Home Today's Paper Most Popular Video Gallery Photo Gallery
Subscription Blog Signin Register
Logo
Tuesday, July 23, 2019 10:48:43 PM
Follow Us On: Facebook Twitter Twitter Twitter Twitter

Fresh water security

It needs a cost-effective technical solution

By
07th-Apr-2019       
Comments
Share your thought
Post a comment »
Read all () »

Shishir Reza :
Globally half a billion people know, how water insufficiency in a year circle. For 1.5 to 2 billion people, water resources are unsatisfactory to assemble demands for at least a part of the year. Desalination technologies can provide an unrestricted, climate sovereign and fixed supply of high quality water, chiefly used by the community and industrial sectors. In particular, desalination is a vital technology in the Middle East and for tiny island nations which typically lack renewable water resources.
Nowadays almost 16,000 desalination plants are in operation in 177 countries, producing 95 million cubic meters of freshwater every day. Falling economic costs of desalination and the development in membrane technologies, particularly reverse osmosis, have made desalination a cost-competitive and attractive source of freshwater around the globe.
The increase in desalination has been driven by intensifying water scarcity due to rising water demands associated with population growth, increased water consumption per capita, and economic growth, coupled with diminishing water supplies due to climate change and contamination.
The most complete ever compiled - to revise the world's badly outdated statistics on desalination plants. Most startling was our finding that the volume of hyper saline brine produced overall is about 50% more than previously estimated.
Globally, plants now discharge 142 million cubic meters of hyper saline brine every day - enough in a single year to cover Florida under 1 foot of brine. Considered another way, the data shows that for every unit of freshwater output, desalination plants produce on average 1.5 units of brine.
Some two-thirds of desalination plants are in high-income countries, with capacity concentrated in the Middle East and North Africa. And over half - 55% - of global brine is produced in just four countries: Saudi Arabia (22%), UAE (20.2%), Kuwait (6.6%) and Qatar (5.8%).
Middle Eastern plants, which largely operate using seawater and thermal desalination technologies, typically produce 4 times as much brine per cubic meter of clean water as plants where river water membrane processes dominate. Brine disposal methods, meanwhile, are largely dictated by geography but traditionally include direct discharge into oceans, surface water or sewers, deep well injection and brine evaporation ponds.
Desalination plants near the ocean (almost 80% of brine is produced within 10km of a coastline) most often discharge untreated waste brine directly back into the marine environment. Brine raises the salinity of the receiving seawater, and brine underflows deplete dissolved oxygen needed to sustain life in the marine environment.
This high salinity and reduced levels of dissolved oxygen can have profound impacts on marine ecosystems and organisms, especially those living on the seafloor, which can translate into ecological effects observable throughout the food chain. Furthermore, the oceans are polluted with toxic chemicals used as anti-scalants and anti-foulants in the desalination process.
There is a clear need for improved brine management strategies to meet this rising challenge. This is particularly important in countries producing large volumes of brine with relatively low efficiencies, such as Saudi Arabia, UAE, Kuwait and Qatar.
In fact, we can convert this environmental problem into an economic opportunity. Brine has many potential uses, offering commercial, social and environmental gains. It has been used for aquaculture, with increases in fish biomass of 300% achieved.
It has also been successfully used to irrigate salt tolerant species, to cultivate the dietary supplement to generate electricity, and to irrigate forage shrubs and crops. With improved technologies, a large number of metals, salt and other minerals in desalination plant effluent could be mined.
These include sodium, magnesium, calcium, potassium, bromine, boron, strontium, lithium, rubidium and uranium, all used by industry, in products, and in agriculture. The needed technologies are immature, however; recovery of these resources is economically uncompetitive today.
Research and ideas related to a variety of unconventional water sources scaled up to meet the even superior deficit in freshwater supplies looming in much of the world. In particular, we need to make desalination technologies more reasonable and enlarge them to low-income and lower-middle income countries like Bangladesh.
Costs are falling from continued improvements in energy recovery systems and the coupling of desalination plants. At the same time, we have to address potentially severe downsides of desalination - the harm of chemical pollution to the marine environment and public health.

(Shishir Reza, an Environmental Analyst & Associate Member of Bangladesh Economic Association)

Tariff
Add Rate

News Archive

Inside The New Nation

Editorial »

Stand beside flood-hit people


DIFFERENT kinds of waterborne diseases have begun spreading as floodwater started receding across the country. But in the post-flood scenario, many people are suffering from diarrhoea, skin diseases, dysentery, cholera and other waterborne diseases. Officials of the Flood Forecasting and Warning Centre said the flood situation may continue improving in ...

Sports »

Lowry weathers storm to win British Open and first major


Ireland's Shane Lowry withstood howling wind and rain to win his first major at the British Open by six shots from Tommy Fleetwood on Sunday, describing the achievement as "an out-of-body experience".In desperately difficult conditions, Lowry's one-over par final round was still more than enough as he finished on 15-under ...

International »

UK leadership favourite Johnson hits more turmoil on last voting day


AFP :Britain's leadership contest entered its finale Monday with the favourite Boris Johnson facing more defections from ministers over his Brexit plan.The month-long contest between former London mayor Johnson and Foreign Secretary Jeremy Hunt is being decided by fewer than 200,000 grassroots members of the governing Conservative Party.The winner will ...

International »

Zelensky party heads for absolute majority in Ukraine


AFP :Ukraine's comedian-turned-president Volodymyr Zelensky is set to control an absolute majority in parliament, ushering in a generational shift in the ex-Soviet country's political arena.The 41-year-old became Ukraine's youngest ever post-Soviet leader when he took office two months ago and has promised to stamp out corruption and end a separatist ...

City »

Prime Minister Sheikh Hasina presenting National Fisheries Award to Mostofa Al Rajib, Upazila Fisheries Officer, Betagi , Barguna for the latter's contribution in Fisheries Sector at a ceremony held recently in the auditorium of Krishibid Institution, Bangladesh in the city on the occasion of National Fisheries Week.


Entertainment »

Mamo under Tauquir’s direction, Bipasha’s story


Sheikh Arif Bulbon :As an actress, in the beginning of her career, Zakia Bari Mamo got the National Film Award to act in Tauquir Ahmed-directed movie Daruchini Dwip. For this reason, Mamo always respects to Tauquir Ahmed. Now she is a matured actress who always wants to work in challenging ...

Editorial »

Taking law in own hand is an ominous sign


MOBS beat to death five people, including two women, and injured 10 others on suspicion of being child kidnappers across the country on Saturday. The incidents happened just a day after three people were beaten by a mob in Thakurgaon. Incidents of mob beating have increased even after the Bridges ...

International »

Abe on course to retain majority in upper house election


AFP, Tokyo :Japanese voters cast ballots Sunday in an upper house election, with Shinzo Abe's ruling bloc looking to protect its majority and keep on track plans to amend the country's pacifist constitution.The 64-year-old Abe, who is on course to become Japan's longest-serving prime minister, is also hoping to shore ...

Entertainment »

Mehazabien, Tawsif, Sabila Nur’s Eid drama Better half


Entertainment Report :Few days ago, a drama titled Swapno Dekhi Abaro, directed by Mahmudur Rahman Himi, was made with theme given by popular TV actress Mehazabien Chowdhury. Mehazabien also acted in this play against Shamol Mawla which will be telecasted in upcoming Eid. This time Imraul Rafat has made an ...

Editorial »

Administrative control over ACC only to happy the corrupts


ANTI-GRAFT campaigner Transparency International Bangladesh (TIB) has expressed deep concern and extreme disappointment over the government's decision for making Deputy Commissioners as authorised officers to oversee the Anti-Corruption Commission's work in the districts. The move will undoubtedly restrict the ACC's ability to fight graft and proper investigation into allegations of ...

Sports »

Penny drops for Canada's teen swim queen Oleksiak


Canada's Penny Oleksiak insists she has finally left the "weirdness" of capturing Olympic swimming gold at the tender age of 16 after finally recovering from a lengthy Rio hangover. Oleksiak, who is preparing for the world championships which begin in South Korea this weekend, stunned the sport when she dead-heated ...

International »

Thousands rally in support of Hong Kong police


AP, Hong Kong :Tens of thousands of people rallied in support of Hong Kong's police and pro-Beijing leadership on Saturday, a vivid illustration of the polarisation coursing through the city after weeks of anti-government demonstrations.Hong Kong has been rocked by more than a month of huge and largely peaceful protests-as ...

International »

US offers $7m to find Hezbollah agent as Pompeo visits Argentina


AFP, Buenos Aires :The United States on Friday offered a $7 million reward to find a Hezbollah operative accused of masterminding a deadly 1994 attack on a Jewish center in Buenos Aires, as Secretary of State Mike Pompeo sought to unite Latin American nations against the militants.Pompeo visited to mark ...

Entertainment »

Shilpa Shetty to return to the big screen after twelve years


Shilpa Shetty is all set to make a comeback on the big screen after a gap of twelve years. The actress was last seen in Dharmendra, Sunny and Bobby Deol starrer Apne (2007). Before jetting off on a holiday with family, Shilpa has green lit filmmaker Aziz Mirza's son Haroon ...

Editorial »

Corruption in WASA crosses all limits


THE Anti Corruption Commission has identified eight projects and three areas in Dhaka WASA where corruption takes place. The State enterprise keeps extending deadlines and increasing the costs of its projects to create room for corruption. In many cases, WASA did not carry out its work as per project designs ...

 
Items that you save may be read at any time on your computer, iPad, iPhone or Android devices.
 
Are you new to our website? Do you have already an account at our website?
Create An Account Log in here
Email this news to a friend or like someone
Email:
Write a comment to this news