Crude Oil Storage Tanks Research Articles

06/01102 Characterization of paraffinic deposits in crude oil storage tanks using high temperature gas chromatography: Boukadi, A. et al. Applied Geochemistry, 2005, 20, (10), 1974–1983

06/01102 Characterization of paraffinic deposits in crude oil storage tanks using high temperature gas chromatography: Boukadi, A. et al. Applied Geochemistry, 2005, 20, (10), 1974–1983

Characterization of paraffinic deposits in crude oil storage tanks using high temperature gas chromatography

Problems related to the crystallization and deposition of heavy organic fractions during production, transportation and storage of crude oils can lead to considerable financial losses for the petroleum industry. The heavy organic fractions may include paraffins or waxes, resins, asphaltenes, and organometallic compounds that exist in crude oils in various quantities, states, and forms. The severity of the deposition problems varies widely and depends on factors such as the crude oil composition, operating conditions in the reservoir and production procedures. Problems associated with the solid deposits may be encountered anywhere in the production process from the reservoir to the refinery. In this paper, it is proposed to focus on production problems associated with certain fields in Tunisia. The problems manifested themselves through the accumulation of solid deposits in the storage tanks at a Tunisian terminal and originated from the mixtures of various crude oils transported to the terminal by pipeline. The principal analytical method for the characterization of the solids was high temperature gas chromatography following concentration of the wax fraction through a modification of the conventional acetone precipitation technique.

Cathodic Protection System for Crude Oil Storage Tanks and Water Pipelines in the Refinery

The aim of this paper is to investigate the cathodic protection system (CPS) in Al-Zawia refinery company (ARC). There are two problems for a cathodic protection system: the first one is the overprotection where the potentials exceed −2.0 volts versus Copper/Copper sulfate reference electrode for some areas on firewater pipeline, which are near groundbeds. The second problem is under protection in the area where potential as low as ( − 0.7 volts) along the sea berth pipeline. Several solutions were suggested for these problems, such as: burying the scrap between the line and the ground, decreasing the conductivity of soil, areas of overprotection points should be cleared up and connected to an external connection, and removing the scrap near the sea berth pipeline.

The effect of impellers layout on mixing time in a large-scale crude oil storage tank

This paper reports the results of a study on the effect of the position of impellers on homogenization time in a large scale 19,000 m 3 crude oil storage tank. Based on the good agreement found between the predicted and the site measured results for an existing tank equipped by a single impeller, the hydrodynamics of the flow generated by two, three and five side entry impellers arranged in two different orientations is theoretically studied. In order to achieve this, an in-house CFD code with the ability of simultaneous solving of continuity and Reynolds-averaged Navier–Stokes (RANS) equations is used. The RNG (renormalization group) version of the k- ε turbulence model is applied for turbulence modeling. The fluid region is divided into a large number of control volumes (580,000 to 900,000), and the MFR (multiple frames of reference) model is used for impeller modeling. The velocity distribution inside the tank for two different types of impellers layouts is investigated and the crude oil mixing time for these two arrangements is compared. The results show when the impellers are placed close to each other in one bottom quarter of the tank, mixing is more efficient in comparison with the distributed arrangement. When the tank is equipped with two and three impellers, the mixing performance is quite different in the two different orientations. However, in the five impellers cases, no considerable difference is observed except at the beginning and finishing parts of homogenization.

CFD simulation of homogenization in large-scale crude oil storage tanks

The homogenization time of two layers of crude oils obtained from different reservoirs in 19 000 m 3 floating roof storage tank is predicted using computational fluid dynamics (CFD). The tank equipped with a side-entry 0.65 m marine-type mixer. An in-house CFD code using Multiple Frame of Reference (MFR) and the renormalization group version (RNG) of k– ε turbulent model has been employed. The fluid region has been divided to 580 484 number of control volumes. The time variation of density at three sampling points in the tank has been compared with corresponding points in the model. The results show a good agreement.

An air quality emission inventory of offshore operations for the exploration and production of petroleum by the Mexican oil industry

Abstract An air quality screening study was performed to assess the impacts of emissions from the offshore operations of the oil and gas exploration and production by Mexican industry in the Campeche Sound, which includes the states of Tabasco and Campeche in southeast Mexico. The major goal of this study was the compilation of an emission inventory (EI) for elevated, boom and ground level flares, processes, internal combustion engines and fugitive emissions. This inventory is so far the most comprehensive emission register that has ever been developed for the Mexican petroleum industry in this area. The EI considered 174 offshore platforms, the compression station at Atasta, and the Maritime Ports at Dos Bocas and Cayo Arcas. The offshore facilities identified as potential emitters in the area were the following: (1) trans-shipment stations, (2) a maritime floating port terminal, (3) drilling platforms, (4) crude oil recovering platforms, (5) crude oil production platforms, (6) linking platforms, (7) water injection platforms, (8) pumping platforms, (9) shelter platforms, (10) telecommunication platforms, (11) crude oil measurement platforms, and (12) flaring platforms. Crude oil storage tanks, helicopters and marine ship tankers were also considered to have an EI accurate enough for air quality regulations and mesoscale modeling of atmospheric pollutants. Historical ambient data measure at two onshore petroleum facilities were analyzed to measure air quality impacts on nearby inhabited coastal areas, and a source–receptor relationship for flares at the Ixtoc marine complex was performed to investigate health-based standards for offshore workers. A preliminary air quality model simulation was performed to observe the transport and dispersion patterns of SO 2 , which is the main pollutant emitted from the offshore platforms. The meteorological wind and temperature fields were generated with CALMET, a diagnostic meteorological model that used surface observations and upper air soundings from a 4-day field campaign conducted in February of 1999. The CALMET meteorological output and the generated EI drove the transport and dispersion model, CALPUFF. Model results were compared with SO 2 measurements taken from the monitoring network at Dos Bocas.

Corrosion inhibition of steel in crude oil storage tanks

AbstractThe corrosion behavior of steel in water from certain oil fields with various organic inhibitors was studied by applying potentiodynamic technique at pH 5.9. The inhibitors which were used include 2‐methylbenzimidazole (I), 2‐mercaptobenzimidazole (II), 2‐mercapto‐5‐methylbenzimidazole (III), and 2‐mercaptothiazole (IV). The inhibiting efficiency of the different additives was evaluated from their anodic and cathodic polarization curves at different temperatures.A comparative study of curve fitting procedures using the kinetic thermodynamic model and those utilizing well‐known adsorption isotherms was undertaken. Three types of isotherms were used, Langmuir, Frumkin and Flory‐Huggins isotherm. The results show that the kinetic‐thermodynamic model and Flory‐Huggins isotherms are more suitable to fit the data for the four inhibitors, at all applied temperatures. From the values of binding constants, K, the order of inhibitor efficiency is:III > IV > II > Iand thus 2‐mercapto‐5‐methylbenzimidazole was the most effective inhibitor. The thermodynamic parameters obtained for all the compounds used showed low values of Hads, which indicates that the action of these inhibitors is physically adsorptive in nature.

Tank Atmosphere Perturbation: A Procedure for Assessing Flashing Losses from Oil Storage Tanks

A new procedure to measure the total volume of emissions from heavy crude oil storage tanks is described. Tank flashing losses, which are difficult to measure, can be determined by correcting this value for working and breathing losses. The procedure uses a fan or blower to vent the headspace of the storage tank, with subsequent monitoring of the change in concentrations of oxygen or other gases. Combined with a separate determination of the reactive organic carbon (ROC) fraction in the gas, this method allows the evaluation of the total amount of ROC emitted. The operation of the system is described, and results from measurement of several storage tanks in California oil fields are presented. Our measurements are compared with those obtained using the California Air Resources Board (CARB) 150 method.

Oilfield control system

Real-time control techniques for measuring parameters in crude oil storage tanks are described. The techniques enable the height of the oil/water layer in the storage tanks to be measured. By using this measuring technique for the oil-water interface, with the height of the interface in the tanks, coupled with the measurements of the water/oil content ratio, the density and flow rate of crude oil and the net oil quantity can be calculated. Therefore, automatic online computation of crude oil reserves and gross output quantity of net oil can be accurately predicted. The proposed method solves a difficult oil field problem that enables control of oil and gas production volumes to be maintained, particularly in low temperature environments where conventional instrumentation has proved ineffective. The control techniques enable the oil production process to function safely and reliably.

Oil Field Hydrogen Sulfide in Texas: Emission Estimates and Fate

Hydrogen sulfide is released into the atmosphere during oil recovery operations. However, little is quantitatively known concerning the total sulfur flux due to these fugitive emis sions. A mobile laboratory, equipped to measure atmospheric gases and meteorological parameters, was used to collect quantitative data in the vicinity of various oil field operations. Fugitive emissions of H2S and soil sulfate levels were studied. Concentrations of atmospheric sulfur gases (SO2, H2S, mercaptans) were measured in the oil-producing regions of several west Texas counties. Hydrogen sulfide was by far the dominant reduced sulfur gas in all locations. Except in the vicinity of refining/processing plants, mercaptan levels were below 200 pptv. Sulfur dioxide levels were also very low, typically below 200 pptv. In all locations, a strong diurnal pattern of the ambient H2S concentration was observed. Specific sources, the flux, and the fate of the H2S emitted in oil field operations was studied. Crude oil storage tanks w...

CHARACTERIZATION OF SLUDGE WAXES FROM CRUDE OIL STORAGE TANKS HANDLING OFFSHORE CRUDE

ABSTRACT The 300°C+ and 500°C+ vacuum residues of the sludge obtained from offshore crude oil storage tanks located at our onshore facilities have been subjected to dewaxing using MBK solvent. The yield of the refined waxes were 45.38% and 43.13% (sludge basis) and melting points 92-93°C and 95-96°C respectively The waxes were mainly n-parafTins. Their simulated boiling point distribution analysis reveals a distinct himodal distribution of n-paraffins, the even carbon number homologucs between C50, to C60 being present at preferentially higher ratio(l.4:1) than the odd ones. The present finding are expected to improve the understanding of waxes present in offshore crude. It is also expected to help in devising process to refine waxes of lank bottom sludge.

ATTCO PIPELINE TANK FIRE: RESPONDING TO THE VOLCANIC INFERNO

ABSTRACT On a hot afternoon in June 1995, lightning struck a 55,000-barrel crude oil storage tank owned by ATTCO Pipeline Company in Addington, Oklahoma. The lightning strike subsequently caused a fire and explosion that ultimately resulted in the collapse of the tank. During the initial response efforts, specialized fire-fighting equipment and personnel were requested from Sheppard Air Force Base out of Wichita Falls, Texas. Unfortunately, efforts to extinguish the fire resulted in a tragic loss of life. This poster seeks to examine the sequence of events leading up to the loss of life and to discuss how these events affected the overall spill response efforts. It will include an analysis of the operational parameters established by ATTCO's Facility Response Plan that was in effect on June 10, 1995, and will also examine the state of preparedness and prevention efforts leading up to June 10, 1995. Ultimately, this poster will determine what effect, if any, the state of readiness had on the events of that day.

Microbiological profile of crude oil in storage tanks

Microbiological quality of crude oil storage tanks was determined. The samples were taken from crude oil storage tanks in three stations, at Ughelli, Escravos and Forcados tank farms in the Delta State of Nigeria. Two tanks were sampled at each station with samples collected from three levels of the tank, namely the oil layer, oil water interface, and effluent layer. Samples from the inner walls and bottom sediment of the only empty tank in Ughelli during the study were also taken. The total heterotrophic count of bacteria and total fungal count were obtained by plating samples on nutrient agar and sabouraud's glucose agar respectively and incubated for 14 days at 28 °C±2 °C. Oilutilizing bacteria and fungi were isolated on oil agar using fungizone and antibiotics to inhibit fungal and bacterial growth respectively. Pure cultures of bacteria and fungi were prepared on nutrient agar and sabouraud's glucose agar respectively at 28 °C±2 °C for 4 days. Isolates were identified using approved standard methods. Three bacterial genera, Pseudomonas, Proteus and Bacillus, and one actinomycete, Actinomyces and two fungal genera, Penicillium and Cunninghamella, were isolated. Pseudomonas was dominant among the bacteria (41.62%) and Penicillium dominant among the fungi (94%). It was also found that the total microbial load of the effluent layer was higher than that of the oil layer.

HISTORICAL BUILDUP OF OIL SPILL RESPONSE CAPABILITY IN JAPAN

ABSTRACT With the large oil spill that occurred in 1971 as an impetus, Japan's Maritime Pollution and Disaster Prevention Law was amended in 1973 and subsequently in 1976. The amendments required owners of vessels and petroleum facilities to retain designated quantities of oil boom, sorbent, dispersant, and other items to minimize impact from spills. A large oil spill caused by a ruptured crude oil storage tank in 1974 led to the enactment of additional legislation: the Petroleum Complex Disaster Prevention Law. Under this, petroleum facilities are required to maintain designated quantities of oil boom, oil boom deploying vessels, skimming boats, and the like. These legislative measures, together with voluntary efforts, have contributed to a sound buildup of the nation's oil spill response force. However, the response capability including stockpiled materials and equipment has been designed primarily to cope with incidents in closed waters such as inland seas, bays, and ports, and hence not for a oil spill in open seas as large as that from the Exxon Valdez. As one of the measures under the 1990 International Convention for Oil Spill Preparedness, Response and Cooperation, the Government of Japan has entrusted the Petroleum Association of Japan with an oil spill response capability reinforcement project to cope with a large oil spill should one occur in Japanese waters or nearby seas. Under the scheme, during the 5 year period beginning in 1991, the Petroleum Association of Japan is scheduled to build up, using subsidies from the government, stockpiles of cleanup equipment and materials and to augment the existing response capability.

New designs of valves for storage tanks

Fire protection measures applied to KD type breather valves for crude oil and petroleum product storage tanks have resulted in increasing the valve metal content and in difficulties in their production and operation. Three new valves, designated KSD-50, KSD-150, and KDS-1000, were developed by the Ufa Branch of the All-Union Research of Petroleum Machinery to eliminate these shortcomings. The KDS-1000, an automated double-action valve, was designed for tanks of medium capacity which operate under severe climatic conditions. Specifications of the three valves are tabulated and the KDS-1000 is illustrated.

Causes, mechanisms and prevention of internal corrosion in storage tanks for crude oil and distillates

This paper deals with the causes and mechanisms of internal corrosion of tanks used for the storage of crude oil and distillates. Services which are considered in this paper include crude oil storage tanks, gasoline blending and/or storage tanks and storage tanks for kerosene and heavier distillates. Fixed‐roof, as well as floating‐roof tanks, are considered. Methods for corrosion prevention and control are discussed.

DEGRADATION OF HYDROCARBON SLUDGES IN THE SOIL

Hydrocarbon residues from crude oil storage tanks were incorporated into field plots of a Red River Clay soil. The oil content immediately after application was 1.45% based on the weight of air-dried soil. The plots were sampled after application and after 106, 476 and 833 days. Hydrocarbons were extracted from samples with tetrahydrofuran at room temperature and fractionated by a combination of solvent extraction and column chromatography into the following fractions: (1) saturates, (2) monoaromatics, (3) diaromatics, (4) polyaromatics and polar compounds and (5) high molecular weight material such as asphaltenes. Fractions (1) to (4) were examined by gas–liquid chromatography. The results showed that 50.4% of the total applied residues were degraded within 833 days. The individual fractions were degraded to varying extents: (1) 54.6%, (2) 50.0%, (3) 57.1%, (4) 44.4% and (5) 11.1%. The alkanes in fraction (1) degraded to low levels during the first 106 day s.