The Selection of Solid-Liquid Separation Processes Based on the Granulometric Characteristics of Urban Snowmelt Particulate Matter

The study of filtration and thickening of particulate systems are used in many industrial processes involving processes of solid-liquid separation, such as in sedimentation ponds, filters, the drilling of oil wells, among others. This paper aims to advance the empirical mechanisms involved in the processes of solid-liquid separation and obtain constitutive equations relating the pressure in solids and porous media permeability from non-Newtonian fluids. In the experiments used aqueous solutions of xanthan gum concentration of 0.1% in weight basis in order to ensure non-newtonian means. For the preparation of suspensions, was used calcium carbonate as particulate material in the separation process involved an initial concentration of 12% by volume. The concentrated sediment was maintained between 30 and 48% by volume. Settling tests were carried to term and sediments resulting from each test were evaluated by making use of the Gamma Rays Attenuation Technique (GRAT). The results show that GRAT is effective in determining sediment concentration distributions formed from non-Newtonian solutions, allowing the constitutive equations to obtain pressure and the solid porous medium permeability, very important for simulations of solid-liquid separation processes.

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Solid-liquid separation processes

Crystallization Process Systems ◽

10.1016/b978-075065520-0/50005-5 ◽

2002 ◽

pp. 80-122

Author(s):

A.G. Jones

Keyword(s):

Liquid Separation ◽

Separation Processes ◽

Solid Liquid ◽

Solid Liquid Separation

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Papers Presented at International Workshop on Membranes and Solid-Liquid Separation Processes

Desalination ◽

10.1016/s0011-9164(08)00429-3 ◽

2008 ◽

Vol 231 (1-3) ◽

pp. 243

Keyword(s):

International Workshop ◽

Liquid Separation ◽

Separation Processes ◽

Solid Liquid ◽

Solid Liquid Separation

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From colloidal dispersions to colloidal pastes through solid-liquid separation processes

Pure and Applied Chemistry ◽

10.1351/pac200577081369 ◽

2005 ◽

Vol 77 (8) ◽

pp. 1369-1394 ◽

Cited By ~ 6

Author(s):

J. B. Madeline ◽

M. Meireles ◽

J. Persello ◽

C. Martin ◽

R. Botet ◽

...

Keyword(s):

Silica Nanoparticles ◽

Volume Fraction ◽

Cell Model ◽

Solid Particles ◽

Fractal Structures ◽

Particle Volume ◽

Liquid Separation ◽

Separation Processes ◽

Solid Liquid ◽

Solid Liquid Separation

Solid-liquid separation is an operation that starts with a dispersion of solid particles in a liquid and removes some of the liquid from the particles, producing a concentrated solid paste and a clean liquid phase. It is similar to thermodynamic processes where pressure is applied to a system in order to reduce its volume. In dispersions, the resistance to this osmotic compression depends on interactions between the dispersed particles.The first part of this work deals with dispersions of repelling particles, which are either silica nanoparticles or synthetic clay platelets, dispersed in aqueous solutions. In these conditions, each particle is surrounded by an ionic layer, which repels other ionic layers. This results in a structure with strong short-range order. At high particle volume fractions, the overlap of ionic layers generates large osmotic pressures; these pressures may be calculated, through the cell model, as the cost of reducing the volume of each cell. The variation of osmotic pressure with volume fraction is the equation of state of the dispersion. The second part of this work deals with dispersions of aggregated particles, which are silica nanoparticles, dispersed in water and flocculated by multivalent cations. This produces large bushy aggregates, with fractal structures that are maintained through interparticle surface-surface bonds. As the paste is submitted to osmotic pressures, small relative displacements of the aggregated particles lead to structural collapse. The final structure is made of a dense skeleton immersed in a nearly homogeneous matrix of aggregated particles. The variation of osmotic resistance with volume fraction is the compression law of the paste; it may be calculated through a numerical model that takes into account the noncentral interparticle forces. According to this model, the response of aggregated pastes to applied stress may be controlled through the manipulation of interparticle adhesion.

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