Popular Methods Used in Water Purifying Systems
Most people know of water purifying systems as water filters they install at home. Those water filters use the process of carbon adsorption to strain unwanted contaminants in water to make it fit for human consumption. However, other water purification systems also exist aside from filters. They eliminate chemicals, debris, algae, bacteria, fungi, parasites, and other contaminants to meet the standards of water quality for drinking, medical use, and industrial application. Understanding the different water purification methods bring clarity to making decisions regarding the best system to use.
Distillation
The oldest method of water purification, distillation purifies water through a process of boiling, vaporization, condensation, and collection. Since water converts into three forms of matter, distillers assume its chemical composition remains so after condensing and turning into liquid again. However, they were unaware that distilled water loses oxygen and trace minerals after distillation. Thus, distillation produces flat-tasting water, which is very acidic and mostly applicable to industrial processes.
Carbon Adsorption
The most common purification method, carbon adsorption is the process used by home water filters to remove unwanted contaminants. The activated carbon effectively removes chemicals like chlorine, gases, and microorganisms. It can even get rid of bad tastes and odors. However, the process cannot eliminate heavy metals, such as lead, and coliform. To produce purified water, effective water filters use carbon adsorption along with the process of reverse osmosis.
Reverse Osmosis
The most inexpensive purification method, reverse osmosis can practically remove up to 99 percent of contaminants. Its membranes have tighter pores than ultra filtration and sieve particles, bacteria, and organics at greater than 300 daltons molecular weight. The process effectively eliminates dissolved solids, asbestos, lead and other hazardous heavy metals, radium, and other dissolved organics. Because of its effectiveness and practicality, reverse osmosis is used by most water bottlers.
Ultra Violet (UV) Radiation
Laboratories and hospitals often use UV rays to disinfect an area or equipment. The process also effectively treats water by killing microorganisms in it. Wavelengths of UV light emitted by special lamps adsorbs into the DNA of the microbial cell, which becomes inactive. In effect, the UV treatment is so strong it results to only five parts-per-billion of total organic carbon (TOC). As an industry standard, the TOC significantly shows a large amount of dissolved carbon dioxide and acidic salts disappeared from the total carbon content in water.
Water Purifying Systems Often Use Several Methods
Because each of the methods mentioned effectively eliminates only a few contaminants, most purifying systems usually combine two or more methods for water purity to reach industrial standards. At the heart of most purification systems is reverse osmosis, which effectively eliminates more contaminants than other methods. Before reverse osmosis, however, water first goes through carbon adsorption, which removes chlorine, gases, and other particulates. Softening agents added to the water removes minerals that make it “hard.”
The last step in water purifying systems is polishing, which removes traces of contaminants that previous processes failed to eliminate. For polishing, water goes through several methods, such as activated carbon filtration, mixed-bed deionization, and ultra filtration. Polishing practically raises the classification of pretreated water to “Type 1″ or ultrapure water, which is practically free of ionic, organic, and microbial contaminants.
