Table 8 - uploaded by Victor F. Medina
Content may be subject to copyright.
Source publication
A new water treatment system is planned for Fort Irwin in Barstow,
California to address existing regulatory requirements and to account for
anticipated expansion at the installation. Fort Irwin has indicated a water
recovery requirement of 99%. Achieving this level will require a treatment
system for the electrodialysis reversal (EDR) reject strea...
Context in source publication
Context 1
... flux increased, treatment generally improved, and at flux levels greater than 8 gfd, fluoride levels in the permeate were less than 2 mg/L (Figure 18). Table 8 shows water chemistry of two flux rates close to 10 gfd with water recoveries of 53 and 56%. Fluoride ranged from 1.65 to 1.90 mg/L, which was below the MCL of 2 mg/L. ...
Citations
... The media filter processes are designed to be a pretreatment, removing constituents that could compromise the polishing and final processes, which is a six stage reverse osmosis system. The reverse osmosis (RO) system provides high rejection of organic and inorganic contaminants ( Medina et al. 2012;Medina et al. 2015), including chemical warfare agents and radioisotopes. Detailed information on the DETS is provided in three previous publications (Dedeaux and Medina 2017;Medina et al. 2018aMedina et al. , 2018b; Medina 2019). . ...
A previous ERDC report described the effectiveness of the Decontamination Effluent Treatment System (DETS) for the treatment of wash water generated from simulated CBRN decontamination. This study compliments that previous one in that it focused on the treatment of a simulant from Mass Personnel Decontamination (MPD). Treatment of both cesium 133 (used as a surrogate for radioactive cesium 137) and Malathion (as a surrogate for organophosphate chemical warfare agent) equaled or exceeded 99.95%. The conclusion was that the system proved to be highly effective at treating wash water from MPD, which would allow discharge or even potential reuse for more decontamination. The ERDC team conducted studies that confirmed that the DETS could be integrated into CERFP activities with minimal disruption. In addition, the DETS underwent a long road test in which it was driven for over 1000 miles from Vicksburg MS to St Robert MO (Fort Leonard Wood) and back. The conclusion is that the DETS could be moved around the United States as needed to respond to decontamination events. The DETS was also used to treat PFOS, a perfluorinated compound found in legacy firefighting foams, and the DETS processes achieved 99.97% removal of ~30 µg/L PFOS. DISCLAIMER: The contents of this report are not to be used for advertising, publication, or promotional purposes. Citation of trade names does not constitute an official endorsement or approval of the use of such commercial products. All product names and trademarks cited are the property of their respective owners. The findings of this report are not to be construed as an official Department of the Army position unless so designated by other authorized documents.
... Follow-on flux experiments were conducted at the 413.4. Two conventional membranes were evaluated at this pressure for comparison purposes: (1) a RO membrane [General Electric (GE), Sterlington, Louisiana, polyamide AD membrane, a high-rejection membrane], which had been previously studied for treatment of groundwater (Medina et al. 2012(Medina et al. , 2015; and (2) a nanofiltration (NF) membrane (GE Osmonics, TF polymer). The NF membrane was previously shown to reject methylene blue and exhibited a molecular weight cutoff range of 150-300 Da. ...
Graphene oxide (GO) has emerged as a promising material for next-generation water treatment membranes. In this study, three types of GO membranes were produced and tested. Both GO and graphene oxide plus polyvinyl alcohol (GO/PVA) membranes were produced using the vacuum-assisted self-assembly (VASA) method, and a chitosan and graphene oxide composite membrane (CSGO) was assembled using GO as a nanoscale filler via evaporation under reduced pressure. Scanning electron micrographs (SEMs) confirmed that GO and GO/PVA membranes were particularly well ordered, whereas CSGO exhibited reduced ordering attributed to structural and composition differences of GO and CS. The fabricated membranes were tested in a dead-end flow system indicating that each membrane containing GO produced a higher flux at 413 kPa pressure relative to conventional polyamide reverse osmosis (RO) membranes used for benchmark comparison, but was lower in flux to a nanofiltration (NF) membrane. Challenging the membranes with 7.5 mg=L methylene blue solution resulted in ≥ 97.5% removal of the dye by all three of the membranes.
... For example, at Fort Irwin, a new water treatment plant treating groundwater has a target water recovery goal of 99%, which is higher than other published systems. To reach this high level, a portion of the water will be treated by mechanical vapor recompression, a distillation process that is relatively expensive (Medina et al., 2012). Detecting and repairing leaks can result in reductions in water use, energy demand, and the consumption of water treatment chemicals. ...
Reducing water loss at U.S. Department of Defense (DoD) installations is important to preserve potable water needed for essential functions and to limit the drawdown of local water supplies. Implementation of improved leak detection technologies and the timely repair of water mains will support Federal and DoD sustainability goals. This project assessed three innovative acoustic leak detection technologies with enhanced cross-correlation features to detect and pinpoint leaks in challenging pipe types, as well as metallic pipes.
... For example, at Fort Irwin, a new water treatment plant treating groundwater has a target water recovery goal of 99%, which is significantly higher than what other systems require. To reach this high level, a portion of the water will be treated by mechanical vapor recompression, a distillation process that is relatively expensive (Medina et al., 2012). Detecting and repairing leaks can result in reductions in the energy demand, the amount of chemicals used for water treatment, and the amount of water being treated and distributed, which ultimately lead to additional cost savings. ...
Many potable water distribution systems at Military installations were installed prior to 1970 and are reaching the end of their design life (i.e., 50 to 75 years). These systems have typically been built up incrementally using a wide mixture of pipe sizes and materials, with ductile or cast iron, asbestos cement (AC), steel, and polyvinyl chloride (PVC) being the most widely used. Leaks are commonplace in older distribution systems and the majority of leaks are not typically noticed until water rises to the surface. Small leaks even at one gallon per minute (gpm) can result in the loss of over 500,000 gallons per year from the system. Although there are approaches that use acoustic technologies to locate leaks, many lack a cross-correlating feature for pinpointing leaks in various pipe types. This paper will discuss a recent demonstration and evaluation project of innovative acoustic technologies that have the potential to overcome the challenges with traditional leak detection tools used in challenging pipe type systems prevalent at Military installations. This project is expected to enhance the Military's knowledge base for locating leaks in both metallic and non-metallic pipe types.
The United States Army is constructing a new water-treatment facility for Fort Irwin/National Training Center in the Mojave Desert region of southern California to address existing regulatory requirements and to account for anticipated expansion at the installation. The proposed treatment, electrodialysis reversal (EDR), is anticipated to recover 92% of the influent water. The ultimate goal was to achieve 99% recovery, which required additional recovery of the EDR concentrate. This paper describes laboratory testing of conventional water-treatment methods to achieve water recovery beyond standard practice. The effectiveness of lime softening followed by secondary reverse osmosis (RO) was evaluated to treat the concentrate stream and recover additional water to approach 98%. Partial lime softening at dosages of 500 − 2,000 mg=L of hydrated lime was capable of removing hardness from simulated EDR concentrate. Adding magnesium chloride to the lime softening step increased silica removal, bringing SiO 2 concentrations in the simulated EDR concentrate from 110 to 6.8 mg=L at room temperature. The resulting treated water was suitable for effective reverse osmosis with a standard seawater polyamide membrane. Rejection for all of the dissolved constituents was well above 90% with the exception of arsenic, which was reduced from 50 μg=L to levels on the order of 20 μg=L. To achieve 99% recovery, mechanical vapor recompression is being considered to further recover the concentrate from the RO unit, although this unit process was not evaluated in the research reported in this paper.
