scholarly journals Biological Treatment by Active Sludge with High Biomass Concentration at Laboratory Scale for Mixed Inflow of Sunflower Oil and Saccharose

Environments ◽  
2017 ◽  
Vol 4 (4) ◽  
pp. 69 ◽  
Author(s):  
Pedro Cisterna
Keyword(s):  
Sunflower Oil ◽  
Biological Treatment ◽  
Biomass Concentration ◽  
Laboratory Scale ◽  
High Biomass ◽  
Active Sludge ◽  
High Biomass Concentration

scholarly journals Mass Transfer Features of Wavy-Bottomed Cascade Photobioreactors

2021 ◽  
Vol 5 (4) ◽  
pp. 86
Author(s):  
Monica Moroni ◽  
Giorgia Sed ◽  
Agnese Cicci ◽  
Barbara Mazzarotta ◽  
Nicola Verdone ◽  
...  
Keyword(s):  
Mass Transfer ◽  
Energy Efficient ◽  
Scale Up ◽  
Biomass Concentration ◽  
Efficient Production ◽  
Light Path ◽  
High Biomass ◽  
Growth Limitation ◽  
Microalgae Biomass ◽  
High Biomass Concentration

It has been suggested that the energy-efficient production of microalgae biomass can be more easily obtained in short light path photobioreactors that can be operated at high biomass concentration. On the downside, however, high biomass concentrations also require an efficient gas exchange rate to avoid metabolic growth limitation or inhibition. A cascade photobioreactor featuring a thin liquid layer flowing down a sloping, wavy-bottomed surface can be operated at a biomass concentration that is much higher compared to most usual open-type equipment. Liquid flow, upon investigation, proved to exhibit peculiar “local recirculation” hydrodynamics, potentially conducive to the mixing of superficial and deep zones of the photobioreactor. Mass transfer coefficient represents a useful parameter to optimize the performance of a microalgal photobioreactor and its scale-up. The aim of the present article is to discuss the experimental mass transfer features of this novel type of photobioreactor and highlight expected opportunities and issues entailed by different ways of installing and operating such novel types of photobioreactors.

High rate treatment by aerobic upflow sludge blanket (AUSB) with external oxygenation

2004 ◽  
Vol 50 (8) ◽  
pp. 193-200 ◽  
Author(s):  
K.R. Sharma ◽  
J.C. Huang
Keyword(s):  
Biological Treatment ◽  
Biomass Concentration ◽  
Suspended Solid ◽  
High Rate ◽  
Flow Recirculation ◽  
Suspended Solid Concentration ◽  
Specific Oxygen Uptake Rate ◽  
Volumetric Loading ◽  
High Biomass Concentration ◽  
Very High

A 3-year study was conducted using an aerobic upflow sludge blanket (AUSB) reactor to achieve high-rate biological treatment through maintenance of a high biomass concentration (7–10 g VSS/L) together with a high oxygen flux. The AUSB reactor was not aerated directly; instead, oxygenation was provided in an external chamber with flow recirculation. The oxygenation was provided at four different ressurizations: 0, 15, 20 and 25 psig. The AUSB reactor was also pressurized to avoid the flotation of biomass. The flow recirculation rate was varied from 400% to 1,500% in order to ensure adequate oxygen supply. It was found that the AUSB system was able to handle a volumetric loading of as high as 10 kg COD/m3-day with a removal efficiency of 92%. Despite a high upflow velocity through AUSB, the effluent suspended solid concentration was mostly below 60 mg/L. The active fraction of biomass in the AUSB sludge was about 3 times higher than that of the regular activated sludge. This was indicated by a very high specific oxygen uptake rate (SOUR), up to 180-250 mg O2/g VSS-hr. The sludge yield in the entire system was only 0.09 to 0.13 g VSS/g COD removed. This was mainly caused by additional auto-oxidation of biosolids in the oxygenation chamber due to flow recirculation.

Multi-inhibition kinetic model for the growth ofAlcaligenes eutrophus

1995 ◽  
Vol 41 (13) ◽  
pp. 249-256 ◽  
Author(s):  
Lamia Belfares ◽  
Michel Perrier ◽  
Bruce A. Ramsay ◽  
Juliana A. Ramsay ◽  
Mario Jolicoeur ◽  
...  
Keyword(s):  
Specific Growth ◽  
Biomass Concentration ◽  
Optimization Method ◽  
Model Parameters ◽  
High Biomass ◽  
Ammonium Ions ◽  
Model Predictions ◽  
Inhibition Kinetic ◽  
High Biomass Concentration ◽  
Classical Optimization

During the growth phase of Alcaligenes eutrophus, it was observed that the concentrations of glucose and ammonium ions are inhibitory at a certain level, which affects the specific growth rate. Moreover, it has been established from previous work that (an) unidentified substance(s) inhibit(s) the growth at biomass concentrations above 10 g∙L−1. A model taking into account these multiple inhibitory factors is proposed to predict the growth of A. eutrophus. The model parameters were determined by batch experiments except for the parameter associated with inhibition at high biomass concentration. This parameter was estimated by a classical optimization method. The validity of the model was tested by comparing the model predictions with experimental data obtained in batch and transient continuous fermentations and with literature data.Key words: A. eutrophus, inhibitory product, high biomass concentration.

scholarly journals Operational Monitoring and Mass Balance in the Biodegradation of Oil for Two Scenarios: Experimental Plant of Active Sludge and Aerobic Digestor

2017 ◽  
Author(s):  
Pedro Cisterna ◽  
Patricia Arancibia
Keyword(s):  
Activated Sludge ◽  
Biological Treatment ◽  
Treatment Plant ◽  
Fats And Oils ◽  
Laboratory Scale ◽  
Experimental Plant ◽  
Actual System ◽  
Load Range ◽  
Active Sludge ◽  
Mass Load

Fats and oils are the most common contaminants in wastewater and are usually discarded through physical processes. This paper studies its elimination through an environmentally friendly biological treatment, yielding good results on both laboratory scale and in the field. In this study a comparative evaluation of the biodegradation of fats and oils in two scenarios were developed in an activated sludge plant at laboratory scale, and a wastewater treatment plant. The full-scale values for some key parameters are compared, such as the oil concentration in the influent and effluent, mass loading and removal efficiency and biodegradation systems. Activated sludge plant at laboratory scale working on a mass load range from 0.2 to 0.8 (kg COD / day / kg MLSS) initially reaches levels of 75% biodegradation thereafter influent concentration is increased and thereby the mass load is increased in a range of working system under high load and biodegradation rates ranging from 71 to 64% are achieved. The actual system consists of a treatment plant wastewater with an aerobic digester for sludge treatment. Fats and oils are retained in a previous degreaser to biological treatment and subsequently sent to the aerobic sludge digester, constituting of thus on a single substrate, resembling an activated sludge plant with extended aeration mode, and levels of biodegradation in the range of 69 to 92%. From this work, we can say that the choice of biological treatment for fats and oils is feasible and adequate. Furthermore, the biomass presents great adaptability to the oil substrate, favored in this case for being the only source of carbon, therefore fats and oils should be removed using biological treatment, instead of the flotation procedure or at most using it as an intermediate process

Investigation of the Effect of Growth From Low to High Biomass Concentration Inside a Photobioreactor on Hydrodynamic Properties of Scenedesmus obliquus

2011 ◽  
Vol 134 (1) ◽  
Author(s):  
Evan Le ◽  
Chanwoo Park ◽  
Sage Hiibel
Keyword(s):  
Production Efficiency ◽  
Scenedesmus Obliquus ◽  
Biomass Concentration ◽  
High Energy ◽  
Biodiesel Production ◽  
Algal Culture ◽  
High Biomass ◽  
Algae Biodiesel ◽  
The Impact ◽  
High Biomass Concentration

Most of the current production cost in algae biodiesel plants utilizing photobioreactors comes from the high energy required for pumping, CO2 transfer, mixing, and harvesting. Since pumping affects the mixing and CO2 transfer, which are the main factors in algae productivities, solutions to reduce the required energy for pumps can significantly make algae biodiesel production more economically feasible. An investigation on the effect of Scenedesmus obliquus’s growth from low to high biomass concentration inside a horizontal tubular photobioreactor to determine the impact that it has on hydrodynamic performances, which will affect cost and production efficiency, was performed. As the biomass concentration increased, the algal culture was found to remain Newtonian. Additionally, the biomass concentration (expressed in cell density) was found to have lower viscosity even at the highest concentrations evaluated at 2.48 × 108 cell/ml (1.372 × 10−3 ± 1.32 × 10−4 Pa s) compared to the Modified Bold’s 3N medium (1.408 × 10−3 ± 9.41 × 10−5 Pa s). Furthermore, the total energy consumption does not appear to depend on the S. obliquus biomass concentrations, but rather on the medium the algae grows in. The rheological properties of autotrophic algae will not have significant impact on energy requirements until technology improves so that the concentrations reach those of heterotrophic algae.

The optimum medium of the suspended bio-medium aeration contactor process

1994 ◽  
Vol 29 (10-11) ◽  
pp. 183-188 ◽  
Author(s):  
C. F. Ouyang ◽  
C. M. Liaw
Keyword(s):  
Particle Size ◽  
Activated Carbon ◽  
Fluidized Bed ◽  
Shear Force ◽  
Biomass Concentration ◽  
Aeration Tank ◽  
High Biomass ◽  
The Media ◽  
Fluidized Bed Process ◽  
High Biomass Concentration

The purpose of this study is to modify the Fluidized Bed Process. Placing various particle diameters of granular activated carbon, (#20∼#30, #30∼#40, #40∼#50) as a medium in an aeration tank, in which microorganisms can attach and grow, improves the biomass concentration, volumetric loadings and removal efficiency. The continuous supply of substrates allows the thickness of bio-film on the medium to be shifted to a proper state. This is due to a friction force effect between the media and the shear force of the agitated flow. After studying the comparisons, it is concluded that the middle particle size (#30∼#40) is the best of the three particle diameters as a medium, in that it achieves a high biomass concentration, stable treatment and higher efficiency.

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