@Jake Chen It isn't the fact that engines produce CO2 but the fact it can be re-purposed instead of being released to the environment :) Makes sense but sometimes the 'simple' option isn't the first one we think of, as in my case.
I find it incredible that I don't have an interest in maritime study or whatever, and I can still enjoy these videos. You got me into learning about ships and how they worked, and sparked an interest in them. Keep up the awesome work!
Five minutes ago, I hadn’t ever considered the issue other than the analogous one of fuel tankers on the highways and roads where I believe at least in the US, safety has been improved over time through requirements of triple walled tanks and I’m sure inspection, valve and service life requirements. But, getting back to ships, your video perfectly laid out the problem and the solution (including both the scientific and economic aspects thereof). Well done!
I am an actual seafarer in tankers and this video helped me to better understand how the system works even simplified.. Wish it had other elements like PV V/V or PV Breaker.. This channel is gold! Also the sewage treatment helped me understand better..
It's not the quality, it's the topic. Not many people enjoy this kind of content, so you get low view count. Not many people watch because of food quality. Some (inducing me) do however watch not because of an interest in the subject but, conversely, the good quality makes me interested
Nitrogen is actually used in liquefied gas carriers containing things such as LNG, or LPG. The nitrogen is generated by on board generators (separating from the outside air) but it’s only used for maintenance and during cargo operations, normally the tanks are slightly pressurised so no air can come in anyway. CO2 and water will freeze under the operating conditions of these carriers.
I once had that experience on a picnic, when friend performed a "magic trick" for me: he filled the generator tank to the top with the canister, light a match, took a swing with his hat over the tank (to draw vapors away) and threw the match right into the filler. I was blown away with the physics on that matter.
@@afoxwithahat7846 The burn you'd get from touching liquid oxygen would be a very severe form of frostbite due to the extreme cold. Now if your clothing got saturated with liquid oxygen and encountered a spark that could cause a flash fire.
I'm retired from the USCG and was a Marine Inspector for about 20 years. I was inspecting a sport fishing boat in San Pedro once and noticed some planking on the bow was a different color than the wood it was adjacent to. I asked the owner about it. He laughed and said it was from the Sansinena II explosion. When the ship blew up a valve flew through the air about a mile and landed smack on the bow of this guy's boat. It went right through the boat which then immediately sank. That must have been a heck of an explosion.
I work in the petroleum industry and here the have a other alternative. make sure the tank is completely full with the product it self. then there cant get any oxygen in to it what you are talking about is here only used if a tank has to be made empty. then they do add nitrogen.
But the tank has to be emptied some stage , an oil tank that's permanently full ,and never emptied is worse than having no oil ,because you have to maintain the tank ,and theres a risk of leaking or fire ...
@@eastcorkcheeses6448 they do empty the tanks for maintenance. that's with in a planning. but all the other time it is best to keep it full and on pressure. on land it's easy you can raise or lower the top of the tank that way it is always full with in the space used.
Sorry to interfere. You can’t (are not allowed) to fill a shipstank upto 100%. 98% is the max. A floating roof system is very impractical. During the transfer the liquid is agitated and due to this biggest risk of static discharge is during the transfer and thats why you need to be fully inerted constantly at an oil tanker. During maintenance periods the tanks will be cleaned and gasfreed so safe acces is possible.
It might be worth pointing out that the inert gas, being a product of combustion is still mostly Nitrogen which is pretty much unchanged apart from small quantities of oxides produced. The combustion process of the Hydrocarbon fuel turns most of the oxygen into Carbon Dioxide and water vapour. During the scrubbing process, some of the Carbon Dioxide dissolves in the scrubbing tower so the percentage of Nitrogen in the inert gas becomes even higher- around 83-84%.with about 16%. There is always some residual oxygen- around 3%. I have not come across any installations using the main engine as a source of inert gas, these generally being shut down in port, but the gas being derived either from the flue gas of a boiler or a separate oil-fired inert gas generator.
Thanks for the explanation, i was confused after watching this video whether Nitrogen is the most part of inert gas or Co2..i had a doubt so if we are not using a scrubber tower how much percentage of Nitrogen will be there in the exhaust of boiler? Thanks
In the late 70s and early 80s two sister ships the Berge Istra and the Berge Vanga both dissapeared within a few years. As far as I remember they carried iron ore AND crude oil on different occasions (a practice not in use anymore) and somehow residue from the oil caused gas to build up whereas at some point the iron content in the ore may have caused sparks. None of the ships have ever been found (they dissapeared on the high oceans at places thousands of feet deep, in an era long before GPS navigation), but it was assumed they exploded and sank with no survivors.
As a welder and machinist we use these principles often when repairing tanks for various fuels, fluids or repurposing tanks (usually propane tanks) on a regular bases. Diesel and Hydraulic tanks are the least dangerous as they are closer on the scale to oil so flammable but not necessarily explosive. A flexible metal hose from the exhaust of a welding rig [truck] works more than well enough to be safe on those. And frankly convenient as you can see it come out the top most if the time as an indication it's full. Other fuels considered explosive we drain all of it which makes it more dangerous but pump in generous amounts of Argon because as a gas it's "heavy" so fills like something on the order of invisible water.. No oxygen sources....no fire....no explosion. Still a dangerous way to make a living but somebody has to do it. 🤷♂️ Excellent video explaintion for the general public so I hit the 👍 for you.
Very good, the title is very descriptive, as soon as I saw the title, I knew how it worked. But your narration and visuals are absolutely stunning! Keep it up!
You'll never fail to amaze me by the quality of your videos. Content and delivery. Very pleasant to watch. Thank you! You definitely deserve a ten fold increase in subscribers
Ex seafarer here. Most oil tankers I know use exhaust gas from the boiler instead of the exhaust from the diesel engine. The diesel engine can not produce enough inert gas at a rate needed during cargo discharging operation. Also, it would be difficult to bring down the residual O2 content of the exhaust from a diesel engine to a level that is considered safe (
As I watched Mythbusters the TV series, there's the thing called the Fire Triangle, and when sometimes they don't ignite, the Mythbusters need to adjust the gas ratio called Stoichiometry, like you said, between too lean & too rich.
As an engineer on board of ships, everything said is correct, but we are not using exhaust from Main Engine, or Auxiliary engines (generators), there are 2 options. One of them being Fired Steam boilers (using of their exhaust gases) and IGG (inert gas generator)
This channel is an one of the best sources that we seafarer uses most and also they make the topics easy to understand and fun.I am really grateful for this.
The Inert Gas Systems on tankships were originally designed and installed to prevent explosions during a process called Crude Oil Washing. Crude Oil is typically heated for loading aboard a tankship. After a lengthy voyage, the crude oil cools and this leaves a thick film on "walls" and "bottoms" of the cargo tank after discharging at the terminal. Owners and charterers realized this was lost profit (consider the vast surface area of these cargo tanks). Machinery was developed and a practice began to heat some of the cargo and "wash down" the tank surfaces with heated crude to remove the film of oil. The machinery was similar to a giant lawn sprinkler that sprayed in a spherical pattern. In the early days, crew dropped the "sprinklers" on long hoses, but eventually fixed systems were installed. So, how does this relate to Inert Gas Systems? Hot, sprayed oil in an almost empty oil tank with a rich oxygen atmosphere combined with a static electrical charge from the movement of the oil started causing explosions. Several vessels suffered casualties before the mystery was solved when the electrical charge was observed in shore side cargo tank mock - up (or so the story goes). Owners and operators not wanting to lose the profit from the washing operations looked the engineers to solve and the Inert Gas System was created. A video on the process of Crude Oil Washing could be informative and entertaining. Also, most diesel powered tankers will shut down their Main Engine in port. Very often a small Inert Gas Generator is installed (think a small boiler) and it's flue gas is scrubbed and pumped to the cargo tanks.
This guy is far too humble. He describes himself as a sailor, doesn't load up the video with ads, doesn't tell me to subscribe, like and ring the stupid bell. You sir are one of the last real humans left. The rest of us are either in pointless political hatred of people almost exactly like them , list videos with Cam girls or simon Whistler or fanatically on one side of another type of debate. You Sir are one of the few human beings left on RUclips
Since you asked, 1991, I was camping at Ilhabela, Brazil, when a tanker (Alina P) exploded right in front of us. All the sky turned orange, and the thunder seemed endless. Quite the fireworks for the end of the year. A spark from the anchor chain started it. Only one casualty.
Great video, though you forget what caused the explosion in the 1970's Los Angeles explosion, in the first place, was the infamous 'Disco Inferno.' Thank goodness disco is dead, saving many lives in the process.
naval engineer here. This video is generally accurate but a few notes: the CO2 usd to turn the atmoshere inside the tanks into non flammable actually comes from the boilers not the actual main engine.We engineers have to constantly kee an eye on the ratio of fuel-air to maintain a healthy level of oxygen well bellow 8% which is the safety limit(usually kept bellow 5%).The exhaust gas from the engine cant be used because that way the only way to produce inert gas would be at the times the ship is actually moving which is not the case. The steam produced by the boilers feeds into the cargo pumps abd their exhaust gas to neutralize the atmosphere inside the tanks. Great video however and great channel
I can look at all of these videos with a new perspective now as I'm working in the harbour of a Finnish oil refinery and I'm dealing with these ships every day at work✌🏼
Kind of shocked for the exploding tanker example you didn't go with the Mont-Blanc, which exploded with a force of 2.9 kilotons due to fires after crashing into another ship.
It is a little simplified in this presentation. If you were carrying crude oil you would use exhaust from the engine or the boilers however with refined products you would have a designated boiler that burns low sulfur gas oil or diesel. The exhaust from this boiler goes through a scrubber where sooth and impurities are washed out. Then the dew point of the exhaust is lowered either by a cooler or a filter filled with alumina before it is sent to the tank. When you mix inert and gas it is important to avoid “the sack” as we call it. The sack is the area on a diagram where the mixture is explosive. The area of the sack will depend on what kind of hydrocarbons you are carrying. If your cargo is a gas you have to go further. You will first inert the tank and then you will purge the inert with the gas you will be loading. You will need to get rid of as much as possible of the inert if you are going to reliquidfy the cargo. For chemical gasses like ethylene and butadiene you would use nitrogen as inert, while for propane and butane ordinary inert is ok. Since gasses are kept below the freezing point for water it is important to have a low dew point on the inert. For chemical gasses it is also to remove all oxygen to avoid contamination of the cargo.🤠
Note that the engine exhaust will also have a fair amount of nitrogen in it, if you don't specifically remove it, since engines are fed with ordinary air, not pure oxygen. It would make sense for every engine on the ship (not just the main engine) has an exhaust tap to feed into the inert gas system, so that the system can keep working even when the ship is moored. If you needed nitrogen without exhaust contaminants, you could (at least in principle) use a giant version of one of those machines that concentrates oxygen for medical use (by nature, it must also produce an output stream of gas depleted in oxygen). Would cost more to install than liquid nitrogen storage, but would probably be cheaper in the long run (even though it would require some power), due to the large amount of energy needed to liquify nitrogen (even if done on shore); also, you wouldn't need to worry about the liquid nitrogen running out if the ship was delayed, as long as the ship's fuel didn't run out. Of course, the exception would be those liquid cargoes that can't tolerate even the little bit of oxygen that would be left in the oxygen-depleted output of such a machine (for instance, something that would polymerize with oxygen, or form peroxides or otherwise go rancid -- unsaturated hydrocarbons and vegetable oils come to mind -- these also wouldn't be good to pass even cleaned engine exhaust through either).
Thats the reason chemical tankers use only N2 as inerting gas. Depending on the cargo the O2% lays between 7 and 0.00001% and typicaly the very high purity delivered via the shore before loading or via cilinders for padding during transit. Liquid n2 storage takes more space and equipment than a n2 generator this is the reason you only see n2 generators on board. Normaly via a kind of osmoses system.
"so that the system can keep working even when the ship is moored." When they are moored they are either loading or unloading and the tanks that they are pumping their fuel into are also filled with the same gas so all they do is pump fuel out and get gas back from that other tank. "Would cost more to install than liquid nitrogen storage, " They don't need liquid nitrogen, just nitrogen. There is absolutely no need to cool the gas to -200 celcius and liquify it. "If you needed nitrogen without exhaust contaminants, you could..." This video literally explains how they do that. You don't have to suggest a solution, they altready have it. " as long as the ship's fuel didn't run out. " The gas is sealed in the tank, there is no need to keep pumping in more gas. Once the pressure is correct, the gasflow can stop. The gas is *only* there to keep the oxygen levels below the flammable limit. A 320,000m3 tank does not need 320,000m3 of liquid nitrogen to keep it's tanks safe, it just has to keep the empty parts of it's tanks below X% oxygen and given that the tanks are never empty all at the same time, the amount of gas they need is actually not that huge.
Cars don't explode, ever, unless they are props in action movies. Even gas powered cars vent their fuel rather than letting the tank rupture. Their tires often burst though, or the small explosive charges in their airbags may cook off. Also the smoke is highly toxic (like all dense smoke). Which is why modern day, well trained fire fighters approach them at an angle, and never without heat protective clothing and breathing gear.
Fun fact, the vapor pressure from JP-4 jet fuel (as used on military aircraft) was just right to form an explosive mixture. It has, naturally, been replaced.
The Halifax explosion. December 6th 1917 is the worst ship explosion I have ever heard of. There was 1782 confirmed casualties. The ss mont-blanc. Collided with another ship while in port with. The resulting explosion was the equivalent of 2.9 kilotons of TNT.
The CO2 generator which is used to inert the tanks should be the Boilers and not the Main engine itself. 'cos: 1. Main engines emit way too much oxygen in their exhaust. 2.Many times when you need the inert gas (in port, while discharging cargo) your main engine isn't running. Correct me if I'm wrong. Thoroughly enjoyed your video thank you.
I kind of had the opposite question until I realized that the tanks won't always be 100% full. If they were, then a true explosion would be very unlikely because there just wouldn't be enough oxygen able to get in contact. Not that a plain fire can't be plenty nasty, but it's not going to be "break windows miles away" nasty. But when you showed the half full tank and talked about the vapors, I realized "oh shit, that's a fuel-air explosive".
In the 70’s three VLCC’s blew up off of the coast of Southern Africa. Shell UK’s Mactra, Shell BV’s Marpesea and a chartered in Norwegian vessel the Kong Hakon. This was in the age when the oil industry was trying to decide if they would go to ‘too rich’, ‘too lean’ or inert atmosphere for crude oil washing (COW) the three ships went off within a few days of each other so ‘something had to be done’ and as you describe inert was chosen. Even as the poor ship owners and operated cried tears of misery over the cost. It is seldom difficult to notice the difference between a ship owners forced to pay for safety and a ray of sun shine (:-)
This is interesting. At that time I was an engineer on VLCCs and naturally all officers were seriously concerned. The investigation to all 3 incidents concluded that an electrostacticly induced spark occurred in the tanks while cleaning with high pressure water guns. Inert gas equipment was installed on all company steam ships at next dry dock, much to our relief. After a number of years water cleaning was displaced by using crude oil instead while tank cleaning, creating a too rich atmosphere in the cargo tanks, therefore not explosive.
The Mactra didn't sink and limped into Durban for emergancy repairs, if you Google search "What happened to the STS Mactra" there are photos of the massive hole in her deck. She was eventually repaired and was finally scrapped in the early 80s.
In 2004 a ship exploded. it wasn't when they're hauling cargo it was when they're cleaning out the tanks if you want to learn more the ship's name is bow Mariner
Generally the exhaust from the boiler is used since the exhaust fumes from ME contains to much oxygen. But many oiltankers are not equipped with an Inert gas generator, it didn’t used to be a requirement. All electric equipment on deck in cargo area is Ex proof and strict regulations regarding allowed tools. So the risk of an explosion is still low because there is no source of ignition.
this video is great! Only nitpick would be that you should maybe think about using some more contrasting colours on something like the flammability graph.
Isnt the exhaust from onboard boilers the most common exhaust gas used for this purpose. You cant have the main engine running while the ship is in port since you cant disconnect the propeller feom the driveshaft/crankshaft. I just started my cadetship on a tanker ship and this is what i was taught. Btw we use a dedicated burner for the purpose.
Ok I've been watching a lot of sci shows just about every mainstream one there is but this is just as good if not a better channel with a very low following I couldn't imagine the videos that this creator could make with a higher volume of subscribers
Once upon a time long ago, We used to operate to rich or to lean. The San Demitro was quite famously hit by shells from a pocket battle ship causing fires. She was abandoned but some of the crew reborded put the fires out and sailed it to port. A full gas can will not explode it’s to rich. So ypu can torpedo or she’ll a loaded tanker and the tank won’t blow up. An empty tanker. If it’s to rich will not blow up ither. But when you unload it regular air with its regular oxygen content is sucked in. An empty tank full of a fuel air mixture can blow up quite spectacularly. So funny thing is an empty can of gas is much more dangerous than a full one. Ussualy even when the unloading a tanker there was enough hydrocarbon to keep it to rich. The really dangerous time was tank cleaning when you clean the tanks you get ride of the fuel. And it is possible for the tank to go from to rich into the danger zone. After several ships blew up during tank cleaning. IG systems were gradually introduced. Crude oil is one of the more volatile due to still having a lot of the light gassy stuff still as part of it. At first only crude oil tankers had IG systems, but a few refined product tankers blew up while tank cleaning, so it’s use became more widespread I worked on some of the last Non IG tankers. While loading, particularly topping of tanks, if there was not a lot of wind there was so much fumes I’d actually get high on it. Diesel or Gas oil is much less volatile. But still can be a problem as can ATK aviation turbine kerosene. Heavier oils aren’t much of a problem you can make roads out of them. The crap ships typically use is a slight step above road tar you heat it up enough it will burn. And is full of sulfer. So getting banned in lots of places. And is why IG systems are very prone to rust.
One of the reasons tankers will not explode is that the RON is low compared to refined petrol , thats why when a tanker goes on fire it burns and does not explode , unless it is one that is carrying refined fuel . I sailed on a few , gas and crude , the early ones never had the system to vent exhaust gasses from the main engine into the tanks and you always had the smell of crude oil in the air , there were just vent pipes to let it out of the tanks , a later one , the ''Sir Alexander Glen '' an OBO had the exhaust gas system and was a lot safer but still someything always to be causious of . The gas tanker , butane and propane had tanks on deck with Nitrogene for toping off when fully loaded or for flushing the tanks . That one also had a compartment on deck with two banks of compressors , run alternatly to keep the gas under pressure to keep it in a liquide form
You don't use the exhaust from the (main) engines. Actually the exhaust gasses contains too much oxygen about 15%. The CO2 is made in a dedicated machine called the Inert Gas Generator (IGG). the inert gas contains about 2-3% oxygen.
@Grigory S No they don't. Only specialized chemical tankers have might have other inert gasses. VLCCs have IGG too. They need to produce at the same capacity of discharge, which for a VLCC can be 10-15,000 cbm/hr
@Grigory S Posted edited. But I will secede to your point for a while... I will look into it further, next time I am on a VLCC. I don't normally have access to the engine room, so I might be biased from other experiences. I have seen IGG in use on a 250 m long LNG carrier for maintenance purposes , and that was quite big and used a lot of diesel.
If i remember this isn't really a new new tech either, in 1940s during WW2 American carriers would flood their avaitor fuel pipes with CO2 to try to minimize the damage of fires, of course this doesn't stop chain reaction of bombs going off but this was a critical feature that was added and helped keep a carrier fighting during the battle of midway when it should have been lost the first time around.
The last time, it started with a call from the support department. They wanted to know if I had a backdoor tool that could dump the memory from a particular industrial controller without turning it on, because this particular controller had been extracted from Panam Serena, a chemical tanker that had exploded in Porto Torres. Sadly it turned out that our controller had lost power 10 minutes before the bang, so we didn't have sensor data for them, but that also told them something.
everyone from istanbul remebers the 1979 independenta explosion. it was in the middle of the bosphorus, shattered every glass in the town. massive accident.
The LA explosion was ammonium nitrate, which can explode without oxygen. It simply decomposes in an exothermic chain reaction into NO2 and H2O when ignited. This is why it is commonly used for explosives. Whether it had an inert gas or not would have been irrelevant.
Another thing the heavy tankers most people think of leaving the middle East are full of unrefined crude which put off little vapor to begin with and is not explosive
You are very badly mistaken; crude oil is volatile even the heaviest such as the Venezuelan crudes for around the Maracibo Lake contains a small fraction of light elements.
Learned something new this morning. I never thought of using the engine exhaust to get the CO2. I had just assumed they were using nitrogen.
@joecugo wtf dude
@joecugo lol
@@tolga1cool what?
@Jake Chen It isn't the fact that engines produce CO2 but the fact it can be re-purposed instead of being released to the environment :) Makes sense but sometimes the 'simple' option isn't the first one we think of, as in my case.
@@berndknauer5211 What exatly has the free oxygen to to with your nitrogen production? :-D
Human ingenuity never ceases to amaze me
That why we conqure the world
Too bad we are still killing each other instead of working together to maybe...let's say explore the space as a human race.
Tell me Hoo-man, what is this thing you call 'love?'
Never underestimate the persistence of stupidity.
@@siechamontillado underrated comment
I find it incredible that I don't have an interest in maritime study or whatever, and I can still enjoy these videos. You got me into learning about ships and how they worked, and sparked an interest in them. Keep up the awesome work!
Thank Avionic7779x. It's great to hear you are enjoying the videos
Haha, you didn't have an interest in ships, but now you do!
The RUclips algorithm works in mysterious ways
@@Skwerll neural networks, three of them actually
@@Skwerll I lookloke the grindy person which wants every body to use the right terminology.
Five minutes ago, I hadn’t ever considered the issue other than the analogous one of fuel tankers on the highways and roads where I believe at least in the US, safety has been improved over time through requirements of triple walled tanks and I’m sure inspection, valve and service life requirements. But, getting back to ships, your video perfectly laid out the problem and the solution (including both the scientific and economic aspects thereof). Well done!
Thanks Paul.
I am an actual seafarer in tankers and this video helped me to better understand how the system works even simplified.. Wish it had other elements like PV V/V or PV Breaker.. This channel is gold! Also the sewage treatment helped me understand better..
It vexes me to see such a talented and wonderful creator like yourself have so little subscribers. I hope you make it big.
Thanks Ritvik. I just do it for enjoyment anyway, but it's always nice to hear the content is enjoyed.
It's not the quality, it's the topic. Not many people enjoy this kind of content, so you get low view count. Not many people watch because of food quality. Some (inducing me) do however watch not because of an interest in the subject but, conversely, the good quality makes me interested
Didn’t check the # of his subscribers, but yeah, I love his content. Super talented! So well explained and animated. Cheers
Nitrogen is actually used in liquefied gas carriers containing things such as LNG, or LPG. The nitrogen is generated by on board generators (separating from the outside air) but it’s only used for maintenance and during cargo operations, normally the tanks are slightly pressurised so no air can come in anyway.
CO2 and water will freeze under the operating conditions of these carriers.
He was talking specifically about the fuel tanks, not the cargo like lng
I'm currently studying to become a deck officer so these videos are golden.
somehow your channel is such a comfy place despite the fact that the sea terrifies me like hell
I once had that experience on a picnic, when friend performed a "magic trick" for me: he filled the generator tank to the top with the canister, light a match, took a swing with his hat over the tank (to draw vapors away) and threw the match right into the filler.
I was blown away with the physics on that matter.
Actually pure oxygen is more dangerous than most fuels. Pure oxygen can set on fire things that are normally are not flammable.
@@dtibor5903 in that case the thing set in fire becomes the fuel
@@LiborTinka for example, your skin.
Usually you'd get burned instead of burning, but if you touch liquid Oxygen you're screwed.
@@afoxwithahat7846 The burn you'd get from touching liquid oxygen would be a very severe form of frostbite due to the extreme cold. Now if your clothing got saturated with liquid oxygen and encountered a spark that could cause a flash fire.
2:05 - Spain are responsible for all fuel fires apparently.
I knew it!!
those bastards, WE GOT TA DO SOMETHING ABOUT EM
Because no one ever expects them, they get away with it.
So that's what happened to the USS Maine
@@peterson7082 no one expect the Spanish inquisition hueheueheheh.
I'm retired from the USCG and was a Marine Inspector for about 20 years. I was inspecting a sport fishing boat in San Pedro once and noticed some planking on the bow was a different color than the wood it was adjacent to. I asked the owner about it. He laughed and said it was from the Sansinena II explosion. When the ship blew up a valve flew through the air about a mile and landed smack on the bow of this guy's boat. It went right through the boat which then immediately sank. That must have been a heck of an explosion.
I work in the petroleum industry and here the have a other alternative. make sure the tank is completely full with the product it self. then there cant get any oxygen in to it
what you are talking about is here only used if a tank has to be made empty. then they do add nitrogen.
Similar on ships. When the tank is full it is fine. Loading and discharging are the highest risk times
@@CasualNavigation that i am aware of. here the biggest risk is the friction you get during the discharging.
But the tank has to be emptied some stage , an oil tank that's permanently full ,and never emptied is worse than having no oil ,because you have to maintain the tank ,and theres a risk of leaking or fire ...
@@eastcorkcheeses6448 they do empty the tanks for maintenance. that's with in a planning. but all the other time it is best to keep it full and on pressure. on land it's easy you can raise or lower the top of the tank that way it is always full with in the space used.
Sorry to interfere. You can’t (are not allowed) to fill a shipstank upto 100%. 98% is the max. A floating roof system is very impractical. During the transfer the liquid is agitated and due to this biggest risk of static discharge is during the transfer and thats why you need to be fully inerted constantly at an oil tanker.
During maintenance periods the tanks will be cleaned and gasfreed so safe acces is possible.
Very interesting video, I hope it EXPLODES with views and likes!
Thanks Tom. I enjoy making them regardless, but it's nice knowing people enjoy watching too
It might be worth pointing out that the inert gas, being a product of combustion is still mostly Nitrogen which is pretty much unchanged apart from small quantities of oxides produced. The combustion process of the Hydrocarbon fuel turns most of the oxygen into Carbon Dioxide and water vapour.
During the scrubbing process, some of the Carbon Dioxide dissolves in the scrubbing tower so the percentage of Nitrogen in the inert gas becomes even higher- around 83-84%.with about 16%.
There is always some residual oxygen- around 3%.
I have not come across any installations using the main engine as a source of inert gas, these generally being shut down in port, but the gas being derived either from the flue gas of a boiler or a separate oil-fired inert gas generator.
Thanks for the explanation, i was confused after watching this video whether Nitrogen is the most part of inert gas or Co2..i had a doubt so if we are not using a scrubber tower how much percentage of Nitrogen will be there in the exhaust of boiler? Thanks
In the late 70s and early 80s two sister ships the Berge Istra and the Berge Vanga both dissapeared within a few years. As far as I remember they carried iron ore AND crude oil on different occasions (a practice not in use anymore) and somehow residue from the oil caused gas to build up whereas at some point the iron content in the ore may have caused sparks.
None of the ships have ever been found (they dissapeared on the high oceans at places thousands of feet deep, in an era long before GPS navigation), but it was assumed they exploded and sank with no survivors.
As a welder and machinist we use these principles often when repairing tanks for various fuels, fluids or repurposing tanks (usually propane tanks) on a regular bases.
Diesel and Hydraulic tanks are the least dangerous as they are closer on the scale to oil so flammable but not necessarily explosive.
A flexible metal hose from the exhaust of a welding rig [truck] works more than well enough to be safe on those. And frankly convenient as you can see it come out the top most if the time as an indication it's full.
Other fuels considered explosive we drain all of it which makes it more dangerous but pump in generous amounts of Argon because as a gas it's "heavy" so fills like something on the order of invisible water..
No oxygen sources....no fire....no explosion.
Still a dangerous way to make a living but somebody has to do it. 🤷♂️
Excellent video explaintion for the general public so I hit the 👍 for you.
Actual "explosives" may contain enough oxygen to combust without needing contact with an external source of oxygen - dynamite, gunpowder, etc
Very good, the title is very descriptive, as soon as I saw the title, I knew how it worked. But your narration and visuals are absolutely stunning! Keep it up!
Thanks Great Canadian Moose. Glad you enjoyed it
Cars actually don't explode all that violently, the damage done by the explosion is surprisingly minor. The fire does most of the damage.
You'll never fail to amaze me by the quality of your videos. Content and delivery. Very pleasant to watch. Thank you! You definitely deserve a ten fold increase in subscribers
Thanks Guillaume. Glad you are enjoying the content.
3:49 Nuclear reactors release minimal to no CO2. The clouds they produce is from water used for cooling/turbines that has been treated.
I think those are coal power plants.
Those are cooling towers, they can be used in any system/powerplant that produces heat.
Casual Navigation animation his ship explosions.
Ship: **Literally Dissapears**
Youre telling me i have to wait 2 WEEKS for another video?!?
Nothing like the thrill of learning something new on a Sunday morning.
The wendover productions of the seven seas
What about a spin-off channel; half as deep?
Ex seafarer here. Most oil tankers I know use exhaust gas from the boiler instead of the exhaust from the diesel engine. The diesel engine can not produce enough inert gas at a rate needed during cargo discharging operation. Also, it would be difficult to bring down the residual O2 content of the exhaust from a diesel engine to a level that is considered safe (
Huh, random recommendation, and I was pleased.
As I watched Mythbusters the TV series, there's the thing called the Fire Triangle, and when sometimes they don't ignite, the Mythbusters need to adjust the gas ratio called Stoichiometry, like you said, between too lean & too rich.
good to have you back from your break, missed these vids
Thanks Odeh. Glad you are enjoying them
All maritime technology explained in ways everyone can understand. Excellent channel.
As an engineer on board of ships, everything said is correct, but we are not using exhaust from Main Engine, or Auxiliary engines (generators), there are 2 options. One of them being Fired Steam boilers (using of their exhaust gases) and IGG (inert gas generator)
I've learned so much about ships from you channel, apreciate you man!
This channel is an one of the best sources that we seafarer uses most and also they make the topics easy to understand and fun.I am really grateful for this.
The Inert Gas Systems on tankships were originally designed and installed to prevent explosions during a process called Crude Oil Washing. Crude Oil is typically heated for loading aboard a tankship. After a lengthy voyage, the crude oil cools and this leaves a thick film on "walls" and "bottoms" of the cargo tank after discharging at the terminal. Owners and charterers realized this was lost profit (consider the vast surface area of these cargo tanks). Machinery was developed and a practice began to heat some of the cargo and "wash down" the tank surfaces with heated crude to remove the film of oil. The machinery was similar to a giant lawn sprinkler that sprayed in a spherical pattern. In the early days, crew dropped the "sprinklers" on long hoses, but eventually fixed systems were installed. So, how does this relate to Inert Gas Systems? Hot, sprayed oil in an almost empty oil tank with a rich oxygen atmosphere combined with a static electrical charge from the movement of the oil started causing explosions. Several vessels suffered casualties before the mystery was solved when the electrical charge was observed in shore side cargo tank mock - up (or so the story goes). Owners and operators not wanting to lose the profit from the washing operations looked the engineers to solve and the Inert Gas System was created. A video on the process of Crude Oil Washing could be informative and entertaining.
Also, most diesel powered tankers will shut down their Main Engine in port. Very often a small Inert Gas Generator is installed (think a small boiler) and it's flue gas is scrubbed and pumped to the cargo tanks.
Clear and concise explanation and in a video that's not too long. Good job! 👍
The narrators accent makes the content of these videos at least twice as interesting to watch.
This guy is far too humble. He describes himself as a sailor, doesn't load up the video with ads, doesn't tell me to subscribe, like and ring the stupid bell.
You sir are one of the last real humans left. The rest of us are either in pointless political hatred of people almost exactly like them , list videos with Cam girls or simon Whistler or fanatically on one side of another type of debate.
You Sir are one of the few human beings left on RUclips
Since you asked, 1991, I was camping at Ilhabela, Brazil, when a tanker (Alina P) exploded right in front of us. All the sky turned orange, and the thunder seemed endless. Quite the fireworks for the end of the year. A spark from the anchor chain started it. Only one casualty.
Great video, though you forget what caused the explosion in the 1970's Los Angeles explosion, in the first place, was the infamous 'Disco Inferno.' Thank goodness disco is dead, saving many lives in the process.
naval engineer here. This video is generally accurate but a few notes: the CO2 usd to turn the atmoshere inside the tanks into non flammable actually comes from the boilers not the actual main engine.We engineers have to constantly kee an eye on the ratio of fuel-air to maintain a healthy level of oxygen well bellow 8% which is the safety limit(usually kept bellow 5%).The exhaust gas from the engine cant be used because that way the only way to produce inert gas would be at the times the ship is actually moving which is not the case. The steam produced by the boilers feeds into the cargo pumps abd their exhaust gas to neutralize the atmosphere inside the tanks. Great video however and great channel
That was the weirdest way someone has ever introduced a mathematical graph to me
Why does he show a nuclear power plant when talking about CO 2 ?
I was wondering the same thing, why do people still think nuclear power had to do with CO2
At last a channel having content for my job, I am a Fourth Mate. Very good representation of IG, one thing though your Tanker misses the BRAVO flag.
Meanwhile Iran: Excuse me?
I can look at all of these videos with a new perspective now as I'm working in the harbour of a Finnish oil refinery and I'm dealing with these ships every day at work✌🏼
Wooo new CN video
Keep up the great work man
I love your videos, as a fellow mariner (used to) I can say that your knowledge is amazing, thank you for sharing with us!
I have never sailed in my live yet I watch your channel religiously lol
Using millions of small explosions to prevent a massive one. Incredible.
These videos are informative and great for relaxing before sleep.
I know nothing about ships, and was not particularly interested in them until coming across this channel. Facinating stuff! Liked and subbed
There was also the explosion of the oil tanker Betelgeuse at Whiddy Island in 1979. 50 people were killed.
2:00 No, we're left with the Spanish flag.
Some military aircraft have used a similar system in their fuel tanks to lessen explosive risks in combat.
Kind of shocked for the exploding tanker example you didn't go with the Mont-Blanc, which exploded with a force of 2.9 kilotons due to fires after crashing into another ship.
Mont blanc was a munitions' ship. Full of explosives, Another massive ship exposition was Grandcamp in Texas City, that was ammonium nitrate/
It is a little simplified in this presentation. If you were carrying crude oil you would use exhaust from the engine or the boilers however with refined products you would have a designated boiler that burns low sulfur gas oil or diesel. The exhaust from this boiler goes through a scrubber where sooth and impurities are washed out. Then the dew point of the exhaust is lowered either by a cooler or a filter filled with alumina before it is sent to the tank. When you mix inert and gas it is important to avoid “the sack” as we call it. The sack is the area on a diagram where the mixture is explosive. The area of the sack will depend on what kind of hydrocarbons you are carrying. If your cargo is a gas you have to go further. You will first inert the tank and then you will purge the inert with the gas you will be loading. You will need to get rid of as much as possible of the inert if you are going to reliquidfy the cargo. For chemical gasses like ethylene and butadiene you would use nitrogen as inert, while for propane and butane ordinary inert is ok. Since gasses are kept below the freezing point for water it is important to have a low dew point on the inert. For chemical gasses it is also to remove all oxygen to avoid contamination of the cargo.🤠
Note that the engine exhaust will also have a fair amount of nitrogen in it, if you don't specifically remove it, since engines are fed with ordinary air, not pure oxygen.
It would make sense for every engine on the ship (not just the main engine) has an exhaust tap to feed into the inert gas system, so that the system can keep working even when the ship is moored.
If you needed nitrogen without exhaust contaminants, you could (at least in principle) use a giant version of one of those machines that concentrates oxygen for medical use (by nature, it must also produce an output stream of gas depleted in oxygen). Would cost more to install than liquid nitrogen storage, but would probably be cheaper in the long run (even though it would require some power), due to the large amount of energy needed to liquify nitrogen (even if done on shore); also, you wouldn't need to worry about the liquid nitrogen running out if the ship was delayed, as long as the ship's fuel didn't run out. Of course, the exception would be those liquid cargoes that can't tolerate even the little bit of oxygen that would be left in the oxygen-depleted output of such a machine (for instance, something that would polymerize with oxygen, or form peroxides or otherwise go rancid -- unsaturated hydrocarbons and vegetable oils come to mind -- these also wouldn't be good to pass even cleaned engine exhaust through either).
Thats the reason chemical tankers use only N2 as inerting gas. Depending on the cargo the O2% lays between 7 and 0.00001% and typicaly the very high purity delivered via the shore before loading or via cilinders for padding during transit. Liquid n2 storage takes more space and equipment than a n2 generator this is the reason you only see n2 generators on board. Normaly via a kind of osmoses system.
"so that the system can keep working even when the ship is moored."
When they are moored they are either loading or unloading and the tanks that they are pumping their fuel into are also filled with the same gas so all they do is pump fuel out and get gas back from that other tank.
"Would cost more to install than liquid nitrogen storage, "
They don't need liquid nitrogen, just nitrogen. There is absolutely no need to cool the gas to -200 celcius and liquify it.
"If you needed nitrogen without exhaust contaminants, you could..."
This video literally explains how they do that. You don't have to suggest a solution, they altready have it.
" as long as the ship's fuel didn't run out. "
The gas is sealed in the tank, there is no need to keep pumping in more gas. Once the pressure is correct, the gasflow can stop.
The gas is *only* there to keep the oxygen levels below the flammable limit. A 320,000m3 tank does not need 320,000m3 of liquid nitrogen to keep it's tanks safe, it just has to keep the empty parts of it's tanks below X% oxygen and given that the tanks are never empty all at the same time, the amount of gas they need is actually not that huge.
I really really look forward for a video for the inert gas system, please make one!!
Cars don't explode, ever, unless they are props in action movies. Even gas powered cars vent their fuel rather than letting the tank rupture. Their tires often burst though, or the small explosive charges in their airbags may cook off. Also the smoke is highly toxic (like all dense smoke). Which is why modern day, well trained fire fighters approach them at an angle, and never without heat protective clothing and breathing gear.
Cars did explode in the past. The main reason being the fuel tank inside the passanger or cargo space. Safety standards evolved a lot in this regard.
0:39 lol anyone else notice the shockwave knock over the Hollywood sign and trees?
Fun fact, the vapor pressure from JP-4 jet fuel (as used on military aircraft) was just right to form an explosive mixture. It has, naturally, been replaced.
The Halifax explosion. December 6th 1917 is the worst ship explosion I have ever heard of. There was 1782 confirmed casualties. The ss mont-blanc. Collided with another ship while in port with. The resulting explosion was the equivalent of 2.9 kilotons of TNT.
The CO2 generator which is used to inert the tanks should be the Boilers and not the Main engine itself. 'cos:
1. Main engines emit way too much oxygen in their exhaust. 2.Many times when you need the inert gas (in port, while discharging cargo) your main engine isn't running.
Correct me if I'm wrong. Thoroughly enjoyed your video thank you.
We dont use main engine exhaust...it contains oxygen due to scavanging...we use boiler exhaust for inert gas system
This is very useful
I kind of had the opposite question until I realized that the tanks won't always be 100% full. If they were, then a true explosion would be very unlikely because there just wouldn't be enough oxygen able to get in contact. Not that a plain fire can't be plenty nasty, but it's not going to be "break windows miles away" nasty. But when you showed the half full tank and talked about the vapors, I realized "oh shit, that's a fuel-air explosive".
In the 70’s three VLCC’s blew up off of the coast of Southern Africa. Shell UK’s Mactra, Shell BV’s Marpesea and a chartered in Norwegian vessel the Kong Hakon. This was in the age when the oil industry was trying to decide if they would go to ‘too rich’, ‘too lean’ or inert atmosphere for crude oil washing (COW) the three ships went off within a few days of each other so ‘something had to be done’ and as you describe inert was chosen. Even as the poor ship owners and operated cried tears of misery over the cost. It is seldom difficult to notice the difference between a ship owners forced to pay for safety and a ray of sun shine (:-)
This is interesting. At that time I was an engineer on VLCCs and naturally all officers were seriously concerned. The investigation to all 3 incidents concluded that an electrostacticly induced spark occurred in the tanks while cleaning with high pressure water guns. Inert gas equipment was installed on all company steam ships at next dry dock, much to our relief. After a number of years water cleaning was displaced by using crude oil instead while tank cleaning, creating a too rich atmosphere in the cargo tanks, therefore not explosive.
The Mactra didn't sink and limped into Durban for emergancy repairs, if you Google search "What happened to the STS Mactra" there are photos of the massive hole in her deck. She was eventually repaired and was finally scrapped in the early 80s.
In 2004 a ship exploded. it wasn't when they're hauling cargo it was when they're cleaning out the tanks if you want to learn more the ship's name is bow Mariner
Generally the exhaust from the boiler is used since the exhaust fumes from ME contains to much oxygen. But many oiltankers are not equipped with an Inert gas generator, it didn’t used to be a requirement. All electric equipment on deck in cargo area is Ex proof and strict regulations regarding allowed tools. So the risk of an explosion is still low because there is no source of ignition.
this video is great!
Only nitpick would be that you should maybe think about using some more contrasting colours on something like the flammability graph.
Thanks Declan. I always welcome constructive criticism.
Isnt the exhaust from onboard boilers the most common exhaust gas used for this purpose. You cant have the main engine running while the ship is in port since you cant disconnect the propeller feom the driveshaft/crankshaft. I just started my cadetship on a tanker ship and this is what i was taught. Btw we use a dedicated burner for the purpose.
Ships no longer have boilers as they no longer use steam turbines.
@@samanli-tw3id they have auxiliary boilers and many tankers have steam turbine cargo pumps.
I like how the engine is a fancy V10.
Ok I've been watching a lot of sci shows just about every mainstream one there is but this is just as good if not a better channel with a very low following I couldn't imagine the videos that this creator could make with a higher volume of subscribers
Once upon a time long ago, We used to operate to rich or to lean.
The San Demitro was quite famously hit by shells from a pocket battle ship causing fires. She was abandoned but some of the crew reborded put the fires out and sailed it to port.
A full gas can will not explode it’s to rich. So ypu can torpedo or she’ll a loaded tanker and the tank won’t blow up.
An empty tanker. If it’s to rich will not blow up ither. But when you unload it regular air with its regular oxygen content is sucked in.
An empty tank full of a fuel air mixture can blow up quite spectacularly. So funny thing is an empty can of gas is much more dangerous than a full one.
Ussualy even when the unloading a tanker there was enough hydrocarbon to keep it to rich.
The really dangerous time was tank cleaning when you clean the tanks you get ride of the fuel. And it is possible for the tank to go from to rich into the danger zone.
After several ships blew up during tank cleaning. IG systems were gradually introduced.
Crude oil is one of the more volatile due to still having a lot of the light gassy stuff still as part of it.
At first only crude oil tankers had IG systems, but a few refined product tankers blew up while tank cleaning, so it’s use became more widespread
I worked on some of the last Non IG tankers.
While loading, particularly topping of tanks, if there was not a lot of wind there was so much fumes I’d actually get high on it.
Diesel or Gas oil is much less volatile. But still can be a problem as can ATK aviation turbine kerosene.
Heavier oils aren’t much of a problem you can make roads out of them. The crap ships typically use is a slight step above road tar you heat it up enough it will burn. And is full of sulfer. So getting banned in lots of places.
And is why IG systems are very prone to rust.
Love the explosion animations
One of the reasons tankers will not explode is that the RON is low compared to refined petrol , thats why when a tanker goes on fire it burns and does not explode , unless it is one that is carrying refined fuel . I sailed on a few , gas and crude , the early ones never had the system to vent exhaust gasses from the main engine into the tanks and you always had the smell of crude oil in the air , there were just vent pipes to let it out of the tanks , a later one , the ''Sir Alexander Glen '' an OBO had the exhaust gas system and was a lot safer but still someything always to be causious of . The gas tanker , butane and propane had tanks on deck with Nitrogene for toping off when fully loaded or for flushing the tanks . That one also had a compartment on deck with two banks of compressors , run alternatly to keep the gas under pressure to keep it in a liquide form
could you do some videos about marine diesel engines in upcoming weeks... would be really helpfull
You don't use the exhaust from the (main) engines. Actually the exhaust gasses contains too much oxygen about 15%.
The CO2 is made in a dedicated machine called the Inert Gas Generator (IGG). the inert gas contains about 2-3% oxygen.
@Grigory S No they don't. Only specialized chemical tankers have might have other inert gasses.
VLCCs have IGG too. They need to produce at the same capacity of discharge, which for a VLCC can be 10-15,000 cbm/hr
@Grigory S
Posted edited.
But I will secede to your point for a while... I will look into it further, next time I am on a VLCC.
I don't normally have access to the engine room, so I might be biased from other experiences.
I have seen IGG in use on a 250 m long LNG carrier for maintenance purposes , and that was quite big and used a lot of diesel.
If i remember this isn't really a new new tech either, in 1940s during WW2 American carriers would flood their avaitor fuel pipes with CO2 to try to minimize the damage of fires, of course this doesn't stop chain reaction of bombs going off but this was a critical feature that was added and helped keep a carrier fighting during the battle of midway when it should have been lost the first time around.
The tanker exploding is just a part of the ad for the game "Battleship"
Another great video & love your research 😊👍
Thank you Henry.
Who knew Jaime Lannister, the Kingslayer, knew this much about boats...
The last time, it started with a call from the support department. They wanted to know if I had a backdoor tool that could dump the memory from a particular industrial controller without turning it on, because this particular controller had been extracted from Panam Serena, a chemical tanker that had exploded in Porto Torres. Sadly it turned out that our controller had lost power 10 minutes before the bang, so we didn't have sensor data for them, but that also told them something.
everyone from istanbul remebers the 1979 independenta explosion. it was in the middle of the bosphorus, shattered every glass in the town. massive accident.
The LA explosion was ammonium nitrate, which can explode without oxygen. It simply decomposes in an exothermic chain reaction into NO2 and H2O when ignited. This is why it is commonly used for explosives.
Whether it had an inert gas or not would have been irrelevant.
The gas can happily bubble through 🤣🤣 your speaking voice illustrated that very well!
Most oil tankers use the boiler as source of inert gas, not the main engine nor the diesel generator engine.
Very informative
The last time i heard a tanker explode is the collision of MT Vector and MV Doña Paz
Wasn’t the Dona Paz a passenger ferry? Those poor passengers never had a chance.
Do some research on the Halifax Explosion. Largest man-made explosion pre-atomic bomb
Look up ancient India nuclear explosion. And the vetas
nice explanation. just a detail is that engine exhaust is mostly nitrogen
Very very interesting! Thanks for sharing :)
Was watching a documentary about ferries and I felt like I knew a lot of things they were talking about because of watching your channel! 😁
Great video, presumably if the tank was full and there was no space for oxygen to mix with vapours that would also stop an explosion.
0:20 that was so nice of you to include that picture of someone’s parent/sibling/child dying in a video where that isn’t even relevant.
Wtf are you on about
And how are you sure that it's a human manned rocket and not a sattelite one?
Another thing the heavy tankers most people think of leaving the middle East are full of unrefined crude which put off little vapor to begin with and is not explosive
You are very badly mistaken; crude oil is volatile even the heaviest such as the Venezuelan crudes for around the Maracibo Lake contains a small fraction of light elements.
Dude, every Wednesday my tanker explodes. Why? Taco Tuesday....... A day of the week that will live in infamy.
As a chemical engineer we know all to well about this process and why its so important
I remember when the Betelgeuse exploded at Whiddy Island.