A bioflocculant-supported dissolved air flotation system for the removal of suspended solids, lipids and protein matter from poultry slaughterhouse wastewater

2018 ◽  
Vol 78 (2) ◽  
pp. 452-458 ◽  
Author(s):  
C. Dlangamandla ◽  
S. K. O. Ntwampe ◽  
M. Basitere
Keyword(s):  
Steady State ◽  
Suspended Solids ◽  
Total Suspended Solids ◽  
Bacillus Sp ◽  
Dissolved Air Flotation ◽  
Slaughterhouse Wastewater ◽  
Air Flotation ◽  
Dissolved Air

Abstract In this study, two previously identified isolates, i.e. Comamonas aquatica (BF-3) and Bacillus sp. BF-2, were determined to be suitable candidates to utilise in a bioflocculant-supported dissolved air flotation (Bio-DAF) system as a pretreatment system for poultry slaughterhouse wastewater (PSW). A 2% (v/v) (bioflocculant:PSW) strategy was used for the DAF to reduce total suspended solids (TSS), lipids and proteins in the PSW, by supplementing the bioflocculants produced and the co-culture (C. aquatica BF-3 and Bacillus sp. BF-2) directly into the DAF. The Bio-DAF was able to reduce 91% TSS, 79% proteins and 93% lipids when the DAF system was operating at steady state, in comparison with a chemical DAF operated using 2% (v/v) alum that was able to only reduce 84% TSS, 71% proteins and 92% lipids. It was concluded that the Bio-DAF system worked efficiently for the removal of suspended solids, lipids and proteins, achieving better results than when alum was used.

Oil Removal from Refinery Wastes by Air Flotation

1974 ◽  
Vol 9 (1) ◽  
pp. 328-339 ◽  
Author(s):  
B. Volesky ◽  
S. Agathos
Keyword(s):  
Suspended Solids ◽  
Suspended Solid ◽  
Oil Removal ◽  
Dissolved Air Flotation ◽  
Physical Separation ◽  
Sedimentation Technique ◽  
Flocculation Aid ◽  
Flotation Technique ◽  
Air Flotation ◽  
Dissolved Air

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.

scholarly journals Simulation and control of dissolved air flotation and column froth flotation with simultaneous sedimentation

2020 ◽  
Vol 81 (8) ◽  
pp. 1723-1732 ◽  
Author(s):  
Raimund Bürger ◽  
Stefan Diehl ◽  
María Carmen Martí ◽  
Yolanda Vásquez
Keyword(s):  
Wastewater Treatment ◽  
Steady State ◽  
Froth Flotation ◽  
Operating Conditions ◽  
Dynamic Simulations ◽  
Dissolved Air Flotation ◽  
One Dimensional ◽  
Drift Flux ◽  
Air Flotation ◽  
Dissolved Air

Abstract Flotation is a separation process where particles or droplets are removed from a suspension with the aid of floating gas bubbles. Applications include dissolved air flotation (DAF) in industrial wastewater treatment and column froth flotation (CFF) in wastewater treatment and mineral processing. One-dimensional models of flotation have been limited to steady-state situations for half a century by means of the drift-flux theory. A newly developed dynamic one-dimensional model formulated in terms of partial differential equations can be used to predict the process of simultaneous flotation of bubbles and sedimentation of particles that are not attached to bubbles. The governing model is a pair of first-order conservation laws for the aggregate and solids volume fractions as functions of height and time. An analysis of nonlinear ingredients of the governing equations helps to identify desired steady-state operating conditions. These can be chosen by means of operating charts, which are diagrams that visualize regions of admissible values of the volumetric flows of the feed input and underflow outlet. This is detailed for the DAF thickening process. Dynamic simulations are obtained with a recently developed numerical method. Responses to control actions are demonstrated with scenarios in CFF and DAF.

scholarly journals Bio-Delipidation of Dissolved Air Flotation Pre-Treated Poultry Slaughterhouse Wastewater

2018 ◽  
Author(s):  
Siyasanga Mbulawa ◽  
Seteno Karabo Obed Ntwampe ◽  
Moses Basitere ◽  
Yolanda Mpentshu ◽  
Cynthia Dlangamandla ◽  
...  
Keyword(s):  
Bacillus Cereus ◽  
Oxygen Demand ◽  
Industrial Applications ◽  
Quality Parameters ◽  
Bacterial Strains ◽  
Oil And Grease ◽  
Dissolved Air Flotation ◽  
Slaughterhouse Wastewater ◽  
Air Flotation ◽  
Dissolved Air

Delipidation is a method of defatting that is generally associated with the removal of residual lipids or lipid groups from matrices in which they are present in minute quantities. The bio-delipidation of protein-rich poultry slaughterhouse wastewater (PSW) pre-treated with a dissolved air flotation (DAF) system was developed using microbial lipases from bacterial strains isolated from the PSW. The efficacy of the bio-delipidation system was quantitatively characterised by comparing the quality parameters i.e., fats, oil and grease (FOGs), turbidity, total suspended solutes (TSS), total chemical oxygen demand (tCOD) and protein concentration of the DAF pre-treated PSW and bio-lipidized samples. As hypothesised, the bio-delipidation system was able to effectively reduce the levels of these quality parameters when crude lipases of Bacillus cereus AB1 (BF3) and Bacillus cereus CC-1 (B30) strains were used. Strain-dependent quality characteristics were also observed in bio-delipidized samples. The study successfully managed to complement physical reduction techniques (DAF) with biological strategies (bio-delipidation) for improved PSW quality, with potential industrial applications.

Plywood Mill Water System Closure by Dissolved Air Flotation Treatment

1999 ◽  
Vol 40 (11-12) ◽  
pp. 33-41 ◽  
Author(s):  
P. Jokela ◽  
P. Keskitalo
Keyword(s):  
Heat Recovery ◽  
Occupational Safety ◽  
Suspended Solids ◽  
Water System ◽  
Raw Material ◽  
Surface Load ◽  
Dissolved Air Flotation ◽  
Treated Water ◽  
Air Flotation ◽  
Dissolved Air

In plywood industry water is mainly needed for soaking the logs. Dissolved air flotation with chemical precipitation was found to be a suitable treatment method for the soaking basin overflow of a plywood mill using birch as raw material. According to pilot treatment studies over 90% reductions of the suspended solids are possible with a hydraulic surface load of 6.5 m3/(m2h). In subsequent experience in full scale following reductions have been achieved: suspended solids 93%, BOD7 50%, CODCr 57%, P 92% and N 52%. Two-thirds of the flotation treated water is led to flue gas scrubbers and circulated back to the soaking basin. Optionally water can be led to the heat recovery, too. One-third of the flotation treated water is disposed of as the mill effluent. Concentrations of organic matter in the system have been reduced after the addition of flotation indicating the possibility of further closure. However, due to the use of aluminium sulphate in coagulation, aeration is needed for sulphate reduction prevention. Further closure of the water system is possible in the future if the heat recovery is renovated, preventing the increase of the water temperature (now 37°C) which otherwise might cause occupational safety hazards.

Dissolved air flotation clarification of activated sludge and wastewaters from chemical industry

2003 ◽  
Vol 47 (1) ◽  
pp. 205-210 ◽  
Author(s):  
P. Jokela ◽  
J. Immonen
Keyword(s):  
Activated Sludge ◽  
Suspended Solids ◽  
Animal Feed ◽  
Paper Industry ◽  
Dissolved Air Flotation ◽  
Jar Test ◽  
Air Flotation ◽  
Carry Over ◽  
Winter Time ◽  
Dissolved Air

Wastewaters from separate chemical factories are treated together in an extended aeration activated sludge plant. The factories produce chemicals for paper industry (e.g. starch), latexes and animal feed. The components of the wastewaters include styrene, tertiary butanol and vinyl acetate. Activated sludge is clarified by sedimentation. During winter time, when the water temperature was 3-12°C, the clarification deteriorated causing carry over of suspended solids containing COD. Enhancement of suspended solids and COD removals was studied in a dissolved air flotation jar test unit. Flotation trials were conducted for activated sludge, sedimentation treated final effluent (tertiary treatment) and separate wastewater fractions. The need for chemicals, flocculation and amount of recycle water were judged according to the achieved removals. Dissolved air flotation was found well suited for the clarification of activated sludge, but not technically and economically feasible for the clarification of the wastewater streams before the activated sludge treatment.

Optimization of Fenton's reagent coupled to Dissolved Air Flotation to remove cyanobacterial odorous metabolites and suspended solids from raw surface water

2011 ◽  
Vol 64 (8) ◽  
pp. 1668-1674 ◽  
Author(s):  
Jorge A. Elías-Maxil ◽  
Fotis Rigas ◽  
María Teresa Orta de Velásquez ◽  
Rosa-María Ramírez-Zamora
Keyword(s):  
Water Treatment ◽  
Suspended Solids ◽  
Advanced Oxidation Process ◽  
Treatment Plant ◽  
Drinking Water Treatment ◽  
Fenton’S Reagent ◽  
Fenton's Reagent ◽  
Dissolved Air Flotation ◽  
Air Flotation ◽  
Dissolved Air

Ferrous salts are commonly used as coagulants in Water Treatment Plants (WTPs). When these salts are combined with hydrogen peroxide in acidic conditions – besides coagulation – an additional Advanced Oxidation Process (Fenton's reagent) can take place. Using a response surface methodology, this paper presents the optimization of a novel treatment system constituted by Fenton's reagent (FE) and Dissolved Air Flotation (DAF) for removing 2-Methylisoborneol (MIB), geosmin and Total Suspended Solids (TSS) from raw water. FE was proven able to remove completely both micro pollutants found in the influent of a drinking water treatment plant. Moreover, higher clarification rate was achieved by coupling FE-DAF with respect FE-Sedimentation.

Removal of hydrocarbons from petrochemical wastewater by dissolved air flotation

2001 ◽  
Vol 43 (8) ◽  
pp. 107-113 ◽  
Author(s):  
N. I. Galil ◽  
D. Wolf
Keyword(s):  
Organic Matter ◽  
Biological Treatment ◽  
Suspended Solids ◽  
Cationic Polyelectrolyte ◽  
Free Form ◽  
Dissolved Air Flotation ◽  
Separation Unit ◽  
Hydrophobic Compounds ◽  
Air Flotation ◽  
Dissolved Air

The dissolved air flotation (DAF) method has an important role in the removal of hydrocarbons, as well as in the protection of the biological treatment, which usually follows the DAF. The aims of this study were to evaluate the removal efficiencies of suspended solids, general organic matter, hydrocarbons and phenols by DAF, as influenced by the flocculant type, aluminum sulfate (alum) or a cationic polyelectrolyte. Laboratory batch experiments included chemical flocculation followed by DAF, controlling the flocculant dose and the air to solids ratio. The characterization of the influent and effluent was based on general analysis of organic matter (COD), suspended solids, hydrocarbons and phenols. The influent to all experiments was supplied daily from the outlet of a full scale oil-water gravitational separation unit at a petrochemical complex in Haifa, Israel. The influent contained hydrocarbons in the range of 20 to 77 mg/L. Usually less than 10% were found in “free” form, 70 to 80% were emulsified and 10 to 20% were dissolved. The DAF process enabled us to reduce the general hydrocarbon content by 50 to 90%. The effluent was characterized by stable and uniform levels of suspended solids, and oil, almost without depending on the influent concentrations. The results indicate that the chemical flocculation followed by DAF removed efficiently the emulsified phase, which could be aggregated and separated to the surface. However, it was found that the process could also remove substantial amounts of dissolved organic matter. This mechanism could be explained by the hydrophobic characteristics of some of the substances, which could bind to the solid surfaces. It was found that aggregates created by the flocculation with the cationic polyelectrolite (C-577) could remove up to 40% from the dissolved hydrocarbon. Alum flocs also indicated removal of soluble materials, mainly phenols. The results obtained in this study indicated the possibility to improve the protection of the biological treatment process by preliminary removal of hydrophobic compounds, usually considered as either inhibitory or toxic. This removal can be based on sorption onto aggregates created by chemical flocculation, which can be efficiently removed by dissolved air flotation.

Sign in / Sign up

Export Citation Format

Share Document