There’s no mistaking the excitement in Frode Helland-Evebo’s voice. Pacific Green Marine Technologies’ Vice President of Marine Direct Sales is in no doubt why he left his previous employer, Clean Marine to join Pacific Green in late summer.
“The technology is groundbreaking,” Frode says. “That’s all there is to it. PGMT’s ENVI-Marine™ system is smaller, more efficient, cheaper to install and costs around 20% less to run than the competition’s. It’s a game-changer. No other scrubber manufacturer can match, never mind beat, our scrubber. It’s the best. Ken has done fantastic work.”
The Ken in question is Ken McClelland, PGT’s Technical Director. He is the inventor of the company’s much-celebrated patented exhaust gas scrubbing methods. And, better than anyone, Ken knows why his marine scrubber design is so revolutionary and game-changing.
It’s all about bubbles
“We actually bought some gas scrubber technology in 2001 but it didn’t work very well,” says Ken.
“The guy who had designed it had made it far too complex. And I had an idea on how to simplify and improve it.”
That idea was all about bubbles, as Ken explains.
“Bubbles are the key to effective scrubbing. And the smaller the bubble, the better. Tiny bubbles, which together actually look more like a froth, have the greatest surface area relationship to volume, so the tinier bubbles you can make the more efficient the process will be. The real function of all these tiny bubbles, the froth, is to create surface contact between whatever flue gas that you're scrubbing and your reagent, which in marine scrubbers is sea water.”
“Let me give you an example. If you had a 100 millimeter cube, which is just one big bubble, you'd have a certain surface area. But if you had a thousand small bubbles, you'd have far more, because there’s more surface area. You'd probably have 5,000 times the surface area.
So, the small bubbles then give better contact with either the acid gases or particulate that you're trying to remove.”
The patented TurboHead™ technology is key to PGT’s technical success. Ken produced the first usable prototype in 2011, though it has evolved continuously with field testing.
“Essentially, it's extremely simple. The flue gas comes from below the head and there are slots in the head which create a certain velocity of gas through the slots. The beauty of the TurboHead™ is its positive contact and there's a lot of energy in the contact.”
Most of the competitors’ scrubbers use spray, and spray is never uniform
By way of example, Ken suggests taking a huge breath and blowing into a straw in a glass of water.
“You’ll see that you can get that water so turbulent that there's a lot of interaction. The width of our slots generates the bubble size that we want and the frequency of the slot generates the right area ratio to get the velocity through the slot for the designed reaction.”
“And then the reagent, sea water with our marine scrubbers, interacts with the gas in the turbulence so all you need to do to remove sulphur (sulfur) is expose it to water. As soon as sulphur and water are in contact, it becomes sulphuric acid. And then you select the right reagent to remove and neutralize whatever contaminate that you want to remove. So in our case, we're after sulphur.”
And it’s this vast number of tiny bubbles and the huge surface area they create that makes the ENVI-Marine™ system so much more efficient than the competition’s.
“The flue gas, the contaminated flue gas, has no way of going around the contact. It has to go through the froth, whereas most of the competitors’ scrubbers use spray, and spray is never uniform. There are areas that may not get coverage. But with the TurboHead the flue gas has no alternate path, so there's direct contact between the flue gas and the reagent. And this makes it much more efficient.”
“We’re offering customers a scenario which is literally ‘win-win’.”
This patented system gives Pacific Green a huge competitive advantage. But it doesn’t stop there. The machinery is more compact and lighter than most other scrubbers, thereby saving shipowners space and fuel.
And Pacific Green has also come up with a unique way to make the world’s best gas scrubbers affordable to all shipowners.
Pacific Green has developed a savings-sharing mechanism, which effectively guarantees a return on investment for owners who elect to install Pacific Green scrubbers on their vessels.
“Our new way of offering scrubbers lets ship operators have visibility on their spending going forward,” says Frode. “We’re offering customers a scenario which is literally ‘win-win’.”
Based on the vessel’s typical operating profile, Pacific Green and the owner agree to a minimum number of tonnes of HFO burned per month.
As 3.5%S HSFO is expected to trade at discount to 0.5%S LSFO, each tonne burned will result in savings to the owner. PGMT and the owner will share the savings for three years, with the owner taking a progressively larger share. After three years, the owner will take 100% of the fuel differential savings.
Pacific Green will guarantee to the owner a minimum differential ($/MT) between 3.5%S HSFO and 0.5%S LSFO for two years. If the actual differential falls below the pre-agreed differential, Pacific Green will compensate the owner for each of the agreed upon number of HSFO tonnes burned per month. This provides a guaranteed revenue floor for the owner.
And if the actual differential is higher than the guaranteed minimum differential, both the owner and Pacific Green will benefit as a result of the increased savings.
The mechanism is brilliantly simple. And a relatively small initial payment from the owner will secure the agreement. Pacific Green will pay for all remaining costs, including the 3D scanning, engineering, equipment supply, installation, and commissioning and sea-trials.
Frode is understandably very pleased with this savings-sharing mechanism. “The shipowner gets a scrubber that will probably pay for itself within the year. And we have another customer enjoying the benefits of using the best gas scrubber on the market.”