scholarly journals Combined Treatment (Alkali + Thermal) of Calotropis procera Fiber for Removal of Petroleum Hydrocarbons in Cases of Oil Spill

Polymers ◽  
2021 ◽  
Vol 13 (19) ◽  
pp. 3285
Author(s):  
Raoni Batista dos Anjos ◽  
Larissa Sobral Hilário ◽  
Aécia Seleide Dantas dos Anjos ◽  
Emily Cintia Tossi de Araújo Costa ◽  
Tarcila Maria Pinheiro Frota ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Contact Angle ◽  
Sorption Capacity ◽  
Oil Spill ◽  
Combined Treatment ◽  
Calotropis Procera ◽  
Internal Diameter ◽  
Oil Viscosity ◽  
Sorption System ◽  
Fiber Oil

The objective of this study was to evaluate the Calotropis procera fiber treated with NaOH combined with heat treatment as sorbent material for removal of petroleum and derivatives in cases of oil spill. The effects of oil viscosity, fiber/oil contact time, and the type of sorption system (oil and oil/water) were evaluated by experimental planning. The fiber obtained was characterized by Fourier transform infrared spectroscopy (FTIR), field-emission scanning electron microscopy (SEM-FEG), thermogravimetric analysis (TG/DTG), contact angle, and wettability. The fiber treated by combining NaOH and heat treatment (CPNaOHT) exhibited a large structure with an internal diameter of 42.99 ± 3.98 μm, roughness, and hydrophobicity on the surface with a contact angle of 101 ± 2°. The sorption capacity of oil ranged from 190.32 g/g to 98.9 g/g. After five cycles of recycling, the fiber still maintains about 70% of its initial sorption capacity and presented low liquid desorption (0.25 g). In this way, it can be used as an efficient sorbent to clean up spills of oil and oil products.

scholarly journals Dual Electrochemical Treatments to Improve Properties of Ti6Al4V Alloy

Materials ◽  
2020 ◽  
Vol 13 (11) ◽  
pp. 2479
Author(s):  
Stefano Rossi ◽  
Luciana Volgare ◽  
Carine Perrin-Pellegrino ◽  
Carine Chassigneux ◽  
Erick Dousset ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Combined Treatment ◽  
Amorphous Film ◽  
Amorphous Layer ◽  
Good Alternative ◽  
Surface Treatments ◽  
Ex Situ ◽  
X Ray Diffraction ◽  
Transmission Electron ◽  
Fluid Environment

Surface treatments are considered as a good alternative to increase biocompatibility and the lifetime of Ti-based alloys used for implants in the human body. The present research reports the comparison of bare and modified Ti6Al4V substrates on hydrophilicity and corrosion resistance properties in body fluid environment at 37 °C. Several surface treatments were conducted separately to obtain either a porous oxide layer using nanostructuration (N) in ethylene glycol containing fluoride solution, or bulk oxide thin films through heat treatment at 450 °C for 3 h (HT), or electrochemical oxidation at 1 V for 3 h (EO), as well as combined treatments (N-HT and N-EO). In-situ X-ray diffraction and ex-situ transmission electron microscopy have shown that heat treatment gave first rise to the formation of a 30 nm thick amorphous layer which crystallized in rutile around 620 °C. Electrochemical oxidations gave rise to a 10 nm thick amorphous film on the top of the surface (EO) or below the amorphous nanotube layer (N-EO). Dual treated samples presented similar results with a more stable behavior for N-EO. Finally, for both corrosion and hydrophilicity points of view, the new combined treatment to get a total amorphous N-EO sample seems to be the best and even better than the partially crystallized N-HT sample.

Experimental Analysis of Water/Oil Displacement Tests in Horizontal Pipe

SPE Journal ◽  
2021 ◽  
pp. 1-18
Author(s):  
Roberto Fernando Leuchtenberger ◽  
Jorge Luiz Biazussi ◽  
William Monte Verde ◽  
Marcelo de Souza Castro ◽  
Antonio Carlos Bannwart
Keyword(s):  
Viscous Liquid ◽  
High Speed ◽  
Cold Water ◽  
Tap Water ◽  
Logistic Function ◽  
Oil Field ◽  
Injection Velocity ◽  
Internal Diameter ◽  
Oil Viscosity ◽  
Horizontal Pipe

Summary Production shutdowns occur often throughout the life cycle of an oil field. In offshore fields, shutdown situations are accompanied by an intense heat exchange between pipeline and cold water, which exponentially increases oil viscosity. Such an event may lead to serious difficulty to restart the production, or even render it unfeasible, especially for heavy oil fields. Therefore, a preventive procedure is required to remove the ultraviscous oil from pipelines and risers; for example, by pumping diesel or methanol in a flush procedure. Designing an efficient cleanup procedure is therefore essential in terms of time, amount of fluid injected, and pumping system requirements. However, the amount of research published in this area is limited. In this paper, we propose a comprehensive analysis on how the displacement of a viscous liquid by a less-viscous liquid occurs in a pipeline through footages in different segments, varying the injection velocity. Two mineral oils with different viscosities and tap water were used as working fluids for this study. The experimental setup was built with a horizontal 10-m-long acrylic pipe with 19-mm internal diameter. Two high-speed cameras were placed both in the inlet and outlet segments. Our results demonstrate how water displaces viscous oil in a pipeline, showing different flow configurations as superficial water velocity increases, depending on the oil viscosity and distance from the inlet. A dimensionless analysis was performed by a combination of the forces that govern the flow and dimensionless groups found in literature. The results show an expected area of optimum values regarding cleaning time according to flow configuration. A unidimensional model using a logistic function was proposed and showed a good agreement with the experimental data. The model itself proven to be an easy tool for industry and academic purposes, supporting even more robust and elaborated models in the future. NOTE: Supplemental material is available with this paper and is available online under the Supplementary Data heading at https://doi.org/10.2118/205356-PA.

scholarly journals Effects of 2.45-GHz Electromagnetic Fields with a Wide Range of SARs on Micronucleus Formation in CHO-K1 Cells

2004 ◽  
Vol 4 ◽  
pp. 29-40 ◽  
Author(s):  
S. Koyama ◽  
Y. Isozumi ◽  
Y. Suzuki ◽  
M. Taki ◽  
J. Miyakoshi
Keyword(s):  
Heat Treatment ◽  
Electromagnetic Fields ◽  
Cell Damage ◽  
Combined Treatment ◽  
Chinese Hamster ◽  
Positive Control ◽  
Dependent Manner ◽  
Temperature Dependent ◽  
Chromosomal Breakage ◽  
Wide Range

There has been considerable discussion about the influence of high-frequency electromagnetic fields (HFEMF) on the human body. In particular, HFEMF used for mobile phones may be of great concern for human health. In order to investigate the properties of HFEMF, we have examined the effects of 2.45-GHz EMF on micronucleus (MN) formation in Chinese hamster ovary (CHO)-K1 cells. MN formation is induced by chromosomal breakage or inhibition of spindles during cell division and leads to cell damage. We also examined the influence of heat on MN formation, since HFEMF exposure causes a rise in temperature. CHO-K1 cells were exposed to HFEMF for 2 h at average specific absorption rates (SARs) of 5, 10, 20, 50, 100, and 200 W/kg, and the effects on these cells were compared with those in sham-exposed control cells. The cells were also treated with bleomycin alone as a positive control or with combined treatment of HFEMF exposure and bleomycin. Heat treatment was performed at temperatures of 37, 38, 39, 40, 41, and 42°C.The MN frequency in cells exposed to HFEMF at a SAR of lower than 50 W/kg did not differ from the sham-exposed controls, while those at SARs of 100 and 200 W/kg were significantly higher when compared with the sham-exposed controls. There was no apparent combined effect of HFEMF exposure and bleomycin treatment. On heat treatment at temperatures from 38–42°C, the MN frequency increased in a temperature-dependent manner. We also showed that an increase in SAR causes a rise in temperature and this may be connected to the increase in MN formation generated by exposure to HFEMF.

Combined treatment of green pitch pine wood by heat and superheated steam and the effects on physical properties of the products

Holzforschung ◽  
2014 ◽  
Vol 68 (3) ◽  
pp. 327-335 ◽  
Author(s):  
Yonggun Park ◽  
Chang-Deuk Eom ◽  
Yeonjung Han ◽  
Jun-Ho Park ◽  
Yoon-Seong Chang ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Physical Properties ◽  
Large Scale ◽  
Superheated Steam ◽  
Bending Strength ◽  
Combined Treatment ◽  
Decay Resistance ◽  
Green Wood ◽  
Heat Treated ◽  
Pitch Pine

Abstract Pitch pine (P. rigida) wood was treated with superheated steam (SHS) and the subsequent effects due to drying and heat treatment (HT) were observed. The following treatment parameters were tested: 180°C air HT, 220°C air HT, 0.1 MPa–180°C SHS HT, 0.1 MPa–220°C SHS HT, 0.5 MPa–180°C SHS HT, and 0.5 MPa–220°C SHS HT. No drying checks were observed in the specimens (500×150×50 mm3) treated at 0.5 MPa–220°C SHS and with these treatment parameters, equilibrium moisture content (EMC) was the lowest. Low EMC has an effect on physical properties such as shrinkage, compressive strength parallel to the grain, bending strength, hardness, and decay resistance. Based on the results, it is expected that the green wood in a large scale is possible to be simultaneously dried and heat-treated without occurrence of checks by the SHS HT process.

scholarly journals Evaluation of Thermally Treated Calotropis Procera Fiber for the Removal of Crude Oil on the Water Surface

Materials ◽  
2019 ◽  
Vol 12 (23) ◽  
pp. 3894
Author(s):  
Sobral Hilário ◽  
Batista dos Anjos ◽  
Borges de Moraes Juviniano ◽  
da Silva
Keyword(s):  
Crude Oil ◽  
Sorption Capacity ◽  
Low Cost ◽  
Water Layer ◽  
Petroleum Products ◽  
Calotropis Procera ◽  
Oil Removal ◽  
Oil Sorption ◽  
Static Systems ◽  
Thermally Treated

Biosorbents have been highlighted as an alternative method for the removal of contaminants from spills or leaks of oil and its derivatives, since they are biodegradable, are highly available, low-cost, and have a good sorption capacity. This research investigated the sorption capacity of Calotropis procera fiber in natura (CP) and thermally treated (150 °C and 200 °C) for crude oil removal and recovery. The oil sorption tests were carried out in a dry and water (layer) static systems. The assays revealed that CP fiber has excellent hydrophobic-oil properties and good crude oil sorption capacity, about 75 times its own weight (76.32 g/g). The results of the treated fibers, CPT150 and CPT200, showed oil sorption capacities (in 24 h) higher than CP, between 94.31–103.37 g/g and 124.60–180.95 g/g, respectively. The results from sample CPT200 showed that it can be an excellent biosorbent for the removal of crude oil and other derivatives due to its high hydrophobicity, great reuse/resorption capacity, and ability to retain oil within the fiber lumens. Thus, it can be applied in the recovery, cleaning, and removal of petroleum products and its derivatives from spills and leaks in the future.

scholarly journals Functionalized Surface Layer on Poplar Wood Fabricated by Fire Retardant and Thermal Densification. Part 2: Dynamic Wettability and Bonding Strength

Forests ◽  
2019 ◽  
Vol 10 (11) ◽  
pp. 982 ◽  
Author(s):  
Demiao Chu ◽  
Jun Mu ◽  
Stavros Avramidis ◽  
Sohrab Rahimi ◽  
Shengquan Liu ◽  
...  
Keyword(s):  
Contact Angle ◽  
Surface Layer ◽  
Surface Energy ◽  
Bonding Strength ◽  
Sessile Drop ◽  
Combined Treatment ◽  
Treated Wood ◽  
Fire Retardant ◽  
Tangential Section ◽  
Droplet Volume

In continuation of our former study on a novel combined treatment of nitrogen–phosphorus fire retardant and thermomechanical densification on wood, this study focuses on the dynamic wettability and the bonding strength. The contact angle was measured using the sessile drop method and the surface energy was calculated according to the van Oss method. Water surface penetrating and spreading is analyzed by both the Shi and Gardner model and the droplet volume changing model. The results reveal that the combined treatment increased the surface energy, especially the acid–base component. The contact angle declined and the water droplet spread more easily on the surface. Meanwhile, the rate of relative droplet volume decreased by 32.6% because the surface layer was densified and stabilized by the combined process. Additionally, the surface possesses the lowest roughness and highest abrasion resistance on the tangential section. Thus, the bonding strength of the combined treated poplar decreased by 29.7% compared to that of untreated poplar; however, it is still 53.3% higher than that of 220 °C heat-treated wood.

Increased Inactivation of Ozone-Treated Clostridium perfringens Vegetative Cells and Spores on Fabricated Beef Surfaces Using Mild Heat†

2004 ◽  
Vol 67 (2) ◽  
pp. 342-346 ◽  
Author(s):  
JOHN S. NOVAK ◽  
JAMES T. C. YUAN
Keyword(s):  
Heat Treatment ◽  
Clostridium Perfringens ◽  
Combined Treatment ◽  
Ozone Treatment ◽  
Combined Treatments ◽  
Vegetative Cells ◽  
Initial Concentration ◽  
Subsequent Heating ◽  
Confocal Fluorescence ◽  
Margin Of Safety

Ozone treatment of beef surfaces enhanced the effectiveness of cooking temperatures ranging from 45 to 75°C against enterotoxin-producing strains of Clostridium perfringens. Vegetative cells on beef surfaces at an initial concentration of 5.59 ± 0.17 log CFU/g were reduced significantly (P < 0.05) to 4.09 ± 0.72 log CFU/g and 3.50 ± 0.90 log CFU/g after combined treatments with aqueous ozone (5 ppm) and subsequent heating at 45 and 55°C, respectively. Spores on the beef surface were likewise significantly reduced from an initial concentration of 2.94 ± 0.37 log spores per g to 2.07 ± 0.38 log spores per g and 1.70 ± 0.37 log spores per g after the combined treatment with aqueous ozone (5 ppm) and subsequent heating at 55 and 75°C, respectively. Fluorescent nucleic acid stains were used with confocal fluorescence microscopy to show that spores remaining attached to the meat were protected from treatment-specific injury. This study provides evidence for the decreased resistance of both vegetative cells and spores of C. perfringens with ozone treatment that is followed by heat treatment at temperatures that would not otherwise be as effective, thus lowering the requirements for cooking beef while maintaining a margin of safety.

scholarly journals Reversible Superwetting Transition Between Superhydrophilicity and Superhydrophobicity on a Copper Sheet, and Its Corrosion Performance

2021 ◽  
Vol 8 ◽  
Author(s):  
Hong Li ◽  
Tiange Chen ◽  
Yanfeng Lu ◽  
Xinyu Fu ◽  
Xingwen Chu ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Contact Angle ◽  
Superhydrophobic Surfaces ◽  
Corrosion Performance ◽  
Copper Sheet ◽  
Water Contact ◽  
Good Corrosion Resistance ◽  
Whole Process ◽  
Potentiodynamic Polarization Curves ◽  
Surface Modified

Dense copper oxide nanoribbons arrays are prepared on a copper sheet by using a low-temperature hydrothermal method. The wettability of the surface modified by stearic acid is superhydrophobic, and the water contact angle is 153.6°. It is demonstrated that the reversible transition from superhydrophilicity to superhydrophobicity is successfully achieved by heat treatment and re-modification, and the whole process can be accomplished in 170 s. Potentiodynamic polarization curves and Nyquist curves show that these superhydrophobic surfaces have good corrosion resistance and superior durability.

scholarly journals AN INTEGRATED MODELING APPROACH FOR SIMULATING OIL SPILL AT THE STRAIT OF BOHAI SEA

2012 ◽  
Vol 1 (33) ◽  
pp. 33 ◽  
Author(s):  
Jinhua Wang ◽  
Jinshan Zhang
Keyword(s):  
Oil Spill ◽  
Bohai Sea ◽  
Oil Spills ◽  
Three Dimensional ◽  
Coupling Model ◽  
Temporal Variations ◽  
Oil Viscosity ◽  
Vertical Diffusion ◽  
Particle Tracking Method ◽  
Oil Particles

A three–dimensional integrated model is developed for simulating oil spills transport and fate in seas. The model contains two main modules, flow and transport-fate module. The transport module uses an unstructured finite volume wave-current coupling model, giving a more accurate result compared to structured model, especially for a region has a complex coastline. In the transport-fate module the oil dispersion is solved using a particle-tracking method. Horizontal diffusion is simulated using a random walk techniques in a Monte Carlo framework while vertical diffusion process is solved based on the Langeven equation. The model simulates the most significant processes which affect the motion of oil particles, such as: advection, surface spreading, evaporation, dissolution, emulsification, and turbulent diffusion, the interaction of the oil particles with the shoreline, sedimentation and the temporal variations of oil viscosity, density, and surface-tension. This model has been applied to simulate the oil spill accident at the strait of Bohai Sea. In comparison with the observations, the numerical results indicate that the model is reasonably accurate.

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