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Bunker C 3

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dgappel

Electrical
Mar 25, 2004
2
I am investigating a new diesel/bunker c additive and it application/usefulness in the Russian market. I need stats on the quality of diesel/bunker C currently used in Russia and what % of the market currently use additives to increase performance, to lower costs and to lower emissions. Do anyone know where I obtain this type of info.
 
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I would suggest a query to or on the (International Bunker Industries Association).

Fuel quality is very variable and a problem for the industry whatever the source, especially with the increase in secondary processing.

Russian produced marine fuels have been formulated to different specifications from the rest of the market but they may well be adopting the new international standards (themselves under review) as the seek to increase their export earnings.

Certainly the refiners are taking steps to improve the consistency of the fuels produced by investing in new equipment for the blending process.

Companies such as Viswalab, DNV PS, Lintec, SGS etc are in the business of testing fuel oil samples sent to them e.g. for quality assay following bunkering. This may be the best way to find out what the current real state of affairs is... if they will share this information.

Otherwise FOBAS produce reports on fuel oil quality.

Whether there are specific reports on Russian fuel oils is open to questions.

JMW
 
jmw,

With respect to bunker type fuels, can "consistency" and "fuels" be used in the same sentence??

According to my clients burning heavy fuel oils right now, it is anyone's guess as to what comes off of the barge, and once the lab gets the report back as to what it really is, it is already in the fuel storage tanks, and the only way to remove it is to pump it to the burners and (attempt to) burn it.

There are real problems out there right now.

rmw
 
The problem with consistency of heavy fuel oils, and they have been with us since the 1970's (the fuel crisis resulted in secondary processing; secondary processing means an increasing proportion of heavy fuel oils are a blend and not straight run products: today 65% of fuels out of the ARA ports and Singapore are blended) is that it is currently only in the refinery that the blend quality can be assured (almost always) That's not quote true, some leading independents can now offer far better consistency in barge and terminal blended fuels (see below).

Samples of the feedstocks (residual oil, cutter stock) are analysed and the fuel calculator (obtainable from the oil companies or DNV PS on request) is used to determine the required volume or mass ratio to produce a fuel of the target specification.

Viscosity is an excellent indicator of quality. If the viscosity is right the other parameters will conform to the fuel calculator predictions.

In the refinery the industry standard instrument is the process capillary viscometer. This is not practical for use elsewhere in the marine fuel industry.

In terminals and in barges they blend by controlling the volume flow rate ratio to the value predicted by the calculator. Many of the methods used are vulnerable.

The problem is that the system depends on the integrity of the samples and the accuracy of the blending equipment. Ensuring a representative sample can be a problem; for example, fuel in storage can stratify. This problem also affects the refiners; many blend into storage tanks, take top middle and bottom samples and then calculate any corrections required. In one Siberian refinery they now use modern digital viscometers which allow them to pipeline blend without subsequent correction; obtaining much improved consistency.

If the samples are wrong, the fuel calculation result gives the wrong ratio. Even with the right ratio there are some uncertainties in the accuracy of many mechanical blenders.

These are the problems that beset ethical suppliers who often compensate by adding excess cutter stock (the expensive component) and this excess is referred to as the "give-away" and can vary from around $1-$7 a ton according to estimates.

Chalmers Lindholmen (Sweden) monitored fuel supplied to a vessel over a two year period. It was supposed to be 380cst. It actually varied from 150cSt to 415cSt but mostly was lower viscosity rather than higher.

This does not consider corrupt practise. In order to try and ensure that fuel is correctly supplied bunker surveyors can be retained to witness the blending or transfer of fuel during bunkering.

According to the Singapore authorities some surveyors were earning nearly 5 times salary in bribes when associated with fraudulent fuel supply. The problem can be serious. Fuel is around 70% of the operating cost of a ship.

Without proper instrumentation the parties to the bunker supply are dependent on sample taking and analysis. The results are not available during bunkering but 24-48hrs later by which time the cost of returning to port and re-bunkering are punative and the cost of litigation is also a serious issue.

The instrumentation is now available for refiners, terminals, barges and receiving ships. Many of the problems can be identified and resolved/improved but it is early days yet. So far this equipment is only being used by some independent bunker suppliers. Similar instruments are used with some engines but not on many ships yet.

Some estimates say that as many as 40% of bunker operations are not sampled, though they should be, and of those sampled something like 17% of samples are not sent for test. In many cases the ships engineer can compensate by careful management of the fuel treatment system on board and by relying on the fuel heaters to compensate for excessive viscosity. So this is preferable to discovering you need to go back to port. Chances of fuel out of spec: 1 in 10; of being out enough to damage engiens: 1 in 120... you see the odds.

However, at least one major engine company has been using digital viscometers for fuel heater control for some years now and uses similar instruments to check bunkers as they are delivered. These instruments can inform about density (at operating temp, at 15degC and at 98degC), dynamic and kinematic viscosity (and kinematic viscosity at 100deg C or 50degC), ignition index (CCAI and CII to BS MA 100)and can inform the engineer as he is bunkering the answers to two quesions: "Can i clean it?" and "Can i burn it?".

Without these technologies the option is to depend more and more on refinery controlled quality.
The result of this is only refnery blends will be supplied. This may guiarantee better consistency but may lead to fewer grades available and only from the major ports.
It isn't going to make fuels cheaper.
Already the independant bunker suppliers are fewer. In Rotterdam only the major oil companies now supply fuel, the independents being forced out into the smaller ports.
It may soon not be possible to obtain competitively priced fuels.

The independents can operate from the smaller ports and can buy feedstocks competitively. If they adopt the new technologies they can blend accurately on line in the terminal or on the barge. Some few have already taken these steps.

For them and for the ship owners modern viscometers can enable them to control cosnistency, can enable them to continue to provide fuels from small ports and to exploit availability of lower cost bunkers.

Ship owners and barge operators can see quality as the fuel is delivered.

The solution is there, just very few people have it yet.

Anyone interested in the new methods can see articles in the December 2003 issue of Bunker News, the April 2002 issue of bunker News and various article in Hyrocarbon Engineering in 2000, 2001 and 2002 where they have run articles on viscosity measurement.

JMW
 
jmw,

Boy, I yanked your chain, didn't I?

Good treatise. I think it deserves a star.

rmw
 
Marine fuel is purchased to produce heat for conversion into work. Perhaps the empirical formula to estimate the net specific energy, in MJ/kg, woud serve to show the relevant factors, such as the density at 15oC, d, and the contents of: water, w; ash, a; sulphur, s; present in fuels, expressed as decimals:

net MJ/kg=(46423-8792d2+3170d)[1-(w+a+s)]+9420s-2449w​

As for additives, there are two categories: those which assist to reduce potential problems in pre-combustion (up to the time the fuel is atomized in a burner or injector) and those which react during the post-combustion phase.

An effective additive for the first phase would make a positive contribution to:

1. Dispersion of sludge in storage.
2. Promote water separation in storage.
3. Prevent potential polymerization and sludge formation.
4. Prevent corrosion within fuel lines and tanks.

Such additives have alkaline properties and are based on dispersants, anti-corrosion agents, anti-oxidants, anti-polymerization agents, and emulsion breakers, available as solutions and suspensions in aromatic solvent carriers.

For the post-combustion stage, ash-modifiers are found to be beneficial. Slagging and high-temperature corrosion occur when molten ash adheres to the metal surfaces, and there is a reduction of heat transfer.

Hence, the ash modifier should be able to increase the ash melting point and make it more friable. It is generally an accepted fact that when the ash is not in the molten form it will not be corrosive. Of the numerous ash-modifying chemicals one can mention those based on compounds of aluminium, barium, calcium, magnesium, and silicon. However, incorrect applications, can cause further problems downstream.

Some additives, improperly known as "combustion catalysts" influence burning when present in small quantities. Their function is to inhibit the formation of carbon precursors, causing carbon to be more extensively burnt. These additives can be a single metal or a combination, usually involving transition elements. Iron, magnesium, or their combinations, are commonly used. Dosage is not as critical as with ash-modifiers, and to obtain full effects one should follow the suppliers' instructions. [pipe]
 
It is not just bunker type marine fuels that are having their share of troubles these days, check out the following link to see what the utility industry is struggling with, even with the so-called clean, light distillates, and by extension, to some degree, the automotive fuel sector, as well.


I just made some comments regarding the automotive sector in the engine and fuels thread 71-90606 that were not "technical" in nature, but deal with real life aspects of the overall problem.

I have used, and advocated the use of additives (for heavy fuel oils) in the past, so I am a fan. Unfortunaely, too many in the business are just peddling "snake oil" and additives get a bad name, so the good ones don't get the scrutiny they need.

When the remedy is calling someone to "dynamite" your boiler because the clinkers are so big, ash fusion temperature modification is a real world topic. And, the only thing that can do that is ash content modification in the fuel itself, or the use of a good additive to handle the ash that is there.

25362, your comments on this matter merit a star, because they are very informative, and comprehensive.

rmw
 
I was at a cement works once where the cylinderical rotating kiln had a small cannon mounted at the end and every so often they used this to fire solid projectiles at the clinker.
I was rather surprised at this but not as surprised at their methods to start the kiln up again. They were using heavy fuel oil but started with light fuel ignited with burning oily rags.
These would be thrown in first, the door closed and the fuel turned on. There was a bit of a problem when i was there one day when they got the order reversed and the guy threw the burning oily rags into a shower of fuel. He was lucky just to lose his eyebrows.

JMW
 
Hi, I think that I am going to change the thread a little. I am actually based in the region (the Former Soviet Union), where the industry continues to be very tightly government controlled. For each and every product we have a range of specifications which must be followed. If you (or anyone else) wants to send me an e-mail address, then I will send you back the specifications for the principal products. On the other hand you talk of "increasing performance" and "lower emissions", neither of which tend to be priorities out here. Costs because Fuel oil is very cheap (in the days of Communism it used to be free), and environment, because this does not make money, and there are few motivators to make it better. Concerning specifications, the FSU is way behind the West. Heating Fuel Diesel can contain up to 1.1% Sulphur, whilst motor vehicles can run up to 0.5%. Fuel Oil sulphur can still run up to 3.5%, whilst there is no specification for stability for Fuel Oils. To answer the last part of your message, I am not aware of additives being used in the refining industry. Frankly, I would think that equipment upgrades are a higher focus than additives.
Jeffrey.Temple@Petrokazakhstan.com
 
I meant to aknowledge the excellent post by 25362 also, and an interesting link.

Additives have come up before in these threads (often viewed with some suspicion).
I was looking for one link particularly thread71-81847 where the link posted there comes from yet another thread id didn't have time to locate.

KazakJeff,
One of the refineries I visited in Southern Siberia (about 100square kilometers and 20% of its output is heavy fuel oil) is supplying power stations throughout the old Soviet Union.

As you suggest, upgrading equipment is a significant factor. The need for quality improvement wasn't about specification, which remained whatever the required standard is, but about consistency which was ass much a problem for them and the internal market as RMW correctly observes it is for the market in general.

However, this and the high level of rejection through not meeting those specifications was not the only concern; another factor is the need for operators to climb the storage tanks and take top, middle and bottom samples on a regular basis which is a tough and dangerous job when 6 months of the year, the temperature is below freezing (it ws 30deg below the last time i was there).

Despite the excellent laboratory testing, the problem they faced was the same as most refineries face, the lack of good process measurement. Whatever the standard, the ability to meet it is difficult even in the refineries.

However, Russian produced bunkers are increasingly available on the global market and the bunker facilities in a variety of ports in the former Soviet Union are increasingly available. (St Petersburg is prominent among them and a host to international bunker conferences. I imagine many of the bunkers supplied from St Petersburg derive from the nearby Kirishi refinery?) and there is evidence of blending to meet "international" specifications. International increasingly means the ISO 8217 specification though many refineries still blend to local specifications.

One of the major concerns now is the low sulphur requirement increasingly imposed from outside e.g. European and US legsilation which is to be enforced in some waters. The low sulphur spec will add around $65 a ton initially, dropping to around $35 a ton as low sulphur stock becomes more available. (Current price typically around $154 a ton).

PS KazakJeff, the site moderators are going to warn you about piblishing your e-mail address on the site, it's a great invitation to spammers.





JMW
 
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