Waste Water Treatment in Precipitated Silica Production

Precipitated silica

Since many years the tire industry relies on precipitated silica as an important reinforcement agent in the rubber to improve its performance, such as wet-skid resistance, steering controllability and wear resistance. In general, it plays a major role in the safety of a vehicle and its fuel consumption. But precipitated silica are also extensively used as filler material, anti-caking agents and in oral care products.

Precipitated silica are formed in a reaction process where an alkaline silicate solution is mixed with a mineral acid, while carefully controlling the reaction conditions such as pH, temperature, agitation, time and concentrations. The large quantities of formed silica are separated, washed and then dried. Due to formation of agglomerates, especially in higher concentrations, the solids can be easily handled with conventional equipment such as filter presses. However, due to the sub-micron size of the particles there is slippage, resulting in a polluted waste water stream which needs to be treated.

The CONTIBAC® Filter is the ideal equipment for this application. With its excellent filtration efficiency and the highly effective back-flushing scheme, the waste water can be purified in a single process step, replacing a whole set of process equipment.

FUNDABAC® candle filters have proven to be an ideal choice for many industrial waste water streams where high quality and efficient separation is required. Typical applications are found in the chemical, electronics, pharmaceutical and steel industry.