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Wastewater resource recovery has been advocated for decades; necessary structural pathways were long-ago articulated, and established and emerging technologies exist. Nevertheless, broad wastewater valorization remains elusive. In considering implementation barriers, the argument is made that decision-makers focus on avoiding permit violations and negative publicity by embracing a conservative/safe approach--seemingly ignoring research on economic/environmental benefits. Conversely positing that economics is a primary barrier, we investigated, characterized, and described nontechnical socio-political barriers to realizing wastewater resource recovery. Principal actors in the Pacific NW region of the U.S. (representing a progressive populace facing stringent water quality regulations) were interviewed. Results revealed that economics were, indeed, the primary barrier to implementation/expansion of the WRRF concept. Consistent throughout interviews was a prevalent sense that the "cost of doing something (different)" was a principal consideration in resource recovery actions/policies. Moreover, "economics drives decisions," and "95% the bottom line is money. Show return on investment, it will get people's attention." Who pays was also a concern: "Government isn't going to pay. The states and Federal government won't give any grants, and we can't raise rates." Applying business case evaluations was seen as a pathway to actualizing resource recovery. Most encouragingly, the consensus was that resource recovery is a necessary future paradigm, and that real barriers are surmountable. [ABSTRACT FROM AUTHOR]

BACKGROUND: In 2012, 9.3 million head of dairy cows in the USA produced an estimated 20 million metric tons of manure solids, but little value was gained from this manure. There is a pressing need to enhance manure resource recovery efforts, as dairy manure has potentially significant environmental impacts. This study evaluated components of an integrated suite of biological processes designed to maximize resource recovery from dairy manure, in which algae grown on polyhydroxyalkanoate (PHA) production effluent (PHA-algae) were fermented and anaerobically digested to determine process impacts. RESULTS: A 10% PHA-algae supplement produced 11% more volatile fatty acids (VFA) during fermentation and 11% more methane during anaerobic digestion (AD) (vs. dairy manure); the PHA-algae biogas also contained a higher percentage (62.7 vs. 59.1%) of methane than manure biogas. Algal augmentation exhibited no negative effect on fermenter or AD operation. Quantitative polymerase chain reaction (PCR) showed that the ADs contained substantial populations of both acetoclastic and hydrogenotrophic methanogens, which, given the heterogeneous substrate, enhanced process stability. There were significant differences between PHA-algae batches, and large quantities of COD were released during algae freezing. CONCLUSION: PHA-algae yielded more VFA during fermentation, and a more methane-rich biogas following AD than dairy manure. A 10% PHA-algae supplement caused no process disturbance in normal manure flora. [ABSTRACT FROM AUTHOR]