The influence of the recycle ratio on the removal of coking wastewater has been researched using the anaerobicanoxic-aerobic (A/A/O) biofilm process. The research indicates that the concentrations of chemical oxygen...The influence of the recycle ratio on the removal of coking wastewater has been researched using the anaerobicanoxic-aerobic (A/A/O) biofilm process. The research indicates that the concentrations of chemical oxygen demand (COD) and NO3 -N in the water are the lowest when the recycle ratio is 3:1 ,but the removal efficiency of total cyanide (TCN) is the highest when the recycle ratio is 1: 1. The removal efficiency of NH4^+ -N is more than 99% at all three different recycle ratios. Compared with Grade A of the National Discharge Standard (GB 8978--1996), the effluent NH4 -N is standard,but COD and TCN can not meet the requirements and further treatment processes are needed.展开更多
The limestone-gypsum flue gas desulfurization (FGD) process has become the most widespread process in the world for sulfur removal. The swirl-jet-absorbing wet limestone-gypsum sintering FGD technology was developed...The limestone-gypsum flue gas desulfurization (FGD) process has become the most widespread process in the world for sulfur removal. The swirl-jet-absorbing wet limestone-gypsum sintering FGD technology was developed for sintering flue gas desulfurization,and this process produces volumes of wastewater with various contaminants that requires treatment before disposal or reuse. In this study, the wastewater quality from three different sintering FGD systems at Baosteel Group was investigated and compared with wastewater from power plant FGD. A treatment process was proposed which is suitable for sintering FGD wastewater. After treatment with a neutralization, coagulation and sedimentation process, heavy metals in the sintering FGD wastewater were reduced to a level meeting the relevant emission standards ,but the pH and ammonia concentration were too high, and a further treatment process was needed. Due to certain similarities and complementarities between sintering FGD wastewater and coking wastewater, it is entirely feasible to mix the pretreated sintering FGD wastewater into a biological coking wastewater treatment system. This study indicates that it is entirely feasible to mix pretreated sintering FGD wastewater into the biological treatment systems used for coking wastewater from the iron and steel industries.展开更多
Integrating solar power utilization systems with coal-fired power units, the solar aided coal-fired power generation (SACPG) shows a significant prospect for the large-scale utilization of solar energy and energy savi...Integrating solar power utilization systems with coal-fired power units, the solar aided coal-fired power generation (SACPG) shows a significant prospect for the large-scale utilization of solar energy and energy saving of thermal power units. The methods and mechanism of system integration were studied. The parabolic trough solar collectors were used to collect solar energy and the integration scheme of SACPG system was determined considering the matching of working fluid flows and energy flows. The thermodynamic characteristics of solar thermal power generation and their effects on the performance of thermal power units were studied, and based on this the integration and optimization model of system structure and parameters were built up. The integration rules and coupling mecha- nism of SACPG systems were summarized in accordance with simulation results. The economic analysis of this SACPG system showed that the solar LEC of a typical SACPG system, considering CO2 avoidance, is 0.098 $/kW·h, lower than that of SEGS, 0.14 $/kW·h.展开更多
文摘The influence of the recycle ratio on the removal of coking wastewater has been researched using the anaerobicanoxic-aerobic (A/A/O) biofilm process. The research indicates that the concentrations of chemical oxygen demand (COD) and NO3 -N in the water are the lowest when the recycle ratio is 3:1 ,but the removal efficiency of total cyanide (TCN) is the highest when the recycle ratio is 1: 1. The removal efficiency of NH4^+ -N is more than 99% at all three different recycle ratios. Compared with Grade A of the National Discharge Standard (GB 8978--1996), the effluent NH4 -N is standard,but COD and TCN can not meet the requirements and further treatment processes are needed.
文摘The limestone-gypsum flue gas desulfurization (FGD) process has become the most widespread process in the world for sulfur removal. The swirl-jet-absorbing wet limestone-gypsum sintering FGD technology was developed for sintering flue gas desulfurization,and this process produces volumes of wastewater with various contaminants that requires treatment before disposal or reuse. In this study, the wastewater quality from three different sintering FGD systems at Baosteel Group was investigated and compared with wastewater from power plant FGD. A treatment process was proposed which is suitable for sintering FGD wastewater. After treatment with a neutralization, coagulation and sedimentation process, heavy metals in the sintering FGD wastewater were reduced to a level meeting the relevant emission standards ,but the pH and ammonia concentration were too high, and a further treatment process was needed. Due to certain similarities and complementarities between sintering FGD wastewater and coking wastewater, it is entirely feasible to mix the pretreated sintering FGD wastewater into a biological coking wastewater treatment system. This study indicates that it is entirely feasible to mix pretreated sintering FGD wastewater into the biological treatment systems used for coking wastewater from the iron and steel industries.
基金Supported by the National Natural Science Foundation of China (Grant Nos. 50776028 and 50606010) the Program for New Century Excellent Talents in University (Grant No. NCET-05-0217)
文摘Integrating solar power utilization systems with coal-fired power units, the solar aided coal-fired power generation (SACPG) shows a significant prospect for the large-scale utilization of solar energy and energy saving of thermal power units. The methods and mechanism of system integration were studied. The parabolic trough solar collectors were used to collect solar energy and the integration scheme of SACPG system was determined considering the matching of working fluid flows and energy flows. The thermodynamic characteristics of solar thermal power generation and their effects on the performance of thermal power units were studied, and based on this the integration and optimization model of system structure and parameters were built up. The integration rules and coupling mecha- nism of SACPG systems were summarized in accordance with simulation results. The economic analysis of this SACPG system showed that the solar LEC of a typical SACPG system, considering CO2 avoidance, is 0.098 $/kW·h, lower than that of SEGS, 0.14 $/kW·h.