When this process is used to treat water, there is need to create an environment for the bacteria that mimics the soil conditions in which this process occurs naturally. Generally, also, the chemical energy needs to be added artificially to the system to stimulate the denitrification process. Thus, a denitrification plant, in its most basic form, comprises an injection well for adding nutrients, a biological reactor, and a pumping well for the abstraction of treated water. This technology has been used in projects in South Africa. Operations and Maintenance Denitrification technologies have high energy requirements associated with the suspended growth reactors.
Electrical energy is required in order to keep the bacterial floc in suspension by stirring.
Chemical energy sources are also required in many systems. With underground biological denitrification, problems may arise as aquifer pore spaces clog with biological matter. In such cases, the recommended approach is to undertake denitrification in an above-ground biological reactor with underground recirculation of the treated water as a secondary treatment. C Figure 37. This technology requires specialised skills and knowledge to operate effectively.