Small Change, Big Effect: How A New Gas Turbine Is Helping Fuel Vietnam’s Economic Boom

Thirty years ago, Vietnam was in a deep economic crisis. Still struggling to recover from the war, much of the country was living in abject poverty. It wasn't unusual to walk into a home and find people without electricity. Hyperinflation of 775 percent meant that people had to wait in long lines and bring piles of money to pay for even the most basic goods.

Around that same time, Vietsovpetro, a joint venture between Vietnam and Russia, built a gas platform 100 kilometers off the shores of Vietnam. Located on top of an undersea natural gas field, the platform has pulled gas from 100 meters below the waves ever since helping to fuel an economic renaissance in Vietnam. Today Vietnam is one of the fastest-growing economies in Asia - 99 percent of the country has power and demand for electricity is rising by 11 percent per year.

But for the most part, Vietsovpetro's platform is still operating with aging equipment. That hasn't been a problem until recently, when the company discovered extra pockets of gas near their platform. Vietsovpetro had three choices for how to handle the discovery: continue pumping gas at the same rate, extend the platform to allow for increased capacity or make the existing platform more efficient so it could pump a greater volume of gas without growing its footprint.

Vietsovpetro knew they wanted to increase capacity but they were worried about the cost and time needed to make the platform bigger.

'If they were feeding gas to one power station before, now they could pump at a higher rate or send gas to a new power plant - wherever that gas could be utilized,' says Khurram Majeed, vice president for turbomachinery and process solutions APAC at Baker Hughes, a GE company. 'We looked at the space and we saw we could fit our equipment in so they wouldn't have to extend the platform.'

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Above: 3D printer working at a BHGE plant in Talamona, Italy. Image credit: BHGE. Top: Vietnam needs energy to fuel its economic revival. Image credit: Shutterstock.

BHGE's secret weapon was the NovaLT16 gas turbine. Engineers were able to snugly fit the turbine onto the existing platform to increase the amount of gas flowing from the platform to the mainland.

The turbine helps by powering a compressor that increases the pressure of the gas as it enters the pipeline to shore. The high-pressure compressed gas moves faster and more smoothly. That means that Vietsovpetro can move more gas in a shorter time, helping to fuel new growth in Vietnam.

This is the first time one of these turbines will be installed on an offshore platform, and Vietsovpetro found it a particularly good fit because of its efficiency. Built and designed in Florence, Italy, partially with 3D-printed parts, the turbine can run for four years before it needs to be taken offline for maintenance. The gas engine that was previously powering the compressor on the platform had to undergo maintenance roughly once a year, a process that can cost valuable time and money.

'Inside a gas turbine, all the metal is continually exposed to high pressure and temperatures,' says Majeed. 'Hence the need for shutting it down for maintenance so often. But if you can improve the metallurgy of the parts and the overall design, you can increase the time between maintenance.'

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This 3D-printed gas turbine swirler pushes the fuel mix into the burner. Image credit: BHGE.

The turbine is superefficient and consumes less fuel to generate the same output power as the next-best turbine on the market, with 37 percent mechanical efficiency, compared to the industry average of 36.2 percent.

The NovaLT16 also features 3D-printed parts. Manufactured in GE Additive's facility in picturesque Talamona, Italy, near the northern tip of Lake Como, the turbine's swirler is a deceptively important part of the turbine. Just 4 inches in diameter with blades on the inside, the swirler burns a mixture of fuel and air to power the turbine. Small changes in the shape of the blade can bring large fuel savings. Engineers at Talamona were able to use the quick prototyping capabilities of additive manufacturing to experiment with different small changes to make the swirler as efficient as possible.

They then constructed the part using laser-powered printers called direct metal laser melting machines, which break down CAD files and create the piece as one part, using lasers to fuse one fine layer of metal powder after another in the right design pattern.

It's a tiny part, but for the people of Vietnam, it's making a huge difference as they benefit from the economic boom being helped along by Vietsovpetro's gas platform.