6. biodiesel quality adjustment by additives and anti-oxidants apec biodiesel/1st apec... ·...
TRANSCRIPT
Biodiesel quality adjustments by additives and anti-oxidants
APEC Biodiesel Standard
Raoul [email protected]
In co-operation with HART ENERGY CONSULTINGwww.hartenergyconsulting.com
25 October 2007
Biodiesel vs Petroleum
� Biodiesel (FAME) DIFFERENT (to petroleum)� Chemistry is fundamentally different, so properties,
performance & durability differences follow
� So, risk for vehicles and vehicle technology of today� Biodiesel supply limited and growing slowly
� so vehicles are designed for conventional� modified or passed for biofuels with restrictions
� Biodiesel standards are driven towards conventional diesel standards, ie. Performance� Coming from older standards base as vegetable oils
� Requires specific standards for � Biodiesel – feedstock & process dependent� BlendsAND ADDITIVES CAN ADDRESS
�Definition: � “Agents that are added to fuels in a concentration of <
1% �Substances present in higher concentration, the term "fuel
components" is more appropriate.”
�Fuel additive categories:�Multifunctional Diesel - market performance�Refinery Specification Additives�Anti-Oxidant and Stability Control Additives
�Additives may be designed for petroleum based fuels or increasingly are specifically modified for use with Bio-Fuel components
Additives
� Changing fuel parameters can cause unforeseen wear, deposit or combustion problems with corresponding impacts on engine performance and emissions
� Fuel additives can selectively restore specific performance characteristics of the fuel
� Test methods & standards can be established that correlate to long-term performance given sufficient time and data� Environmental concerns led to the introduction of Ultra Low Sulphur City
Diesel in Sweden in 1991 and a subsequent rapid increase of fuel injection equipment (FIE) failures
� rapid introduction of lubricity additives provided the solution….classic example of a reactive approach
� lubricity additive experience in Europe and correlation exercises with fuel pump wear have shown the HFRR test with a 460µm WSD to be a reliable and appropriate level to protect current fuel injection systems and on which to develop future systems
Additives: Effect & Need
Biodiesel performance issues�Low temperature operability – DIFFICULT TO ADDRESS
�Elastomer compatability – NOT GENERALLY ADRESSED BY ADDITIVES
�FIE (Fuel Injector Equipment) component compatability – METAL DEACTIVATORS & STABILITY
�Deposit formation & storage stability – ADDRESS�Engine oil dilution- NOT GENERALLY ADRESSED BY ADDITIVES
�Exhaust (tailpipe) emissions – NO HARM
� Lubricity – NOT NEEDED
�Conductivity – ONLY FOR BLENDS
�Cetane Number – MAYBE ONLY FOR BLENDS
�Foaming – ONLY FOR BLENDS
Additives: Biodiesel Issues
The temperature at which pure (B100) biodiesel starts to gel varies significantly depending on the mix of esters and therefore the feedstock oil used to produce the biodiesel
� low erucic acid RME starts to gel at -10 °C
� biodiesel from tallow gels at +16 °C
There are a very limited number of products that will significantly lower the gel point of B100 biodiesel, particularly for high molecular mass biodiesels
Coldflow Additives for Biodiesel
Coldflow : RME with different diesels
Coldflow : RME vs SME blends
Coldflow Additives Effect: B100
Coldflow Additives : Treat rate
Coldflow Additives Effect
� unsaturated fatty acid (feedstock dependent)
� loss of hydrogen >>> free radical
� free radical >>> fatty acid peroxide radical
� fatty acid peroxide >>> hydroperoxide
� hydroperoxide >>> aldehydes, ketones
this process can be halted by an antioxidant converting the original free radical back to the fatty acid by donating hydrogen
Stability and Oxidation
oxidation will be catalysed by trace metals
� metal deactivator prevents this
Different fatty acid chemistries may respond better to different AO chemistries
� formulated AO including mixed chemistries give a wider spectrum of protection
Stability and Oxidation
Anti-oxidants effective: Differences
Stability and Oxidation
Test Fuel: Commercial diesel fuel blended the FAME meets EN14214 by 5vol%
Test Fuel: Same FAME above with 400ppm of anti-oxidant (20ppm as B5)
Anti-oxidant additives effective
Ref: JAMA
Tests
2nd Japan/Korea Petroleum Technology Seminar, October 24, 2006 in SEOUL, KOREA
Anti-oxidant additives effective
Ref: JAMA
Tests
Anti-oxidant additives effective
Ref: JAMA
Tests
ASTM Working Group� Significant additional work is planned � Test method precision and comparison
� Rancimat and D 2274 � Ability of each method to predict benefits of anti-oxidants in reducing
sediments and deposits
� Comparison of bench scale results to actual field operations with B20 and lower blends
� Determination if control of B100 stability is sufficient for all blend levels with all petrodiesel
� Control at the B100 level is preferred � Anti Anti-oxidants are most easily added to B100 � Blending is done at terminal
� Monitor acid number as surrogate for stability
Oxidation Standard Development
Detergency of Biodiesel
� Biodiesel presents challenges for the automotive industry
� A need to define performance standards that ensure acceptable quality and operation of bio-fuels in the market place
� Fuel additives provide the only solutions for some performance issues that are faced by bio-fuels� Anti- oxidants for stability (rather than Iodine Number)� Cold flow improvers for low temperature use� Rest are occasional or specific market use of additives
� Standards need to be developed based on performance criteria to ensure that the full benefits of fuel additives are realised.
Summary
THANK YOU
APEC Biodiesel Standard
Raoul [email protected]
In co-operation with HART ENERGY CONSULTINGwww.hartenergyconsulting.com
25 October 2007
Biodiesel additive development opportunities
APEC Biodiesel Standard
Raoul [email protected]
In co-operation with HART ENERGY CONSULTINGwww.hartenergyconsulting.com
25 October 2007