Description of Plant : The Olushandja water treatment plant consists of two processes for purifying water, a batch plant and a slow sand filter plant
The process of the batch plant producing 1 600 m3/day is as follows: Raw-water is filled into four basins. While filling, the flocculant and lime are added manually to the basins. The flocculant then binds with the silt in the water. After mixing, the particles are allowed to settle to the bottom of the basin over 3-4 hours, before the clearer water on top is pumped out to the reservoir. Here chlorine is dosed for disinfection, before the water is distributed to the customers.
The other treatment process consists of filters only. The raw-water is abstracted from the canal and stored in a tank. After the tank, a flocculant is added to the water before it enters the roughing filters, where a portion of the suspended particles is removed. The roughing filters contain fairly coarse sand.
From the roughing filters, the water flows to the slow sand filters, which contain much finer sand than the previous step. These remove the rest of the silt particles in the water.
Thereafter the water collects into a 400 m3 clear water sump, where chlorine is dosed for disinfection. This process produces another 740 m3/day.
