So today StrategyPage has an article on water purification, and discusses a new method developed for the military.
This is done with sheets of thin, multi-layer foam material that consists mostly of cellulose (what trees are made of 0f) and a layer of graphene (a form of carbon that is extremely thin, strong and cheap) with specific bacteria. Together, this material when placed on the surface of polluted water uses sunlight and a sponge-like process to purify the water that can then be directed (by gravity) to containers.
Field tests have shown that it works and the next step is to mass produce the graphene-based biofoam sheets and distribute them widely so regional variations in water and climate can be tested and tweaks made to the composition of the sheets for different conditions.
they also discuss waterGenSpring, which extracts water from humidity, and the Lifesaver portable water bottle, and other methods that are now available to the military and civilians.
watergen for troops includes a back pack type using a battery.
More on WaterGenSpring products here.... yup. Essentially the same as a dehumidifiier, and they sell product for dehumidifying/drying too...
ah but would my civilian dehumidifier work for disaster situations? Discussion here.