Types of Water Treatment Systems
There are many ways to treat water. The most basic is boiling, which kills bacteria and other disease-causing organisms. However, nitrates, sulfates, and other inorganic impurities are not removed and can in fact become more concentrated. Another option is ultraviolet radiation. While UV light has germicidal properties, water conditions can interfere with UV energy transmission and reduce efficiency; and once the light is turned off, so is the means for disinfection.
Chlorination is common and inexpensive, but chlorine (while it kills most bacteria and some viruses) can react with metals and organic matter present in water. Hazardous chemicals can form in the process. Other methods include pasteurization and distillation, but each has its complexities and limitations compared to effective filtration types such as:
Mechanical Filters
A mechanical filter removes sand, clay, silt, organic matter, and other suspended materials. Typically made of fiber, fabric, or ceramic, these filters are often cartridges that mount to a tap, waterline, or tank.
Activated Carbon Filters
The primary purpose is to absorb impurities, chlorine, organic compounds, odors, and tastes, but carbon does not filter out most inorganic chemicals, metals, nitrates, or microorganisms. However, they can remove many dissolved organic chemicals and radon gas.
Reverse Osmosis (RO) Filters
Impure water is forced through a semi-permeable membrane that removes impurities, which are flushed down the drain. Pre and post filters improve contaminant removal. An RO filter can remove metals, salts, minerals, and most inorganic chemicals; many organic chemicals; and most microorganisms.
Oxidizing Filters
When a water softener isn’t desirable, these remove iron, manganese, and hydrogen sulfide that creates a rotten egg odor. Oxidizing filters are suited for treating a whole house water supply.
Neutralizing Filters
Designed to treat acidic water, neutralizing filters pass water through limestone chips or another agent. This avoids the potential for copper, lead, and other toxic metals to leach into the water supply.
Sediment Filters
Used for well water and municipal water supplies, sediment filters get rid of grit and particulates that can clog other water filters, plumbing pipes, and water-using appliances.
Ion Exchange Filters
These water softeners remove minerals like calcium and magnesium, which can cause scale buildup in pipes, plumbing appliances, and fixtures. As water is pumped through a resin, sodium replaces minerals present in the water. An ion exchange filter can also remove iron, manganese, and heavy metals.
