NUS team invents ‘fast and safe’ way to convert natural gas to solid form, says method can boost energy security
SINGAPORE: A team of researchers from the National University of Singapore (NUS) has developed a new mixture that can convert natural gas into solid form within 15 minutes, making it easier to transport and store the gas in a “fast and safe” way.
This could help “enhance” Singapore’s energy security in the long run, said the university.
Singapore is mostly reliant on natural gas - considered the least polluting fossil fuel - for its energy needs.
Currently, ways of storing natural gas include liquefying it at about -160 degrees Celsius or compressing it to almost 250 times atmospheric pressure, said NUS, noting that it can be a challenge to store the gas safely and affordably.
It added that these approaches do not work at a large scale because they are either expensive or not so safe to store for long periods.
To address the challenges, the NUS team formulated a “novel, low-toxicity additive mixture” which speeds up the conversion of natural gas into a non-explosive solid form, said the university in a press release.
“The conversion can be completed in just 15 minutes - the fastest time so far,” it added.
Led by Associate Professor Praveen Linga from the NUS Faculty of Engineering, researchers are now aiming to convert larger volumes of gas into smaller volumes of solid at a pilot scale of 100kg per day.
If successful, this will enable the commercial adoption of the solidified natural gas technology and create a solid that is stable to store at atmospheric pressure, said NUS. Researchers hope to eventually scale it up for industrial use.
“This is especially relevant to natural gas importing countries like Singapore, where 95 per cent of electricity is generated using natural gas,” said Assoc Prof Linga who is from the department of chemical and biomolecular engineering.
“The development of such gas storage technologies would help enhance the country’s energy security.”
Traditionally, most of Singapore’s supply of natural gas comes in gas form through pipelines from Indonesia and Malaysia.
Since May 2013, Singapore has been importing liquefied natural gas (LNG) to diversify and secure its energy sources. The country’s LNG Terminal currently has four storage tanks which can hold 800,000 cubic metres of LNG.
“Our breakthrough can really be put into perspective when you consider that it takes millions and millions of years for gas hydrates to form in nature, yet with our correct addition of secret ingredients to the system in small quantities, the same process can be effected in the laboratory in a matter of minutes,” said research fellow Dr Gaurav Bhattacharjee, who worked on the project.
The new additive mixture contains L-tryptophan, an essential amino acid in diets. This amino acid can also “greatly speed up” the “caging” of natural gas into solid hydrate, which is also known as combustible ice, said NUS.
According to the university, the formulation done by the team produces the quickest reaction rate to date - more than twice as fast as existing standards - while being less toxic and safer to handle.
While other researchers have managed to speed this reaction up artificially in the past, they resorted to using “highly toxic additives” which are unsafe for both the environment and personnel involved, NUS added.
The research was partly funded under the Energy Innovation Research Programme, which is administered by the Energy Market Authority and funded by the National Research Foundation.