In order to provide safe water to the public, water is treated using a number of water treatment methods, some of which include conventional process components while others are a little more high tech!
What Processes Are Generally Involved In Conventional Water Treatment?
Conventional water treatment may be different around the world but they all follow the same fundamental steps. Generally speaking conventional water treatment in South Africa and around the world involve some form of coagulation/flocculation and sedimentation as well as filtration and disinfection.
Did you know that water today contains more pollutants and other particles than ever before? Read about how plastic waste is affecting our oceans here.
Coagulation and Sedimentation Defined
During the coagulation/flocculation process certain chemicals are introduced to the raw feed water. These may include the following:
- aluminium sulphate
- ferric sulphate
- ferric chloride
- ferric polymers
These chemicals act as coagulants because they have a positive charge which neutralises the negative charge of dissolved and suspended particles in the water. The added chemicals cause the particles to bind to one another, and because they are denser, they settle more rapidly.
Similar to coagulation is the process of flocculation, the process by which fine particulates are caused to clump together into a floc. The floc may then float to the top of the liquid (creaming), settle to the bottom of the liquid (sedimentation), or be readily filtered from the liquid.
What is Filtration?
Filtration aims to remove particulate matter by ways of passing through a porous mechanism of some kind with varying degrees of pore sizes. This mechanism usually consists of sand, gravel and charcoal in conventional solids/liquid separation. What is able to be removed from water during the filtration process is dependent on the size of the filters that have been used.
What is the Goal of Conventional Water Treatment?
One of the end goals of conventional water treatment is to take water from a level where it is unsafe and unusable to where it can not only be safely used but safe to drink. At WEC Projects they aim to provide communities with water treatment facilities so that they may actively take part in water treatment efforts. They hope to provide education and the means to make water available in communities where clean water is difficult to come by. Contact WEC Projects for more information.