The Effect of Setting Time to the Formation of Aerobic Granular Sludge in SBAR under Low Organic Loading

2015 ◽  
Vol 744-746 ◽  
pp. 2401-2406
Author(s):  
Xia Zhao ◽  
Hao Xu ◽  
Bo Yu ◽  
Liu Yang ◽  
Ling Xiao Li

The setting time was regarded as the selection pressure to make the particles which were unable to get acclimatized to that cultivation circumstance so as to get the aerobic granular sludge which own excellent setting ability with screening and beneficiation. The internal-circulate sequencing batch airlift reactor (SBAR) process was adopted in this experiment to investigate the effect of setting time to the formation of aerobic granular sludge in SBAR under low organic loading. The results showed that aerobic granular sludge with an average particle diameter of 4.0 mm had a good settling ability with spherical or ellipsoidal, smooth and dense on surface, furthermore, the removal rates of NH3-N,TP and CODCr were 96%, 94% and 90% ,respectively. The setting time can be treated as the dominant element for the control of formation and characteristics of aerobic granular sludge to a certain degree in its forming process.

Author(s):  
Haigang Wu ◽  
Jinni Liu ◽  
Gugangke Xu ◽  
Zhaowei Ye ◽  
Jicheng Liu and Benchi Yi

We evaluated the pharmacokinetics of cefquinome sulfate (CEF) liposomes in eight healthy goats following intramuscular administration at 4 mg/kg. The average particle diameter of CEF liposomes prepared by the ethanol injection method was 335nm with a CEF entrapment efficiency of 69.56%. The elimination half-life (t1/2b) of CEF liposomes was 33.04h compared with 16.21 h for CEF injected without carrier (p less than 0.05). The area under the concentration curve (AUC) for CEF liposomes was approximately three-times greater than for CEF alone (P less than 0.05). The time-point of maximum plasma concentration of the drug (Tp) and the maximum plasma concentration (Cmax) were 4.38 h and 1.99 ìg/mL for CEF liposomes, compared with 1.86 h and 3.55 ìg/mL for CEF without carrier, respectively. 


Polymers ◽  
2021 ◽  
Vol 13 (24) ◽  
pp. 4358
Author(s):  
Nicole Janoszka ◽  
Suna Azhdari ◽  
Christian Hils ◽  
Deniz Coban ◽  
Holger Schmalz ◽  
...  

The confinement assembly of block copolymers shows great potential regarding the formation of functional microparticles with compartmentalized structure. Although a large variety of block chemistries have already been used, less is known about microdomain degradation, which could lead to mesoporous microparticles with particularly complex morphologies for ABC triblock terpolymers. Here, we report on the formation of triblock terpolymer-based, multicompartment microparticles (MMs) and the selective degradation of domains into mesoporous microparticles. A series of polystyrene-block-polybutadiene-block-poly(L-lactide) (PS-b-PB-b-PLLA, SBL) triblock terpolymers was synthesized by a combination of anionic vinyl and ring-opening polymerization, which were transformed into microparticles through evaporation-induced confinement assembly. Despite different block compositions and the presence of a crystallizable PLLA block, we mainly identified hexagonally packed cylinders with a PLLA core and PB shell embedded in a PS matrix. Emulsions were prepared with Shirasu Porous Glass (SPG) membranes leading to a narrow size distribution of the microparticles and control of the average particle diameter, d ≈ 0.4 µm–1.8 µm. The core–shell cylinders lie parallel to the surface for particle diameters d < 0.5 µm and progressively more perpendicular for larger particles d > 0.8 µm as verified with scanning and transmission electron microscopy and particle cross-sections. Finally, the selective degradation of the PLLA cylinders under basic conditions resulted in mesoporous microparticles with a pronounced surface roughness.


2011 ◽  
Vol 374-377 ◽  
pp. 1537-1540
Author(s):  
Dong Lin ◽  
Zi Yun Wen

The comparison experiments are carried out at different silica fume dosage between the silica fume with pre-treatment and the silica fume without pre-treatment. The results show that the pre-treatment of silica fume improved the strength greatly and the silica fume dosage corresponding to the strength peak somewhat moved forward from 0.20 for the cement-based materials with pre-treatment of silica fume to 0.21 for the cement-based materials without pre-treatment of silica fume. The particles distribution experiment results indicate that after the pre-treatment of silica fume, the average particle diameter of silica fume reduced from 2.865μmto 0.151μm. Based on Aim-Goff model, it is concluded that the increase in the compressive strength and flextural strength of cement-based materials with pre-treatment of silica fume, are attributed to the dispersion of silica fume agglomeration and the increase in the packing density of the cement-based materials.


2009 ◽  
Vol 60 (4) ◽  
pp. 1049-1054 ◽  
Author(s):  
S. López–Palau ◽  
J. Dosta ◽  
J. Mata-Álvarez

Aerobic granular sludge was cultivated in a sequencing batch reactor (SBR) in order to remove the organic matter present in winery wastewater. The formation of granules was performed using a synthetic substrate. The selection parameter was the settling time, as well as the alternation of feast-famine periods, the air velocity and the height/diameter ratio of the reactor. After 10 days of operation under these conditions, the first aggregates could be observed. Filamentous bacteria were still present in the reactor but they disappeared progressively. During the start-up, COD loading was increased from 2.7 to 22.5 kg COD/(m3 day) in order to obtain a feast period between 30 and 60 minutes. At this point, granules were quite round, with a particle diameter between 3.0 and 4.0 mm and an average density of 6 g L−1. After 120 days of operation, synthetic media was replaced by real winery wastewater, with a COD loading of 6 kg COD/(m3 day). The decrease of the organic load implied a reduction of the aggregate diameter and a density increase up to 13.2 g L−1. The effluent was free of organic matter and the solids concentration in the reactor reached 6 g VSS L−1.


2004 ◽  
Vol 49 (11-12) ◽  
pp. 41-46 ◽  
Author(s):  
N. Schwarzenbeck ◽  
R. Erley ◽  
P.A. Wilderer

Aerobic granular sludge was successfully cultivated in a lab-scale SBR-system treating malting wastewater with a high content of particulate organic matter (0.9 gTSS/L). At an organic loading rate (CODtotal) of 3.4 kg/(m3·d) an average removal efficiency of 50% in CODtotal and 80% in CODdissolved was achieved. Fractionation of the COD by means of particle size showed that particles with a diameter less than 25–50 μm could be removed at 80% efficiency, whereas particles bigger than 50 μm were only removed at 40% efficiency. Tracer experiments revealed a dense sessile protozoa population covering the granules. The protozoa appeared to be responsible for primary particle uptake from the wastewater.


2014 ◽  
Vol 1004-1005 ◽  
pp. 311-314
Author(s):  
Yang Zhao ◽  
Jian Wei Ren

The starch based polymer microspheres were synthesized in the system of the inverse emulsion polymerization. These polymer microspheres were characterized by Scanning Electron Microscope and Grain Size Analyzer. Adsorption behavior of starch based polymer microspheres for Pb2+ was investigated by atomic absorption spectrophotometry. The results showed that the average particle diameter of starch based polymer microspheres was about 43.9 μm, and surface of starch microsphere was rough and porous which could be beneficial to form adsorption layer. And the starch based polymer microsphere exhibited good adsorption of lead ions.


2020 ◽  
Vol 179 ◽  
pp. 45-53
Author(s):  
Fanghui Pan ◽  
Youbao Wang ◽  
Yongbin Jiang ◽  
Xinxi Zhang ◽  
Kunxiao Huang ◽  
...  

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