October 2013, Vol. 25, No.10

Research Notes

BlueTech Research predicts increase in indirect potable reuse

Implementation of indirect potable reuse is on the rise according to a report compiled by BlueTech® Research (Vancouver, British Columbia).  

Currently, nonpotable applications account for 87% of all U.S. municipal wastewater reuse projects and the number of these projects is growing steadily, according to the report. But the market for indirect potable reuse is set to grow faster than nonpotable reuse. This can be attributed to lower marginal costs and a growing demand for potable water supplies in urban areas, the report says. 

“In general, indirect potable reuse will make more financial sense than nonpotable reuse in states such as Florida, Texas, and California. However, it remains to be seen whether the issue of public perception will allow water reuse decisions to be made purely on a financial basis,” said Conor Dennehy, research analyst at BlueTech Research. 

The development of regulations in California — the first step toward standardizing the treatment train required for indirect potable reuse — could further increase adoption of these projects and the processes associated with them. California’s Title 22 regulations require the use of reverse-osmosis treatment followed by oxidation, called Full Advanced Treatment. If other jurisdictions follow a similar approach, then demand for reverse osmosis, membrane filtration, and advanced oxidation processes will grow significantly. In addition, as one of the dominant technologies for the process, ultraviolet light disinfection will continue to grow, the report says. 

The potential growth market for indirect potable reuse is projected to increase during the next 10 years as regulation, markets, and applications open up to additional indirect potable reuse projects in municipal wastewater reuse, the report says. 


Inventor of the ultraviolet LED for water purification recognized for innovation 

Theodore Moustakas, co-inventor of the blue light-emitting diode (LED), has been recognized as Innovator of the Year by Boston University.  

As professor in the university’s College of Engineering, Moustakas has researched topics in opto-electronic materials and devices and has been granted 25 U.S. patents with several more pending in the fields of nitride semiconductors, amorphous silicon, and diamond materials, according to a university news release.  

The award recognizes entrepreneurial faculty members as well as their cutting-edge research and the potential for commercialization or wider adoption of their inventions, the news release says. 

Moustakas’ lab focused on developing semiconductors for photonics and other applications. With this technology, he founded RayVio Corp. (Boston), a venture-backed company that makes ultraviolet LEDs for water purification and disinfection. His inventions have been deployed by many LED manufacturers, the news release says.  

“His accomplishments in the past year include nine peer-reviewed papers, five patent filings, and $4 million invested in Boston University spinoff RayVio,” said Jean Morrison, Boston University provost and chief academic officer, in the release. 

In addition to his research and patents, Moustakas has been the co-editor of eight books, authored chapters in nine books and more than 300 papers, presented 116 talks at conferences, been elected as a Fellow of the American Physical Society (College Park, Md.) and Electrochemical Society (Pennington, N.J.), received an honorary degree from Aristotle University ( Thessaloniki, Greece ), received the Molecular Beam Epitaxy Innovator Award, and received the Distinguished Scholar Award from Boston University’s College of Engineering, the news release says. 

August WER focuses on struvite control effectiveness 

Struvite accumulation is a problem in many water resource recovery facilities (WRRFs) that use anaerobic digestion. It leads to significant labor and equipment costs and potentially affects facility performance and permit compliance. The August issue of Water Environment Research includes a research report detailing the process and conclusions about potential solutions. 

To evaluate the effectiveness of several control techniques, two similar Miami–Dade County, Fla., WRRFs conducted a comprehensive study using a newly constructed dynamic process model and a net present worth analysis. The facilities tested periodic cleaning and repair of damaged piping and equipment; optimum ferric salt dosing; use of in situ scaling coupons; and engineered struvite precipitation to recover nutrients. 

The study consisted of five steps. First, researchers determined the optimal ferric salt doses required to effectively control struvite at each WRRF using a newly developed ferric dosing model and laboratory testing. Second, they performed a field evaluation of applied ferric doses using scaling coupons strategically located throughout each facility. Third, they performed pilot testing of engineered struvite recovery using centrate from both facilities. Fourth, they developed a model with a struvite module to determine the effectiveness of chemical treatment and the feasibility of implementing a phosphate recovery process at the two facilities. Finally, using results from this study, along with an economic evaluation, the researchers determined the best possible approach for controlling struvite at each facility.  

The results indicate that nutrient recovery was a potential benefit at both facilities. 

In addition to finding results for these two Florida facilities, this study also establishes a comprehensive process and specific testing protocols for evaluating struvite control alternatives for others. 

The article, “A Theoretical and Practical Evaluation of Struvite Control and Recovery,” is available as an open-access document in the August issue of Water Environment Research and can be downloaded free at http://goo.gl/yhEJPg. 



Water Environment Research allows open access to one article per issue on a range of important technical topics such as nutrient removal, stormwater, and biosolids recycling