Degradation of chlorophenols by biofilms on semi-permeable membranes in two types of fixed bed reactors

1995 ◽  
Vol 32 (8) ◽  
pp. 205-212 ◽  
Author(s):  
A. Wobus ◽  
S. Ulrich ◽  
I. Röske
Keyword(s):  
Continuous Flow ◽  
Plug Flow ◽  
Fixed Bed ◽  
Biofilm Reactor ◽  
Flow Conditions ◽  
Concentration Gradients ◽  
Batch Mode ◽  
Sequencing Batch Biofilm Reactor ◽  
Fixed Bed Reactors ◽  
Protozoan Community

Two identical fixed bed reactors containing gas-permeable tubings as carrier material were compared for the elimination of chlorophenols. Under plug flow conditions, the continuous flow operation resulted in a stratification of biomass due to concentration gradients. To achieve a homogeneous colonization, the sequencing batch mode has been applicated to one biofilm reactor (Sequencing Batch Biofilm Reactor - SBBR). Concentration gradients after filling, probably due to sorption phenomena, caused an uneven distribution of biomass in the SBBR. However, the colonization of the SBBR was more homogeneous as compared to the continuously operated reactor (CFBR). As to the elimination of a trichlorophenol (2,4,5-trichlorophenol - TCP), no significant differences between the SBBR and the CFBR were observed with regard to its sensitivity against load surges. It is to be supposed that sorption to the biofilm was included in the elimination of chlorophenols. A higher diversity of protozoan community and meiofauna is obviously to be attributed to continuous flow.

Elimination of p-chlorophenol in biofilm reactors - a comparative study of continuous flow and sequenced batch operation

1995 ◽  
Vol 31 (1) ◽  
pp. 51-60 ◽  
Author(s):  
Hans-Peter Kaballo ◽  
Yuangang Zhao ◽  
Peter A. Wilderer
Keyword(s):  
Continuous Flow ◽  
Fixed Bed ◽  
Experimental Studies ◽  
Biofilm Reactor ◽  
Sorption Properties ◽  
Batch Mode ◽  
Biofilm Reactors ◽  
Sequencing Batch Biofilm Reactor ◽  
High Flexibility ◽  
Better Than

The chlorophenol elimination potential of two identically designed fixed bed biofilm reactors was compared. One of the reactors was operated continuously, and the other in sequenced batch mode. In the continuous flow biofilm reactor (CFBR) a stratification of biomass occurred, whereas biomass in the sequencing batch biofilm reactor (SBBR) developed uniformly due to the use of an advanced fill strategy. Recirculation was needed to overcome biosorption during filling and to achieve equal biomass distribution. Under shock loading, degradation in SBBR was better than in CFBR. However, even the CFBR showed a high flexibility, i.e. it performed better than expected. Sorption properties in both reactors seem to be responsible for the flexibility in terms of break through. Experimental studies and modelling of sorption properties are necessary to describe the response of biofilm reactors to unsteady state conditions.

Metal–organic frameworks for the removal of the emerging contaminant atenolol under real conditions

2021 ◽  
Vol 50 (7) ◽  
pp. 2493-2500
Author(s):  
Sara Rojas ◽  
Jorge A. R. Navarro ◽  
Patricia Horcajada
Keyword(s):  
Continuous Flow ◽  
Metal Organic Frameworks ◽  
Fixed Bed ◽  
Emerging Contaminant ◽  
Flow Conditions ◽  
Metal Organic ◽  
Fixed Bed System

A defective Metal-Organic Frameworks as an improved material for the construction of a fixed-bed system working under continuous flow conditions for the removal of the emerging contaminant atenolol.

A new device to select carriers for biomass immobilization and application in an aerobic/anaerobic fixed-bed sequencing batch biofilm reactor for nitrogen removal

2016 ◽  
Vol 74 (11) ◽  
pp. 2666-2674 ◽  
Author(s):  
A. Sarti ◽  
A. W. Lamon ◽  
A. Ono ◽  
E. Foresti
Keyword(s):  
Nitrogen Removal ◽  
Fixed Bed ◽  
Ammonia Concentration ◽  
Nitrogen Loading ◽  
Biofilm Reactor ◽  
New Approach ◽  
New Device ◽  
Sequencing Batch Biofilm Reactor ◽  
Biofilm Carrier ◽  
Aerobic And Anaerobic

This study proposes a new approach to selecting a biofilm carrier for immobilization using dissolved oxygen (DO) microsensors to measure the thickness of aerobic and anaerobic layers in biofilm. The biofilm carriers tested were polyurethane foam, mineral coal (MC), basaltic gravel, and low-density polyethylene. Development of layers in the biofilm carrier surface was evaluated using a flow cell device, and DO profiles were conducted to determine the size of the layers (aerobic and anaerobic). MC was the biofilm carrier selected due to allowing the development of larger aerobic and anaerobic layers in the biofilm (896 and 1,058 μm, respectively). This ability is supposed to improve simultaneous nitrogen removal by nitrification and denitrification biological processes. Thus, as a biofilm carrier, MC was used in a fixed-bed sequencing batch biofilm reactor (FB-SBBR) for treatment of wastewater with a high ammonia concentration (100–400 mgNH4+-N L−1). The FB-SBBR (15.0 L) was filled with matrices of the carrier and operated under alternating aeration and non-aeration periods of 6 h each. At a mean nitrogen loading rate of 0.55 ± 0.10 kgNH4+-N m−3 d−1, the reactor attained a mean nitrification efficiency of 95 ± 9% with nitrite as the main product (aerobic period). Mean denitrification efficiency during the anoxic period was 72 ± 13%.

scholarly journals Facile Oxidations under Flow Conditions in Fixed-Bed Reactors

Synfacts ◽  
2010 ◽  
Vol 2010 (11) ◽  
pp. 1313-1313 ◽  
Author(s):  
A. Kirschning ◽  
J. Wegner ◽  
S. Ceylan ◽  
C. Friese
Keyword(s):  
Fixed Bed ◽  
Flow Conditions ◽  
Fixed Bed Reactors

Biological treatment of leachates from hazardous waste landfills using SBBR technology

1996 ◽  
Vol 34 (7-8) ◽  
pp. 437-444 ◽  
Author(s):  
J. Dollerer ◽  
P. A. Wilderer
Keyword(s):  
Hazardous Waste ◽  
Removal Rate ◽  
Fixed Bed ◽  
Biofilm Reactor ◽  
Fixed Bed Reactor ◽  
Bulk Liquid ◽  
Sequencing Batch Biofilm Reactor ◽  
Aeration System ◽  
Volatile Organic ◽  
Hazardous Waste Landfills

Bench-scale experiments with two different types of fixed bed reactor have been conducted in order to investigate the potential of SBBr technology (Sequencing Batch Biofilm Reactor) for treatment of leachates from different hazardous waste landfills. Reactor A was equipped with a membrane oxygenatition system for bubble free transfer of oxygen into the bulk liquid. In constract, reactor B was bubble aerated. The process was found to be remarkably stable. An average DOC removal rate of 68% was achieved with a 12-hour cycle. The emission of biodegradable volatile organic substances was observed to be significantly reduced by using bubble free aeration system.

scholarly journals Optimization of Streptococcus agalactiae Biofilm Culture in a Continuous Flow System for Photoinactivation Studies

Pathogens ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 1212
Author(s):  
Michal K. Pieranski ◽  
Michal Rychlowski ◽  
Mariusz Grinholc
Keyword(s):  
Streptococcus Agalactiae ◽  
Continuous Flow ◽  
Human Keratinocytes ◽  
Culture Conditions ◽  
Biofilm Reactor ◽  
Vaginal Fluid ◽  
Flow Conditions ◽  
Biofilm Growth ◽  
Microtiter Plates ◽  
Biofilm Production

Streptococcus agalactiae is a relevant cause of neonatal mortality. It can be transferred to infants via the vaginal tract and cause meningitis, pneumonia, arthritis, or sepsis, among other diseases. The cause of therapy ineffectiveness and infection recurrence is the growth of bacteria as biofilms. To date, several research teams have attempted to find a suitable medium for the cultivation of S. agalactiae biofilms. Among others, simulated vaginal fluid has been used; however, biofilm production in this medium has been found to be lower than that in tryptic soy broth. We have previously shown that S. agalactiae can be successfully eradicated by photoinactivation in planktonic culture, but there have been no studies on biofilms. The aim of this study was to optimize S. agalactiae biofilm culture conditions to be used in photoinactivation studies. We compared biofilm production by four strains representing the most common serotypes in four different broth media with crystal violet staining. Then, we evaluated stationary biofilm culture in microtiter plates and biofilm growth in a CDC Biofilm Reactor® (BioSurface Technologies, Bozeman, MT, USA) under continuous flow conditions. Subsequently, we applied Rose Bengal-mediated photoinactivation to both biofilm models. We have shown that photoinactivation is efficient in biofilm eradication and is not cyto/phototoxic to human keratinocytes. We found conditions allowing for stable and repetitive S. agalactiae biofilm growth in continuous flow conditions, which can be successfully utilized in photoinactivation assays and potentially in all other antibacterial studies.

Application of biofiltration in the crude oil processing industry

1999 ◽  
Vol 39 (8) ◽  
pp. 71-76 ◽  
Author(s):  
I. Sekoulov ◽  
S. Brinke-Seiferth
Keyword(s):  
Crude Oil ◽  
Plug Flow ◽  
Fixed Bed ◽  
Treatment Plant ◽  
Flow Conditions ◽  
Industrial Waste Water ◽  
Power Requirement ◽  
Processing Industry ◽  
Oil Processing ◽  
Treatment Stage

For the purification of industrial waste water from the crude oil processing industry, a multiple stage treatment plant is recommended. Biofiltration takes place as a secondary treatment stage. Under plug-flow conditions residual compounds can be treated efficiently with a reduced power requirement. Specialized microorganisms, utilizing compounds which are not readily biodegradable, are immobilized on burned clay. Usually toxic peaks do not inhibit the microorganisms in the biofilm. This depends on the short retention time of the water in fixed bed systems and on the characteristic of the biofilm. Dissolved, colloidal or particulate non-biodegradable substances will be adsorbed on the biofilm and can be removed by backwashing the reactor. A description of the treatment plants at BP-oiltech Hamburg and Shell Refinery Hamburg is given. The design of the fixed film reactors is discussed.

Sign in / Sign up

Export Citation Format

Share Document