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Marine Propulsion & Auxiliary Machinery

Marine Propulsion & Auxiliary Machinery

Water in fuel? The ‘crazy’ solution to reduce NOx

Mon 30 Apr 2018 by Jamey Bergman

Water in fuel? The ‘crazy’ solution to reduce NOx
Kaisa Honkanen: We can reduce NOx down to 20 percent

It's not uncommon for Blue Ocean Solutions’ Kaisa Honkanen to receive a look of incredulity when she explains the technology behind her company’s nitrous oxide (NOx) reduction solution.

“As crazy as it sounds, yes, we add water into the fuel, and we create this homogeneous mix. This is not something new. This has been used for decades, and the main reason has been to reduce NOx,” she told the Sulphur Cap 2020 Conference in Amsterdam.

“It’s pretty straightforward. You add water, you cool the combustion temperature, and therefore the NOx goes down.”

Ms Honkanen said Blue Ocean Solutions’ focus since the group began developing its technology in 2011 has been on increasing the fuel atomisation to improve the fuel spray, which ultimately reduces costs.

“When it comes to the 2020 0.5% sulphur cap, one thing I can say for sure is the increase in cost will be inevitable – whether it’s capex or opex,” she said.

“There is a lot of uncertainty … and it seems that the industry is not prepared at all for the sulphur cap. It’s like everyone is looking at each other. Refineries – shipowners, shipowners – refineries. A lot of uncertainty.”

“There are options, but they all come with different challenges. You can switch to compliant fuel, but that comes with expected operational costs,” she said.

“There’s LNG, methanol, onboard desulphurisation … but they all come with a cost, and I am sure the 2019 ballast water system [mandate] will not help the cash-flow situation either.”

Ms Honkanen estimated that the shipping sector will face US$24Bn to US$60Bn in annual spending to meet new regulations. Owners can find the best solution for their businesses, she said, but they cannot escape the increase in cost.

Citing a case study outlining how her company's technology can help mitigate this expected cost increase, she noted that having the optimal emulsion of water to fuel is key.

“It is 10%. That is the optimum amount,” she said, adding, “the characteristics of the water [molecules] is important as well. They have to be between two to eight microns.”

Ms Honkanen said her company does not use any chemical additives to keep costs down.

So why add the water?

“We can [reduce NOx] down to 20%,” she said.

The water also has a cleaning effect, she said, offering cleaner exhaust, less particulate matter and less soot and complementing scrubbers very well.

There are also cost savings, due to increased fuel efficiency.

“We have consistent [fuel] savings of between 2% to 5%,” she said.

 “Our focus is fuel efficiency, and the way we improve the efficiency is we have the water in fuel; when it is injected into the combustion chamber it explodes. That explosive effect breaks the fuel into smaller droplets, and therefore we get a more complete combustion.”

APL has installed the system on 11 ships to date and a case study on an American President Line ship showed the potential for savings.

“From a year of consecutive data, at 36% utilisation per year, the average cost savings was 3.8%, meaning a US$108,150 savings,” she said.

That equates to a potential for US$2.1M in savings with 80% usage on nine ships, says Honkanen.

Returning to the 2020 sulphur cap, Ms Honkanen said that it is important that her group can emulsify water into HFO and also MGO.

“We expect that, especially with MGO, low-sulphur fuel, the cap will be even higher, so the savings will be higher, as well,” she said.

 “Every drop matters, both in terms of the bottom line and the environment.”

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