How to Make an H20 Filter Out of Materials You Already Have Around the House
Learn how to make an emergency water filter out of materials you already have around the house. This is not designed to make potable water, but it does work and could keep you heathy in a disaster situation.
Researchers at MIT have created a natural water filter using the sieving ability of xylem, the thin membranes that carry water through a plant’s branches. They’re hoping the simple, low-cost method could help reduce harmful contaminants in drinking water.
1. Reverse Osmosis
Reverse Osmosis (RO) is one of the most effective home water filtration systems. It uses a semi-permeable membrane to separate clean drinking water from other contaminants. The resulting pure, healthy water is usually stored in a storage tank under the sink where it can be dispensed directly into your tap.
Essentially, RO works by applying pressure to the salt side of the membrane, which creates osmotic pressure. That pressure forces water molecules through the membrane while leaving almost all dissolved minerals, organics and bacteria behind in the reject stream.
This process also removes harmful contaminants like disinfection byproducts, volatile organic compounds, nitrate and hexavalent chromium, lead, arsenic, PFAS and more. However, the contaminant-free RO water can be susceptible to biological contamination, known as biofouling, which requires additional filtration to prevent.
Home RO systems typically use three to five filters to achieve the level of purity you desire. For example, RO systems can reduce up to 99% of asbestos and cysts, 95% of chlorine and hexavalent chromium, and 90% of lead, fluoride and other dangerous contaminants.
2. Activated Carbon
Activated carbon is a versatile and effective filtering material. It can remove contaminants from water through physical adsorption (which occurs when the contaminants stick h20 filter to the surface of the carbon molecules) and chemical reactions.
Depending on the specific chemical being removed, one type of activated carbon may be more effective than another at removing it. This is because the size and structure of the carbon particles can determine how much chemicals are adsorbed.
Other factors that influence the adsorption process include the water temperature and the pH of the solution. For example, organic chemicals tend to be less adsorbable at higher temperatures and lower pH levels.
There are several types of activated carbon available for use in h20 filters. Powdered activated carbon (PAC) and granular activated carbon are the two most common. PAC is made from coal, but it can also be impregnated with metal oxides for specific air and water applications. For instance, copper impregnated PAC removes acid gases such as ammonia and amines while phosphate-impregnated carbon targets radio-active iodine, arsenic, and mercury.
3. Carbon Block
Carbon block is a point-of-use water filter technology and can work as standalone or in conjunction with other technologies like reverse osmosis. It is made of compressed activated carbon and is ideal for removing chlorine, unwanted odors, volatile organic compounds and other impurities from drinking water.
The most important consideration when purchasing a carbon block is the source material. This determines the quality and effectiveness of the carbon block. The best sources of raw carbon are bituminous coal, wood and nutshells (specifically coconut shells).
When purchasing a carbon block it is also important to consider the micron rating and pore size. A carbon block’s pore size and shape determines its ability to remove specific contaminants, such as heavy metals and toxins.
A carbon block’s filtration process involves physical and electrokinetic adsorption. Physical filtration is achieved through mechanical adsorption which works much like a sieve, wherein particulates with a larger particle size are strained out, while smaller particles are trapped by the carbon. The more adsorbent the carbon, the greater the reduction of contaminants. The uniform pore structure of carbon blocks allows for more contact time between the contaminants and the carbon, further increasing its ability to remove them.
4. Granular Activated Carbon
Granular activated carbon, or GAC, is a high-purity form of activated carbon used in many liquid and gas purification applications. It has a high surface area, with particle sizes from 0.2mm up to 5mm. It is available in a variety of physical forms, including powder activated carbon (PAC), extruded block activated carbon (EAC) and bead-shaped granular activated carbon (BAC).
Activated carbon has the ability to remove organic chemicals from water. Those chemicals are typically responsible for objectionable odors and tastes in drinking water. This is because Activated Carbon absorbs them by trapping them in its microscopic pores.
The pores in Activated Carbon are created by heating raw carbon-containing organic materials, such as coal, lignite, wood, coconut shells or peat. The resulting material has a randomly h20 filter supplier porous structure with pore sizes from visible cracks and crevices to molecular dimensions, giving it a high surface area.
As chemicals pass through the adsorbent, they take up space on its surface and eventually deplete its adsorption capacity. To keep it functioning at peak performance, a GAC filter needs to be regularly reactivated.
5. UV Light
While our filtration systems eliminate many contaminants and chemicals, sometimes bacteria, viruses, and other harmful microorganisms can make it past the filters. These microorganisms can cause many serious health problems including diarrhea, meningitis, and hepatitis A. UV light uses nonthermal, nonchemical intervention to inactivate these harmful organisms by emitting physical light energy at specific wavelengths. These wavelengths are called UV-A, UV-B, and UV-C. UV-C, which is the most germicidal wavelength of all, kills bacteria by causing DNA mutations in their cells.
Ultraviolet lights are commonly used as part of or in conjunction with water treatment systems. They can be installed in a wide variety of applications, including bag filtration, cooling tower filtration, and media filtration.
In addition to being effective at killing a wide range of microorganisms, UV-C sterilization is also effective at eliminating some parasites like cryptosporidium and giardia. These are common in public water supplies and can be especially dangerous for immunocompromised individuals. Because these parasites are resistant to chlorine and other chemical disinfectants, they must be killed using a UV sterilizer.
