How about a simple 2 stage RO ...
Published by Paul Jacob, Asian Institute of Technology (AIT) - Research Associate
How about a simple 2 stage RO system (with activated carbon filter), they are commercially available as a package system. Various sizes are available at household levels. This is if electricity is available. But if you planning to do research then we can speak more. If you can give the details of the water quality. In the past we developed a hand driven membrane system for emergency situation. But I am not sure heavy metal can be removed by such system. As its a UF based system. I think this problem seems to be interesting. Hopefully you can share more info.