Drying operations are of grave importance to realize the reduction and utilization of sewage sludge resources,but the conventional thermal evaporation drying(TED)technology presents challenges due to the need for a la...Drying operations are of grave importance to realize the reduction and utilization of sewage sludge resources,but the conventional thermal evaporation drying(TED)technology presents challenges due to the need for a large amount of thermal energy to conquer the phase-change latent heat of moisture.Herein,we report a non-phase change technology based on particle high-speed self-rotation in a cyclone for fast,low-temperature drying of viscous sludge with high-moisture contents.Dispersed phase medium(DPM)is introduced into the cyclone self-rotation drying(CSRD)reactor to enhance the dispersion of the viscous sludge.The effects of carrier gas temperature,feeding rate,size,and proportion of DPM particles in the drying process are systematically examined.Under optimal operating conditions,the weighted content of moisture in the viscous sludge could be reduced from 80%to 15.01%in less than 5 s,achieving a high drying efficiency of 95.79%.Theoretical calculations also reveal that 89.26%of the moisture is removed through non-phase change pathway,contributing to a 522-fold increase in the drying rate of CSRD compared to TED technology.This investigation presents a sustainable effective approach for high moisture viscous sludge treatment with low energy consumption and carbon emissions.展开更多
随着双有源桥开关频率的不断提高,开关损耗在总损耗中的占比逐渐增大。零电压开关(zero voltage switching,ZVS)控制策略已成为降低开关损耗的主要手段。然而,传统ZVS控制策略在考虑死区时间时,存在ZVS区域不连续和移相比突变的问题,影...随着双有源桥开关频率的不断提高,开关损耗在总损耗中的占比逐渐增大。零电压开关(zero voltage switching,ZVS)控制策略已成为降低开关损耗的主要手段。然而,传统ZVS控制策略在考虑死区时间时,存在ZVS区域不连续和移相比突变的问题,影响系统稳定。为了解决该问题,提出一种在全功率范围内移相比非突变的ZVS和电流应力优化策略。在中等功率范围内,由于死区时间的影响,所有开关器件的ZVS无法完全实现,以牺牲第1个桥臂开关器件的ZVS为代价,确保移相比的连续变化。在高功率范围内,以移相比连续变化为目标,重新调整分界线,实现中等功率范围与高功率范围的无缝切换。理论分析表明,提出的优化策略能够在全功率范围内保证移相比的连续性。通过搭建小功率实验平台,实验结果验证了所提优化策略的正确性和有效性。展开更多
基金supported by the National Key Research and Development Program of China(2019YFA0705800)the National Natural Science Foundation of China(52030001)the Science&Technology Commission of Shanghai Municipality(20dz1207600).
文摘Drying operations are of grave importance to realize the reduction and utilization of sewage sludge resources,but the conventional thermal evaporation drying(TED)technology presents challenges due to the need for a large amount of thermal energy to conquer the phase-change latent heat of moisture.Herein,we report a non-phase change technology based on particle high-speed self-rotation in a cyclone for fast,low-temperature drying of viscous sludge with high-moisture contents.Dispersed phase medium(DPM)is introduced into the cyclone self-rotation drying(CSRD)reactor to enhance the dispersion of the viscous sludge.The effects of carrier gas temperature,feeding rate,size,and proportion of DPM particles in the drying process are systematically examined.Under optimal operating conditions,the weighted content of moisture in the viscous sludge could be reduced from 80%to 15.01%in less than 5 s,achieving a high drying efficiency of 95.79%.Theoretical calculations also reveal that 89.26%of the moisture is removed through non-phase change pathway,contributing to a 522-fold increase in the drying rate of CSRD compared to TED technology.This investigation presents a sustainable effective approach for high moisture viscous sludge treatment with low energy consumption and carbon emissions.
文摘随着双有源桥开关频率的不断提高,开关损耗在总损耗中的占比逐渐增大。零电压开关(zero voltage switching,ZVS)控制策略已成为降低开关损耗的主要手段。然而,传统ZVS控制策略在考虑死区时间时,存在ZVS区域不连续和移相比突变的问题,影响系统稳定。为了解决该问题,提出一种在全功率范围内移相比非突变的ZVS和电流应力优化策略。在中等功率范围内,由于死区时间的影响,所有开关器件的ZVS无法完全实现,以牺牲第1个桥臂开关器件的ZVS为代价,确保移相比的连续变化。在高功率范围内,以移相比连续变化为目标,重新调整分界线,实现中等功率范围与高功率范围的无缝切换。理论分析表明,提出的优化策略能够在全功率范围内保证移相比的连续性。通过搭建小功率实验平台,实验结果验证了所提优化策略的正确性和有效性。
