Effect of External Carbon Source on Denitrification in Biofilter at Low Temperature

2010 ◽  
Vol 113-116 ◽  
pp. 1358-1362
Author(s):  
Hong Jun Han ◽  
Yu Fei Li ◽  
Hong Bo Hu ◽  
Bing Wang
Keyword(s):  
Low Temperature ◽  
Carbon Source ◽  
Carbon Sources ◽  
Efficiency Enhancement ◽  
Denitrification Potential ◽  
External Carbon Source ◽  
Batch Tests ◽  
Sewage Plant ◽  
The Mean ◽  
Lower Temperature

The aim of this study is to investigate the denitrification efficiency enhancement and to evaluate the denitrification potential at the condition of lower temperature. Three identical biofilter were operated in parallel at batch tests. Results showed that the denitrification potential can be substantially increased by addition of ethanol and hydrolysate of sludge as external carbon sources compared with raw sewage. The mean denitrification rates of ethanol and hydrolysate reached up to 0.058 and 0.08 mgN/(g MLVSS•h), respectively, while that of raw sewage was only 0.041 mgN/(g MLVSS•h). The denitrification potential increased respectively from 0.76 to 1.54 and 5.3 mg NO3-N/L owing to ethanol and hydrolysate addition. By comparison, hydrolysate of sludge was found to be the better carbon source for denitrification considering strengthening denitrification performance and price. This study provides evidence for external carbon sources choice of sewage plant and surplus sludge reutilization.

scholarly journals Methane Emissions Driven by Adding a Gradient of Ethanol as Carbon Source in Integrated Vertical-Flow Constructed Wetlands

Water ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 1086
Author(s):  
Xiaoling Liu ◽  
Jingting Wang ◽  
Xiaoying Fu ◽  
Hongbing Luo ◽  
Bruce C. Anderson ◽  
...  
Keyword(s):  
Carbon Source ◽  
Constructed Wetlands ◽  
Control Experiment ◽  
Ethanol Concentration ◽  
Removal Rate ◽  
Carbon Sources ◽  
Vertical Flow ◽  
Emission Flux ◽  
Rate Range ◽  
External Carbon Source

This work aims to investigate the methane emissions from integrated vertical-flow constructed wetlands (IVCWs) when ethanol is added as an external carbon source. In this study, a gradient of ethanol (0, 2, 4, 8, 16 and 32 mmol/L) was added as the carbon source in an IVCW planted with Cyperus alternifolius L. The results showed that the methane emission flux at an ethanol concentration of 32 mmol/L was 32.34 g CH4 m−2 day−1 less than that of the control experiment (0 mmol/L) and that the methane emission flux at an ethanol concentration of 16 mmol/L was 5.53 g CH4 m−2 day−1 less than that at 0 mmol/L. In addition, variations in the water quality driven by the different ethanol concentrations were found, with a redox potential range of −64 mV to +30 mV, a pH range of 6.6–6.9, a chemical oxygen demand (COD) removal rate range of 41% to 78%, and an ammonia nitrogen removal rate range of 59% to 82% after the ethanol addition. With the average CH4-C/TOC (%) value of 35% driven by ethanol, it will be beneficial to understand that CH4-C/TOC can be considered an ecological indicator of anthropogenic methanogenesis from treatment wetlands when driven by carbon sources or carbon loading. It can be concluded that adding ethanol as an external carbon source can not only meet the water quality demand of the IVCW treatment system but also stimulate and increase the average CH4 emissions from IVCWs by 23% compared with the control experiment. This finding indicates that an external carbon source can stimulate more CH4 emissions from IVCWs and shows the importance of carbon sources during sewage treatment processes when considering greenhouse emissions from treated wetlands.

Comparative Analysis of Nitrate Removal in Sub-Surface Flow Constructed Wetlands by Different External Carbon Sources

2014 ◽  
Vol 1073-1076 ◽  
pp. 779-783
Author(s):  
Patience Awhavbera ◽  
Lian Fang Zhao
Keyword(s):  
Carbon Source ◽  
Wheat Straw ◽  
Constructed Wetlands ◽  
Nitrate Removal ◽  
Waste Product ◽  
Carbon Sources ◽  
Surface Flow ◽  
Synthetic Wastewater ◽  
External Carbon Source ◽  
N Removal

External carbon sources provide additional nutrients that improve the efficiency of nitrate removal in constructed wetlands. Typha angustifolia L. were planted in four vertical subsurface-flow constructed wetlands. Different external carbon sources were fed into the columns, to investigate and compare their treatment of nitrate in synthetic wastewater, with initial influent C/N ratio of 1:1. Wetland A (WA) with 50g wheat straw as external carbon source, wetland B (WB) with 50g woodchips, wetland C (WC) with additional 10mg/L glucose and wetland D (WD) without external carbon source to serve as the control, were used in the lab-scale experimental study. WA, WB, WC and WD within a period of 24 days, cumulatively removed 109.38mg/L, 93.75mg/L, 85.14mg/L, and 64.01mg/L nitrate, respectively, from the influent. The nitrate-nitrogen (NO3–N) removal efficiency as aided by the external carbon sources was in the order: wheat straw > woodchips > glucose > control. Wheat straw treated 93% NO3–N, woodchips 78%, glucose 72% and the control 53%. The results indicate that WA, WB and WC outperformed the control system, due to the additional carbon sources. In general, the wheat straw had a better performance than wood chips and glucose. Thus, wheat straw as low cost biological waste product is recommended for the treatment of nitrate in wetlands.

Sewage Treatment of Post-Denitrification Oxic/Anoxic Biological Filter

2011 ◽  
Vol 255-260 ◽  
pp. 2781-2785
Author(s):  
Wei Li ◽  
Xiao Min Hu ◽  
Wei Wei ◽  
Tie Heng Sun
Keyword(s):  
Carbon Source ◽  
Sewage Treatment ◽  
Carbon Sources ◽  
Denitrification Rate ◽  
Anoxic Zone ◽  
External Carbon Source ◽  
Biological Filter ◽  
Filter Process ◽  
Oxic Zone ◽  
Better Than

The paper is intended to investigate the effect of denitrification and COD removal in the post-denitrification biological filter process, adding an external carbon source. Tow carbon sources are dosed, methanol and sewage. The experiment performs in a tow-classes biological filter, oxic zone and anoxic zone, indicate that denitrification rate can be instantaneously increased through the addition of either carbon source. The perfect inputs flow of methanol and sewage are 20 mg/L and 0.2Q (Q is the effluent flow). These results indicate that methanol is better than sewage to denitrification as carbon source and the effluent concentration of COD was low.

The impact of precipitation and external carbon source addition on biological nutrient removal in activated sludge systems – experimental investigation and mathematical modeling

2012 ◽  
Vol 7 (1) ◽  
Author(s):  
J. Makinia ◽  
J. Drewnowski ◽  
M. Swinarski ◽  
K. Czerwionka ◽  
M. Kaszubowska ◽  
...  
Keyword(s):  
Carbon Source ◽  
Activated Sludge ◽  
Carbon Sources ◽  
Full Scale ◽  
Biological Nutrient Removal ◽  
Batch Experiments ◽  
Carbon Addition ◽  
Reference Case ◽  
External Carbon Source ◽  
The Impact

The aim of this study was to determine the effects of chemical precipitation and addition of external carbon sources on the denitrification capability and enhanced biological phosphorus removal (EBPR) interactions at the ‘Wschod’ WWTP (600,000 PE) in Gdansk (northern Poland). For this purpose, different kinds of batch experiments were carried out with the settled wastewater (without pretreatment and after coagulation-flocculation) and external carbon sources (ethanol and fusel oil). Precipitation of colloidal and particulate organic fractions has a significant effect on denitrification and EBPR. The removal of these two fractions by coagulation-flocculation resulted in the reduced process rates (30–70%). The experimental investigations were supported by both lab-scale and full-scale simulations using a newly developed model as an expansion of the Activated Sludge Model No. 2d (ASM2d). The new model accurately predicted the effects of precipitation and external carbon addition in batch experiments. Full-scale simulations revealed that addition of external carbon source can compensate the effects of precipitation resulting in a similar NO3-N behavior compared to the reference case (without precipitation and external carbon addition). The combined effects of precipitation and addition of external carbon source resulted in a significantly different PO4-P behavior compared to the reference case.

Advances of External Carbon Source in Denitrification

2012 ◽  
Vol 518-523 ◽  
pp. 2319-2323 ◽  
Author(s):  
Guang Ying Liu ◽  
Huan Zhen Zhang ◽  
Wei Li ◽  
Xin Zhang
Keyword(s):  
Carbon Source ◽  
Slow Release ◽  
Removal Rate ◽  
Nitrate Removal ◽  
Carbon Sources ◽  
Electron Donors ◽  
Primary Sludge ◽  
External Carbon Source ◽  
The Media ◽  
Available Carbon

Carbon source used as electron donors is critical to heterotrophic denitrification. Addition of external carbon source is necessary when internal organics are deficient. A review was conducted on the use of external carbon source in denitrification. Traditional carbon sources such as methanol and ethanol, alternative carbon sources such as cellulose-rich materials, biodegradable polymers and primary sludge are included in external carbon sources. Present situation and problems of its biodegradability and effects in denitrification are summarized. Focus in external carbon source includes further study on the biodegradation mechanism of the media, slow release performance and nitrate removal rate of available carbon source and continuous research on new kinds of substrates. Recommendations on further study of carbon source are put forward.

Influence of Carbon-Sources and C/N Ratio on the Heterotrophic Denitrification

2013 ◽  
Vol 295-298 ◽  
pp. 259-263
Author(s):  
Jing Chen ◽  
Bo Li ◽  
Ning Wang ◽  
Hong Juan Li ◽  
Dong Jin Wan
Keyword(s):  
Carbon Source ◽  
Carbon Sources ◽  
External Carbon Source ◽  
Heterotrophic Denitrification

The effects of external Carbon-source (both type and C/N ratio) on heterotrophic denitrification were evaluated. Glucose, methanol and ethanol were chose as the C-sources, and the optimal C/N ratio of ethanol was decided as 2 while that of glucose and methanol is 6.5 and 2.5 respectively. Compared with methanol and glucose, ethanol is more efficiency, its average denitrifying rate was 1.2483 mg/g•h.This template explains and demonstrates how to prepare your camera-ready paper for Trans Tech Publications. The best is to read these instructions and follow the outline of this text.

Effect of carbon source on Phenobarbital metabolism by Rhizopus stolonifer

2010 ◽  
Vol 3 (2) ◽  
pp. 1022-1027
Author(s):  
Kavitha K ◽  
Asha S ◽  
Hima Bindu T.V.L ◽  
Vidyavathi M
Keyword(s):  
Carbon Source ◽  
High Performance ◽  
Carbon Sources ◽  
In Vitro Models ◽  
Rhizopus Stolonifer ◽  
Safety And Efficacy ◽  
Alternative Systems ◽  
Toxicological Studies ◽  
Microbial Model

The safety and efficacy of a drug is based on its metabolism or metabolite formed. The metabolism of drugs can be studied by different in vitro models, among which microbial model became popular. In the present study, eight microbes were screened for their ability to metabolize phenobarbital in a manner comparable to humans with a model to develop alternative systems to study human drug metabolism. Among the different microbes screened, a filamentous fungi Rhizopus stolonifer metabolized phenobarbital to its metabolite which is used for further pharmacological and toxicological studies. The transformation of phenobarbital was identified by high- performance liquid chromatography (HPLC). Interestingly, Rhizopus stolonifer sample showed an extra metabolite peak at 3.11min. compared to its controls. The influence of different carbon sources in media used for growth of fungus, on metabolite production was studied, to find its effect in production of metabolite as the carbon source may influence the growth of the cell.

scholarly journals Denitrification Control in a Recirculating Aquaculture System—A Simulation Study

Processes ◽  
2020 ◽  
Vol 8 (10) ◽  
pp. 1306
Author(s):  
Pedro Almeida ◽  
Laurent Dewasme ◽  
Alain Vande Wouwer
Keyword(s):  
Carbon Source ◽  
Carbon Sources ◽  
Aquatic Organisms ◽  
Operating Conditions ◽  
Toxic Substances ◽  
Recirculating Aquaculture System ◽  
Treatment Technology ◽  
Tuning Method ◽  
Recirculating Aquaculture ◽  
Aquaculture System

The recirculating aquaculture system (RAS) is a land-based water treatment technology, which allows for farming aquatic organisms, such as fish, by reusing the water in the production (often less than 5%). This technology is based on the use of filters, either mechanical or biological, and can, in principle, be used for any species grown in aquaculture. Due to the low recirculation rate, ammonia accumulates in the system and must be converted into nitrate using nitrification reactors. Although less toxic for fish, nitrate can also be further reduced into nitrogen gas by the use of denitrification biofilters which may create several issues, such as incomplete denitrification, resulting in toxic substances, such as nitrite and nitric oxide, or a waste of carbon source in excess. Control of the added quantity of carbon source in the denitrification biofilter is then mandatory to keep nitrate/nitrite concentrations under toxic levels for fish and in accordance with local effluent regulations, and to reduce costs related to wasted organic carbon sources. This study therefore investigates the application of different control methodologies to a denitrification reactor in a RAS. To this end, a numerical simulator is built to predict the RAS behavior and to allow for the comparison of different control approaches, in the presence of changes in the operating conditions, such as fish density and biofilter removal efficiency. First, a classical proportional-integral-derivative (PID) controller was designed, based on an SIMC tuning method depending on the amount of ammonia excreted by fish. Then, linearizing and cascade controllers were considered as possible alternatives.

scholarly journals Fast oxygen ion migration in Cu–In–oxide bulk and its utilization for effective CO2 conversion at lower temperature

2021 ◽  
Author(s):  
Jun-Ichiro Makiura ◽  
Takuma Higo ◽  
Yutaro Kurosawa ◽  
Kota Murakami ◽  
Shuhei Ogo ◽  
...  
Keyword(s):  
Low Temperature ◽  
Water Gas Shift ◽  
Chemical Looping ◽  
Co2 Conversion ◽  
Ion Migration ◽  
Oxygen Ion ◽  
Reverse Water Gas Shift ◽  
Oxygen Ion Migration ◽  
Lower Temperature ◽  
Water Gas

Efficient activation of CO2 at low temperature was achieved by reverse water–gas shift via chemical looping (RWGS-CL) by virtue of fast oxygen ion migration in a Cu–In structured oxide, even at lower temperatures.

scholarly journals The carbon source-dependent pattern of antimicrobial activity and gene expression in Pseudomonas donghuensis P482

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Marta Matuszewska ◽  
Tomasz Maciąg ◽  
Magdalena Rajewska ◽  
Aldona Wierzbicka ◽  
Sylwia Jafra
Keyword(s):  
Gene Expression ◽  
Antimicrobial Activity ◽  
Carbon Source ◽  
Reference Genes ◽  
Plant Pathogens ◽  
Plant Protection ◽  
Carbon Sources ◽  
Unknown Compound ◽  
Fungal Plant Pathogens ◽  
The Impact

AbstractPseudomonas donghuensis P482 is a tomato rhizosphere isolate with the ability to inhibit growth of bacterial and fungal plant pathogens. Herein, we analysed the impact of the carbon source on the antibacterial activity of P482 and expression of the selected genes of three genomic regions in the P482 genome. These regions are involved in the synthesis of pyoverdine, 7-hydroxytropolone (7-HT) and an unknown compound (“cluster 17”) and are responsible for the antimicrobial activity of P482. We showed that the P482 mutants, defective in these regions, show variations and contrasting patterns of growth inhibition of the target pathogen under given nutritional conditions (with glucose or glycerol as a carbon source). We also selected and validated the reference genes for gene expression studies in P. donghuensis P482. Amongst ten candidate genes, we found gyrB, rpoD and mrdA the most stably expressed. Using selected reference genes in RT-qPCR, we assessed the expression of the genes of interest under minimal medium conditions with glucose or glycerol as carbon sources. Glycerol was shown to negatively affect the expression of genes necessary for 7-HT synthesis. The significance of this finding in the light of the role of nutrient (carbon) availability in biological plant protection is discussed.

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