基于热成像技术的污水排放源识别研究

污水暗排口是一种较难监测的污染源.为了更好地探索监测这种污染源的方法,本研究以北京市城区积水潭处的护城河为对象,利用热成像技术对模拟污水暗排口进行了探测.结果表明,模拟污水与河道中的原水的温度分布存在显著差异,原水温度分布均匀,而模拟污水排入后水面温度呈辐射状同心圆分布,从红外图像上可以明确地把两种水体区分开来.实验还研究了在异质水体排入时水面红外图像特征随时间的变化情况.结果表明,在有异质水体排入时,图像中会出现温度异常的水域;随着异质水体的持续排入,温度异常水域开始逐渐扩大.研究结果为利用热成像技术遥感监测污水暗排口提供了依据.

Monitoring of underwater sewage outflow using thermal infrared technology

Underwater sewage outflow, a source of water pollution, is very difficult to find and monitor. To establish a practicable methodology to monitor this kind of pollution source, this study focuses on applying thermal infrared technology to identify the underwater sewage outflow. Two experiments were carried out: controlled and simulation experiments. There are significant differences between the surface-temperature-distribution patterns of a clean water body and a polluted water body. The surface temperature of the clean water is uniform with very small differences between the maximum and minimum, while that of the polluted water is distributed like circles with big differences between the maximum and minimum. Thus we concluded that the thermal infrared technology could distinguish polluted and clean water bodies. We also analyzed the temporal variation features of temperature images. The results reveal that when abnormal water is interfused, the surface temperature diffuses gradually from the central point to outside. As the effluent discharge continues, the area of the abnormal temperature gradually increases. These results provide the basis for monitoring of underwater outflow using thermal infrared technology.