Today, we call ourselves highly developed and with the growth of industrial sector pollution has growth to a whole new level. A Huge amount of pollution leads to contamination and contaminated water leads to diseases. So now the question here is can the old basic filtration methods still produce the best drinking water or we need something else? Are more intense purification methods to combat the modern contaminants in our water supply needed?
The answers to these questions could be found by analyzing and comparing the traditional and modern water filtration methods.
Traditional Water Filtration Methods
From ancient times, boiling is what has been used to disinfect water from microorganisms. In fact, when done correctly, it can kill most bacteria, but not all. Bacteria and protozoa are killed at the first bubble, and it takes about three minutes to kill the rest.
However, there are a few drawbacks here.
- It can require lots of fuel and cooking equipment.Water cannot be used immediately, as it needs to cool down.Since the boiling water is so hot, some of the water may evaporate before its use.
- The water can still contain particles. So further filtering through a handkerchief could be necessary.
- Finally, boiling water does not eliminate chemical pollutants (including chlorine), poor taste of foul odors, and in fact, can leave a stale taste.
There are two primary chemicals used to purify water: iodine and chlorine. Both these chemicals are lightweight, low cost and easy to use. Iodine has been proven effective in killing off viruses, bacteria, and protozoa. However, the colder the water is, the more time it will take to purify with iodine. Iodine can also absorb into the dirt and debris naturally found in water, so the dosage will always vary. Also, pregnant women or those with thyroid conditions cannot drink water with the chemical. Usually, iodine is just used for short-term purposes, and should not be used for more than three consecutive months. Also, it leaves a taste behind that is not favored by many.
Chlorine bleach is the second chemical purifier. The process of chlorination causes dirt and debris to settle to the bottom of the water container and making the water visually clearer. When using bleach to purify, it is recommended that one adds 16 drops of bleach per gallon of water, stir, and let stand for 30 minutes. If the water does not have a slight bleach odor, one needs to repeat the dosage and let stand another 15 minutes. There are many drawbacks to the chlorination method. If the household bleach is over six months old, it may not have enough potency to disinfect. Also, chlorine is very poisonous and adding too much can cause illness, internal organ damage or even death. Chlorine has been linked to many health problems. Also, if one decides to use bleach, be sure to add it at the time intended to use the water, not when storing.
Seeing the drawbacks of these traditional filtration methods brings us to understand why more advanced water purification are required nowadays.
Advanced Modern Water Purification Methods
Water filtration by definition simply means to strain out the impurities from a water source. It is believed that larger the impurity particulate, the easier it is to filter. However, the truth is the smaller the impurity particulate, the harder it is to remove. Thus, the size of the filter pore and the durability of the filtering element are important to the filter’s longevity and its ability to perform. Most filtering elements are made of ceramic, glass fiber, hard-block carbon, or materials that resemble compressed surgical paper.
Some of the better purification methods include the activated carbon and reverse osmosis or what we call as RO water purification in general. The best contribution that carbon makes to filtration technology is its ability to reduce chemical quantities, poor taste, odors and many pollutants. Because carbon is only mildly effective in filtering out particulates and microorganisms, it is mostly used as a second or third stage filter in a home and portable water use. It is seldom used as a stand-alone filtering, and often times, used in conjunction with reverse osmosis. Reverse osmosis, which uses a semi-permeable membrane filter to separate the water from contaminants.
Reverse osmosis is highly effective in removing several impurities from water such as total dissolved solids, turbidity, asbestos, lead and other toxic heavy metals, radium, and many dissolved organic. The process also removes chlorine and nuclear radiation such as radioactive plutonium or strontium in the drinking water.
Therefore, reverse osmosis combined with activated carbon seems to be the most advanced water purification method developed till date.