As one of the cleanest and safest of all energy sources, natural gas continues to be in high demand and remains as a vital component of the world’s energy supply. An estimated 60% of the world’s natural gas is trapped in unviable locations where conventional rigs and pipelines will not make do. This is where a floating LNG facility would play a significant role.
Floating liquefied natural gas, also known as FLNG, is not a new idea. Ever since the 90s, FLNG has been seriously considered by the oil and gas industry as a viable option. However, technological and economical advances can make the idea a reality.
According to the International Energy Agency, the global demand for natural gas could rise by more than half by 2040. Most of these gas resources are located in hard-to-reach areas, posing many technical and economic challenges.
How it Works
Liquefied natural gas (LNG) is methane gas, chilled to -162°C to become a liquid. This liquid then occupies about 1/600 the space of methane in its gaseous form, making it practical to transport. The conventional approach to producing LNG is to pipe the gas over hundreds of kilometres from offshore to an onshore plant to be processed and liquefied. The gas is then stored on site before being offloaded to a LNG tanker to be taken to market.
FLNG describes a method for developing offshore natural gas in which the gas is extracted from the wellhead to the floater. Then, the gas is processed on-board the floater prior to the liquefaction. Only then, the gas is cooled down to shrink the gas volume by 600 times becoming LNG. The LNG is then stored in a dual row membrane type cargo containment system (CCS) before offloading to LNG carriers. The LNG will then be offloaded to a carrier and taken directly to market.
Comparatively, FLNG is better than the conventional LNG method, due to the opportunity to leverage remote areas for gas, increasing these areas’ financial viability. This method also results in less environmental damage due to less piping and factories, leading to less of a carbon footprint. Because the FLNG functions off the land, it eliminates the need for pipes connecting it to the land, saving a lot of money that would otherwise be used for the installation and procurement of needed material.
Acknowledging the Difficulties
There are several technical challenges that relate to hull motion and its effect on process and equipment. The FLNG facility typically must remain moored on location for at least 20 years without returning to the port. It must be designed to operate in extreme weather environments and the rough seas. One of the key design challenges also includes the adaptability of equipment. The equipment will be larger, heavier and some of the units may have tall vertical columns, which calls for modifications before FLNG installation.
Safety is a sensitive subject for FLNG because there is no precedent. A new set of safety considerations is introduced because of its complex design and operation procedures. To further advance the development of FLNG, safety must be focused on to mitigate the risks of LNG production and poor analysis.
Our Own Malaysian Pride
Back home, Malaysia’s very own PETRONAS has successfully developed a FLNG project, PFLNG Satu, the world’s first floating LNG facility. On 5 December 2016, PETRONAS produced the first LNG drop from the PFLNG Satu and delivering its first cargo a few months later.
The PFLNG Satu is rooted at about 180 kilometres offshore of Bintulu, Sarawak and is producing 1.2 million tonnes of LNG per annum. That amount of LNG can be used to generate 100,000 kilowatt per day. With a design life of 20 years, the PFLNG Satu can be redeployed to other fields as they deplete. This is one big reason PETRONAS opted for FLNG, as it results in more value for money and makes once unreachable places a viable source of resources.
Other oil and gas companies such as Shell and Japan’s Inpex Corp. also have taken great strides in delivering their first FLNG project. Both are targeting gas from a connected reservoir in Australia’s remote Browse Basin, about 200 kilometres off its northwest coast. These FLNG projects allow for access to gas reserves in remote and stranded fields which are otherwise deemed economically unfeasible.
The industry has risen to the technical challenges with risks have been mitigated, allowing the first FLNG projects to be commissioned. Pushing the boundaries of technology and innovation, this technological marvel changed the landscape of LNG production in not only Malaysia but globally as well.
