Softening Process
The water is treated by using resin bed. Water is passed through bed of the resin where negatively-charged resins absorb and bind positively charged metal ions. The resins which consist of univalent sodium or potassium ions get exchanged with divalent calcium and magnesium ions in the water. The exchange of ions prevents precipitation and formation of soap scum. More and more odium or potassium ions are released from the resin into the water if it's degree of hardness is more.
Mineral tank and the brine tank are the main constituents of the water softening system. The water softening system consists of a mineral tank and a brine tank. The mineral tank and the water supply pipe is connected due to which water passes through the tank before it can be used. Mineral tank consist of negatively charged beads or resins that attracts positively charged calcium and magnesium.
The surface of the resin gets coated with the calcium and magnesium minerals. The resin is cleared by flushing a strong sodium (salt) solution held in the brine tank. The sodium ions are powerful and they easily overpower the calcium and magnesium ions and drives them off of the resins which is later drained out of the unit.
Types of Water Softening Equipments
Manual
These can be controlled and operated manually. The frequency, rate and time length of backflushing is controlled by the operator by opening and closing of the valves.
Semi-automatic
In this type of equipment only the recharging cycle is initiated.
Automatic
Automatic equipment is equipped with timer that automatically initiates the recharging cycle and every step in the process. For this only timer is needed to be set by the operator.
Demand initiated regeneration (DIR)
It is an automatic system consisting of two softening tanks and a brine tank. One of the tank is for softening whereas other is for recharging.
Off-site regeneration
A used softening tank is physically replaced with a recharged tank. Spent softening tanks are then recharged at a central location.
Operation and maintenance
The brine tank should be cleaned regularly. The cleaning frequency depend on the amount and purity of the salt used in the softening process. Brine valve and float assembly are important parts hence their regular check up is necessary.
Excess iron or hydrogen sulfide's presence can affect the effectiveness of a water softening unit. Hence back-washing should be done frequently or reversing the normal flow of water by the treatment unit in order to remove iron buildup.
Water Softener Types