Water Filtration Using Wood Fibers

 

One of the key components of living off-the-grid is an effective method of water filtration, and a team of researchers at the Swedish KTH Royal Institute of Technology has uncovered a simple and affordable way of doing that. They have developed a technique to filter water using wood fibers.

The main aim of this project is to provide clean water in refugee camps, though the method could easily be used in any setting where a green and off-grid water filtration is needed.

The team created a new material out of wood fibers and a positively-charged polymer, which binds bacteria to its surface. In this way, the bacteria in the water are removed and the water is purified. Another use for this new material is also prevention of infection, since it can be used in bandages and plasters.

However, the main aim of this project is providing an affordable and easy to use filter for a portable water purification system, which isn’t reliant on electricity. All that’s needed for it to do its job is gravity, which forces the water through it. The bacteria is removed from the water by the material, while the filter itself doesn’t cause any toxic chemicals to enter the water as is the case with many currently used on-site water filtration options.

The filter they created works on the basis of the positively-charged polymer attracting the negatively charged bacteria and viruses in the water. The bacteria which are stuck to the surface of the polymer in this way cannot get unstuck or reproduce, and they eventually die. No chemicals or antibacterial agents are used in this process, which also means that creating bacterial resistance is not an issue.

Disposal is also easy, since the wood filter can simply be burned once it is no longer effective.

Water Producing Solar Panel

Zero Mass Water, an Arizona State University startup has created solar panel which produces water as well as electricity. The device is called SOURCE and it is standalone, meaning that it does not need any wiring or water input to harvest solar energy and produce drinking water at the same time. They have been running a pilot program since 2015 to test the system, which is already installed in a number of homes and communities.

One SOURCE unit measures 30 sq ft (2.8 sq m). It is capable of generating electricity via the solar photovoltaic panel, while it also has an integrated lithium-ion for storing the used electricity. The device then uses that electricity to power a cycle of condensation and evaporation, which produces 2 to 5 liters of water a day.

The system also includes an 8 gal (30 liter) reservoir for storing the waters that’s produced. Minerals are also added to the water here to improve taste. This reservoir can also be plumbed directly to the taps inside the building in which this system is installed. To meet the full needs of the household, multiple SOURCE units can be installed.

According to the creators, these units require minimal maintenance. The system only needs a new air filter once a year and a new mineral cartridge every five years. What also makes this system so unique is that it allows people to own their own water supply for the first time. They will also be very useful in areas where there is little to no access to drinking water.

To speed up deployment in these areas the company is starting an interesting program aimed at early adopters of the tech. They will ask customers who buy one of these SOURCE panels to split the cost of an additional panel with the company. This additional panel will be given to a family or community in need, and the customer will get to choose where it will be deployed. The household to which this panel will be given will only pay for installation and shipping.

The price is set at $4800 per unit, which is made up of $3200 for one SOURCE unit, and $1600 for the additional unit to be gifted to a family or community in need. It’s a thoughtful initiative, which will hopefully help several communities gain access to clean water.

A Promising New Way to Clean Our Oceans

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It’s no secret that we don’t take care of our oceans as well as we should. In the past, there have been quite a few projects aimed at cleaning up the trash and other harmful pollutants from the ocean. The so-called Seabin Project is one such undertaking, and even though it is pretty small-scale it is nevertheless very promising. It is an invention of two surfers from Australia, who got tired of seeing all the harmful trash floating around in the water. They have recently managed to raise enough funds to start production.

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The Seabin is a type of water filtering system, which can be installed in ports, marinas and yacht clubs. It is designed to be installed on a dock and then connected to a water pump on shore. The rim of it hits at surface level of the water, and then the pump works to pull in the trash, oil and detergent floating in the water. These are then caught in a removable catch bag, which is made of natural fiber. There is also a separator filter, which cleans the oil from the water, before the water is pumped back into the ocean.

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Since the Seabin is designed for use near shore, it does not need to be high-tech or sturdy enough to withstand open ocean conditions and currents. The project is currently in the prototype stage, but having raised the necessary funds through the crowdfunding campaign on IndieGoGo, they plan to begin manufacture soon. They are also planning on manufacturing the units using the plastic collected by already installed Seabins. They estimate that the first units will be available by November 2016. The price is not yet set, though it will most likely revolve around $5000 per unit.

Cheap and Simple Way to Turn Seawater Into Drinking Water

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Shortage of drinking water is being faced by more and more communities worldwide. On the other hand, the current methods of turning salt water, which is abundant, into drinking water are expensive and damaging to the environment, and therefore not a viable long-term solution. However, a team of researchers at the University of Alexandria have recently come up with a simpler, cheaper and much cleaner method of turning seawater into drinking water. Their solution could potentially bring clean drinking water to parts of the world, such as North Africa and the Middle East, which do not have sufficient access to it.

Currently, there are several large desalination plants in operation, but these work on the basis of a multi-step process. These plants utilize the process of reverse osmosis, which needs expensive infrastructure and vast amounts of electricity to function. In addition to that, such plants also pollute the oceans by releasing back into them huge quantities of highly concentrated salt water, as well as other pollutants, which adversely affects marine environments.

This is why the method developed by the University of Alexandria team is so promising. Their method involves using materials, which can be manufactured easily and cheaply in most countries worldwide, in order to purify the water. Furthermore, the method they developed does not rely on electricity overmuch.

The tech they developed is based on a method of separating liquids and solids called pervaporation. The latter is a simple process performed in two steps. The first step is filtering the seawater via a ceramic or polymeric membrane, and the second step calls for the vaporizing of, and collecting the condensed water. This final step does not depend of electrically generated heat, which makes pervaporation a lot more energy efficient, as well as cleaner and faster than currently used water desalination methods.

Pervaporation is not a new process, but until now the membrane that is needed for it to work was very expensive and difficult to make. However, the researchers have also invented a brand new, salt-attracting membrane, which is embedded with cellulose acetate powder. This membrane is used in step one of this process, while the acetate powder needed to make it is derived from wood pulp and can cheaply and easily be made in any lab.

According to the researchers, this method can be used to quickly desalinate highly concentrated seawater, while also purifying it even if it is very contaminated. The membrane they use is also capable of capturing pollutants and salt crystals and thereby greatly reducing the polluting aftereffects of using this method. Since fire can be used as a source of heat, the method is perfectly suitable to be used anywhere in the world. All in all, this looks like a very promising solution for third world countries facing drinking water shortages.