The last of the 111 modules used to build the two trains was installed earlier this week. Train 1 comprises 82 modules while Train 2 comprises 29.

Santos GLNG general manager downstream operations Brenton Hawtin said the construction of such a vital part of the plant often referred to as "the big fridge" was a key milestone for the project for Santos GLNG, which is a joint venture between Santos, Petronas, Total and Kogas.

Bechtel is constructing Santos GLNG's two-train LNG plant on Curtis Island.

"LNG trains are essentially big refrigerators that will take natural gas piped from our Queensland gas fields and condense it into liquid form so it can be safely and efficiently shipped," Hawtin said.

"Once we're in full production, these massive pieces of infrastructure will together produce up to 7.8 million tonnes of LNG each year.

"Each module had to be built with a margin of error of only 2mm - which is amazing when you think the heaviest weighed more than 2,500 tonnes and longest stretched nearly 75m."

The modules were constructed in Batangas in the Philippines and shipped to Curtis Island individually.

Hawtin said setting the last module into place was the latest in a series of key milestones across Santos GLNG.

"In the past few weeks, we've put first gas in our pipeline, completed our first major processing hub in our gas fields and finished hydrotesting our second LNG storage tank on Curtis Island," Hawtin said.

Final pipework and cabling on the trains will now take place before commissioning of the plant begins later this year as we look towards first LNG next year.