Mechanical-physical separation sedimentation

Filtration is a physical separation whereby particles are removed from the fluid and retained by the filters. Three basic collection mechanisms involving fibers are inertial impaction, interception, and diffusion. In collection by inertial impaction, the particles with large inertia deviate from the gas streamlines around the fiber collector and collide with the fiber collector. In collection by interception, the particles with small inertia nearly follow the streamline around the fiber collector and are partially or completely immersed in the boundary layer region. Subsequently, the particle velocity decreases and the particles graze the barrier and stop on the surface of the collector. Collection by diffusion is very important for fine particles. In this collection mechanism, particles with a zig-zag Brownian motion in the immediate vicinity of the collector are collected on the surface of the collector. The efficiency of collection by diffusion increases with decreasing size of particles and suspension flow rate. There are also several other collection mechanisms such as gravitational sedimentation, induced electrostatic precipitation, and van der Waals deposition their contributions in filtration may also be important in some processes. 

The existence of the Black Sea bottom convective layer (BCL) has important implications for the physical and chemical exchange at the sediment/water interface and at the interface between intermediate and bottom water masses. Two-fold increased vertical gradients of dissolved sulphide at the upper boundary of the BCL suggest the presence of the anoxic interface separating entire anoxic water mass dominated by turbulent diffusion from underlying waters of the BCL where double diffusion is the main mixing mechanism. 

Contraryto the above-mentioned mechanical Solids-Liquid Separation modes like pressing, filtration or sedimentation where both materials maintain then-physical conditions, occurs during the drying process a phase transition of the liquid phase into a gaseous stage. 

The most straightforward means of physical treatment involves phase separation of the components of a mixture that are already in two different phases. Sedimentation and decanting are easily accomplished with simple equipment. In many cases, the separation must be aided by mechanical means, particularly filtration or centrifugation. Flotation is used to bring suspended organic matter or finely divided particles to the surface of a suspension. In the process of dissolved air flotation (DAF), air is dissolved in the suspending medium under pressure and comes out of solution when... 

The characteristic of a micro-homogeneous mixture is that its constituents cannot be separated by mechanical methods, such as sedimentation or filtration. In the nomenclature of physical chemistry, a true solution is monophasic, all its constituents being present as part of the same physical state, or phase. 

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