I think it's impossible to know the best method without a field search.

For exemple, in Brazil we are successfully using the reverse osmosis for desalination, however this is expensive.

There is a very simple method, using PET bottle and solar radiation. Click this link to see: http://g1.globo.com/jornal-nacional/noticia/2014/12/agricultores-do-agreste-aprendem-purificar-agua-com-metodo-simples.html

Thanks for your answer Mariele. I appreciate it.

It depends on many factors such as source water quality, desired treated water quality, available money.....

For example, if the water source is sea, then we can say best available is RO in case of low cost energy source availability. In case it is small and poor household in a resort area, the best option may be solar distillation.

If the water source is a river with good quality water, then it may be conventional water treatment (Coagulation, sedimentation, Rapid sand filtration, chlorination would be best and low cost.

..........

Parmod Kumar , I just remember, we worked several years ago on water treatment with membrane filtration. the same company has developed technology suitable for African countries. please see the links.

http://www.metawater.co.jp/eng/news/2013/0703.html

http://www.metawater.co.jp/eng/news/2012/0906.html

our joint publications:

Article Long-term studies on hybrid ceramic microfiltration for trea...

Article Removal of DOM and THM formation potential of tropical surfa...

this is a low cost method with less power consumption:

Chapter Chemical-free and carbon neutral membrane based emergency wa...

Solar distillation can be used.

Everything depends upon water quality to be treated. According to pollution of water the treatment technology must be chosen.

Best regards

Vit

The treatability of water is highly dependent on the characteristics (quality) of the source water. If the water is well characterised, then appropriate technologies can be used to treat it to the desired quality.

Best regards

Samuel

P&G makes water purification packets for drinking water on a small scale or in emergencies. https://csdw.org/ The flocculation and disinfection process gets rid of dirt, viruses, and bacteria, but it may not get rid of oil or solvents.

Solar distillation can be used.

Sand filtration.

I agree with Dr. Afraa Ibrahim for your answer.." The most important means of water treatment in the present time in an environmentally friendly way is the use of ultrasound (ultrasound), devices that give ultrasonic waves that are transmitted through the water at frequencies that exceed the possibility of human hearing and these waves kill lichens, algae and sino bacteria in the water, which cause a lot of diseases for humans In addition To its bad smell and thus reduce the use of chlorine water by up to more than 60%. Ultrasound is also used in lakes and fish farms for the same task, so the water remains clean, full of oxygen, creating a healthier environment where fish can grow better".

One of the simplest way is to expose thin layer of water to UV light (sunshine) combined with filters of active charcoal. You could also envisage artificial ponds were particles could sediment and heavy metals could be absorbed by plants such as: Eichhornia crassipes, Typha domingensis, Typha latifolia, Phragmites australis or Juncus maritimus.

Lifesaver bottle is one of the best solutions for individual. For group usage, I suggest our M2Q+Membrane System. What is M2Q? Please watch the video on youtube ( https://youtu.be/7iO_yfZURXw ) . M2Q is every efficient to treat all kind of water. It is much more easy to treat as drink water with many other technique then.

I agree with Jean-Pierre Jost answer...

Vit Mateju, Samuel Nyarko, Richard Ammel, Omar Al-Khashman, Afraa Ibrahim, Laura Bulgariu, Jean-Pierre Jost, and Wei Huang do you have any suggestion on making a comparative analysis of different techniques for water purification?

Slow Sand filtration

Membrane methods are the most effective and fouling can be mitigated. The most robust systems are Reverse Osmosis since they are the most used in the world. Water treatment from seawater is best achieved by Reverse Osmosis.

In Africa there is a lot of sun radiation, the economical method is solar distillation.

Dear Parmod,

Before economical comparison of various water purification technologies, you need to clarify the volume of water that needs to be treated, as well as, the contamination level of water source.

I agree with Behnami. The contaminants present in the source of water is going to play an important role in the choice of the process of purification.

Valuable discussion.

I can say Solar Disinfection

High efficiency, cheap investment and lower running cost, easy to operate are most important facts for Africa. Sand filter is not powerful enough to generate the drink water, however it could be good at pre-treat. Membrane is good at the rest job. Solar offers the energy, and the unit is much cheaper now. Removable Bioreactor Unit is good enough to treat all kinds of wasted water, including landfill leachate. Further jobs are needed to treat some special industrial water, for instant mining... As I mentioned in my previous post, M2Q is a good way to treat heavy dirty water. Please refer https://youtu.be/7iO_yfZURXw It has been designed in the unit.

The most important systems are Reverse Osmosis since they are the most used in the world.

It totally depends on source water quality. If you generalize it then it won't be cost effective. Once you know the impurities and its concentration then its very easy to find out best possible and cost effective solution. Field research is required.

Yes, it depend on the quality of water uses, and it use the high efficiency, cheap investment and lower running cost and easy to operate .

Solar distillation.

Laser based secondary treatment

Method of treatment of water for drinking purposes in a economic way, solely depends on the quality of source water. This gives the idea of types and the level of occurrence of contaminants to be removed. Accordingly, treatment method could be selected. Due to variation of quality of source water no particular method could be applied in all areas. In case of surface water like, ponds, lakes, streams, rivers the most feasible and economic method would be simple sand filter with activated charcoal. In case of sea water, solar distillation might be employed.

@ Abhijit Mitra

What could be " LASER based secondary water treatment technology" based on ?

Is it a method based on killing the microbes with LASER ?

Something similar to chlorination ?

With regards,

ARB

Magic beans. They will work in any type of "Africa water", regardless of whether you're trying to remove radioactivity, nitrates, pesticides, salt, or pathogens. Plus, they're reusable, so after you find a mysterious old peddler and trade a cow for the beans, there's no additional investment!

Ask a silly question and you get a silly answer.