Quantitative research of the liquid film characteristics in upward vertical gas, oil and water flows

The study of liquid film characteristics in multiphase flow is a very important research topic, however,the characteristics of the liquid film around Taylor bubble structure in gas, oil and water three-phase flow are not clear. In the present study, a novel liquid film sensor is applied to measure the distributed signals of the liquid film in three-phase flow. Based on the liquid film signals, the liquid film characteristics including the structural characteristics and the nonlinear dynamics characteristics in three-phase flows are investigated for the first time. The structural characteristics including the proportion, the appearance frequency and the thickness of the liquid film are obtained and the influences of the liquid and gas superficial velocities and the oil content on them are investigated. To investigate the nonlinear dynamics characteristics of the liquid film with the changing flow conditions, the entropy analysis is introduced to successfully uncover and quantify the dynamic complexity of the liquid film behavior.

Investigation of oil and water migrations in lacustrine oil shales using 20 MHz 2D NMR relaxometry techniques

The behavior of oil and water in tight rocks can change the distribution of oil or water in pores,which affects the production of crude oil.Nuclear Magnetic Resonance(NMR)method is an effective and nondestructive tool for evaluating rocks with comparison and analysis both quantitatively and qualitatively.In our study,20 MHz NMR Relaxometry is used as a key technique to study the changes of water and oil behaviors in Chinese lacustrine Qingshankou shales under different saturated states(imbibition and evaporation without pressure).The results show that variation in different proton populations(water,oil and organic)can be distinguished using 2D T_(1)-T_(2)maps.The comparison among T_(1)-T_(2)maps with different saturated states shows that different signal regions changed during oil and water migrations,which the 1D NMR Relaxometry may be not easy to approach.Combined with the pyrolysis analysis,T2 shift and differences of signal regions in T_(1)-T_(2)maps can reflect properties such as wettability and composition(organic matter,clay and magnetic minerals)to some extent.This study provides better insight into oil and water behaviors in lacustrine oil shales with further understanding of 20 MHz NMR 2D T_(1)-T_(2)maps both in qualitative and quantitative analysis.

NUMERICAL SIMULATION ANALYSIS FOR MIGRATION-ACCUMULATION OF OIL AND WATER

Numerical simulation of oil migration and accumulation is to describe the history of oil migration and accumulation in basin evolution. It is of great value in the exploration oil resources and their rational evaluation. This paper, puts forward the mathematical model and the modified method of alternating direction implicit interactive scheme. For the famous hydraulic experiment of secondary migration_accumulation (cut plane and plane problem), it has been done the numerical simulation test, and both the computational and experimental results are identical.

Study on polyurethane-based porous materials and their adsorption properties

The flexible superhydrophobic thermoplastic polyurethane(TPU)porous material was prepared by heat-induced phase separation method with two cooling steps.The influence of the preparation process on the microstructure of the material was discussed in depth.The microstructure,hydrophobicity and specific surface area of porous TPU materials were analyzed in detail.The surface wettability,separation selectivity,saturated adsorption capacity and adsorption rate,mechanical properties,environmental adaptability and cyclic properties of porous TPU materials were studied.The results show that the TPU-8%porous monolithic material prepared by heat-induced phase separation method shows good performance when the polymer concentration is 8%,the phase separation temperature is 0℃,the phase separation time is 30min,and the mixing solvent ratio is 9:1.

Measurement of oil-water flow via the correlation of turbine flow meter, gamma ray densitometry and drift-flux model

The flow rate of the oil-water horizontal flow is measured by the combination of the turbine flow meter and the singlebeam gamma ray densitometry. The emphasis is placed on the effects of the pipe diameter, the oil viscosity and the slip velocity on the measurement accuracy. It is shown that the mixture flow rate measured by the turbine flow meter can meet the application requirement in the water continuous pattern（ o- w flow pattern）. In addition, by introducing the developed drift-flux model into the measurement system, the relative errors of measurements for component phase flow rates can be controlled within ±5%. Although more accurate methods for the flow rate measurement are available, the method suggested in this work is advantageous over other methods due to its simplicity for practical applications in the petroleum industry.

The prediction of spontaneous oil-water imbibition in composite capillary

In view of the classical Lucas-Washburn equation,which can only describe the spontaneous imbibition of single wetted capillary,a tilted composite capillary model with circular cross section,composed of different wettability capillary wall was established.The model can describe the spontaneous oil-water imbibition of water-wet capillary,oil-wet capillary and mixed wetting capillary.Through numerical solution of the model equation,it is found that the component content of the capillary walls,the capillary radius and the oil-water viscosity ratio have great effects on the spontaneous oil-water imbibition.Effects of capillary inclination angle and inertia force on spontaneous oil-water imbibition are related to the capillary scale.Effects of capillary inclination angle and inertia force can be ignored in small radius capillary,while effects of inclination angle and inertia force can not be ignored in large radius capillary.

A novel composite coating mesh film for oil-water separation

Polytetrafluoroethylene-polyphenylene sulfide composite coating meshfilm was successfully prepared by a simple layered transitional spray-plasticizing method on a stainless steel mesh.It shows super-hydrophobic and super-oleophilic properties.The contact angle of this meshfilm is 156.3°for water,and close to 0°for diesel oil and kerosene.The contact angle hysteresis of water on the meshfilm is 4.3°.The adhesive force between thefilm and substrate is grade 0,theflexibility is 1 mm and the pencil hardness is 4H.An oil-water separation test was car-ried out for oil-contaminated water in a six-stage super-hydrophobicfilm separator.The oil removal rate can reach about 99%.

Facile Preparation of Fluoroalkyl End-Capped Vinyltrimethoxysilane Oligomer/Sand Composites Possessing Superoleophilic/Superhydrophobic Characteristic: Application to Oil/Water Separation and Selective Removal of Fluorinated Aromatic Compounds from Aqueous Methanol Solution

Fluoroalkyl end-capped vinyltrimethoxysilane oligomer [RF-(CH2-CHSi(OMe)3)n-RF: n = 2, 3, RF = CF(CF3)OC3F7: RF-(VM)n-RF], was applied to the facile preparation of the corresponding oligomer/sand (Ottawa sand: OS) composites [RF-(VM-SiO3/2)n-RF/OS] through the sol-gel reaction of the oligomer in the presence of micro-sized OS particles (590 - 840 μm) under alkaline conditions at room temperature. FE-SEM (Field Emission Scanning Electron Micrograph) images showed that the obtained composites consist of the RF-(VM-SiO3/2)n-RF oligomeric nanoparticles and the micro-sized OS particles. Interestingly, the RF-(VM-SiO3/2)n-RF/OS composites thus obtained can provide the superoleophilic/superhydrophobic characteristic on the composite surface, applying to the separation of not only the mixture of oil/water but also the W/O emulsion to isolate the transparent colorless oil. The fluorinated oligomeric OS composites were also found to be applicable to the selective removal of fluorinated aromatic compounds from an aqueous methanol solution. Especially, it was demonstrated that the fluorinated OS composites can supply a higher efficient and smooth separation ability for the separation of the mixture of oil and water than that of the corresponding fluorinated micro-sized controlled silica gel (μ-SiO2) composites (average particle size: 9.5 μm), which were prepared under similar conditions. In addition to the separation of oil/water, the fluorinated OS composites provided higher and more selective removal ability for the fluorinated aromatic compounds from aqueous solutions than that of the μ-SiO2 composites.