Biodegradation Characteristics and Bioaugmentation Potential of an Efficient O-Cresol-Degrading Strain Isolated from Petrochemical Sewage Treatment Plant

2013 ◽  
Vol 726-731 ◽  
pp. 264-268
Author(s):  
Jia Bao Yan ◽  
Long Long Xu ◽  
Xin Wei

O-cresol and its isomers are one of the major pollutants to water environment. In this study, a highly effective o-cresol-degradation strain was isolated from the activated sludge of a petrochemical sewage treatment. Based on its morphology, physiological characteristics and 16S rDNA sequence analysis, it was identified as Pseudomonas sp. The optimal operating temperature, initial pH and rotary shaker speed for the strain to degrade o-cresol were experimentally determined to be 30°C,pH 6.5~8.0 and 150~200 rpm, respectively. Substrate scope experiment showed that the strain can degrade o-cresols other isomers and phenol. The degradation kinetics of the strain can be described by competitive substrate inhibition model with a maximum specific degradation rate of 0.055h-1. Furthermore, the bioaugmentation of the strain in the refinery wastewater to degrade o-cresol was investigated. The result showed that the strain is able to survive in refinery wastewater with high concentration of o-cresol and remove it efficiently.

2008 ◽  
Vol 58 (5) ◽  
pp. 1101-1106
Author(s):  
Pichiah Saravanan ◽  
K. Pakshirajan ◽  
P. K. Saha

An indigenous mixed culture of microorganisms, isolated from a sewage treatment plant, was investigated for its potential to simultaneously degrade phenol and m-cresol during its growth in batch shake flasks. 22 full factorial designs with the two substrates as the factors, at two different levels and two different initial concentration ranges, were employed to carry out the biodegradation experiments. For complete utilisation of phenol and m-cresol, the culture took a minimum duration of 21 hrs at their low concentration of 100 mg/L each, and a maximum duration of 187 hrs at high concentration of 600 mg/L each in the multisubstrate system. The biodegradation results also showed that the presence of phenol in low concentration range (100–300 mg/L did not inhibit m-cresol biodegradation; on the other hand, presence of m-cresol inhibited phenol biodegradation by the culture. Moreover, irrespective of the concentrations used, phenol was degraded preferentially and earlier than m-cresol. During the culture growth, a lag phase was observed above a combined concentration of 500 mg/L i.e., 200 mg/L m-cresol and 300 mg/L of phenol and above). Statistical analysis of the specific growth rate of the culture in the multisubstrate system was also performed in the form of ANOVA and Student ‘t’ test, which gave good interpretation in terms of main and interaction effects of the substrates.


2013 ◽  
Vol 67 (6) ◽  
pp. 1324-1331 ◽  
Author(s):  
X. D. Ji ◽  
M. L. Zhang ◽  
Y. Y. Ke ◽  
Y. C. Song

Zeolites were synthesized from silica-rich (SF-Z) and calcium-rich (CF-Z) fly ashes, respectively, and their performance in immobilizing ammonium and phosphate was investigated through batch experiments. The cation exchange capacity and phosphate immobilization capacity of SF-Z were identified as 2.79 meq/g and 12.97 mg/g while those of CF-Z were 0.69 meq/g and 87.41 mg/g, respectively. The mixture of SF-Z and CF-Z (MSC-Z) immobilized simultaneously ammonium and phosphate, and the ratio of SF-Z to CF-Z depended on the ammonium and phosphate concentrations in wastewater and the discharge standard. The adsorption processes of ammonium and phosphate on MSC-Z followed Ho's pseudo-second-order model and the intra-particle diffusion was a rate-controlling step. The Langmuir model produced better suitability to the equilibrium data. The thermodynamic study revealed that the adsorption of both ammonium and phosphate on MSC-Z was an endothermic reaction. After treatment by MSC-Z, the ammonium and phosphate concentrations in wastewater from a sewage treatment plant decreased from 7.45 and 1.42 mg/L to 2.06 and 0.51 mg/L, respectively, and met Surface Water Environment Quality Standard in China δ. These results show that the immobilization of ammonium and phosphate in wastewater can be achieved by the combination of zeolites synthesized from silica-rich and calcium-rich fly ashes.


2004 ◽  
Vol 46 (6) ◽  
pp. 309-313 ◽  
Author(s):  
Luciana Urbano Santos ◽  
Taís Rondello Bonatti ◽  
Romeu Cantusio Neto ◽  
Regina Maura Bueno Franco

Giardia and Cryptosporidium have caused several outbreaks of gastroenteritis in humans associated with drinking water. Contaminated sewage effluents are recognized as a potential source of waterborne protozoa. Due to the lack of studies about the occurrence of these parasites in sewage samples in Brazil, we compared the efficiency of two procedures for concentrating cysts and oocysts in activated sludge samples of one sewage treatment plant. For this, the samples were submitted to i) concentration by the ether clarification procedure (ECP) and to ii) purification by sucrose flotation method (SFM) and aliquots of the pellets were examined by immunofluorescence. Giardia cysts were present in all samples (100.0%; n = 8) when using ECP and kit 1 reagents, while kit 2 resulted in six positive samples (85.7%; n = 7). As for SFM, cysts were detected in 75.0% and 100.0% of these samples (for kit 1 and 2, respectively). Regarding Cryptosporidium, two samples (25.0%; kit 1 and 28.5% for kit 2) were detected positive by using ECP, while for SFM, only one sample (examined by kit 1) was positive (12.5%). The results of the control trial revealed Giardia and Cryptosporidium recovery efficiency rates for ECP of 54.5% and 9.6%, while SFM was 10.5% and 3.2%, respectively. Considering the high concentration detected, a previous evaluation of the activated sludge before its application in agriculture is recommended and with some improvement, ECP would be an appropriate simple technique for protozoa detection in sewage samples.


2014 ◽  
Vol 522-524 ◽  
pp. 854-860
Author(s):  
Qing Tao Zhang ◽  
Zhi Jian Zhang ◽  
Jiong Ma ◽  
Jiao Xiang

The growth performance of duckweed (Spirodela polyrrhiza) and its removal rate of nitrate and phosphorus in sewages taken from sewage treatment plant with different processes were studied. The experiments were conducted in an environmentally controlled growth chamber. Three kinds of sewages were taken from a grit chamber, a sedimentation tank, and the anoxic pond in a sewage treatment plant, respectively. The fourth kind of sewage was mixed using the sedimentation tank sewage and the anoxic pond sewage in a volumetric ratio 1:1. The weight of duckweed biomass were determined with a balance. Wastewater samples taken from the media were analyzed for total nitrogen (TN), ammonium nitrogen (NH4N), total phosphorus (TP), phosphatephosphorus (PO4P) using AA3 Continous Flow Analyzer. The results showed that Spirodela polyrrhiza grew well in sewages taken from grit chamber and sedimentation tank of a sewage treatment plant, whereas a lot of duckweed fronds were dead in the sewage taken from the anoxic pond due to the high TP (higher than 7.9 mg/L) and TN (higher than 51.6 mg/L). The suitable TN concentration for Spirodela polyrrhiza growth should not be higher than 45 mg/L. Compared with the treatments without duckweed, the NH4N concentrations were reduced more than 60% in ST and GC sewages with duckweed due to the NH4N uptake by duckweed. Spirodela polyrrhiza could remove TN efficiently in sewages with relative low concentration TN (less than 20 mg/L), while duckweed could not remove TN effectively in sewages with high concentration TN (higher than 20 mg/L). The TN concentration in GC sewage decreased greatly in the first four days, which probably brought about anaerobic condition, thus P uptake switched to net release of P, which caused the increase of the TP concentration in the GC sewage without duckweed in the last six days. O2 or oxidant should be provided for sewage treatment system using duckweed to ensure that efficient removal of TN and TP meanwhile. The TP and PO4P concentrations in the mixed sewage with duckweed increased far more than those for no-duckweed treatments, which could be related that the dead duckweed released P into the sewage.


2015 ◽  
Vol 737 ◽  
pp. 649-652
Author(s):  
Ming Li ◽  
Shuai Wang ◽  
De Chen Shan ◽  
Li Wei ◽  
Wen Jia Yin

In this study, IC anaerobic reactor was made to deal with the wastewater with high-concentration sulfate, the sludge from sewage treatment plant was put into two cells of IC reactor to domesticate sulfur-reducing bacteria (SRB), artificial water was made to simulate the wastewater with high-concentration SO42−. In order to remove the SO42− efficiently, two stages were designed in this study: sludge domestication stage and concentration strengthening stage. In sludge domestication stage, SRB could grow normally, the removal rate of SO42− was between 34.14% and 36.2%;in concentration strengthening stage, removal rate of SO42− was between 26% and 26.86%,demonstrating that SRB could grow and remove SO42− in such high-concentration SO42−( 38000 mg/L ) wastewater.


2020 ◽  
Vol 165 ◽  
pp. 02026
Author(s):  
Lintang Yu ◽  
Zhongya Tang ◽  
Li Feng ◽  
Junjie Ji

As the raising of environmental protection requirements, the outlet water (tailwater) quality standards of many sewage treatment plants need to be further improved. This paper mainly introduces the advanced treatment of tailwater from sewage treatment plant of vein industrial park by artificial ecological lake. The designed processing amount of this project was 1300 m3/d, the inlet water COD was 30 mg/L, the ammonia nitrogen content was 1.5 mg/L, and the outlet water main index reached the surface water environment quality standard (GB3838-2002) Ⅲ class water quality standard, which had improved the outlet water (tailwater) quality of sewage treatment plants and improved the regional water environment quality. By constructing an artificial landscape lake, the resource utilization of tailwater can be realized.


Energies ◽  
2018 ◽  
Vol 11 (11) ◽  
pp. 3194 ◽  
Author(s):  
Paweł Włodarczyk ◽  
Barbara Włodarczyk

Wastewater originating from the yeast industry is characterized by high concentration of pollutants that need to be reduced before the sludge can be applied, for instance, for fertilization of croplands. As a result of the special requirements associated with the characteristics of this production, huge amounts of wastewater are generated. A microbial fuel cell (MFC) forms a device that can apply wastewater as a fuel. MFC is capable of performing two functions at the same time: wastewater treatment and electricity production. The function of MFC is the production of electricity during bacterial digestion (wastewater treatment). This paper analyzes the possibility of applying yeast wastewater to play the function of a MFC (with Ni–Co cathode). The study was conducted on industrial wastewater from a sewage treatment plant in a factory that processes yeast sewage. The Ni–Co alloy was prepared by application of electrochemical method on a mesh electrode. The results demonstrated that the use of MFC coupled with a Ni–Co cathode led to a reduction in chemical oxygen demand (COD) by 90% during a period that was similar to the time taken for reduction in COD in a reactor with aeration. The power obtained in the MFC was 6.1 mW, whereas the volume of energy obtained during the operation of the cell (20 days) was 1.27 Wh. Although these values are small, the study found that this process can offer an additional level of wastewater treatment as a huge amount of sewage is generated in the process. This would provide an initial reduction in COD (and save the energy needed to aerate wastewater) as well as offer the means to generate electricity.


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