘This study investigated the influence of precipitators and wet flue gas desulfurization equipment on characteristics of PM_(2.5)emission from coal-fired power stations.We measured size distribution and removal efficiencies,including hybrid electrostatic precipitator/bag filters(ESP/BAGs)which have rarely been studied.A bimodal distribution of particle concentrations was observed at the inlet of each precipitator.After the precipitators,particle concentrations were significantly reduced.Although a bimodal distribution was still observed,all peak positions shifted to the smaller end.The removal efficiencies of hybrid ESP/BAGs reached 99%for PM_(2.5),which is considerably higher than those for other types of precipitators.In particular,the influence of hybrid ESP/BAG operating conditions on the performance of dust removal was explored.The efficiency of hybrid ESP/BAGs decreased by 1.9%when the first electrostatic field was shut down.The concentrations and distributions of particulate matter were also measured in three coal-fired power plants before and after desulfurization devices.The results showed diverse removal efficiencies for different desulfurization towers.The reason for the difference requires further research.We estimated the influence of removal technology for particulate matter on total emissions in China.Substituting ESPs with hybrid ESP/BAGs could reduce the total emissions to 104.3 thousand tons,with 47.48 thousand tons of PM_(2.5).
文摘5G technology can greatly improve spectral efficiency(SE)and throughput of wireless communications.In this regard,multiple inputmultiple output(MIMO)technology has become the most influential technology using huge antennas and user equipment(UE).However,the use of MIMO in 5G wireless technology will increase circuit power consumption and reduce energy efficiency(EE).In this regard,this article proposes an optimal solution for weighing SE and throughput tradeoff with energy efficiency.The research work is based on theWyner model of uplink(UL)and downlink(DL)transmission under the multi-cell model scenario.The SE-EE trade-off is carried out by optimizing the choice of antenna and UEs,while the approximation method based on the logarithmic function is used for optimization.In this paper,we analyzed the combination of UL and DL power consumption models and precoding schemes for all actual circuit power consumption models to optimize the trade-off between EE and throughput.The simulation results show that the SE-EE trade-off has been significantly improved by developing UL and DL transmission models with the approximation method based on logarithmic functions.It is also recognized that the throughput-EE trade-off can be improved by knowing the total actual power consumed by the entire network.
文摘In order to build a power plant with high efficiency,low investment and zero warm water discharge,a series of innovations are applied to the two 1 000-MW units of Ninghai Power Plant.The new technologies include the closed-circuit system for seawater cooling tower with a spraying area of 13 000 m2,the main buildings with reinforced concrete structure,the plasma ignition system for tower boiler and the fieldbus control system.Optimization measures are taken in some aspects,such as the open point of the turbine overload valves,the boiler dimensions,the technical process,the electric system,the building structures and the layout of the power plant.The units have been running for more than half a year with the thermal efficiency as high as 45.79% and without warm water discharged,which indicates that all the systems are safe and steady and the original purpose of optimization has been realized.
