The petroleum industry has evolved over the years to become a gigantic industry. Personnel in the areas of sciences & applied sciences are required:• Petroleum engineers• Mechanical engineers• Chemical engineers• Electrical engineers• Computer scientists• Physicists• Chemists• Marine biologists &• Geologists engineers• Others There2 broad classifications of globalpetroleum industry:• National Oil Companies (NOC)• International Oil Companies (IOC) Very large in terms of production, & some substantial in refining. They are owned by their respective governments. They account for about 33.33% of world crudeproduction. Examplesof NOCs:• Petronas (Malaysia)• Petroleos de Venezuela – PDVSA (Venezuela)• Saudi Aramco (Saudi Arabia)• Statoil Hydro (Norway)• Petrobras (Brazil)• PEMEX (Mexico)• NNPC (Nigeria)• Sinopec, CNOOC (China)• GNPC (Ghana) Also known as Multinationals. They have a significant proportion of their operations in several different countries. There are 5 major IOCs:• British Petroleum (BP)• ChevronTexaco• ExxonMobil• Royal Dutch/Shell (simply Shell)• TotalFinaElf (simply Total) Strength of the “Big Five”:• Production in more than 15 countries.• Refining in more than 15 countries.• Products marketing in more than 40 countries.• They account for approx. 13% of world production.• They account for 21% world refining.• They account for 35% world product sales. OtherIOCs are:• Amerada Hess• Anadarko• ConocoPhillips (simply Phillips)• ENI/Agip• Kerr McGee• Occidental• Repsol• Unocal The 2 main sectors in the industry are: Upstream Sector• Producing• Servicing DownstreamSector• Refining• Products sales• Transportation Basically involves the extraction & field treatment of oil & gas. There are 2 divisions:• Research & Development (R&D)• Exploration & Production (E&P) Research& Development (R&D)• Scientific inquiry to discover facts, new or better methodology & technology. Exploration& Production (E&P)• Field operations where petroleum deposits are being searched for and then produced. In the Upstream sector, there are 2 types of industry:• Producing Companies• Servicing Companies “Officially” recognized to be directly involved in petroleum exploitation. They are given permissions by the host country to operate within a carved out areas called Blocks. Examples: ExxonMobil, Chevron, NPDC, Petrobras, Statoil, Saudi Aramco, Royal Dutch Shell, Total, etc. “Officially” recognized to be indirectly involved in petroleum exploitation. They provide sales & services to producing companies in terms of personnel, research, technology, field operations, and tools & equipment. Examples: Transocean, Halliburton, Pride International, Schlumberger, BJ Services, Weatherford, Baker Hughes, etc. It involves refining, transportation, storage & marketing of petroleum products. After the initial field treatment of petroleum (separation of gas, oil & water), it is transported to the refinery by truck, train, ship, or pipeline. The basic refining tool is Distillation. Thermal cracking is used to increase the yield from distillation by subjecting the heavy crude oil to intense heat. Alkylation involves recombination of small molecules produced by thermal cracking in the presence of a catalyst. Catalytic cracking involves crude oil being cracked in the presence of a finely divided catalyst.