Direct contact membrane distillation (DCMD). Applicable to desalination. Heated seawater is passed along the surface of a hydrophobic polymer membrane. Evaporated water passes from the hot side through pores in the membrane into a stream of cold pure water on the other side. The difference in vapour pressure between the hot and cold side helps to push water molecules through.

Distillation involves boiling the water to produce water vapour. The vapour contacts a cool surface where it condenses as a liquid. Because the solutes are not normally vaporised, they remain in the boiling solution. Even distillation does not completely purify water, because of contaminants with similar boiling points and droplets of unvapourised liquid carried with the steam. However, 99.9% pure water can be obtained by distillation.
After Hurricane Sandy, many homeowners used portable generators to replace lost power, leaving the machines running overnight and allowing odorless carbon monoxide to waft inside. The gas induces dizziness, headaches, and nausea in people who are awake, but "when people go to sleep with a generator running, there's no chance for them to realize that something's wrong," says Brett Brenner, president of the Electrical Safety Foundation International.
America's national pastime may seem a gentle pursuit, but it is not without its fatal hazards. The 2008 book Death at the Ballpark: A Comprehensive Study of Game-Related Fatalities, 1862–2007 catalogs deaths that have occurred while people were playing, watching, or officiating at baseball games. Among the causes is commotio cordis, a concussion of the heart that leads to ventrical fibrillation when the chest is struck during a critical 10- to 30-millisecond moment between heartbeats. About 50 percent of all victims are athletes (and the vast majority of these are male) engaging in sports that also include ice hockey and lacrosse, the U.S. National Commotio Cordis Registry reports.

The practice of water treatment soon became mainstream and common, and the virtues of the system were made starkly apparent after the investigations of the physician John Snow during the 1854 Broad Street cholera outbreak. Snow was sceptical of the then-dominant miasma theory that stated that diseases were caused by noxious "bad airs". Although the germ theory of disease had not yet been developed, Snow's observations led him to discount the prevailing theory. His 1855 essay On the Mode of Communication of Cholera conclusively demonstrated the role of the water supply in spreading the cholera epidemic in Soho,[39][40] with the use of a dot distribution map and statistical proof to illustrate the connection between the quality of the water source and cholera cases. His data convinced the local council to disable the water pump, which promptly ended the outbreak.
People love the quick, easy operation of the Zip Reverse Osmosis Water Filter and the fact that they don’t have to install anything or run hoses to the tap. The convenience of a reverse osmosis system for apartments doesn’t come cheap though. Still, this is one of the sleekest, most portable reverse osmosis systems we’ve seen. Whether you’re a renter or looking for a mobile water filtration system, the Zip is a great choice.
Use a commercial water filter. A commercial water filter is the easiest and most effective way to filter sediment, pathogens, metals, and other pollutants from water. These filters contain special materials like charcoal, carbon, ceramic, sand, and cloth that are specially designed to filter out dangerous pollutants.[7] There are many different types of filters you can use, including:
Distillation is a water purification method that utilizes heat to collect pure water in the form of vapor. This method is effective by the scientific fact that water has a lower boiling point than other contaminants and disease-causing elements found in water. Water is subjected to a heat source until it attains its boiling point. It is then left at the boiling point until it vaporizes. This vapor is directed into a condenser to cool. Upon cooling, vapor is reversed into liquid water that is clean and safe for drinking. Other substances that have a higher boiling point are left as sediments in the container.

The EPA states that there are four main types of contaminants to be found in water. The Safe Drinking Water Act (SDWA), a federal law that protects public drinking water supplies, defines "contaminant" as anything other than water molecules. We can reasonably expect most drinking water to contain some level of contaminant, especially since minerals such as calcium and magnesium fall into that category. The question is, which of these contaminants are harmful and how much of it is entering my system?


Drinking water sources are subject to contamination and require appropriate treatment to remove disease-causing agents. Public drinking water systems use various methods of water treatment to provide safe drinking water for their communities. Today, the most common steps in water treatment used by community water systems (mainly surface water treatment) include:
Storage – Water from rivers may also be stored in bankside reservoirs for periods between a few days and many months to allow natural biological purification to take place. This is especially important if treatment is by slow sand filters. Storage reservoirs also provide a buffer against short periods of drought or to allow water supply to be maintained during transitory pollution incidents in the source river.

Water filters can come in smaller, portable forms which are convenient for travel and outdoor activities. Those who go hiking and backpacking often come across bodies of fresh water such lakes and rivers. While lakes and rivers are considered fresh in comparison to the seawater, they still need to be filtered before drinking due to the presence of sediment and potential bacteria. Having a portable water filter handy will eliminate the worry of ingesting harmful contaminants such as bacteria, parasites, sedimentary rock. Read our article on portable water filters for a detailed guide on how they work and which brands to use.

I'm Jeremiah Castelo, the owner of World Water Reserve. I'm a writer and researcher with a particular interest in sustainability and rural living, water scarcity, and innovative water purification methods. I utilize my multimedia and communication experience in the NGO and humanitarian fields to bring light to important topics. My passion is to educate others on the reality of the global water crisis and on ways to sustain themselves and their families in the midst of it.
Desalination – is a process by which saline water (generally sea water) is converted to fresh water. The most common desalination processes are distillation and reverse osmosis. Desalination is currently expensive compared to most alternative sources of water, and only a very small fraction of total human use is satisfied by desalination. It is only economically practical for high-valued uses (such as household and industrial uses) in arid areas.

Reverse osmosis per its construction removes both harmful contaminants present in the water, as well as some desirable minerals. Modern studies on this matter have been quite shallow, citing lack of funding and interest in such study, as re-mineralization on the treatment plants today is done to prevent pipeline corrosion without going into human health aspect. They do, however link to older, more thorough studies that at one hand show some relation between long-term health effects and consumption of water low on calcium and magnesium, on the other confess that none of these older studies comply to modern standards of research [27]
This water filtration system has 7 stages of treatment, including an 11-watt UV light to zap any microorganisms that may be lurking in well water. While this isn’t usually a major concern for homeowners on municipal water, the conditions of a well sometimes harbor bacteria and microorganisms that could pass through your plumbing and into your glass. A UV sterilizer is an efficient, effective way to eliminate this risk and have more peace of mind when drinking well water.

This water filtration system has 7 stages of treatment, including an 11-watt UV light to zap any microorganisms that may be lurking in well water. While this isn’t usually a major concern for homeowners on municipal water, the conditions of a well sometimes harbor bacteria and microorganisms that could pass through your plumbing and into your glass. A UV sterilizer is an efficient, effective way to eliminate this risk and have more peace of mind when drinking well water.
Electrodeionization:[11] Water is passed between a positive electrode and a negative electrode. Ion exchange membranes allow only positive ions to migrate from the treated water toward the negative electrode and only negative ions toward the positive electrode. High purity deionized water is produced continuously, similar to ion exchange treatment. Complete removal of ions from water is possible if the right conditions are met. The water is normally pre-treated with a reverse osmosis unit to remove non-ionic organic contaminants, and with gas transfer membranes to remove carbon dioxide. A water recovery of 99% is possible if the concentrate stream is fed to the RO inlet.
Furthermore, animals have to drink and are known to visit water holes. This raises several concerns, 1) Animals are not very mindful of their toilet etiquette and 2) Predators will sometimes use water holes as a place of attack. If we were desperate, (dying of thirst) and had no way to purify the water, first we really should ask ourselves how we got ourselves into such a situation, then we would have no choice but to drink the water in hopes that we are rescued before the water borne disease kills us. Think outside the box, is there a way to get a makeshift bowl (wood, vegetation) and use hot rocks to boil the water. Is there any material around, bamboo etc that can be used to slowly bring the water to a boil. Build a multiple stage filter using sand, charcoal and sphagnum moss which has been known to contain some levels of iodine. If all that fails then we would be faced with the choice of drinking the untreated water. We know that moving water is preferable to standing water, but what can we do. We can walk around the water source, find the area with the least animal traffic and preferably a sandy shoreline. We can then dig a hole near the water deep enough to allow water to collect. The distance from the water source will have to be judged by the soil we are digging. The hope here is that the water will slowly seep into the hole and begin to collect while being "filtered" by the sand and rocks. At this point we have to get creative to get the water out. Perhaps make a straw out of natural materials or simply soak a bandana and squeeze it into our mouth. This would be a last resort and very risky.
I've just finished installation of your 5 stage home drinking reverse osmosis system and I have a few suggestions for improvement. It looks like the faucet included in the package is different than the one in the instructions. I like the upgrade, but it would be nice if you included a compatible quick connect adapter. The Quick Connect adapter that was included (pictured on the right) has threading that is too large to fit on the faucet. The packing nut attachment doesn't work well with plastic tubing.
Desalination – is a process by which saline water (generally sea water) is converted to fresh water. The most common desalination processes are distillation and reverse osmosis. Desalination is currently expensive compared to most alternative sources of water, and only a very small fraction of total human use is satisfied by desalination. It is only economically practical for high-valued uses (such as household and industrial uses) in arid areas.

Granular Activated Carbon adsorption: a form of activated carbon with a high surface area, adsorbs many compounds including many toxic compounds. Water passing through activated carbon is commonly used in municipal regions with organic contamination, taste or odors. Many household water filters and fish tanks use activated carbon filters to further purify the water. Household filters for drinking water sometimes contain silver as metallic silver nanoparticle. If water is held in the carbon block for longer periods, microorganisms can grow inside which results in fouling and contamination. Silver nanoparticles are excellent anti-bacterial material and they can decompose toxic halo-organic compounds such as pesticides into non-toxic organic products.[24] Filtered water must be used soon after it is filtered, as the low amount of remaining microbes may proliferate over time. In general, these home filters remove over 90% of the chlorine available to a glass of treated water. These filters must be periodically replaced otherwise the bacterial content of the water may actually increase due to the growth of bacteria within the filter unit.[13]
I love this new ro system, I've never installed one of these before but luckily the dvd walked me through it step by step. With the Ppm meter they gave me I tested my water for the first time before and after. My ppm went from 275 to 8. I’m very pleased so far. Easy to install and I'm loving it ! Thank you so much for providing a great quality product with a simple set up for great tasting water :)

I'm Jeremiah Castelo, the owner of World Water Reserve. I'm a writer and researcher with a particular interest in sustainability and rural living, water scarcity, and innovative water purification methods. I utilize my multimedia and communication experience in the NGO and humanitarian fields to bring light to important topics. My passion is to educate others on the reality of the global water crisis and on ways to sustain themselves and their families in the midst of it.
While reverse osmosis systems are widely used for industrial and commercial purposes, smaller home units can be purchased and installed under the kitchen sink and dispensed through the faucet. Home RO units typically run on a 3-stage system which includes a carbon filter, RO membrane, and re-mineralizing filter for taste. Some systems can include 5, 7, or even 10 stages. While the additional stages offer extra benefits such as pH level balance and UV filtration, a simple 3-stage system has everything required to produce pure, drinkable water. RO systems require frequent maintenance and replacement of filters in order to keep it functioning properly. Read our article on reverse osmosis systems for home use for a detailed guide on how they work and which brands to use.
The remineralization stage is an additional feature of this water purifier. The name itself explains the function of this stage. After passing through the basic 5 stages of filtration the water is treated in the remineralization stage. At this point of purification, some advantageous minerals restored into the water again. The added minerals improve the taste and raise the pH to more alkaline. You will definitely enjoy the fresher tasting mineral water.
×