Name the process used to obtain drinking water from brine
Answers
Explanation:
Water desalination
Methods
Distillation
Multi-stage flash distillation (MSF)
Multiple-effect distillation (MED)
Vapor-compression (VC)
Ion exchange
Membrane processes
Electrodialysis reversal (EDR)
Reverse osmosis (RO)
Nanofiltration (NF)
Membrane distillation (MD)
Forward osmosis (FO)
Freezing desalination
Geothermal desalination
Solar desalination
Solar humidification–dehumidification (HDH)
Multiple-effect humidification (MEH)
Seawater greenhouse
Methane hydrate crystallization
High grade water recycling
Wave-powered desalination
Desalination is a process that takes away mineral components from saline water. More generally, desalination refers to the removal of salts and minerals from a target substance,[1] as in soil desalination, which is an issue for agriculture.[2]
External audio
audio icon "Making the Deserts Bloom: Harnessing nature to deliver us from drought", Distillations Podcast and transcript, Episode 239, March 19, 2019, Science History Institute
Saltwater (especially sea water) is desalinated to produce water suitable for human consumption or irrigation. The by-product of the desalination process is brine.[3] Desalination is used on many seagoing ships and submarines. Most of the modern interest in desalination is focused on cost-effective provision of fresh water for human use. Along with recycled wastewater, it is one of the few rainfall-independent water sources.[4]
There are approximately 16,000 operational desalination plants, located across 177 countries, which generate an estimated 95 million m3/day of freshwater.[5] Currently, desalination accounts for about one percent of the world’s drinking water.[6] Desalination is particularly prevalent in countries located in the Middle East and North Africa region, such as Saudi Arabia, the UAE, and Kuwait.[5] Desalination is also an important source of water in small island developing states.[5]
Due to its energy consumption, desalinating sea water is generally more costly than fresh water from surface water or groundwater, water recycling and water conservation. However, these alternatives are not always available and depletion of reserves is a critical problem worldwide.[7][8] Desalination processes are usually driven by either thermal (in the case of distillation) or electrical (in the case of reverse osmosis) as the primary energy types.
Currently, approximately 1% of the world's population is dependent on desalinated water to meet daily needs, but the UN expects that 14% of the world's population will encounter water scarcity by 2025.[9] Desalination is particularly relevant in dry countries such as Australia, which traditionally have relied on collecting rainfall behind dams for water.
Kuwait produces a higher proportion of its water through desalination than any other country, totaling 100% of its water use.[10]
Schematic of a multistage flash desalinator
A – steam in B – seawater in C – potable water out
D – brine out (waste) E – condensate out F – heat exchange G – condensation collection (desalinated water)
H – brine heater
The pressure vessel acts as a countercurrent heat exchanger. A vacuum pump lowers the pressure in the vessel to facilitate the evaporation of the heated sea water (brine) which enters the vessel from the right side (darker shades indicate lower temperature). The steam condenses on the pipes on top of the vessel in which the fresh sea water moves from the left to the right.
Plan of a typical reverse osmosis desalination plant