Monday, October 22 2018

VietNamNews

Water from thin air

Update: September, 23/2018 - 09:00
Magic device: Associate Professor Lê Văn Lữ (left), one of the researchers, gets water from the device.
Viet Nam News

Hard times bring new and clever ideas.

After there was little rain in the Mekong Delta, farmers found it difficult to find water after digging underground.

Scientists then came up with a plan.

That was to get water from the air.

Khánh Dương

HÀ NỘI – Coffee farmers in the southern central province of Ninh Thuận used to dig up to 40 metres underground to reach water in order to irrigate their crops during droughts.

Now when the land dries up, they struggle to find water at depths of even 100m.

The water shortage has devastated residents of drought-plagued localities in Việt Nam, especially the Mekong Delta region, in recent years. Their lives and livelihoods have come to a standstill.

Yet from difficulty emerges wisdom.

“Water is in short supply, even underground. So, where can we make water from?”

 “Why not from the air?”

A group of researchers from HCM City’s University of Natural Resources and Environment and the University of Technology were asking this very question, and now have finally come up with an answer.

After two years of research since 2016, the scientists have developed a device which extracts water from humid air.

Their innovation is based on a simple physical rule – humidity will condense in conditions of exceedingly high humidity.

The system cools the air below its dew point at which water condensation starts. Then the water is purified, mineralised, sterilised and becomes drinking water.

The so-called water harvester is able to pull up to 100 litres of water out of the air over a period of eight to nine hours depending on the device’s capacity.

Technology to extract water from the air is not new and has been applied in the Sahara desert. But this invention is a first for Việt Nam, said Professor Phan Đình Tuấn, rector of HCM City’s University of Natural Resources and Environment.

The researchers also thought about how to make use of solar energy in dry areas. Solar panels, a renewable energy solution being promoted in Việt Nam, have been installed and connected with the water harvester to run the extracting system. It is considered a suitable solution to power the devices in remote areas without access to the grid.

Water extracting machines powered by the sun are hoped to be applied in remote disadvantaged regions around the country, said Prof Tuấn.

Two such devices have trialled so far and are successful in saving drought-hit residents.

The first device with a daily capacity of 100 litres was placed at the Văn Lâm Primary School in Ninh Thuận’s Phan Rang City, and supplies pure drinking water for 680 students that meets the criteria of the health ministry.

Another device with a smaller capacity (20 litres per day) is placed at HCM City’s University of Natural Resources and Environment where the researchers are working and supplies drinking water for students and lecturers.

Associate Prof Lê Văn Lữ, head of the research team, said: “Extracting water from humid air in Ninh Thuận Province and regions in the Central Highlands is problematic as temperatures are high with very low humidity.”

Prof Tuấn said that the weather, including temperatures and humidity, in drought-hit areas keeps fluctuating due to the impacts of climate change. The research team had to make careful calculations on the parameters of the devices.

"In conditions of low humidity, for example, we had to design the device with a capacity of 15 litres to expect an outcome of 10," he said.

"Luckily, the invention has been welcomed by locals and financially assisted by the Ministry of Natural Resources and Environment and Ministry of Science and Technology within the framework of National Scientific and Technology Programme on Natural Resources, Environment and Climate Change.

“For scientists like us, we find the invention scientifically interesting.”

Aiming high

The water harvester offers hope to farmers and residents in hot and dry condition, as long as it is connected with an energy source.

“It can be used on islands which lack access to fresh water. Solar energy can be replaced by wind power on the islands to run the device,” he said.

Not only for drinking water, the research team has also been looking into using water extracted from the air to irrigate crops in drought-plagued regions.

“In urgent situations where farmers lack water, the device can be used to supply water for withered plants such as coffee and grapes,” Tuấn said.

“Such a valuable device might save crops in the future.”

The research team hopes that the technology will be funded and transferred to companies so that it can be applied in more places.

"The investment needs co-operation between the State and private businesses to bring technology to benefit the community," Tuấn said. – VNS


 

GLOSSARY

Coffee farmers in the southern central province of Ninh Thuận used to dig up to 40 metres underground to reach water in order to irrigate their crops during droughts.

To irrigate means to spray water on to crops.

A drought happens when no rain falls for an unusually long time in an area where there is usually rain.

The water shortage has devastated residents of drought-plagued localities in Việt Nam, especially the Mekong Delta region, in recent years.

If the water shortage devastates people, it ruins them.

Residents of a place are people who live in that place.

Yet from difficulty emerges wisdom.

If wisdom emerges from difficulty, it means that wisdom comes out of difficulty.

A group of researchers from HCM City’s University of Natural Resources and Environment and the University of Technology were asking this very question, and now have finally come up with an answer.

Researchers are people who find things out. They are often academics and scientists.

After two years of research since 2016, the scientists have developed a device which extracts water from humid air.

Extracts means “takes out”.

Air that is humid has lots of water in it.

Their innovation is based on a simple physical rule – humidity will condense in conditions of exceedingly high humidity.

An innovation is an idea that has been turned into action.

If humid air condenses, then water that is in that air will turn into drops of liquid.

Exceedingly means “very, very”.

The system cools the air below its dew point at which water condensation starts.

Dew point is a temperature at which water held in the air turns to liquid.

Then the water is purified, mineralised, sterilised and becomes drinking water.

If water is purified it has all sorts of unhealthy things that are in it, taken out.

If it is mineralised, it has minerals added to it.

If it is sterilised it is boiled so that germs in it are killed.

The so-called water harvester is able to pull up to 100 litres of water out of the air over a period of eight to nine hours depending on the device’s capacity.

A device’s capacity is the amount of work it is able to do.

The researchers also thought about how to make use of solar energy in dry areas.

Solar means to do with the Sun.

Solar panels, a renewable energy solution being promoted in Việt Nam, have been installed and connected with the water harvester to run the extracting system.

Renewable energy is energy that is made in such a way that it does not destroy anything.

A solution is an answer to a problem.

If something is promoted, an effort is made to make people hear about how good it is.

Installed means “put in place”.

It is considered a suitable solution to power the devices in remote areas without access to the grid.

The grid is the network of electricity lines that bring power to houses.

To be able to access the grid means to be able to connect to it to get power.

Water extracting machines powered by the sun are hoped to be applied in remote disadvantaged regions around the country, said Prof Tuấn.

Remote regions are faraway places.

Areas that are disadvantaged have not had much money or other resources spent on them.

Two such devices have trialled so far and are successful in saving drought-hit residents.

If the devices have been trialled, they have been put to test.

The first device with a daily capacity of 100 litres was placed at the Văn Lâm Primary School in Ninh Thuận’s Phan Rang City, and supplies pure drinking water for 680 students that meets the criteria of the health ministry.

Criteria are requirements.

Another device with a smaller capacity (20 litres per day) is placed at HCM City’s University of Natural Resources and Environment where the researchers are working and supplies drinking water for students and lecturers.

Lecturers are teachers at universities and colleges.

Prof Tuấn said that the weather, including temperatures and humidity, in drought-hit areas keeps fluctuating due to the impacts of climate change.

Fluctuating means changing dramatically.

Impacts are effects.

The research team had to make careful calculations on the parameters of the devices.

Calculations are determination of the amount or number of something.

Parameters are statistics.

"Luckily, the invention has been welcomed by locals and financially assisted by the Ministry of Natural Resources and Environment and Ministry of Science and Technology within the framework of National Scientific and Technology Programme on Natural Resources, Environment and Climate Change.

Financially assisted means “helped with money”.

“For scientists like us, we find the invention scientifically interesting.”

An invention is something someone has invested.

The research team hopes that the technology will be funded and transferred to companies so that it can be applied in more places.

Transferred means sent from one place to another.

"The investment needs co-operation between the State and private businesses to bring technology to benefit the community," Tuấn said.

Co-operation means working together.

If something benefits the community, it makes the community stronger.

WORKSHEET

State whether the following sentences are true, or false:

  1. It took two years for the scientists to develop a sevice that extracts water from humid air.
  2. Văn Lâm Primary School is in Phan Rang City.
  3. People grow coffee in the southern central province of Ninh Thuận.
  4. Professor Phan Đình Tuấn, rector of Ha Noi’s University of Natural Resources and Environment.
  5. The water harvester must always be connected to an energy source.

ANSWERS:

© Duncan Guy/Learn the News/ Viet Nam News 2018

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

1. True; 2. True; 3. True; 4. False; 5. True.

 

 

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