Wet Oil Research Articles

Dewatering behavior of wet oil palm sawn timber during flat compression

ABSTRACT One obstacle to the industrial processing of oil palm wood is its nearly water-saturated state in green condition and its high tendency to develop cell collapse during kiln drying. This study analyzed mechanical dewatering by flat compression as an alternative pre-drying method for wet oil palm sawn timber. In the process, boards 700 mm long were compressed at ratios of 40% and 60% using a laboratory press, which resulted in water extraction of the free water varying between 38–52% and 60–73%, respectively. Since unperforated press plates were used, the water could only escape over the crosscut and long edges. The extent to which the crosscut and long edges were involved in dewatering was examined, and found to depend on the position of the board in the trunk due to the different water permeability conditions at the different heights. Permeability measurements, therefore, were carried out on cylindrical specimens using a specifically designed testing device. For the analysis of the hydrostatic pressure development in the boards, three pressure transducers were installed at different distances to the crosscut at half board thickness. The analysis of the recovery of compression showed, that the boards recovered to a large extend immediately after compression.

Physicochemical characterisation and kinetic modelling of wet torrefied oil palm trunk in pyrolysis condition

AbstractOver 218 million tonnes of oil palm trunks (OPT) waste is produced annually by Malaysian oil palm industry, which can be converted to biofuels via wet torrefaction. This study assessed the fuel characteristics of wet torrefied OPT (WT‐OPT) using proximate analysis, higher heating value (HHV) analysis, Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy–energy dispersive X–ray spectroscopy (SEM–EDX). Increasing wet torrefaction temperature and residence time increased the fixed carbon content and HHV of OPT. SEM–EDX revealed the presence of microspheres of 5‐hydroxymethylfurfural (5‐HMF) in OPT wet torrefied at 180 and 220°C for 72 h, an intermediate compound that can contribute to the HHV enhancement in WT‐OPT. FTIR and EDX results revealed that higher temperature and residence time concentrate the carbon content of OPT. Wet torrefaction at 180°C for 72 h decreased the activation energy and pre‐exponential factor of OPT from 301.88 to 171.70 kJ mol−1 and from 4.43 × 1028 to 3.25 × 1012 s−1, respectively, during pyrolysis. The estimated thermodynamic parameters, particularly the change in entropy which generally decreased by more than 140 J mol−1 K−1, indicated increase in stability of certain WT‐OPT.

Экспериментальное исследование применимости методик определения коэффициента сжимаемости природного газа в области низких температур

The article is devoted to the analysis of compressibility factor calculation methods in the temperature range from 220 to 250 K. The AGA8-92DC (GOST 30319.2- 96), AGA8 Report Detail (GOST 30319.3-2015), GERG-2004/2008, NX19, GERG-91, ISO 20765-1 (GOST R 8.662-2009), GSSSD MR 118-05 (moderately compressed gas mixtures) and GSSSD MR 113-03 (Wet Oil Gas) methods are experimentally tested. Deviations of experimental data and calculated values of compressibility coefficient determined by the specified methods are shown. It is found out that the deviation of the calculated values of the compressibility factor according to the AGA8-92DC, AGA8 Report 1 Detail, GERG-2004/2008, ISO 20765-1 (GOST R 8.662-2009), GSSSD MR 13-03 methods from the experimental ones does not exceed 0,1 %. This fact confirms the possibility of using these methods in the temperature range from 220 to 250 K. The results obtained in the framework of this study are highly significant for flow metering, and in particular, provide an increase in the accuracy of the procedure for bringing the volume of natural gas to standard conditions at low temperatures.

Features of removal of coloring substances during bleaching vegetable oils

In modern conditions of vegetable oil processing, the issues of improving the quality and safety of refined oils remain relevant. It has been noted that the most effective one is complex or complete refining of vegetable oils, which ensures the removal of the main groups of related substances by traditional and improved methods. The complexity of the organization of refining technology is associated with the accompanying oxidation of oils at certain stages and a decrease in their resistance to oxidation during storage. Moreover, this is most characteristic of the time-consuming operation of adsorption bleaching when using acidactivated mineral adsorbents containing active metals that contribute to the activation of oxidative processes. A new approach to the organization of the technology of removing coloring substances during bleaching involves the use of a «wet» method of clarification of hydrated wet oil. This technology helps to reduce the oxidation of bleached oil at a high level of clarification. The effectiveness of the method is increased due to the use of a mixture of mineral and vegetable adsorbents, the bleaching ability of which is enhanced by the use of mechanochemical activation (MHA). It has been noted that a plant adsorbent obtained from dried crushed pea leaves containing pectin and hemicellulose is effective. MHA contributes to the complex effect on the treated system due to local pressures and shear deformations, which activate the adsorption properties of the modified mineral-vegetable adsorbent and increases its selective effect. The proposed technology using a mixture of sorbents and MHA increases the resistance of oil to oxidation and reduces the accumulation of oxidation products in it during storage, it improves the quality of bleached oil, which should provide a high effect of the final stage of complete refining – deodorization.

Comparative assessment of liquid sloshing in dry and wet storage tank of floating offshore platform

In order to explore the characteristics of the single-layer liquid sloshing in offshore dry oil storage tank and the two-layer liquid sloshing in offshore wet oil storage tank, two series of experiments were carried out: one was free surface sloshing in a closed rectangular tank partially filled with colored water, and the other was interfacial sloshing in the identical tank but completely filled with white oil and colored water. The tank was mounted on a shake table and was subjected to harmonic horizontal excitation with different excitation amplitudes and a wide range of excitation frequencies, including the first seven natural modes of single-layer or two-layer liquid system. The present study find that the frequency responses of interfacial sloshing wave are analogous to those of the free surface sloshing wave, but smaller in amplitudes. The experiments also produce results that are unique to the two-layer liquid sloshing. For example, when the external excitation frequency is equal to or close to the odd mode natural frequency of two-layer liquid system, a complicated three-dimensional (3D) gravity-capillary wave might be generated at the oil-water interface. Finally, the comparisons of free surface and interfacial sloshing in the viscous damping ratio, higher sloshing modes, impact pressure amplitude and mass center displacement were conducted, which revealed the superiority of wet storage technology in structural safety and dynamic stability.

Research on Optimal Oil Filling Control Strategy of Wet Clutch in Agricultural Machinery

To improve the wet clutch engagement quality, which is widely used in agricultural machinery, the oil filling control strategy of a wet clutch is studied based on the method of simulation and experiment in detail in this paper. Firstly, this paper carries out the dynamic analysis of the wet clutch engagement process, establishes the mathematical model of the mechanical domain and the hydraulic domain of the hydraulic execution system, and designs the backstepping oil pressure controller. The controllability of the output oil pressure of the clutch hydraulic actuator is verified on the joint simulation platform of Matlab/Simulink (Version R2017b, MathWorks, Natick, MA, USA) and AMESim (Version 2019.1, Simcenter Amesim, Siemens Digital Industries Softwares, Berlin&Munuch, Germany). Then, this paper analyzes the clutch engagement process, extracts five factors affecting the oil filling process, and selects four clutch engagement quality evaluation indexes. An amount of 50 groups of experiments are carried out on the wet clutch oil filling test simulation platform built by SimulationX (Version 3.8, ESI ITI GmbH, Dresden, Germany). The response surface method (RSM) and stepwise regression analysis method are used to explore the mathematical models of the quality evaluation index and influencing factors of the oil filling process. Through 15 groups of random tests, the prediction accuracy of the stepwise regression model and the RSM model of each index is compared, and the models with high accuracy are selected to establish the comprehensive prediction mathematical model of clutch engagement quality, combined with the variance weight method. Finally, according to the working condition of the 3 MPa oil filling pressure studied in this paper, the optimal oil filling control strategy is obtained by the proposed clutch engagement quality prediction model. Under the target condition, when the oil filling rate of stage 1 is the highest and the proportion of phase 1’s duration to the total oil filling time is 69.65%, the oil filling rate of stage 2 is the lowest and the proportion of phase 2’s duration to the total oil filling time is 21.85%, and the proportion of phase 3’s duration to the total oil filling time is 8.51%, the engagement quality of wet clutch is the best. The research method of wet clutch optimal oil filling control strategy proposed in this paper provides a reliable method for the ride comfort research of agricultural machinery and clutch control.

Valorization of Wet Oily Petrochemical Sludge via Slow Pyrolysis: Thermo-Kinetics Assessment and Artificial Neural Network Modeling

Oily sludge is a hazardous waste stream of oil refineries that requires an effective process and an environment-friendly route to convert and recover valuable products. In this study, the pyrolytic conversion of the wet waste oil sludge was implemented in an autoclave pyrolyzer and a thermogravimetric analyzer (TGA) at 5°C/min, 20°C/min, and 40°C/min, respectively. The kinetic analysis was performed using model-free methods, such as Friedman, Kissenger–Akahira–Sunose (KAS), and Ozawa–Flynn–Wall (OFW) to examine the complex reaction mechanism. The average activation energy of wet waste oil sludge (WWOS) estimated from Friedman, KAS, and OFW methods was 198.68 ± 66.27 kJ/mol, 194.60 ± 56.99 kJ/mol, and 193.28 ± 54.88 kJ/mol, respectively. The activation energy increased with the conversion, indicating that complex multi-step processes are involved in the thermal degradation of WWOS. An artificial neural network (ANN) was employed to predict the conversion during heating at various heating rates. ANN allows complex non-linear relationships between the response variable and its predictors. nH, ΔG, and ΔS were found to be 191.26 ± 2.82 kJ/mol, 240.79 ± 2.82 kJ/mol, and −9.67 J/mol K, respectively. The positive values of ΔH and ΔG and the slightly negative value of ΔS indicate the endothermic nature of the conversion process, which is non-spontaneous without the supply of energy.

Study of a solar installation for olive mill sludge treatment

Olive mill sludge treatment was performed using a parabolic trough solar collector (PTC) to supply thermal energy. The proposed prototype, composed of a drying chamber coupled with a heat exchanger and a PTC, allows the treatment of up to 80 kg of wet olive oil pomace in about 1 hour and 40 min, the equivalent of 112 tons during the post-production period of olive oil. Due to the presence of oil, which delays evaporation, the drying process was studied at relatively high temperatures between 120 and 140 °C. The obtained results show that the effective diffusivities varied from 2.59 10−7 to 1.36 10−6 m²/s with an activation energy of 27.9 kJ/mol. The sludge dryer performance has also been analyzed and optimized numerically with MATLAB software. The indirect solar dryer using a PTC showed a relevant level of stability, fewer temperature fluctuations, and better control of the drying parameters compared to the direct solar dryer. The overall analysis reveals that the maximum thermal efficiency of 43% was recorded with total thermal energy produced throughout the year of 23,909 kWh, while the Levelized cost of heat was 0.34 $/kWhth. The proposed system leads to the avoidance of about 15,900 kg of CO2 emissions.

Multi-slice Ni-doped brochantite modified and polymer crosslinked cellulose paper with high wet stability and oil repellency for water disposal

Cellulose paper (CP) is an environmentally-friendly and low-cost material, but its application in petrochemical water disposal is limited by poor wet stability and oil repellency. In this work, based on the crosslinking and low-temperature hydrothermal reaction, we report a novel CP material which is crosslinked by polyethyleneimine (PEI)-glutaraldehyde (GA)-cellulose and modified by Ni-doped brochantite crosslinked CP (NB-PCCP) for the removal of emulsified oils and dyes in wastewater. The crosslinking process enhances the wet strength of CP, and the formation of the multi-slice structure of Ni-doped brochantite on PCCP surface improves the oil repellency. Results show that NB-PCCP possesses outstanding oil-in-water emulsion separation performance with high oil rejection of 99.9%, the Young's modulus of NB-PCCP is quadruple that of untreated CP in wet conditions, indicating improved wet stability in practice application. NB-PCCP also displays excellent removal performance for dyes due to the existence of high-density hydroxyl radicals, as well as excellent acid/alkali resistance. The research on CP provides significant guidance for the design of cellulose-based material with multi-slice structure as well as high wet strength and oil repellency for the purification of wastewater.

The Impact of Different Types of Hydrocarbon Disturbance on the Resiliency of Native Desert Vegetation in a War-Affected Area: A Case Study from the State of Kuwait.

This study assesses the impact of total petroleum hydrocarbon (TPH) concentration and soil parameters (heavy metals, chemical properties, and water-soluble boron) on the succession process of vegetation survival in the Al-Burgan oil field in Kuwait. A total of 145 soil samples were randomly collected from the three main types of hydrocarbon contamination, including dry oil lake (DOL), wet oil lake (WOL), and tarcrete. Sampling was also extended to noncontaminated bare soils that were considered reference sites. Remote-sensing data from Sentinel-2 were also processed to assess the level of contamination in relation to soil surface cover. The results showed that TPH concentration was significantly higher in WOL and DOL (87,961.4 and 35,740.6 mg/kg, respectively) compared with that in tarcrete (24,063.3 mg/kg), leading to a significant increase in soil minerals and heavy metals, greater than 50 mg/kg for Ba, and 10 mg/kg for V, Zn, Ni, and Cr. Such high concentrations of heavy metals massively affected the native vegetation’s resiliency at these sites (<5% vegetation cover). However, vegetation cover was significantly higher (60%) at tarcrete-contaminated sites, as TPH concentration was lower, almost similar to that in uncontaminated areas, especially at subsurface soil layers. The presence of vegetation at tarcrete locations was also associated with the lower concentration of Ba, V, Zn, Ni, and Cr. The growth of native vegetation was more likely related to the low concentration of TPH contamination at the subsurface layer of the soils in tarcrete sites, making them more suitable sites for restoration and revegetation planning. We concluded that further investigations are required to provide greater insight into the native plants’ phytoextraction potential and phytoremediation.

Synthesis and Evaluation of Local De-emulsifiers with Field Assessment in Iraqi Oil Fields

De-emulsifiers are one of the important industrial additives used commonly in petroleum industry in order to separate the salt water from crude oil essential the wet crude oil fields in south oil company (B.O.C) in Iraqi fields. De-emulsifiers activities due to the ability of these additives for breaking the thin film between dispersed phase and continuous phase globules in order to obtain two immiscible phase via the adsorption mechanism of the surfactants. In the present study has prepared local demulsifies by synthesis Gemini surfactants bis (Quaternary ammonium salt). The local de-emulsifier was assess in the laboratories of South Oil Company (B.O.C) Comparison with the results of commercial de-emulsifier (A), where the local material efficiency was higher than the important commercial (A) adopted in the B.O.C by bottle Test and later was produced (26) barrels of material prepared and evaluated in AL-SHAMIA Degassing station in Iraqi South Rumaila in (B.O.C). Where, evaluated the local de-emulsifier in the fields and show the positive results, this describes the evaluation of field emulsifying the local material in this study with lost cost of preparation of a one barrel about 500$ in the time that the cost of one barrel of commercial de-emulsifier is 1000$. The assessment was in the conditions of commercial de-emulsifier, depending on the natural of Dehydrator and Desalter in addition of the effective Dose is 25ppm and by 100% separation efficiency in same fresh oil source. The efficiency of local de-emulsifier studied Varity of parameters like: Temperature and the time required to separation function of the Dose. The field evaluation conditions of local de-emulsifier were under control outside of the oils (fresh) of D2 (Desalter) of isolation units to examine all of the water and salt content of crude oil. This was prepared for export according to the approved evaluation criteria compared with the commercial de-emulsifier imported and used in the oil sector.

Preparation of De-emulsifier of Gemini Surfactant &amp; it's Application in Oil Industry

A Gemini surfactants (GS) which are bis quaternary ammonium salt. It is prepared from tetramethyl ethylene diamine (TMEDA) with cetyl bromide, while an ordinary surfactant (OS),which is quaternary ammonium salt, is prepared from trimethyl amine (TMA) and cetyl bromide. They were identified by elemental analysis and IR spectroscopy.&#x0D; Comparing the GS,OS and the commercial surfactants, the Gemini surfactant shows an interesting properties and have a variety of uses, such as a De-emulsifier.&#x0D; Adopting the composition ratios found in the study of reverse chemistry of commercial De-emulsifier, Rp 6000, which is usually use in the south and north oil companies in Iraq. The prepares active gradients were characterized by various techniques, IR spectroscopy, elemental analysis, melting point, solubility, flash point and functional group analysis.&#x0D; &#x0D; The efficiency of the prepared De-emulsifier was examined by standard methods and compared with the efficiency of commercial Rp 6000 based on the same wet crude oil sources.

Treating Wet Oil in Amara Oil Field Using Nanomaterial (SiO2) With Different Types of De emulsifiers

One of the most important problems in the oil production process and when its continuous flow, is emulsified oil (w/o emulsion), which in turn causes many problems, from the production line to the extended pipelines that are then transported to the oil refining process. It was observed that the nanomaterial (SiO2) supported the separation process by adding it to the emulsion sample and showed a high separation rate with the demulsifiers (RB6000) and (sebamax) where the percentage of separation was greater than (90 and 80 )% respectively, and less than that when dealing with (Sodium dodecyl sulfate and Diethylene glycol), the percentage of separation was (60% and 50%) respectively.&#x0D; The high proportion of (NaCl + distilled water) raises the probability of the separation efficiency as the separation was (88.5,79)% and (65.5, 55) % for (RB6000, SebaMax)respectively with (SiO2) at 70 °C, while the results of separation were (77,85)% and (65,40) for (RB6000, Seba Max) respectively with (SiO2) at 50 °C after 120 minutes, where the (w/o ratio) was (9:1) for the high separation results and (7:3) for the lower separation results, at a speed of (12000rpm), and with a salt concentration of (1500) ppm, and less of these results at lower volumetric and temporal conditions. The (NaCl) salt deals with the wall films separating the droplets and reduces their viscosity [1].&#x0D; As for the pH factor, it is at the value (2 and 3) represent a stable emulsion that is difficult to separate easily, but with the passage of raising the pH away from the acidic medium and near to the basic direction, a significant increase in the separation process was observed compared with the acidic medium at lower values, after 120 minutes the separation seemed to be good efficient, reaching (60 and 70) % respectively, while at the same time the emulsion reached a more efficient separation level with a pH of ( 8 and 7) equal to (80 and 87.3) %, at 50 °C with SebaMax demulsifier in presence of (SiO2), and with the same pH values, an increase was observed in the separation with the increase in temperature to (70 °C), then it returns to be a reverse emulsifier when the value exceeds (10) to (11, 12, 13).

Determining the Exposure of Benzene, Toluene, Xylene (in Condensate ) in a Chemical Laboratory of Natural Gas Company by Chemical Health Risk Assessment (CHRA)

Introduction: Chemical risk assessment is needed to find out how high the hazard level of chemicals in thelaboratory. This chemical health risk assessment will assess how often the chemical is exposed to workers,how much exposure it is so that the level of risk can be understood. The purpose of enabling decisions to bemade on appropriate control measure, training of employees, monitoring and surveillance activities as maybe required to protect the health of employees who may exposed by hazardous chemicals to health at work.Methods: This research is research with a qualitative approach. Based on the data collected, this study isobservational. This study uses the Chemical Health Risk Assessment (CHRA) method. This method is carriedout by identifying chemicals, determining Hazard Rating, evaluating exposure, assessing the adequacy ofthe control measures that have been carried out, concluding the CHRA results, and identifying the effortsthat need to be made.Result: In this study, there are three work units, namely a wet laboratory, oil laboratory, and gas laboratory.The chemicals analyzed are benzene, toluene, and xylene in the condensate. The hazardous chemical havesignificant risk now and already adequately controlled could increase in future (C2) which mean that theemployees are at risk due to hazardous chemicals and it adequately controlled but the risk can increase inthe future.Conclusion : Therefore, several steps can be taken to control the risk of health hazards from benzene,toluene, and xylene in the condensate, for example: determine precaution to maintain controls and minimizechances of higher exposure occurring; determine additional measures for regaining control if a high-riskevent occurs despite precaution; identify measures, procedures, and equipment to prevent or control anyaccidental emission of chemical hazardous to health, determine if monitoring or health surveillance isrequired to check on the effectiveness of controls; and review assessment every five years or when is achange in circumstances

A new method to select demulsifiers and optimize dosage at wet crude oil separation facilities

The current practice for crude oil demulsifier selection consists of pre-screening of the best performing demulsifiers followed by field trials to determine the optimum demulsifier dosage. The method of choice for demulsifier ranking is the bottle test. As there is no standard bottle test method, there are different methodologies reported in the literature. In this work, a new approach to bottle test and field trial was described which improved significantly the selection and dosage of the demulsifier. The bottle test was optimized by measuring an accurate mass of demulsifier. This method produces repeatable results. This bottle-test methodology was benchmarked against field trial results performed in oil processing plants. The field trials were also improved to avoid the accumulation effect of demulsifier, when optimizing their dosage. The field data for the optimization of demulsifier dosage was analyzed mathematically; and a graphical method to determine the optimum range is described.

Behavior of Surfactants in Oil Extraction by Surfactant-Assisted Acidic Hydrothermal Process from Chlorella vulgaris.

The feasibility of surfactants for enhancement of extraction efficiencies in wet oil extraction through an acidic hydrothermal process was evaluated. Three different types of surfactants were tested: anionic (SDBS and SDS), cationic (CTAB and MBC), and non-ionic (IGEPAL CA-210 and Tween 60). The total fatty acid content of Chlorella vulgaris was 291.0 mg/g cell. Under the no-surfactant condition, the oil-extraction yield of the acidic hydrothermal extraction was 75.5%. The addition of SDBS and MBC at the 0.4% concentration showed enhanced oil-extraction performance, 85.4 and 85.7% yields, respectively. CTAB and Tween 60 showed low extraction yields, less than 43.0%. SDS and IGEPAL CA-210 showed high oil-extraction yields, higher, in fact, than the initial fatty acid content, due to surfactant partitioning into microalgal oil. With increasing surfactant concentration, the oil-extraction yields of CTAB decreased, those of IGEPAL CA-210 gradually increased, and those of SDBS increased and then decreased again. The best performance, an oil-extraction yield of 95.6%, was observed under the 0.2% SDBS, 120 °C, 1 h condition. Although IGEPAL CA-210 showed the high net oil-extraction yield of 98.3% at the 0.6% surfactant concentration, 61.2% of surfactant was partitioned into oil. Graphical abstract.

Evaluating the sustainability pillars of energy and environment considering carbon emissions under machining ofTi-3Al-2.5 V

This paper investigates the turning of Ti-3Al-2.5 V with coated carbide tools under different cooling/lubricating environments to identify the sustainable and improved cooling/lubrication technology. Five different cooling/lubrication conditions (dry, pressurized compressed air-assisted wet cooling, cooling with Ranque-Hilsch-vortex-tube (RHVT), conventional MQL, and wet oil cooling) were selected and turning performance was evaluated in terms of air quality of the worker’s breathable/working zone, energy consumption, carbon emissions, tool wear, surface roughness, and chips analysis. From experimentation, it was found that under MQL the value of tool wear and surface roughness was lowest as compared to other cooling/lubricating conditions. But the generation of particulate matter of PM2.5 (150–305 mg/m3) under MQL was on alarming scale as compared to other cooling/lubricating environments. Further, energy consumption and carbon emissions with MQL was found to be lowest followed by RHVT, which was mainly due to effective cooling/lubrication provided by the lubricant in MQL and chilled air under RHVT. The comparison of RHVT and MQL environments indicate just 1.6–1.4% increment in energy consumed with the use of RHVT under both tested speeds. Further, under RHVT state 45%–56% reduction in carbon emission (at both MRR) in contrast to dry turning was observed. The generation trend of average PM2.5 particles under RHVT was comparable with that achieved under dry conditions. Results of the study clearly indicates that RHVT can act as sustainable cooling/lubrication techniques in terms of environmental, economic and technological aspects for turning of Ti-3Al-2.5 V.

Bridging and discharge mechanisms of cellulose impurities in transformer oil under DC voltage

Cellulose impurities seriously threaten the insulating performance of oil-pressboard insulation. In this paper, we investigate the bridging and discharge mechanisms of cellulose impurities in transformer oil under DC voltage. The results show that under the non-uniform DC electric field, the cellulose impurities are mainly subjected to forces including gravity, buoyancy, dielectrophoretic force and drag force, among which the dielectrophoretic force dominates the bridging of the impurities. By studying the leakage current of dry (moisture 8 ppm) and wet (moisture 26 ppm) oil samples with and without cellulose bridges, deductions are made that the coexistence of cellulose and water in oil leads to the formation of a cellulose-water bridge, which increases the leakage current within the oil, causing a heating effect and gasifying the water on the bridge. Further analysis indicates that when the amount of gasified water exceeds the permeation channel threshold, the cellulose-water bridge transforms into a cellulose-gas bridge. Final oil breakdown happens along this gaseous bridge.

Evaluation of hydrocarbon broaching after subsurface containment failure, Gulf of Mexico

Broaching refers to the release of hydrocarbons at the seafloor after a loss of subsurface well containment. An underground blowout may allow migration of fluids upward through adjacent formations or the annulus to the seafloor. After the BP 001 Macondo well was capped, an oil slick was observed near the well. Available data were interpreted to determine if the slick was reservoir fluid broaching the seafloor or if it was a natural seep in the Gulf of Mexico. The experience revealed that no basis existed for estimating subsurface broach rates or how a potential to broach should be considered during well permitting decisions. Lawrence Berkeley National Laboratory (LBNL) modeled two broaching failure scenarios selected by the Bureau of Ocean Energy Management (BOEM) and representative of Gulf geosystems. Geoscientists from BOEM provided reservoir parameters and interpreted geologic surfaces from depth-migrated three-dimensional seismic volumes. The LBNL adapted existing supercomputing capabilities to model the traveltime for formation fluids to reach the seafloor after subsurface containment failure. The most sensitive parameters affecting traveltime are the mixture of formation fluids and the permeability of the geologic media through which it passes. Assuming nondepletion of reservoir pressure, gas-prone multiphase fluids may broach within a matter of decades. Wet oil and oil-prone multiphase fluids are slower by one to three orders of magnitude. The likelihood for the modeled systems to broach was mainly dependent on casing failure depth. The BOEM concluded that casing failures greater than 7500 ft (>2280 m) below mudline (seafloor) will not broach within a 6-month time frame of regulatory concern.

Stable cellular foams and oil powders derived from methylated microcrystalline cellulose stabilized pickering emulsions

The objective of this work was to methylate the microcrystalline cellulose (MCC) with methylcellulose (MC), investigate the ability of modified methylated MCC (Mmcc) to stabilize the emulsions and understand their role in the preparation of solid foams and oil powders. The Mmcc was prepared by thermally cross-linking MCC, and MC at 80 °C for 4 h followed by homogenization and lypholization without any additional wall materials. The FTIR spectroscopy confirmed an increase in the intensity of –CH2- associated band from 1400 cm−1 to 1456 cm−1 which corresponded to MCC and methylated MCC respectively. The methylation of the MCC with MC-a, MC-b, MC-c was evidenced by an increase in the particle size from 8.381 ± 0.17 to 12.41 ± 0.16, 12.51 ± 0.03, and 15.15 ± 0.75, respectively. The Mmcc and their corresponding emulsions expressed typical shear thinning behavior. The Pickering emulsions expressed improved resistance to environmental stresses and coalescence during storage. The microstructure of the solid foams observed with scanning electron microscopy revealed porous, spherical, polyhedral, and closely packed droplets. We found that the oil powders could be rehydrated in water. Their re-dispersibility index demonstrated that the wet oil powders attained re-dispersibility. The results open up new routes to engineer long term stabilization of the Pickering emulsions, solid foams, and oil powders for different applications.