采用环形水槽研究了沉积物中多环芳烃（PAHs）的释放过程，通过测定水相PAHs浓度考察不同流速下沉积物中PAHs释放情况。试验结果表明，沉积物中PAHs释放速率和释放量受水流流速影响很大，总体上移PAHs浓度随水流流速增加呈上升趋势，从开始静水时的5.602 ug/L增加到流速为60 cm/s时的22.158 ug/L；各层移PAHs浓度随流速增加变化趋势有所不同，表层和中层移PAHs浓度随水流流速的增加呈现上升后下降的趋势，当水流流速分别为20 cm/s和25 cm/s时，表层和中层最大浓度分别为1.816 ug/L 和1.902 ug/L；底层呈逐渐上升的趋势。各物质随水流变化表现出的变化趋势略有不同，各层苊烯和蒽浓度随水流作用变化不大，萘、苊、菲、荧蒽、芘和屈随水流变化总体上呈现上升后下降的趋势。研究还发现沉积物再悬浮引起PAHs释放的同时伴随着沉积物对PAHs的吸附过程。%Sediment resuspension and polycyclic aromatic hydrocarbons (PAHs) release process were investigated in the annular flume in this paper. The aqueous concentration of Σ PAHs was increasing from the initial concentration of 5.602 ug/L to 22.158 ug/L with the flow velocity of 60 cm/s. The peak concentration of Σ PAHs was 1.816 ug/L at the aqueous surface and 1.902 ug/L in the middle as the flow velocities were increased to 20 cm/s and 25 cm/s respectively, and there was a going down trend with the flow velocity increasing to 60 cm/s. The aqueous bottom concentration of Σ PAHs was increasing with the increasing flow velocity. Concentrations of naphthalene, acenaphthylene, phenanthrene, floursnthrene, pyrene and chrysene were increasing at the initial phase and decreasing with the following increasing velocity. The aquatic concentration of PAHs was affected by the concentration of suspended solid produced by the water flow, and the PAHs were released from the suspended solid of low concentration and were adsorbed by the suspended solid of high concentration.
展开▼
