Low energy ballasted flotation

Date published

2009-08-01T00:00:00Z

Free to read from

Supervisor/s

Journal Title

Journal ISSN

Volume Title

Publisher

Elsevier Science B.V., Amsterdam.

Department

Type

Article

ISSN

0043-1354

Format

Citation

P. Jarvis, P. Buckingham, B. Holden, B. Jefferson, Low energy ballasted flotation, Water Research, Volume 43, Issue 14, August 2009, Pages 3427-3434

Abstract

A novel process which involves the replacement or supplementation of bubbles in the dissolved air flotation process with low density beads is presented. The work comprised a series of bench-scale flotation trials treating three commonly encountered algal species (Microcystis, Melosira and Chlorella) that were removed in a flotation cell configured as either: conventional dissolved air flotation (DAF); ballasted flotation using low density 70 μm glass beads with a density of 100 kg m−3; or a hybrid process of ballasted flotation combined with conventional DAF. Results indicated that the bead only system was capable of achieving better residual turbidity than standard DAF at bead concentrations of 500 mg L−1. Addition of beads in combination with standard DAF reduced turbidity further to even lower residual turbidity levels. Algae removal was improved when glass beads were dosed, but removal was dependent on algal species. Microcystis was removed by 97% for bead only systems and this removal did not change significantly with the addition of air bubbles. Melosira was the next best removed algae with bead only dosed systems giving similar removals to that achieved by standard DAF using a 10% air recycle ratio (81 and 76% removal respectively). Chlorella was the least well removed algae by bead only systems (63% removal). However, removal was rapidly improved to 86% by the addition of air bubbles using only a 2% recycle ratio. Energy estimations suggested that at least a 50% energy reduction could be achieved using the process offering a potential route for future development of low energy separation processes for algae rem

Description

Software Description

Software Language

Github

Keywords

Algae, Bubbleless, Dissolved air flotation, Energy

DOI

Rights

Relationships

Relationships

Supplements

Funder/s