Ternary cycle treatment of high saline wastewater from pesticide production using a salt-tolerant microorganism

2013 ◽  
Vol 67 (9) ◽  
pp. 1960-1966 ◽  
Author(s):  
Xiang Wu ◽  
Ya-guang Du ◽  
Yi Qu ◽  
Dong-yun Du
Keyword(s):  
Gene Sequencing ◽  
Oxygen Demand ◽  
Ethyl Chloride ◽  
Aerobic Treatment ◽  
Salt Tolerant ◽  
Chemical Oxygen Demand Removal ◽  
Saline Wastewater ◽  
Nacl Concentration ◽  
Ph Range ◽  
Immobilized Microorganism

The material of this study is provided by biological aerobic treatment of high saline wastewater from pesticide production. The microorganism used for biodegradation has been identified by gene-sequencing as a strain of Bacillus sp. SCUN. The best growth condition for the salt-tolerant microorganism has been studied by varying the pH, immobilized microorganism dosage and temperature conditions. The feasibility of pretreating wastewater in ethyl chloride production containing 4% NaCl has been discussed. It was found that under the pH range of 6.0–8.0, immobilized microorganism dosage of 1.5 g/L, temperature of 30 °C, and NaCl concentration of 0–3%, the microorganism achieves the best growth for biodegradation. After domestication, the strain can grow under 4% NaCl. This salt-tolerant microorganism is effective in the pretreated high saline wastewater. With a newly developed ternary cycle treatment, the chemical oxygen demand removal approaches 58.3%. The theoretical basis and a new method for biological treatments in biodegradation of high saline wastewater in ethyl chloride production are discussed.

scholarly journals Isolation of two salt-tolerant strains from activated sludge and its COD degradation characteristics from saline organic wastewater

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Guizhong Zhou ◽  
Xitong Wang ◽  
Huiyang Zhao ◽  
Weiqian Zhang ◽  
Guishan Liu ◽  
...  
Keyword(s):  
Activated Sludge ◽  
Biological Treatment ◽  
Soluble Sugar ◽  
Oxygen Demand ◽  
Salt Tolerant ◽  
Bacterial Strains ◽  
Saline Wastewater ◽  
High Salt Stress ◽  
Relative Membrane Permeability ◽  
Organic Wastewater

Abstract The efficient biological treatment of saline wastewater has been limited by the low activities of microorganisms under saline conditions. High salinity poses unbalance osmotic stress across the cell wall and even leads to cell plasmolysis. In this work, we aim to isolate salt-tolerant bacterial strains from activated sludge, and apply them for degrading chemical oxygen demand (COD) of saline organic wastewater. Two salt-tolerant strains were screened and isolated from activated sludge, which was domesticated with salty water for over 300 days. The two strains were identified as Bacillus cereus (strain A) and Bacillus anthracis (strain B) through 16S rRNA sequencing. The degradation characteristics of strain A were explored. The results showed the relative membrane permeability of strain A remained stable under high salt stress, which glycine and proline play an important role to maintain cell osmotic. The protein and soluble sugar amounts of strain were increased by higher salt concentrations. In simulating saline wastewater, the optimum culture temperature, pH, salinity, influent COD concentration and inoculation amount of strain A were 35 °C, 9, 4%, 8000 mg L−1, 6%, respectively. Optimal conditions could provide guidance for the treatment of practical saline wastewater. The linear regression model of each impact factor built based on the result PB experiment revealed that cross-linking time has the most significant influence on COD removal for salt-tolerant strains. It will provide theoretical basis for biological treatment of saline organic wastewater.

A novel salt-tolerant mutant YWL-01 for the treatment of saline wastewater

2009 ◽  
Vol 60 (11) ◽  
pp. 2869-2877 ◽  
Author(s):  
J. Liu ◽  
G. L. Wang
Keyword(s):  
Dna Analysis ◽  
Random Amplified Polymorphic Dna ◽  
Sewage Treatment ◽  
Oxygen Demand ◽  
Salt Tolerant ◽  
Bacterial Strains ◽  
Saline Wastewater ◽  
Tolerant Mutant ◽  
Combined Mutagenesis ◽  
Salt Tolerant Mutant

The treatment of high-saline wastewater from some salt-end markets including agro-food industry is a serious problem yet to be solved in some coastal cities. The conventional physical–chemical techniques are energy-consuming and their startup and running costs are still high. Biological methods using salt-tolerant bacterial strains for the treatment of hypersaline wastewater provide one possible solution. In this study, one salt-tolerant mutant named YWL-01 was screened out by sewage treatment and proved to be a genetically stable salt-tolerant strain for saline wastewater treatment. First, combined mutagenesis was done on an isolated sewage treatment strain Bacillus Y for the screening of salt tolerance, and 11 mutants were obtained after subculture for many times. Then, a secondary screening test was performed for COD (chemical oxygen demand) and TOC (total organic carbon) removal efficiency analyses. At last, the best mutant YWL-01 with increased capacity to treat saline wastewater was chosen for use. RAPD (Random Amplified Polymorphic DNA) analysis of genetic stability on the mutant YWL-01 showed that it is a hereditary mutant for the treatment of high-saline wastewater.

Effect of Acclimation Strategy on the Biological Nitrification in the Saline Wastewater

2011 ◽  
Vol 183-185 ◽  
pp. 522-526 ◽  
Author(s):  
Ling Ling Li ◽  
Bo Yang ◽  
Peng Zhou
Keyword(s):  
Oxidation Rate ◽  
Nitrifying Bacteria ◽  
Ammonia Oxidizing Bacteria ◽  
Ammonium Oxidation ◽  
Salt Tolerant ◽  
Nitrite Oxidation ◽  
Saline Wastewater ◽  
Nacl Concentration ◽  
Nitrite Oxidizing Bacteria ◽  
Fresh Culture

During the process of cultivation of salt-tolerant nitrifying bacteria, the increase in NaCl concentrations was carried out in two different manners. The NaCl concentration in reactor A was increased by increment of 5 g/L, while the NaCl concentration in reactor B was increased by increment of 2.5 g/L. The impacts of NaCl content on the fresh culture and two acclimated cultures were investigated, which focused upon the changes of the specific ammonium oxidation rate (SAOR) and specific nitrite oxidation rate (SNOR). The results indicated that fresh nitrifiers were severely inhibited by high salinity. At NaCl concentration of 25 g/L, ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) completely lost the nitrification capability. After 46 days of acclimation, the nitrifying bacteria could be adapted to the saline wastewater. The average SAOR and SNOR in reactor B were slightly higher than those in reactor A, which meant that low increment in salt concentration may be in favor of the development of salt-tolerant nitrifiers. But the two NaCl increasing approaches did not affect the SAOR and SNOR too much. Salt-tolerant nitrifiers could be well developed with the two acclimation manners.

Reduction of COD from Micro-Polluted Water through Adsorption of Activated Carbon-Attapulgite Composite Adsorbent

2010 ◽  
Vol 450 ◽  
pp. 445-448
Author(s):  
Zheng Wang ◽  
Zhao Qian Jing ◽  
Yu Kong ◽  
Wei Shen
Keyword(s):  
Activated Carbon ◽  
Oxygen Demand ◽  
Polluted Water ◽  
Adsorption Model ◽  
Batch Mode ◽  
Composite Adsorbent ◽  
Adsorption Data ◽  
Complete Study ◽  
Ph Range ◽  
Optimum Ph Range

The aim of this study was the assessment of reduction of chemical oxygen demand (COD) from micro-polluted water using activated carbon-attapulgite composite adsorbent prepared using activated carbon and natural attapulgite through compounding, granulation and calcination. The complete study was done in batch mode to investigate the effect of operating parameters. Adsorption of COD was found to be dependent on contact time, pH, temperature and initial COD concentration. Adsorption equilibrium attained within 80 minutes time. The optimum pH range for adsorption of organics was found to be 8. The sorption of organics decreased with rise of temperature because adsorption process was exothermic. The studied adsorption data fitted well to Langmuir adsorption model with the correlation coefficient 0.9947. The activated carbon-attapulgite composite adsorbent in this study shows very good promise for practical applicability on removal of COD from micro-polluted water.

scholarly journals Impact of Partially Treated Wastewater on Downstream Water Quality of Notwane River in Botswana

2018 ◽  
pp. 1-9
Author(s):  
Gilbert K. Gaboutloeloe ◽  
Gugu Molokwe ◽  
Benedict Kayombo
Keyword(s):  
Water Quality ◽  
Pearson Correlation ◽  
Oxygen Demand ◽  
Ammonia Nitrogen ◽  
Treated Wastewater ◽  
Nitrate N ◽  
River Stretch ◽  
Ph Range ◽  
The Impact

The impact of partially treated wastewater on the water quality of Notwane river stretch in the Gaborone region of Botswana was investigated. Water samples collected at effluent discharge point and three other sampling sites downstream were analyzed for pH, temperature, Biological Oxygen Demand (BOD5), Ammonia-nitrogen (Ammonia-N) and Nitrate-nitrogen (Nitrate-N). Sampling was conducted bi-weekly between February 2013 and April 2013. The ranges of measured parameters were:  pH (7.6-8.5), temperature (22-23ºC), BOD5 (11.2-27.0 mg/l), Ammonia-N (2.4-60.5 mg/l), Nitrate-N (20.6-28.6 mg/l). Analysis of variance, Games-Howel multiple comparisons and Pearson correlation were used to separate variable means. The results signal river non-point pollution due to runoff inflow of organics mainly from land use and domestic waste dumping by nearby dwellings. Temperature, BOD5, and pH range values were all within the Botswana Bureau of Standards (BOBS) limit while the maximum Ammonia-N and Nitrate-N were above BOBS limit by 50.5 mg/l and 6.6 mg/l, respectively. Regulations on indiscriminate waste dumping and discharge standards adherence should be enforced.

scholarly journals Isolation and Assessment of the Symbiotic Efficiency of Faba bean (Vicia faba L.) Nodulating Rhizobial Isolates from Eastern Hararghe Highlands of Ethiopia

2021 ◽  
Vol 9 (2) ◽  
pp. 91-105
Author(s):  
Mulugeta Mekonnen ◽  
Ameha Kebede
Keyword(s):  
Vicia Faba ◽  
Faba Bean ◽  
Dry Weight ◽  
Symbiotic Efficiency ◽  
Shoot Dry Weight ◽  
Nacl Concentration ◽  
Vicia Faba L ◽  
Positive Correlations ◽  
Ph Range ◽  
Rhizobial Isolates

This particular work was devoted to isolate and assess the symbiotic efficiency of faba bean (Vicia faba L.)-nodulating rhizobia isolate at few faba bean growing areas of the eastern Hararghe highlands of Ethiopia. Overall 50 rhizobia isolates were obtained from soil samples of three Woredas (districts) of the eastern Hararghe highlands using the host trap method. Out of these 50 isolates, 40 were presumptively identified as rhizobia. Among these 40 rhizobia isolates, only 31 were successful to nodulate faba bean, and authenticated as true faba bean nodulating rhizobia. Concerning the symbiotic efficiency, about 52%, 35%, and 13% of the rhizobial isolates were found to be highly effective, effective, and lowly-effective, respectively. The correlation data on the sand experiment displayed that nodule dry weight was associated positively and significantly (r = 0.494, p<0.05) with shoot dry weight while shoot dry weight was associated positively and significantly (r=0.41, p<0.05) with plant total nitrogen. Positive correlations were also observed concerning shoot dry weight and dry weight of nodules (r = 0.7, p<0.05) on unsterilized soil. Among the observed rhizobium isolates, EHHFR (4A, 6A) showed the highest symbiotic efficiency above 110%, tolerated NaCl concentration ranging from 2% to 6% and 2% to 8%, respectively, and a pH range of 4.5 to 8 and 5 to 8, respectively. Thus, based on their symbiotic efficiency at the greenhouse level and relative tolerance to extreme conditions these faba bean nodulating rhizobia isolates were recommended to be used as nominees for the future development of faba bean rhizobial inoculants after being tested on field conditions.

scholarly journals Emergence of a new salt-tolerant alien grass along roadsides? Occurrence of Diplachne fusca subsp. fascicularis (Poaceae) in Hungary

2021 ◽  
Vol 80 (2) ◽  
Author(s):  
Kristóf Süveges ◽  
Attila V. Molnár ◽  
Attila Mesterházy ◽  
Júlia Tüdősné Budai ◽  
Réka Fekete
Keyword(s):  
Salt Content ◽  
Rice Paddy ◽  
Salt Tolerant ◽  
The Road ◽  
Reproduction Strategy ◽  
Temporal And Spatial Variability ◽  
Nacl Concentration ◽  
Negative Effect ◽  
Hungarian Population ◽  
Paved Road

This paper reports the occurrence of a North American salt-tolerant taxon, Diplachne fusca subsp. fascicularis (Lam.) P.M.Peterson et N.Snow in Hungary (Central-Europe). Two earlier Hungarian observations of D. fusca were known from 1915, near Győr (West Transdanubia), later the taxon was collected by Pénzes in 1958, in downtown Budatétény (central Hungary. Both observations seem to be occasional. Recently, the taxon has started spreading in Europe, mainly on rice paddy fields, with a serious invasion potential. In North America its appearance on ruderal habitats, as well as along roads and other linear infrastructures is a well known phenomenon. The Hungarian population was found near Cegléd (Central Hungary) on the roadside of the E40 primary main road in September 2018. In July 2019 more than one thousand (mostly vegetative) individuals were detected. The salt content of the habitat shows remarkable temporal and spatial variability. At one meter distance from the edge of the paved road soil salt content was higher in spring (after the winter de-icing regime), than in autumn. Salt concentration was highest in the vicinity of the road, and decreased with increasing distance from it. Germination tests revealed a significant negative effect of NaCl concentration on germination rates, but germination occurred even on extremely saline substrates with 1.5% NaCl concentration. Considering its biology and reproduction strategy, the further spread of Diplachne fusca is highly presumable.

scholarly journals Applicability of biological wastewater treatment for various industries

2021 ◽  
Vol 941 (1) ◽  
pp. 012001
Author(s):  
Basamykina Alena ◽  
Kurkina Ekaterina ◽  
Kameristaya Maria
Keyword(s):  
Organic Matter ◽  
Wastewater Treatment ◽  
Organic Matter Content ◽  
Oxygen Demand ◽  
Anaerobic Treatment ◽  
Matter Content ◽  
Biological Wastewater Treatment ◽  
Aerobic Treatment ◽  
Total Organic Matter ◽  
Inorganic Substances

Abstract Biological treatment methods are used to remove organic and some inorganic substances from wastewater using the simplest organisms that use these substances for nutrition, breaking them down using cellular processes. The article deals with the aerobic, anaerobic and anoxic stages of biological wastewater treatment. Their differences are explained and the best way to use biological processes is analyzed according to the type of industry/production. At wastewater treatment plants, anaerobic treatment is often used at first to remove a significant part of organic substances from wastewater before sending them for further aerobic treatment. Aerobic treatment is effective for various types of wastewater, especially with lower biochemical oxygen demand (BOD) and chemical oxygen demand (COD). A comparative analysis of wastewater composition from food, oil and gas processing, pharmaceutical and pulp and paper industries was carried out. In the presence of organic compounds, the technology is chosen depending on the total organic matter content or the total COD content, which characterizes the total organic matter in water. A combination of anaerobic and aerobic methods is possible, if a discharge into the sewer system or into water bodies is required. The grounds for the application of biological wastewater treatment of these industries are given.

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