Silica, also known as silicon dioxide (SiO2) or mineral quartz, is a derivative compound of the chemical element silicon (Si). This very common mineral has many different forms and is most easily recognized in nature as the mineral quartz and the second most abundant element in the Earth’s crust, after oxygen.

Though the solubility of silica in water is low and slow, its sheer abundance means that is present in ground water supplies. Silica exist in water in two main forms one “Reactive Silica”. which is dissolved in water as the bisilicate ion making it weak acid and the other form is known as “Colloidal Silica” a polymeric form of silica where the particles are ultra-fine.

Most water contains an abundance of silicon and its derivatives, silica (SiO2) or silicates (SiO4 – and SiO32–). Silica concentration in water is commonly less than 30 mg/L, although concentrations higher than 100 mg/L are not unusual. Silica in Water can Cause Significant Problems for Industrial Water Treatment.

Silica can cause a number of problems for industrial water treatment:

• Scaling: When silica is present in water, it can cause scaling on heat exchangers, boilers, and other process equipment. Scaling is the build-up of mineral deposits on the surfaces of process equipment.
• Corrosion: Silica can also cause corrosion in process equipment.
• Fouling: Silica can foul membranes and other process equipment, which can lead to a decrease in efficiency and an increase in operating costs.
• If you are using water in your industrial process, it is important to test for the presence of silica and to take steps to remove it if it is present. There are a number of ways to remove silica from water, including reverse osmosis, ion exchange, and nanofiltration.

Advance Engineers are experts in analysers and water treatment. They offer a wide range of products and services to help you reduce silica in your water.

Lime-soda softening is one way to reduce silica in your water. This process uses CaOH and Soda Ash to raise the pH to extreme levels, causing precipitation of CaCO3 and MgOH. Silica binds to the MgOH and settles out.

Ultra-filtration is another way to reduce silica in your water. Specialised polymeric ultra-filters are used for industrial water treatment to capture colloidal silica.

Anion exchange can also be used for reactive silica. This ion-exchange method can be used for reactive silica.

Whole-House Reverse Osmosis is another way to reduce all types of silica. For residential settings, whole house RO is one way to reduce all types of silica.

Because it is so difficult to remove silica from the water, the most common approach to deal with it is one of prevention and mitigation of deposits. Some tips to prevent and mitigate silica deposits include:

• Lowering water temperature below 140 F in dishwashers
• Using soft-water detergents with no phosphorus and air-drying only in dishwashers
• Washing delicate glassware by hand only
• Keeping water off of chrome surfaces and glass shower doors to prevent silica spotting
• Cleaning deposits at water line

If you have any questions about how to reduce silica in your water, or if you need any assistance, please don’t hesitate to contact Advance Engineers. We’re here to help!