Abstract:

The fine particles suspended in industrial wastewater are not only the main pollutants themselves, but also easily provide attachment sites for other forms of pollutants. For the removal of fine particles in industrial wastewater treatment, deep filtration based on microchannel separation meets the requirements of separation accuracy and has a high upper limit of pollutant accommodation. It has obvious advantages of high efficiency and stability, long operation cycle and low cost. However, the operating performance of the deep filtration process is often affected by many factors. Unreasonable bed structure design is likely to cause deterioration of effluent quality and high operating energy consumption. In this paper, a multi-layer structure bed was designed by using non-single medium, and the combination of micro-channels in each layer was used to form a micro-channel different from any single medium. At the same time, relevant equipment was built and batch tests were carried out. The results showed that the proposed multi-medium stratified bed control improvement scheme reduced the total bed height to 2/3 of the original height, the separation effect was not significantly reduced, and the total pressure drop was reduced to 33% before the improvement. Compared with the single medium bed, the filtration energy consumption was reduced by 25%, the bed at all levels was closer to the upper limit state, and the useless work loss in the backwashing process was reduced. The control method could significantly reduce the energy consumption of the equipment during the whole operation cycle. Therefore, the improvement scheme of using multi-medium to design layered bed to regulate the microchannel structure in the bed was helpful to improve the operation performance of deep filtration equipment and make it more economical and lightweight.

Key words: deep filtration, operation performance, control method, experimental validation, pressure drop

摘要：

工业废水中悬浮的细微颗粒不仅本身是主要的污染物，并且极易为其他形式存在的污染物提供附着位置。对于工业废水处理中细微颗粒的去除问题，基于微通道分离的深层过滤满足分离精度要求的同时对污染物的容纳上限高，具有高效稳定、运行周期长、成本投入低的明显优势。然而深层过滤过程的运行性能往往受多方面因素的影响，不合理的床层结构设计容易造成出水水质恶化及运行能耗过高。本文利用非单一介质设计多层结构的床层，利用各层微通道之间的组合形成区别于任意单一介质的微通道形式，同时搭建相关设备并开展批量实验。结果表明，所提多介质分层床层调控的改进方案将总床层高度降为原高度的2/3，分离效果没有显著降低，同时总压降降低为改进前的33%。相对于单一介质的床层降低25%的过滤能耗，各级床层更接近上限状态，减少反洗过程无用功损失，调控方法可以显著降低完整运行周期内的设备能耗。因此，利用多介质设计分层床层以调控床层内微通道结构的改进方案有助于提升深层过滤设备运行性能，使其更具有经济性和轻量性。

关键词: 深层过滤, 运行性能, 调控方法, 实验验证, 压降