Lab Partnering Service Discovery
Use the LPS faceted search filters, or search by keywords, to narrow your results.
An environmental engineer at the Savannah River Site has developed a software application that will determine if non-aqueous phase liquid (NAPL) contaminants are present in soil, groundwater, or soil vapor samples. The software will determine both the quantity and composition of NAPL chemicals in the samples based on the results of sample analysis. The software also computes important environmental engineering measures such as the residual saturation, mass of the NAPL in the sample, and mass balance and phase distribution of each chemical composing the NAPL.
NAPL is an especially detrimental type of environmental contaminant. It exists in soil or groundwater as the same organic chemical(s) originally shipped from the manufacturer. Often NAPL comprises different chemicals like trichloroethylene (a solvent) or polychlorinated biphenols (a liquid electrical insulator). It is extremely difficult to detect in the environment; sometimes its presence must be determined by inferential evidence rather than by direct measurement.
Failure to recognize the presence of NAPL at a waste site will almost certainly result in failure of clean-up efforts. It is long lived, has low solubility, and is resistant to many conventional remedial technologies. Most importantly it will provide a reservoir of contamination for both soil and groundwater on a time scale of 10s to 100s of years. Therefore, it is absolutely essential that environmental engineers have a tool they can use to assess the nature and severity of NAPL contamination in order to apply and design the correct clean-up technology.
The NAPL Calculator is an analytical model that is a self-executing Microsoft Excel workbook that requires qualitative/quantitative soil, groundwater, or soil vapor sample results and a few simple geotechnical parameters. A classic chemistry approach is used that is based on the work of Shiu, Feenstra, McKay and Cherry and is advocated by the U.S. Environmental Protection Agency.
The method is known to many academics and researchers but not to many practitioners in environmental clean-up. Even for those who know the method, the calculation can be laborious. The NAPL Calculator is designed to make this calculation method accessible, understandable and self-explanatory.
The user selects the chemical(s) detected in the analyses from a pull-down menu, enters the concentrations for those chemicals, and provides some information about soil porosity. The software contains an imbedded database of physical chemical parameters that it uses to generate a robust body of information that can be used by environmental engineers to assess the level of contamination at a waste site.
Some of the information the software provides is:
1. The existence of NAPL in the samples
2. The total mass of NAPL in the samples
3. The total mass of NAPL for each chemical composing the NAPL
4. The volume of NAPL in the samples (called the residual saturation)
5. The concentration and mass of each chemical
6. The vapor pressure of the NAPL and of each chemical
7. The solubility of the NAPL and of each chemical
8. A mass balance and volumetric balance for each chemical
9. The percent composition of each chemical
10. Automatic graphing of some of the above information
The GrayQbTM is a device with accessories, to locate, identify, and generate a map of radioactive contamination within an enclosed area. It is a cubic device that utilizes multiple layers of Phosphor Storage Plates (PSPs) that are highly sensitive which translates into shorter counting times. Even with low dose rate environments, this device can be used to expedite radioactive contamination cleanup operations. The PSPs from GrayQbTM device are read on a commercially available scanner where special software records and translates the exposure data to define the type and location of the radioactive source(s).
The PSPs used for GrayQbTM are commonly used for imaging purposes where the radiation source and dose rate are known. This device was developed with the goal of "minimal dose" in mind. The result is a high resolution, high sensitivity gamma detector material capable of micrometer resolution and mR levels of dose required. In order to provide energy determination and identification of a radioactive source and its intensity, the PSPs are stacked into a sandwich, separated by attenuation material such as metal, plastic, etc. An unknow radiation source will deposit the most dose to the outer-most PSP, with each successive layer beneath receiving less than the previous one. Based on the amount of exposure to eacy layer, the energy of the incident radiation can be determined. Modified configurations using other film types can be used for alpha, beta, or neutron detection.
GrayQbTM is placed in a confined are for a predetermined span of time based on expected dose rates. A set of motorized shutters shield the PSPs during placement and removal of the device. Once in position, the attenuated PSP layers are exposed to the sources in the area through a unique collimation apparatus. It is then removed from the area where the PSPs are read in an optical scanner. Using special software, the data from the PSPs is translated into a map of the locations, intensities, and energies of the source contamination.
SPR is an optical phenomenon that enables detection of molecules adhering to a surface. SPR is often detected as a loss in reflected light intensity at a specific frequency or wavelength of light as the incident light energy is coupled into the surface plasmon wave. The wavelength dependence of this intensity loss is analyzed and can be used to quantitatively determine the molecular adsorption on the surface of the SPR active material. Most SPR experiments are performed using expensive benchtop instruments wth bulky optical components, making SPR difficult to employ in remote sensing applications.
The SPR sensor enables remote measurements in a stable, robust probe format, consisting of a commercially available attenuated total reflection (ATR) probe modified to support SPR. Thin layers of gold and silica are deposited on the curved apex of the ATR hemispherical lens. This modified probe allows for sensitive detection of gas molecules as they adsorb onto the silica surface.
The use of the hemispherical ATR probe as the starting optics allows for the sensor to be placed at the end of a fiber optic cable that carries both the incident light and the reflected signal back to the measuring instrument. The curvature of the hemisphere compensates for the divergence of the source fiber and refocuses the light back to a collection fiber. This fiber optic SPR probe has been show to produce extremely high resolution, low noise SPR spectra typical of expensive benchtop systems.
The SPR sensor probe is extremely sensitive to water vapor adsorption onto the probe surface. It has been applied to atmospheric moisture monitoring and has shown sub-ppm sensitivity over a range of ~0 to 100% relative humidity (0.750 to >20,000 ppm at 25°C, 1 atm). Although the current probe is configured as a moisture sensor, the technology, using different materials, is applicable to measurement of any gas phase species that can condense on the probe tip from some equilibrium concentration in the gas phase. The probe is especially useful in an environment where an electrical measurement is undesirable, or where there is electrical noise interference. In an alternate configuration, the SPR sensor can be used to make highly accurate measurements of the refractive index of a liquid.
The Pneumatic Conveyance Device is capable of dislodging, capturing, and conveying solid material, wet or dry, from a depth of 70+ feet, while discharging through a 100+ foot conveyance hose. The device was developed to remove water and solid material from the annular space between the tank and line of a buried, double-hulled tank. The device relies on pneumatic “push” technology rather than the “suction” technology that has been traditionally used in pneumatic conveyance devices.
While suction devices create high vacuum at the expense of high air consumption, this device utilizes a different design which creates a significantly stronger “push” on material and better material conveyance (at the expense of reduced suction). The advantage of this device over similar suction devices is they are limited to 25 feet.
The primary component of the system is a pneumatic conveyance nozzle. The system was tested and successfully removed a mixture of sand, rock, wet sand, and water from a barrel to a collection tank elevated 70 feet above the barrel. Additionally, the system was attached to a scarifying tool, and performance tests were conducted on a cured mixture of plaster, sand, and aggregate, to simulate the hardest, anticipated material that might be encountered. The suction port of the nozzle was blocked sporadically, but a port valve at the discharge end of the conveyance hose can reverse the flow temporarily to free the blockage.
Engineers at the Savannah River National Laboratory (SRNL) have developed a remotely-operated tank cleaning device for precise, high-pressure spray for use in limited access areas. The device offers features unavailable in tank cleaning technologies currently on the market, providing for better, faster and cost-effective tank cleaning.
The directed spray mast was originally conceived to eliminate the inherent dangers involved with sending workers into storage or process tanks during cleaning operations. The directed spray mast was designed to provide more precise cleaning of problem build-up areas within a tank versus the more global cleaning approach of existing technologies.
The design features of the directed spray mast provides for effective cleaning up to 20 feet away from the access point at pressures as high as 3,000 psi. Tank entry for the directed spray mast requires an access port of only three inches in diameter. In addition, this spray device has been effective in cleaning either hard or soft sludge buildup while requiring less water and electricity to accomplish the task.
The Orangutanktm is a remote controlled, tethered robotic platform for traveling from one pipe to another using a network of vertical pipes for support.
The Orangutanktm combines specialized robotic grippers to provide gripping and rotational capability to maneuver from pipe-to-pipe without ever having to descend to the floor. The extending and retracting arms allow for reaching between the vertical pipes, maintaining a constant grip by one arm while swinging into position for a stronghold by the other arm. The flexible and extendable arms of the Orangutanktm allow for variances in pipe spacing and configurations.
No other robotic platform can negotiate vertical pipe forests to achieve the desired travel of this device. It is designed to allow it to "swing" from one pipe to another similar to its namesake, the orangutan who swings from tree linb to tree limb in order to navigate the forest.
(Short video clip available for viewing on Savannah River National Laboratory Tech Transfer Website)
Savannah River National Laboratory has developed a replaceable coupon that provides both high resolution ultrasonic thickness (UT) and mass loss measurements of erosion and corrosion in critical locations throughout a process system without disrupting the process flow stream.
Incorporating mass loss as well as high-resolution UT measurement capability in a single device provides more sensitive measures of wear than conventional systems or systems providing highresolution UT measurements alone. In addition, the unique size and design allow installation in vulnerable locations in a process system to provide timely information about the condition of the actively operating system. Because it can be used in an actively operating system, this device can dramatically reduce large-scale testing costs.
The coupon can provide in situ high-resolution UT measurements in most locations (piping, tanks, ducts, injection points, etc.) in a process system, including those with different pipe sizes/wall thicknesses. The design is optimized to allow accurate placement of a high-resolution UT pencil probe, which provides repeatable and more precise real-time wear data. This innovative design provides a means to evaluate critical evidence of corrosion and erosion without significantly disrupting the process flow stream.
The coupon can also be removed periodically to nondestructively evaluate mass loss as well as surface features resulting from corrosion (general and localized) and erosion. Once the coupon is removed, mass loss can be verified by independent techniques, such as ultrasonic and conventional micrometer measurement. An optical microscope or scanning electron microscope can be used to investigate active corrosion mechanisms, such as pitting and crevice corrosion. Finally, scar depth and orientation can be accurately evaluated using a surface profilometer or a laser confocal microscope.
Savannah River National Laboratory has developed a system for detecting water trees before they cause underground electrical cables to fail.
SRNL’s system includes a pulse generator configured to inject a pulse into a first underground cable that branches into a second underground cable and a third underground cable. The system includes a first sensor associated with the first cable, a second sensor associated with the second cable, and a third sensor associated with the third cable. The system includes a control device configured to obtain a first, second, and third signal associated with the first, second and third sensors, respectively. The control device determines a lead-lag relationship between the second and third signals and determines presence of any water tree within at least one of the second and third cables based on the lead-lag relationship. When presence of a water tree is determined, the control device generates a control action associated with repairing or replacing the second and/or third cable.
ALPES is a device that uses electrostatic precipitation to collect and concentrate airborne agents in a liquid sample for onsite or laboratory analysis. The collection efficiency is 85% to 92% depending on the size of the particles. The Aerosol-to-Liquid Particle Extraction System (ALPES) is designed to collect chemical agents; radioactive particles; microoganisms such as spores, bacteria, and fungi and molecules and other substances associated with explosives.
Agents that could be used in chemical and biological warfare tend to disperse widely in the air when released. Quickly collecting a concentrated sample of these agents is critical to detecting them before they reach harmful dose levels in the air. Also, methods of detection such as by polymerase chain reaction are enhanced when the collected agents remain alive.
Other collection devices using wet cyclone designs are larger and heavier, have higher power demands, and are noisy, thereby precluding unobtrusive uses. Devices using impactors for collection do not maintain the viability of live agents.
The ALPES takes advantage of the long-proven use of wet electrostatic precipitation to separate particles from air. The device comprises an ionization section atop a tubular collection electrode enclosed in a column. A pump pulls air throught the vertical column at a flow rate of up to 300 liters a minute.
A reservoir at the bottom of the column contains liquid that is pumped up through the inside of the collection tube, which is charged at 8,000 volts. The liquid flows over the top of the charged tube and down the sides, collecting the ionized particles from the outside surface of the tube. The flow rate maintains a continuous film of liquid on the outer surface of the tube. Constant recirculation of the liquid through the tube concentrates the collected particles.
A valved sample loop enables diversion of the liquid to an online analyzer or to a sample vial for transport to a laboratory for analysis. With minimial pressure drop, the device consumes less than 12 watts of power and operates quietly.
The recirculating liquid can be customized for specific situations. A buffered saline solution or a nutrient solution will maintain biological agents in a viable state, enabling faster and more accurate analysis.
Scientists at the Savannah River National Laboratory have developed a platinum(Pt)catalyst material that exhibits higher dispersion qualities than catalysts used in commercial fuel cells. Better dispersion translates into improved activity indicating new active sites and/or reducing the precious metal usage. Fuel cell electrocatalysts frequently employ 20-50 wt% platinum while less than 0.5 wt% Pt is needed when 100% dispersed. If every platinum atom is active for catalytic reaction rather than stacked over each other catalyst activity would increase while reducing precious metal usage. SRNL scientists have developed the method for full dispersion of active metals into a high surface area of support to promote efficiency.
A metal dispersion of 1.00 is defined as that 100% of the metal atoms are available for catalysis. Values less than 1.00 may indicate crystallite growth or a surface interference. Even as small as 3 to 4 nm particles, only 25-35% of the Pt is active in catalysis, since only that fraction of the Pt atoms is accessible. The recent development of highly dispersed metal catalyst at the atomic level has demonstrated the achievement of 100% platimum dispersion on carbon-based support and verified the catalyst activity for quantitative conversion of hydrogen and oxygen into water at ambient condition. Further, the catalyst is more active than the availability of Pt, increasing the catalyst activity by magnitudes, or reducign the precious metal usage by the same factor. The highly dispersed platinum catalyst was robust under repeated service and high temperature cycles.
A scientist at the Savannah River National Laboratory has developed a new method to separate lignin from ammonia solutions. Bio-ethanol plants typically use ammonia to separate lignin from the cellulosic fibers for a more efficient operation. Lignin itself is a byproduct with a variety of potential markets. The new method provides an efficient means of separating lignin from the ammonia to provide a product free of impurities.
Biorefineries that convert cellulosic materials to ethanol require the separation of lignin from the feedstock. The use of ammonia to separate lignin results in a by product where existing methods cannot effectively yield a pure lignin material. Existing methods typically generate an undesirable colloidal suspension that results in inefficient yields. The new method, accomplished by evaporation and pH adjustment, results in lignin that can be effectively filtered and dried free of impurities.
Biorefineries receive massive amounts of lignin from the cellulosic fibers to be processed. Lignin is an amorphous polymer that can be used as a fuel source as well as a component in the manufacture of complex polymers. The challenge has been to find a way to effectively separate lignin from ammonia free of impurities. The new method has been tested using switchgrass with other cellulosic materials currently being studied.
Scientists at the Savannah River National Laboratory's (SRNL) Hydrogen Research Center have developed new processes to add metal hydrides to nanocarbon structures to yield high capacity hydrogen storage materials. Testing of these materials has shown that hyrdogen can be efficiently absorbed and released in multiple cycles and in significant quantities. Processes to add Lithium Hydride to Fullerenes have resulted in structures that can retain and release significant quantities of hydrogen at lower temperatures and pressure.
Hydrofullerenes (C60H60) are theoretical capacity of 7.7 weight percent Hydrogen. Previous attempts to load hydrogen to a fullerene structure have been at 6 weight percent. A disadvantage to hydrofullerenes is that requires temperatures in excess of 500 degrees Celsius to desorb the hydrogen with damage to the fullerene structure. Scientists at SRNL have developed new processes using metal hydrides to develop materials where the hydrogen can be absorbed and released with greater efficiency.