Rayleigh-Bénard convection of a model emulsion: anomalous heat-flux fluctuations and finite-size droplets effects

We present mesoscale numerical simulations of Rayleigh-Bénard (RB) convection in a two-dimensional model emulsion. The systems under study are constituted of finite-size droplets, whose concentration Ψ0 is systematically varied from...

Influence of Particle Size Distribution of the Filtering Loading on the Size of Particles of A Disperse Phase of an Emulsion

Oil emulsions are formed in the course of oil production, transportation, storage and a wash of oil tanks. Some oil emulsions are highly dispersed and rather stable for division by methods of upholding, centrifugation and flotation. In work for effective division of an oil model emulsion the method of a contact coalescention received the filtering loadings from a granular and porous polytetrafluoroethylene (PTFE). Speed of filtration of a model oil emulsion through the filtering loading depending on the size of granules of PTFE is determined. Extent of division of an emulsion at filtration through loading with a size of granules of 0,5 mm of high, 89% for porous and 74,4% for granular PTFE, but with increase in the size of granules of the filtering loading extent of division of an emulsion decreases. The initial model emulsion is polydisperse system with sizes of particles of 567 - 3315 nanometers. After filtration through PTFE granules the size of particles of a disperse phase decreases, particles of oil coalesce and are late in a time, in a surface and space between granules. It is confirmed by formation of oil slicks on the surface of the filtering loading. And the size of granules of the filtering loading is less; the size of particles in an emulsion filtrate is less. By results of a research influence of particle size distribution of the filtering loading on the size of particles of a disperse phase of a filtrate of an emulsion is defined.

Performance and Selectivity of Ceramic Membranes in the Ultrafiltration of Model Emulsion in Saline

Oily wastewaters from different onshore and offshore installations and from maritime transport pose a serious threat to the environment so they must be treated by multistage separation also including membrane processes. The main advantages of such membranes are high performance and selectivity, high resistance for temperature and pressure, resistance for acids, bases and solvents, long service life and for application - significant reduction of industries and transport environmental impact. This work presents the results of the process of separation of oil from the emulsion with NaCl addition. Research was performed with a use of laboratory installation with ceramic 300 kDa membrane. The analysis concerned performance and selectivity of a membrane in the function of time and test results have been subsequently compared with the requirements of the IMO.