Ground and surface water – even if it looks clean at first glance – is not suitable for drinking without treatment. The water may contain many invisible pollutants and germs such as coli bacteria or suspended solids that are not good for the human body. Too high a concentration of nitrate, caused by agriculture, can also often be detected in groundwater.
Whether hiking, camping, or traveling in other countries, before water is safe for human consumption, it should always be carefully purified. Otherwise, the risk of gastrointestinal diseases due to germ-contaminated water is too great and can quickly put an unwanted end to a trip.
Probably the best known method of water purification is boiling. The mechanism is quite simple: as soon as the water is strongly heated and bubbles, bacteria, viruses, parasites and other germs die off. Especially in the outdoor kitchen when camping, this method is very popular, because usually anyway a gas stove is part of the equipment.
Boiling water is a proven method that does not require chemical additives and is also very inexpensive. The water should definitely boil for a while so that germs are really reliably killed.
Unfortunately, boiling does not help rid water of pollutants such as heavy metals and salts. Also, a bad smell or a strange color of the water is not usually eliminated by boiling. In addition, heating water – especially in larger quantities – is very time-consuming: With a small gas stove, it takes quite a while to produce enough drinking water.
Another popular method of water purification is the use of water filters. Depending on their composition and pore size, these can filter out impurities and coarse particles such as algae, suspended matter and bacteria. Even if there is lead in the drinking water or other heavy metals are present, a high quality water filter can successfully filter out these substances.
Ideally suited is the use of water filters on the road when hiking, traveling or camping. But even at home, a backup water filter is always useful.
Basically, if a high-quality water filter is used, it is sufficient for the treatment of water in natural areas. However, if water from questionable water sources, for example in highly populated areas, is to be made drinkable, additional disinfection by tablets may be necessary.
How does a water filter work anyway? Depending on the design, materials and composition, water filter models have different modes of operation.
Activated carbon filter
Activated carbon filters treat water by passing it through a block of activated carbon. With its adsorptive effect, this ensures that the impurities are bound and “absorbed”. At the same time, the filter also cleans through a mechanical and catalytic action.
High quality activated carbon filters are ideal for removing harmful substances from water. The filtering effect works for a wide variety of substances. For example, they filter:
- Heavy metals
- Germs and bacteria
An activated carbon filter often also removes minerals from the water. The quality of the filter determines whether important minerals that are useful for drinking water remain in the water or are filtered out. For example, activated carbon granules filter valuable minerals and trace elements out of the water – activated carbon block filters , on the other hand, leave these in the water and are therefore more suitable for purifying drinking water.
Doesn’t a filter that only binds certain substances in the water pose a certain health risk? The following applies here: high product quality and the perfect condition of the filter are decisive. As soon as the storage capacity of the activated carbon is exhausted, the filter cartridge must be replaced. Less than 0.3 µm is considered absolutely germ-proof, as bacteria cannot enter the filter outlet. This includes our high-performance SUPERPURE filter.
Reverse osmosis systems
Osmosis water is produced through a semipermeable membrane. When two liquids with different particle concentrations are separated by such a membrane, the so-called osmotic pressure is created. The two fluids then strive to equalize the concentration of particles.
Reverse osmosis works on the reverse principle: the contaminated water has a higher concentration of particles and is forced onto the semipermeable membrane from the outside at high pressure. This filters out contaminated substances and allows only the clean water particles to pass through.
The semi-permeable membrane filters substances such as nitrate, heavy metals, phosphate, but also vital minerals out of the water. What remains is highly pure water that can even be used for laboratory purposes.
Reverse osmosis filters are among the most expensive water filters. Osmosis water, for example, is said to contain among the fewest pollutants and even to be successfully free of drug residues. Nevertheless, there are always warnings against drinking osmosis water.
The main criticism of a reverse osmosis system is the fact that the filter technology also filters valuable and vital minerals out of the water. These include, for example, trace elements such as zinc, iron or magnesium, which are found in normal drinking water. Osmosis water can therefore lead to a possible undersupply of nutrients, according to some experts. However, remineralization following water purification can usually solve this problem successfully.
Another problem with reverse osmosis systems is the risk of dangerous germs multiplying if the filter or osmosis membrane is not changed regularly. In addition, reverse osmosis technology is criticized for producing wastewater. To obtain one liter of clean osmosis water, about three liters of water must be filtered.
Similar to the reverse osmosis system, ultrafiltration also works with a membrane technology. In this process, even macromolecular substances and tiny particles can be removed from the water. An extremely small pore size of 0.1 µm ensures that even microbiological contamination is retained.
Portable water filters in particular often use ultrafiltration technology. Although this successfully filters out most undesirable foreign substances, the technology also has a disadvantage: the flow rate is extremely low due to the small pore size. So, to filter a sufficient amount of drinking water, a lot of time is needed. Larger ultrafiltration plants therefore operate with a high working pressure with which the water is pressed onto the membrane.
Supplements & Tablets
Water purification via additives does not filter the water, but eliminates bacteria, viruses, fungi and other germs. This disinfection effect only works reliably with water that is already clear – the additives can do little against turbidity and chemicals. In many cases, it therefore makes sense to combine water filters with tablets to obtain a particularly pure and long-lasting result. As a rule, the water is first coarsely filtered so that water sterilization can then be carried out with the aid of additives.
Tablets for water disinfection, for example, are based on silver ions combined with chlorine. Thus, the water can be preserved for up to six months. An unpleasant side effect: with some products, a chemical water taste can remain after cleaning. The long exposure time of some products can also be annoying in the long run.
UV light is a safe method to inactivate microorganisms such as bacteria, viruses and protozoa from drinking water. To do this, a handy UV filter in the form of a stick is held in the water for a few minutes. This method is particularly suitable when large quantities of water are not required and disinfection is to take place quickly.
UV disinfection also does not filter out turbidity or chemicals from the water. This must already be clear before preparation or must first be filtered. In contrast to chemical water disinfection, the odor and taste of drinking water remain unchanged.
Each variant of water treatment brings advantages and disadvantages. In the end, it can be said that a combination of the various options is the most sensible solution for obtaining clean drinking water.