New construction of an aerobic wastewater treatment plant for a softdrink bottler in Senegal

A new bottling factory in the Senegalese Bandia region required the construction of a wastewater treatment plant to allow saft discharge of wastewater according to local environmental standards.

Conceptual Formulation

In 2022, the construction work for a new beverage bottling plant for soft drinks in western Senegal started. As a specialist for this type of wastewater, CUSS GmbH was requested to design, install and commission a suitable sewage treatment plant. Since no wastewater analysis values were available prior to planning for this greenfield project, CUSS GmbH was able to draw on its good experience from similar treatment plants in West Africa in order to guarantee safe operation of the system.

In a first mechanical process step, coarse materials and sedimentable materials (e.g. sand) were removed through a sand trap and a curved screen. An aerated mixing and equalizing tank is installed to compensate the daily fluctuations in temperature, pH and flow rate. The increased organic load as well as nitrogen and phosphorus are removed in several batches in an aerobically operating sequencing batch reactor (SBR). The clear water discharge reaches the required limit values to be able to be drained into a water body. The excess sludge which forms in the reactor over time is temporarily stored in an aerated sludge tank before it is conditioned with milk of lime and dewatered in a chamber filter press. The dewatering contributes to an overall volume reduction and ensures lower disposal costs for the customer.

Already during the planning phase, possible production expansions were discussed in close cooperation with the customer. In this context, another area was determined in advance on the sewage treatment plant, in which another activated sludge tank can be easily installed in the future to treat additional amounts of wastewater.