Large Oil Pool Research Articles

Establishment of Aqueous Film Forming Foam extinguishing agent minimum supply intensity model based on experimental method

In recent years, serious fire and explosion accident in petrochemical storage tanks have taken place frequently. Therefore, increasing the firefighting force in petrochemical parks is particularly important. The ambition of the paper is mainly studying the supply intensity of Aqueous Film Forming Foam (AFFF) extinguishing agent. Fire extinguishing agent demand calculation method that can be capable of matching fire scale is established by carrying out series of fire extinguishing experiments. 6% AFFF is chosen to carry out three groups of experiments respectively: fire extinguishing agent fluidity determination, series groups of small size simulation oil pool fire and 177 square meters of large oil pool fire extinguishing experiment. The situation of fire extinguishing on fuel surface of AFFF can be explored through experimental means under cold and hot conditions. The data obtained from experiments prove a higher conformity between covering process and covering model under the cold condition. The model can predict the cold coverage of AFFF effectively. After unifying the supply flow from each experiment, the statistics can be fitted and come to the minimum supply intensity algorithm of AFFF against the target storage tank specifications. The algorithm is used to estimate the minimum supply intensity when extinguishing full liquid surface fire. This model also can be used as reference for petrochemical fire protection.

Predicted new large oil pools in the main petroliferous belt of the Lena-Tunguska province

Almost all the gas-oil and oil-gas fields in the Lena-Tunguska province (Siberian Platform) were discovered in the Baikit, Katanga, and Nepa-Botuobiya petroliferous regions, which form an E-W-striking band. The latter, named “the main petroliferous belt,” includes one giant and 11 large fields (by recoverable oil reserves).New large oil pools are predicted within the main belt. The prediction is based on the analysis of geological data and the quantitative estimation of hydrocarbon resources. Promising areas with large fields in the Baikit, Katanga, and Nepa-Botuobiya petroleum regions are substantiated.

Characteristics of large cooking oil pool fires and their extinguishment by water mist

Large cooking oil pool fires, occurring in industrial oil cookers, present a severe hazard to food processing plants due to their size and the large amount of hot oil involved. This paper reports a series of full-scale fire experiments conducted in a large industrial oil cooker mock-up. The characteristics of large cooking oil pool fires and the effect of oil depth and hood position in the oil cooker on fire growth were studied. The use of water mist for extinguishing large oil pool fires and their extinguishing performance under different discharge pressure and with different types of water mist systems were investigated. Experimental results showed that the cooking oil underwent a substantial expansion in volume during heating. The fires developed quickly once the oil auto-ignited. The fire growth rate was affected by the oil depth in the pan and the hood position in the oil cooker. The water mist fire suppression systems effectively extinguished large cooking oil fires and prevented them from re-igniting. Their extinguishing performance was determined by the type of water mist system, discharge pressure and hood position in the oil cooker.

Application Of Water Mist To Extinguish Large Oil Pool Fires For Industrial Oil Cooker Protection

Large oil fires occurring in industrial oil cookers are very challenging to extinguish due to their size and the large amount of hot oil involved. This paper reports a study to use water mist for large industrial oil cooker protection. The extinguishing mechanisms of water mist and corresponding criteria required for extinguishing large pool cooking oil fires were investigated both theoretically and experimentally. Based on the extinguishing mechanisms and required criteria, two water mist systems were developed in the present work. A series of full-scale fire tests were conducted in a large industrial oil cooker mock-up. The study showed that the two water mist systems presently developed worked effectively to extinguish large cooking oil fires and prevented them from re-igniting. Their extinguishing performance was determined by the type of water mist system, discharge pressure and hood position in the oil cooker.

Geochemical Analysis of Reservoir Continuity and Connectivity, Arab-D and Hanifa Reservoirs, Abqaiq Field, Saudi Arabia: ABSTRACT

Organic geochemistry and its integration with geologic and reservoir engineering data is becoming increasingly utilized to assist geologists and petroleum engineers in solving production related problems. In Abqaiq Field of eastern Saudi Arabia, gas chromatographic analysis (FSCOT) of produced oils from the Arab-D and Hanifa reservoirs was used to evaluate vertical and lateral continuity within and between these reservoirs. Bulk and molecular properties of produced Arab-D oils do not vary significantly over the 70 km length and 10 km width of the reservoir. Hanifa oils, however, do reflect two compositionally distinct populations that are hot in lateral communication, compatible with the occurrence of a large oil pool in the southern part of the field, and a separate, and smaller northern accumulation. The Arab-D and underlying Hanifa oil pools are separated by over 450 feet of impermeable carbonates of the Jubaila Formation, yet the Southern Hanifa pool and the Arab-D have been in pressure communication since onset of Hanifa production in 1954. Recent borehole imaging and core data from horizontal Hanifa wells confirmed the long suspected occurrence of fractures responsible for fluid transmissibility within the porous (up to 35%) but tight (<10md matrix K) Hanifa reservoir, and between the Hanifa andmore » Arab-D. The nearly identical hydrocarbon composition of oils from the Arab-D and southern Hanifa pool provided the final confirmation of fluid communication between the two reservoirs, and extension of a Hanifa fracture-fault network via the Jubaila Formation. This work lead to acquisition of 3-D seismic to image and map the fracture-fault system. The molecular fingerprinting approach demonstrated that produced oils can be used to evaluate vertical and lateral reservoir continuity, and at Abqaiq Field confirmed, in part, the need to produce the Hanifa reservoir via horizontal wells to arrest the reservoir communication that occurs with existing vertical wells.« less

Evaluation of CO2 Flood Performance: North Coles Levee CO2 Pilot, Kern County, California

Summary CO2 injection began on June 1, 1981, in the Main Western (MW) III interval of the North Coles Levee field Kern County CA, to test the tertiary potential of the reservoir to CO2. The pilot test was designed to inject continuously a 40 %-HCPV slug of CO2 into two inverted 5-acre [2.02-ha] 5-spot patterns and one 10-acre [4.05-ha] linedrive pattern. The injection was switched to water near the end of CO2 injection because of the CO2 source loss. Overall pilot test performance varied; oil production increased above secondary decline in some wells, but not in others. A simulation study was initiated to determine the dominant mechanisms controlling pilot performance. The simulation study investigated the influence of reservoir description, gravity override, communication with other producing horizons. and production strategy. Simulation results indicate that a random permeability description with Zone MWIII in communication with upper zones is most appropriate. Gravity override of CO2 into the upper zones dominated displacement efficiency. These results indicate that dual injection of CO2 low in MWIII and of water high in MWIII would greatly enhance sweep efficiency. Further analyses with oil and CO2 production data from individual wells and a post-CO2 tracer test showed that the test was a technical success in wells that responded to CO2 and that grouping and analyzing all pilot wells together masks the true incremental oil response to CO2. This is true mainly because some wells that never responded to CO2 experienced well problems that severely curtailed their production and that offset increased production from wells that did respond to CO2. The pilot test patterns are badly out of balance, possibly because of operational patterns are badly out of balance, possibly because of operational imbalance, directional permeability or a combination of the two. Introduction EOR by CO2 injection in watered-out reservoirs has been proven in several reservoirs throughout the world. This paper documents an analysis of the first application of CO2 injection in the Kern River Valley, Kern County. CA. Although California is well known for EOR by application of thermal methods to viscous oil reservoirs, it also has many deep, light-oil reservoirs discovered in the 1930's and 1940's that are approaching their economic limits from waterflooding. The North Coles Levee field is typical. A pilot study was initiated to test the potential of CO2 in three patterns on field spacing. Many problems have plagued the project, especially mechanical problems in wells that did not respond to CO2. The primary purpose of this study is to determine the technical success of the pilot test and to identify the dominant mechanisms controlling the process. The pilot test was analyzed by attempting to identify mechanisms that could account for the response to CO2 injection by use of reservoir simulation and a detailed well-by-well analysis of actual field production, injection, and tracer data. The lack of data-especially fluid saturations, pressure distribution, and a pilot-wide reservoir description-hinder a detailed simulation, but controlling processes can be qualitatively derived. Field and Pilot History The North Coles Levee reservoir is a large oil pool located in the Stevens sand interval about 10 miles [16.1 km] west of Bakersfield, CA, in the Kern River Valley (Fig. 1). Table 1 summarizes reservoir properties. The reservoir is mature and approaching its economic properties. The reservoir is mature and approaching its economic limit from waterflooding. The field was discovered in Nov. 1938 and produced by gas-cap expansion until Nov. 1942, when fluid withdrawal produced by gas-cap expansion until Nov. 1942, when fluid withdrawal was balanced by gas injection to preserve reservoir pressure. This included injection of make-up gas and gas cycling. A controlled blowdown of gas was started in 1965 because the economics favored gas sales over continued gas injection, allowing reservoir pressure to drop below 1,000 psi [6895 kPa]. A pilot alternating propane with water and dry chase gas was tried in 1964, but was unsuccessful because of early breakthrough and a diminishing supply of propane. A waterflood pilot was started in 1967. A fieldwide waterflood was started in 1970 pilot was started in 1967. A fieldwide waterflood was started in 1970 and continues to the present. Water preferentially enters the gas-swept region, while fluid withdrawals come mainly from the lower regions of the reservoir. This has led to a higher pressure, greater than 5,000 psi [34 475 kPa], in Zone MWI compared with 4,500 psi [31 027 kPa] in Zones MWII and -III. Because of underbalanced withdrawals in Zone MWIII, the waterflood was infill-drilled at 20- and 10-acre [8.09- and 4.05-ha] spacing (Fig. 2). Some patterns were converted to linedrive or irregular configurations later in the waterflood. Rod pumps were used for artificial lift on most producing wells. Gas lift was used on the remaining wells.

Geochemical Relationship Between Petroleum and Coal: ABSTRACT

Large oil pools and coal beds are occasionally found associated within the same sedimentary series, but mostly in tertiary basins. For some of these series it has been demonstrated that the oil originated, at least partly, in the coal beds. This is probably true for more of them, although it was not demonstrated, given the lack of geochemical studies. In Paleozoic series, which account for most coals, at least in Europe, association of oil pools and coal beds is very rare. Moreover the oil pools are small. However, gas pools originating in coal beds have been found, and some are very large. Pyrolysis studies indicate that most coals, whatever their ages, have a variable but often fair capacity to produce oil in geologic situations. However, for Paleozoic coals, as for many other Paleozoic kerogen bearing sediments, complex geologic history resulted in migration dissipating the generated oil. In some favorable situations, reburial in post-Paleozoic times produced gas, and the presence of very efficient seals (salt) allowed gas pools to form. Furthermore, petrographic examination shows the exinite content should not be taken as a measure of oil potential, because a large part of this potential lies in macerals which are classified presently in the vitrinite group. Careful use of the methods of petroleum geochemistry will increase the chances of finding oil pools in Paleozoic coal measures of Europe. End_of_Article - Last_Page 794------------

Primary migration theory of petroleum and its application to petroleum exploration

Current concepts of oil and gas generation by thermal decomposition of kerogen are reviewed. Primary oil migration mechanisms requiring large quantities of water to serve as a carrier for the movement of oil from source rock to reservoir are discussed. Previous investigators regarded the expulsion of interlayer water from montmorillonite and montmorillonite-illite mixed-layer minerals by transformation during diagenesis as the most important source of the carrier water. The process of diagenesis is subdivided into three stages based on the results of experimental compaction studies on montmorillonite clay, on studies of the expulsion mechanism of interlayer and interstitial waters, and on the observed changes in pores and mineral grains in argillaceous sediments during these stages. As a result, we concluded that the migration of oil chiefly occurs during the late compaction stage when the sediment's porosity ranges from 30 to 10%. This conclusion implies that a large amount of oil can move during the period when the active generation of oil corresponds with the primary migration of carrier water. For instance, in the oil-bearing Miocene sediments of the Akita area of northern Japan, the oil generation temperature ranged from 100 to 150°C and the average migration depth was between 1300 and 2600 m. Therefore, the possibility of large oil pool formation will be high in the basin where the paleo-geothermal gradient is about 5.0°C/100 m. In fact, it is expected that the paleo-geothermal gradients in the vicinities of large oil fields will be very close to this value. Prediction of the type and amount of hydrocarbons in the exploration area will be possible by an examination of the paleo-geothermal gradient in the area and by a study of the relation between absolute porosity and burial depth of argillaceous rocks.

Forties Field, North Sea

The Forties field, a large oil pool discovered in 1970, is in the northern part of the British sector of the North Sea, 175 km (110 mi) east of Peterhead, Scotland, in water depths of 91 to 131 m (300-430 ft). The reservoir is a sandstone of Paleocene age at a depth of about 2,135 m (7,000 ft), at the base of a thick Cenozoic section consisting primarily of mudstone. The Paleocene sandstone/mudstone sequence is underlain by Danian and Maestrichtian chalk. The trap is a broad low-relief anticlinal feature with a closed area of 90 sq km (35 sq mi). Maximum gross oil column is 155 m (509 ft). Recoverable oil is estimated at 1.8 billion bbl from an in-place figure of 4.4 billion.

CLIMATE AND OIL GENESIS

Studies of the Caspian Sea, the Barents Sea and others, show that the rate of accumulation of organic matter in sediments and the nature of its initial change is largely dependent on climate. All known large oil pools are located in basins which had a warm environment at the time of deposition. Occurrences of gas in colder zones were associated with coal rather than oil. Exploration for. oil in polar areas should be restricted to rocks known to have been deposited in warm paleoclimatic conditions. All evidence denies the inorganic theories for the origin of oil. — M. Russell

Sulphur Isotope Abundances in Petroleum and Associated Materials

A study has been made of the sulphur isotope ratios for petroleum from many different oil fields in the United States and Canada. The S34/S32 ratio for petroleum varies by about 4.5 per cent as compared with a total spread of about 9 per cent for terrestrial sulphur. The single large oil pools appear to be uniform in isotopic content. Also, oils from widely separated locations in Alberta, found in the same reservoir rock, have similar sulphur isotope ratios. On the other hand, the actual sulphur content of these latter oils may vary by a factor of 10. This result indicates that there is little or no fractionation of the sulphur isotopes in the maturation of the oil in which sulphur is lost. The fact that the H2S and its associated petroleu have similar sulphur isotope content is further evidence for this view. The sulphur isotope ratio for petroleum would seem, therefore, to give information concerning the isotopic content of the source sulphur at the time of petroleum formation. This in turn would reveal something about the environment in which the petroleum was formed. The very high S34 content of the petroleum in the recent sediments of the Uinta basin in Utah confirms the non-marine origin of these deposits. The decrease in S34 content with age and depth of petroleum deposit in the basin suggests a gradual S34 enrichment of the sulphate over a period of time in the enclosed lake, probably due to bacterial action.