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Module 1: Prodotti petroliferi

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    Hi friends now we will discuss on the topic petroleum as a source of energy. In the previousclasses we have seen that after coal the petroleum is mostly used as energy resource around theworld and this is also a fossil fuel. And now we will see what is petroleum? What isthe composition of it and what is the heating value of it and what are the different formsof energy we can get from it and what are the issues, types of it etcetera.So, now the contents are here, what is petroleum? Origin of petroleum, availability of petroleumand energy production from it, types or grades of petroleum and petroleum products, its characterization,its classification and energy content, composition of crude oil, pricing of petroleum and petroleumfor energy production: some issues. These are the contents of today's discussion.Now let us see what is petroleum? so as the word says petroleum it is derived from thePetra and oleum so Petra means rock and oleum is oil. So, literally it means that rock oiland it is defined as a, it is basically a mix of naturally occurring organic compoundsfrom within the earth that contain primarily hydrogen, carbon and oxygen. So, petroleumand crude oil these two terms are used widely and apparently both are similar and are usedfor the same purpose.Where the crude oil is a complex mixture of hydrocarbons, different types of hydrocarbonsparaffin’s, naphthenes and aromatics and brownish black in colour and colloidal innature petroleum is also similar, same. The only difference is that petroleum is a broadcategory that includes both crude oil as well as the petroleum products. And if we see theelemental composition of these it contains carbon, hydrogen, nitrogen, oxygen, sulphurand metals.So, mostly carbon then hydrogen but here hydrogen is more with respect to coal and heating valueis also higher in case of this. Now we will see the origin of petroleum, how the petroleumwas originated? In case of coal we have seen that there are different thoughts who explainthe formation of coal under the earth crust. Here also there are different thoughts, heresome thoughts says that it is originated from animal sources and some thoughts says thatit is from inorganic sources.So, one is inorganic and organic theory, unlike coal this is suppose that petroleum is originatedfrom animal sources but coal was from plant sources that is what this organic theory.Now if we see the inorganic theory then this theory says that carbon and hydrogen cametogether under high pressure and temperature below the earth's surface and formed oil andgas where chemical reactions took place.Organic theory says that the most that the substantial conditions for the formation ofpetroleum such as saturated soil, absence of oxygen and high pressure and temperatureconditions, under these condition the decay of organic matters transformed into kerogenforming source rock. So, that is the source of the petroleum and it is assumed that theanimal bodies are converted to this petroleum.Now what is the availability of petroleum and energy production from it? If we see thetotal world oil reserves then we get conventional oil 30%, heavy oil 15%, extra heavy 25%, andoil sand is 30%, so these are the different parts or the type of petroleum resources.And worldwide reserve by region wise if you see middle-east have around 49%, then America,North America 13% and Central and South America 20% then Africa is only 8% and Eurasia is7% but we Asia has very less reserve. We also have some reserve but very limited.Now if we see the world energy used by fuel then Asia Pacific region North America, Europe,Russia, Middle East, South Central America and Africa we see here now while oil is usedeverywhere in significant amount after coal. And the prediction says that we are here atsay somewhere see prediction says that the world liquid oil and gas depletion has predictedin 2004 that in future the amount will be reduced, the availability of this oil maybe reduced in near future.Now we will see the types and grades of petroleum. So, petroleum can be divided into differentgrades depending upon the degree API that is a specific gravity. So, light crude, heavycrude and medium crude oil. So, light crude means its degree API is higher more than 31.1API and heavy is dense oil so it is having API below 22.3. So, in between these two 22.3to 31.1 this is called medium oil. So, this is one way of classifications of the oil thatis light, medium and heavy oil.So, if we see the availability of the oil petroleum crude around the world we can getthree major locations the one is your West Texas Intermediate in America another is yourBrent blend, it is also located in the North Sea and then OPEC reference basket that isin Algeria, Iraq with Libya Qatar, Iran, Saudi Arabia, Indonesia, Nigeria, Venezuela andUAE. If we say this crude oil it's relatively of lower quality degree API is 32.7 whereashere we will get the highest quality 39.6 degree API and sulphur is also 0.24%.And this is medium that a 38.3 lesser than 39.6 and sulphur is also higher than this0.37% and here the sulphur is higher and this API gravity is also lower. So, in terms ofthese three this is of inferior quality crude oil.Now what we will see different crude oil will give us different yield. So, you see someexample Bombay High, Bonny light and Arab light and Kuwait. So, these different sourcescrude oil if we take and if we want to refine it, we will not get the similar type of products.In India you see the Bombay High crude we are having very high amount of middle andlight distillates also but heavy ends are also relatively less in this case.So, the quality of the oil available in India in Bombay high it is good but Reserve is lessbut here you see Kuwait the heavy end is very higher amount then middle distillate and thenlight distillates. So, the origin of the petroleum will also can generate or can give differenttype of liquids after its refining or we need different types of technology to process thisdifferent type of feedstocks to get certain amount of liquid product.So, this slide gives us some comparison of middle-east crude quality that is Arab mix,Iran light Iran heavy and Kuwait and Bombay High so these are the properties like saygravity, pour point, wax content, asphaltenes, total sulphur and yields, light distillates,middle distillates, residue it is given. So, one thing it is clear that here it is havingless residue higher the API lesser the residue obviously because it is lighter.So, residual part will be less then what are the difference liquids we can get or differentenergy we can get from this, different form of liquids which can be used for energy sourcefrom the petroleum crude that we want to discuss. Now so crude will be refined first and differentfractions we will get.So, here we are getting the crude it is heated, pretreated that is fractionated in this column,after fractionations we get different products as shown here C1 to C4 gases will get LPGhere 220 degree centigrade and then here say C5 to C9 naphtha we will get 70 degree centigradeand C5 to C10 petrol or gasoline we can get at 120 degree centigrade C10 to C16 we canget kerosene and at 170 degree centigrade.And C4 to C20 we can get diesel oil that is equal 270 degree centigrade and C22 to C50that is lubricating oil and then C22 to C70 fuel oil and then the residual. So, theseare the different fractions we can get from the crude oil and those fractions can be usedin different applications like say LPG as a heat source and then naphtha is very, veryimportant. Once naphtha can be converted to different types of chemicals that petrochemicalsso we can get Petro chemicals from naphtha and as you know that diesel, petrol all thosethings are used to run vehicles.And ATF aviation turbine fuel is also used that is the jet fuel there is a kerosene andATF are having very similar properties and others are fuels that is lubricating oil isalso used for the lubrications of machines. And residual part this is one issue that thatcan create a lot of pollution and we have a scope to improve the quality of residueso that we can reduce the loss and we can improve the economy of the process also.So, now we will see the different refined products so gasoline, diesel and jet fuelthese are the major products which are produced through the refining of petroleum crude andused in different types of transport. And other secondary products are kerosene, LPG,fuel oil, asphalt, carbon black oil, lubricating oil, waxes, petroleum coke and those thingsand sulphur if you can recover then that can be used for chemical synthesis.And NaHS that is used can be paper, copper mining and leather industries. So, these arethe different refined products which you can get from petroleum refinery and that can beused for different applications. So, one way it is giving us energy other way it is alsogiving us different types of petrochemicals. Now we see the heating value of the differentproducts which we can get from the petroleum crude refining.So, LPG, gasoline, kerosene, diesel and residue, heating value is this much for a LPG 46.1mega Joule per kg then gasoline 46.5 mega Joule per kg, kerosene 46.2 mega Joule perkg, diesel 45.8 mega Joule per kg and residue 42.2 mega Joule per kg but in this case whatwe have discussed in the previous slide also that there is a specific temperature it ismentioned but we have some flexibility to vary this temperature and to maintain theor the control the quality of the products also.Then different petroleum products which we get that we have different boiling pointswe have discussed and that boiling point largely determines the size of the molecules and whattype of product will get more. And overlap in boiling ranges provides flexibility inproducts and just we have discussed when you see LPG, gasoline, kerosene, diesel, lightgas oil, heavy gas oil and the residual. So, this is the temperature at which we can get,these are the temperature we can get different types of product.Now we will see what are the compositions of a petroleum crude or petroleum? So, petroleumcrude oil if we see that is hydrocarbons basically. So, it will be mostly hydrocarbons and nonhydrocarbons are also present those are called impurities. So, hydrocarbons may be aliphaticnaphthenic, naphthenes and aromatics so these three types of hydrocarbons basically presentin crude oil and non hydrocarbons are like sulphurs, nitrogens, oxygens and metallicsthey are basically present in it.And typical range is given say 25% asphaltic, 17% aromatics, 50% naphthenes and naphthenesis very important it is used for the production of different types of chemicals naphtha. Andthen sulphur is this one nitrogen is less and oxygen is also less and metals is alsovery less, less than 100 ppm. And these are the molecular structure of these differenttypes of compounds which is present in it or hydrocarbons present in it.This is aromatic ring it has and it has some naphthenic rings, naphthenes. So, aliphaticand the paraffin are basically present in the crude oil and then isoparaffinic compoundsare also present in largely in large amount. So, isoparaffinic and paraffinic both arepresent in asphaltic.Now we will see some example of this isoparaffin’s that is propane, n-butane, n-hexane, n-heptane,n-octane, n-nonane, n-decane, n-undecane, n-dodecane, n-tridecane, so this is C2 toC13 some boiling range are given here. So, obviously the higher the carbon number morewith the boiling range. So, upto C3, C4 basically we get it in LPG.Now the paraffin’s which are available in petroleum crude basically they are havingsay CnH2n +2 formula, CnH2n+2 and the compounds which are higher carbon, whichare having higher carbon that is say C16H34 they are mostly in solid form and in somecases we get mostly we get C40H82 and in some cases we can get C100 even mostly up to C80we get, in some cases we can get more than that that is C100.And these paraffin’s are low in heavy graded oils that is up to 35% in light Crudes andSulphonated this paraffin’s can be used for biodegradable detergent production andoxidation of C8 and C30 N-paraffin’s results fatty acids and soap industries and oxidationof C12 to C14 normal paraffin’s results secondary alcohols. And this paraffin waxwhich is available higher carbon number of paraffin’s, they contribute on freezingpoint of ATF, Aviation Turbine Fuel. Cold flow properties of diesel and lubes and ignitionquality of gasoline and diesel.And isoparaffin’s which are available in this the general formula is CnH2n+2 and C4to C33 have been isolated in petroleum in higher extent and predominant form is herethe CH3, CH3 chain as a side chain is available in most of the cases and highest concentrationof two methyl alkanes in C6 to C8 range it is available and di and tri substituted areless abundant and are mainly present in higher boiling fraction.And most desirable components for the gasoline this one this isoparaffin’s are desirablefor gasoline, ATF and lubricating oil and these are the; if we have highly branchedisomers then this is not undesirable.The naphthene is CnH2n+2-2RN say this is one naphtheneso how many this is C C C C C C C C so how many moles num 1 2 3 4 5 6 7 8. So, 8 n equalto 8 so H we are having 2 H 2 H 2 H 2 H and then 2 H again here we will have 2 H and 2H and here 1 H and 1 H, so these 2RN, RN means 1 and 2, 1 and 2 we have 2 rings 2 rings soRN is the number of naphthenic ring in this case if this one, we have one ring so RN equalto 1 so this is the general formula.So here in this case n equal to 8 so that will be 8 + C 8 H 2 into 8 + 2 - 2 into 2.So, this is the formula of this naphthenic compound. Now in crude oil naphthenics arepresent about 50% by weight and its quantity is higher in heavier fractions, higher theheavier the crude more the naphthenic compounds. And if naphthenes are present then what willhappen? They will give us more naphtha and lubricating oil and these are stable hydrocarbonand cyclopentane, cyclohexane and their alkylated derivatives are normally found.In aromatic hydrocarbons aromatic hydrocarbons means some benzene ring will be availableor more number of rings may be available in this case. So, general formula is CnH2n-6or C2nH2n-12 so this is the formula and these are already 15% of weight in crude oil itis and more the this aromatic present in it so what will be happen in this case octanenumber will be boosted. So, for gasoline it will be preferable so the octane number ofaromatic hydrocarbon is much higher than the paraffins and Isoparaffins and these are chemicallyreactive and can form both addition or substitution products and high amounts of polycyclic aromaticare present in heavy gas oil lubricating oil and in residues.Now we will see main constituents of crude oil so basically carbon and hydrogen thisis the main constituent and different fractions of this LPG, gasoline, gas oil, VGO and residueif we see basically the LPG paraffins then gasoline, paraffins, aromatics and naphtheneskerosene also same and the residue is mostly asphaltic and their carbon range is givenhere. These are the typical range.Now how we will price the crude? How the crude oil is priced? What is the cost is decidedon which basis? Obviously it will be on its quality and degree API and sulphur contentboth are considered for its pricing. In case of coal we have discussed that ash contentand moisture content was also considered. So, in this case we have our sulphur and APIthey are used to fix the price. And then high sulphur heavy crude is obviously in low cost.If you see we increase these if you go that way so degree API is increasing the qualityis improved the light it is becoming lighter and lighter. And then sulphur content so sulphurcontent is also reducing so cost is higher, higher cost low sulphur and high API thisis the basis the price is fixed.But how the price will be fixed? There are benchmarks some benchmark one benchmark isyour West Texas Intermediate, WTI, and then this is also called as Texas light sweet anotheris Brent crude and another is OPEC reference basket. So, in India we mostly dependent onOPEC reference basket and the price is dependent on many factors what would be the crude pricetoday tomorrow it may change. So, that will be influenced by many factors those are supplyand demand fundamentals.Then we have OPEC policies, the organization's of the Petroleum Exporting Countries theyhave the members of this Iran, Iraq, Kuwait, Saudi Arabia etc so this country they havetheir policy and political issues also influence it. The political and economic developmentsin the exporting and consuming countries, so what is the relationship between Indiaand Iran or Iraq or Kuwait so that will also influence the price of the crude. And weatherconditions because how it will be transported and what is the weather conditions that willalso influence our crude price.Then Petroleum for energy production: Some issues, we will be discussing some issuesnow. So, oil based economy and carbon credit that is one issue. You know we, our societyis mostly dependent on oil utilization and it produces carbon dioxide. So, if we usemore oil so we will be producing more carbon dioxide so carbon credit will be in considerationso that is one issue so you have to optimize the things that carbon emission will be reduced.And depletion of high-quality crude oil, the high-quality crude oil is being reduced asyou have seen in a one slide that it is projected that the supply of crude oil will be reducedand even the quality is also degraded day by day. So, lower the quality more the SOxemission and more the ash emission, so industrial emissions will be more with the degradationof the quality of the crude oil. And a sustainability issue, in 21st century sustainability is anissue where we have to ensure the energy supply, we have to environmental quality and socialequity.So, under these situation if we see the carbon emissions from liquid fuels so here we havemillion tons CO2 released so total this much so year 2020 say 36834 million tons of CO2is expected to come from different types of fuels and liquid fuel from it is expectedto come 13582 million tons of CO2. So, around one third of the total CO2 is coming fromthe liquid fuel so this is one concern that how to control the carbon dioxide emissionfrom these fuel if we want to use more effectively this feedstocks for energy resource.And then another target is that as per Kyoto protocol we have to reduce the carbon dioxideemission level in 1997 which we had and now 2010 we had some target that 10% will be reduced,the carbon dioxide emission will be reduced and 2020 it is targeted to reduce by 20% sowe are under pressure we have to reduce the carbon dioxide emission from all source ofenergy and other activities.And this liquid fuel contributes on carbon dioxide emission so we have to take actionswe have to develop cleaner technologies for its proper applications. So, upto this inthis class thank you very much for your patience.