Showing papers on "Saline water published in 1984"

Use of saline water for irrigation

Abstract: Not available – first paragraph follows: Expansion of irrigated agriculture would contribute significantly toward meeting world food and fiber needs but, at the same time, would run headlong into competition for ever more limited water supplies. By reassessing the criteria for suitability of water (and land) for irrigation, however, available supplies can be expanded significantly. Very conservative standards have been used in the past. If these standards are relaxed, water generally classified as too saline for irrigation can often be used successfully without hazardous long-term consequences to crops or soils, even under conventional farming practices. Adoption of new crop and water management strategies would further facilitate the use of saline waters for irrigation and could make possible a sizable expansion of irrigated agriculture.

Salinity Effects on Seed Yield, Growth, and Germination of Grain Sorghum

Abstract: In field trials at Brawley, California, sorghum cv. Asgrow Double TX and Northrup King NK-265 were sown on silty clay in mid-May 1982, given adequate N and P fertilizer and irrigated with saline water (1:1 NaCl and CaCl2) of electrical conductivity 1.5-12.1 dS/m. Grain yield was unaffected by soil salinity up to 6.8 dS/m, but each subsequent increase in salinity of 1 dS/m reduced yield by 16%. Yield reduction was due primarily to a decrease in grain weight/ear rather than to a reduction in ear formation. Grain yield of Double TX was significantly higher than that of NK-265. Vegetative growth was less affected by soil salinity than was grain yield. Salinity up to 8.2 dS/m did not affect germination. Higher salt levels delayed germination but did not affect the final germination percentage. Sorghum was more salt tolerant at germination than at later growth stages

Issues and options

Abstract: As we look ahead, it is clear that there is no single solution to the problem of increasing salinization of California’s soils and water supplies. The San Joaquin and Imperial valleys are in semi-arid regions in which irrigation is essential for the production of crops. Although irrigation has made these two of the most agriculturally productive areas in the world, it has also created a serious challenge the accumulation of salt in the soil. As is pointed out in the preceding articles, nature is the major source of salts in our soils and water. Even high quality, “puren water contains salt enough so that each acre-foot of water used for irrigation adds 350 pounds of salt to the land. As this water evaporates and is used by plants, the salt is left behind, raising the salinity of the remaining water. Salt is also added as water passes through the soil and dissolves native salts. In poorly drained areas, the water table rises and eventually reaches the root zone of plants, injuring or weakening them, or causing them to die. There are three major options in addressing this challenge: (1) improved water management to reduce the amount used to irrigate crops, thereby reducing the amount of salt introduced to an area; (2) research to develop more salt-tolerant plants; and (3) development of satisfactory systems to drain salts away from agricultural areas. A significant effort in the first option is the California Irrigation Management Information System, a joint project of the University of California and the California Department of Water Resources. This project is designed to provide growers the information needed to make the most efficient use of irrigation water based on crop, soil type, method of irrigation, temperature, humidity, and other factors involved in plant development. Research by the University is aimed at finding the most critical points in a crop’s development when water is absolutely essential and even a modest shortage can dramatically reduce yield. We have learned that crops vary in their tolerance to salt during the growing period, opening the way to the use of water of different quality during various growth stages. A new management strategy developed for poorly drained areas is to plant deep-rooted crops such as safflower to “mine” water, removing enough from the soil to lower the water table. After salt is flushed deeper into the soil, a more shallow-rooted crop such as alfalfa can be safely planted. Recycling irrigation water to cut down the amount of new salt introduced to farmland is another management technique being investigated. Research to develop salt-tolerant plants may expand the range of crops grown and increase the salt tolerance of certain crops. Some crops such as cotton, barley, safflower, and sugarbeet are more tolerant to salinity than are such crops as beans and corn. World seed collections are being screened to locate useful plants that grow well under saline conditions; wild species are being sought to hybridize with domestic species; genetic engineering is being utilized to transfer salt-tolerance from one plant or organism to another. In addition to providing salt-tolerant. plants, research is contributing to our knowledge about the specific mechanisms used by plants to tolerate and in some cases to thrive in conditions of high salinity. Desalting to recover water is being explored in California and other fresh-water-deficient areas of the world. The technology, still under development, could reduce the new water required but it does not remove the salt from a region, and given the magnitude of the problem, it is questionable whether it would have a significant impact. Improved management can reduce the rate at which salt is accumulated in soil and water, and salt-tolerant plants will prolong the length of time the land can be cultivated, but they will not solve the salinity problem in California. Eventually a system must be developed to remove salt from the area. The ultimate solution, particularly in soils with an impermeable clay layer underneath, is to construct drains to remove salinized water from the area. The question then becomes what to do with this saline water. The options include evaporation, desalting, drainage into a salt sink or into the ocean, or a combination of all three. Evaporation will require an area equivalent to 15 to 20 percent of the acreage farmed and would still leave a salt disposal problem. This latter problem has become more complex, because drainage water from some areas also contains elements such as selenium and boron, which can accumulate to toxic levels. The Delta disposal plan described in the US. Bureau of Reclamation (San Luis Unit) Information Bulletin 1 (January 1984) appears to be the most comprehensive solution for the San Joaquin Valley. Salt water from the drain would be introduced into the Suisun Bay through diffuser pipes at times of peak water flow. A series of reservoirs along the drain would store the saline water before discharge, and monitor as well as isolate toxic substances. Treatment plants at the reservoirs would remove toxic substances from the water prior to release. Early-warning biological monitoring devices would be used to shut down the movement of water if the concentration of salt exceeded the dilution capacity of the Delta. The conclusion is that all options should be used, including the best irrigation and cropping management systems and the development of additional salt-tolerant crops. However, given the volumes of salt that are added with each irrigation, the long-term solution must be the removal of the salt from irrigated cropland of the San Joaquin and Imperial valleys.

Water use, growth and rubber yields of four guayule selections as related to irrigation regimes

Abstract: There has been renewed interest in cultivating guayule (Parthenium argentatum G.) for rubber production. Water use, growth and rubber yields of four guayule selections (593, 11.591, 11 646 and 4265 XF) were evaluated for two years in nonweighing field lysimeters at El Paso, TX. Four irrigation treatments were evaluated; these involved irrigation when about 40, 60 or 90% of available water was depleted, and the fourth treatment was irrigated at 60% depletion using saline water containing 3,300 mg of dissolved salts per liter. Water use for the two year period for these treatments amounted to 219, 147, 96 and 132 cm, respectively, plus biennial rainfall of 32 cm. Shrub and resin yields increased linearly with increasing irrigation, while rubber contents generally decreased with irrigation. Resultant rubber yields were highest under the lowest stress treatment, yielding about 840 kg/ha. Rubber yields with other treatments averaged 560 kg/ha with no significant yield differences among the tested selections. The salt treatment increased rubber contents of the shrubs, but caused reductions in shrub and rubber yields. Guayule plants survived well under low soil moisture, but water requirement to produce unit quantities of biomass was high (about 15 cm to produce one ton of dry shrub per ha). Guayule should not be regarded as a low water consuming crop if high yields per land area are to be achieved.

Barley yield under saline water cultivation

Abstract: In a microplot experiment conducted during the winter seasons of 1979–80 and 1980–81 on a sandy loam soil in the semi-desert tract, the accumulation of salts was found to be highest in March after harvest of the barley crop grown with saline water of EC values ranging from 22 to 24 mmhos/cm The average EC of saturation extract of the surface soil layer (0–15 cm) was 079 times that of the applied irrigation water at the time of crop harvest, however, accumulated salts of the winter season were leached by the following monsoon rains The average SAR of saturation extract of soil was 15 times that of the irrigation water in March but quite low in November Highly significant correlations, (+090 to 099) at the post irrigated period between ECse of soils and EC of waters and SARse of soils and SAR of waters have been observed Barley could be grown economically with irrigation water upto EC 16 mmhos/cm; however an average reduction in grain yield or not more than 435% compared to the yield under irrigation with tube well water of EC 22 mmhos/cm, was obtained The starch, N and P contents decreased and that of K and Na increased in the grain with the use of saline waters The performance of DL-85 variety was best and its K/Na ratio was also higher than that of other tested varieties

Subsurface Injection of Treated Sewage into a Saline‐Water Aquifer at St. Petersburg, Florida — Water‐Quality Changes and Potential for Recovery of Injected Sewage

Abstract: The city of St. Petersburg is testing subsurface injection of treated sewage into the Floridan aquifer as a means of eliminating discharge of sewage to surface waters and as a means of storing treated sewage for future nonpotable reuse. The injection zone at the test site at the start of injection contained saline water with chloride concentrations ranging from 14,000 to 20,000 milligrams per liter (mg/1). Treated sewage with a mean chloride concentration of 170 mg/1 was injected through a single well for 12 months at a mean rate of 4.7 × 105 cubic feet per day. The volume of water injected during the year was 1.7 × 108 cubic feet. Dissolved oxygen was contained in the sewage prior to injection. Water removed from the injection zone during injection was essentially free of oxygen. Probable growth of denitrifying bacteria and, thus, microbial denitri-fication, was suggested by bacterial counts in water from two observation wells that were close to the injection well. The volume fraction of treated sewage in water from wells located 35 feet and 733 feet from the injection well and open to the upper part of the injection zone stabilized at about 0.9 and 0.75, respectively. Chloride concentrations stabilized at about 1,900 mg/1 in water from the well that was 35 feet from the injection well and stabilized at about 4,000 mg/1 in water from the well that was 733 feet from the injection well. These and other data suggest that very little near injection-quality treated sewage would be recoverable from storage in the injection zone.

Trace Metals in the Columbia River Estuary Following the 18 May 1980 Eruption of Mount St. Helens

Abstract: Dissolved and suspended concentrations of cadmium, copper, iron, manganese, nickel, lead, and zinc were measured in the Columbia River Estuary following the 18 May 1980 eruption of Mount St. Helens. Soluble concentrations of these trace elements were not substantially elevated by the influx of volcanic ash and mud into the estuary during this period, except for somewhat higher than usual concentrations of manganese and copper. A laboratory experiment indicates that manganese leached from volcanic debris in fresh water and in the transition from fresh to slightly saline water probably caused the elevated Mn leaching from the material into fresh water.

A method for nitrate and phosphate in saline water1

Abstract: Ion chromatography, in combination with sample pretreatment, is shown to be useful as a method for the determination of phosphate and nitrate at ppm levels in saline water samples.

Purification of saline water

Abstract: PURPOSE: To rationalize the purification of saline water suitable for the alkali salt electrolysis by the ion exchange membrane process, by flocculating the saline water with an alkaline agent, and removing sulfate radical from the obtained slurry. CONSTITUTION: The crude saline water containing Mg ++ , Ca ++ and SO 4 -- is introduced into the mixing tank 1, mixed with caustic alkali, alkali carbonate, and a flocculant, and sent through the pipe 2 to the thickener 3. Mg ++ and Ca ++ are flocculated and precipitated in the form of magnesium hydroxide and calcium carbonate, respectively, and are extracted from the thickener to the precipitation tank 5. The obtained saline water slurry is added with barium carbonate and/or barium chloride to form the precipitate of barium sulfate. The precipitate is transferred through the pipe 6 to the filter press 7, and the filter cake and the recovered saline water are sent through the pipe 8 to the mixing than 1. The supernatant liquid of the thickener 3 is transferred through the pipe 9, the storage tank 10 and the pipe 11 to the filter 12, filtered, and supplied to the electrolytic cell. COPYRIGHT: (C)1986,JPO&Japio

Subsurface injection of treated sewage into a saline-water aquifer at St. Petersburg, Florida - Aquifer pressure buildup

Abstract: The city of St Petersburg has been testing subsurface injection of treated sewage into the Floridan aquifer as a means of eliminating discharge of sewage to surface waters and as a means of storing treated sewage for future non-potable reuse The injection zone originally contained native saline ground water that was similar in composition to sea water The zone has a transmissivity of about 12 X 106 feet squared per day (ft2/d) and is within the lower part of the Floridan aquifer Treated sewage that had a mean chloride concentration of 170 milligrams per liter (mg/1) was injected through a single well for 12 months at a mean rate of 47 X 105 cubic feet per day (ft3/d) The volume of water injected during the year was 17 X 108 cubic feet Pressure buildup at the end of one year ranged from less than 01 to as much as 24 pounds per square inch (lb/in2) in observation wells at the site Pressure buildup in wells open to the upper part of the injection zone was related to buoyant lift acting on the mixed water in the injection zone in addition to subsurface injection through the injection well Calculations of the vertical component of pore velocity in the semiconfining bed underlying the shallowest permeable zone of the Floridan aquifer indicate upward movement of native water This is consistent with the 200- to 600-mg/l increase in chloride concentration observed in water from the shallowest permeable zone during the test

Water relations of drought-resistant and drought-sensitive wheat cultivars sprinkled with saline water

Abstract: Water potential, osmotic potential, turgor potential, and stomatal resistance were measured on leaves of a drought-sensitive (‘Ponca’) and a drought-resistant (‘KanKing’) cultivar of winter wheat (Triticum aestivum L.) treated with foliar applications of NaCl to determine the effect of salt on the water status of two cultivars varying in drought resistance. Plants were grown under controlled conditions in soil, which was watered or allowed to dry. Water potential of the soil was determined. Given an ample water supply, water potential and osmotic potential of leaves of both cultivars with NaCl were lower, and stomatal resistance was higher, than without NaCl. The combination of salt and drought killed both cultivars, but the turgor potential of the drought-sensitive cultivar with the two stresses reached zero before that of the drought-resistant cultivar. Under limited water supply, both cultivars with foliar applications of salt extracted more water from soil than they did with no salt, and the drought-resistant cultivar took up more water than did the drought-sensitive cultivar. The drought-resistant cultivar with foliar NaCl maintained a higher turgor potential and extracted more water from the drying soil than did the drought-sensitive cultivar with foliar NaCl, suggesting that the drought-resistant cultivar was also more salt tolerant.

Effects of increasing drainage in the San Joaquin Valley

Abstract: Not available – first paragraph follows: Most soil salinity problems in the San Joaquin Valley are directly related to shallow saline water tables. Where no such water tables exist, soil salinity problems usually do not occur, because irrigation water used in the Valley is generally very low in salts.

Ground-water resources of St Johns County, Florida

Abstract: The two primary sources of ground water in St. Johns County are the surficial and Floridan aquifers. The surficial aquifer is the principal source of water supply for drinking and domestic purposes in most of the county. The Floridan aquifer is the major source of water supply for irrigation use. In most of the county, water from the Floridan aquifer does not meet drinking water standards for some characteristics. Available supplies of potable water from the surficial aquifet are adequate to meet short-term increases in demand, but future growth will require additional sources of potable water. The surficial aquifer is present throughout the county and extends from land surface to a maximum depth of about 120 feet. The aquifer is recharged primarily by rainfall and in some areas by infiltrating irrigation water withdrawn from the Floridan aquifer. The Floridan aquifer underlies the county at a depth of about 90 to more than 360 feet below sea level. Recharge to the aquifer is almost entirely from the lake region in Alachua, southwestern Clay, eastern Bradford, and western Putnam Counties. Discharge is from springs, from wells used for irrigation, and by upward leakage. Withdrawal of large quantities of water from the Floridan aquifer has caused declines in the potentiometric surface. During the spring, when withdrawal is heaviest and rainfall is lightest, the potentiometric surface is lowered an average of about 5 feet throughout the county and a maximum of about 15 feet in the agricultural areas. Comparison of predevelopment water levels with 1980 water levels indicates that withdrawals of water Afor irrigation and public supply have lowered the potentiometric surface about 10 to 20 feet throughout most of the county. Water from the surficial aquifer generally meets most of the secondary drinking-water quality standards in most of the county and is satisfactory for most uses. Concentrations of sulfate and chloride generally do not exceed 250 milligrams per liter in St. Johns County, and only in a small part of the county do dissolved-solids concentrations exceed 500 milligrams per liter. Iron concentrations commonly exceed 0.3 milligrams per liter. In most of St. Johns County, water from the Floridan aquifer is more saline than water from the surficial aquifer. Variations in the concentrations of chemical constituents occur both areally and with depth. Highly saline water is present in the upper part of the aquifer in most of the southern part of the county. The presence of saline water and the dissolution of gypsum and anhydrite are the primary factors that govern water quality in the aquifer. In the southwest part of the county* intensive pumpage for irrigation has resulted in substantial increases in chloride concentration caused primarily from the upconing of more saline water.

Osmotic Adjustment and Chlorophyll Fluorescence in Water- and Salt-Stressed Plants

Abstract: Several changes specific to the light reactions of photosynthesis have been documented for plants experiencing water stress. For example, loss of chlorophyll avariable fluorescence, indicative of a sensitive site on the oxidizing side of photosystem II, has been correlated with impaired electron transport in leaves of water-stressed Nerium oleander (Bjorkman et al. 1980; Bjorkman et al. 1981; Govindjee et al. 1981). The application of saline water to plants can also lower leaf water potential (Downton, Loveys 1981). This paper examines the responses of grapevine leaves to water and salt stress, and shows that changes in leaf variable fluorescence depend upon light intensity and the maintenance of turgor pressure.

Geohydrology and chemical quality of water in middle and upper jurassic and lower cretaceous rocks, western kansas

Abstract: An investigation of permeable units in Middle and Upper Jurassic and Lower Cretaceous rocks was made, in cooperation with the Kansas Department of Health and Environment, to define and update data on the geohydrology and chemical quality of water and to regionalize the results for about 12,700 square miles in 15 counties in western Kansas. The consolidated formations considered include rocks equivalent to the undifferentiated Middle and Upper Jurassic Entrada Sandstone and Morrison Formation and the Lower Cretaceous Cheyenne Sandstone, Kiowa Formation, and Dakota Formation. The rocks equivalent to the undifferentiated Entrada Sandstone and Morrison Formation occur in the subsurface in the western two-thirds of the area at depths ranging from about 300 to about 2,500 feet. The rocks consist of varicolored sandstone, siltstone, shale, and limestone. Maximum thickness is about 200 feet. The Cheyenne Sandstone occurs at depths ranging from about 200 to about 2,500 feet in the subsurface throughout the area, except along the south-central boundary. The rocks consist of white, brown, and gray, very fine to medium-grained sandstone and dark-gray shale. Maximum formation thickness is about 200 feet. The Kiowa Formation occurs in the subsurface except along the south-central boundary. The rocks to black shale with interbedded siltstone, sandstone, mum formation thickness is about 190 feet. throughout the area, consist of light-gray and limestone. MaxiThe Dakota Formation occurs at the land surface in five counties as isolated outcrops and in the subsurface at depths of more than 2,000 feet in Wallace County, except along the south-central boundary, consist of varicolored sandstone, shale, and siltstone with Maximum formation thickness is about 400 feet. The rocks some lignite. The Jurassic aquifer is defined as permeable and saturated sandstone and siltstone units equivalent to the undifferentiated Entrada Sandstone and Morrison Formation. The maximum total thickness of the sandstone beds is about 50 feet. During 1981, depths to water in three test wells completed in the aquifer ranged from 255 to 1,160 feet; static heads aquifer ranged from 2,408 to 3,090 feet sandstone tested in the Burnett No. 1 percent. The hydraulic gradient ranged northeast to 40 feet per mile toward the above sea level, well ranged from from 16 feet per north. in the artesian Porosity of the about 19 to 25 mile toward the The Cheyenne aquifer is defined as permeable and saturated sandstone units in the Cheyenne Sandstone. The maximum total thickness of the sandstone beds is about 190 feet. During 1981, depths to water in three test wells completed in the aquifer ranged from 267 to 375 feet; static heads in the artesian aquifer varied from less than 2,300 to more than 3,200 feet above sea level. Porosity of the sandstone tested in Burnett No. 1 well ranged from about 23 to 32 percent. The hydraulic gradient was toward the east at 8 feet per mile. The Dakota aquifer is defined as saturated permeable sandstone units in the Dakota Formation. The maximum total thickness of the sandstone beds is about 150 feet. During 1982, depths to water in wells completed in the aquifer ranged from 24 to 604 feet; static heads in the artesian aquifer ranged from about 2,100 to 3,200 feet. The hydraulic gradient was toward the east and northeast at 11 feet per mile. Transmissivity ranged from about 100 to 2,100 feet squared per day; specific capacity, from about 2.5 to 13 gallons per minute per foot of drawdown; storage coefficients, from 1 x 10'4 to 4 x 10' 3 ; and well yields, from about 150 to 1,200 gallons per minute. Water in the Jurassic aquifer, where sampled in Hamilton and Kearny Counties, is moderately saline, very hard, and unsuitable for drinking and irrigation. Sodium is the predominant cation in the water, and sulfate and chloride are the predominant anions. The most likely sources of saline water are from the natural dissolution of minerals and from interstitial saline water. Water in the Cheyenne aquifer, where sampled in Hamilton and Kearny Counties, is fresh to moderately saline, locally can vary from soft to very hard, and is suitable to unsuitable for drinking and irrigation. Sodium is the predominant cation, and sulfate and bicarbonate are the predominant anions. Water in the Dakota aquifer, where sampled in five counties, generally is fresh, soft to very hard, and suitable for drinking and irrigation. However, the water is slightly to moderately saline, soft to moderately hard, and unsuitable for drinking and irrigation in parts of Hamilton County. Sodium and calcium are the predominant cations, and bicarbonate, sulfate, and chloride are the predominant anions. The chemical type of water may vary locally. The slightly saline waters are sodium sulfate and sodium chloride types, and the moderately saline water is a calcium sulfate type. Ground water in all three aquifers is suitable for various uses that include domestic, stock, irrigation, public, and industrial water systems. The Jurassic and Cheyenne aquifers generally have had very little well development; however, the Dakota aquifer has had considerable development, but it is still considered underdeveloped in most localities.

Storage of raw laver

Abstract: PURPOSE:Saline water is shielded from direct sunlight and kept cool, then raw laver collected from the sea is charged into the water and stirred under such conditions as oxygen is dissolved therein to prevent the raw laver for sheet-making from quality deterioration. CONSTITUTION:Saline water 1 in the water tank 3 is made to contain dissolved oxygen by e.g., spraying the water in the air 4 and kept at about 5-10 deg.C with pipe 5 using sensors and controllers. The water tank 3 is shield from direct sunlight with covers or roofs and raw laver collected from the sea is charged into the cooled saline water 1. Then, the saline water 1 and raw laber are stirred with the blades 7 of the stirrer 6 in the tank 3 to remove diatoms, contaminants, bacteria and other foreign substances sticking to the lavers 2 such as sand. The contaminants separated in washing are removed in the washing process after mincing process and the washed raw laver is sent to the sheet-making process.

Preparation of laver sheet

Abstract: PURPOSE:To reduce the consumption of fresh water, and to lower the production cost of laver sheet, by filtering the waste water exhausted from the fresh water- consuming process of a laver sheet preparation plant, desalting the filtrate, and recycling the desalted fresh water to the fresh water-consuming process CONSTITUTION:The fresh agar for the preparation of laver sheet is introduced into the saline water-consuming process 7, and subjected to the storage under cooling, the washing, etc using saline water such as sea water The agar is then introduced to the fresh water-consuming process 8 to effect the aging, straining, etc using fresh water The waste water D1 exhausted from the fresh water- consuming process 8 is filtered by the filtration apparatus 11 and desalted by the desalination apparatus 13, and the desalted fresh water D3 is recycled and reused in the fresh water-consuming process 8 Preferably, the concentrated saline water D4 exhausted from the desalination apparatus 13 is adjusted to about the salt content of sea water, and supplied to the saline water-consuming process 7 The consumption of fresh water and sea water can be remarkably reduced by this process

Salt Gradient Ponds: Investment Timing Model

Abstract: Salt gradient solar ponds can play an important role in management of river salinity in semiarid locations such as the Colorado River Basin. A mathematical model and solution procedure are presented for investment timing of expansion of a salt gradient pond system. An application of the model is presented for several sites in the upper Colorado River basin where planned fossil fuel electric generating plants are located near existing source of saline or brackish water. The concept involves use of both concentrated brine waste streams from the power plants and the existing low quality water sources for the pond system water and salt demands. The salt gradient pond can: (1) Replace a power plant's customary zero discharge evaporation; (2) produce additional energy; and (3) remove much more salt from the river system than the conventional evaporation pond. An economic model solution procedure and application are presented for expansion of salt gradient solar pond systems. Such systems have important potential for salinity management applications, when used in conjunction with thermal/electric plants near sources of saline water.

The production of distilled water using waste heat from the jacket-cooling water of diesel engines

Abstract: This paper presents a system where waste heat from the jacket-cooling water of diesel engines is used to drive a multieffect saline water distillation plant. Economic analysis of the cost of distilled water is presented using the waste heat from the jacket-cooling water of a 1000 kw diesel engine. The analysis shows that enhancing the heat-transfer coefficient per unit cost of heat-transfer surface in the distillation section results in lower distilled water cost as well as increasing the water output. The paper then presents a case study where the wiped-film rotating-disk evaporator, developed and tested at this Center, is used as the main element in the multieffect section. Using seawater feed, this case study shows that as much as 500 m3 per day of distilled water can be produced economically from this waste heat source.