Maintenance of Brine Transparency in Salinity Gradient Solar Ponds

1990 ◽  
Vol 112 (2) ◽  
pp. 65-69 ◽  
Author(s):  
J. R. Hull
Keyword(s):  
Aluminum Sulfate ◽  
Salinity Gradient ◽  
National Laboratory ◽  
Argonne National Laboratory ◽  
Algal Growth ◽  
Soluble Phosphate ◽  
Phosphate Content ◽  
Solar Ponds ◽  
Solar Pond ◽  
Good Transparency

Experience with maintenance of brine transparency during the more than eight years of operation of the 1000 m2 Research Salinity Gradient Solar Pond (RSGSP) at Argonne National Laboratory suggests that, in many sodium chloride brines, algal growth may be readily curtailed by minimizing the phosphate content of the brine. The addition of modest amounts of aluminum sulfate (<5 g m−2 yr−1) to precipitate soluble phosphate in the RSGSP has resulted in a reduction of the amount of chlorine used from 13 g m−2 yr−1 to 2.8 g m−2 yr−1, while still maintaining good transparency in the pond brine.

Depth Sounding Diagnostic Measurements of Salt Gradient Solar Ponds

1985 ◽  
Vol 107 (2) ◽  
pp. 160-164 ◽  
Author(s):  
T. A. Newell ◽  
J. R. Hull
Keyword(s):  
National Laboratory ◽  
Argonne National Laboratory ◽  
Lower Boundary ◽  
Gradient Zone ◽  
Solar Ponds ◽  
Solar Pond ◽  
Side Walls ◽  
Salt Gradient ◽  
Depth Sounding

A recording depth sounding instrument has provided several different diagnostic measurements in the 1000 m2 Research Salt Gradient Solar Pond at Argonne National Laboratory. The sounder has been used to locate gradient zone boundaries and layers of debris within the pond. The instrument has also helped to verify that the presence of salt piles in the bottom of the pond has been responsible for automatically maintaining the constant position of the gradient zone lower boundary during the last three years. Subsurface waves have been observed at the bottom of the gradient zone near the pond side walls. The sounding instrument has also proved capable of identifying density driven plumes and turbulent disturbances within the pond.

Thermal Heat Storage Gain of Salinity Gradient Solar Pond Using Evacuated Tube Solar Collectors

2015 ◽  
Vol 1113 ◽  
pp. 800-805 ◽  
Author(s):  
Baljit Singh ◽  
Muhammad Fairuz Remeli ◽  
Alex Pedemont ◽  
Amandeep Oberoi ◽  
Abhijit Date ◽  
...  
Keyword(s):  
Large Scale ◽  
Heat Storage ◽  
Salinity Gradient ◽  
Heat Energy ◽  
Working Fluid ◽  
The Sun ◽  
Solar Ponds ◽  
Solar Pond ◽  
Evacuated Tube Collectors ◽  
Evacuated Tube

This paper investigates the capability of running a system which uses hot fluid from solar evacuated tube collectors to boost the temperature and overall heat storage of the solar pond. The system is circulated by a solar powered pump, producing heat energy entirely from the incoming solar radiation from the sun. Solar evacuated tube collectors use a renewable source of power directly from the sun to heat the working fluid to very high temperatures. Solar ponds are emerging on the renewable energy scene with the capacity to provide a simple and inexpensive thermal storage for the production of heat on a large scale. The results of the performance of the system show a significant heat energy increase into the solar ponds lower convective region, increasing the overall performance of the solar pond.

The Influence of Height of LCZ on the Salinity Diffusion of Solar Pond

2013 ◽  
Vol 448-453 ◽  
pp. 1521-1524
Author(s):  
Chun Juan Gao ◽  
Qi Zhang ◽  
Hai Hong Wu ◽  
Liang Wang ◽  
Xi Ping Huang
Keyword(s):  
Solar Energy ◽  
Fresh Water ◽  
Salt Water ◽  
Salinity Gradient ◽  
Good Method ◽  
Convective Zone ◽  
Solar Ponds ◽  
Solar Pond ◽  
Salt Gradient ◽  
And Diffusion

The solar ponds with a surface of 0.3m2were filled with different concentration salt water and fresh water. The three layer’s structure of solar ponds was formed in the laboratory ponds by using the salinity redistribution. The performance and diffusion of salinity were xperimentally in the solar pond. The measurements were taken and recorded daily at various locations in the salt-gradient solar pond during a period of 30 days of experimentation. The experimental results showed that the salinity gradient layer can sustain a longer time when the lower convective zone is thicker, which is benefit to store solar energy. Therefore, properly increasing the height of LCZ is a good method to enhance the solar pond performance.

Effect of Water Distribution Ways on the Operation of Solar Pond

2013 ◽  
Vol 805-806 ◽  
pp. 74-77
Author(s):  
Chun Juan Gao ◽  
Qi Zhang ◽  
Liang Wang ◽  
Ying Wang ◽  
Xi Ping Huang
Keyword(s):  
Water Distribution ◽  
Salinity Gradient ◽  
Convective Zone ◽  
The Body ◽  
Solar Ponds ◽  
Solar Pond ◽  
Storage Zone ◽  
Small Model ◽  
Laboratory Tank ◽  
Salt Diffusion

An experimental study on the evolution of the salinity profiles in the salinity gradient solar ponds was executed using a small model pond. The body of the simulated pond is a cylindrical plastic tank, with 50 cm height and 45 cm diameter. The salinity gradient was established in the laboratory tank by using the salinity redistribution technique. The measurements were taken during a period of 20 days of experimentation. This period of time allowed the existence of salt diffusion from the storage zone to the surface. Results obtained from this study show that when the ratio of brine/water is 1/1, the salinity gradient layer can sustain a longer time and the lower convective zone is thicker, which is benefit to store solar energy.

Two-Dimensional Computer Simulation of Salinity Gradient Solar Pond Operation

2014 ◽  
Author(s):  
Minoo Mehdizadeh ◽  
Goodarz Ahmadi
Keyword(s):  
Solar Radiation ◽  
Salt Concentration ◽  
Numerical Study ◽  
Fluid Dynamic ◽  
Salinity Gradient ◽  
Radiation Absorption ◽  
Small Scale ◽  
Two Dimensional ◽  
Solar Ponds ◽  
Solar Pond

This study is concerned with computer modeling of flow and thermal analysis of solar ponds with a salinity gradient. Solar ponds have been used as an efficient and environmentally friendly approach for collection of solar energy for low temperature thermal applications. A two-dimensional unsteady computational fluid dynamic (CFD) model was developed and used for numerical study of stability analysis of the pond, as well as heat and mass transfer in the salt gradient solar ponds. Salinity gradient was created in order to stabilize the pond and to restrict convective motions induced by buoyancy driven solar radiation heating during the period of operation. Fluent® commercial software was enhanced with the implementation of User Defined Functions (UDF) and was used in these simulations. The user defined scalar model was included for analyzing the convection and diffusion of the salt concentration in the solar pond. In addition, user defined functions were developed for relating the water density to temperature and salt concentration, as well as, the amount of solar radiation absorption in the solar pond as functions of thermo-physical properties. In the absence of flow exchange, the natural convection in the pond was simulated and the stability of the pond was verified. Development of salt concentration was also studied, and time evolution of temperature distribution in a small scale salinity gradient solar pond was analyzed. For the case of flow exchange at the bottom of the pond, the energy production was evaluated, and the temperature, concentration and flow field were simulated.

Gradient-Zone Erosion by Extraction in Solar Ponds

1995 ◽  
Vol 117 (2) ◽  
pp. 144-150 ◽  
Author(s):  
J. Estevadeordal ◽  
S. J. Kleis
Keyword(s):  
Steady State ◽  
Salinity Gradient ◽  
Operating Conditions ◽  
Density Difference ◽  
Finite Density ◽  
Gradient Zone ◽  
Solar Ponds ◽  
Solar Pond ◽  
Flow Parameters ◽  
Storage Zone

The erosion the dynamically stable gradient zone of a salinity-gradient solar pond, due to the extraction of fluid from the storage zone, is numerically investigated. The effects of fluid withdrawal rate, density stratification level, pond and diffuser geometries, and diffuser placement are considered. It is found, for a typical salinity-gradient solar pond with uniform salinity in the storage zone and a continuous salinity gradient above that a finite amount of fluid entrainment from the gradient zone is inevitable. That is, a finite density difference across the interface is always required for a finite extraction rate under steady-state conditions. The magnitude of the density difference is predicted as function of the geometric and flow parameters. From the results, it is possible to predict the total amount of fluid entrained from the gradient zone as the pond reaches steady-state for prescribed operating conditions.

Double Diffusive Natural Convection in Solar Ponds With Nonlinear Temperature and Salinity Profiles

1986 ◽  
Vol 108 (3) ◽  
pp. 214-218 ◽  
Author(s):  
A. T. Kirkpatrick ◽  
R. F. Gordon ◽  
D. H. Johnson
Keyword(s):  
Fluid Layer ◽  
Salinity Gradient ◽  
Radius Of Curvature ◽  
Length Scale ◽  
Solar Ponds ◽  
Solar Pond ◽  
Thin Region ◽  
Nonlinear Temperature ◽  
Set Up ◽  
The Stability

A solar pond can be used as a thermal energy source provided that convective instabilities do not occur. This paper experimentally examines the stability of a fluid layer with nonlinear salinity and temperature profiles. A nonlinear salt profile was set up in a fluid layer, and the water was heated by a solar radiation simulator. Three stability experiments were conducted. Instabilities occurred at the location of the weakest salinity gradient, and were confined to a thin region, as predicted by theory. A local length scale was used to produce a stability parameter, the ratio of thermal to solute Rayleigh numbers. It is shown that for nonconstant solute and temperature gradients, the appropriate length scale is based on the radius of curvature of the salinity distribution. With this chocie of a length scale, good agreement was found between theory and experiment for the onset of an instability.

Advancements in Salinity Gradient Solar Pond Technology Based on Sixteen Years of Operational Experience

2004 ◽  
Vol 126 (2) ◽  
pp. 759-767 ◽  
Author(s):  
Huanmin Lu ◽  
Andrew H. P. Swift ◽  
Herbert D. Hein, ◽  
John C. Walton
Keyword(s):  
Salinity Gradient ◽  
El Paso ◽  
Industrial Process ◽  
Economic Feasibility ◽  
Heat Extraction ◽  
Injection Technique ◽  
Operational Experience ◽  
Solar Ponds ◽  
Solar Pond ◽  
Analysis Strategy

The El Paso salinity gradient solar pond, initiated in 1983, has been in operation since 1985. Through 16 years of research and operation, the El Paso Solar Pond has successfully demonstrated applications including desalination, waste brine management, industrial process heat production, and electricity generation; and has developed and implemented key technical advancements to improve the technical viability and economic feasibility of salinity gradient solar ponds, including: 1) an automated instrumentation monitoring system, 2) a stability analysis strategy and high temperature (60–90°C) gradient maintenance methods, 3) a scanning injection technique for improved salinity gradient construction and maintenance, 4) new liner technology, and 5) an improved heat extraction system.

Electron and ion irradiation-induced dissolution of mechanical twins in the intermetalic U3Si: An in situ HVEM study

1989 ◽  
Vol 47 ◽  
pp. 652-653
Author(s):  
Charles W. Allen ◽  
Robert C. Birtcher
Keyword(s):  
Elevated Temperatures ◽  
Ion Irradiation ◽  
Ion Beam ◽  
National Laboratory ◽  
Argonne National Laboratory ◽  
Heavy Ion ◽  
High Energy ◽  
Mechanical Twinning ◽  
In Situ Experiments

The uranium silicides, including U3Si, are under study as candidate low enrichment nuclear fuels. Ion beam simulations of the in-reactor behavior of such materials are performed because a similar damage structure can be produced in hours by energetic heavy ions which requires years in actual reactor tests. This contribution treats one aspect of the microstructural behavior of U3Si under high energy electron irradiation and low dose energetic heavy ion irradiation and is based on in situ experiments, performed at the HVEM-Tandem User Facility at Argonne National Laboratory. This Facility interfaces a 2 MV Tandem ion accelerator and a 0.6 MV ion implanter to a 1.2 MeV AEI high voltage electron microscope, which allows a wide variety of in situ ion beam experiments to be performed with simultaneous irradiation and electron microscopy or diffraction.At elevated temperatures, U3Si exhibits the ordered AuCu3 structure. On cooling below 1058 K, the intermetallic transforms, evidently martensitically, to a body-centered tetragonal structure (alternatively, the structure may be described as face-centered tetragonal, which would be fcc except for a 1 pet tetragonal distortion). Mechanical twinning accompanies the transformation; however, diferences between electron diffraction patterns from twinned and non-twinned martensite plates could not be distinguished.

Environmental cell studies of deformation and fracture

1990 ◽  
Vol 48 (4) ◽  
pp. 516-517
Author(s):  
H. K. Birnbaum ◽  
I. M. Robertson
Keyword(s):  
National Laboratory ◽  
Argonne National Laboratory ◽  
Damage Threshold ◽  
Chromatic Aberration ◽  
Good Choice ◽  
Point Of View ◽  
Deformation And Fracture ◽  
Environmental Cell ◽  
Gas Molecules ◽  
The University

Studies of the effects of hydrogen environments on the deformation and fracture of fcc, bcc and hep metals and alloys have been carried out in a TEM environmental cell. The initial experiments were performed in the environmental cell of the HVEM facility at Argonne National Laboratory. More recently, a dedicated environmental cell facility has been constructed at the University of Illinois using a JEOL 4000EX and has been used for these studies. In the present paper we will describe the general design features of the JEOL environmental cell and some of the observations we have made on hydrogen effects on deformation and fracture.The JEOL environmental cell is designed to operate at 400 keV and below; in part because of the available accelerating voltage of the microscope and in part because the damage threshold of most materials is below 400 keV. The gas pressure at which chromatic aberration due to electron scattering from the gas molecules becomes excessive does not increase rapidly with with accelerating voltage making 400 keV a good choice from that point of view as well. A series of apertures were placed above and below the cell to control the pressures in various parts of the column.

Sign in / Sign up

Export Citation Format

Share Document