In micro-filtration, contaminated water is pressed through a synthetic membrane made of organic polymers. This advanced (semi-permeable) membrane typically features a pore size of 0.01-12µm. Mostly built in cylindrical modules to reduce required surface area. Also applied in small-scale water treatment systems (Perfector-E).
Both construction and operation costs are high. Main cost includes membrane expenses and energy costs for pressurizing.
Can be applied at local or centralized level, but might be too expensive for use at local level. Labor requirements are not much but need education and careful attention, therefore experienced operator is required. This person can operate other processes at same time.
The energy requirements give microfiltration a high ecological footprint. Colloidal and suspended material, bacteria and not too small viruses are retained. Produced sludge is highly contaminated, requiring safe handling and disposal to avoid risk to public health and contamination of groundwater.
High-tech option operated at pressure of 0.7-3.4 bar. Local construction in developing countries unlikely. For operation: rejected compounds need to be removed regularly. Different cleaning options exist in the form of reversed flow, air flushing or chemical cleaning.
Produces good quality water with high level of reliability if well maintained. Eventual defects are difficult to mend. Water supply might be out of use for long periods, negatively influencing the users’ willingness to pay for the centralized water supply.
No relevant remarks for Micro filtration.