Crude Oil Storage Tanks Research Articles

Heat flow coupling characteristics analysis and heating effect evaluation study of crude oil in the storage tank different structure coil heating processes

Considering the factors such as ambient temperature, solar radiation, heating steam pressure and physical properties of oil products, a theoretical model for heating process of large floating roof tank coil is established. The numerical solution technology of the crude oil temperature field and flow field is studied to reveal the coupling characteristics of crude oil heat transfer and flow during the storage tank heating process. Furthermore, the influence law of different coil structures on the temperature field and flow field during the crude oil heating process is discussed. On this basis, the evaluation indexes of the heating effect on the crude oil storage tank is set up, which are combined with heating rate and uniform degree of temperature field. The results show that according to variations of crude oil flow field in the tank, the tank steam coil heating process has been divided into four stages including natural convection formation, small vortex formation, large vortex formation and large vortex development. The coil structures have great influence on the temperature field and the flow field of the crude oil tank. The vertical structure and the stereoscopic structure coils will form a certain thickness low temperature zone at the tank bottom during heating process, but the serpentine structure coil will form a heated dead zone at vertex angle and base corner of the tank where area is relatively small. On this basis, comparing the heating effect of the three kinds of coils, it is found that the heating rate of serpentine structure coil is the fastest and more stable. The uniform degree of temperature field is affected by the oil liquid level. Environmental temperature and other factors have little effect and the best heating effect.

Investigation of the pyrophoric tendency of the powder of corrosion products in an oil tank

The pyrophoric tendency of the powder of corrosion products and deposits in oil tanks was investigated by performing several series of tests in a modified self-heating experimental apparatus based on the crossing point temperature method. Three samples of the powder of corrosion products and deposits in oil tanks as well as a ferrous sulfide were used as test samples. The corresponding apparent activation energies (Eas) were obtained: 26.1 kJ mol−1 for the corrosion products of a crude oil storage tank, 27.2 kJ mol−1 for the middle distillate oil storage tanks, and 43.5 kJ mol−1 for ferrous sulfide; the unexposed cross-point for deposits of a crude oil storage tank was at a temperature below 250 °C. Those values of Eas indicated that the corrosion products of the two oil storage tanks showed a stronger pyrophoric tendency than did the deposits of the crude oil storage tanks and ferrous sulfide. Furthermore, the Ea values were similar to those of reactions reported for the incomplete oxidation of hydrogen sulfide (H2S), thus supporting the viewpoint that H2S may be considered the intermediate product for accelerating the self-heating and self-ignition of sulfide at temperatures below 250 °C and may play a major role in inducing fires and explosions in storage oil tanks. In addition, possible sources of H2S in self-heating of the corrosion product were largely caused by thermochemical sulfate reduction or thermal decomposition of the organic matter of oil tanks.

Investigation of factors affecting on viscosity reduction of sludge from Iranian crude oil storage tanks

Crude oil is a kind of water/oil emulsion, which the oil phase consists of organic molecules with different molecular weights such as alkanes, paraffin, asphaltene, and resins. Due to the change in physicochemical conditions during the production, transportation, storage, and refining, heavier molecules can precipitate from crude oil. Thus, viscous sludge formed at the bottom of storage tanks can cause many problems including reduction of storage capacity of tank, oil contamination, corrosion, repair costs, environmental pollution, etc. The reduction of sludge viscosity can be achieved by reduction of its interfacial tension. In this study, different chemical and physical factors, influencing prepared emulsions (made of sludge, water and surfactant), such as surfactants, solvents, temperature, pressure, and mixing conditions were investigated. Results showed that non-ionic surfactants (like bitumen emulsifier), and solvents (such as mixed xylene, AW-400, and AW-402), injection of additives, applying pressure, and mixing operations had a positive effect on reduction of emulsion viscosity. All experiments were carried out with sludge obtained from crude oil storage tanks at Kharg Island, Iran.

Evaluation of a sequential biotrickling–biofiltration unit for removal of VOCs from the headspace of crude oil storage tanks

AbstractBACKGROUNDPetrochemical refineries and production sites are considered to be the second greatest source of VOC emissions after vehicle exhausts. The feasibility and performance of a novel sequential biotrickling‐biofiltration unit for the treatment of a mixture of VOCs in the headspace of an oil and gas production tank battery was evaluated for three months at the Apache TAMU#2 well storage tank battery in Snook, Texas.RESULTSThe results demonstrated that the main VOC constituents of the headspace of the storage tanks were alkanes along with smaller amounts of aromatics such as benzene, toluene and xylenes. Monitoring results for the biotreatment unit showed an average removal efficiency of 50–60% at an empty bed residence time of 120 s in each tank of the unit. After inoculation of the system with wastewater from a sedimentation basin of a local refinery, the removal efficiency of the system increased dramatically which demonstrated the importance of inoculation to achieve a rapid and successful start‐up in industrial biofilters. The most optimal performance was achieved after 77 days, obtaining the highest elimination capacity of 23 g m‐3 h‐1 at total VOCs loading rate of 39 g m‐3 h‐1.CONCLUSIONThe operation of the field‐scale sequential BTF‐BF unit for more than three months demonstrated the robustness of this technology and the degradation capabilities of a combination of the suspended and attached growth treatment. The project results demonstrated the potential for even more optimization for improved effectiveness of this novel biological treatment technology for removal of highly variable aromatic VOC concentrations. © 2017 Society of Chemical Industry

Calculation and Comparison of Parameters during Fire in Large Capacity Crude Oil Storage Tanks

Calculation and Comparison of Parameters during Fire in Large Capacity Crude Oil Storage Tanks

Optimization of combined in-vessel composting process and chemical oxidation for remediation of bottom sludge of crude oil storage tanks

ABSTRACTIn this research, removal of petroleum hydrocarbons from oily sludge of crude oil storage tanks was investigated under the optimized conditions of in-vessel composting process and chemical oxidation with H2O2 and Fenton. After determining the optimum conditions, the sludge was pre-treated with the optimum state of the oxidation process. Then, the determined optimum ratios of the sludge to immature compost were composted at a C:N:P ratio of 100:5:1 and moisture content of 55% for a period of 10 weeks. Finally, both pre-treated and composted mixtures were again oxidized with the optimum conditions of the oxidants. Results showed that total petroleum hydrocarbons (TPH) removal of the 1:8 and 1:10 composting reactors which were pre-treated with H2O2 were 88.34% and 90.4%, respectively. In addition, reduction of TPH in 1:8 and 1:10 composting reactors which were pre-treated with Fenton were 83.90% and 84.40%, respectively. Without applying the pre-treatment step, the composting reactors had a removal rate of about 80%. Therefore, pre-treatment of the reactors increased the TPH removal. However, post-oxidation of both pre-treated and composted mixtures reduced only 13–16% of TPH. Based on the results, remarkable overall removal of TPH (about 99%) was achieved by using chemical oxidation and subsequent composting process. The study showed that chemical oxidation with H2O2 followed by in-vessel composting is a viable choice for the remediation of the sludge.

Corrosion Protection of Crude oil or Product Storage Tanks- Front End Designs (FEED)

Corrosion Protection of Crude oil or Product Storage Tanks- Front End Designs (FEED)

English

This paper presents a procedure in format of a flowchart for prover sizing based on API-MPMS Standard which can be considered as a pattern for prover sizing in field prover design and fabrication. The method was analyzed and verified for the prover of the biggest crude oil fiscal metering system in Iran, that is, bidirectional field prover of Genaveh 10 Million BBL Crude Oil Storage Tanks Fiscal Metering System Project which was designed and fabricated by Asia Instruments Co. LTD. Since this prover was designed to calibrate both heavy and light crude oil fiscal metering systems, each comprised five Ultrasonic Liquid Flow Meters of Faure Herman Co., API MPMS standard requirements for ultrasonic liquid meters were also considered in prover sizing presented method. Results indicate how commercially optimum prover dimensions can be obtained based upon project specifications and other equipment of fiscal metering system and prover. Key words: Prover sizing, ultrasonic flow meter, detector switch.

Corrosion behavior of the high strength low alloy steel joined by vertical electro-gas welding and submerged arc welding methods

The high strength low alloy (HSLA) steel used as a large crude oil storage tank (LCOST) was often welded by vertical electro-gas welding (VEGW) and submerged arc welding (SAW). The VEGW specimen was produced by single-pass weld with high heat input (about 100KJ/cm), and the SAW specimen was manufactured by mutil-pass weld with low heat input (about 30KJ/cm). The corrosion behaviors of both samples were studied by electrochemical techniques and surface methods. The research results achieved in this investigation disclosed that the welding process played an important role in obtaining satisfactory corrosion property. In comparison with the SAW joint, the VEGW joint showed uniform microstructure and coarse micro-phase. The scanning vibrating electrode technique (SVET) results demonstrated that the corrosion of the VEGW joint majorly took in the heat effect zone (HAZ) and the attack for the SAW joint mainly occurred in the fusion zone (FZ). In addition, the scanning electron microscopy (SEM) results exhibited that the VEGW joint exhibited a light local attack and the SAW joint demonstrated a heavy uniform corrosion. The electrochemical results showed that the VEGW joint showed lower corrosion rate than the SAW joint. In summary, it can be discovered that the corrosion rates of welded specimens were associated with the welding-pass and the corrosion forms of welded specimens were related to the heat input energy.

Solvent Blend Performance in Hydrocarbon Recovery from Nigerian Tank Bottom Sludge

Oil sludge waste associated with crude oil production generally consists of oil, sands and untreatable emulsions segregated from the production stream, and sediment accumulated on the bottom of crude oil and water storage tanks. The use of single solvent and combination (solvent blend) was evaluated for extraction of hydrocarbon content (oil) of the Tank Bottom Sludge (TBS) associated with the crude oil production with a view to optimizing hydrocarbon recovery from the sludge. TBS samples were contacted with selected solvents blends of varying volumetric ratios, each at a time. The blend generated from xylene, hexane, cyclohexane and petroleum ether representing aliphatic and aromatic interactive combination with varying polarity. Their effects on the oil recovery from tank bottom sludge were determined, with solubility parameter as a factor. The optimum oil recovery by blend A, B and C at room temperature of 29°C, from sample 1 are respectively 54.48% (3:2), 60.33% (2:3) and 61.10% (1:1); from Sample 2, were respectively 66.25% (2:3), 60.80 (3:2) and 63.35 (1:1) at room temperature of 29°C . At room temperature Blend C has the highest performance in extracting oil from sample 1. The highest performance in recovery of oil from sample 2 was observed with blend A (66.25 %.). Solvent extraction process is very effective in recovering hydrocarbons oil from TBS. The use of solvents mixture greatly improved oil recovery from TBS and varies with blend composition and the operating temperature condition.

Solvent Blend Performance in Hydrocarbon Recovery from Nigerian Tank Bottom Sludge

Oil sludge waste associated with crude oil production generally consists of oil, sands and untreatable emulsions segregated from the production stream, and sediment accumulated on the bottom of crude oil and water storage tanks. The use of single solvent and combination (solvent blend) was evaluated for extraction of hydrocarbon content (oil) of the Tank Bottom Sludge (TBS) associated with the crude oil production with a view to optimizing hydrocarbon recovery from the sludge. TBS samples were contacted with selected solvents blends of varying volumetric ratios, each at a time. The blend generated from xylene, hexane, cyclohexane and petroleum ether representing aliphatic and aromatic interactive combination with varying polarity. Their effects on the oil recovery from tank bottom sludge were determined, with solubility parameter as a factor. The optimum oil recovery by blendA,BandCat room temperature of 29°C, from sample 1 are respectively 54.48% (3:2), 60.33% (2:3) and 61.10% (1:1); from Sample 2, were respectively 66.25% (2:3), 60.80 (3:2) and 63.35 (1:1) at room temperature of 29°C . At room temperature BlendChas the highest performance in extracting oil from sample 1. The highest performance in recovery of oil from sample 2 was observed with blendA(66.25 %.). Solvent extraction process is very effective in recovering hydrocarbons oil from TBS. The use of solvents mixture greatly improved oil recovery from TBS and varies with blend composition and the operating temperature condition.

Microwave pyrolysis of oily sludge with activated carbon

ABSTRACTThe aim of this study is to explore catalytic microwave pyrolysis of crude oil storage tank sludge for fuels using granular activated carbon (GAC) as a catalyst. The effect of GAC loading on the yield of pyrolysis products was also investigated. Heating rate of oily sludge and yield of microwave pyrolysis products such as oil and fuel gas was found to depend on the ratio of GAC to oily sludge. The optimal GAC loading was found to be 10%, while much smaller and larger feed sizes adversely influenced production. During oily sludge pyrolysis, a maximum oil yield of 77.5% was achieved. Pyrolytic oils with high concentrations of diesel oil and gasoline (about 70 wt% in the pyrolytic oil) were obtained. The leaching of heavy metals, such as Cr, As and Pb, was also suppressed in the solid residue after pyrolysis. This technique provides advantages such as harmless treatment of oily sludge and substantial reduction in the consumption of energy, time and cost.

원유저장탱크 방류벽의 콘크리트 바닥재 불침투성 세부기준 연구

원유저장탱크 방류벽의 콘크리트 바닥재 불침투성 세부기준 연구

Investigating the effect of vibration on corrosion rate of crude oil storage tanks

The present paper, deals with the influence of vibration and temperature on corrosion rate of ASTM A537 carbon steel used for crude oil storage tanks of Basrah oil fields in south Iraq. A mechanical vibration system equipped with temperature controller according to ASTM G32 standards test method was used to test and study the effect of vibration and temperature on the corrosion rates using immersion test method. Three types of crude oils: light, medium, and heavy crude oils were collected from tanks in southern Iraq. The experimental immersion test results demonstrated that the vibration increases the corrosion rate compared to static case. The light crude oil show larger values of corrosion and heavy crude oil show smaller values, while medium crude oil show moderate values.

Impact of Crude Oil Storage Tank Emissions and Gas Flaring on Air/Rainwater Quality and Weather Conditions in Bonny Industrial Island, Nigeria

This study investigated the effects of gaseous emissions from crude storage tank and gas flaring on air and rainwater quality in Bonny Industrial Island. Ambient air quality parameters, rainwater and weather parameters were collected at 60 m, 80 m, 100 m, 200 m and control plot for 4 weeks at the Bonny. Rainwater parameters were investigated using standard laboratory tests. Data analyses were done using Analysis of variance, pairwise t-test and Pearson’s correlation statistical tools. Results show that emission rates, volatile organic compound (VOC) noise and flare temperature decreased with increasing distance from flare points and crude oil storage tanks. Findings further revealed the emission rates varied significantly with distance away from the gas flaring point (F = 6.196; p = 0.004). The mean concentration of pollutants between gas flare site and crude oil storage tank showed that CO (0.02 ± 0.001 - 0.002 ±0.001), SPM (0.011 ± 0.001 - 0.01 ± 0.001), VOC (0.005 ± 0.001 - 0.01 ± 0.001) and NO2 (0.04 ± 0.001 - 0.005 ± 0.000) had significant variations (p > 0.05) with CO, O3 and NO2 having higher concentrations at the gas flare site while SPM, and VOC were higher around the crude oil storage tank site. Wind turbulence was higher around the gas flaring point (4.93 TKE) than the crude oil storage tank (4.55 TKE). Similarly, there was significant variation in the sun radiation, precipitation, and wind speed caused by gas flaring (1582.25 w/m2, 436.25 mm, 0.53 m/s) and crude oil storage tank (1536.25 w/m2, 3.91.41 mm, 0.51 m/s). There were also significant variations in flared temperature (F = 22.144; p = 0.001); NO2 (F = 8.250; p = 0.001), CO (F = 6.000; p = 0.004) and VOC (F = 5.574; p = 0.006) with distance from the gas flaring point. The variation in the rainwater parameters with distance from the gas flaring indicated significant variations in pH (F = 5.594; p = 0.006). The study showed that the concentration of VOC and particulates were high in the supposedly control area which is perceived to be safe for human habitation. Significant variations exist in emission rate (p = 0.015), flare temperature (p = 0.001), NO2 (p = 0.003), VOC (p = 0.001), noise (p = 0.041), hydrogen carbonate (p = 0.037) and chromium (p = 0.032) between the gas flaring and crude oil storage tank. Regular monitoring is advocated to mitigate the harmful effects of the pollutants.

Assisted bioremediation tests on three natural soils contaminated with benzene

Bioremediation is an attractive and useful method of remediation of soils contaminated with petroleum hydrocarbons because it is simple to maintain, applicable in large areas, is economic and enables an effective destruction of the contaminant. Usually, the autochthone microorganisms have no ability to degrade these compounds, and otherwise, the contaminated sites have inappropriate environmental conditions for microorganism’s development. These problems can be overcome by assisted bioremediation (bioaugmentation and/or biostimulation). In this study the assisted bioremediation capacity on the rehabilitation of three natural sub-soils (granite, limestone and schist) contaminated with benzene was evaluated. Two different types of assisted bioremediation were used: without and with ventilation (bioventing). The bioaugmentation was held by inoculating the soil with a consortium of microorganisms collected from the protection area of crude oil storage tanks in a refinery. In unventilated trials, biostimulation was accomplished by the addition of a nutrient mineral media, while in bioventing oxygen was also added. The tests were carried out at controlled temperature of 25 oC in stainless steel columns where the moist soil contaminated with benzene (200 mg per kg of soil) occupied about 40% of the column’s volume. The processes were daily monitored in discontinued mode. Benzene concentration in the gas phase was quantified by gas chromatography (GC-FID), oxygen and carbon dioxide concentrations were monitored by respirometry. The results revealed that the three contaminated soils were remediated using both technologies, nevertheless, the bioventing showed faster rates. With this work it was proved that respirometric analysis is an appropriate instrument for monitoring the biological activity.

Application Model Analysis on Automatic System of Fire Detection, Alarming and Extinguishment in Crude Oil Storage Tank

In order to realize functions of automatic monitoring, alarming and extinguishment on fire in crude oil storage tank, the paper came up with a fire detection model with multisensor, including selective module with fire feature combination, supervised training module and fire detection module. By regarding PNN as a classifier to carry out tests on effectiveness of the model, the conclusions that the model can reduce the influence of fire parameters’ fluctuation on detection results was drew. Moreover, an excellent fault-tolerant ability was possessed at the same time. Through some confirmatory experiments, The phenomenon was reached that two kinds of parameters in adoptive four parameters have no normal fire signal, but the model still can greatly distinguish from correct fire state.

Reinforcement Effect of Vibration Replacement Stone Column Test in Test Pile Area for One Crude Oil Business Reserve Base

The crude oil storage tank foundation is always treated by using vibration replacement stone column composite foundation treatment, mainly to improve the engineering properties of foundation soil and the deformation properties of soil, improving the bearing capacity of composite foundation, and to ensure the normal use of tank in the superstructure loads from damage or excessive deformation. Before construction to carry out the vibration replacement stone column composite foundation pile test, the test shows that strengthening the foundation bearing capacity characteristic value of vibration replacement stone column can meet the design requirements.

Application of Hydrogen Peroxide and Fenton as Pre- and Post-treatment Steps for Composting of Bottom Sludge from Crude Oil Storage Tanks

In this research the feasibility of chemical oxidation with H2O2 and Fenton's reagent for degradation of petroleum hydrocarbons before and after composting of bottom sludge from crude oil storage tanks was investigated. Results showed that total petroleum hydrocarbons removal in composting reactor was 80.2%. In chemical oxidation steps, petroleum hydrocarbons removal enhanced with increasing oxidant concentrations. Increasing oxidation time from 24 to 48 h had a little effect on petroleum hydrocarbons removal. The study showed that chemical oxidation as a pre-treatment step was more effective than post-treatment. It was also deduced that petroleum hydrocarbons in the sludge and composted mixture can be oxidized by hydrogen peroxide without adding supplementary iron.

Safety Assessment of Large-Scale Crude Oil Tank after Fire Process

In recent years, the demand of the crude oil is increasing in the world, and the oil storage tanks are also developing larger and larger. Higher requirements of safety for storage tank, especially safety evaluation of the oil tanks in fire environment, was proposed because the oil tank volume is large, as well the oil is volatile, flowing, inflammable and explosive easily. In the paper, the fire process was simulated by the heat treatment for the key position, and the relationship between mechanical property and heating temperature of large tank after fire was obtained. The strength evaluation for large-scale crude oil storage tank after fire was implemented and the result showed that the strength for large crude oil tank was satisfied with requirement.