Thermal Brine

Bjoernsson, S., Arnorsson, S. and Tomasson, J., 1972. Economic evaluation of Reykjanes thermal brine area, Iceland. Am. Assoc. Petrol. Geol. Bull., 56 2380—2391. 

Membrane Distillation (MD) is a hybrid thermal-membrane process that could be applied in produced water volume reduction applications while simultaneously augmenting sustainable water production in Qatar. A consortium of ConocoPhillips - Global Water Sustainability Center (GWSC), Qatar University (QU) and Qatar Electricity Water Company (QEWC), was formed to assess the suitability of MD to treat high salinity brines from thermal desalination plants similar salinity levels could be found in produced water. The pilot scale results showed that MD could operate at 50% recovery and achieve a stable flux of 5 L/(m. h) at when treating thermal brine at 70,000 mg/L TDS. The effluent produced contained < 10 mg/L TDS. 

The thermal brine from local desalination plant was pretreated using a two-step filtration system (1pm + granular activated carbon) to remove particulates and organic contaminants present in the feed stream that could potentially affect the hydrophobicity of the membranes. This conservative pretreatment gave both systems the best chance of success. 

As shown in Figure 5, pilot unit A maintained a stable flux of 4.5 1/m. h for over 11 days when operating on thermal brine (70 g/L TDS) and 35% recovery. Product conductivity was consistently below 10 mg/L TDS. Table 1 shows the water quality analysis of major anions and cations. Salt rejections greater than 99.9% were achieved. 

Figure 5 Pilot unit a performance on thermal brine...

Parameter IJ nits Thermal Brine (N=4) Distillate (N=4) Reject Brine (N=4) Rejection (%)... 

When operated at a feed thermal brine TDS of 70 g/L and a 50% recovery rate, pilot unit A was able to desalinate brines from thermal desalination plants and consistently produce a high quality distillate (conductivity < 10 pS/cm - >99.99% rejection). 

Keywords Produced water, forward osmosis, thermal brine, volume reduction 1. Introduction... 

The primary disadvantage with FO is typically the input energy needed in step 2 to recover the water from the draw solution. The novel aspect of this project is to eliminate step 2 by to using seawater or thermal brine to draw water from the produced water and then directly discharge the diluted seawater/brine into the Arabian Gulf. This is particularly applicable in Qatar since both the desalination plant and the produced water from the gas fields are in close proximity to each other. 

Figure 2.12 Location Map for the Reykjanes Thermal Brine Area, Iceland (Bjomsson et al, 1972 reprinted from the AAPG Bulletin. AAPG 1972, reprinted by permission of the American Association of Petroleum Geologists, whose permission is required for further use).

Figure 2.13 Location of the Red Sea Thermal Brines, Metal Deposit, and the Danakil Depression (Bonatti et al, 1972 reprinted with permission from Economic Geology, vol. 67 6, p. 718, Fig. 1, Bonatti, E., Fisher, D. E. Joensu, O., Rydell, H.S. and Beyth, M., 1972).

Dead Seas Periclase Ltd., on the Dead Sea in Israel, uses yet another process to produce magnesium oxide. A concentrated magnesium chloride brine processed from the Dead Sea is sprayed into a reactor at about 1700°C (127,128). The brine is thermally decomposed into magnesium oxide and hydrochloric acid. To further process the magnesia, the product is slaked to form magnesium hydroxide which is then washed, filtered, and calcined under controlled conditions to produce a variety of MgO reactivity grades. A summary of MgO purities, for the various processes is given in Table 20. 

Occurrence. Brine found in Seades Lake, California is the only brine source where boron is produced commercially. Other brine bodies such as the Great Salt Lake or brine from thermal weUs at the Salton Sea have been considered but have not been exploited. Brines at the Salar de Atacama in Chile also contain boron, but it is not presently extracted. 

The largest uses of platinum group metals in electronics are ruthenium for resistors and palladium for multilayer capacitors, both applied by thick film techniques . Most anodes for brine electrolysis are coated with mixed ruthenium and titanium oxide by thermal decomposition . Chemical vapour deposition of ruthenium was patented for use on cutting tools . 

A fluid loss additive for hard brine environments has been developed [1685], which consists of hydrocarbon, an anionic surfactant, an alcohol, a sulfonated asphalt, a biopolymer, and optionally an organophilic clay, a copolymer of N-vinyl-2-pyrrolidone and sodium-2-acrylamido-2-methylpropane sulfonate. Methylene-bis-acrylamide can be used as a crosslinker [1398]. Crosslinking imparts thermal stability and resistance to alkaline hydrolysis. 

This project placed encapsulated spent fuel elements from an experimental AEG reactor into storage holes drilled into the floor of the mine located in a salt bed. Valuable experimental information was obtained about the interaction between the waste form and the salt in which the waste was emplaced. It was in fact this experiment, conducted in 1968, which revealed that inclusions of moisture, or brine, in the salt beds have a tendency to migrate up a thermal gradient towards a heat source placed in the salt. Quantities of brine were measured as migrating to the deposited waste canisters and the interaction of this brine with the canis-tered material was observed. 

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