汛期黄河下游悬浮颗粒物粒度分布及其对铜离子的模拟吸附研究

Granularity distribution of the suspended particles and adsorption of Cu^(2+) from the Lower Reaches of the Yellow River during Flood Seasons

为跟踪2004年6月19日至7月13日实施的黄河第三次调水调沙工程,2004年7月21日于东营胜利黄河大桥站位采集水样。对黄河下游悬浮物浓度、粒度分布进行了分析。结果表明,当天本站位悬浮物质量浓度为1.43 g/L,悬浮颗粒物粒度在63μm以下部分累积分布占99.3%。作者模拟汛期黄河下游河水的悬浮物浓度、年平均水温及pH,研究悬浮物对重金属Cu2+的吸附规律,并探讨了悬浮物浓度及盐度对吸附的影响。Cu2+在水体中会由于水解、絮凝、沉淀、络和等损失一部分,在研究吸附时对此部分进行了扣除。水体悬浮颗粒物对重金属Cu2+的吸附等温线吸附符合Langmuir方程。随悬浮物浓度的增加,其对Cu2+的吸附容量增大,吸附量减小。悬浮物浓度、pH一定时,在盐度为0~5时,吸附量随盐度的升高而迅速降低,当盐度在5~25时,吸附量基本不变。

Adsorption of suspended particles is an important process controlling dissolved metal concentrations, bioavailability, and transport of trace metals. Samples used for the experiments were collected from Kenli, located at the lower-reaches of the Yellow River, in July 2004. The flux was 835 ma/s, salinity was 0.65, and the concentration of suspended particles was 1.43 kg/m^3. Granularity of suspended particles below 63 μm accounts for 99.30%. Adsorption isotherm of Cu^2＋ can be characterized by Langmuir equation. Effects of different suspended particles concentrations and salinities on adsorption capacity have been discussed in this article.