Low-sulphur diesel fuel - will there be any difference?

[cruising cockroach]

The cruise line operating my next cruise (two really) claimed to have gone with the exclusive use of low-sulphur marine diesel (no bunker oil) as of the beginning of this year, and not just low-sulphur (0.5% or less) as mandated starting next year but ultra low (0.1% or less).  Just wondering if one will notice any difference, as in lower particulates, haze or soot?

 

Hoping chengkp75 will weigh in.

[chengkp75]

Well, all cruise lines must use low sulfur diesel fuel (0.1%) or a scrubber when in the North American ECA anyway, and this has been the case for the last 3 years.  If you mean they won't use low sulfur residual fuel outside an ECA, then that is a different thing.  Will a passenger notice any difference?  Have you noticed any difference when on a cruise within 200 miles of the North American shore (including PR and the USVI), compared to other areas of the Caribbean (Western or Southern areas that are outside the ECA)?  Have you noticed any difference when in the North Sea or the Baltic?  These areas have mandated low sulfur fuel for years.  Particulates will definitely be less, but will you notice any difference?  Probably not, and haze is difficult to determine whether it is from incomplete combustion or from water vapor from low exhaust temperatures.  Soot is lessened using diesel fuel, but it still forms on turbocharger blades and boiler tubes, and still needs to be cleaned off these surfaces to maximize heat transfer, and the end result of this cleaning is the soot that plagues some aft areas of cruise ships.  The boiler tubes are cleaned using steam to blast the soot off the tubes, and this creates the slightly wet soot flakes.  The turbochargers are cleaned either using water (which flashes to steam due to the heat in the turbocharger) or ground walnut shells (about 1-2mm size) that produce drier soot flakes and small burnt "chunks" of shell.

 

Where you will see the difference is in cruise prices, as low sulfur diesel fuel costs $592/metric ton today in Houston, while residual fuel costs $380/metric ton, or 55% more than residual fuel, and then you need to add in the lower specific energy of diesel fuel (about 10% less) than residual fuel, so you need to burn more diesel to get the same energy as residual fuel.

[cruising cockroach]

Of all the places you've listed where LS fuel mandate was in effect in that time frame, only off Alaska (pretty much too cold to spend any time outside other than in the hot tub, and for that cruise, no attraction to spend time aft or downwind of the funnel).  Ship was the Celebrity Millennium so no piston engines as it has gas turbines.  Did cruise up from Los Angeles to Vancouver in earlier 2016 on the Star Princess but again, did not spend much time downwind of the funnel.  Not sure if the low-sulphur mandate was in effect but I did notice a brown plume.  IIRC, I thought you might have mentioned - in reply to something I might have asked re: low-sulphur fuels at the time - that scrubbers work well in the lab but not such much in actual conditions and usage at sea?

 

The cruise line (Ponant) claims it's using low sulphur marine diesel only on a worldwide basis as of the beginning of the year (fares are high enough).

 

I do remember huge flakes of oily soot landing on the aft decks of HAL's Zaandam when headed down the west coasts of the Americas though.  That was in late 2014.  Did notice the walnut shells on the container ship in early 2016.

 

The ship on the upcoming cruise is small (not even 11,000 tons) and the only pool is at the aft, and not to far below the smoke stack.

Edited January 23, 2019 by cruising cockroach

[Heidi13]

I figure you have done a few trips on the ferries between Swartz Bay & Tsawwassen. They never used bunker fuel, as since I started back in 81, it was always Diesel. Last few years it was low sulphur.

 

We rarely had any soot, worst offender was the coal dust from Delta Port.

[cruising cockroach]

11 hours ago, Heidi13 said:

I figure you have done a few trips on the ferries between Swartz Bay & Tsawwassen. They never used bunker fuel, as since I started back in 81, it was always Diesel. Last few years it was low sulphur.

 

We rarely had any soot, worst offender was the coal dust from Delta Port.

 

I see there's still a (less) discernible plume but I guess no getting around until the ships are all fuelled by LNG, if that ever comes to past.

 

Yes, coal dust from the terminal is bad despite what the port says.  Did a brief house sit just off the west coast side of Tsawwassen 2 short blocks from the boundary for ~2 weeks.  Amount of dust accumulating on the outdoor part of the house in less than a week was... disturbing.

[Heidi13]

41 minutes ago, cruising cockroach said:

 

I see there's still a (less) discernible plume but I guess no getting around until the ships are all fuelled by LNG, if that ever comes to past.

 

Yes, coal dust from the terminal is bad despite what the port says.  Did a brief house sit just off the west coast side of Tsawwassen 2 short blocks from the boundary for ~2 weeks.  Amount of dust accumulating on the outdoor part of the house in less than a week was... disturbing.

If you are crossing to Tsawwassen, check out the Spirit of BC, which was converted to LNG last year. The Spirit of VI will also be running on LNG with it returns for the summer. They do also use small amounts of diesel, but it's many years since I researched the operation using LNG. Hopefully Cheng can clarify.

 

With sitting at Tsawwassen overnight, the port side ventilation intake filters were all full of coal dust, which was worse in the summer months with the prevailing NW winds.

[chengkp75]

Even using LNG, there will be some soot, and some "plume" as LNG is just another hydrocarbon, and incomplete combustion will still produce carbon and carbon salts.

 

LNG operation in marine diesels is done via "dual fuel" engines, engines that can burn either liquid or gaseous fuels, or both.  They can typically handle a range of mixtures from 100% liquid fuel (diesel, residual, or even crude oil) to 95% gaseous.  The reason you can't go to 100% LNG is that the flash point of LNG is too high, and a "compression ignition engine" (diesel) doesn't get the air/fuel mixture hot enough to ignite, so you need a spark plug.  To eliminate the spark plug, about 5% diesel fuel is injected with the LNG to start the combustion rolling.  LNG ships, including all the new LNG powered cruise ships will have substantial diesel fuel storage as well, as part of the Safe Return to Port requirements requiring a backup fuel system.  Ships can vary the ratio of LNG to liquid fuel depending on emission requirements and relative fuel costs.

[cruising cockroach]

4 hours ago, Heidi13 said:

If you are crossing to Tsawwassen, check out the Spirit of BC, which was converted to LNG last year. The Spirit of VI will also be running on LNG with it returns for the summer. They do also use small amounts of diesel, but it's many years since I researched the operation using LNG. Hopefully Cheng can clarify.

 

Didn't know the Spirit ships were being converted (just know the new Polish-build ships are LNG-fuelled), and I haven't been on one for a while (last rides were on Coastal ships, and I remember because the ship didn't have to turn around at both ends), and which berth it uses at Swartz Bay.

[cruising cockroach]

3 hours ago, chengkp75 said:

Even using LNG, there will be some soot, and some "plume" as LNG is just another hydrocarbon, and incomplete combustion will still produce carbon and carbon salts.

 

LNG operation in marine diesels is done via "dual fuel" engines, engines that can burn either liquid or gaseous fuels, or both.  They can typically handle a range of mixtures from 100% liquid fuel (diesel, residual, or even crude oil) to 95% gaseous.  The reason you can't go to 100% LNG is that the flash point of LNG is too high, and a "compression ignition engine" (diesel) doesn't get the air/fuel mixture hot enough to ignite, so you need a spark plug.  To eliminate the spark plug, about 5% diesel fuel is injected with the LNG to start the combustion rolling.  LNG ships, including all the new LNG powered cruise ships will have substantial diesel fuel storage as well, as part of the Safe Return to Port requirements requiring a backup fuel system.  Ships can vary the ratio of LNG to liquid fuel depending on emission requirements and relative fuel costs.

 

Thanks for the explanation.   Looks like it is the IC process that is inherently faulty with incomplete combustion.  I was thinking a gas would ignite and combust more completely than a vaporised liquid.

 

I imagine most modern cruise ships should have somewhat more-complete combustion as the oil-burning engines are 4 stroke (vs 2 stroke on direct-drive engines found on cargo ships)?  I was hoping the particulate matter emission would be reduced with diesel as I understand the particulate counts downstream of the funnel is extremely and unhealthily high if using bunker fuel (is there a requirement to use diesel in the Mediterranean?).  Yes, I do realise particulate (and other) emission from 4-stroke diesel vehicles is still high despite use of chemical catalysts, which is why the EU aims to ban them eventually.

[chengkp75]

1 hour ago, cruising cockroach said:

 

Thanks for the explanation.   Looks like it is the IC process that is inherently faulty with incomplete combustion.  I was thinking a gas would ignite and combust more completely than a vaporised liquid.

 

I imagine most modern cruise ships should have somewhat more-complete combustion as the oil-burning engines are 4 stroke (vs 2 stroke on direct-drive engines found on cargo ships)?  I was hoping the particulate matter emission would be reduced with diesel as I understand the particulate counts downstream of the funnel is extremely and unhealthily high if using bunker fuel (is there a requirement to use diesel in the Mediterranean?).  Yes, I do realise particulate (and other) emission from 4-stroke diesel vehicles is still high despite use of chemical catalysts, which is why the EU aims to ban them eventually.

Well, there is a vast difference between two stroke engines on land and two stroke marine engines.  Two stroke marine engines are typically of the "long stroke", or "super long stroke" variety (up to 2.5 meters or 8.4 feet), and they turn at a relatively sedate 125rpm or less, so there is a very long time for combustion to happen inside the cylinder, compared to the small high revving two strokes on land (lawn mowers, etc).  Actually, the higher revving 4 stroke engines on cruise ships are more prone to incomplete combustion than the two stroke engines.

 

Yes, particulate is reduced using lighter fuels, diesel and LNG, but not completely removed, but use of residual fuel does not produce "unhealthy" levels of particulates, despite efforts by environmental groups to portray this as the case.  Most of those articles have a data set of one ship, and one day, and don't mention the prevailing environmental conditions (wind, humidity, etc) at the time they took their readings.

 

Don't know of any ship that uses chemical catalysts for exhaust emission control, a scrubber is basically a sprinkler that wets down the particulate matter, and combines with some byproducts to produce acids (sulfur dioxide in exhaust gas will combine with water to form sulfuric acid), so scrubber water will have an alkali additive to prevent corrosion to the exhaust system.  The chemicals are needed to neutralize these acids and precipitate out other heavy metal salts from the scrubber water before it can go overboard.

 

There is no requirement to burn diesel in the Med, though they are discussing creating an ECA there.  Currently, ships in EU ports must burn diesel fuel, but once outside they can switch back.

 

Not sure what you mean by the "IC process".  Do you mean "Compression Ignition"?  If so, then no, compression ignition engines are no less efficient in terms of complete combustion than spark ignition engines.  Effectiveness of combustion depends on the fuel/air ratio, the temperature and humidity of the air, the optimization of the fuel/air mixing (droplet size, surface tension, direction of air flow in the cylinder, and most importantly time.  Car engines (spark ignition) have catalytic converters to take out the byproducts of incomplete combustion caused by the small amount of time that the fuel is in the cylinder.

[lamchops]

https://www.cnn.com/2019/01/24/health/cruise-ship-air-quality-report/index.html

 

Fyi

 

just saw a report on our local news so I googled ship air quality and found this.

[chengkp75]

Far be it from me to dispute an assistant professor from Johns Hopkins, but the interesting fact is that given the 4 ships in the "study" and the itineraries involved, the ships would have been either burning low sulfur diesel fuel or using an exhaust scrubber designed to give the same emissions as the diesel fuel, for the majority of the cruises. Nothing is noted as to how many samples were collected on each ship, how many days samples were collected, the prevailing environmental conditions at the time of the samples (temperature, humidity, wind speed and direction) and several other facets that might change the "study's" findings.  Aside from this somewhat sketchy test procedure, the fact remains that the ships are operating within the legal limits set by the US EPA, and the IMO on the international level.

 

And I agree with the CLIA spokesperson when they point out that only the cruise industry is being targeted, when the cruise industry only accounts for about 5% of the world's shipping, which uses residual fuel almost universally.

 

Are the new emissions limits a good thing?  Yes.  Will it help the environment?  Yes.   I deal with these problems every working day of my life.  But what these "green" organisations are really interested in is the "green" of money, by targeting a high profile target, and one that won't raise the price of their BMW or Iphone due to increased shipping costs.  No mention is made of the IMO's resolution to limit sulfur in fuel to 0.5% (down from 3.5%) in 2020, which will automatically require all ships to have scrubbers or burn diesel fuel, as reducing sulfur in residual fuel to that level will pretty much price it out of use.  The next question is, what is to be done with the residual fuel once ships can no longer burn it, since it is not a product the refineries produce out of choice, it is merely what is left over after the refinery takes out all it can for refined products like jet fuel, gasoline, diesel, and lube oils.

[SRF]

19 hours ago, chengkp75 said:

Yes, particulate is reduced using lighter fuels, diesel and LNG, but not completely removed, but use of residual fuel does not produce "unhealthy" levels of particulates, despite efforts by environmental groups to portray this as the case.  Most of those articles have a data set of one ship, and one day, and don't mention the prevailing environmental conditions (wind, humidity, etc) at the time they took their readings.

 

As I mentioned in the other thread, for news purposes they typically compare the levels to air pollution limits.

 

Air pollution levers are based on a 24 hour per day, 365 day per year, 70 wear exposure.

 

Very few people spend 24 hours per day on their cruise, aft of the stacks.   Or VERY few spend 365 days per year (even crew does not).  And an EXTREMELY low number (as in ZERO), do so for 70 years.

 

And US EPA limits are typically based on a 1 in 1 Million persons exposed, increase in death or disease.  So if 1 million people, spend 24 hours a day, 365 days per year for 70 years, one extra person would die.

[ccsclean21]

Why don't cruise ships run on Nuclear power fuel, clean burning and ships can run for 20 years without refueling.  fossil fuels are running out and are expensive, so we need to look at other alternatives.   War ships and submarines run on Nuclear power with no problems.

everyone is complaining about rising fuel costs on the cruise lines and how bad the bunker fuels pollute and how you can get cancer from the smoke from the bunker fuel.

Maybe it is time we rethink about other alternatives that are less polluting and more efficient to run. 

Just an idea.  

[mom says]

Great idea. Because running a nuclear reactor is so risk free, and there would be no security risks at all.

[ccsclean21]

Glad you like the idea.  every time there is a nuclear accident it is pretty much always at a power stations and where do they put these power stations, they build them on fault lines.

Navies around the world have been using nuclear power for decades with great success unlike the power stations. 

[chengkp75]

35 minutes ago, ccsclean21 said:

Glad you like the idea.  every time there is a nuclear accident it is pretty much always at a power stations and where do they put these power stations, they build them on fault lines.

Navies around the world have been using nuclear power for decades with great success unlike the power stations. 

And those Navies running nuclear ships don't have to show a profit, so they can build in as many safeguards as possible.  And the number of crew that sail on these ships, even over the life of the ship, is very small compared to the number of passengers who sail on a cruise ship over it's life span.  And I can visualize that any passenger who ever sailed on a nuclear powered cruise ship that developed any cancer, at any time in their life afterwards, would immediately sue the cruise line.  Whether their cases have any merit or not, it would cost the cruise lines to defend those thousands (hundreds of thousands, millions?) of cases.

 

Why are there no nuclear powered cargo ships, since cruise ships only account for 5% or less of world shipping, wouldn't it be far more beneficial to repower cargo ships than the cruise ships?   Because building these ships is far more costly than building a fossil fueled ship, insurance rates would explode, and many ports do not allow nuclear powered ships into port.

 

I found a list of 29 nuclear power plant incidents, dating back to 1957, and none of them were caused by the fact that they were built on geographic fault lines.

[ccsclean21]

Thank you for your reply. Nuclear power engines on ships are very small where a diesel engine is massive. you will find that there is a couple of commercial ships that are nuclear powered and they have no issues, one is a Russian ice breaker and because it is nuclear it has power in reserve for the big tasks.

Sure you will get those people who sue because they have a right to sue but there can be protections put in place to restrict people from suing for instance when you enter a public car park you abide by their terms and conditions and if you don't like them then go park somewhere else, called limited liability i think it's called so the same with traveling on these ships you abide by the terms or don't sail on that ship. Admittedly I don't know much about nuclear power but what I do know is the good old fossil fuel is slowly running out and it is getting more expensive to get and in a few years or so the only ones who can afford the cruise fare will be the very rich. So we all need to think of better, safer and more cleaner ways to get around and get our products in from overseas. If you use wind well then you need to depend on the winds, then there is solar great on sunny days but you are screwed in a storm with no power because there is no sun and maybe we could use lithium battery power on the ships and it has it's own problems as well, so what do we use. I know give everyone an oar when they board and they can row, no need for a fitness center onboard and by the end of the cruise everyone will lose weight and will be fit.  but to be serious it is becoming harder for ships that use the old bunker fuel to get into some ports because of the sulfur in their fuels and how their engines burn the fuel.

[chengkp75]

I'm not sure where you get the idea that a nuclear propulsion system is small in comparison to a diesel one, but that is not correct. The nuclear plant requires the reactor and the primary circulation system, then the boilers, then the steam turbines, and the condenser and it's systems.

 

The only active nuclear merchant ships, and the only ones that operated in the past were Russian for a reason, Russia's lax regulatory atmosphere, and their disregard for safety or environmental conditions.

 

As for ships that burn bunker fuel getting into ports, the ECA's that require low sulfur fuel have been around for a while, and ships have complied using scrubbers or diesel fuel, and the existing ECA'S pretty much cover those countries that would care.

 

And if you think that building a nuclear cruise ship will keep fares low, I've got a bridge in Brooklyn to sell you.

[Donald]

Check out the history of America's first, only, and last nuclear passenger / cargo ship.

The NS Savannah.

It cost more than twice as much to build as a conventional ship, but carried only a fraction of the passengers and cargo of a conventional ship.

It required a high number of very expensive Nuclear Engineers to run it.

Design problems forced them to dump large quantities of radioactive water into the oceans.

Fueling it was prohibitively expensive - and could only be done in a very few locations.

Offloading spent fuel was nearly impossible.

It failed in nearly every possible way for 7 years until it was de-commissioned.

US Taxpayers took quite a bath on that one.

Edited August 31, 2019 by Donald

[ccsclean21]

yeah and when was that ship built 1959 I think we have advanced since then, you look at the ships back in 1959 they pretty much were coal burners. Nuclear power has come a long way since then so has the marine diesel engines, the ships that do have the nuclear power plants today the power plant is smaller and no need for ugly smoke stacks so there is more room even in the engine room and no need for bunker fuel tanks and again more space.  The ship can run on low enriched uranium not the highly enriched stuff on warships and subs plus nuclear powered ships can cruise at a lot higher speed and do it all day long.

I have news for you lot they are testing nuclear power on commercial ships like cargo carriers now so it's in the pipeline. You can't claim something that was build 60 years ago and pretend we have not advanced any further.  We are running out of the good oil so we need to find a way to advance to the next level in life or we just become ignorant and turn our backs on advancement, sure there needs a lot more work and research to be done on nuclear power but the world is full of uranium.  We have gained a lot of new technology from the military in the past that the military has tested and used and successful then unclassified it and we are using a lot of that technology today look at the internet for one.  If you can come up with a better way to run all the machinery then I am all ears.    

[mom says]

Look, if you think this is such a simple, sure fire idea, then feel free to write to the CEOs of all the major cruise lines about it. See how far it goes. We'll  all be waiting with baited breath.

[ccsclean21]

I don't need too because if there is a better fuel that's safe and cost effective then I think cruise lines will embrace it.

[chengkp75]

7 hours ago, ccsclean21 said:

I don't need too because if there is a better fuel that's safe and cost effective then I think cruise lines will embrace it.

Coal burning in 1959? Coal went out as primary ship's fuel in the '20's.

 

Please provide a link to someone other than the Russians who are "testing" nuclear cargo ships.

 

Have you ever been in the engine room of a steam ship (as a nuclear ship is) or a motor ship? Still would like to see the data that backs up the claim that the plant is smaller.

[DirtyDawg]

12 minutes ago, chengkp75 said:

Coal burning in 1959? Coal went out as primary ship's fuel in the '20's.

 

Please provide a link to someone other than the Russians who are "testing" nuclear cargo ships.

 

Have you ever been in the engine room of a steam ship (as a nuclear ship is) or a motor ship? Still would like to see the data that backs up the claim that the plant is smaller.

 

chengkp, I think someone down under has been smoking nuclear powered wacky tabacky. 😁