Hamburg - International Bunker Industry Association … · Hamburg November 2014. Scope of...
Transcript of Hamburg - International Bunker Industry Association … · Hamburg November 2014. Scope of...
Hamburg
November 2014
Scope of Presentation
• Bunker Claims – Are they on the increase?• Can developments in the Marine Fuel International
Standard help to reduce claims?• Our job is getting more complicated -Investigative testing
procedures• The future
Around 900,000 deliveries each year
• Brookes Bell receive around 150 new cases a year. These tend to be fairly serious cases with engine damage and lost time. Other experts may have cases that we do not see but probably no more than another 150
• The testing houses (DNV/Viswlab etc) suggest that around 10% of all fuels have some quality aspect that does not meet the specification. Many deviations are very minor
• Overall probably less than 0.03% of deliveries result in serious claims but the consequences can be very costly.
Are claim numbers increasing?
• They appear to be increasing slightly• More worrying is the complexity of some
claims due to unusual fuel contamination• The test methods we now have to use to
detect waste products is time consuming and costly and in general they are not approved standard methods.
Types of Problems Encountered
– Purifiers unable to remove contaminants– Excessive sludge in purifiers– Filters Blocking– Sticking of fuel pumps and injectors– Excessive wear / corrosion of injection system
components– Damage to piston rings, Liners and pistons
Excessive Sludge
Choked Filters
Seized Fuel Pump
11
Catalytic fines – in piston rings
Piston failed
Pressures on Quality
• Blending to meet lower sulphur requirements
• Inappropriate selection of blend components
• Low cost blend components• Resulting problems – Stability, Ignition
quality and Contamination• Buyers seeking lowest price in rising
market. Fuel is highest operating cost
Most Charterparties and supply contracts today refer to
ISO 8217 2005
International Fuel Quality Standard ISO 8217
Constantly under review but can it cover ALL quality concerns?
2005
RESIDUAL FUELS ISO 8217:2010
WORDING OF ISO 8217:2010 PARA 5
5 General requirements
5.1 The fuel shall conform to the characteristics and limits given in Table 1 or Table 2, as appropriate, when tested in accordance with the methods specified
5.2 The fuel shall be a homogeneous blend of hydrocarbons derived from petroleum refining. This shall not preclude the incorporation of additives intended to improve some aspects of the fuel's characteristics and performance. The fuel shall be free from both inorganic acids and used lubricating oils
5.3 Fuels shall be free from any material that renders the fuel unacceptable for use in marine applications.
WORDING OF ISO 8217:2010 PARA 55.4 The fuel shall be free from bio-derived materials other than 'de
minimis' levels of FAME (FAME shall be in accordance with the requirements of EN 14214 or ASTM D6751). In the context of this International Standard, “de minimis” means an amount that does not render the fuel unacceptable for use in marine applications. The blending of FAME shall not be allowed. NOTE See Annex A
5.5 The fuel shall not contain any additive at the concentration used in the fuel, or any added substance or chemical waste that
a) jeopardizes the safety of the ship or adversely affects the performance of the machinery; or
b) is harmful to personnel; or
c) contributes overall to additional air pollution.NOTE See Annex B.
WORDING OF ANNEX B OF ISO 8217:2010 – 1DELETERIOUS MATERIALS
This International Standard precludes the incorporation of deleterious materials as stipulated in Clause 5.
Such materials should not be present, mixed or blended in marine fuels.
Determining the harmful level of a material or substance is not straightforward given that
a)each fuel is a unique, complex blend of hydrocarbon species;
b) a wide range of materials from different sources can enter the marine supply chain from the production, handling and transport systems;
c) varying levels of contamination can be present in the fuel due to the use of common equipment or pipelines in refineries, fuel terminals or other supply facilities;.
Limitations of Standards
• They can only provide limits for reasonable quality parameters
• Cannot list all the possible contaminants that could find their way into bunkers
• From time to time “strange” contaminants appear:- Bi-products from industry, polymers, acids etc.
• At the end of the day the bunkers should be fit for use but the International Standards provide a primary bench-mark.
Investigative Analysis of Fuel Quality
Why is it required ?
• The (Table 1 & 2) ISO 8217 test requirements are capable of highlighting fuels of sub-standard quality. However, the scope of these is restricted and many problematic fuels meet the limits set in the International Standard, yet still cause difficulties.
• There is therefore a need to go beyond the routine specification tests to assess whether a fuel might be causative of shipboard problems.
Types of contaminants encountered
These include bi-products from various industries :• Waste Solvents (organic / chlorinated)• Vegetable oil derivatives• Tall-oil from the timber industry• BPA tars from Bis-Phenol A manufacturing• Ethylene cracker residues (a source of styrene & dicyclopentadiene [DCPD]• Organic acids & esters• Polymeric materials (e.g polypropylene, polystyrene, polyacrylate)
Analytical Aims
• To assess whether there is anything untoward about the fuel that is not highlighted by the routine tests, but which might place it in breach of the (Para 5) ‘General Requirements’ of the specification and / or render it unfit for purpose.
• To evaluate a possible link between shipboard problems and fuel abnormalities / contaminants detected.
Where to start and what to look for?
• There is no one all-encompassing analytical technique / or procedure.
• Each incident provides a different analytical challenge and has to be assessed individually on the basis of the type of problems incurred.
• Clues may be provided by the routine test results, but it is essential to have detailed info concerning the symptoms, difficulties and damage encountered.
Combustion Problems Include :Elevated exhaust temperaturesBroken piston ringsLiner Damage
– These may be consequent simply upon fuel handling difficulties (e.g. failure to purify fuel adequately or interference with injection system components).
– And, of course they may also be non-fuel related.– However they can be related directly to fuel quality (e.g.
due to poor ignition quality or excessive levels of ‘slower’ burning constituents).
Analytical Techniques
Various analytical techniques (and supplementary test methods available). Ones commonly employed include : -
• Infra-Red Spectroscopy (FT-IR) • Gas Chromatography (GC) – usually combined with a Mass
Spectrometer as detector (GC-MS) • Microscopy (Optical / Scanning Electron – in combination with
Energy Dispersive X-Ray analysis (SEM /EDX)• Fuel Ignition Quality Analysis
Infrared Spectroscopy• This analytical technique is used to reveal details of the molecular structure of
organic materials.• The technique is based on the fact that atoms within organic molecules are prone
to various forms of vibration. These cause the molecules to absorb specific frequencies of light in the Infra Red region of the electromagnetic spectrum which correspond to the particular vibrational modes of the bonds within the molecules.
• The technique basically entails passing a beam of infrared radiation through a relatively thin layer of the material under test and measuring the amount of radiation absorbed across a range of frequencies, to obtain an infra red spectrum.
• In relation to fuel oil it is used for rudimentary screening purposes. Different marine fuels comprise largely the same type of hydrocarbons and, as such, give rise to very similar I.R. Spectra. However, the technique is relatively sensitive to certain functional groups that occur in for example acids and esters and is therefore useful for identifying fuels with these forms of contamination.
IR SpectraTwo fuel oil spectra superimposed, one showing a strong ester carbonyl band C=O (at 1737 cm -1)
GC-MS Analysis
The GC-MS technique essentially provides a means of separating the volatile components of complex mixture (generally in order of increasing boiling point) and identifying these by comparison of G.C. column retention times and ion fragmentation patterns, generated by the mass spectrometer, with data from known compounds / reference standards.
A typical GC-MS instrument
A typical G.C. Column
Head-space GC-MS
Head-space analysis is particularly suited to looking for more volatile contaminants, such as chlorinated solvents.It is achieved by heating a portion of sample in a sealed vial, and, after stabilisation, drawing-off, or purging, the vapour into the G.C. instrument. The technique has some advantages, but also certain limitations.
Chromatogram from ‘Head-space’ analysis of a residual marine bunker fuel
2.70 4.70 6.70 8.70 10.70 12.70 14.70 16.70 18.70Time0
100
%
210011501 Scan EI+ TIC
1.11e9
13.84
1.86
2.28
5.04
3.42
2.94
4.04
12.38
6.09
5.37
5.71
10.188.68
7.92
7.87
6.76
7.06
8.06
8.19
10.04
9.46
10.71
11.8511.40
11.32
12.44
13.3412.85
15.16
14.72
16.37
15.2216.62
17.52
Butanol
a-Pinene
Direct Injection GC-MS
This technique entails the injection of a diluted portion of fuel directly onto the GC column, usually after precipitation and / or filtration of the asphaltene constituents.Has advantage over head-space technique in that it covers a wider boiling point range and can highlight the presence of contaminants not seen by the head space technique.
GC trace from direct injection of fuel containing components steam cracking operations
4.50 9.50 14.50 19.50 24.50 29.50 34.50 39.50 44.50Time0
100
%
209050602 Scan EI+ TIC
1.89e1013.03
12.18
11.55
10.40
9.758.45
7.514.69
7.29
25.54
15.20
13.18
14.25
24.28
22.9615.48
21.57
20.12
18.5916.94
19.39
20.20
26.74
27.88
28.99
30.05
31.06
32.04
32.99
33.90 34.79
Naphthalene
Methyl Naphthalenes
DCPD
Direct injection GC-MS– of isolated and converted / derivitised components
Direct injection of front–end fraction isolated by vacuum distillate fraction offers alternative to head-space technique.Certain contaminants are not directly amenable to GC-MS analysis and may go unidentified if not isolated and converted to a more easily detectable form first. Organic acids fall into this category. Isolation can be achieved using solid phase extraction cartridges and solvent recovery regimes.Organic acids and phenols are normally converted to ester forms, which are more easily separated and identified by GC-MS.
Chromatogram of fuel acid-extract illustrating ‘Tall oil’ contamination
18.00 20.00 22.00 24.00 26.00 28.00 30.00 32.00 34.00 36.00 38.00Time0
100
%
210011409 Scan EI+ TIC
3.12e1027.83
27.74
25.82
26.65
27.90
30.04
29.68
28.10
28.8029.61
Palmitic acid
Rosin acids
Abietic acid
Oleic acid
GC-MS Pyrolysis / Probe analysis
These techniques are used for examining solid samples.
• Samples are introduced to the instrument by means of a probe and the temperature raised either to a high level very rapidly (pyrolysis), or heated more gradually.
• Using the pyrolysis technique, thermal decomposition products are carried through the G.C. column and separated in the usual manner. The identification of these can provide useful information concerning the nature of particulate contaminants. (In a recent case, the finding of acrylic acid by pyrolysis GC-MS, helped to confirm contamination of a fuel with a polyacrylate polymer.
Microscopy
• Both optical and scanning electron microscopy (SEM) are helpful in identifying the nature solid contaminants isolated from fuel samples, normally by filtration.
• SEM can achieve very high levels of magnification and is particularly useful and when the instrument has EDX (energy dispersive X-ray) analysis capabilities.
• X-rays are emitted when materials are exposed to high energy electron beams and these provide information about the composition, distribution and abundance of elements in the sample.
Photomicrograph of deposit on gauze filter after filtration of toluene-diluted fuel sample.
Field width ~ 20 mm
Same fibrous particles under SEM. Found to be cellulosed based and believed to be cotton fibres.
Magnification x100
Photograph of glass fibre filters from satisfactory Total Potential Sediment test
Under SEM, same filters revealed presence of spherical particles. These appear similar to catalytic fines, but EDX analysis indicated composition mainly carbon & oxygen, and further analysis confirmed a polyacrylate polymer.
Magnification X 500
SEM image of same spherical particles isolated on 38 µm gauze filter
Fuel Ignition Analyser (FIA)
•Constant volume combustion chamber instrumentation was developed by Fueltech (Norway) as an empirical method for assessing ignition and combustion characteristics, and is proferred as an alternative to the CCAI (Calculated Carbon Aromaticity Index).
•The technique involves injecting a sample into a (constant volume) combustion chamber charged with compressed air. Pressure changes within the chamber are recorded and the data used to calculate a series of values, including Ignition Delay (ID), Main Combustion Period (MCP) and Rate of Heat Release ROHR etc.
•The methodology was taken up by the Institute of Petroleum (I.P) and after revision was published as an IP test method in 2006 (IP 541) .
•The method, however, is yet to gain acceptance as a ISO 8217 test requirement and whilst it is viewed as capable of distinguishing differences between fuels in terms of criteria that are relevant to ignition quality, the relationship between data from this and real engine performance has not yet been properly established.
Working Principle
Combustion Pressure Trace
Ignition delayPre combustion
Main combustion
After burning
Rate Of Heat Release - ROHR
Time
Max ROHR time
Max ROHR value
Combustion Energy
Output:Parameters derived from Combustion Pressure Trace and Rate of Heat Release (ROHR)
Case: Problem fuel• Fuel properties according
to ISO 8217• Caused extensive
problems for main engine– Reduced engine output– Heavy knocking at part
load– Cylinder components
needed replacement• FIA testing at Fueltech
shows:– Bad ignition and
combustion properties– Indication of dumb-bell
fuel
ROHR Curves
-0,5
0,0
0,5
1,0
1,5
2,0
0 5 10 15 20 25 30
Time (msec)
ROHR
(bar
/mse
c)
Combustion Pressure Trace
-0,5
0,5
1,5
2,5
3,5
4,5
5,5
6,5
0 5 10 15 20 25 30
Time (msec)
Pres
sure
incr
ease
(bar
)
Normal fuelProblem fuel
Normal fuel`Problem fuel
The future for Marine fuel is uncertain
• Will ships switch to gas oil?
• Will scrubbing become the norm?
• Will LNG be the answer?
• If we continue to use residual fuel and fit scrubbers quality claims will go on much the same
• If we switch to gas oil quality claims will reduce significantly
• If we switch to LNG quality claims should almost disappear. But LNG quality can vary significantly and a marine spec is needed.