Calcium is a mineral and the major component found in natural and treated waters at different levels. Rainwater and oceanic waters are the purest and the most natural but as it streams through the ground, rocks and any high mineral containing material, quantities of calcium and traces of magnesium are picked up. You don’t have to be a graduate of chemistry to be in a position to treat your water.
How to remove calcium in water: Distillation, reverse osmosis, ion-exchange resin, use of calcium hydroxide, chelating agents are the most common methods of removing calcium from the water. Let us look into each of the above methods in detail.
- 1 Is distillation effective in removing calcium from water?
- 2 Why do people boil water for drinking?
- 3 How does reverse osmosis work?
- 4 Does water filter remove calcium?
- 5 Yes. Ion-exchange resin eliminates calcium and other impurities from water.
- 6 Use of calcium hydroxide in water treatment.
- 7 How do Chelating agents remove calcium in water purification?
- 8 Why Chemical treatment is more of a cleaning process than purification.
- 9 Conclusion.
Is distillation effective in removing calcium from water?
Though expensive it is among the most effective method of softening water. When water is heated to evaporation hard water ions such as calcium are left behind as it settles on the evaporating surface. In addition, as the water boils biological contaminants are also killed.
There are two main methods of distillation used in water treatment.
- Solar distillation
- Multistage flash (MSF) distillation.
Why do people boil water for drinking?
I remember when I was 6 years old our school headteacher told us to drink boiled water because boiled water has no germs. Apart from killing germs what else does boiling do?
Boiling water does remove calcium and other impurities making drinking water safe for consumption. It is an example of simple distillation, easy to perform and no special tools required though not effective on a large scale.
How does reverse osmosis work?
This method together with distillation is the most widely used non-chemical process of removing calcium as a contaminant. It is an application of the desalination process where seawater containing salts such as calcium is removed by the use of controlled pressure across a semi-permeable membrane. In this procedure, the membrane is porous to water molecules and as a result, water hardness ions like Ca2+ and Mg2+ remain behind because these ions will not pass through the pores. Reverse osmosis machines although effective require regular cleaning and replacement maintenance. The membrane works the same way as a water filter.
Does water filter remove calcium?
A water filter is an example of reverse osmosis and the simplest and most suitable method used to soften water. Most water filters use activated carbon to absorb and trap chemicals, filter an assortment of impurities, from chlorine to heavy metals and clean your water supply.
Yes. Ion-exchange resin eliminates calcium and other impurities from water.
This is where a water softening container containing very small porous plastic beads is directly attached to a water supply. These ion-exchange devices act by replacing sodium or sometimes potassium ions (Na+ and K+) with calcium and magnesium ions (Ca2+ and Mg2+ ) thus softening the water. In other words, the structure of the resin bead has a permanent attachment of a fixed negative ion which can attract a positively charged ion. Just like how a magnet works, Sodium ion (Na+) which has a positive charge is attached to the negatively charged exchange site such that the sodium ion is mobile but attached to the resin bead.
As water containing calcium ions and magnesium ions (Ca2+ and Mg2 ) which has a stronger positive charge is let into the resin bead, sodium ions (Na2+) are displaced as calcium or magnesium ions attaches to the bead. In simple terms, one salt is “kicked off” by another salt.
Water softener machines are common choices in ion-exchange as it cleans, automates and makes water safe to drink. The only drawback is that it requires installation and expensive to acquire.
Use of calcium hydroxide in water treatment.
Also referred to as lime softening. Hydrated calcium hydroxide, when added to water, increases the pH level and eventually precipitates the calcium and magnesium ions present. Inappropriate handling of calcium hydroxide is hazardous, thus this technique is normally held in reserve for industrial use.
How do Chelating agents remove calcium in water purification?
These are chemical compounds at times referred to as chelators, chelants, or sequestering agents that react with metal ions such as calcium ions (Ca2+) to form a stable, water-soluble complex. They have a ring-like shape at the center forming at least two bands with the metal ion allowing the metal ion to be expelled out.
The most common chelating agents used in water treatment is ethylenediamine whose key function is to bind all positive ions like calcium ion (Ca2+) so that they do not form insoluble particles. Not only do chelating agents soften water but they also clean stains. It is because of this reason that most laundry detergents, shampoos, and soaps contain chelating agents.
The other method which is best for maintenance and removal of all traces of calcium is chemical treatment through the water gave out is not safe for drinking.
Why Chemical treatment is more of a cleaning process than purification.
Chemical treatment is more of a cleaning agent than a purifying or softening agent. This is a process where Sodium carbonate breaks down hard water removing calcium and magnesium ions present in the water supply. It can safeguard your water system when used appropriately. However, at home, you can also try out the following options to remove calcium from the water.
- Use of a vinegar– calcium is highly reactive to acids like vinegar.
- Using a rinse aid such as semi-shine especially on dishes and glassware to minimize calcium ion and other contaminant deposits.
- Appliance cleaners are acidic, abrasive, and chlorine-based effective in removing calcified buildup in water pipe systems.
- Aquasana whole house salt-free water conditioner is a long-term, effective and more than a softener. It prevents scale formation and protects water pipes from corrosion.
Water is of two types, whose effect is considerably different. Soft water whose mineral content is low contains only sodium and hard water whose mineral quantities are high, with more calcium and magnesium to a lesser degree. Although water containing calcium ions is not harmful to humans, it can have overwhelming effects on the water system, hot water heaters, washing machines, dishwashers, and other household appliances. Now that you know how to remove calcium from water, the question is which method would you prefer? Hope this article was helpful.