7 FUEL - CHARACTERISTICS Density Typical value : 940 kg/m3 to 991 kg/m3 Influence : Measurement of fuel - Specific fuel consumption Centrifuging efficiency Indicates fuel ignition quality (when fuel viscosity is known) Viscosity Typical value : 160 cst to 730 cst Influence : Fuel handling - unloading, pumping, separating Fuel handling - heat input - auxiliary consumption Maximum temperature limitations Fuel atomization Loading on fuel injection equipments, camshaft Indicates fuel ignition quality (when fuel density is known)
8 FUEL - CHARACTERISTICS Ash Non-combustible, un burnt inorganic material Consists of iron, vanadium, sodium, nickel,aluminium, silicon, zinc Max. permissible - 0.2% by mass Influence : Vanadium & Sodium cause hot corrosionhot corrosion Most affected parts - exhaust valve, piston crown,valve guide Carbon residue Carbon content in fuel - left out after complete combustion of fuel. Max. permissible - 22% wt. Influence : Fouling & deposits on piston crown, exhaust passages, turbocharger nozzle ring Faster deterioration of lubricating oil.
9 Fuel – Sulphur effect Cold Corrosion Cold corrosion by formation of sulphuric acid S+O 2 +2H 2 O = H 2 SO 4 +H 2 Piston Ring Surface Temperature Most affected parts - cylinder liner, inlet valve, valve guide Accelerates hot corrosion Faster depletion of lube oil TBN Less calorific value - high fuel consumption
10 FUEL - CHARACTERISTICS Ashphaltenes Highly aromatic hydrocarbon molecules High Carbon-Hydrogen ratio, High molecular weight Very poor ignition quality - longer ignition time Occurs in fuel due to - Incompatibility caused by blending residual fuel with distillate fuel. Excessive sludge - Fuel loss Large size particles will not completely vaporize, leading to incomplete combustion Deposits in engine exhaust ducts, nozzle ring and rotor blades Restricted exhaust gas flow due to deposits and leads to under performance of turbocharger and vibrations Major Effect - High fuel consumption
11 FUEL - CHARACTERISTICS Aluminium & Silicon Highly abrasive Max. permissible - Al+Si – 80/ 30 ppm Influence : Abrasive wear of piston rings, piston ring grooves, cylinder linersAbrasive wear Abrasive wear - mostly on fuel injection pump elements, fuel injector nozzles. Water Water normally comes during handling &transportation Max. permissible - 1% in storage & 0.3% at engine inlet Lower calorific value of fuel Cavitations in pumps Vapour lock in system, pressure fluctuation Fuel ignition quality Larger ignition delay Sudden pressure rise - excess loading Late burning
15 Sulphur in Fuel For every 1 % increase of sulphur in the fuel you loose 1 % in net heat value : 2.1 g/kWh EXAMPLE: Output5000 kW Operating hours per year6000 h Fuel consumption0.0021 kg/kWh 0.0021 kg/kWh x 5000kW x 6000 = 63,000 kg/year LOSS OF FUEL: 63,000 kg/year
16 Ash in Fuel For every 0.10 % increase of ASH content in the fuel you loose 0.04 MJ/kg in net heat value : 0.21 g/kWh Output5000 kw Operating hours per year6000 h Fuel consumption0.21 g/kWh 0.00021 kg/kWh x 5000kW x 6000 = 6300 kg/year EXAMPLE: LOSS OF FUEL: 6300 kg/year
17 Fuel CharacteristicsUnit Max. Limits RME 180 RMG 380 Density@15 deg Ckg/m3991 991 KV@50 deg Ccst 180 380 Flash pointdeg C60 60 Pour pointdeg C30 30 Carbon residue % 15 15 Ash %wt0.1 0.15 Water % vol 0.5 0.5 Classification of Heavy Fuel ( ISO 8217)
18 Fuel CharacteristicsUnit Max. Limits RME 180 RMG 380 Sulphur% mass4.54.5 TSP % mass 0.1 0.1 Vanadiummg/kg200 300 Sodiummg/kg20 20-50 Aluminium + Siliconmg/kg80 80 CCAI -- 850850-870 Classification of Heavy Fuel ( ISO 8217)
19 Fuel CharacteristicsUnit DMB/DMC (LDO) DMA (HFHSD) Density@15 deg Ckg/m3 900-920 890 KV@40 deg C,maxcst 14 1.5 – 6.0 Flash pointdeg C60 60 Pour pointdeg C 0W/6S -6W/0S Carbon residue % 2.5 0.3 Ash %wt- 0.01 Sulphur % wt 2.0 1.5 Total Sediments % vol 0.1 - Al + Si ppm 25 - Classification of Distillate fuel ( ISO 8217)
20 Revision of annex VI of MARPOL 10 october 2008 Reduction of NOx emissions Tier III stands for : ECAs newbuilds after 2016 IMO also formally accepted « scrubber » technology on a principle of equivalence to the use of low S fuel (EGCS = exhaust gas cleaning system) into a SECA area Global cap 20102012 20152020 2025 4.5 % 1.0 % 0.1 % ( distillate) 1.5 % 3.5 % 0.5 % (90% distillate ?) In october 2008, IMO  has decided to modify sulphur levels in (S)ECAs  and worldwide (2020 or 2025)  IMO : International Maritime Organisation, part of UNO, in charge of preparing future regulations on international maritime traffic  (S)ECA : « (SOx) Emissions Control Area", maritime area where vessels are obliged to burn low S fuels or limit emissions of NOx. ECA areas are adopted by IMO after submission by memberstates showing an environmental benefit (on cost/health criteria)
21 (Sulphur) Emission Control Areas 2 nd SECA North Sea + English Channel started in 2007 1 st SECA Baltic Sea started in 2006 Existing SECAs (2) Possible ECAs (US-Canada) most likely to start 2012 or 2013 ; distance 200 miles from the coast Other : Mediterranean ? Japan ? ???
22 Mid next year ISO should issue the next revision under the pressure of IMO who wants some «improvements» specially on health & safety issues What will change? metal content (Al+Si) 80 ppm 60 ppm HFT (stability) change method H2S = new ! (what level still questionnable ; 2 ppm?) ignition/combustion characteristic (method ?) + some other minor changes When ? Expected mid-2010 Revision of ISO 8217
23 Total Marine Fuels - COP RF - Mai 2008 -- 23 The Sulphur Issue : existing SECA areas 1 st SECA = Baltics > August 2006 2 nd SECA = North Sea + Channel > August 2007 Le Havre Rotterdam Brunsbuttel Dunkerque Immingham Antwerp IMO Glossary IMO = UN agency MARPOL handles pollution of ships Marpol Annexe VI handles air pollution SECA = SOx Emission Control Area %S Global = 4.5%S SEAC = 1.5%S
24 Total Marine Fuels - COP RF - Mai 2008 -- 24 MARPOL Annex VI – Options Option 1 - (theoretically admits fuel or distillate) 1.00% Sulphur in [2012…?] everywhere 0.50% S in [2015…?] everywhere this option means distillate because there will be not enough low S fuel available (~300 Mt fuel 300 Mt gasoil) Option 2 – (best scenario for oil industry) Global S level unchanged = 4.50% But SECAs @ 0.10% in [2012…?] this option means distillate in SECAs (or scrubbers) Option 3 « intermediate » Global S level lower = 3.00% in [2010…?] SECAs lowered to 1.00% in [2010…?] SECAs lowered to 0.50% in [2015…?] Micro-SECAs (in ports) may be established with 0.10% The Sulphur Issue : before London MEPC 57 meeting april 2008