城区感潮河道底泥污染特征调查研究

Investigation and Analysis on the Polluting Characteristics of Typical Tidal Urban River Sediments

为掌握河道污染特征及其目标污染物,在深圳某感潮河道自上游到下游选取了6个点位采集底泥和上覆水体样本进行分析。结果表明,与内陆非感潮河道主要受有机污染不同,该河道底泥遭受硫化物(AVS)污染严重,硫化物(AVS)含量为2 341～3 202 mg-S/kg干重,TOC含量为2. 95%～3. 79%。底泥中PAHs含量范围为699～1 029μg/kg干重,TPHs含量范围为1 084～1 341 mg/kg干重;而PCBS含量则低于检测限50μg/kg干重。确定该感潮河道污染底泥首要控制目标污染物是硫化物(AVS)和有机物。由于河道日均受涨、落潮两次潮汐影响,河道底泥淤积处于相对平衡状态,为保证河道泄洪和通航需要,建议对河道底泥的特征污染物采取原位处理方式,以降低成本,避免二次污染。

Focusing on the polluting characteristics of typical tidal urban river, this research investigates the characteristic of sediment pollution based on the case of a tidal river in Shenzhen. The result shows it is the serious problem of sulfide and organic pollution in urban river sediment, where the amount of acidic volatile sulfide （AVS） is 2 341 -3 202 mg-S/kg dry sediment and total organic carbon （TOC） is 2.95% -3.79%. The amount of PAHs is 699 - 1 029μg/kg dey sediment and TPHs is 1 084 - 1 341 mg/kg dey sediment, while the amount of PCBS is below the detection limit of 50μg/kg dry sediment. The primary pollution of this tidal urban river is acidic volatile sulfide （AVS） and total organic carbon （TOC）. Considering the balance storage of the sediment because of the tidal river, the advice about the polluted sediments is in-situ treatment based on the target sediment pollutants in order to reduce the treatment cost and avoid the second polluted.