Failure Analysis of a Dissolved Air Flotation Treatment Plant in a Dairy Industry

2011 ◽  
Vol 11 (2) ◽  
pp. 110-122 ◽  
Author(s):  
J. O. Babatola ◽  
K. T. Oladepo ◽  
S. Lukman ◽  
N. O. Olarinoye ◽  
I. A. Oke
Keyword(s):  
Failure Analysis ◽  
Dairy Industry ◽  
Treatment Plant ◽  
Dissolved Air Flotation ◽  
Flotation Treatment ◽  
Air Flotation ◽  
Dissolved Air

Optimising dissolved air flotation/filtration treatment of algae-laden lagoon effluent using surface charge: a Bolivar treatment plant case study

2012 ◽  
Vol 66 (8) ◽  
pp. 1684-1690 ◽  
Author(s):  
Russell Yap ◽  
Michael Holmes ◽  
William Peirson ◽  
Michael Whittaker ◽  
Richard Stuetz ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Surface Charge ◽  
Wastewater Treatment Plant ◽  
Pilot Plant ◽  
Treatment Plant ◽  
Dissolved Air Flotation ◽  
Air Flotation ◽  
A Charge ◽  
Dissolved Air

Dissolved air flotation (DAF) incorporating filtration (DAFF) is used at the Bolivar wastewater treatment plant (WWTP) to polish lagoon effluent for reuse. Elevated algal populations are frequently experienced and can lead to increased coagulant requirements and process control issues. Streaming current detectors (SCDs) and a charge demand analyser (CDA) were used to monitor the full-scale plant. This was followed by an optimisation study using a pilot plant with a CDA. It was found that the normal operational charge demand range for DAF at Bolivar was between −46 and −40 μeq L−1. Decreasing the pH of coagulation reduced coagulant consumption and facilitated more sensitive CDA responses to changes in alum dose.

Principles and applications of dissolved air flotation

1995 ◽  
Vol 31 (3-4) ◽  
pp. 1-23 ◽  
Author(s):  
James K. Edzwald
Keyword(s):  
Bubble Formation ◽  
Treatment Plant ◽  
Drinking Water Treatment ◽  
Plant Design ◽  
Dissolved Air Flotation ◽  
Floc Size ◽  
Hydrophobic Particles ◽  
Air Flotation ◽  
The Impact ◽  
Dissolved Air

Principles of dissolved air flotation (DAF) discussed include: bubble formation and size, bubble-particle interactions, measures of supplied air, and modeling of the reaction and clarification zones of the flotation tank. Favorable flotation conditions for bubble attachment or adhesion to particles requires a reduction in the charge of particles and production of hydrophobic particles or hydrophobic spots on particle surfaces. A conceptual model for the bubble-particle reaction zone based on the single collector collision efficiency is summarized and discussed. An alternative modeling approach is considered. Clarification or separation zone modeling is based on particle-bubble agglomerate rise velocities. The application of DAF in drinking water treatment is addressed beginning with summaries of design and operating parameters for several countries. DAF should not be considered as a separate process, but integrated into the design and operation of the overall treatment plant. This concept shows that flocculation ahead of DAF has different requirements regarding floc size and strength compared to sedimentation. The efficiency of DAF in removing particles and reducing particle loads to filters needs to be integrated into DAF plant design. The impact on filtration performance is illustrated. Finally, fundamental and applied research needs are addressed.

scholarly journals Intensification Dissolved Air Flotation Treatment of Oil-Containing Wastewater

2015 ◽  
Vol 9 (5) ◽  
Author(s):  
Anton Andreevich Eskin ◽  
Gennady Aleksandrovich Zakharov ◽  
Nadezhda Sergeevna Tkach ◽  
Ksenia Vasilievna Tsygankova
Keyword(s):  
Dissolved Air Flotation ◽  
Flotation Treatment ◽  
Air Flotation ◽  
Dissolved Air

Influence of flocculation conditions in the performance of an experimental domestic sewage treatment plant consisting of an anaerobic expanded bed reactor followed by dissolved air flotation

2003 ◽  
Vol 48 (6) ◽  
pp. 285-293
Author(s):  
R.G. Penetra ◽  
M.A.P. Reali ◽  
J.R. Campos
Keyword(s):  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Domestic Sewage ◽  
Expanded Bed ◽  
Mean Velocity ◽  
Dissolved Air Flotation ◽  
Anaerobic Reactor ◽  
Air Flotation ◽  
Dissolved Air

This paper presents the results of a study performed with an experimental domestic sewage treatment plant (240 m3.d-1 flow) consisting of expanded bed anaerobic reactor (EBAR) followed by dissolved air flotation (DAF) unit. For the flotation step, the anaerobic reactor effluent was previously coagulated with 50 mgFeCl3.l-1 and flocculated under different conditions (mean velocity gradient, Gf, and flocculation time, Tf). The Gf values were from 60 to 100 s-1 associated with 13 and 20 min Tf values. During the tests, the following operational conditions of the flotation unit were maintained: chemical addition (50 mgFeCl3.l-1), 18% recirculation rate associated with a pressure of 450 ± 10 kPa in the saturation chamber and overflow rate of 180 m3.mÐ2.d-1. Temperature ranged from 23.8¡C to 30.01/4C. Best results were achieved for Gf = 80 s-1 and Tf = 20 min. For these conditions, the DAF unit removal efficiencies were: 94.4% for chemical oxygen demand (with 53 mg.l-1 COD residual), 87% for phosphorus (with 0.80 mgP.l-1 residual), 96.7% for total suspended solids (with 9 mg.l-1 TSS residual) and 96.4% for turbidity (with 12.9 NTU residual), when the anaerobic reactor effluents have worst quality during the whole day.

Comparison of dissolved air flotation and direct filtration

1995 ◽  
Vol 31 (3-4) ◽  
pp. 113-124 ◽  
Author(s):  
C. Ferguson ◽  
G. S. Logsdon ◽  
D. Curley
Keyword(s):  
South Carolina ◽  
Reservoir Water ◽  
Dissolved Air Flotation ◽  
Direct Filtration ◽  
Flotation Treatment ◽  
Treatment Train ◽  
Air Flotation ◽  
And Control ◽  
Iron And Manganese ◽  
Dissolved Air

Direct filtration with and without pre-ozone, and dissolved air flotation and filtration were evaluated for clarification of high quality reservoir water in Greenville, South Carolina, USA. Goals of the study included production of low turbidity filtered water and control of algae, iron and manganese, and disinfection by-product precursors. The dissolved air flotation treatment train gave much longer filter runs than direct filtration, when both processes met the 0.10 NTU goal for filtered water quality. Use of pre-ozone was beneficial for direct filtration. Removal of TOC, DBP precursors, and iron and manganese were similar for both processes.

Dissolved air flotation treatment of concentrated fish farming wastewaters

2001 ◽  
Vol 43 (8) ◽  
pp. 115-121 ◽  
Author(s):  
P. Jokela ◽  
E. Ihalainen ◽  
J. Heinänen ◽  
M. Viitasaari
Keyword(s):  
Wastewater Treatment ◽  
Fish Farming ◽  
Chemical Precipitation ◽  
Subsequent Treatment ◽  
Dissolved Air Flotation ◽  
Pilot Trials ◽  
Flotation Treatment ◽  
Air Flotation ◽  
Solids Removal ◽  
Dissolved Air

Fish farming wastewaters contain nutrients, phosphorus and nitrogen, which promote eutrophication in the typically shallow farming sites in Finland. Fish farming wastewater treatment is problematic because of large quantities of very dilute wastewater (200 – 600 m3/kg fish produced). In practice wastewater treatment is concentrated on suspended solids removal. Treatment can be done in two steps: concentration of the very dilute wastewater and subsequent treatment of the concentrated wastewater. Dissolved air flotation pilot trials were conducted using two types of concentrated wastewaters: settled solids from a sludge hopper of a cultivation basin and swirl separator concentrate. Two different pilot plants were used and performances compared. Both mechanical treatment and precipitation by ferric salts were applied. Depending on the influent quality, 70 to 90% phosphorus reductions were achieved without chemicals. Chemical precipitation and flotation produced 90% phosphorus reductions and effluent concentrations at the level of 0.05 mgP/l when 13 m3/(m2h) hydraulic loading was used.

Sign in / Sign up

Export Citation Format

Share Document