Your drinking water can be full of various mineral contaminants. These include calcium, magnesium, and silica.

You may be wondering if this drinking water is harmful to my health. And, what can be done to remove this impurity from the drinking water?

Well, wonder no more!

We have below a detailed explanation about the effects of silica in drinking water as well as methods to remove it. Furthermore, we’ve added the most commonly faced problems in the silica removal process.

Let’s jump right in!

Table of Contents

What is Silica?

Silica is most commonly found on Earth in the form of quartz. It is also a significant component of sand. In fact, after oxygen, silicon is the second most abundant element present on our planet. The chemical composition of silica is SiO2.

Silica is a contaminant that is usually found in groundwater or well water. It is also commonly transferred via food. Generally, silica combines with other mineral contaminants found in water, such as calcium or magnesium. Such colloidal silica forms a gelatinous material that is made from non-diffusible particles. These materials make silica challenging to filter.

What Are Some of the Effects of Silica?

Silica is one of the essential minerals for our bodies. According to a study conducted by the International Journal of Endocrinology, silica is found to be essential for increasing bone strength and mineral density. Similarly, it is a crucial element in aiding the formation of collagen. Collagen keeps our skin and hair elastic and also helps in repairing it quickly.

However, these effects depend on the dosage. The safety limit is reported to be about 700 to 1750 mg per day. Silica generally does not have many side effects for healthy individuals.

Some side-effects of consuming high amounts of silica can be allergic reactions, upset stomach, and aggravated hypoglycemia. It can also cause a scale-build up in your plumbing system. This further leads to foul smells and stains that are difficult to remove.

How to Remove Silica from Water?

The most effective filtration technique for silica is reverse osmosis. However, you are likely to receive better results if you use it in conjunction with a water softener. This is due to two reasons.

One: silica, as an impurity, has many forms. It combines easily with other impurities, so it becomes difficult to target. Two: Since it is a mineral impurity, a softening system is likely to be more effective at removing it once it has been filtered. A reverse osmosis system is capable of removing up to 90% of the silica. Adding a secondary system will, therefore, take care of the rest.

The different forms of silica will need to be targeted separately. For instance, granular silicates can be removed via sedimentation and filtration. Chemical precipitation method can be used for dissolved and colloid silicates. Reverse osmosis is also meant to target dissolved silicates.

One of the most common methods of removing silica from drinking water is lime softening. This method is based on the reaction of calcium hydroxide (lime) with the silica colloids. This reaction works on hardness causing minerals such as calcium and magnesium, creating flakes of these minerals. These flakes then absorb silica. Once all the silica is absorbed, the water can be put through a filter to obtain silica-free water.

Problems in Removing Silica from Water

As we mentioned before, silica is tough to remove. It should be noted that silica is a primary ingredient in glass. These are the properties that allow it to cut holes into the semi-permeable membrane. This makes the membrane ineffective against not just silica but also other impurities.

The main problem is that no one system is capable of removing silica completely. Water needs to be pre-filtered to remove the bigger impurities that may damage the membranes. Similarly, during ion-exchange, the resin exchangers need to be continuously recharged or replaced entirely. The maintenance costs are, thus, reasonably high for this process.

The problem with the lime softening method is that it can be quite costly. Furthermore, there are a lot of residuals produced, which will be a hassle to discard. All these problems make the silica removal from your drinking water a tough process.

In Summary,

Silica is one of the most common elements found on Earth. The good thing is that it does not have too many negative consequences for a healthy individual. However, if you are prone to allergies, diabetes, or have other health conditions, then you should look into installing these mechanisms to get silica-free water.

(Last Updated on June 15, 2020 by Sadrish Dabadi)

Nina Howell is a Rewenable Energy researcher and consultant based out of Houston, Texas Area. She earned her Master's Degree in Energy and Earth Resources from Austin Jackson School of Geosciences in 2010, and a Bachelor's Degree in Environmental Science from State University of New York College of Environmental Science and Forestry in 2008. Nina has been working in the energy sector since 2011. She worked as an Energy Supply Analyst from 2011 to 2017 in Bounce Energy and then as a Research and Energy Consultant at GE Renewable Energy from March 2017 to February 2020 . Nina is a mom of 2 beautiful children who are joy to her life. She strongly believes in eco-friendly living and is vocal about renewable energy, environmental issues, water crisis, and sustainable living.