Silvafloc, organic polyelectrolyte for the flocculation process

Flocculation is a physical chemical process leading to the formation of a colloidal system in which the solid phase tends to separate forming flakes in suspension. The pH, temperature and ionic strength are environmental factors that strongly influence the flocculation, but it is also simply the formation of aggregates or flakes in suspension by precipitation of dehydrated materials.

Silvafloc is a chemically modified organic product developed by Silvateam that activates amine groups along the polymerised molecular chain, which provides very high reactivity and a broad action range. Silvafloc is in fact a positively charged polyelectrolyte with high flocculating performance.

Organic polyelectrolytes are commercially used as coagulant aids during the flocculation process. Silvafloc acts as a coagulant agent alone and in most circumstances, competes favourably with inorganic electrolytes such as alum, aluminium sulphate, ferric chloride and other flocculants. Due to its chemical structure, Silvafloc can act as an anionic polyelectrolyte for pH values above 8.5, as a cationic polyelectrolyte in acid pH and as a non-ionic polymer as a pH lower than 8.5.

It can be used alone as a primary flocculant in most applications, which simplifies water treatment operations. This happens because it interacts with the solids in suspension, neutralising the positive and negative charges, as an amphoteric particle or with an ionic hydrogen bond. It can be used together with other coagulants such as aluminium sulphate increasing the yield and reducing the treatment cost.

In special applications it is recommended to combine Silvafloc with other coagulants, including aluminium sulphate, resulting in lower costs and increased efficiency, compared with the use of a single flocculant.

Silvafloc is mainly used for sewage treatment. In fact, because of its high molecular weight, it has a greater flocculating power due to the formation of larger flakes thus resulting in a higher sedimentation rate.