Cost Effective Secondary Clarification of UASB Reactor Effluent with the Biothane Dissolved Air Flotation Process at a Juice Manufacturing Plant

This paper presents the results of a study performed with a lab-scale dissolved-air flotation (LSDAF) unit fed with previously coagulated effluent from a pilot scale up-flow anerobic sludge blanket (UASB) reactor treating domestic sewage. Physical operational conditions for coagulation (rapid mix) and flocculation/flotation were maintained constant. Chemical (FeCl3) dosages ranged from 30 to 110 mg.l−1. The effect of pH was also verified in the range of 5.1 to 7.6 for each dosage. Best results were achieved for 65 mg.l−1 of FeCl3 and pH values between 5.3 and 6.1. For these conditions, the removal efficiencies obtained in the LSDAF unit were: between 87% and 91% for chemical oxygen demand (COD), between 95% and 96% for total phosphate (TP), 94% for total suspended solids (TSS), between 96% and 97% for turbidity (TU), between 90% and 93% for apparent color (AC) and more than 96% for sulfide (S). For the UASB-DAF system, global efficiencies would be around 98% for COD, 98% for TP, 98.4% for TSS, 99.3% for TU and 98% for AC. The stripped gases treatment is desirable.

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Decision of Optimal Coagulant Dosage for SeDAF (Sedimentation and Dissolved Air Flotation) Process Applicable to Enhanced Phosphorus Removal

Journal of Korean Society of Water Science and Technology ◽

10.17640/kswst.2020.28.4.33 ◽

2020 ◽

Vol 28 (4) ◽

pp. 33-42

Author(s):

Yeoju Jang ◽

Jinhong Jung ◽

Hyangyoun Chang ◽

Nari Park ◽

Hyunman Lim ◽

...

Keyword(s):

Phosphorus Removal ◽

Dissolved Air Flotation ◽

Flotation Process ◽

Coagulant Dosage ◽

Air Flotation ◽

Dissolved Air

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Application of dissolved air flotation process for industrial sludge thickening: A laboratory-scale study

International Archives of Health Sciences ◽

10.4103/iahs.iahs_11_17 ◽

2017 ◽

Vol 4 (1) ◽

pp. 22 ◽

Cited By ~ 1

Author(s):

MohammadBagher Miranzadeh ◽

Ali Atamaleki ◽

Gholamreza Mostafaii ◽

Hossein Akbari ◽

Leila Iranshahi ◽

...

Keyword(s):

Laboratory Scale ◽

Industrial Sludge ◽

Dissolved Air Flotation ◽

Flotation Process ◽

Air Flotation ◽

Sludge Thickening ◽

Dissolved Air

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The feasibility of electro-osmotic belt filter dewatering technology at pilot scale

Water Science & Technology ◽

10.2166/wst.2000.0153 ◽

2000 ◽

Vol 41 (8) ◽

pp. 137-144 ◽

Cited By ~ 25

Author(s):

H. G. Snyman ◽

P. Forssman ◽

A. Kafaar ◽

M. Smollen

Keyword(s):

Applied Voltage ◽

Feed Rate ◽

Cost Effective ◽

Pilot Scale ◽

Filter Press ◽

Digested Sludge ◽

Dissolved Air Flotation ◽

Anaerobically Digested Sludge ◽

Air Flotation ◽

Dissolved Air

Sewage sludge is typically dewatered using drying beds, belt filter presses or centrifuges. Mechanical dewatering of sludge is costly in terms of capital and running costs, especially the flocculent. In an attempt to address the need for more cost-effective dewatering technologies, electro-osmotic belt filtering was developed by Smollen and Kafaar in 1995. Themechanical equipment resembles a belt filter press but the belts are stainless steel, woven belts, which act as the electrodes. In this study, thefeasibility of the technology was tested at pilot scale using wasteactivated-, anaerobically digested- and dissolved air flotation sludge. The parameters which were investigated includes the applied voltage, polyelectrolyteusage and sludge feed rate. Applied voltage of between 15 and 25 volts increased the dewatering significantly in the waste activated- and anaerobically digested sludge. Applying a voltage in dissolved air flotation sludge could not enhance the efficiency of dewatering, unless stored to de-air. The technology was found as sensitive to polyelectrolyte dosages as belt presses. The performance of the electro-osmotic belt filter was sensitive to feed rate, but performed well with non-thickened waste activated sludge (0.61% solids), resulting in cake solids above 20%.

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