diesel fuel quality - platts · pdf fileen 590:2013 • the 1st edition 1993 •...

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 1

Contents Drivers for specifications

Challenge of seeking correlations

Views of automotive technology

Biofuels

Conclusions


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

Specification drivers


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


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


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)


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





Biofuels

Conclusions


9

User demand versus Fuel properties Real life requirements Correlation Immediate, e.g. • cold start • cold operability • fuel consumption

Durability, reliability, e.g. • fuel injection system • catalyst, particulate filter • deposits, corrosion

Fuel specification EN 590:2013 Limit values e.g. for • cetane number • cloud point, CFPP, quality of bio, water • energy content (not specified), density

Limit values e.g. for • lubricity, contaminants • ash, sulfur • quality of bio, stability, (additives)

January 30-31, 2014 Diesel fuel quality drivers and issues

10

Society versus Fuel properties Environment, health Correlation • SOx emissions

• NOx emissions

• particulate emissions • catalyst operation • life cycle GHG Renewable feedstocks

Directive 2009/30/EC “FQD” • sulfur • cetane, polyaromatics • sulfur, 95% point, polyarom., density • “sulfur-free” • GHG reduction, bioenergy (2009/28/EC) Directive 2009/28/EC “RED” • sustainability • land use • labor values • etc.


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

Laboratory measurements • rapid for daily quality control • cheap (n x 10 ... 100 €) • accurate • EN xxxxx, ISO xxxxx -methods

• sulfur, aromatics, ... (chem.) • density, viscosity, ... (phys.)

R&D facilities of vehicle companies, Labs of refineries, terminals, customs some oil companies, JRC, ...

11 January 30-31, 2014 Diesel fuel quality drivers and issues

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


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 January 30-31, 2014 Diesel fuel quality drivers and issues 13

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





Biofuels

Conclusions


16

Evolution of engines and diesel fuels

1995 2000 2005 2010 2015 2020

Sulfur 500 mg/kg

350 mg/kg

50 mg/kg

10 mg/kg High

er q

ualit

y fu

els,

e.g

. low

er su

lfur

M

ore

dem

andi

ng e

ngin

es

Euro II

Euro III

Euro IV Oxicatalysts

Euro V DPFs Euro VI

Durability

Helping to reduce exhaust emissions

Enabling exhaust aftertreatment

Operability Lifetime durability

Main fuel quality driver

Euro X = exhaust regulation on trucks and buses DPF = diesel particulate filter


17

Evolution of engines and diesel fuels

1995 2000 2005 2010 2015 2020

Sulfur 500 mg/kg

350 mg/kg

50 mg/kg

10 mg/kg High

er q

ualit

y fu

els,

e.g

. low

er su

lfur

M

ore

dem

andi

ng e

ngin

es

Euro II

Euro III

Euro IV Oxicatalysts

Euro V DPFs Euro VI

Durability

Helping to reduce exhaust emissions

Enabling exhaust aftertreatment

Operability Lifetime durability

Main fuel quality driver

FAME = biodiesel HVO = hydrotreated vegetable oil Euro X = exhaust regulation on trucks and buses DPF = diesel particulate filter

Fossil hydrocarbons ≈ ok Biobased part = ???


HVO

18

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,... => fossil fuel part ok • gasoline sulfur, aromatics, olefins, benzene,... => fossil fuel part ok

Worried about lifetime, durability, need for extra maintenance • diesel

– engine oil dilution FAME and high boiling fractions suspected – ash, P, metals FAME suspected – stability, deposits mainly FAME suspected

• gasoline – metallic octane boosters any MMT or ferrocene strictly forbidden – methanol not a desired blending component


19

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





Biofuels

Conclusions


Biocomponents in EN 590 diesel fuel

Diesel fuel

with FAME Diesel fuel with HVO

Storage stability Challenge Like fossil diesel Cold operability Challenge Excellent (- 40⁰C) Engine & fuel system deposits Challenge Like fossil diesel Engine oil functioning Challenge Like fossil diesel Exhaust system functioning Challenge Like fossil diesel Water pick up from logistics Challenge Like fossil diesel Bacteria growth risk Challenge Like fossil diesel Pipelines (jet fuel contamination risk) Challenge Like fossil diesel Maximum in EN 590 fuel (vol-%) 7.0 % No limit, “drop-in” Energy content as 100 % (MJ/l) 32.7 34.4


No need to be worried about extra challenges with bio when HVO used • in fuel logistics • in vehicles

Blending value of HVO


Fossil base fuel

HVO 70 % base fuel + 30 % HVO

Effect of HVO in EN 590 blending

Density (kg/m3) 837 780 820 Base fuel can be > 845 Cetane 55 88 65 Base fuel can be < 51 Polyarom. (%) 1.1 < 0.1 ≈ 1 Base fuel can be > 8 Sulfur (mg/kg) 3.6 ≈ 1 ≈ 3 Base fuel can be > 10 Ox. stab. (g/m3) ≤ 25 ≤ 25 ≤ 25 No effect Viscosity (mm2/s) 3.6 3.0 3.4 No remarkable effect Water (mg/kg) 20 20 20 No effect Ash (%) 0.001 0.001 0.001 No effect Metals (mg/kg) ~ 0 ~ 0 ~ 0 No effect Distill. 95 % (⁰C) 360 298 355 Base fuel can be > 360 Cloud point (⁰C) -1 -11 -3 -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




Biofuels

Conclusions


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



Thank you for your attention

diesel fuel quality - platts · pdf fileen 590:2013 • the 1st edition 1993 •...

Documents