Diesel fuel quality drivers and issues Platt’s 4th Annual Middle Distillates Conference January 30 - 31, 2014, Antwerp, Belgium Seppo Mikkonen Neste Oil
[email protected] January 30-31, 2014
Diesel fuel quality drivers and issues
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Contents Drivers for specifications Challenge of seeking correlations Views of automotive technology Biofuels Conclusions January 30-31, 2014
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Specification drivers 1. Legislated • •
European directives, regulations national regulations
2. Standardized • • •
prepared by technical experts in CEN Working Groups – oil industry, automotive industry, biofuel industry people commented and balloted by national standard bodies (EU + other European countries) in principle voluntary since not prepared by authorities and not formally accepted by political processes – however, some countries have mandated fuels to meet standards
3. Fit for purpose • •
cars, vans, trucks, buses, non-road mobile machinery, vessels different climatic conditions
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1. Legislated Directive 2009/30/EC “FQD” •
•
exhaust emissions related properties – minimum cetane number – maximum density, 95 % point, polyaromatics, sulfur, biodiesel (FAME), MMT – free use of renewable hydrocarbons (HVO, BTL) – in force at retail points where vehicles refueled minimum GHG reduction; can be pooled between batches and suppliers
Directive 2009/28/EC “RED” •
minimum bioenergy content; can be pooled between batches and suppliers
Other regulations • •
minimum flash point for safety distillation points in custom’s CN codes
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2. Standardized EN 590:2013 • •
•
•
requirements from FQD and regulations copied 1:1 vehicle operability and durability related limits – cetane index, carbon residue, ash, water, contamination, copper corrosion, oxidation stability, lubricity, viscosity, distillation, cloud point, CFPP – free use of HVO and co-feed as biocomponents , GTL as fossil component provided that final blend meets EN 590 in force at retail points where vehicles refueled – if not met, warranties of vehicles not in force, shortened vehicle service intervals may be required vehicle owner has to trust on quality since he can not analyze fuel by himself
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EN 590:2013 • •
•
•
the 1st edition 1993 frequent updates prepared by oil, automotive and biofuels industry – most oil companies represented in CEN Diesel Working Group – oil industry association Concawe prepares oil companies’ common position use the latest edition – benefits also for refiners and blenders • e.g. fast cetane method EN 15195 “DCN” from 2009 but some customers require the slow and inaccurate EN ISO 5165 cetane engine result challenges – updating 20 years: original relevance of some limit values may be out of date – getting compromises not easy between industries and all European countries – keeping technical specifications as CEN’s decisions (outside political process)
January 30-31, 2014
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3. Fit for purpose Logistics • •
e.g. not contaminating pipelines with biodiesel if pipelines used also for aviation fuels corrosion protection
Vehicles cold operability engine oil dilution by fuel protection for injector fouling, fuel system deposits, corrosion exhaust aftertreatment system lifetime automotive manufacturers published “Worldwide Fuel Charter” (latest edition 2013) – justifies requirements of new sophisticated engines – more forward looking than CEN building compromises (but too stringent?) • vehicle owner wants trouble-free operation => quality assurance: refinery -> terminals -> logistics -> service stations -> vehicles
• • • • •
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Contents Drivers for specifications Challenge of seeking correlations Views of automotive technology Biofuels Conclusions January 30-31, 2014
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User demand versus Fuel properties Real life requirements
Correlation
Fuel specification EN 590:2013
Immediate, e.g. • cold start • cold operability • fuel consumption
Limit values e.g. for • cetane number • cloud point, CFPP, quality of bio, water • energy content (not specified), density
Durability, reliability, e.g. • fuel injection system • catalyst, particulate filter • deposits, corrosion
Limit values e.g. for • lubricity, contaminants • ash, sulfur • quality of bio, stability, (additives)
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Society versus Fuel properties Environment, health • • • • •
SOx emissions NOx emissions particulate emissions catalyst operation life cycle GHG
Renewable feedstocks
Correlation
Directive 2009/30/EC “FQD” • • • • •
Directive 2009/28/EC “RED” • • • •
January 30-31, 2014
sulfur cetane, polyaromatics sulfur, 95% point, polyarom., density “sulfur-free” GHG reduction, bioenergy (2009/28/EC)
sustainability land use labor values etc.
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Seeking correlation Vehicle and engine tests • • • •
Correlation
time consuming (days, months) expensive (n x 10 000 ... 100 000 €) often not accurate, different vehicles often ”in-house” methods
R&D facilities of vehicle companies, some oil companies, JRC, ... January 30-31, 2014
Laboratory measurements • • • •
rapid for daily quality control cheap (n x 10 ... 100 €) accurate EN xxxxx, ISO xxxxx -methods • sulfur, aromatics, ... (chem.) • density, viscosity, ... (phys.)
Labs of refineries, terminals, customs
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Some correlations lost? E.g. cold operability •
•
CFPP versus vehicle cold operability correlation created during 1960 ... 1970’s; since then – lower fuel aromatics: higher risk for wax settling when stored below cloud point – advanced cold flow additives respond well in CFPP test but maybe not in vehicles – FAME: impurities may precipitate even above diesel fuel’s cloud point – new sophisticated vehicle fuel system designs – private diesel cars with low monthly mileage • more time for wax settling before refueling, cloud point sensitiveness cloud point and CFPP tests developed for fossil fuels decades ago – too short exposure time for estimating precipitations in real life today • wax • e.g. saturated monoglycerides originating from FAME => fuel may meet EN 590 but is not fit for purpose in some vehicles
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How to fix cold operability •
•
•
co-operate with automotive companies for designing vehicles for better cold operability – e.g. fuel with -6 ⁰C cloud point and -18⁰C CFPP – car A stopped at -14⁰C – car B stopped at -25⁰C • car B has a larger fuel filter than car A – better designed vehicles would avoid requirements for further enhanced cloud points and CFPPs – good cold operability common interest for fuel and automotive companies sell premium cold operability fuel for cars, standard fuel for trucks – allows higher average diesel cloud point and higher diesel fuel yield at refineries – used in Finland use HVO instead of FAME
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Some correlations lost? E.g. oxidation stability, storage stability • • •
•
methods and limits traditional knowledge from fossil fuels and old vehicle designs finding correlation between real trouble-free operability and fuel specification limit values very laborious today – high fuel temperatures in vehicle fuel systems (above +100 ⁰C) – FAME – no compromise yet in CEN what method and limit satisfactory for vehicles long storage times in some applications – parked combined harvesters, emergency generators, lifeboats, ...
Every limit value in fuel specification should correlate to fit for purpose • •
limits stringent enough for vehicle operability and durability limits not more stringent than needed since extra cost for refineries
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Contents Drivers for specifications Challenge of seeking correlations Views of automotive technology Biofuels Conclusions January 30-31, 2014
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Evolution of engines and diesel fuels Main fuel quality driver
More demanding engines
Higher quality fuels, e.g. lower sulfur
Helping to reduce exhaust emissions
Enabling exhaust aftertreatment
Operability Lifetime durability
Euro II Sulfur 500 mg/kg
Euro III 350 mg/kg
Euro IV Oxicatalysts 50 mg/kg
Euro V DPFs
Euro VI Durability
10 mg/kg
1995
2000
2005
Euro X = exhaust regulation on trucks and buses January 30-31, 2014
2010
2015
2020
DPF = diesel particulate filter
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Evolution of engines and diesel fuels Main fuel quality driver
More demanding engines
Higher quality fuels, e.g. lower sulfur
Helping to reduce exhaust emissions
Enabling exhaust aftertreatment
Fossil hydrocarbons ≈ ok Biobased part = ???
Euro II Sulfur 500 mg/kg
Operability Lifetime durability
Euro III 350 mg/kg
Euro IV Oxicatalysts 50 mg/kg
Euro V DPFs
Euro VI Durability
10 mg/kg
HVO
1995
2000
2005
2010
2015
2020
FAME = biodiesel HVO = hydrotreated vegetable oil Euro X = exhaust regulation on trucks and buses DPF = diesel particulate filter January 30-31, 2014
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Views of automotive companies Stringent regulation for exhaust system lifetime • •
cars min. 160 000 km trucks min. 300 000 ... 700 000 km (km depends on truck size)
Not much worried about • •
diesel sulfur, polyaromatics, density,... gasoline sulfur, aromatics, olefins, benzene,...
=> fossil fuel part ok => fossil fuel part ok
Worried about lifetime, durability, need for extra maintenance •
•
diesel – engine oil dilution – ash, P, metals – stability, deposits gasoline – metallic octane boosters – methanol
January 30-31, 2014
FAME and high boiling fractions suspected FAME suspected mainly FAME suspected any MMT or ferrocene strictly forbidden not a desired blending component
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Views of automotive world Diesel cars •
•
favoured in middle and large cars because of stringent CO2 regulation – average max. 130 gCO2/km in 2015, 95 gCO2/km in 2020 – gasoline preferred only in small cars => gasoline volumes decline sophisticated engines and exhaust systems more sensitive for fuel quality than before – even max. 7 % FAME challenging (some FAME was quite ok for older designs) • engine oil dilution and deterioration • cold operability, fuel system deposits
Trucks and buses • •
more robust engines than in cars due long life time requirements could be designed for 20 % or 30 % FAME (however not preferred) – exhaust system life time: sensitive for lubricant and fuel ash and metals
=> Worth for considering two separate fuel grades? • •
premium for cars (less FAME or FAME-free, better cold properties) standard for trucks and buses
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Contents Drivers for specifications Challenge of seeking correlations Views of automotive technology Biofuels Conclusions January 30-31, 2014
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Biocomponents in EN 590 diesel fuel Storage stability Cold operability Engine & fuel system deposits Engine oil functioning Exhaust system functioning Water pick up from logistics Bacteria growth risk Pipelines (jet fuel contamination risk) Maximum in EN 590 fuel (vol-%) Energy content as 100 % (MJ/l)
Diesel fuel with FAME Challenge Challenge Challenge Challenge Challenge Challenge Challenge Challenge 7.0 % 32.7
Diesel fuel with HVO Like fossil diesel Excellent (- 40⁰C) Like fossil diesel Like fossil diesel Like fossil diesel Like fossil diesel Like fossil diesel Like fossil diesel No limit, “drop-in” 34.4
No need to be worried about extra challenges with bio when HVO used • in fuel logistics • in vehicles January 30-31, 2014
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Blending value of HVO Density (kg/m3) Cetane Polyarom. (%) Sulfur (mg/kg) Ox. stab. (g/m3) Viscosity (mm2/s) Water (mg/kg) Ash (%) Metals (mg/kg) Distill. 95 % (⁰C) Cloud point (⁰C)
Fossil base fuel
HVO
70 % base fuel + 30 % HVO
837 55 1.1 3.6 ≤ 25 3.6 20 0.001 ~0 360 -1
780 88 < 0.1 ≈1 ≤ 25 3.0 20 0.001 ~0 298 -11
820 65 ≈1 ≈3 ≤ 25 3.4 20 0.001 ~0 355 -3
Effect of HVO in EN 590 blending Base fuel can be > 845 Base fuel can be < 51 Base fuel can be > 8 Base fuel can be > 10 No effect No remarkable effect No effect No effect No effect Base fuel can be > 360 -40 possible with HVO
Fossil base fuel does not need to meet EN 590 when HVO blended • economic and volumetric benefit for refineries and blenders Fossil base fuel has to be even better than EN 590 (density < 842) when FAME blended January 30-31, 2014
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Contents Drivers for specifications Challenge of seeking correlations Views of automotive technology Biofuels Conclusions January 30-31, 2014
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Conclusions Vehicle markets • •
share of diesel cars will be high in Europe diesel practically the only one for trucks (some LNG might come?) => mismatch continues in gasoline/diesel markets/refining volumes
Evolution of fuels and vehicles • •
•
•
evolution of fossil fuel successful, no demand for more stringent specifications future vehicles at least as demanding as the current regarding fuel quality – challenges mainly related to FAME as a blending component – HVO preferred by automotive industry updating of EN 590 quite slow for meeting fit for purpose requirements – some test methods and limit values made for fossil fuels and older vehicle technologies, may not be relevant with biocomponents or for modern vehicles – finding correlations between fuel limit values and fit for purpose very laborious retail customers need high quality fit for purpose fuels
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Thank you for your attention January 30-31, 2014
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