Validation of a new filtration technique for dewaterability characterization

Abstract

Characterization of the compressibility and permeability of flocculated suspensions is Traditional pressure filtration experiments involve the pressure filtration of a particulate suspension in which the time of filtration t is monitored as a function of piston height from which the specific volume of filtrate V is determined. P,.($) is determinedfiom the equilibrium solids volume fraction. The gradient d(t/V)/dV is traditionally used to determine R($) using a suspension filtration theory developed by Landman and

Modeling of the Consolidation Stage in Pressure Filtration of Compressible Cakes

“…Recently, Usher et al (17) and deKretser et al (18) have proposed a stepped pressure filtration strategy for rapid measurements of the dewatering parameters, which should be highly convenient for model-based design and scale up studies. This quick and absolute method is ordinarily feasible only in an offsite laboratory environment.…”

Reply to Letter to the Editor

“…2,3 The aim of our work was not to invalidate or disparage the volume-averaged Darcian approach, but rather to investigate the material properties and operating conditions required for nontraditional behavior. It has been shown in other articles [4][5][6][7] that the parameters used by the local and volume-averaged approaches are related, such that the conclusions made in Stickland et al, 2005 1 , also apply to the volume-averaged approach. It is our intention to bridge the divide in this area rather than deepen it, and our article, although not attempting to discuss this issue, further highlights the inadequacy of both approaches for some industrial realities.…”

Dewatering behaviour of water treatment sludges associated with contaminated site remediation in Antarctica

“…For all experiments the coagulant used was FeCl 3 at a dose of approximately 20 mg L −1 . The dewaterability of the various sludges was determined by a combination of batch settling tests and stepped pressure filtration Usher et al, 2001;Usher, 2002).…”