Thank you for the comment. One would think that what you say is true, that there would be a strong incentive to explore waste water recycle opportunities. Howevr, I don't see much evidence that industry has agressively or even non agressively, pursued opportunities to innovate here.

A key technical concern when recycling waste water is the rapid build up of salinity, removal of which becomes the limiting step. Therefore, not only does salinity ( and "t.d.s.", total dissolved solids) need to be removed, but it needs to be done with high water recovery, in order to maintain the aim of saving water. Technologies that treat t.d.s are few, and tend to be older than the alphabet. Use of any existing technologies in order to achieve high recoveries with produced water, which is likely to have compounds that would tend to foul water treatment systems, would in and of itself be an experiment.
Therefore, any technology would be a new technology when used under these conditions. Some of the older technologies, such as R.O ,have been tested to death., while promising new technologies have received insufficient or incompetent due diligence

Generally, salinity build-up only becomes a problem when one goes to very 'tight' recycle systems.

I would venture that if the tar sands process can use recycled wastewater at all, it would probably be able to tolerate at least a 75 percent recycle rate, which would reduce net water consumption by a factor of about four.

However, once one tries to tighten up the wastewater recycle much beyond that point, various problems with salinity, corrosion, scaling, bio deposits, etc. can rear their ugly head.

I think that given the critical water supply situation in the Alberta tar sands, wastewater recycle is an area well worth exploring.