Treatment Technology and Alternative Water Resources

At this point in our settlement of the planet Earth, with over seven billion human inhabitants, there are very few unallocated sources of fresh water. We are turning slowly toward “alternatives” such as municipal and industrial wastewater, saline groundwater, the sea, irrigation return flow, and produced water that comes up with oil and gas deposits from deep beneath the surface of the earth. Slowly turning, not because of a lack in technological ability, but because it takes a large capital investment to acquire and treat these sources to a level at which they can be used. The regulatory system is not geared up for alternative sources and treatment processes. Permitting can be circular, contradictory, time consuming, and very expensive. The purpose for the water, or the value of the product obtained using the water, must be such that the capital and ongoing expense seem reasonable.

There are so many technological solutions for recovering water quality that choosing the most reliable, economical, and environmentally sound technology involves unraveling the “best” weave of treatment processes from a tangled knot of alternatives. Aside from permitting issues, which are beyond the topic for this presentation, the “best” weave of processes will be composed of four strands specifically fitted to the local situation: energy, pretreatment, driving force for separation processes, and waste management.

A range of treatment technologies will be examined in this presentation with a focus on how the quality of the feed water, available power sources, materials, and waste management opportunities aid in choosing the best weave of treatment technologies, and how innovative use of a wide variety of driving forces are increasing the efficiency of treatment processes.