Natural Attenuation of Emerging Pharmaceuticals by Bank Filtration in Addressing Regional Groundwater Management Issues - Dimkic et al. page 09


Why Bank Filtration?

The bank filtration method is used to benefit from the efficiency of purification processes in groundwater (Dimkić, 2007). Namely, self-purification processes during groundwater flow lead to the elimination or attenuation of diverse undesirable substances found in river water, on its way to the water well.
An aquifer is a hydrological medium, created as a result of a specific geological genesis. Several natural factors govern purification processes within the aquifer, such as the extent of the aquifer,

groundwater flow parameters, the size and nature of porosity, grain-size distribution, mineral composition, the natural electrochemical balance between water and rock, and physical, chemical and biochemical characteristics.

The processes which take place in an aquifer are numerous and diverse. In addition to convective transport of solutes, groups of processes include: dispersion processes, exchange processes between the solid and the liquid phase, and degradation processes (resulting in the “disappearance” of solutes from the liquid and solid phases of the aquifer). The most important of these processes can be presented as shown in Table 2 below.

tabele_02

A general schematic of the production line of a bank-filtration water source is shown in Figure 11.

figure_11