Solar evaporation systems

The last classification includes the solar evaporation system, the oldest evaporation principle employed by man and, in concept, the simplest evaporation technique. Solar evaporators require tremendous land areas and a relatively cheap raw material, since pond leakage may be appreciable. Solar evaporation generally is feasible only for the evaporation of natural brines, and then only when the water vapor is evaporated into the atmosphere and is not recovered. 

Anonymous. 1992. Optimization of Solar Evaporation Systems, "Phosphorus and Potassium, No. 179(May-June) 17-25. 

The potassium sulfate and boric acid plants (Fig. 1.66 with capacities of 250,000 and 16,000 mt/yr, respectively) started production in 1998 using a separate brine supply and solar evaporation system. After the brine had left the initial halite ponds all of the potassium and sulfate salts were allowed to crystallize and be harvested together from one set of ponds. In 2002 the first processing step was to leach its halite content, and then convert the residue to schoenite with return liquor from... 

Solar evaporation Solarization Solar panels Solar ponds Solar power systems Solar radiation Solar salt... 

Th ese manufactured light sources are, perhaps ironically, largely dependent on the Sun. The radiant energy from the Sun has been stored in the fossilized remains of billions of creatures over millions of years and is used to power the electric light sources created by modern humans. The power generated by hydroelectric sources also is a result of solar evaporation and subsequent rainfall. Only nuclear reactors provide power independent of the Sun, which is, of course, the largest nuclear reactor in the solar system. 

Natural brines flowing through salt-dissolution cavities at Big Salt Plain commonly are saturated with respect to salt. The concentration of NaCl in brine from one well is 337 g/1, and (Na + Cl) constitute 98% of all dissolved solids in the brine (Table I). The large quantity of brine locally present in the cavern system is evident from the fact that this brine is pumped at rates of 2000—40001/min. from wells 12—30 m deep for commercial production of salt by solar evaporation (Johnson, 1970). Not all brines in the area are salt-saturated mixing of brine with near-surface fresh water dilutes the brine in some parts of the salt plains. 

An economic production of thin film solar cells however can only be achieved with large area evaporation systems with a material yield of more than 50 %. Such a system cannot be realized by one "point source" but requires several sources distributed within short distances below the substrate area in order to get small material losses at the edges and uniform thickness of the film /4/. 

SRIP). Many laboratories extensively characterized this family of proteins with a battery of diverse techniques, because they provide excellent model systems for the two fundamental functions of membranes active transport and sensory signaling. Twenty-nine variants of BR, HR, SRI, and SRII were documented in related extremely halophlHc archaea, such as Natronomonas pharaonis and Haloarcula vallismortis. Members of the archaeal rhodopsin family were generally assumed to be only in the haloarchaea and appeared to be restricted to the extreme halophilic environments of solar evaporation ponds and other regions of near-saturated salt concentration. 

The Zag meteorite fell in the western Sahara of Morocco in August 1998. This meteorite was unusual in that it contained small crystals of halite (table salt), which experts believe formed by the evaporation of brine (salt water). It is one of the few indications that liquid water, which is essential for the development of life, may have existed in the early solar system. The halite crystals in the meteorite had a remarkably high abundance of 128Xe, a decay product of a short-lived iodine isotope that has long been absent from the solar system. Scientists believe that the iodine existed when the halite crystals formed. The xenon formed when this iodine decayed. For this reason, the Zag meteorite is believed to be one of the oldest artifacts in the solar system. In this lab, you will use potassium-argon radiochemical dating to estimate the age of the Zag meteorite and the solar system. 

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