Mechanical and thermal tests of a bentonite clay for use as a liner for solar ponds

Journal Article · Mon Jan 01 04:00:00 EST 1990 · Solar Energy (Journal of Solar Energy Science and Engineering); (USA)

DOI:https://doi.org/10.1016/0038-092X(90)90092-Q· OSTI ID:6193328

Almanza, R; Lozano, M C ^[1]

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1. Universidad Nacional Autonoma de Mexico, Mexico City (Mexico)

The use of clays has been discussed as an alternative for liners in solar ponds. The bentonite used in this experiment was a Ca-montmorillonite. It has a thermal conductivity of 1.14 W/m{degree}C at 50{degree}C before being under the influence of NaCl brine, and a value of 0.42 W/m{degree}C at the same temperature after four months under the influence of the NaCl hot brine. When fresh hot water was used at a temperature of 50{degree}C, the vertical permeability was 1.3 {times} 10{sup {minus}7} cm/s. After the four months under the hot brine, salinity saturation in the effluent became 70% after filtering it through the clay, and 1.09 {times} 10{sup {minus}7} cm/s was the lower permeability reached. Under drastic changes in temperature (10{degree}C or more) the clay starts to form small fissures that increase permeability. However, if these severe changes are not carried out in a solar pond, the clay can be used as a liner. Therefore, it is possible to state that the thermal conductivity and the permeability of this clay are better than those of a kaolinite clay. These properties are reduced by the influence of a hot brine during long exposure periods due to the ion exchange which permits it to be used as a liner.

• OSTI ID: 6193328
• Journal Information: Solar Energy (Journal of Solar Energy Science and Engineering); (USA), Journal Name: Solar Energy (Journal of Solar Energy Science and Engineering); (USA) Vol. 45:4; ISSN SRENA; ISSN 0038-092X
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
141000* -- Solar Collectors & Concentrators
ALKALI METAL COMPOUNDS
ALUMINIUM COMPOUNDS
ALUMINIUM SILICATES
BRINES
CHLORIDES
CHLORINE COMPOUNDS
CLAYS
COMPARATIVE EVALUATIONS
EQUIPMENT
HALIDES
HALOGEN COMPOUNDS
HOT WATER
HYDROGEN COMPOUNDS
INORGANIC ION EXCHANGERS
ION EXCHANGE
ION EXCHANGE MATERIALS
KAOLINITE
LINERS
MATERIALS
MATERIALS TESTING
MEASURING INSTRUMENTS
MECHANICAL PROPERTIES
MECHANICAL TESTS
MINERALS
MOISTURE
MONTMORILLONITE
OXYGEN COMPOUNDS
PERFORMANCE TESTING
PERMEABILITY
PHYSICAL PROPERTIES
PLASTICITY
PONDS
SALINITY
SATURATION
SILICATE MINERALS
SILICATES
SILICON COMPOUNDS
SODIUM CHLORIDES
SODIUM COMPOUNDS
SOLAR COLLECTORS
SOLAR EQUIPMENT
SOLAR PONDS
SURFACE WATERS
TEMPERATURE EFFECTS
TESTING
THERMAL CONDUCTIVITY
THERMAL DIFFUSIVITY
THERMODYNAMIC PROPERTIES
TIME DEPENDENCE
WATER