skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Dissolved Air Flotation for Rapid Dewatering and Separation of Legacy Sludge Wastes - 19065

Conference ·
OSTI ID:23002895
; ; ; ;  [1];  [2]; ;  [3]
  1. School of Chemical and Process Engineering, University of Leeds (United Kingdom)
  2. School of Earth and Environment, University of Leeds (United Kingdom)
  3. Sellafield Ltd (United Kingdom)

As a low footprint, high efficiency separation process, Dissolved Air Floatation (DAF) could effectively be retrofitted into existing waste management facilities at nuclear sites such Sellafield and Hanford to rapidly separate particulates from aqueous suspensions. The simplicity (no moving parts) and size of this technology coupled with low cost of construction and reagent purchase would also be ideal for ease of facility decommissioning with minimum impact to secondary waste generation. For this study, methyl isobutyl carbinol (MIBC) was used in this research as a frothing agent to produce a preferable stable foam. Mg(OH){sub 2} was selected as a test material as it is the result of long term corrosion of Magnox fuel in UK nuclear fuel storage ponds. Due to the cationic nature of the Mg(OH){sub 2} test material, the anionic surfactant, Sodium Dodecyl Sulphate (SDS) was used as collector to modify the surface properties to increase hydrophobicity. The performance of anionic SDS in floating 2.5%v/v Mg(OH){sub 2} was compared to the adsorption isotherm of SDS on Mg(OH){sub 2} to determine monolayer coverage surfactant dose which was investigated using Total Organic Carbon (TOC). SDS was found to increase particulate recovery to 93% with some water carry-over observed and it was found that particle bubble attachment was optimum for a select particle size distribution. This study proved that potential application of flotation as an efficient viable dewatering technique for common magnesium hydroxide based legacy wastes, using cheap, readily available collector and frother agents. (authors)

Research Organization:
WM Symposia, Inc., PO Box 27646, 85285-7646 Tempe, AZ (United States)
OSTI ID:
23002895
Report Number(s):
INIS-US-21-WM-19065; TRN: US21V1010043228
Resource Relation:
Conference: WM2019: 45. Annual Waste Management Conference, Phoenix, AZ (United States), 3-7 Mar 2019; Other Information: Country of input: France; 45 refs.; available online at: https://www.xcdsystem.com/wmsym/2019/index.html
Country of Publication:
United States
Language:
English