Evaluation of Consolidation Behavior by Combined Membrane Filtration and Stepped Cake Compression

Abstract

A method is proposed for determining the compression-permeability (C-P) data expressed as the dependences of the local specific cake resistance and local cake porosity on the solid compressive pressure from a combined membrane filtration and stepped cake compression test. Filtration employing a membrane with a high flow resistance, which provided the pressure dependence of the average specific cake resistance, was followed by step-up compression, which gave cake porosities at several compressive pressures. On the basis of these data collected as the time variation of the dewatering volume, the compression-permeability data of bentonite slurry were evaluated. Consolidation behaviors of the filter cake and semi-solid material were accurately described on basis of the C-P data.

A new approach for determining compressibility and permeability characteristics of dredged slurries with high water content

“…The quantity in Eq. ( 12) represents the average solidosity of the cake at the end 1 -𝜀 av,t of the filtration process and can be determined by considering the mass conservation for the whole system as follows (Iritani et al 2018):…”

“…This is in sharp contrast to other indirect methods which are based on various forms of the filtration theory with the inputs of cumbersome local measurements of the cake porosity (Lu et al 1998b;Sedin et al 2003) and of the liquid pressure profile across the cake (Lu et al 1998c). Recently, Iritani et al (2018) combined a method based on instantaneous filtration with the stepped cake compression so as to simultaneously evaluate the permeability and the compressibility.…”

“…Accordingly, in this paper, the filtration stage is utilized for determining the compressibility and permeability of dredged slurries by using the filtration theory of compressible cake from the chemistry discipline. To be specific, the combined filtration and compression method, as proposed by Iritani et al (2018), is addressed herein because it is time efficient and has easy data acquisition. The more complete continuity-based filtration theory is not adopted since the governing equations are highly nonlinear, which necessitates a complex search optimization algorithm (Tien, 2012) for determining the constitutive parameters through fitting the theory predictions into the test data.…”

An Axi-Symmetric Problem of Suspensions Filtering with the Formation of a Cake Layer

“…The separation of the suspension in which solid particles are suspended is carried out using a filter. Suspension separation processes are found in chemical, petrochemical, oil refining, coal, food, and other industries [1][2][3][4][5][6][7][8][9][10][11].…”

“…The properties of the cake are characterized by several parameters [1,3,7,8,12]: the volume fraction of the particle, the solidosity (particle volume fraction) ε s , or the cake permeability k. These parameters are assumed to only be functions of the cake compressive stress p s…”