Degradation of Chlorophenols Using Pentachlorophenol-Degrading Bacteria Sphingomonas chlorophenolica in a Batch Reactor

2005 ◽  
Vol 51 (3) ◽  
pp. 156-160 ◽  
Author(s):  
Chu-Fang Yang ◽  
Chi-Mei Lee ◽  
Chun-Chin Wang
Keyword(s):  
Batch Reactor ◽  
Degrading Bacteria ◽  
Sphingomonas Chlorophenolica

RNA/DNA ratio as an indicator of metabolic activity in resin acid-degrading bacteria

1998 ◽  
Vol 37 (4-5) ◽  
pp. 89-93 ◽  
Author(s):  
A. F. Muttray ◽  
W. W. Mohn
Keyword(s):  
Growth Rate ◽  
Batch Reactor ◽  
Resin Acid ◽  
Rate Dependent ◽  
Hybridization Probes ◽  
Specific Hybridization ◽  
Degrading Bacteria ◽  
Positive Linear Correlation ◽  
Metabolic Activities ◽  
Species Specific

We investigated the relationship between the growth rate and the ratio of RNA to DNA in of four resin acid degrading bacteria isolated from a sequencing batch reactor (SBR). Chemical assays as well as slot blot hybridizations with species-specific oligonucleotide probes were used to quantify the nucleic acids. These slow-growing bacteria have a positive linear correlation between growth rate and RNA/DNA ratio, similar to faster-growing bacteria like E. coli. We propose to use this correlation to measure metabolic activities of selected resin acid degrading bacteria in the complex community of the SBR in situ using species-specific hybridization probes. Preliminary experiments suggest that hybridization probes can be used to detect growth rate-dependent changes in the RNA/DNA ratio.

Acclimation of activated sludge to degrade toxic levels of 2,4-dinitrophenol

2004 ◽  
Vol 50 (5) ◽  
pp. 45-50
Author(s):  
Kwan-Hyung Jo ◽  
JoAnn Silverstein
Keyword(s):  
Activated Sludge ◽  
Sequencing Batch Reactor ◽  
Batch Reactor ◽  
Rapid Degradation ◽  
Degrading Bacteria ◽  
Gradual Accumulation ◽  
Time Required

Biodegradation of 75 and 100 mg/l of 2,4-dinitrophenol (DNP) by activated sludge acclimated in a Sequencing Batch Reactor (SBR) consistently required less than 6 hours although a lag at the beginning of every 48-hour SBR cycle was observed. Other investigators have reported that DNP levels of 100 mg/l and higher are significantly toxic even to acclimated bacteria. The activated sludge acclimated to 75 mg/l initial DNP had over 100 times the DNP-degrading bacteria than an SBR acclimated to 10 mg/l DNP, although the MLSS concentration in both reactors was similar. Results suggest that two mechanisms are responsible for activated sludge acclimation to toxic levels of DNP: maintenance of DNP-degrading biomass sufficiently large to reduce initial DNP to non-toxic levels, allowing for subsequent rapid degradation; and extension of the aeration period well beyond the time required for degradation to prevent gradual accumulation of any by-product which might also be toxic.

Photocatalytic degradation of methylene blue from aqueous solutions using nanopillars-TiO2 thin films: Batch reactor studies

2018 ◽  
Vol 18 (3) ◽  
pp. 81-91 ◽  
Author(s):  
C. Lalhriatpuia
Keyword(s):  
Thin Films ◽  
Methylene Blue ◽  
Photocatalytic Activity ◽  
Organic Carbon ◽  
Photocatalytic Degradation ◽  
Batch Reactor ◽  
Tio2 Thin Films ◽  
Initial Concentration ◽  
Bet Specific Surface Area ◽  
Interfering Ions

Nanopillars-TiO2 thin films was obtained on a borosilicate glass substrate with (S1) and without (S2) polyethylene glycol as template. The photocatalytic behaviour of S1 and S2 thin films was assessed inthe degradation of methylene blue (MB) dye from aqueous solution under batch reactor operations. The thin films were characterized by the SEM, XRD, FTIR and AFM analytical methods. BET specific surface area and pore sizes were also obtained. The XRD data confirmed that the TiO2 particles are in its anatase mineral phase. The SEM and AFM images indicated the catalyst is composed with nanosized pillars of TiO2, evenly distributed on the surface of the substrate. The BET specific surface area and pore sizes of S1 and S2 catalyst were found to be 5.217 and 1.420 m2/g and 7.77 and 4.16 nm respectively. The photocatalytic degradation of MB was well studied at wide range of physico-chemical parameters. The effect of solution pH (pH 4.0 to 10.0) and MB initial concentration (1.0 to 10.0 mg/L) was extensively studied and the effect of several interfering ions, i.e., cadmium nitrate, copper sulfate, zinc chloride, sodium chloride, sodium nitrate, sodium nitrite, glycine, oxalic acid and EDTA in the photocatalytic degradation of MB was demonstrated. The maximum percent removal of MB was observed at pH 8.0 beyond which it started decreasing and a low initial concentration of the pollutant highly favoured the photocatalytic degradation using thin films and the presence of several interfering ions diminished the photocatalytic activity of thin films to some extent. The overall photocatalytic activity was in the order: S2 > S1 > UV. The photocatalytic degradation of MB was followed the pseudo-first-order rate kinetics. The mineralization of MB was studied with total organic carbon measurement using the TOC (total organic carbon) analysis.

Urban pollution control strategy: SBR technology to treat agricultural waste from pig farm in Indonesia

2019 ◽  
Vol 2 (2) ◽  
pp. 21
Author(s):  
Lindawati Lindawati
Keyword(s):  
Cost Estimation ◽  
Batch Reactor ◽  
Agricultural Waste ◽  
Cost Effective ◽  
Land Application ◽  
Pig Manure ◽  
Small Scale ◽  
Piggery Wastewater ◽  
Pig Farm ◽  
Number Of Customers

Reduction of food rations and shortages is one of the impacts of the increasing human population. Food sector industries then try to cope with the fast growing number of customers. Agribusiness sector gains its popularity in these recent years, including pig farm. The increase trend of animal farming industry is likely to bring increasing pollution problem unless effective treatment methods are used. The main problems related to the pig farm include odor nuisance and pig manure disposal. The existing land application of piggery wastewater is the traditional way to discharge the wastewater. This may yield in land and water contamination, due to the accumulation of unused nutrients by crop plant. A case study of a large commercial pig farm from Australia is proposed to apply in smaller scale in Indonesia. Operational strategies for the small-scale SBR (Sequencing Batch Reactor) treating piggery effluent were developed based on lab-scale experiments. Due to SBR characteristics, which are money-saving and space-saving, it is very suitable to be applied in urban area. An economic evaluation was made of various process options. The cost estimation showed that SBR is a cost effective process, allowing operational batches to be adjusted to reduce unnecessary aeration cost. A reduction in the aeration cost was achieved by shortening the batch time from 24-h to 8-h. A comparison of three different SBR options showed that smaller size reactors could be more flexible and cost effective when compared with the larger ones.

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