Dissolved air flotation in the treatment of industrial wastewaters with a special emphasis on forest and foodstuff industries

1995 ◽  
Vol 31 (3-4) ◽  
pp. 299-313 ◽  
Author(s):  
M. Viitasaari ◽  
P. Jokela ◽  
J. Heinänen

The suspended solids separation is an essential element in almost any wastewater treatment system. If sedimentation, dissolved air flotation and filtration are compared, flotation has both the largest operational ranges concerning influent suspended solids concentration and particle size, and load bearing capacities. When considering the suitability of flotation as a wastewater treatment process, important factors are the effluent and sludge qualities, operation and costs. To get a comprehensive conception of flotation, those factors are presented and discussed. Flotation is widely used in forest industry wastewater treatment, as well as in process water recirculation. It is also proven technology in foodstuff industry wastewater treatment. Several cases from both industries are presented.

2001 ◽  
Vol 43 (8) ◽  
pp. 83-90 ◽  
Author(s):  
A. C. Pinto Filho ◽  
C. C. Brandão

A bench scale study was carried out in order to evaluate the applicability of dissolved air flotation (DAF) as an advanced treatment for effluents from three different domestic wastewater treatment processes, namely: (i) a tertiary activated sludge plant ; (ii) an upflow sludge blanket anaerobic reactor (UASB); and (iii) a high-rate stabilization pond.


2012 ◽  
Vol 66 (8) ◽  
pp. 1684-1690 ◽  
Author(s):  
Russell Yap ◽  
Michael Holmes ◽  
William Peirson ◽  
Michael Whittaker ◽  
Richard Stuetz ◽  
...  

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.


1974 ◽  
Vol 9 (1) ◽  
pp. 328-339 ◽  
Author(s):  
B. Volesky ◽  
S. Agathos

Abstract Air flotation as a physical separation process for removing oily products and suspended solid matter from refinery wastewaters achieves removal efficiencies from 65% to more than 90%. Demonstrated capacity of the process for COD and BOD removal ranges up to 90%. With addition of flotation and flocculation aid chemicals better performance is achieved. Current results are presented and critically reviewed. It appears that the pressure dissolved-air flotation system employing recycle-flow operation can produce effluent containing consistently less than 15 p.p.m. of oil and suspended solids. Its performance and capacity of handling overload situations makes it superior to the conventional flocculation-sedimentation technique. Oil removal limitations of the process and current research trends are stressed including an electro-flotation technique. Some aspects of process optimization are also discussed.


Sign in / Sign up

Export Citation Format

Share Document