Browsing by Subject "desalination"

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Center for Research in Water Resources, The University of Texas at Austin. Proceedings, Symposium on Water Production Engineering in Texas.
(University of Texas at Austin, 1966-05-03) Gage, Stephen J.; Kowarski, Lew; Strobel, Joseph J.; Holloway, Harold D.; McKee, Herbert; Wohlschlag, Donald; Fruh, E. Gus; Scanlan, J.A.; Stockton, John R.; Anderson, John E.; McIlhenny, W.F.; Walton, B.N.; Watt, John R.; Spiewak, Irving; Drew, H.R.
Desalination and long-haul water transfer as a water supply for Dallas, Texas: A case study of the energy-water nexus in Texas
(Texas Water Journal, 2010-09) Stillwell, Ashlynn S.; King, Carey W.; Webber, Michael E.; Stillwell, Ashlynn S.; King, Carey W.; Webber, Michael E.
As existing water supplies become increasingly strained in some locations, water planners turn to alternative options to quench cities’ thirst. Among these options for inland cities is desalination of seawater or brackish groundwater with long-haul water transfer. Desalination using reverse osmosis membranes is the most common technology in use, yet high pressures required for operation make desalination an energy-intensive water supply option. The subsequent conveyance of desalinated water through long-haul pipelines also requires large amounts of energy. To analyze desalination and long-haul transfer as a drinking water supply, Dallas, Texas, was chosen as a test-bed with two scenarios: seawater desalination near Houston and brackish groundwater desalination near Abilene, both with long-haul transfer of desalinated water to Dallas. Combining the energy requirements for long-distance pumping with the energy demands for desalination, we estimate that desalination and long-haul transfer is nine to 23 times more energy-intensive per unit of water than conventional treatment of local surface water sources, an increase of 230 to 630 MWh/d for 20 million gal (75,700 m3). These results suggest that desalination and long-haul transfer as a water supply for Dallas is less sustainable, based on energy consumption, than use of local surface water sources or water conservation.
Edwards Aquifer and Desalination
(The Center for Global Energy, International Arbitration, and Environmental Law, 2013-09-16) Brown, Jeremy
The Energy-Water Nexus: An Analysis and Comparison of Various Conjurations Integrating Desalination with Renewable Power
(MDPI, 2015-04) Gold, Gary M.; Webber, Michael E.
This investigation studies desalination powered by wind and solar energy, including a study of a configuration using PVT solar panels. First, a water treatment was developed to estimate the power requirement for brackish groundwater reverse-osmosis (BWRO) desalination. Next, an energy model was designed to (1) size a wind farm based on this power requirement and (2) size a solar farm to preheat water before reverse osmosis treatment. Finally, an integrated model was developed that combines results from the water treatment and energy models. The integrated model optimizes performances of the proposed facility to maximize daily operational profits. Results indicate that integrated facility can reduce grid-purchased electricity costs by 88% during summer months and 89% during winter when compared to a stand-alone desalination plant. Additionally, the model suggests that the integrated configuration can generate $574 during summer and $252 during winter from sales of wind- and solar-generated electricity to supplement revenue from water production. These results indicate that an integrated facility combining desalination, wind power, and solar power can potentially reduce reliance on grid-purchased electricity and advance the use of renewable power.
Implementation of Brackish Groundwater Desalination Using Wind-Generated Electricity: A Case Study of the Energy-Water Nexus in Texas
(Sustainability, 2014-02-10) Clayton, Mary E.; Stillwell, Ashlynn S.; Webber, Michael E.; Clayton, Mary E.; Webber, Michael E.
Growing populations and periodic drought conditions have exacerbated water stress in many areas worldwide. In response, some municipalities have considered desalination of saline water as a freshwater supply. Unfortunately, desalination requires a sizeable energy investment. However, renewable energy technologies can be paired with desalination to mitigate concern over the environmental impacts of increased energy use. At the same time, desalination can be operated in an intermittent way to match the variable availability of renewable resources. Integrating wind power and brackish groundwater desalination generates a high-value product (drinking water) from low-value resources (saline water and wind power without storage). This paper presents a geographically-resolved performance and economic method that estimates the energy requirements and profitability of an integrated wind-powered reverse osmosis facility treating brackish groundwater. It is based on a model that incorporates prevailing natural and market conditions such as average wind speeds, total dissolved solids content, brackish well depth, desalination treatment capacity, capital and operation costs of wind and desalination facilities, brine disposal costs, and electricity and water prices into its calculation. The model is illustrated using conditions in Texas (where there are counties with significant co-location of wind and brackish water resources). Results from this case study indicate that integrating wind turbines and brackish water reverse osmosis (BWRO) systems is economically favorable in a few municipal locations in West Texas
Self Sealing Evaporation Ponds for Desalination Facilites in Texas
(2007) Nicot, Jean-Philippe
The State of Texas has taken a renewed interest in desalination of brackish water. Because the Texas population is expected to grow tremendously in coming decades, many municipalities and other water-supplying entities will need to supplement their current freshwater sources. Desalination of brackish water is high on the list of water-source alternatives for supplying some or all of the increased water needs in many communities. However, disposal of desalination concentrates may pose legal, technical, and economic barriers, especially for smaller communities with water supplies of less than one million gallons per day (MGD). In this report, we examine evaporation ponds and the possibility of incorporating a low-permeability layer (precipitant) into the pond-liner system as a liner component or possibly as the liner itself. One aspect of this analysis was to investigate the regulatory requirements and barriers of using self-sealing ponds, if this strategy proves to be a technically viable alternative to standard pond liners. Another part of the work consisted of understanding the favorable chemical conditions, natural or induced, for the precipitation of such a compound(s). The third and last facet of this work was to investigate the savings or extra costs of this approach. The following observations characterize the regulatory issues relating to self-sealing pond liners. (1) No significant regulatory barriers currently exist that would prevent the permitting of self-sealing evaporation pond-liner technologies at desalination facilities in Texas. (2) No Federal authorizations are required, but a Texas Land Application Permit (TLAP) must be obtained from the Texas Commission on Environmental Quality (TCEQ) Water Quality Division. (3) TCEQ has considerable latitude for approving alternative permit requirements for industrial permits. Rules for municipal wastewater treatment are used as guides for the evaluation of industrial evaporation ponds but do not impose strict regulatory requirements. Currently approved pond liners include a 3-foot-thick layer of in-situ clay or compacted clay (with a maximum hydraulic conductivity of 10-7 cm/s) or a geomembrane liner (polyvinyl chloride [PVC], high-density polyethylene [HDPE], butyl rubber, polypropylene, etc.) of 30 mils (0.76 mm) or more with leak detection monitoring. An alternative liner technology may be approved by TCEQ if it can be demonstrated to achieve and maintain equivalent containment capabilities to the pre-approved liners and that the resulting liner material(s) will not deteriorate because of reactivity with salinity or other compounds in the effluent stream or other ambient conditions. Supporting demonstration information may include previous research, pilot projects, and monitoring data from existing operational facilities currently utilizing the proposed technology. Regulatory processing for the permitting of an evaporation pond could be simplified if the self-sealing technology were recognized by the TCEQ as an accepted type of liner, equivalent to compacted clay or geomembrane liners. No statutory change or rulemaking would be required to revise the permit instructions to add self-sealing pond liners to the list of acceptable methods, although compelling scientific and engineering evidence would be necessary to justify such a modification.
The Texas Scientist, Issue 1, January 2014
(University of Texas at Austin, 2014-01) University of Texas at Austin