Types of Crude Oil

The above description of hydrocarbons refers to simpler members of each family, but crude oils are actually complex mixtures of very long-chain compounds, some of which have not yet been identified. Because such complex mixtures cannot be readily identified by chemical composition, refiners customarily characterize crude oils by the type of hydrocarbon compound that is most prevalent in them: paraffins, naphthenes, and aromatics. Some crude oils, such as those in the original Pennsylvanian oil fields, consist mainly of paraffins. Others, such as the heavy Mexican and Venezuelan crudes, are predominantly naphthenic and are rich in bitumen (a high-boiling semisolid material frequently made into asphalt for road surfaces).

Given the pattern of modern demand (which tends to be highest for transportation fuels such as gasoline), the market price of a crude oil generally rises with increasing yields of light products. It is possible to process heavier crudes more intensely in order to improve their yield of light products, but the capital and operating costs required to support such high conversion processes are much greater than those required to process lighter crudes into the same yield of products.

In addition to the hydrocarbons, compounds of sulfur, nitrogen, and oxygen are present in small amounts in crude oils. Also there are usually traces of vanadium, nickel, chlorine, sodium, and arsenic. These elements may affect the safety of oil-transport systems, the quality of refined products, and the effectiveness of processing units within a refinery. Minute traces can usually be tolerated, but crudes with larger amounts of these materials must be extensively treated in order to restrict their harmful effects.

Crude oils vary greatly in their chemical composition. Because they consist of mixtures of thousands of hydrocarbon compounds, their physical properties such as colour, specific gravity, and viscosity also vary widely.

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The Kumkol oil field was discovered at the beginning of 1984. Development commenced in 1990 and the first oil gusher confirmed that the Yuzhno – Turgou depression, where Kumkol is located, had large reserves.

The climate is noted for wide daily and seasonal fluctuations in temperature. In summer the temperature can reach up to +35°C while in winter months it may drop to - 40°C. Winds never subside and the snowstorms are violent. Problems with water supply in this remote are a make the work more difficult. Working conditions are very hard, but it is a rewarding experience.

In 1993 year we produced 1.800.000 tons of oil while this year the production volume is expected to increase by 150.000 tons. Our design capacity is 3.100.000 tons of oil annually and is targeted to be reached in 1997. Since the beginning of the development of Kumkol, the total volume of production has reached over 5 million tons of oil.

Over this period we drilled 210 wells, of which 117 are now in operation, while construction of oil field facilities is in progress for another 86 wells. In addition, much was done to improve the living and working conditions of employees.

New market relations and privatization were the reasons behind the establishment in may 1994 of the joint stock company Yuzhneftegaz in which the government has a controlling stake. It consists of 13 branches employing about 4.000 people. All of there are on – site service personnel.

Currently, a remodeling project is being implemented which focuses on production facilities and the utilization and processing of oil and gas. Plans are also afoot to purchase state of the art drilling equipment and equipment for processing associated gas. In the areas bordering on Kumkol we have discovered over 10 new prospective fields and have attracted foreign firms to develop them. As a cofounder of two joint ventures, Turan Petroleum (with Canada) and Germunai (with Germany), Yuzhneftegaz has a 50% stake in each. We are prepared to expand cooperation with foreign firms and are ready to consider any proposals for partnership.

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