Refinery process
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The document provides a comprehensive overview of the history and processes involved in petroleum refining, highlighting the evolution from early kerosene production to modern complex refineries. It details the types of hydrocarbons present in crude oil and their classifications, as well as various refining processes used to convert crude into valuable products. Additionally, it discusses the economic considerations and configurations of refineries that affect product yields, including atmospheric and vacuum distillation.
Refinery process
- 2. History of Petroleum Refining
- 3. History of Petroleum Refineries • Available in small quantities through natural seepage • Drilling of petroleum from first oil well was in Pennsylvania, US in 1859. • The availability of crude oil in abundant quantities led to the development large scale Simple Distillation units. • Primary product was Kerosene, used for lighting lamps.
- 4. History of Petroleum Refineries • The lowest boiling fraction obtained was straight naptha, primarily used as a solvent • Higher boiling fractions were used as Fuel oils, and lubricants • Development of the IC engine, and subsequently automobile, in the end of 19th Century increased the demand of light petroleum gasoline, and led to advancements in petroleum refining.
- 5. History of Petroleum Refineries • Major landmarks in the development of petroleum refineries have been: – Automobile industry – Increased demand for transportation fuels during WW – Increased demand for jet fuels during 1950’s-60’s – Realisation of adverse impacts on Environment in th 1990’s
- 6. Raw Material: Crude oil • Hydrocarbons made of carbon and H2 atoms • Simplest is having one carbon, and four Hydrogen atoms, called Methane. • Molecules join each other and form long hydrocarbon chains. • Carbon atom has four valence electrons, which can combine with hydrogen in different ways to form Alkanes, Alkenes, Alkynes, and naphthenes.
- 7. Raw Material: Crude oil • Saturated chain molecule: Paraffins – General formula CnH2n – Also known as paraffins – Saturated hydrocarbons as all the four valences of Carbon atoms are taken up by hydrogen atoms. – Chemically most stable – Arrangement of chains of paraffins can be straight(normal) or branched chains(iso) – Naturally occurring paraffins are straight chain, and refinery processes produced branched
- 8. Raw Material: Crude oil • Saturated Cyclo-Comounds – More than four carbon atoms, with a ringed structure – Saturated cyclo compounds are called Naphthenes – Naphthenic crude oils have low potential for manufacture of lube oil, but higher conversion to gasoline fractions.
- 9. Raw Material: Crude oil • Unsaturated ringed Comounds – All available valencies of carbon arent bonded with hydrogen – Double or triple carbon-carbon bond may be formed – Arrangement of carbon atoms is either as chained structure (Olefins) or rings (Aromatics) – Chemically unstable and reactive, good combustion properties – Small volumes found in crude oil, but produced as a result of petroleum refining processes – Simplest Aromatic compound is benzene (C6H6)
- 10. Raw Material: Crude oil • Crude oil composition: – Complex mixure of very long chain hydrocarbon molecules – Broad characterization of crude oil is based on the most prevailent form of HC ie, Praffins, Naphthenes or Aromatics – Small quantities of compounds of sulfur, Nitrogen, and Oxygen are also present – Minute traces of heavy metals like Ni, V, Na,Ar etc decide the quality of refined products
- 11. AGENDA • Feed Stock to products • Refinery Processes • Integration of Process Units
- 12. 0 100 200 300 400 IncreasingBoilingPoint(degC) CRUDE OIL REFINING Main Products Crude Oil to Products LPG PETROL KERO HSD FO Main process - simple distillation C3-C4 C9-C16 C14-C24 >C22 C5-C10 500 Lt Distillate Middle Distillate Heavy ends
- 13. Key Refined Products Key Qualities Octane, Sulfur, Vapour Pressure,Benzene Vapour Pressure C2 & C5 content Sulfur, Cetane, Pour point Distillation,Flash point Viscosity, Pour point, Metals, Cal value Main Applications Domestic & Industrial heating,Transport Transport Aviation, heating, lighting Transport, Power Industries, Power Sea transport LPG PETROL KERO/ATF HSD FO/LSHS Freezing point, Smoke point, Flash NAPHTHA
- 14. DENSITY / API GRAVITY Density is used for: ₋ Weight to volume or vice versa calculations ₋ Checking the consistency of crude supply ₋ Control of refinery operations ₋ Used in various correlations ₋ Also gives a rough indication of type of crude oil API GRAVITY= SP.GR.@ 60/60°F Examples: Water = 10 API Kerosene = 45 API Motor Gasoline = 58 API Natural Gasoline = 75 API Crude oils are categorized based on gravity Light grades : Above 33 degree API Medium grades: 23-33 degree API Heavy grades: up to 22 degree API 141.5 - 131.5
- 15. Crude Oil Quality indicators API gravity Above 50 : Condensate 33 to 50 : Light 24 to 33 : Intermediate Below 24 : Heavy Sulphur Below 0.5% : Low 0.5 %- 1.5% : Medium Above 1.5% : High
- 16. Different crude – different yields Lt Distillate Middle Distillate Heavy ends 0.17 0.18 1.9 2.7 O API 40 33.6 34.2 31.0 % Sulfur
- 17. COMPOSTION OF CRUDE OIL: – LARGE NO. OF DIFFERENT HYDROCARBONS – IMPURITIES SUCH AS ‘S’, N, O2 METALS, ETC. – BOTTOM SEDIMENTS & WATER (BS & W) – SALTS, SUCH AS NACL, MGCL2, ETC. TYPES OF HYDROCARBONS: – PARAFFINS – NAPHTENES – AROMATICS – OLEFINS CRUDE OIL COMPOSITION
- 18. TYPES OF HYDROCARBON • PARAFFINS : - Open chain saturated compounds of C & H having general formula CnH2n+2. – Have great chemical stability. – Two types • n - Paraffins • Iso - Paraffins. – N-Paraffins have low Octane No. & high ignition properties. – Iso-Paraffins have high Octane No.
- 19. TYPES OF HYDROCARBON (Contd…) • NAPHTHENES : – Saturated Cyclic hydrocarbons. – High chemical stability. – General Formula CnH2n. • OLEFINS : – Unsaturated open chain hydrocarbons. – Highly reactive. – Generally formed during cracking / conversion processes.
- 20. TYPES OF HYDROCARBON (Contd…) • AROMATICS : – Unsaturated Cyclic hydrocarbons having general formula CnHn. – Chemically reactive. – Aromatics in Gasoline increases Octane number. – Undesirable in Kerosene because of their tendency to give smoky flame.
- 21. • SULPHUR: – Major impurity and present in elemental form. – Sulfides / oxides of sulfur (H2S, Mercaptans, SO2 etc) generated in refinery processes. – Present as H2S / Mercaptans in LPG, as Sulfur / Mercaptans in Gasoline, Kerosene, ATF and as sulfur in HSD & Residues. – Sweetening Processes (caustic washing, Mercaptan Oxidation) are used to remove these impurities from products. IMPURITIES IN CRUDE OIL
- 22. • NITROGEN : – Present in elemental form and also as oxides of Nitrogen. – Forms Acids and causes corrosion. – Removal is necessary to get on-grade products and secondary units feedstocks. • OXYGEN : – Present in elemental form and also as compounds of Oxygen. – Forms Naphthenic Acids and causes stress corrosion. IMPURITIES IN CRUDE OIL (Contd..)
- 23. • METALS : – Main metals in Crude oil are - Lead, Nickel, Vanadium & Copper. – Present in very small quantity (ppm level), in Crude and gets distributed in various products. – Poison to catalysts even in very small amount. • SALTS : – Are formed during Refining process. – Main salts - NaCL, MgCL2, KCL. – Acids formed from these salts attacks plant equipments and corrosion sets In. IMPURITIES IN CRUDE OIL (Contd..) • SEDIMENTS & WATER: – Sediment: Fine particles of sand clay, volcanic ash,drilling mud, rust, iron sulphide, metals and scale. – Damaging Effects Plugging Abrasion and residual product contamination. – Water causes irregular behaviour in distillation.
- 24. Reid Vapour Pressure (RVP) and Light End Analysis RVP indicates relative Percentage of gaseous and lighter hydrocarbons in crude oil.
- 25. POUR POINT • Indicates relative amount of wax present in crude oil • Is the temperature below which pumping and transportation problems may be encountered • Along with viscosity, is used in pumping and design calculations: WAX CONTENT Normal paraffins above CI6 are solid at somewhat ambient temperatures. These hydrocarbons • Affect the flow behaviour of crude • Affect the product quality of gas oil, VGO and asphalt • Lube manufacture is also dependent on wax content of the crude.
- 26. COMPARISON OF IND. & ME CRUDES QUALITY PROPERTIES UNIT BH KUWAIT ARAB MIX IRN LT. IRN HY. API Gravity @ 150 C --- 38.3 31.2 30.3 34.0 31.1 Pour Point 0 C +30 -17 -15 -12 -6 Wax Content % wt 14.7 4.5 5.6 5.7 4.4 Asphaltenes % wt 0.05 1.3 2.7 0.9 2.0 Total Sulfur % wt 0.2 2.54 2.65 1.4 1.65 Primary Yields Light Distillates % wt 24 14 16 17 16 Middle Distillates % wt 46 36 36 43 36 Residue % wt 30 50 48 40 48
- 27. YIELD PATTERN OF VARIOUS CRUDES (% WT) STREAMS BH KUWAIT DUBAI GAS 0.2 0.3 0.1 LPG 1.1 1.2 2.5 NAPHTHA 23.0 16.0 12.9 KEROSENE 20.5 16.5 15.3 HSD 25.0 18.0 27.2 RCO 30.0 48.0 42.0 LVGO + HVGO 74.0 58.0 52.0 VACUUM DIESEL 3.0 1.0 2.0 VACUUM RESIDUE 23.0 41.0 46.0
- 28. REFINERY CONFIGURATION • Catalytic Cracking, Hydro Cracking, Coking, Reformer, etc are referred to as secondary processing units • Nelson Complexity Index • Captures the proportion of the secondary conversion unit capacities relative to the primary distillation or topping capacity • Typically varies from ~ 2 for Hydro skimming refineries to ~ 5 for Cracking refineries and > 9 for Coking refineries • Refineries with high Nelson Complexity Index have • Flexibility to process wide range of cheap crudes • Capable of achieving higher distillate yields & hence higher value addition
- 29. Yields are dependent on Refinery configuration Relative capital cost (per MMT) 1.0 2.1 3.6 4.3 >9 LPG Naphtha Petrol Kerosene Diesel Heavy ends Fuel & loss
- 30. Typical Refinery economics 26.4 53.4 13.9 117.0 120.0 70.0 30.9 64.1 9.7 0.0 20.0 40.0 60.0 80.0 100.0 120.0 140.0 Light distillate Middle distillate Heavy ends Yield Wt. Avg Price Realization Yield - %wt on crude, Price - % of crude price Avg product price – 104.6 % Crude % Improving yield of value added products is the mantra of any Refinery
- 31. REFINERY CONFIGURATION - TOPPING Separates the crude into petroleum products by Atmospheric Distillation. Topping Refinery produces naphtha but no gasoline LPG Naphtha Jet / Kerosene Diesel / Gas oil Fuel Oil (Atmospheric Residue) CRUDE OIL CDU CrudeDistillationUnit 0 100 200 300 400
- 32. HYDRO SKIMMING REFINERY Refinery equipped with Atmospheric Distillation, Naphtha reforming and necessary treating processes. More complex than topping refinery and produces gasoline LPG Naphtha Jet / Kerosene Low-sulphur Diesel / Gas oil Fuel Oil (Atmospheric Residue) C R U Catalytic Reformer Mogas LPG Mogas Gas Oil Desulphuriser CDU CrudeDistillationUnit 0 100 200 300 400 CRUDE OIL
- 33. CRACKING REFINERY Also has Vacuum Distillation and Catalytic Cracking. Adds complexity to the hydro skimming refinery & converts fuel oil to light and middle distillates LPG Naphtha Jet / Kerosene Low-sulphur Diesel / Gasoil Fuel Oil Component (Vacuum Residue) CDU CrudeDistillationUnit CRUDE OIL C R U Catalytic Reformer Mogas LPG Mogas Gas oil Desulphuriser VDU VacuumDistillation Vacuum Distillate (Vacuum Gasoil, Waxy Distillate) FCCU CatalyticCracker LPG Mogas
- 34. COKING REFINERY Converts the vacuum residue into high value products using Delayed Coker. Adds further complexity to the cracking refinery by high conversion of fuel oil into distillates and petroleum coke (used as power fuel) LPG Naphtha Jet / Kerosene Low-sulphur Diesel / Gasoil Coke CDU CrudeDistillationUnit CRUDE OIL C R U Catalytic Reformer Mogas LPG Mogas Gasoil Desulphuriser VDU VacuumDistillation Vacuum Distillate (Vacuum Gasoil, Waxy Distillate) HCCU Hydrocracker Mogas VLS Diesel Jet Hydrogen Coker LPGLPG
- 35. HYDROCRACKING + RDS REFINERY LPG Naphtha Jet / Kerosene Low-sulphur Diesel / Gasoil Low Sulfur Fuel Oil CDU CrudeDistillationUnit CRUDE OIL C R U Catalytic Reformer Mogas LPG Mogas Gasoil Desulphuriser VDU VacuumDistillation Vacuum Distillate (Vacuum Gasoil, Waxy Distillate) HCCU Hydrocracker LPG Mogas VLS Diesel Jet Hydrogen 0 100 200 300 400 AR/VRDS Adds further complexity to the hydro cracker cracking refinery by high conversion of fuel oil into distillates. Also has Residue Desulfuriser. Produces low sulphur fuels
- 37. Refinery Processes • Crude Distillation • Catalytic Naphtha Reforming • Fluidized Catalytic Cracking • Hydro Processing (DHDS, HCU/LOBS, NHT) • Residue Upgradation (BBU, VRDS, Coking) • MISC – Aromatics, Treatment, MTBE, Merox
- 38. Atmospheric Distillation • First Step in the refining of crude oil • Crude oil is fractionated into sharp cuts in an atmospheric distillation column • These cuts are generally Unstabilized Naphtha, HN, Kero/ATF, Light gas oil, Heavy gas oil • Bottoms of the crude column is known as reduced crude oil • A single or multiple columns could be used for fractionation • Crude is first preheated in preheat exchangers / heaters and then pumped to Crude column
- 39. Atmospheric Distillation • Crude column operates at normally 2-3 Kg/Cm2g pressure • Yield of various products depends on type of crude oil • Products obtained from crude column are known as straight run products / components • Energy intensive process • Maximum distillates recovered in CDU till cracking temperatures at operating pressure
- 40. Crude Distillation Unit Distillation column Gas Naphtha upto 170 C Kerosine upto 270 C Diesel upto 360 C RCO/Atmospheric Residue >360 C CRUDE LPG Heater 370 C 360 C 2.2 ata 110 C 2.0 ata Lt Distillate Middle Distillate Heavy ends
- 41. Typical Product Pattern Product TBP Cuts, 0C Yield wt%, LS (Mumbai High) Yields, %wt HS (AMX) Fuel Gas C1-C2 0.3 0.04 LPG C3-C4 1.5 1.36 Stabilized Naphtha C5-90 16.5 11.58 Heavy Naphtha 90-140 3.3 3.42 Kero/ATF 140-280 23.3 16.67 LGO 150-360 16.1 16.35 HGO 220-415 6.0 8.81 RCO 360+ 33.0 41.77
- 42. Vacuum Distillation • To recover distillates from RCO, vacuum distillation is utilized • By reducing the operating pressure further distillates are recovered at lower than cracking temperatures • Vacuum unit generally prepare feedstock for FCC and Hydrocracking Units • Main distillates from vacuum units are called Vacuum Gas Oil (VGO) • Vacuum column bottom is known as short residue
- 43. VDU Process VDU 10-20 mmHg abs 400-405 Deg C Atmospheric Residue Off gas Vacuum Diesel LVGO HVGO Slops Vacuum Residue Heavy vacuum gas oil
- 44. Typical Product Pattern Product TBP Cuts, 0C Yield wt%, LS (Mumbai High) Yields, %wt HS (AMX) Off Gas C1-C2 0.4 0.5 Vacuum Diesel 200-360 11.5 7.8 Vacuum Gas Oil 320-580 78.1 48.1 Slops 500-650 0.0 6.0 Short Residue 580+ 10.0 37.6
- 45. Catalytic Naphtha Reforming • Cat Reforming produces high octane reformate (gasoline) or aromatics raw material for further downstream processing • By products are H2 and LPG • Accomplished in H2 atmosphere at elevated temperature & pressure in presence of a PT- Rh catalyst
- 46. CRU Process CRU 505-535 Deg C 22-23 kg/cm2g Hydrotreated Naphtha H2 rich gas Fuel Gas LPG Reformate
- 47. Typical Yield Parameter MS Mode Aromatic Mode Naphtha Feed Heavier Lighter H2 rich gases 6.5 10.1 Fuel gas 1.2 1.6 LPG 1.9 4.1 Reformate 90.3 84.3 Reformate RON 92 95
- 48. FCC • Purpose of FCC unit is to convert the low value vacuum gas oils to high value products such as LPG and Gasoline • VGO is catalytically cracked to lighter molecules • Most profitable unit in the refinery
- 49. FCC • FCC “heart” of a modern Refinery – Nearly every major fuels refinery has an FCCU • One of the most important & sophisticated contributions to petroleum refining technology • Capacity usually 25% to 35% of the crude distillation capacity • Contributes the highest volume to the gasoline pool (35-40%)
- 50. FCC Process FCC Vacuum Gas Oil Fuel gas Cracked LPG Gasoline Light Cycle Oil Heavy Cycle Oil Slurry Recycle Clarified Oil
- 51. Fluid Catalytic Cracking unit Regenerator Stripper Riser Air Vapors to fractionator Flue gases to Co-boiler VGO Steam P-1.7-2.1 bar T-700 C P-2.0 bar T-495 to 515 C Reaction C30 C-C-C + C-C-C-C-C + C-C-C-C + C8 +C 10 Catalyst T-685 C
- 52. Typical Product Pattern Product TBP Cuts, 0C Yield wt%, LS (Mumbai High) Yields, %wt HS (Kuwait) Fuel Gas C1-C2 1.85 2.52 LPG C3-C4 20.0 15.19 Gasoline C5-180 41.6 41.61 Light Cycle Oil 180-360 16.22 18.36 Heavy Cycle Oil 220-415 12.46 14.46 Clarified Oil 415+ 3.7 3.55 Coke 4.17 4.31
- 53. Hydroprocessing • Hydrotreating – Removal of hetero atoms & saturation of carbon-carbon bonds • Nitrogen, oxygen & metals removed • Olefinic & aromatic bonds saturated – Reduce average molecular weight & produce higher yields of fuel products • Hydrodesulfurization – Remove sulfur compounds – Minimum conversion of feed to lighter products – 10% to 20% conversion • Hydrocracking – Severe type of hydrotreating • Cracking of carbon-carbon bonds • Drastic reduction of molecular weight – 50%+ conversion
- 54. Purpose of Hydrotreating • Desirable for feeds with small concentrations of aromatics & contaminants • Remove contaminants & break aromatic bonds – Sulfur removed as hydrogen sulfide – Metals deposited on catalysts • Breaks aromatic bonds – Lowers average molecular weight – Produces higher yields of fuel products • Minimum cracking • Products suitable for further processing: reforming, catalytic cracking, hydrocracking
- 55. Types • Naphtha hydrotreating – For preparing feedstock to Catalytic Reformer – 230-330 Deg C, 22 kg/cm2g • Distillate Hydrotreating – For clean fuels (Diesel) – 310-390 C, 40 kg/cm2g • Vacuum Gas Oil Hydrotreating – For better FCC feedstock • Residue Hydrotreating – Pretreatment of Coker/VRDS feedstock
- 56. What Does a Hydrocracker Do? • Removes Metals (HDM) 100% • Removes Olefins 100% • Removes Sulfur (HDS) 100% • Removes Nitrogen (HDN) 100% • Saturates Aromatics (HDA) 50-95% • Convert Feed to Products 40-100% • H2 Consumption 1000-2500 SCF/Bbl • Operating Pressure 70-210 Kg/Cm2 • Operating Temperature 315-430°C
- 57. Hydrocracker Process HCU 170-180 Kg/cm2g 380-390 C 350-360 C Vacuum Gas Oil Fuel gas LPG Light Naphtha Heavy Naphtha Kerosene / ATF Unconverted Oil HSD
- 58. Residue Upgradation Process RUP Atmospheric / Vacuum Residue Fuel gas Cracked LPG Naphtha LCGO HCGO Coke / Unconverted Oil
- 59. PRODUCT TREATMENT- OBJECTIVES Primary separation only physical separation; products need treatment to meet desired specifications. To make petroleum products suitable for use with respect to performance, corrosively, suitability of storage, odor etc. Treatment of products to render them marketable – e.g. Hydro-treating of HSD, Merox sweetening of LPG and Gasoline. Recovery of environmentally hazardous materials through processing e.g. Sulfur Recovery Unit. Treatment of intermediate product cuts (e.g. Naphtha, VGO, VR, etc.) before secondary processing (like reforming, cracking) helps to protect catalyst, improve yields.
- 60. Major contaminants of Petroleum distillates and their effects Contaminants Effects Hydrogen Sulfide Acidity, corrosion, obnoxious combustion products, reduced octane no., foul odour Mereaptans Corrosion, obnoxious combustion products, reduced octane no., gum deposits, engine deposits, foul odour Naphthenic Acid Acidity and corrosion Phenol compounds Engine deposits Total Sulfur Corrosion, obnoxious combustion products, reduced octane no. Nitrogen bases Foul odour, colour formation, possible engine deposits Traces of Metals Gum formation, Engine deposits
- 61. PRODUCT TREATMENT • Intermediate & Raw Product Streams from CDU/VDU and Secondary Processing Units like FCC / VBU / DCU are treated to remove impurities to maintain desired Product Specifications. LPG - Caustic Wash / Merox Naphtha – Hydrodesulfurization (NHDS) / Hydrotreater (NHDT) ATF/ Kerosene – Kero Merox (KMU) / Kero Hydrotreater (KHDT) HSD – Hydrodesulfurization (DHDS) / Hydrotreater (DHDT) VGO – Hydrotreater (VGO-HDT) AR – Hydrodesulfurization (ARDS) VR – Hydrodesulfurization (VRDS) FCC Gasoline – Hydrodesulfurization Coker Naphtha & Gas Oil – Hydrotreater Vis-breaker Naphtha & Gas Oil – Hydrotreater
- 62. PRODUCT TREATMENT (Contd.) • Fuel Oil produced from VR, Asphalt produced in SDA & Petroleum Coke from Coker Unit can be utilized for Power Generation. • Petroleum Coke can also be calcined to produce calcined petroleum coke (CPC). Sulphur is a By-product produced in Product Treatment Units De-asphalted Oil (DAO) from SDA - is processed in - Solvent Extraction Unit and - De-waxing Unit, for the removal of aromatics & wax respectively, and Hydrotreated in - Hydro-finishing Unit, for the manufacture of Finished Lube Oil Base Stocks (LOBS).
- 63. PRODUCT BLENDING • OBJECTIVE – To produce marketable finished product of required quality / specifications and suitable for a particular application / end use. • NEED FOR PRODUCT BLENDING – - Availability of multiple streams of same finished product from primary / secondary processing units. - Streams of same finished product needs to be stored together to reduce product tanks requirements. - Finished product optimization with respect to quality giveaway. - Certain intermediate product stream (ex. VR, LDO) doesnot meet finished product specifications.
- 64. PRODUCT BLENDING • TYPES OF BLENDING 1. On-line blending – For products like LPG, Naphtha, MS, ATF, Kerosene, Diesel, etc. 2. Tank to tank blending – For products like Furnace oil, LDO, Lube oil base stocks. * Sometimes ATF and MS are also blended using tank to tank blending.
- 65. LOBS PRODUCTS: 1. NEUTRAL OILS 2. TURBINE OILS 3. INDUSTRIAL OILS 4. AXLE OILS 5. TRANSFORMER OIL 6. BRIGHT STOCK BY-PRODUCT 1. SULPHUR SPECIAL PRODUCTS 1. FG HEXANE 2. MTO 3. INDUSTRIAL SOLVENTS 4. BENZENE 5. TOLUENE 6. MIX XYLENES 7. MTBE 8. LABFS 9. CBFS 10. CALCINED COKE REFINERY PRODUCTS
- 67. CRITERIAS FOR PRODUCT SPECIFICATIONS 1) End Use and Applications 2) Safety in Handling & Storage 3) Environmental Protection 4) Equipment Corrosion 5) Flow Properties
- 68. PRODUCT PROPERTIES • FLASH POINT : Lowest temperature at which vapors from the oil ignite instantaneously. • POUR POINT : Lowest temperature at which no oil flows. • FREEZING POINT : Constant temperature at which oil solidifies. • VISCOSITY : A measure of resistance to flow of oil. • RECOVERY(%) : Percent of oil Distilled at 370 deg. C. • OCTANE NO. : Determines the anti-knock property of Gasoline. Higher the octane, better the anti-knock property. • VISCOSITY INDEX : Determines temperature stability of lube oil with respect to viscosity.
- 69. PRODUCT SPECIFICATIONS Important specifications for main Refinery Products Refinery Product Specification L.P.G. Vapor. Pressure, H2S. Gasoline Octane No., Boiling Range, Sulfur, Aromatic / Olefins content Naphtha Boiling Range, Sulfur Kerosene Smoke point, Flash Pt. Sulfur content Jet Fuel Freezing point, Flash point, Boiling point Diesel Oil Cetane no., Carbon Residue Pour point, Flash Point. Lubricating Oil Viscosity, Viscosity Index,
- 70. TEST - DISTILLATION - Significance varies from Product to Product. - For Crude oil, ASTM Distillation gives idea about the quantum of various fractions. - TBP Distillation reveals characteristics useful for the design of the Refinery. - 10% vol. of Distillation for MS is the indication of ease of Engine start. - Too high FBP will cause crank case oil dilution. PRODUCT QUALITY TESTS & THEIR SIGNIFICANCE
- 71. PRODUCT QUALITY TESTS & THEIR SIGNIFICANCE TEST - VAPOUR PRESSURE - Pressure exerted by vapors when it is in equilibrium with the liquid. - Vapor pressure of volatile, non-viscous products is determined by Reid Method. Significance - Test is important with respect to safety in transport, vapor lock in the gasoline engines, types and design of storage tanks employed. - High vapor pressure entails loss of product during storage and transportation.
- 72. PRODUCT QUALITY TESTS & THEIR SIGNIFICANCE TEST - OCTANE NUMBER - Test for rating the antiknock of motor fuels - O.N. is defined as the % volume of ISO-octane in a Mixture of ISO-octane and n-Heptane that gives the same knocking as the fuel. - Octane requirements of gasoline engines depend on their compression ratio. Significance - O.N. signifies the ignition quality of gasoline in automobile engines.
- 73. - For optimum delivery of power to the engine, fuel-air mixture injected into the engine should ignite at the right time. - Due to heat of compression, the temp. in the cylinder goes high and there could be mistimed ignition. A high octane gasoline is better for ignition. Mistimed ignition produce knocking in the engine. - Knocking in an engine may result in loss of energy and may cause severe damage -Minimum required octane ensures trouble free operation.
- 74. • The different hydrocarbon in gasoline : Straight chains paraffin ISO –paraffin Naphthenes Aromatics ₋ For the same Carbon No; straight chain paraffin have lowest octane No. ₋ Branched chain paraffin (isomers), Naphthenes have higher octane No. ₋ Olefins also have high O.N. but they cause gum deposits in the fuel tank and are not desirable. ₋ Aromatic have high O.N. but their content is being restricted due to their carcinogenic nature.
- 75. PRODUCT QUALITY TESTS & THEIR SIGNIFICANCE TEST - FLASH POINT - Lowest temp. at which application of test flame causes vapor above the sample to ignite. - Flash point below 500C - Abel apparatus - Flash point above 500C - Pensky / Martenes. Significance - Low flash products are potential to fire hazards.
- 76. PRODUCT QUALITY TESTS & THEIR SIGNIFICANCE TEST - CETANE NUMBER - Determined in a single cylinder CFR engine. - Compares ignition delay characteristics of fuel with reference blend of known cetane number. - Reference fuel used are normal Cetane (100 c.n.) and alpha-methyl- naphthalene (0 c.n.). Significance - Indication of ignition quality of fuel - High Cetane number facilitate easy starting of compression ignition engines and lessen engine roughness.
- 77. PRODUCT QUALITY TESTS & THEIR SIGNIFICANCE TEST - SMOKE POINT - Maximum flame height in mm at which fuel will burn without smoking when determined in a smoke point apparatus under specified conditions. Significance - Important test for kerosene evaluating their ability to burn without producing smoke. - Higher the smoke point, better it is for domestic use. - Serves as a guide to assess the aromatic content of kerosene.
- 78. PRODUCT QUALITY TESTS & THEIR SIGNIFICANCE TEST - FREEZING POINT - Temperature at which crystals of hydrocarbons formed on cooling, disappear. Significance - Detection of separated solids in aviation engine fuels at temperatures likely to be encountered during flight.
- 79. PRODUCT QUALITY TESTS & THEIR SIGNIFICANCE TEST - POUR POINT - Lowest temperature at which oil is observed to flow when cooled and examined under prescribed conditions. Significance - Serves as a guide to its pump-ability. - Indicates waxy nature of the oil.
- 80. Gasoline Specification Characteristics Bharat Stage II Euro III Equivalent Euro IV Equivalent Sulfur, % mass, total, max. 0.05 150 (mg/Kg) 50 (mg/Kg) RVP, kPa, max. 35 – 60 60 60 Benzene,% vol., max. 3 1 1 Aromatics, %vol., max. - 42 35 Olefins %, vol., max. - 21 21 Distillation : @ rec. up to 700C,% vol. @ rec. up to 1000C,% vol. @ rec. up to 1800C,% vol. Final BP, 00 C, max. Residue, % vol., max. 10 – 45 40 – 70 90 215 2 10 – 45 40 – 70 75, min. 210 2 10 – 45 40 – 70 75, min. 210 2 RON, min. 88 91 91 MON, min. - 81 81
- 81. Diesel Specifications Characteristics Bharat Stage II Euro III Equivalent Euro IV Equivalent Sulfur, % mass, total, max. 0.05 350 (mg/kg) 50 (mg/kg) Cetane No., min. 48 45 (for Assam crude) 51 48 (for Assam Crude) 51 48 (for Assam Crude) Poly-cyclic Aromatics HC (PAH), % mass, max. - 11 11 Distillation : 95% vol. Recovery @ 0 C, max. 85 min. @ 3500C & 95 min. @ 3700 C 3600 C 3600 C
- 82. Light distillate LPG / C3 Naphtha MS Benzene Toluene Hexane SBP CDU-1 CDU-2 FPU HVU CCU FCCU Crude unit Secondary unit PRODUCTS Vacuum unit Atm residue BH +LS crude Simple Refinery Process Flow Chart CDU-3 VDU HCUImp HS crude Middle distillate MTO Kerosene ATF HSD LOBS LDO Heavy ends Furnace oil LSHS Bitumen Sulfur Train-1 Train-2 Train-3 BH +LS crude HGU1 HGU2 Naphtha DHDS Atm residue VGO VGO BBU NHDS CCR Naphtha ARU LPG C3-C4/MTBE ATU / SRU Acid gas LOBS BLENDING VGO 2.0 mmta 4.0 mmta 6.0 mmta GO GASOLINE SPLITTER Blending streams – 110 To make 32 different grade products Crude & product tanks – >100 CRU