Water Workshop Program

Session I: Thursday AM

Lauren Greenlee, NIST, Boulder, CO
Chemical Engineer, Materials Reliability Division
"Measuring up to Sustainable Water: Outcomes from Sept. 2010 NIST-Virginia Tech Workshop"

This talk will give an overview of the 2010 NIST-Virginia Tech Workshop "Measuring Up to Sustainable Water", with a focus on the Membranes Track discussions and results.  Attendees at the 2010 NIST-Virginia Tech Workshop identified several key areas of need in membrane characterization, including biofouling and nanoscale morphology.  Ultimately, the structure, properties, and performance of membranes must be correlated to accurately predict membrane lifetime.

Jessica Torrey, NIST, Boulder, CO
Materials Research Engineer, Materials Reliability Division
"Nanotechnology for Water at NIST"

The heart of membrane separations is the dynamic processes that occur at surfaces and interfaces. However, despite improvements to membrane technology itself, the characterization techniques that are applied to analyze membranes are outdated and deficient. Most provide bulk, or macroscopic, measurements (e.g., flux decline) or are post-process techniques that cause changes to the membranes (e.g., electron microscopy).   This talk will describe the efforts at NIST-Materials Reliability Division to develop and apply measurement techniques for the in-situ, real-time, nanoscale characterization of next generation nanotechnology-based membrane materials in aqueous environments.

Edwin Chan, NIST, Gaithersburg, MD
Polymer Research Engineer, Polymers Division
"Measurement methods for understanding structure of model membranes for clean water"

The growing demand for clean water requires thin film composite membranes with enhanced energy efficiency for water permeation and salt rejection, thus requiring an improved understanding of the structure-performance relationships of the active polyamide (PA) layer. In an aim to establish these relationships, this talk will present an overview of the fabrication approach and measurement tools for model crosslinked PA membranes. In the first part of the talk, we will discuss a new synthetic strategy for constructing model PA membranes that overcome some of the limitations of traditional interfacial polymerization. The model membrane layer is constructed based on a molecular layer-by-layer assembly that builds the film via alternating reactions of di-amine with tri-acid chloride monomers. Additionally, we will present measurement tools for characterizing the local chemical structure of these model membranes. In the second half of the talk, we will present a wrinkling-cracking methodology that simultaneously measures the stiffness, fracture strength, and onset fracture strain of ultrathin films and supported membranes. These measurements give insight into thin-film mechanical behavior, such as 'embrittlement' upon chlorination of the PA membranes. The increased brittleness of these membranes upon continuous chlorine attack changes their fracture behavior significantly, which is linked to performance degradation.

Stephanie Hooker, NIST, Boulder, CO
Division Chief, Materials Reliability Division
"Monitoring Emerging Contaminants:  New Test Methods and Standards"

Ensuring the safety of tomorrow's drinking water will require substantial advances in monitoring and removal of organic and inorganic contaminants.  Water treatment facilities are facing an ever-increasing quantity and variety of pollutants, including industrial effluents, engineered nanoparticles, and pharmaceuticals.  Conventional water purification techniques, such as chlorination processes, are proving ineffective in treating many of these new contaminants, and can even lead to the production of more toxic by-products that further complicate water quality monitoring and treatment.  New analytical methods are being developed at NIST to detect emerging contaminants and understand their complex degradation, reactivity, and toxicity in water systems.  For inorganic nanoparticles, these methods also include measurement of particle size, shape, surface chemistry, surface charge, oxidation state, and transport properties in water.  NIST is developing reference materials for pure and contaminated water, standard protocols for sampling and testing, and new instrumentation for monitoring the evolution of these contaminants during treatment.

Session II: Thursday PM

Michelle Chapman, Bureau of Reclamation, Denver, CO
Physical Scientist, Brackish Groundwater National Desalination Research Facility
"Technology and Water"

Pundits are continually decrying the cost of advanced water treatment and calling for more and more research to develop better, cheaper, more efficient water treatment process.  Regularly there are news flashes about the "unveiling" of a new process that cuts the energy use of seawater desalination in half.  If one has the training and experience to tease out the details of such a process, one usually finds that it is breaking the laws of thermodynamics, or it is just not as revolutionary as it seems.  When will we achieve success and how will we know if we have?  The Federal Government has invested in advanced water treatment research for over fifty years.  Over this time every conceivable concept for desalting water has been explored.  New materials technology may enable the realization of some of these concepts.  When they are realized, the Brackish Groundwater National Desalination Research Facility (BrGNDRF) will be ready to prove them.  

Testing of new technology is not a trivial undertaking.  Reclamation and the BrGNDRF have been a certified as a Testing Organization under the EPA and National Sanitary Foundation International's Environmental Technology Validation program.  Our principle evaluation was for the Office of Naval Research funded Expeditionary Unit Water Purifier (2005) which remains an example of the state of the art in seawater desalination.  We have also participated in planning for testing new technology for the DARPA's (Defense Advanced Research Programs Agency) Materials with Novel Transport Properties program and the ONR's (Office of Naval Research) Expeditionary Unit Water Purifier Science and Technology program and Future Naval Capability program.  In this presentation we will share insights gained in the practice of evaluating new technology.

Alan Greenberg, University of Colorado, Boulder, CO
Professor and Associate Chair, Mechanical Engineering
Executive Director, Center for Membrane Applied Science & Technology (MAST)
"Sensor-Controlled Flow Reversal for Scaling Mitigation in Reverse Osmosis Desalination"

A major problem for RO utilization is that efficiency is compromised by the development of scaling that significantly degrades membrane performance and water quality, and hence increases desalination cost. Flow reversal (FR) enables the entry and exit points of the feed to be periodically reversed before the induction time for measurable scalant is exceeded. This presentation will discuss the use of in-situ ultrasonic sensors to optimize FR scaling mitigation.

Tzahi Cath, Colorado School of Mines, Golden, CO
Assistant Professor, Environmental Science and Engineering
Engineered Systems Leader, NSF ERC on Reinventing America's Urban Water Infrastructure
"Thermally and Osmotically Driven Membrane Separation Technologies: Membrane Limitations and Needs"

Membrane distillation and forward osmosis (and their relative processes) are two novel membrane separation technologies that have been thoroughly studied in recent years for applications in water and wastewater treatment and for desalination. These technology are able to treat several streams that commonly can not be treated by conventional membrane separation technologies such as MF, UF, NF, or RO. These advantages are confronted with a major hurdle for commercial development of the technologies - the lack of high efficiency and robust specialized membranes. Examples of process application and membrane development needs will be presented.

Session III: Friday AM

Balasingam (Verl) Murugaverl, University of Denver, Denver, CO
Lecturer/Director of undergraduate laboratories, Department of Chemistry and Biochemistry
"Better Membranes through Structure Property Relationship"

The lack of understanding of the structure property relationship is the major obstacle in developing advanced application specific membranes.  This is especially true in membranes where interfacial polymerization is used, like in RO and nanofiltration membranes.  The chemical properties of the membrane can be controlled through the chemical structure, while the transport properties seem to depend mainly on the conditions employed in the interfacial polymerization step.  There is very little understanding of the correlation between the polymerization conditions and the performance of the membrane.  A better understanding of this relationship will allow custom tuning the membrane for intended application.  We will look at a systematic study aimed at fine tuning the chemical and physical properties of RO membranes.

Ken Clark, City of Boulder Public Works, Boulder, CO
Regulatory Compliance Specialist; Water Quality and Environmental Services
"Nanotechnology and Nanomaterials in Drinking Water: Issues, Opportunities and Challenges"

In many important respects nanotechnology and nanomaterials are still so new to water utilities that we are not yet sure even how to define or characterize them. This technology often seems to be advancing faster than our ability to describe it, much less to contemplate the full range of potentialities and socioeconomic implications. For utilities our ability to retain the confidence of our customers in our product depends significantly on our capacity to evaluate and communicate clearly the costs, benefits and risks of any treatment technology. Utilities need to define and articulate their treatment and delivery technology needs and work closely with researchers and industry to develop and implement them. Successful adoption of nanotechnology by the drinking water industry will involve expressing confidently our treatment and resource management decisions so that we not only improve public and environmental health but enhance our customers' trust.

Oleg Polyakov, Synkera Technologies, Inc., Longmont, CO
Senior Scientist
"New Ceramic Ultrafiltration Membranes with Monodispersed Pores"

Membrane-based processes, from reverse osmosis to microfiltration, are often considered a preferred (less-costly and high-throughput) option in separating components in complex mixtures, including water purification. Using self-organized anodic aluminum oxide as a material platform, Synkera has developed new nanostructured ceramic membranes for, primarily, ultrafiltration of liquids. These membranes feature unique asymmetric architecture comprising (i) relatively thick (50-100 µm) support layer with large-diameter (>80 nm) pores and (ii) thin sub-µm active layer with monodisperse nanometer-scale pores. Novel fabrication methods employed allow convenient control of the pore diameter to any desired value in the 0.5 - 20 nm range – previously inaccessible with anodic alumina technology – with great precision. High pore density, thin active layer and large-diameter pores in the support layer enable high fluid permeance. As a result, membranes exhibit unprecedented sharp and controllable (in the range of below 5 to over 300 kDa) molecular weight cut-off and high flux. Case studies for membrane-based fractioning of proteins and water-soluble polymers have been performed.

Session IV: Friday PM

Gautam Khanna, Tusaar, Inc., Boulder, CO
Founder and CEO
"Green Technology for the Removal of Heavy Metals from Water"

Heavy metals, often toxic, are found in various streams like acid mine drainage, mining waste streams, industrial process and discharge streams. Very rarely, if ever, is it that metals are the only pollutants. Metals are normally found in an acidic environment along with a host of different pollutants including but not limited to organics, multiple acids and anions. While these individual pollutants can be managed separately the combination presents a tough challenge. Acids can be neutralized and anions managed but the interaction of metals with organics presents a unique challenge. Tusaar is working on a novel technology that is effective in the presence of varying other pollutants, is robust enough to handle a varying environment in pH and hardness and has the ability to sequester more than 40 different metals. The technology reduces waste, enables the regeneration of acids if needed, permits the recovery of metals and is easy to use.   Tusaar has licensed this technology from CU Boulder and is funded by US DOE. It uses commonly found, environmentally friendly sorbents and chemicals to develop this media and is looking forward to growing its base of customers in the Front Range.

Keith Miller, University of Denver, Denver, CO
Associate Professor, Department of Chemistry and Biochemistry
"Wastewater treatment by wet air oxidation: an overview of laboratory studies using a vertical tube reactor (VTR) design"

Municipal sewage and agricultural wastewater treatment and disposal remain a public concern as populations increase and wastewater treatment infrastructures age.  In addition, many pharmaceuticals [and other potential endocrine disrupting compounds] are not removed completely by current wastewater treatment technologies.   Thus, treatment technologies are being evaluated that remove these so called "emerging contaminants" from wastewater effluent.  We present a lab-scale demonstration of the removal of antibiotics from surrogate and wastewater effluents using a wet air oxidation technique.  The laboratory reactor serves as a model for a full scale vertical tube reactor (VTR) that was successfully demonstrated at a wastewater treatment plant.  We demonstrate the effectiveness of the wet air oxidation process by removing a series antibiotics (sulfonamides, tetracyclines and lincomycin) and a model polycyclic aromatic hydrocarbon (PAH) with greater than 93% efficiency from high organic matter solutions and spiked wastewater effluent (prior to disinfection).   In addition, field studies are shown that demonstrate the effective treatment of wastewater from lagoons from hog farms. Temperature, residence time in the laboratory reactor, and effluent pH conditions are evaluated to aid in the design of full-scale systems. We conclude with preliminary results from the treatment of other surrogate waste streams that represent those found in the energy sector. (co-author with Jay McGrew of Applied Science and Engineering)

Hsiao-wen Chen, Water Research Foundation, Denver, CO
Research Manager
"Challenges with Membranes for Water Treatment"

Fouling of membranes remains a significant technical challenge to drinking water utilities. This presentation will summarize the latest Water Research Foundation's research on this topic.

Ron Falco, Colorado Safe Drinking Water Program, Denver, CO
"EPA Regulations and Implementing Current Drinking Water Requirements"

This presentation discusses potential upcoming EPA regulations. Specifically, upcoming new contaminants may be regulated and the total coliform rule is going to be revised. Additionally, implementation of recently adopted rules and state approval of new technologies will be addressed.