Friday is here, and the 'A Taste of Science for the Weekend' corner is back — number 88.
This time: why the global food supply depends on natural gas, and what makes the process of transporting it so fascinating.
-
Natural gas is composed mainly of methane — a molecule made of one carbon atom and four hydrogen atoms.
It forms through the compression and decomposition of plant and animal remains deep underground, and is extracted by drilling.
The gas that comes out of the ground contains various impurities, such as hydrogen sulfide, which can rapidly corrode the pipelines used to transport it. It therefore must be thoroughly refined through various processes to obtain methane that is as pure as possible.
The gas can be transported over long distances via pipelines, but sometimes it needs to be shipped across especially great distances or routed around hostile countries — so it undergoes a process that converts it into a liquid that can be stored in tanks aboard ships.
-
Methane becomes a liquid only at −161.5 degrees, so it must be cooled progressively using gas-based systems, similar in principle to how a household refrigerator works.
The liquefied gas is placed in well-insulated tanks that keep it at this temperature so it doesn't revert to a gaseous state.
Designing these tanks is a complex engineering and physics challenge: the ship's motion combined with such extremely low temperatures can cause an ordinary metal tank to crack rapidly.
One solution is to use spherical tanks (as seen in the video), which distribute the load evenly across the tank's inner surface.
Today, tanks with a high manganese content are increasingly used, as they have proven to be especially resistant compared to other alloys.
-
Although natural gas is familiar to everyone as a fuel for power plants, cooking, and water heating, it also serves other critical purposes.
Ammonia is an essential raw material for the fertilizer industry — and it is thanks to ammonia that we have enough food to feed the world's population today.
To produce ammonia, hydrogen and nitrogen react with each other in oxygen-free vessels under very high pressure and temperature, and the hydrogen required for this process is obtained by breaking down natural gas.
In the plastics industry, ethane is extracted from natural gas and used to produce ethylene — the building block of polymers for plastic manufacturing.
One of the more intriguing promises of natural gas is pyrolysis.
In this process, natural gas is heated to high temperatures in the absence of oxygen until it breaks down into pure hydrogen and solid carbon. Pure hydrogen is a promising fuel because it produces no pollution, and solid carbon is an important raw material in the battery industry.
-
The closure of the Strait of Hormuz and the shutdown of Qatar's natural gas facilities pose a genuine threat to countries around the world, forcing various nations to once again purchase natural gas from Russia.
It seems that the critical need for gas will serve as a significant catalyst for resolving the crisis and restoring supply, and the world's nations will do whatever it takes to make that happen.
Shabbat Shalom 😊
Video credit: Wendover Productions
--
If you enjoy this corner, you're welcome to follow along and catch it again next week.
#ATasteOfScienceForTheWeekend