Efficiency of removal of bod5 and ss in sedimentation tanks and filters in wastewater treatment systems for coffee bean (Coffea arabica processing

Directory of Open Access Journals (Sweden)

Nelson Gutiérrez Guzmán

2014-12-01

Full Text Available n order to evaluate the current operating conditions of wastewater treatment systems of small scale coffee growers in the south of Huila a lab-scale prototype (S 1:25 was constructed. It was composed of both a sediment tank and a filter fit in series, simulating similar operating conditions used by coffee producers. Removal of biological oxygen demand (BOD5 and suspended solids (SS was performed in wastewater from coffee bean processing. A 23 factorial experimental design for the evaluation of the type of sedimentation tank, type of filter and hydraulic retention time (HRT in the sedimentation tank was employed. The results showed high removal efficiencies of suspended solid concentrations (more than 95%, and low removal efficiencies in BOD5 (about 20%. The combination of tank type 1 (square with a lower area, filter type 1 (upflow anaerobic filter – UAF and HRT of 30 hours had the highest removal efficiency.

Effects of Operating Parameters on Measurements of Biochemical Oxygen Demand Using a Mediatorless Microbial Fuel Cell Biosensor

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Min-Chi Hsieh

2015-12-01

Full Text Available The conventional Biochemical Oxygen Demand (BOD method takes five days to analyze samples. A microbial fuel cell (MFC may be an alternate tool for rapid BOD determination in water. However, a MFC biosensor for continuous BOD measurements of water samples is still unavailable. In this study, a MFC biosensor inoculated with known mixed cultures was used to determine the BOD concentration. Effects of important parameters on establishing a calibration curve between the BOD concentration and output signal from the MFC were evaluated. The results indicate monosaccharides were good fuel, and methionine, phenylalanine, and ethanol were poor fuels for electricity generation by the MFC. Ions in the influent did not significantly affect the MFC performance. CN− in the influent could alleviate the effect of antagonistic electron acceptors on the MFC performance. The regression equation for BOD concentration and current density of the biosensor was y = 0.0145x + 0.3317. It was adopted to measure accurately and continuously the BOD concentration in actual water samples at an acceptable error margin. These results clearly show the developed MFC biosensor has great potential as an alternative BOD sensing device for online measurements of wastewater BOD.

Rapid adaptation of activated sludge bacteria into a glycogen accumulating biofilm enabling anaerobic BOD uptake.

Science.gov (United States)

Hossain, Md Iqbal; Paparini, Andrea; Cord-Ruwisch, Ralf

2017-03-01

Glycogen accumulating organisms (GAO) are known to allow anaerobic uptake of biological oxygen demand (BOD) in activated sludge wastewater treatment systems. In this study, we report a rapid transition of suspended activated sludge biomass to a GAO dominated biofilm by selective enrichment using sequences of anaerobic loading followed by aerobic exposure of the biofilm to air. The study showed that within eight weeks, a fully operational, GAO dominated biofilm had developed, enabling complete anaerobic BOD uptake at a rate of 256mg/L/h. The oxygen uptake by the biofilm directly from the atmosphere had been calculated to provide significant energy savings. This study suggests that wastewater treatment plant operators can convert activated sludge systems readily into a "passive aeration" biofilm that avoids costly oxygen transfer to bulk wastewater solution. The described energy efficient BOD removal system provides an opportunity to be coupled with novel nitrogen removal processes such as anammox. Copyright © 2016. Published by Elsevier Ltd.

Electrocoagulation process to Chemical and Biological Oxygen Demand treatment from carwash grey water in Ahvaz megacity, Iran.

Science.gov (United States)

Mohammadi, Mohammad Javad; Takdastan, Afshin; Jorfi, Sahand; Neisi, Abdolkazem; Farhadi, Majid; Yari, Ahmad Reza; Dobaradaran, Sina; Khaniabadi, Yusef Omidi

2017-04-01

In this work, we present the result of an electric coagulation process with iron and aluminum electrodes for removal of chemical and biological oxygen demand (COD and BOD) from grey water in different car washes of Ahvaz, Iran. Nowadays, one of the important dangerous that can contaminate water resources for drinking, agriculture and industrial is Car wash effluent [1,2]. In this study, initial COD and BOD concentration, pH of the solution, voltage power and reaction time was investigated. The concentration level of remaining COD and BOD in samples was measured, using DR/5000 UV-vis HACH spectrophotometer [3,4]. The effects of contact time, initial pH, electrical potential and voltage data on removal of COD and BOD were presented. Statistical analysis of the data was carried out using Special Package for Social Sciences (SPSS 16).

Electrocoagulation process to Chemical and Biological Oxygen Demand treatment from carwash grey water in Ahvaz megacity, Iran

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Mohammad Javad Mohammadi

2017-04-01

Full Text Available In this work, we present the result of an electric coagulation process with iron and aluminum electrodes for removal of chemical and biological oxygen demand (COD and BOD from grey water in different car washes of Ahvaz, Iran. Nowadays, one of the important dangerous that can contaminate water resources for drinking, agriculture and industrial is Car wash effluent [1,2]. In this study, initial COD and BOD concentration, pH of the solution, voltage power and reaction time was investigated. The concentration level of remaining COD and BOD in samples was measured, using DR/5000 UV–vis HACH spectrophotometer [3,4]. The effects of contact time, initial pH, electrical potential and voltage data on removal of COD and BOD were presented. Statistical analysis of the data was carried out using Special Package for Social Sciences (SPSS 16.

PREDICTION OF BOD AND COD OF A REFINERY WASTEWATER USING MULTILAYER ARTIFICIAL NEURAL NETWORKS

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Eldon Raj Rene

2008-06-01

Full Text Available In the recent past, artificial neural networks (ANNs have shown the ability to learn and capture non-linear static or dynamic behaviour among variables based on the given set of data. Since the knowledge of internal procedure is not necessary, the modelling can take place with minimum previous knowledge about the process through proper training of the network. In the present study, 12 ANN based models were proposed to predict the Biochemical Oxygen Demand (BOD5 and Chemical Oxygen Demand (COD concentrations of wastewater generated from the effluent treatment plant of a petrochemical industry. By employing the standard back error propagation (BEP algorithm, the network was trained with 103 data points for water quality indices such as Total Suspended Solids (TSS, Total Dissolved Solids (TDS, Phenol concentration, Ammoniacal Nitrogen (AMN, Total Organic Carbon (TOC and Kjeldahl’s Nitrogen (KJN to predict BOD and COD. After appropriate training, the network was tested with a separate test data and the best model was chosen based on the sum square error (training and percentage average relative error (% ARE for testing. The results from this study reveal that ANNs can be accurate and efficacious in predicting unknown concentrations of water quality parameters through its versatile training process.

Use of one- and two-mediator systems for developing a BOD biosensor based on the yeast Debaryomyces hansenii.

Science.gov (United States)

Zaitseva, A S; Arlyapov, V A; Yudina, N Yu; Alferov, S V; Reshetilov, A N

2017-03-01

We investigated the use of one- and two-mediator systems in amperometric BOD biosensors (BOD, biochemical oxygen demand) based on the yeast Debaryomyces hansenii. Screening of nine mediators potentially capable of electron transfer - ferrocene, 1,1'-dimethylferrocene, ferrocenecarboxaldehyde, ferroceneacetonitrile, neutral red, 2,6-dichlorophenolindophenol, thionine, methylene blue and potassium ferricyanide - showed only ferrocene and neutral red to be efficient electron carriers for the eukaryotes studied. Two-mediator systems based on combinations of the investigated compounds were used to increase the efficiency of electron transfer. The developed two-mediator biosensors exceeded their one-mediator analogs by their characteristics. The most preferable two-mediator system for developing a BOD biosensor was a ferrocene-methylene blue combination that ensured a satisfactory long-time stability (43 days), selectivity, sensitivity (the lower limit of the determined BOD 5 concentrations, 2.5mg О 2 /dm 3 ) and speed (assay time for one sample, not greater than 10min) of BOD determination. Analysis of water samples showed that the use of a ferrocene-methylene blue two-mediator system and the yeast D. hansenii enabled registration of data that highly correlated with the results of the standard method (R=0.9913). Copyright © 2017 Elsevier Inc. All rights reserved.

A Mediated BOD Biosensor Based on Immobilized B. Subtilis on Three-Dimensional Porous Graphene-Polypyrrole Composite

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Jingfang Hu

2017-11-01

Full Text Available We have developed a novel mediated biochemical oxygen demand (BOD biosensor based on immobilized Bacillus subtilis (B. subtilis on three-dimensional (3D porous graphene-polypyrrole (rGO-PPy composite. The 3D porous rGO-PPy composite was prepared using hydrothermal method following with electropolymerization. Then the 3D porous rGO-PPy composite was used as a support for immobilizing negatively charged B. subtilis denoted as rGO-PPy-B through coordination and electrostatic interaction. Further, the prepared rGO-PPy-B was used as a microbial biofilm for establishing a mediated BOD biosensor with ferricyanide as an electronic acceptor. The indirect determination of BOD was performed by electrochemical measuring ferrocyanide generated from a reduced ferricyanide mediator using interdigited ultramicroelectrode array (IUDA as the working electrode. The experimental results suggested a good linear relationship between the amperometric responses and BOD standard concentrations from 4 to 60 mg/L, with a limit detection of 1.8 mg/L (S/N ≥ 3. The electrochemical measurement of real water samples showed a good agreement with the conventional BOD5 method, and the good anti-interference as well as the long-term stability were well demonstrated, indicating that the proposed mediated BOD biosensor in this study holds a potential practical application of real water monitoring.

A reduced-order adaptive neuro-fuzzy inference system model as a software sensor for rapid estimation of five-day biochemical oxygen demand

Science.gov (United States)

Noori, Roohollah; Safavi, Salman; Nateghi Shahrokni, Seyyed Afshin

2013-07-01

The five-day biochemical oxygen demand (BOD5) is one of the key parameters in water quality management. In this study, a novel approach, i.e., reduced-order adaptive neuro-fuzzy inference system (ROANFIS) model was developed for rapid estimation of BOD5. In addition, an uncertainty analysis of adaptive neuro-fuzzy inference system (ANFIS) and ROANFIS models was carried out based on Monte-Carlo simulation. Accuracy analysis of ANFIS and ROANFIS models based on both developed discrepancy ratio and threshold statistics revealed that the selected ROANFIS model was superior. Pearson correlation coefficient (R) and root mean square error for the best fitted ROANFIS model were 0.96 and 7.12, respectively. Furthermore, uncertainty analysis of the developed models indicated that the selected ROANFIS had less uncertainty than the ANFIS model and accurately forecasted BOD5 in the Sefidrood River Basin. Besides, the uncertainty analysis also showed that bracketed predictions by 95% confidence bound and d-factor in the testing steps for the selected ROANFIS model were 94% and 0.83, respectively.

BOD-DO modeling and water quality analysis of a waste water outfall off Kochi, west coast of India

Digital Repository Service at National Institute of Oceanography (India)

Babu, M.T.; Das, V.K.; Vethamony, P.

Water quality scenarios around an offshore outfall off Kochi were simulated using MIKE21 water quality model, assuming a high Biochemical Oxygen Demand (BOD=50 mgl sup(-1)) effluent discharge. The discharge is introduced into the model through...

Submersible microbial fuel cell sensor for monitoring microbial activity and BOD in groundwater: Focusing on impact of anodic biofilm on sensor applicability

DEFF Research Database (Denmark)

Zhang, Yifeng; Angelidaki, Irini

2011-01-01

was required for application of the sensor for microbial activity measurement, while biofilm‐colonized anode was needed for utilizing the sensor for BOD content measurement. The current density of SUMFC sensor equipped with a biofilm‐colonized anode showed linear relationship with BOD content, to up to 250 mg......A sensor, based on a submersible microbial fuel cell (SUMFC), was developed for in situ monitoring of microbial activity and biochemical oxygen demand (BOD) in groundwater. Presence or absence of a biofilm on the anode was a decisive factor for the applicability of the sensor. Fresh anode...

[Pollution load and the first flush effect of BOD5 and COD in urban runoff of Wenzhou City].

Science.gov (United States)

Wang, Jun; Bi, Chun-juan; Chen, Zhen-lou; Zhou, Dong

2013-05-01

Four typical rainfalls were monitored in two different research areas of Wenzhou Municipality. Concentrations of BOD5 and COD in six different urban runoffs were measured. In addition the event mean concentration (EMC), M (V) curve and BOD5/COD of pollutant were calculated. The results showed that concentrations of BOD5 and COD in different urban runoffs of Wenzhou ranged from ND to 69.21 mg x L(-1) and ND to 636 mg x L(-1). Concentrations of BOD5 and COD in different urban runoffs were decreasing over time, so it is greatly significant to manage the initial runoff for reducing organic pollution. Judged by EMC of BOD5 and COD in these five rainfalls, concentrations of pollutant in some urban runoffs were out of the integrated wastewater discharge standard. If these runoffs flowed into river, it would cause environmental pressure to the next level receiving water bodies. According to the M (V) curve, the first flush effect of COD in most urban runoffs was common; while the first flush effect of BOD5 was same as that of COD. The result also showed that organic pollution was serious at the beginning of runoff. The underlying surface type could affect the concentration of BOD5 and COD in urban runoff. While the results of BOD5/COD also suggested that biodegradation was considered as one of the effective ways to decrease the pollution load of organics in urban runoff, and the best management plans (BMPs) should be selected for various urban runoff types for the treatment of organic pollution.

What is the Effect of Case-Based Learning on the Academic Achievement of Students on the Topic of "Biochemical Oxygen Demand?"

Science.gov (United States)

Günter, Tuğçe; Alpat, Sibel Kılınç

2017-11-01

The purpose of this study was to investigate the effect of the case-based learning (CBL) method used in "biochemical oxygen demand (BOD)," which is a topic taught in the environmental chemistry course, at Dokuz Eylul University, on the academic achievement and opinions of students. The research had a quasi-experimental design and the study group consisted of 4th and 5th grade students (N = 18) attending the Chemistry Teaching Program in a university in Izmir. The "Biochemical Oxygen Demand Achievement Test (BODAT)" and the structured interview form were used as data collection tools. The results of BODAT post-test showed the higher increase in the achievement scores of the experimental group may be an indication of the effectiveness of the CBL method in improving academic achievement in the relevant topic. In addition, the experimental and control group students had positive opinions regarding the method, the scenario, and the material. The students found the method, the scenario, and the material to be interesting, understandable/instructional, relatable with everyday life, suitable for the topic, and enhancing active participation.

Experimental demonstration of bandwidth on demand (BoD) provisioning based on time scheduling in software-defined multi-domain optical networks

Science.gov (United States)

Zhao, Yongli; Li, Yajie; Wang, Xinbo; Chen, Bowen; Zhang, Jie

2016-09-01

A hierarchical software-defined networking (SDN) control architecture is designed for multi-domain optical networks with the Open Daylight (ODL) controller. The OpenFlow-based Control Virtual Network Interface (CVNI) protocol is deployed between the network orchestrator and the domain controllers. Then, a dynamic bandwidth on demand (BoD) provisioning solution is proposed based on time scheduling in software-defined multi-domain optical networks (SD-MDON). Shared Risk Link Groups (SRLG)-disjoint routing schemes are adopted to separate each tenant for reliability. The SD-MDON testbed is built based on the proposed hierarchical control architecture. Then the proposed time scheduling-based BoD (Ts-BoD) solution is experimentally demonstrated on the testbed. The performance of the Ts-BoD solution is evaluated with respect to blocking probability, resource utilization, and lightpath setup latency.

Removal of chemical oxygen demand from textile wastewater using a natural coagulant

Energy Technology Data Exchange (ETDEWEB)

Ramavandi, Bahman [Bushehr University of Medical Sciences, Bushehr (Iran, Islamic Republic of); Farjadfard, Sima [Islamic Azad University, Tehran (Iran, Islamic Republic of)

2014-01-15

A biomaterial was successfully synthesized from Plantago ovata by using an FeCl{sub 3}-induced crude extract (FCE). The potential of FCE to act as a natural coagulant was tested for the pretreatment of real textile wastewater. Tests were performed to evaluate the effects of FCE quantity, salt concentration, and wastewater pH on chemical oxygen demand (COD) reduction during a coagulation/flocculation process. Experimental results indicated that the wastewater could be effectively treated by using a coagulation/flocculation process, where the BOD{sub 5}/COD ratio of the effluent was improved to 0.48. A low coagulant dose, 1.5mg/L, achieved a high COD removal percentage, 89%, at operational conditions of neutral pH and room temperature. The experimental data revealed that the maximum COD removal occurred at water pH<8. Increasing the salt promoted the COD removal. The settling and filterability characteristics of the sludge were also studied. Scanning electron microscopy and energy dispersive spectroscopy studies were conducted to determine the sludge structure and composition, respectively. Overall, FCE as an eco-friendly biomaterial was revealed to be a very efficient coagulant and a promising option for the removal of COD from wastewaters.

Performance of a modified multi-stage bubble column reactor for lead(II) and biological oxygen demand removal from wastewater using activated rice husk

International Nuclear Information System (INIS)

Sahu, J.N.; Agarwal, S.; Meikap, B.C.; Biswas, M.N.

2009-01-01

The excessive release of wastewater into the environment is a major concern worldwide. Adsorption is the one of the most effective technique for treatment of wastewater. In this work activated carbon prepared from rice husk has been used as an adsorbent. In the present investigation a three phase modified multi-stage bubble column reactor (MMBCR) has been designed to remove lead and biochemical oxygen demand (BOD) from wastewater by means of its adsorption onto the surface of activated rice husk. The multi-staging has been achieved by hydrodynamically induced continuous bubble generation, breakup and regeneration. Under optimum conditions, maximum lead and BOD reduction achieved using activated rice husk was 77.15% and 19.05%, respectively. Results showed MMBCR offered appreciated potential benefits for lead removal from wastewater and BOD removal, even this extent of removal is encouraging and the MMBCR can be used a pretreatment unit before subjecting the wastewater to biological treatment

Performance of a modified multi-stage bubble column reactor for lead(II) and biological oxygen demand removal from wastewater using activated rice husk.

Science.gov (United States)

Sahu, J N; Agarwal, S; Meikap, B C; Biswas, M N

2009-01-15

The excessive release of wastewater into the environment is a major concern worldwide. Adsorption is the one of the most effective technique for treatment of wastewater. In this work activated carbon prepared from rice husk has been used as an adsorbent. In the present investigation a three phase modified multi-stage bubble column reactor (MMBCR) has been designed to remove lead and biochemical oxygen demand (BOD) from wastewater by means of its adsorption onto the surface of activated rice husk. The multi-staging has been achieved by hydrodynamically induced continuous bubble generation, breakup and regeneration. Under optimum conditions, maximum lead and BOD reduction achieved using activated rice husk was 77.15% and 19.05%, respectively. Results showed MMBCR offered appreciated potential benefits for lead removal from wastewater and BOD removal, even this extent of removal is encouraging and the MMBCR can be used a pretreatment unit before subjecting the wastewater to biological treatment.

Flame-Oxidized Stainless-Steel Anode as a Probe in Bioelectrochemical System-Based Biosensors to Monitor the Biochemical Oxygen Demand of Wastewater

Directory of Open Access Journals (Sweden)

Qiaochu Liang

2018-02-01

Full Text Available Biochemical oxygen demand (BOD is a widely used index of water quality in wastewater treatment; however, conventional measurement methods are time-consuming. In this study, we analyzed a novel flame-oxidized stainless steel anode (FO-SSA for use as the probe of bioelectrochemical system (BES-based biosensors to monitor the BOD of treated swine wastewater. A thinner biofilm formed on the FO-SSA compared with that on a common carbon-cloth anode (CCA. The FO-SSA was superior to the CCA in terms of rapid sensing; the response time of the FO-SSA to obtain the value of R2 > 0.8 was 1 h, whereas the CCA required 4 h. These results indicate that the FO-SSA offers better performance than traditional CCAs in BES biosensors and can be used to improve biomonitoring of wastewater.

Oxygen enriched air using membrane for palm oil wastewater treatment

Directory of Open Access Journals (Sweden)

Ramlah Mohd Tajuddin

2002-11-01

Full Text Available A research aimed to explore new method of aeration using oxygen enriched air performance on BOD reduction of palm oil wastewater was conducted. The oxygen enriched air was obtained from an Oxygen Enriched System (OES developed using asymmetric polysulfone hollow fiber membrane with composition consisting of PSF: 22%, DMAc: 31.8%, THF: 31.8%, EtOH: 14.4%. Palm oil wastewater samples were taken from facultative pond effluent. These samples were tested for its initial biochemical oxygen demand (BOD, total suspended solids (TSS, pH, conductivity, turbidity, dissolved oxygen (DO, suspended solids (SS, and total dissolved solids (TDS before being subjected to two modes of aeration system, that is diffused air and oxygen enriched air. These water quality concentrations were tested for every 20 minutes for two-hour period during the aeration process. Results of BOD, TSS, pH, conductivity, DO, SS and TDS concentrations against time of samples from the two modes of aeration were then compared. It was found that DO concentration achieved in oxygen enriched air aeration was better than aeration using diffused air system. Aeration using OES improve the DO concentration in the wastewater and thus improve the BOD reduction and also influence other physical characteristics of wastewater. This phenomenon indicates the advantage of using air with higher oxygen concentration for wastewater aeration instead of diffused air system.

Lysimeter experiments to determine the ability of soil to reduce concentrations of BOD, available P and inorganic N in dirty water.

Science.gov (United States)

Brookman, S K E; Chadwick; Retter, A R

2005-11-01

Lysimeter experiments were conducted to determine the ability of different soils to reduce levels of biochemical oxygen demand (BOD) and concentrations of molybdate reactive phosphorus (MRP) and ammonium-N (NH4(+)-N) in dirty water and the impact of applications on nitrate leaching. An additional experiment investigated the effect of dirty water components on leaching quality. This information is required to assess the potential risk of dirty water applications on polluting groundwater and to assess the use of such soils in the development of treatment systems for dirty water. Intact and disturbed soil lysimeters, 0.5 and 1m deep were constructed from four soils; a coarse free-draining sandy loam, a sandy loam over soft sandstone, a calcareous silty clay over chalk and a sandy loam over granite. For the coarse free-draining sandy loam, lysimeters were also constructed from disturbed soil with and without the addition of lime, to assess if this could increase phosphorus immobilisation. Levels of BOD and concentrations of MRP, NH4(+)-N and nitrate (NO3(-)-N) of leachates were measured following dirty water applications at 2 and 8 mm day(-1) under laboratory conditions. Under the daily 2mm application, all soils were effective at treating dirty water, reducing concentrations of BOD, MRP and NH4(+)- N by > or = 98% but NO3(-)-N concentrations increased up to 80 mg l(-1) from the 0.5 m deep lysimeters of the sandy loam over granite. Soils were less effective at reducing levels of BOD, MRP and NH4(+)- N at the 8 mm daily rate of application, with maximum NO3(-)-N concentrations of leachates of 200 mg l(-1) from disturbed soils.

Diurnal variations in wastewater characteristics at main out fall in Lahore

International Nuclear Information System (INIS)

Haider, H.; Ali, W.; Ali, W.

2012-01-01

Variations in the flow and pollutants concentrations during the day were monitored at the Main Out fall disposal station of the city of Lahore. The laboratory analysis of the wastewater samples collected at 2 hour interval on fifth and sixth May, 2009 for pH, temperature, alkalinity, hardness, Biochemical Oxygen Demand (BOD5), BOD5 Filtered, Total Kjeldahl Nitrogen (TKN), Ammonia Nitrogen (NH/sub 3/-N), chlorides, solids, turbidity, sulphates and nitrates were carried out. Average values and standard deviations were determined to assess the type of wastewater treatment. Correlation between BOD5 and BOD5 Filtered was developed through regression analysis. Diurnal variations in the Ultimate Biochemical Oxygen Demand (BODU) at the Main Out fall based on Carbonaceous Biochemical Oxygen Demand (CBODU) and Nitrogenous Biochemical Oxygen Demand (NBODU) are also estimated. The ratio between CBODU/NBODU ranges between 0.86 to 1.8 during a day at Main Out fall. This variation is primarily due to the large diurnal variation in CBODU values as a result of industrial activities in the study area. The BOD5/ TKN ratio varies between 3.3 and 6.9 and the calculated BODU (i.e., CBODU + NBODU) was found to be almost double of BOD5 during most part of the day primarily due to inclusion of NBOD. The study results reveal the importance of NBOD while designing the wastewater treatment facilities and implementing a water quality control strategy for the River Ravi. (author)

Incorporation of oxygen contribution by plant roots into classical dissolved oxygen deficit model for a subsurface flow treatment wetland.

Science.gov (United States)

Bezbaruah, Achintya N; Zhang, Tian C

2009-01-01

It has been long established that plants play major roles in a treatment wetland. However, the role of plants has not been incorporated into wetland models. This study tries to incorporate wetland plants into a biochemical oxygen demand (BOD) model so that the relative contributions of the aerobic and anaerobic processes to meeting BOD can be quantitatively determined. The classical dissolved oxygen (DO) deficit model has been modified to simulate the DO curve for a field subsurface flow constructed wetland (SFCW) treating municipal wastewater. Sensitivities of model parameters have been analyzed. Based on the model it is predicted that in the SFCW under study about 64% BOD are degraded through aerobic routes and 36% is degraded anaerobically. While not exhaustive, this preliminary work should serve as a pointer for further research in wetland model development and to determine the values of some of the parameters used in the modified DO deficit and associated BOD model. It should be noted that nitrogen cycle and effects of temperature have not been addressed in these models for simplicity of model formulation. This paper should be read with this caveat in mind.

Model development for prediction and mitigation of dissolved oxygen sags in the Athabasca River, Canada

Energy Technology Data Exchange (ETDEWEB)

Martin, Nancy, E-mail: nancy@ualberta.ca [Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB, Canada T6G 2W2 (Canada); McEachern, Preston [Tervita Corporation, AB (Canada); Yu, Tong; Zhu, David Z. [Department of Civil and Environmental Engineering, University of Alberta, Edmonton, AB, Canada T6G 2W2 (Canada)

2013-01-15

Northern rivers exposed to high biochemical oxygen demand (BOD) loads are prone to dissolved oxygen (DO) sags in winter due to re-aeration occurring within limited open water leads. Additionally, photosynthesis is reduced by decreased daylight hours, inability of solar radiation to pass through ice, and slower algal growth in winter. The low volumetric flow decreases point-source dilution while their travel time increases. The Athabasca River in Alberta, Canada, has experienced these sags which may affect the aquatic ecosystem. A water quality model for an 800 km reach of this river was customized, calibrated, and validated specifically for DO and the factors that determine its concentration. After validation, the model was used to assess the assimilative capacity of the river and mitigation measures that could be deployed. The model reproduced the surface elevation and water temperature for the seven years simulated with mean absolute errors of < 15 cm and < 0.9 °C respectively. The ice cover was adequately predicted for all seven winters, and the simulation of nutrients and phytoplankton primary productivity were satisfactory. The DO concentration was very sensitive to the sediment oxygen demand (SOD), which represented about 50% of the DO sink in winter. The DO calibration was improved by implementing an annual SOD based on the BOD load. The model was used to estimate the capacity of the river to assimilate BOD loads in order to maintain a DO concentration of 7 mg/L, which represents the chronic provincial guideline plus a buffer of 0.5 mg/L. The results revealed the maximum assimilative BOD load of 8.9 ton/day at average flow conditions, which is lower than the maximum permitted load. In addition, the model predicted a minimum assimilative flow of about 52 m{sup 3}/s at average BOD load. Climate change scenarios could increase the frequency of this low flow. A three-level warning-system is proposed to manage the BOD load proactively at different river

An evaluation of solutions to moment method of biochemical oxygen ...

African Journals Online (AJOL)

This paper evaluated selected solutions of moment method in respect to Biochemical Oxygen Demand (BOD) kinetics with the aim of ascertain error free solution. Domestic - institutional wastewaters were collected two - weekly for three months from waste - stabilization ponds in Obafemi Awolowo University, Ile - Ife.

A theoretical model for oxygen transport in skeletal muscle under conditions of high oxygen demand.

Science.gov (United States)

McGuire, B J; Secomb, T W

2001-11-01

Oxygen transport from capillaries to exercising skeletal muscle is studied by use of a Krogh-type cylinder model. The goal is to predict oxygen consumption under conditions of high demand, on the basis of a consideration of transport processes occurring at the microvascular level. Effects of the decline in oxygen content of blood flowing along capillaries, intravascular resistance to oxygen diffusion, and myoglobin-facilitated diffusion are included. Parameter values are based on human skeletal muscle. The dependence of oxygen consumption on oxygen demand, perfusion, and capillary density are examined. When demand is moderate, the tissue is well oxygenated and consumption is slightly less than demand. When demand is high, capillary oxygen content declines rapidly with axial distance and radial oxygen transport is limited by diffusion resistance within the capillary and the tissue. Under these conditions, much of the tissue is hypoxic, consumption is substantially less than demand, and consumption is strongly dependent on capillary density. Predicted consumption rates are comparable with experimentally observed maximal rates of oxygen consumption.

Artificial neural network modelling of biological oxygen demand in rivers at the national level with input selection based on Monte Carlo simulations.

Science.gov (United States)

Šiljić, Aleksandra; Antanasijević, Davor; Perić-Grujić, Aleksandra; Ristić, Mirjana; Pocajt, Viktor

2015-03-01

Biological oxygen demand (BOD) is the most significant water quality parameter and indicates water pollution with respect to the present biodegradable organic matter content. European countries are therefore obliged to report annual BOD values to Eurostat; however, BOD data at the national level is only available for 28 of 35 listed European countries for the period prior to 2008, among which 46% of data is missing. This paper describes the development of an artificial neural network model for the forecasting of annual BOD values at the national level, using widely available sustainability and economical/industrial parameters as inputs. The initial general regression neural network (GRNN) model was trained, validated and tested utilizing 20 inputs. The number of inputs was reduced to 15 using the Monte Carlo simulation technique as the input selection method. The best results were achieved with the GRNN model utilizing 25% less inputs than the initial model and a comparison with a multiple linear regression model trained and tested using the same input variables using multiple statistical performance indicators confirmed the advantage of the GRNN model. Sensitivity analysis has shown that inputs with the greatest effect on the GRNN model were (in descending order) precipitation, rural population with access to improved water sources, treatment capacity of wastewater treatment plants (urban) and treatment of municipal waste, with the last two having an equal effect. Finally, it was concluded that the developed GRNN model can be useful as a tool to support the decision-making process on sustainable development at a regional, national and international level.

Determination of Biological Oxygen Demand Rate Constant and ...

African Journals Online (AJOL)

Determination of Biological Oxygen Demand Rate Constant and Ultimate Biological Oxygen Demand for Liquid Waste Generated from Student Cafeteria at Jimma University: A Tool for Development of Scientific Criteria to Protect Aquatic Health in the Region.

Huge supply/demand increases seen in oxygenate forecasts

International Nuclear Information System (INIS)

Rhoades, A.K.

1992-01-01

Industry originally projected that oxygenate supply would not be able to meet the demand created by U.S. oxygenated and reformulated gasoline mandates. This paper reports that those projections have been reserved in two recent industry reports - one from Chemical Market Associates Inc. (CMAI) and one from Pace Consultants Inc. Pace's report, by Paulo Nery and Nathan Sims, predicts gasoline and oxygenates demand, and examines the role ethanol may play in changing those values. CMAI's report estimates captive supply and demand of butylenes and oxygenates. Oxygenates are entering the domestic gasoline market this winter as a result of the 1990 U.S. Clean Air Act Amendments. Methyl tertiary butyl ether (MTBE) is the most important oxygenate, although ethanol, ethyl tertiary butyl ether (ETBE), and tertiary amyl methyl ether (TAME) are gathering market strength. Ethanol's strength is derived from President Bush's ruling granting a waiver to reformulated gasoline containing ethanol. This waiver allows ethanol blends to have a vapor pressure 1 psi higher than other types of gasoline

Correlation of COD and BOD of domestic wastewater with the power output of bioreactor

Energy Technology Data Exchange (ETDEWEB)

Khan, A M; Ataullah,; Shaheen, A; Ahmad, I; Malik, F; Shahid, H A [Federal Urdu University of Arts, Science and Technology, Gulshan-e-Iqbal Campus, University Road, Karachi-75300 (Pakistan). Research Laboratory of Bioenergy, Department of Chemistry

2011-04-15

This research article deals with the studies on the development of the correlation of COD, BOD, and BOD/sub 5/ of domestic wastewater (DWW), and fermented domestic wastewater (FDWW) with the power output of the microbial fuel cell (MFC). The fermentation of DWW was carried out with yeast (Saccharomyces cerevisiae), and yogurt bacteria (Streptococcus lactis) to produce biohydrogen which was converted to the electrical energy through the development of microbial fuel cell (MFC). The values of COD, BOD, and BOD/sub 5/ for yogurt fermented domestic wastewater (Yogurt-FDWW) were found to be greater than the values of yeast fermented domestic wastewater (Yeast-FDWW). The power output of DWW and FDWW was increased with the increase in COD, BOD and BOD/sub 5/ values. The main objective of this article is to develop the renewable alternative of fossil fuels which are the major cause of global warming and global pollution. (author)

Correlation of COD and BOD of domestic wastewater with the power output of bioreactor

International Nuclear Information System (INIS)

Khan, A.M.; Ataullah; Shaheen, A.; Ahmad, I.; Malik, F.; Shahid, H.A.

2011-01-01

This research article deals with the studies on the development of the correlation of COD, BOD, and BOD/sub 5/ of domestic wastewater (DWW), and fermented domestic wastewater (FDWW) with the power output of the microbial fuel cell (MFC). The fermentation of DWW was carried out with yeast (Saccharomyces cerevisiae), and yogurt bacteria (Streptococcus lactis) to produce biohydrogen which was converted to the electrical energy through the development of microbial fuel cell (MFC). The values of COD, BOD, and BOD/sub 5/ for yogurt fermented domestic wastewater (Yogurt-FDWW) were found to be greater than the values of yeast fermented domestic wastewater (Yeast-FDWW). The power output of DWW and FDWW was increased with the increase in COD, BOD and BOD/sub 5/ values. The main objective of this article is to develop the renewable alternative of fossil fuels which are the major cause of global warming and global pollution. (author)

Estimates of Nitrogen, Phosphorus, Biochemical Oxygen Demand, and Fecal Coliforms Entering the Environment Due to Inadequate Sanitation Treatment Technologies in 108 Low and Middle Income Countries.

Science.gov (United States)

Fuhrmeister, Erica R; Schwab, Kellogg J; Julian, Timothy R

2015-10-06

Understanding the excretion and treatment of human waste (feces and urine) in low and middle income countries (LMICs) is necessary to design appropriate waste management strategies. However, excretion and treatment are often difficult to quantify due to decentralization of excreta management. We address this gap by developing a mechanistic, stochastic model to characterize phosphorus, nitrogen, biochemical oxygen demand (BOD), and fecal coliform pollution from human excreta for 108 LMICs. The model estimates excretion and treatment given three scenarios: (1) use of existing sanitation systems, (2) use of World Health Organization-defined "improved sanitation", and (3) use of best available technologies. Our model estimates that more than 10(9) kg/yr each of phosphorus, nitrogen and BOD are produced. Of this, 22(19-27)%, 11(7-15)%, 17(10-23)%, and 35 (23-47)% (mean and 95% range) BOD, nitrogen, phosphorus, and fecal coliforms, respectively, are removed by existing sanitation systems. Our model estimates that upgrading to "improved sanitation" increases mean removal slightly to between 17 and 53%. Under the best available technology scenario, only approximately 60-80% of pollutants are treated. To reduce impact of nutrient and microbial pollution on human and environmental health, improvements in both access to adequate sanitation and sanitation treatment efficiency are needed.

Enhancing Signal Output and Avoiding BOD/Toxicity Combined Shock Interference by Operating a Microbial Fuel Cell Sensor with an Optimized Background Concentration of Organic Matter

Directory of Open Access Journals (Sweden)

Yong Jiang

2016-08-01

Full Text Available In the monitoring of pollutants in an aquatic environment, it is important to preserve water quality safety. Among the available analysis methods, the microbial fuel cell (MFC sensor has recently been used as a sustainable and on-line electrochemical microbial biosensor for biochemical oxygen demand (BOD and toxicity, respectively. However, the effect of the background organic matter concentration on toxicity monitoring when using an MFC sensor is not clear and there is no effective strategy available to avoid the signal interference by the combined shock of BOD and toxicity. Thus, the signal interference by the combined shock of BOD and toxicity was systematically studied in this experiment. The background organic matter concentration was optimized in this study and it should be fixed at a high level of oversaturation for maximizing the signal output when the current change (ΔI is selected to correlate with the concentration of a toxic agent. When the inhibition ratio (IR is selected, on the other hand, it should be fixed as low as possible near the detection limit for maximizing the signal output. At least two MFC sensors operated with high and low organic matter concentrations and a response chart generated from pre-experiment data were both required to make qualitative distinctions of the four types of combined shock caused by a sudden change in BOD and toxicity.

In situ microbial fuel cell-based biosensor for organic carbon

DEFF Research Database (Denmark)

de Jesus dos Santos Peixoto, Luciana; Min, Booki; Martins, Gilberto

2011-01-01

The biological oxygen demand (BOD) may be the most used test to assess the amount of pollutant organic matter in water; however, it is time and labor consuming, and is done ex-situ. A BOD biosensor based on the microbial fuel cell principle was tested for online and in situ monitoring of biodegra......The biological oxygen demand (BOD) may be the most used test to assess the amount of pollutant organic matter in water; however, it is time and labor consuming, and is done ex-situ. A BOD biosensor based on the microbial fuel cell principle was tested for online and in situ monitoring...... of biodegradable organic content of domestic wastewater. A stable current density of 282±23mA/m2 was obtained with domestic wastewater containing a BOD5 of 317±15mg O2/L at 22±2°C, 1.53±0.04mS/cm and pH 6.9±0.1. The current density showed a linear relationship with BOD5 concentration ranging from 17±0.5mg O2/L...

Right ventricular oxygen supply/demand balance in exercising dogs.

Science.gov (United States)

Hart, B J; Bian, X; Gwirtz, P A; Setty, S; Downey, H F

2001-08-01

This is the first investigation of right ventricular (RV) myocardial oxygen supply/demand balance in a conscious animal. A novel technique developed in our laboratory was used to collect right coronary (RC) venous blood samples from seven instrumented, conscious dogs at rest and during graded treadmill exercise. Contributions of the RV oxygen extraction reserve and the RC flow reserve to exercise-induced increases in RV oxygen demand were measured. Strenuous exercise caused a 269% increase in RV oxygen consumption. Expanded arteriovenous oxygen content difference (A-V(Delta)O2) provided 58% of this increase in oxygen demand, and increased RC blood flow (RCBF) provided 42%. At less strenuous exercise, expanded A-V(Delta)O2 provided 60-80% of the required oxygen, and increases in RCBF were small and driven by increased aortic pressure. RC resistance fell only at strenuous exercise after the extraction reserve had been mobilized. Thus RC resistance was unaffected by large decreases in RC venous PO2 until an apparent threshold at 20 mmHg was reached. Comparisons of RV findings with published left ventricular data from exercising dogs demonstrated that increased O2 demand of the left ventricle is met primarily by increasing coronary flow, whereas increased O2 extraction makes a greater contribution to RV O2 supply.

Evaluation of organic matter concentration in winery wastewater: a case study from Australia.

Science.gov (United States)

Quayle, Wendy C; Fattore, Alison; Zandona, Roy; Christen, Evan W; Arienzo, Michele

2009-01-01

The 5-day biological oxygen demand (BOD(5)) remains a key indicator for proof of compliance with environmental regulators in the monitoring and management of winery effluent. Inter-conversion factors from alternative tests that are more rapid, accurate and simpler to perform have been determined that allow prediction of BOD(5) in winery wastewaters, generally, and at different stages of production and treatment. Mean values obtained from this dataset offer rule of thumb inter-conversion factors: BOD(5) = 0.7 Chemical Oxygen Demand (COD), BOD(5) = 2.3 Total Organic Carbon (TOC) and BOD(5) = 2.7 Dissolved Organic Carbon (DOC). Specific predictive linear relationships are also provided. Out of the relationships between BOD(5) vs COD, TOC and DOC, in winery wastewater, irrespective of vintage or non-vintage production periods and stage of treatment, TOC offered the most reliable prediction of BOD(5). Ethanol, glucose and fructose were evaluated in untreated wastewater as predictors of BOD(5) due to their high specificity in winery effluent. A significant relationship was determined between BOD(5) and (ethanol + glucose + fructose; R(2) = 0.64, n = 19; pwinery effluents when using a commercially available mercury free test kit compared with using a traditional COD test kit that contained mercury. This suggests that mercury free COD test kits could be used by the wine industry for organic pollution assessment with associated reductions to user and environmental risk, as well as reducing the costs of kit waste disposal.

Hollow-fiber membrane bioreactor for the treatment of high-strength landfill leachate

KAUST Repository

Rizkallah, Marwan; El-Fadel, Mutasem E.; Saikaly, Pascal; Ayoub, George M.; Darwiche, Nadine D.; Hashisho, Jihan

2013-01-01

-fiber MBR. For this purpose, a laboratory-scale MBR was constructed and operated to treat leachate with a chemical oxygen demand (COD) of 9000-11,000 mg/l, a 5-day biochemical oxygen demand (BOD5) of 4000-6,000 mg/l, volatile suspended solids (VSS) of 300

Chemical oxygen demand (cod) attenuation of methyl red in water ...

African Journals Online (AJOL)

Chemical oxygen demand (cod) attenuation of methyl red in water using biocarbons obtained from Nipa palm leaves. ... eco-friendly and locally accessible biocarbon for mitigation of organic contaminants in water. Keywords: Chemical oxygen demand, biocarbon, methyl red, biodegradation, bioremediation, Nipa palm ...

Characteristic of leachate at Alor Pongsu Landfill Site, Perak, Malaysia: A comparative study

Science.gov (United States)

Nor Farhana Zakaria, Siti; Aziz, Hamidi Abdul

2018-04-01

Leachate is a harmful by product generated from the landfill site. Leachate contains a high concentration of pollutant which can cause serious pollution to environmental. In this study, characteristics of leachate in Alor Pongsu Landfill Site (APLS) were monitored and analyzed according to the Standard Methods for the Examination of Water and Wastewater (2005). Composition in leachate at APLS was monitored for one year starting from January 2015 until January 2016. Nine parameters were monitored including color, chemical oxygen demand (COD), biological oxygen demand (BOD5), ammoniacal nitrogen (NH3-N), biodegradability ratio (BOD5/COD), temperature, dissolved oxygen (DO), total dissolved solid (TDS) and pH. Based on the analysis, Alor Pongsu Landfill leachate was categorized as stabilized landfill leachate by referring to the BOD5/COD < 0.1. Comparison with allowable discharge limits for leachate shows that most of parameters exceeded the standard discharge limitation. Thus, proper treatment is needed before leachate can be discharged to the environment.

Stream Macroinvertebrate Occurrence along Gradients in Organic Pollution and Eutrophication

DEFF Research Database (Denmark)

Friberg, Nikolai; Skriver, Jens; Larsen, Søren Erik

2010-01-01

We analysed a large number of concurrent samples of macroinvertebrate communities and chemical indicators of eutrophication and organic pollution [total-P, total-N, NH4-N, biological oxygen demand (BOD5)] from 594 Danish stream sites. Samples were taken over an 11-year time span as part of the Da......We analysed a large number of concurrent samples of macroinvertebrate communities and chemical indicators of eutrophication and organic pollution [total-P, total-N, NH4-N, biological oxygen demand (BOD5)] from 594 Danish stream sites. Samples were taken over an 11-year time span as part...

Construction of Microbial-based Biosensor to Measure BOD of Industrial Wastewaters

Directory of Open Access Journals (Sweden)

Behnam Mahdavi

2014-04-01

Full Text Available In this study a cell-based biosensor for measurement of BOD was designed and developed. Activated sludge collected from wastewater treatment plant of Shahinshahr was used as biological receptor and a Clark cell was used as transducer. According to the results obtained from the sensor calibration, a linear relationship between the current changes and glucose-glutamic acid (GAA standard concentrations up to 50 mg/L was observed. The BOD values of different industrial wastewaters, inlet and outlet of treatment plant of Ardineh Company (Isfahan, and also  inlet and outlet of domestic wastewater treatment plant of Shahinshahr, and outlet of treatment plant of Pegah Company (Isfahan were measured using this biosensor. Comparison of the results of this biosensor and the results of the standard BOD test (BOD5 showed that the mean percentage error measured by the sensor was +29.6%. The results concerning the stability of the designed biosensor showed a stability time of 3 days for the response of biosensor.

Nutrient regeneration and oxygen demand in Bering Sea continental shelf sediments

Science.gov (United States)

Rowe, Gilbert T.; Phoel, William C.

1992-04-01

Measurements of seabed oxygen demand and nutrient regeneration were made on continental shelf sediments in the southeast Bering Sea from 1 to 15 June 1981. The mean seabed oxygen demand was relatively modest (267 μM O 2 m -2 h -1), equivalent to a utilization of 60 mg organic carbon m -2 day -1. The seasonal build up of ammonium over the mid-shelf domain was generated at least in part by the bottom biota, as previously suggested ( WHITLEDGEet al., 1986 , Continental Shelf Research, 5, 109-132), but on the outer shelf nitrate replaced ammonium as the dominant inorganic nitrogen compound that was regenerated from the sediments. Comparison of oxygen consumption with the organic matter in sedimenting particulate matter (sampled with sediment traps) could imply that benthic processes were not accounting for the fate of considerable quantities of organic matter. Benthic oxygen demand rates, however, probably lag behind the input of the spring bloom to the bottom, thus extending the remineralization process out over time. Consumption by small microheterotrophs in the water column was also a likely sink, although shelf export and advective transport north were possible as well. Estimated nitrification rates in surface sediments could account for only a small fraction of the abrupt increase in nitrate observed in the water column over the shelf just prior to the spring bloom.

Tissue oxygen demand in regulation of the behavior of the cells in the vasculature.

Science.gov (United States)

Barvitenko, Nadezhda N; Aslam, Muhammad; Filosa, Jessica; Matteucci, Elena; Nikinmaa, Mikko; Pantaleo, Antonella; Saldanha, Carlota; Baskurt, Oguz K

2013-08-01

The control of arteriolar diameters in microvasculature has been in the focus of studies on mechanisms matching oxygen demand and supply at the tissue level. Functionally, important vascular elements include EC, VSMC, and RBC. Integration of these different cell types into functional units aimed at matching tissue oxygen supply with tissue oxygen demand is only achieved when all these cells can respond to the signals of tissue oxygen demand. Many vasoactive agents that serve as signals of tissue oxygen demand have their receptors on all these types of cells (VSMC, EC, and RBC) implying that there can be a coordinated regulation of their behavior by the tissue oxygen demand. Such functions of RBC as oxygen carrying by Hb, rheology, and release of vasoactive agents are considered. Several common extra- and intracellular signaling pathways that link tissue oxygen demand with control of VSMC contractility, EC permeability, and RBC functioning are discussed. © 2013 John Wiley & Sons Ltd.

Chapter A7. Section 7.0. Five-Day Biochemical Oxygen Demand

Science.gov (United States)

Delzer, Gregory C.; McKenzie, Stuart W.

1999-01-01

The presence of a sufficient concentration of dissolved oxygen is critical to maintaining the aquatic life and aesthetic quality of streams and lakes. Determinng how organic matter affects the concentration of dissolved oxygen (DO) in a stream or lake is integral to water-quality management. The decay of organic matter in water is measured as biochemical or chemical oxygen demand. This report describes the field protocols used by U.S. Geological Survey (USGS) personnel to determine the five-day test for biochemical oxygen demand.

The Metropolis-Hastings algorithm, a handy tool for the practice of environmental model estimation : illustration with biochemical oxygen demand data

Directory of Open Access Journals (Sweden)

Franck Torre

2001-02-01

Full Text Available Environmental scientists often face situations where: (i stimulus-response relationships are non-linear; (ii data are rare or imprecise; (iii facts are uncertain and stimulus-responses relationships are questionable. In this paper, we focus on the first two points. A powerful and easy-to-use statistical method, the Metropolis-Hastings algorithm, allows the quantification of the uncertainty attached to any model response. This stochastic simulation technique is able to reproduce the statistical joint distribution of the whole parameter set of any model. The Metropolis-Hastings algorithm is described and illustrated on a typical environmental model: the biochemical oxygen demand (BOD. The aim is to provide a helpful guideline for further, and ultimately more complex, models. As a first illustration, the MH-method is also applied to a simple regression example to demonstrate to the practitioner the ability of the algorithm to produce valid results.

The supply and demand for pollution control: Evidence from wastewater treatment

Science.gov (United States)

McConnell, V.D.; Schwarz, G.E.

1992-01-01

This paper analyzes the determination of pollution control from wastewater treatment plants as an economic decision facing local or regional regulators. Pollution control is measured by plant design effluent concentration levels and is fully endogenous in a supply- and-demand model of treatment choice. On the supply side, plant costs are a function of the design treatment level of the plant, and on the demand side, treatment level is a function of both the costs of control and the regional or regulatory preferences for control. We find evidence that the economic model of effluent choice by local regulators has a good deal of explanatory power. We find evidence that wastewater treatment plant removal of biological oxygen demand (BOD) is sensitive to many local factors including the size of the treatment plant, the flow rate of the receiving water, the population density of the surrounding area, regional growth, state sensitivity to environmental issues, state income, and the extent to which the damages from pollution fall on other states. We find strong evidence that regulators are sensitive to capital costs in determining the design level of BOD effluent reduction at a plant. Thus, proposed reductions in federal subsidies for wastewater treatment plant construction are likely to have significant adverse effects on water quality. ?? 1992.

Measurement of biological oxygen demand sandy beaches

African Journals Online (AJOL)

Measurements of biological oxygen demand in a sandy beach using conventional .... counting the cells present in a sample of aged seawater and comparing this with .... This activity peaked at 71 % above the undisturbed level after 16 hours.

Efeito da concentração inicial de oxigênio no coeficiente de aeração para experimentos de DBO de longo prazo - DOI: 10.4025/actascibiolsci.v25i2.1976 Effect of initial concentration of dissolved oxygen in aeration coefficient for long-term BOD experiments- DOI: 10.4025/actascibiolsci.v25i2.1976

Directory of Open Access Journals (Sweden)

Marcela Bianchessi da Cunha Santino

2003-04-01

Full Text Available Incubações de demanda bioquímica de oxigênio (DBO de longo prazo foram realizadas para determinar o coeficiente de aeração proveniente de experimentos de consumo de oxigênio. Os frascos de DBO foram preparados com água destilada e incubados no escuro e sob temperatura controlada (19,4ºC. Os frascos foram submetidos a dois tratamentos que foram baseados na concentração inicial de oxigênio dissolvido (OD: Tratamento 1 = 1,43mg L-1 e Tratamento 2 = 7,67mg L-1. As concentrações de OD foram determinadas com oxímetro durante 52 dias. Os resultados foram ajustados a um modelo cinético de primeira ordem. Os frascos de DBO apresentaram um incremento nas concentrações de OD para ambos os tratamentos e o coeficiente de aeração (ka foi de 0,065 dia-1. Os ajustes apontam dispersão nos valores de ka e a concentração inicial de OD nos frascos de DBO não interferiu no processo de aeração sendo um processo aleatórioLong-term incubations of biochemical oxygen demand (BOD were performed to determine the aeration coefficient derived from oxygen uptake experiments. The BOD bottles were prepared with distilled water and the incubation occurred in the dark, under controlled temperature (19.4ºC. The bottles were submitted to two different treatments based on the initial dissolved oxygen (DO concentrations (Treatment 1: 1.43mg L-1 and Treatment 2: 7.67mg L-1. The DO concentrations were measured with an OD meter during 52 days. The results were fitted to a first-order kinetics model. The BOD bottles showed an increase in DO concentration for both treatments and the mean aeration coefficient (ka was 0.065 a day-1. The fittings pointed to some dispersion in the ka values, and the initial concentration of DO in the BOD bottles does not interfere in the aeration process, being a random process

Hollow-fiber membrane bioreactor for the treatment of high-strength landfill leachate

KAUST Repository

Rizkallah, Marwan

2013-07-15

Performance assessment of membrane bioreactor (MBR) technology for the treatability of high-strength landfill leachate is relatively limited or lacking. This study examines the feasibility of treating high-strength landfill leachate using a hollow-fiber MBR. For this purpose, a laboratory-scale MBR was constructed and operated to treat leachate with a chemical oxygen demand (COD) of 9000-11,000 mg/l, a 5-day biochemical oxygen demand (BOD5) of 4000-6,000 mg/l, volatile suspended solids (VSS) of 300-500 mg/l, total nitrogen (TN) of 2000-6000 mg/l, and an ammonia-nitrogen (NH3-N) of 1800-4000 mg/l. VSS was used with the BOD and COD data to simulate the biological activity in the activated sludge. Removal efficiencies > 95-99% for BOD5, VSS, TN and NH3-N were attained. The coupled experimental and simulation results contribute in filling a gap in managing high-strength landfill leachate and providing guidelines for corresponding MBR application. © The Author(s) 2013.

Study of the degradation performance (TOC, BOD, and toxicity) of bisphenol A by the photo-Fenton process.

Science.gov (United States)

Pérez-Moya, M; Kaisto, T; Navarro, M; Del Valle, L J

2017-03-01

Degradation of bisphenol A (BPA, 0.5 L, 30 mg L -1 ) was studied by photo-Fenton treatment, while Fenton reagents were variables. The efficiency of the degradation process was evaluated by the reduction of total organic carbon (TOC), the biochemical oxygen demand (BOD), and toxicity. For toxicity analysis, bacterial methods were found infeasible, but the in vitro assay of VERO cells culture was successfully applied. Experiments according to a 2 2 design of experiments (DOE) with star points and three center points for statistical validity allowed selecting those process conditions (Fe(II) and H 2 O 2 load) that maximized the process performance. Photo-Fenton process effectively eliminated BPA and partly degraded its by-products (residual TOC TOC = 92 %) was attained. Toxicity was also detected to 50 % of cellular mortality even at long reaction times. However, 40.25 mg L -1 of H 2 O 2 decreased residual TOC to 70 % while cell mortality decreased down to 25 %. With more H 2 O 2 , the residual TOC decreased down to 15 % but cell mortality remained within the 20-25 % level. Photo-Fenton increased the biodegradability and reduced the toxicity of the studied sample.

Oxidant reduction and biodegradability improvement of paper mill effluent by irradiation

International Nuclear Information System (INIS)

Tiezheng Wang; Waite, T.D.; Kurucz, C.

1994-01-01

Paper mill bleach processing wastewaters represent a large input of hazardous compounds to the environment and these compounds are usually non-biodegradable. A preliminary study using a 5000 Ci 60 Co gamma radiation source as a surrogate for electron beam irradiation, potentially an emerging technology for wastewater treatment, to treat a paper mill bleach effluent showed that for an absorbed dose of 800 krads, chemical oxygen demand (COD) was reduced by 13.5% and 5 day biochemical oxygen demand (BOD 5 ) was increased 58.6%. These changes altered the value of COD/BOD 5 from 14 to 5. For the same dose, the absorbable organic halogen (AOX) was reduced 76.2%. These results suggested the possibility of using the electron beam process to detoxify paper mill effluent thereby generating a more biodegradable wastewater. (author)

Onsite Greywater Treatment using Pilot Scale Technology

Directory of Open Access Journals (Sweden)

Manzoor-ul-Haq Rajput

2015-04-01

Full Text Available The GROW Technology for greywater treatment was installed at the MUET (Mehran University of Engineering & Technology, hostel and run under continuous flow conditions with hydraulic loading rate of 0.15m.d-1. The monitoring and analysis of influent and effluent water were carried out during January-December, 2010. Local plants species such as water hyacinth, Pennywort (duck weed, Mint and Cattail were used in the GROW rig as a mixed mode. Coarse Gravels were filled in the troughs as a medium. The collected samples were analyzed for BOD5 (Biochemical Oxygen Demand, COD (Chemical Oxygen Demand, TSS (Total Suspended Solids, pH, and DO (Dissolved Oxygen. Removal efficiencies of BOD5, COD and TSS were calculated as 83.0,69.0 and 84.0% respectively. DO was found increased from 0.6-3.5 mg.dm-3 while pH was observed between 6.5-7.8

Onsite greywater treatment using pilot scale grow technology

International Nuclear Information System (INIS)

Rajput, M.U.

2015-01-01

The GROW Technology for greywater treatment was installed at the MUET (Mehran University of Engineering and Technology), hostel and run under continuous flow conditions with hydraulic loading rate of 0.15m.d-1. The monitoring and analysis of influent and effluent water were carried out during January-December, 2010. Local plants species such as water hyacinth, Pennywort (duck weed), Mint and Cattail were used in the GROW rig as a mixed mode. Coarse Gravels were filled in the troughs as a medium. The collected samples were analyzed for BOD5 (Biochemical Oxygen Demand), COD (Chemical Oxygen Demand), TSS (Total Suspended Solids), pH, and DO (Dissolved Oxygen). Removal efficiencies of BOD5, COD and TSS were calculated as 83.0,69.0 and 84.0% respectively. DO was found increased from 0.6-3.5 mg.dm-3 while pH was observed between 6.5-7.8. (author)

Reduction Colour and BOD of Textile Waste by Carbon-TiO2

International Nuclear Information System (INIS)

Budi Setiawan; Rosyidin; Nurimaniwathy

2007-01-01

The Granule Forming of Carbon adsorbent has been done with 5, 10, 15% of TiO 2 using the variation of adhesive materials on 110, 130, and 150 °C with diameter of 0.5 and 1 cm. The adsorbent materials was used to media of color levels absorption and BOD level on textile waste product by using stirring methods. The variation of stirring 20, 40 and 60 minutes. The result showed that the best materials condition and process were fox glue on 110 °C, stirring time at 60 minutes at 15% TiO 2 , which potent to adsorb colours level 29.608% and BOD level 66.157%. (author)

A comparative study of technologies for the continuous measurements of the biochemical demand for oxygen and toxicity of water; Estudio comparativo de tecnologias de medicion en continuo de la demanda bioquimica de oxigeno y de la toxicidad en aguas

Energy Technology Data Exchange (ETDEWEB)

Diez-Caballero Arnau, T.; Rodriguez Albalat, G.; Rosa de la Garcia, S.; Jimenez Bono, M.; Millan Navarro, C.; prats, R.; Serramia, A.; Miguel, S. de

2002-07-01

The Prevention and Integrated Control of Contamination Act (Ley de Prevencion y control Integrado de la Contaminacion) was passed by the Spanish parliament on 13 June. the basic purpose of this law is to prevent, reduce and control contamination of the atmosphere, water and soil caused by the most contaminating industrial activities. Public sector bodies and private companies in Spanish have been invited by the European Union to adopt new technologies in their production processes with a view to cutting down emissions, minimising or re-using waste, and pre-treating or purifying effluents. I t is therefore extremely appropriate to make available information on new tools of analysis that allow users to take preventive measures to reduce the impact their activity may have on the environment. A fundamental parameter in monitoring water is the Biological Demand for Oxygen (BOD). Various different chemical, physical and biological techniques have been developed to solve the problem of continuously monitoring the BOD and toxicity of water. This study carried out a comparative analysis of these techniques, describing the advantages and disadvantages of applying them to water quality control. At the present time it can be said that the BOD microbiosensor. Multisens 304 is the best available technology for monitoring this parameter. The articles tells us why. (Author) 8 refs.

[Comparison of ciliate diversity in biodisc reactors which purify industrial wastewater].

Science.gov (United States)

Luna-Pabello, V M; Durán De Bazúa, C; Aladro-Lubel, M A

1995-01-01

The comparative study of the ciliate populations present in rotating biological reactors (biodiscs reactors) of 20 l working volume, treating three different wastewaters is the aim of this project. Wastewaters chosen were those of a maize mill, of a sugarcane/ethyl alcohol plant, and of a recycled paper mill. Its dissolved organic contents, measured as soluble chemical oxygen demand (COD) and five-day biochemical oxygen demand (BOD5), were 2040 mg COD/l and 585 mg BOD5/l for maize mill effluents (nejayote), 2000 mg COD/l and 640 mg BOD5/l for sugarcane/ethanol effluents (vinasses), and 960 mg COD/l and 120 mg BOD5/l for whitewaters of the paper industry. Results obtained indicate that ciliate proliferate in all chambers of reactors treating these wastewaters. The ciliates were more abundant in vinasses, followed by nejayote, and then whitewaters. Among protozoa, ciliates were present as follows: 19 species in total. Three of them were common for the three systems. Free swimming ciliates were in higher proportion than pedunculated ones. Its diversity was higher for the whitewaters system, next for nejayote, and the lesser, for vinasses, corroborating the fact that less polluted waters have higher organisms' diversity.

Application of Electrocoagulation Process for Dairy Wastewater Treatment

Directory of Open Access Journals (Sweden)

Edris Bazrafshan

2013-01-01

Full Text Available Dairy industry wastewater is characterized by high biochemical oxygen demand (BOD5, chemical oxygen demand (COD, and other pollution load. The purpose of this study was to investigate the effects of the operating parameters such as applied voltage, number of electrodes, and reaction time on a real dairy wastewater in the electrocoagulation process. For this purpose, aluminum electrodes were used in the presence of potassium chloride as electrolytes. It has been shown that the removal efficiency of COD, BOD5, and TSS increased with increasing the applied voltage and the reaction time. The results indicate that electrocoagulation is efficient and able to achieve 98.84% COD removal, 97.95% BOD5 removal, 97.75% TSS removal, and >99.9% bacterial indicators at 60 V during 60 min. The experiments demonstrated the effectiveness of electrocoagulation techniques for the treatment of dairy wastewaters. Finally, the results demonstrated the technical feasibility of electrocoagulation process using aluminum electrodes as a reliable technique for removal of pollutants from dairy wastewaters.

Correlating Biochemical and Chemical Oxygen Demand of Effluents

African Journals Online (AJOL)

F. K. Attiogbe1, Mary Glover-Amengor2 and K. T. Nyadziehe3

There is also a slaughterhouse for animals (Sarfo-Afriyie, 1999). ... day period of the BOD test, the bacteria oxidized mainly the soluble organic ..... characteristics of the waste (effluent) not being constant (http://www.hach.com), and this is.

Application of H2O and UV/H2O2 processes for enhancing the biodegradability of reactive black 5 dye.

Science.gov (United States)

Kalpana, S Divya; Kalyanaraman, Chitra; Gandhi, N Nagendra

2011-07-01

Leather processing is a traditional activity in India during which many organic and inorganic chemicals are added while part of it is absorbed by the leather, the remaining chemicals are discharged along with the effluent. The effluent contains both easily biodegradable and not easily biodegradable synthetic organics like dyes, syntans. Easily biodegradable organics are removed in the existing biological treatment units whereas synthetic organics present in the wastewater are mostly adsorbed over the microbes. As the tannery effluent contains complex chemicals, it is difficult to ascertain the degradation of specific pollutants. To determine the increase in the biodegradability, one of the complex and synthetic organic chemical like dye used in the tanning operation was selected for Advanced Oxidation Process (AOPs) treatment for cleaving complex organics and its subsequent treatment in aerobic process. In the present study, Reactive Black 5 Dye used in the tanning operation was selected for Hydrogen Peroxide (H2O2) and UV/H2O2 pre-treatment for different operating conditions like pH, contact time and different volume of H2O2. A comparison was made between the untreated, Hydrogen Peroxide (H2O2) and UV/H2O2 treated effluent in order to ascertain the influence of AOP on the improvement of biodegradability of effluent. An increase in the BOD5/COD ratio from 0.21 to 0.435 was achieved in the UV/H2O2 pre-treatment process. This pre-treated effluent was further subjected to aerobic process. Biochemical Oxygen Demand (BOD5) and Chemical Oxygen Demand (COD) removal efficiency of the UV/H2O2 pre-treated dye solution in the aerobic process was found to be 86.39% and 77.82% when compared to 52.43% of BOD5 and 51.55% of COD removal efficiency without any pre-treatment. Hence from these results, to increase the biodegradability of Reactive Black 5 dye pre-treatment methods like H2O2 and UV/H2O2 can be used prior to biological treatment process.

Evaluation of selected wetland plants for removal of chromium from ...

African Journals Online (AJOL)

user

demand (COD), biochemical oxygen demand (BOD) and nitrogen under a 5 day hydraulic retention time were analyzed based on HACH manual. The Cr in the plant tissue was analyzed through .... measured for five days of hydraulic retention time (HRT) using a stopwatch and measuring cylinder (Figure 1). The wastewater ...

Modification of SWAT model for simulation of organic matter in Korean watersheds.

Science.gov (United States)

Jang, Jae-Ho; Jung, Kwang-Wook; Gyeong Yoon, Chun

2012-01-01

The focus of water quality modeling of Korean streams needs to be shifted from dissolved oxygen to algae or organic matter. In particular, the structure of water quality models should be modified to simulate the biochemical oxygen demand (BOD), which is a key factor in calculating total maximum daily loads (TMDLs) in Korea, using 5-day BOD determined in the laboratory (Bottle BOD(5)). Considering the limitations in simulating organic matter under domestic conditions, we attempted to model total organic carbon (TOC) as well as BOD by using a watershed model. For this purpose, the Soil and Water Assessment Tool (SWAT) model was modified and extended to achieve better correspondence between the measured and simulated BOD and TOC concentrations. For simulated BOD in the period 2004-2008, the Nash-Sutcliffe model efficiency coefficient increased from a value of -2.54 to 0.61. Another indicator of organic matter, namely, the simulated TOC concentration showed that the modified SWAT adequately reflected the observed values. The improved model can be used to predict organic matter and hence, may be a potential decision-making tool for TMDLs. However, it needs further testing for longer simulation periods and other catchments.

Sediment oxygen demand of wetlands in the oil sands region of north-eastern Alberta

International Nuclear Information System (INIS)

Slama, C.; Ciborowski, J.J.; Gardner Costa, J.

2009-01-01

Reclaimed land in the Alberta oil sands mining area contains both reference and oil sands process-affected wetlands constructed using varying sediment compositions. The sediments derived from oil sands process materials (OSPM) may alter the biochemical reactions that take place and affect the sediment oxygen demand (SOD), which is a key factor that contributes to oxygen depletion. This presentation reported on a study in which SOD was measured in a suite of constructed wetlands of different ages, with or without OSPM and topsoil. The purpose of the study was to clarify the role of SOD in wetland function and in the reclamation process. Dissolved oxygen loggers were inserted into dome-shaped chambers on the sediment to measure changes in oxygen demand. Complementary measurements of respiration (CO 2 elution) were used to quantify the biological sediment oxygen demand (BSOD) component of SOD. The chemical sediment oxygen demand (CSOD) was then determined by subtraction from SOD. Wetlands reclaimed using OSPM are expected to have a lower BSOD to CSOD ratio than reference wetlands. Residual ammonia in OSPM sediments may react with sulphate and bind phosphorus. This reduces phosphorus bioavailability and may impede submergent macrophyte growth. As such, wetlands affected by CSOD will have fewer submerged macrophytes than BSOD dominant wetlands.

Dynamic of the structure and biodiversity of macrozoobenthos in one ...

African Journals Online (AJOL)

xiongjing

2012-07-10

Jul 10, 2012 ... oxygen demand; BOD, biochemical oxygen demand. cause a diverse range of .... deterministic factors determining the elimination or replacement of species .... need for new approaches and concepts. Glob. Change Biol.

Untitled

African Journals Online (AJOL)

surface-water problem, affecting both which is the main tributary of the River running and still water demanding special. Gibe. Such waste discharge without any attention (2). form of treatment not only becomes a. The 5-day Biological Oxygen. Demand (BOD) is the best single strength potential health hazard to the nearby.

Preliminary Study on Treatment of Palm Oil Mill Effluent (POME by Sand Filtration-DBD Plasma System

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Ariadi Hazmi

2016-02-01

Full Text Available In the palm oil industry, open ponding, aerobic and anaerobic digestion, physicochemical treatment and membrane filtration are generally applied as conventional treatments of palm oil mill effluent (POME. In this study, a sand filtration-dielectric barrier discharge (DBD system was investigated as an alternative process for treating POME. This system can reduce land usage, processing time and costs compared to conventional systems. The removal efficiency of chemical oxygen demand (COD, biological oxygen demand (BOD5, and oil-grease in relation to the applied voltage were studied. Furthermore, the pH and temperature profiles were investigated. The obtained results indicate that the removal efficiency of COD, BOD5, and oil-grease increased with an increase of the applied voltage. The electrical energy consumption needed is about 10.56 kWh/L of POME.

201-IJBCS-Article-Dr S O Ayoola

African Journals Online (AJOL)

RHUMSIKI

Seasonal variation in fish distribution and physico-chemical parameters of wetland areas in Oyo ... The water pH, Biological Oxygen Demand (BOD) and Chemical Oxygen Demand ..... that low pH creates a stress situation in most organisms ...

Miniaturized and green method for determination of chemical oxygen demand using UV-induced oxidation with hydrogen peroxide and single drop microextraction

International Nuclear Information System (INIS)

Akhoundzadeh, Jeyran; Chamsaz, Mahmoud; Costas, Marta; Lavilla, Isela; Bendicho, Carlos

2013-01-01

We report on a green method for the determination of low levels of chemical oxygen demand. It is based on the combination of (a) UV-induced oxidation with hydrogen peroxide, (b) headspace single-drop microextraction with in-drop precipitation, and (c) micro-turbidimetry. The generation of CO 2 after photolytic oxidation followed by its sequestration onto a microdrop of barium hydroxide gives rise to a precipitate of barium carbonate which is quantified by turbidimetry. UV-light induced oxidation was studied in the absence and presence of H 2 O 2 , ultrasound, and ferrous ion. Determinations of chemical oxygen demand were performed using potassium hydrogen phthalate as a model compound. The optimized method gives a calibration curve that is linear between 3.4 and 20 mg L −1 oxygen. The detection limit was 1.2 mg L −1 of oxygen, and the repeatability (as relative standard deviation) was around 5 %. The method was successfully applied to the determination of chemical oxygen demand in different natural waters and a synthetic wastewater. (author)

Treatment of swine wastewater in continuous activated sludge systems under different dissolved oxygen conditions: Reactor operation and evaluation using modelling.

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Waki, Miyoko; Yasuda, Tomoko; Fukumoto, Yasuyuki; Béline, Fabrice; Magrí, Albert

2018-02-01

Swine wastewater was treated in two continuously aerated activated sludge (AS) systems at high (AS1: 1.7-2.6 mg/L) and low (AS2: 0.04-0.08 mg/L) dissolved oxygen (DO), and at three temperatures (10, 20, and 30 °C). Biochemical oxygen demand (BOD) removal was >94.8%. Meanwhile, total nitrogen (N) removal was significantly higher in AS2, at 64, 89, and 88%, than in AS1, at 12, 24, and 46%, for 10, 20, and 30 °C, respectively. The experimental data were considered in a simulation study using an AS model for BOD and N removal, which also included nitrite, free ammonia, free nitrous acid, and temperature. Simulations at high-DO showed that ammonium was partly oxidized into nitrate but not removed, whereas at low-DO ammonium was removed mainly through the nitrite shortcut in simultaneous nitrification-denitrification. This study demonstrates that treatment at low-DO is an effective method for removing N, and modelling a helpful tool for its optimization. Copyright © 2017 Elsevier Ltd. All rights reserved.

Analysis of tannery effluents from the Challawa industrial estate in ...

African Journals Online (AJOL)

Global Journal of Pure and Applied Sciences ... and some physicochemical parameters such as conductivity, solids, chloride, chromium, alkalinity, sulphide, chemical oxygen demand, COD, and biochemical oxygen demand, BOD, of the waste water were determined. ... Keywords: tannery, effluent, pollution, environment

Biodegradation of BOD and ammonia-free using bacterial consortium in aerated fixed film bioreactor (AF2B)

Science.gov (United States)

Prayitno, Rulianah, Sri; Saroso, Hadi; Meilany, Diah

2017-06-01

BOD and Ammonia-free (NH3-N) are pollutants of hospital wastewater which often exceed the quality standards. It is because biological processes in wastewater treatment plant (WWTP) have not been effective in degrading BOD and NH3-N. Therefore, a study on factors that influence the biodegradation of BOD and NH3-N by choosing the type of bacteria to improve the mechanisms of biodegradation processes is required. Bacterial consortium is a collection of several types of bacteria obtained from isolation process, which is known to be more effective than a single bacterial in degrading pollutants. On the other hand, AF2B is a type of reactor in wastewater treatment system. The AF2B contains a filter media that has a large surface area so that the biodegradation process of pollutants by microorganism can be improved. The objective of this research is to determine the effect of volume of starter and air supplies on decreasing BOD and NH3-N in hospital wastewater using bacterial consortium in the AF2B on batch process. The research was conducted in three stages: the making of the growth curve of the bacterial consortium, bacterial consortium acclimatization, and hospital wastewater treatment in the AF2B with batch process. The variables used are the volume of starter (65%, 75%, and 85% in volume) and air supplies (2.5, 5, and 7.5 L/min). Meanwhile, the materials used are hospital wastewater, bacterial consortium (Pseudomonas diminuta, Pseudomonas capica, Bacillius sp, and Nitrobacter sp), blower, and AF2B. AF2B is a plastic basin containing a filter media with a wasp-nest shape used as a medium for growing the bacterial consortium. In the process of making the growth curve, a solid form of bacterial consortium was dissolved in sterilized water, then grown in a nutrient broth (NB). Then, shaking and sampling were done at any time to determine the path growth of bacterial consortium. In the acclimatization process, bacterial isolates were grown using hospital wastewater as a

Treatment of high organic content wastewater from food-processing industry with the French vertical flow constructed wetland system.

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Paing, J; Serdobbel, V; Welschbillig, M; Calvez, M; Gagnon, V; Chazarenc, F

2015-01-01

This study aimed at determining the treatment performances of a full-scale vertical flow constructed wetlands designed to treat wastewater from a food-processing industry (cookie factory), and to study the influence of the organic loading rate. The full-scale treatment plant was designed with a first vertical stage of 630 m², a second vertical stage of 473 m² equipped with a recirculation system and followed by a final horizontal stage of 440 m². The plant was commissioned in 2011, and was operated at different loading rates during 16 months for the purpose of this study. Treatment performances were determined by 24 hour composite samples. The mean concentration of the raw effluent was 8,548 mg.L(-1) chemical oxygen demand (COD), 4,334 mg.L(-1) biochemical oxygen demand (BOD5), and 2,069 mg.L(-1) suspended solids (SS). Despite low nutrients content with a BOD5/N/P ratio of 100/1.8/0.5, lower than optimum for biological degradation (known as 100/5/1), mean removal performances were very high with 98% for COD, 99% for BOD5 and SS for the two vertical stages. The increasing of the organic load from 50 g.m(-2).d(-1) COD to 237 g.m(-2).d(-1) COD (on the first stage) did not affect removal performances. The mean quality of effluent reached French standards (COD < 125 mg.L(-1), BOD5 < 25 mg.L(-1), SS < 35 mg.L(-1)).

Treatment of amoxicillin by O3/Fenton process in a rotating packed bed.

Science.gov (United States)

Li, Mo; Zeng, Zequan; Li, Yingwen; Arowo, Moses; Chen, Jianfeng; Meng, Hong; Shao, Lei

2015-03-01

In this study, simulated amoxicillin wastewater was treated by the O3/Fenton process in a rotating packed bed (RPB) and the results were compared with the Fenton process and the O3 followed by Fenton (O3 + Fenton) process. The chemical oxygen demand (COD) removal rate and the ratio of 5-day biological oxygen demand to chemical oxygen demand (BOD5/COD) in the O3/Fenton process were approximately 17% and 26%, respectively, higher than those in the O3 + Fenton process with an initial pH of 3. The COD removal rate of the amoxicillin solution reached maximum at the Fe(II) concentration of 0.6 mM, temperature of 25 °C, rotation speed of 800 rpm and initial pH of 3. The BOD5/COD of the amoxicillin solution increased from 0 to 0.38 after the solution was treated by the O3/Fenton process. Analysis of the intermediates indicated that the pathway of amoxicillin degradation in the O3/Fenton process was similar to that in the O3 + Fenton process. Contrast experiment results showed that amoxicillin degradation was significantly intensified in the RPB. Copyright © 2014 Elsevier Ltd. All rights reserved.

Decoloration and degradation of Reactive Red-120 dye by electron beam irradiation in aqueous solution

International Nuclear Information System (INIS)

Paul, Jhimli; Rawat, K.P.; Sarma, K.S.S.; Sabharwal, S.

2011-01-01

The decoloration and degradation of aqueous solution of the reactive azo dye viz. Reactive Red-120 (RR-120) was carried out by electron beam irradiation. The change in decoloration percentage, removal of chemical oxygen demand (COD) and total organic carbon (TOC), solution pH and five-day biochemical oxygen demand (BOD 5 ) were investigated with respect to the applied dose. However, the concentration of the dye in the solution showed a great influence on all these observables. During the radiolysis process, it was found that the decoloration of dye was caused by the destruction of the chromophore group of the dye molecule, whereas COD and TOC removal were depended on the extent of mineralization of the dye. The decrease in pH during the radiolysis process indicated the fragmentation of the large dye molecule into smaller organic components mostly like smaller organic acids. The BOD 5 /COD ratio of the unirradiated dye solution was in the range of 0.1-0.2, which could be classified as non-biodegradable wastewater. However, the BOD 5 /COD ratio increased upon irradiation and it indicated the transformation of non-biodegradable dye solution into biodegradable solution. This study showed that electron beam irradiation could be a promising method for treatment of textile wastewater containing RR-120 dye.

Online total organic carbon (TOC) monitoring for water and wastewater treatment plants processes and operations optimization

Science.gov (United States)

Assmann, Céline; Scott, Amanda; Biller, Dondra

2017-08-01

Organic measurements, such as biological oxygen demand (BOD) and chemical oxygen demand (COD) were developed decades ago in order to measure organics in water. Today, these time-consuming measurements are still used as parameters to check the water treatment quality; however, the time required to generate a result, ranging from hours to days, does not allow COD or BOD to be useful process control parameters - see (1) Standard Method 5210 B; 5-day BOD Test, 1997, and (2) ASTM D1252; COD Test, 2012. Online organic carbon monitoring allows for effective process control because results are generated every few minutes. Though it does not replace BOD or COD measurements still required for compliance reporting, it allows for smart, data-driven and rapid decision-making to improve process control and optimization or meet compliances. Thanks to the smart interpretation of generated data and the capability to now take real-time actions, municipal drinking water and wastewater treatment facility operators can positively impact their OPEX (operational expenditure) efficiencies and their capabilities to meet regulatory requirements. This paper describes how three municipal wastewater and drinking water plants gained process insights, and determined optimization opportunities thanks to the implementation of online total organic carbon (TOC) monitoring.

Pengaruh Laju Alir Inlet Reaktor MSL terhadap Reduksi BOD, COD, TSS, dan Minyak/Lemak Limbah Cair Industri Minyak Goreng

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Salmariza Sy

2017-06-01

Full Text Available This research was conducted by treating edible oil industry wastewater used Multi Soil Layering (MSL method. The MSL reactor was built from a 200x120x200 cm concrete basin. Andisol soil was mixed with sawdust and fine charcoal at each ratio 5:1:1 based on dry weight as an impermeable layer. The flow rate variations were 250, 500, 1000, and 1500 L/m2.day. The observed pollutant parameters were BOD, COD, TSS, oil/fat, and pH. The results showed that MSL reactor was effective to decrease the pollutant content of edible oil industry wastewater. The reactor could reduce concentration of effluent parameters below standard except for oil/fat parameters at high flow rates. In the effluent was found BOD 0.66-14.22 mg/L, COD 5-69 mg/L, TSS 9-26 mg/L, and oil/fat 2-9 mg/L. The flow rate had an effect on reduction efficiency of BOD, COD, TSS, and oil/fat but did not effect pH as all flow rate could raise pH 6.37-6.95 became pH 6.99-7.24. The lower the flow rate the higher the reduction efficiency. The reduction efficiency at flow rates 250 and 1500 L/m2 days for BOD were 99% and 86%, COD were 96% and 71%, TSS were 88% and 77%, and oil/fat were 80% and 60%.ABSTRAK  Penelitian ini dilakukan dengan mengolah air limbah industri minyak goreng menggunakan metoda Multi Soil Layering (MSL. Reaktor MSL dibuat dari beton berbentuk bak ukuran 200x120x200 cm. Tanah andisol dicampur dengan serbuk gergaji dan arang halus pada rasio masing-masing 5:1:1 berdasarkan berat kering sebagai penyusun lapisan impermeable. Variasi laju alir yaitu 250, 500, 1000, dan 1500 L/m2.hari. Parameter pencemar yang dianalisis meliputi BOD, COD, TSS, minyak/lemak, dan pH. Hasil penelitian menunjukkan bahwa reaktor MSL sangat efektif untuk menurunkan kandungan zat pencemar limbah cair industri minyak goreng. Reaktor dapat mereduksi konsentrasi parameter outlet sampai dibawah baku mutu yang distandarkan kecuali untuk parameter miyak/lemak pada perlakuan laju alir tinggi. Pada effluen

Non-biodegradable landfill leachate treatment by combined process of agitation, coagulation, SBR and filtration.

Science.gov (United States)

Abood, Alkhafaji R; Bao, Jianguo; Du, Jiangkun; Zheng, Dan; Luo, Ye

2014-02-01

This study describes the complete treatment of non-biodegradable landfill leachate by combined treatment processes. The processes consist of agitation as a novel stripping method used to overcome the ammonia toxicity regarding aerobic microorganisms. The NH3-N removal ratio was 93.9% obtained at pH 11.5 and a gradient velocity (G) 150 s(-1) within a five-hour agitation time. By poly ferric sulphate (PFS) coagulation followed the agitation process; chemical oxygen demand (COD) and biological oxygen demand (BOD5) were removed at 70.6% and 49.4%, respectively at an optimum dose of 1200 mg L(-1) at pH 5.0. The biodegradable ratio BOD5/COD was improved from 0.18 to 0.31 during pretreatment step by agitation and PFS coagulation. Thereafter, the effluent was diluted with sewage at a different ratio before it was subjected to sequencing batch reactor (SBR) treatment. Up to 93.3% BOD5, 95.5% COD and 98.1% NH3-N removal were achieved by SBR operated under anoxic-aerobic-anoxic conditions. The filtration process was carried out using sand and carbon as a dual filter media as polishing process. The final effluent concentration of COD, BOD5, suspended solid (SS), NH3-N and total organic carbon (TOC) were 72.4 mg L(-1), 22.8 mg L(-1), 24.2 mg L(-1), 18.4 mg L(-1) and 50.8 mg L(-1) respectively, which met the discharge standard. The results indicated that a combined process of agitation-coagulation-SBR and filtration effectively eliminated pollutant loading from landfill leachate. Copyright © 2013 Elsevier Ltd. All rights reserved.

Physicochemical Characteristics of River Water Downstream of a Large Tropical Hydroelectric Dam

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Teck-Yee Ling

2016-01-01

Full Text Available Water quality in the downstream river of a hydroelectric dam may be affected by the structural design and operation. To date, little is known about the water quality downstream of the largest dam in Malaysia, the Bakun hydroelectric dam. Therefore, the objective of the study was to determine the water quality downstream of the dam when the spillway was closed and when it was opened. Results of the study indicate that the dam plays a significant role in regulating the water quality downstream of it. When the spillway was closed, pH and oxygen were lower in the river where DO was below 5 mg/L. When the spillway was opened, the water quality improved in terms of oxygen content (>8.0 mg/L, total sulphide (TS, and chemical oxygen demand (COD but deteriorated in terms of five-day biochemical oxygen demand (BOD5, total ammonia nitrogen (TAN, and total phosphorus (TP. Additionally, the intensity of the impacts, particularly BOD5, COD, and TAN, shows a declining trend as distance from the dam increases. This study shows that impacts on the water quality extend to a distance of 32 km from the dam particularly turbidity and DO and opening the spillway changes the water quality significantly.

ANALISIS KUALITAS AIR SUMUR GALI DI KAWASAN PARIWISATA SANUR

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I.A.M. Trisnawulan

2012-11-01

Full Text Available parts of sampling areas: Sanur Kaja 5-6 meter (SA2 and 7-8 meter (SA3, Kelurahan Sanur 3-4 meter(SB1 and 5-6 meter (SB2, Sanur Kauh 3-4 meter (SC1 and 5-6 meter (SC2, using Cluster RandomSampling method.The result in April showed that from 14 parameters examined only 5 parameters have highconcentration than the acceptable drinking water standard (PPRI no.82, 2001. Those parameters areDissolved Oxygen (DO, Biochemical Oxygen Demand (BOD5, Nitrate (NO3, Phosphate (PO4, and TotalColi form. While the result of the analyses in June showed that 9 from 14 parameters have highconcentration than the acceptable drinking water standard ( PPRI no 82, 2001 they are Total DissolvedSolid (TDS, Dissolved Oxygen (DO, Biochemical Oxygen Demand (BOD5, Nitrate (NO3, Nitrite (NO2,Ammonia (NH3, Phosphate (PO4, E. coli and Total Coli form.The increasing concentrations indicate some pollution has occurred in these sampling areas. Theobservation has shown that most of the people in Sanur dump their waste water into the ground, which easilyabsorb through the porous soil then contaminate the ground water aquifer. Based on the water quality status using the pollution index, almost all the sampling areas have low pollution index, except the one at SanurKaja 7-8 m (SA3 has moderate pollution index.

BAYESIAN PARAMETER ESTIMATION IN A MIXED-ORDER MODEL OF BOD DECAY. (U915590)

Science.gov (United States)

We describe a generalized version of the BOD decay model in which the reaction is allowed to assume an order other than one. This is accomplished by making the exponent on BOD concentration a free parameter to be determined by the data. This "mixed-order" model may be ...

Data on wastewater treatment plant by using wetland method, Babol, Iran

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Yousef Dadban Shahamat

2018-02-01

Full Text Available Date in this paper highlights the applications of constructed horizontal surface flow (HF-CW wetland with two different local plants (Louis latifoila and Phragmites -australis (Cav. Trin at the wastewater treatment plant in Babol city. This system was designed as an advanced treatment unit in field scale after the treatment plant. Parameters such as Total Dissolved Solid (TDS, Total Suspended Solid (TSS, Turbidity, Biological Oxygen Demand (BOD and Chemical Oxygen Demand (COD, were investigated. The result shows that treatment efficiency increases with the passage of time. The efficiency of Phragmites planted setups in open environment was fairly good for all studied parameters (28.6% of TDS, 94.4% for TSS, 79.8% for turbidity, 93.7% for BOD and 82.6% for COD. The efficiency of the latifoila set up was also good, but lower than that of Phragmites (26.5% of TDS, 76.9% for TSS, 71.5% for turbidity, 79.1 for BOD and 68.8% for COD. In brief, the obtained dates show that using local plants in (HF-CW wetland not only effectively reduces various contaminants from the effluent of the wastewater according to Effluent Guideline regulations (WHO & EPA, but it is also a cost- effective and environmentally friendly method. Also, it was calculated that in full scale operation [time (1 day and a depth (0.3 m], 8 ha of wetland was needed. Keywords: BOD, Babol, COD, Horizontal subsurface flow wetland, TSS, TSD

Influence of Hudiara Drain Water Irrigation on Trace Elements Load ...

African Journals Online (AJOL)

... Drain Water Irrigation on Trace Elements Load In Soil And Uptake By Vegetables. ... This polluted water not only contains organic matter and crop nutrients but also ... Plant samples were collected at maturity from all the monitoring points. ... (DO), Chemical Oxygen Demand (COD) and Biological Oxygen Demand (BOD) ...

Enhancement of biodegradability of real textile and dyeing wastewater by electron beam irradiation

International Nuclear Information System (INIS)

He, Shijun; Sun, Weihua; Wang, Jianlong; Chen, Lvjun; Zhang, Youxue; Yu, Jiang

2016-01-01

A textile and dyeing wastewater treatment plant is going to be upgraded due to the stringent discharge standards in Jiangsu province, China, and electron beam irradiation is considering to be used. In order to determine the suitable location of the electron accelerator in the process of wastewater treatment plant, the effects of electron beam (EB) irradiation on the biodegradability of various real wastewater samples collecting from the different stages of the wastewater treatment plant, the values of chemical oxygen demand (COD), biochemical oxygen demand (BOD 5 ), and the ratio of BOD 5 and COD (BOD 5 /COD), were compared before and after EB irradiation. During EB irradiation process, color indices and absorbance at 254 nm wavelength (UV 254 ) of wastewater were also determined. The results showed that EB irradiation pre-treatment cannot improve the biodegradability of raw textile and dyeing wastewater, which contains a large amount of biodegradable organic matters. In contrast, as to the final effluent of biological treatment process, EB irradiation can enhance the biodegradability to 224%. Therefore, the promising way is to apply EB irradiation as a post-treatment of the conventional biological process. - Highlights: • Irradiation pre-treatment did not improve the raw textile wastewater biodegradability. • Irradiation can highly enhance the biodegradability of biological treated effluent. • EB irradiation can be used as a post-treatment after biological process.

Spatial-temporal variation of surface water quality in the downstream region of the Jakara River, north-western Nigeria: A statistical approach.

Science.gov (United States)

Mustapha, Adamu; Aris, Ahmad Zaharin; Ramli, Mohammad Firuz; Juahir, Hafizan

2012-01-01

The pollution status of the downstream section of the Jakara River was investigated. Dissolved oxygen (DO), 5-day biochemical oxygen demand (BOD(5)), chemical oxygen demand (COD), suspended solids (SS), pH, conductivity, salinity, temperature, nitrogen in the form of ammonia (NH(3)), turbidity, dissolved solids (DS), total solids (TS), nitrates (NO(3)), chloride (Cl) and phosphates (PO(3-)(4)) were evaluated, using both dry and wet season samples, as a measure of variation in surface water quality in the area. The results obtained from the analyses were correlated using Pearson's correlation matrix, principal component analysis (PCA) and paired sample t-tests. Positive correlations were observed for BOD(5), NH(3), COD, and SS, turbidity, conductivity, salinity, DS, TS for dry and wet seasons, respectively. PCA was used to investigate the origin of each water quality parameter, and yielded 5 varimax factors for each of dry and wet seasons, with 70.7 % and 83.1 % total variance, respectively. A paired sample t-test confirmed that the surface water quality varies significantly between dry and wet season samples (P < 0.01). The source of pollution in the area was concluded to be of anthropogenic origin in the dry season and natural origins in the wet season.

Anaerobic/aerobic treatment of greywater via UASB and MBR for unrestricted reuse.

Science.gov (United States)

Abdel-Shafy, Hussein I; Al-Sulaiman, Ahmed Makki; Mansour, Mona S M

2015-01-01

The aim of the present study was to investigate the efficiency of integrated up-flow anaerobic sludge blanket (UASB) as anaerobic system followed by membrane bioreactor (MBR) as aerobic system for the treatment of greywater for unrestricted reuse. Pilot-scale UASB and MBR units were installed and operated in the NRC, Egypt. Real raw greywater was subjected to UASB and the effluent was further treated with microfiltration MBR. The necessary trans-membrane pressure difference is applied by the water head above the membrane (gravity flow) without any energy input. The average characteristics of the raw greywater were 95, 392, 298, 10.45, 0.4, 118.5 and 28 mg/L for total suspended solids (TSS), chemical oxygen demand (COD), biochemical oxygen demand (BOD), total phosphates, nitrates, oil and grease, and total Kjeldahl nitrogen (TKN), respectively. The pH was 6.71. The UASB treatment efficiency reached 19.3, 57.8, 67.5 and 83.7% for TSS, COD, BOD5 and oil and grease, respectively. When the UASB effluent was further treated with MBR, the overall removal rate achieved 97.7, 97.8, 97.4 and 95.8% for the same parameters successively. The characteristics of the final effluent reached 2.5, 8.5, 6.1, 0.95, 4.6 and 2.3 mg/L for TSS, COD, BOD, phosphates, oil and grease and TKN, respectively. This final treated effluent could cope with the unrestricted water reuse of local Egyptian guidelines.

Sampling and sample handling procedures for priority pollutants in surface coal mining wastewaters. [Detailed list to be analyzed for

Energy Technology Data Exchange (ETDEWEB)

Hayden, R. S.; Johnson, D. O.; Henricks, J. D.

1979-03-01

The report describes the procedures used by Argonne National Laboratory to sample surface coal mine effluents in order to obtain field and laboratory data on 110 organic compounds or classes of compounds and 14 metals and minerals that are known as priority pollutants, plus 5-day biochemical oxygen demand (BOD/sub 5/), total organic carbon (TOC), chemical oxygen demand (COD), total dissolved solids (TDS), and total suspended solids (TSS). Included are directions for preparation of sampling containers and equipment, methods of sampling and sample preservation, and field and laboratory protocols, including chain-of-custody procedures. Actual analytical procedures are not described, but their sources are referenced.

Sequencing treatment of industrial wastewater with ultraviolet/H2O2 advanced oxidation and moving bed bioreactor

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Mohammad Mehdi Mehrabani Ardekani

2015-01-01

Full Text Available Aims: The main purpose of this study was to determine the efficiency of a sequencing treatment including ultraviolet (UV/H 2 O 2 oxidation followed by a moving bed bioreactor (MBBR. Materials and Methods: Effect of solution pH, reaction time, and H 2 O 2 concentration were investigated for an industrial wastewater sample. The effluent of the advanced oxidation processes unit was introduced to the MBBR operated for three hydraulic retention times of 4, 8, and 12 h. Results: The optimum condition for industrial wastewater treatment via advanced oxidation was solution pH: 7, H 2 O 2 dose: 1000 mg/L and 90 min reaction time. These conditions led to 74.68% chemical oxygen demand (COD removal and 66.15% biochemical oxygen demand (BOD 5 removal from presedimentation step effluent that initially had COD and BOD 5 contents of 4,400 and 1,950 mg/L, respectively. Conclusion: Combination of UV/H 2 O 2 advanced oxidation with MBBR could result in effluents that meet water quality standards for discharge to receiving waters.

Biological treatment of textile mill wastewater in the. presence of activated carbon

International Nuclear Information System (INIS)

Liaquat, F.; Hassan, M.; Mahboob, S.; Rehman, A.; Liaquat, S.; Khalid, Z.M.

2005-01-01

The main goal of this study was to find out effectiveness of biological treatment for the reduction in chemical oxygen demand (COD) and biological oxygen demand (BOD) of the textile processing industrial wastewater in the absence and presence of granular activated carbon (GAC) in shake flask experiment. To check the pollution level, physio-chemical analysis of effluent from Amtex industry (Faisalabad) was carried out. The outlet effluent contained high value of COD (1100 mg/l), BOD (309 mg/l) with pH 9.2, electrical conductivity (Ec) 3.7 mS/m, total dissolved solids (TDS) (2640 mg/l), total solids (TS) (3060 mg/l), total suspended solids (TSS) (420 19/l) and phenol (.34 mg/l). After initial period of activated sludge adaptation to wastewater, shake flask batch cultures (with and without activated carbon) were operated on lab scale. The COD and BOD were noted after very 12 hours for 3 days. The maximum reduction in COD (82%) and BOD (90%) was observed biological treatment in presence of activated carbon at retention time of 72 hours. (author)

Advanced landfill leachate treatment using iron-carbon microelectrolysis- Fenton process: Process optimization and column experiments.

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Wang, Liqun; Yang, Qi; Wang, Dongbo; Li, Xiaoming; Zeng, Guangming; Li, Zhijun; Deng, Yongchao; Liu, Jun; Yi, Kaixin

2016-11-15

A novel hydrogen peroxide-enhanced iron-carbon (Fe-C) microelectrolysis reactor was proposed for the pretreatment of mature landfill leachate. This reactor, combining microelectrolysis with Fenton process, revealed high treatment efficiency. The operating variables, including Fe-C dosage, H2O2 concentration and initial pH, were optimized by the response surface methodology (RSM), regarding the chemical oxygen demand (COD) removal efficiency and biochemical oxygen demand: chemical oxygen demand (BOD5/COD) as the responses. The highest COD removal (74.59%) and BOD5/COD (0.50) was obtained at optimal conditions of Fe-C dosage 55.72g/L, H2O2 concentration 12.32mL/L and initial pH 3.12. Three-dimensional excitation and emission matrix (3D-EEM) fluorescence spectroscopy and molecular weight (MW) distribution demonstrated that high molecular weight fractions such as refractory fulvic-like substances in leachate were effectively destroyed during the combined processes, which should be attributed to the combination oxidative effect of microelectrolysis and Fenton. The fixed-bed column experiments were performed and the breakthrough curves at different flow rates were evaluated to determine the practical applicability of the combined process. All these results show that the hydrogen peroxide-enhanced iron-carbon (Fe-C) microelectrolysis reactor is a promising and efficient technology for the treatment of mature landfill leachate. Copyright © 2016 Elsevier B.V. All rights reserved.

Sediment oxygen demand in the lower Willamette River, Oregon, 1994

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Caldwell, James M.; Doyle, Micelis C.

1995-01-01

An investigation of sediment oxygen demand (SOD) at the interface of the stream and stream bed was performed in the lower Willamette River (river mile 51 to river mile 3) during August, 1994, as part of a cooperative project with the Oregon Department of Environmental Quality. The primary goals of the investigation were to measure the spatial variability of SOD in the lower Willamette River and to relate SOD to bottom-sediment characteristics.

Removal of Heavy Metals from Steel Making Waste Water by Using Electric Arc Furnace Slag

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C. L. Beh

2012-01-01

Full Text Available This work investigated the reduction of chemical oxygen demand (COD, biological oxygen demand (BOD, total suspended solids (TSS and the concentration of heavy metals of wastewater from a steel making plant. Adsorption experiments were carried out by electric arc furnace slag (EAFS in a fixed-bed column mode. The raw wastewater did not meet the standard B limitations, having high values of BOD, COD, TSS, Iron, Zinc, Manganese and Copper. After passing through the fixed bed column, BOD, COD and TSS values decreased to 1.6, 6.3 and <2 mgL-1, respectively while the concentration of Iron, Zinc, Manganese and Copper were 0.08, 0.01, 0.03 and 0.07 mgL-1, respectively. The results confirmed that EAFS can be used as an efficient adsorbent for producing treated water that comply with the Standard B limitations for an industrial effluent.

Degradation and biodegradability improvement of the olive mill wastewater by peroxi-electrocoagulation/electrooxidation-electroflotation process with bipolar aluminum electrodes.

Science.gov (United States)

Esfandyari, Yahya; Mahdavi, Yousef; Seyedsalehi, Mahdi; Hoseini, Mohammad; Safari, Gholam Hossein; Ghozikali, Mohammad Ghanbari; Kamani, Hossein; Jaafari, Jalil

2015-04-01

Olive mill wastewater is considered as one of the most polluting effluents of the food industry and constitutes a source of important environmental problems. In this study, the removal of pollutants (chemical oxygen demand (COD), biochemical oxygen demand (BOD5), polyphenols, turbidity, color, total suspended solids (TSS), and oil and grease) from olive oil mill processing wastewater by peroxi-electrocoagulation/electrooxidation-electroflotation process with bipolar aluminum electrodes was evaluated using a pilot continuous reactor. In the electrochemical unit, aluminum (Al), stainless steel, and RuO2/Ti plates were used. The effects of pH, hydrogen peroxide doses, current density, NaCl concentrations, and reaction times were studied. Under optimal conditions of pH 4, current density of 40 mA/m(2), 1000 mg/L H2O2, 1 g/L NaCl, and 30-min reaction time, the peroxi-electrochemical method yielded very effective removal of organic pollution from the olive mill wastewater diluted four times. The treatment process reduced COD by 96%, BOD5 by 93.6%, total, polyphenols by 94.4%, color by 91.4%, turbidity by 88.7, suspended solids by 97% and oil and grease by 97.1%. The biodegradability index (BOD5/COD) increased from 0.29 to 0.46. Therefore, the peroxi-electrocoagulation/electrooxidation-electroflotation process is considered as an effective and feasible process for pre-treating olive mill wastewater, making possible a post-treatment of the effluent in a biological system.

Characterization of chromophoric dissolved organic matter and relationships among PARAFAC components and water quality parameters in Heilongjiang, China.

Science.gov (United States)

Cui, Hongyang; Shi, Jianhong; Qiu, Linlin; Zhao, Yue; Wei, Zimin; Wang, Xinglei; Jia, Liming; Li, Jiming

2016-05-01

Chromophoric dissolved organic matter (CDOM) is an important optically active substance that can transports nutrients and pollutants from terrestrial to aquatic systems. Additionally, it is used as a measure of water quality. To investigate the source and composition of CDOM, we used chemical and fluorescent analyses to characterize CDOM in Heilongjiang. The composition of CDOM can be investigated by excitation-emission matrix (EEM) fluorescence and parallel factor analysis (PARAFAC). PARAFAC identified four individual components that were attributed to microbial humic-like (C1) and terrestrial humic-like (C2-4) in water samples collected from the Heilongjiang River. The relationships between the maximum fluorescence intensities of the four PARAFAC components and the water quality parameters indicate that the dynamic of the four components is related to nutrients in the Heilongjiang River. The relationships between the fluorescence component C3 and the biochemical oxygen demand (BOD5) indicates that component C3 makes a great contribution to BOD5 and it can be used as a carbon source for microbes in the Heilongjiang River. Furthermore, the relationships between component C3, the particulate organic carbon (POC), and the chemical oxygen demand (CODMn) show that component C3 and POC make great contributions to BOD5 and CODMn. The use of these indexes along with PARAFAC results would be of help to characterize the co-variation between the CDOM and water quality parameters in the Heilongjiang River.

Performance of hybrid subsurface constructed wetland system for piggery wastewater treatment.

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Zhang, X; Inoue, T; Kato, K; Harada, J; Izumoto, H; Wu, D; Sakuragi, H; Ietsugu, H; Sugawara, Y

2016-01-01

The objective of this study was to evaluate performance of a hybrid constructed wetland (CW) built for high organic content piggery wastewater treatment in a cold region. The system consists of four vertical and one horizontal flow subsurface CWs. The wetland was built in 2009 and water quality was monitored from the outset. Average purification efficiency of this system was 95±5, 91±7, 89±8, 70±10, 84±15, 90±6, 99±2, and 93±16% for biochemical oxygen demand (BOD5), chemical oxygen demand (COD), total carbon (TC), total nitrogen (TN), ammonium-N (NH4-N), total phosphorus (TP), total coliform (T. Coliform), and suspended solids (SS), respectively during August 2010-December 2013. Pollutant removal rate was 15±18 g m(-2) d(-1), 49±52 g m(-2) d(-1), 6±4 g m(-2) d(-1), 7±5 g m(-2) d(-1), and 1±1 g m(-2) d(-1) for BOD5, COD, TN, NH4-N, and TP, respectively. The removal efficiency of BOD5, COD, NH4-N, and SS improved yearly since the start of operation. With respect to removal of TN and TP, efficiency improved in the first three years but slightly declined in the fourth year. The system performed well during both warm and cold periods, but was more efficient in the warm period. The nitrate increase may be attributed to a low C/N ratio, due to limited availability of carbon required for denitrification.

Reliability of BOD POD Measurements Remains High After a Short-Duration Low-Carbohydrate Diet.

Science.gov (United States)

Greer, Beau Kjerulf; Edsall, Kathleen M; Greer, Anna E

2016-04-01

The purpose of the current study was to determine whether expected changes in body weight via a 3-day low-carbohydrate (LC) diet will disrupt the reliability of air displacement plethysmography measurements via BOD POD. Twenty-four subjects recorded their typical diets for 3 days before BOD POD and 7-site skinfold analyses. Subjects were matched for lean body mass and divided into low-CHO (LC) and control (CON) groups. The LC group was given instruction intended to prevent more than 50 grams/day of carbohydrate consumption for 3 consecutive days, and the CON group replicated their previously recorded diet. Body composition measurements were repeated after dietary intervention. Test-retest reliability measures were significant (p fat percentage in both the LC and the CON groups (rs = .993 and .965, respectively). Likewise, skinfold analysis for body fat percentage reliability was high in both groups (rs = .996 and .997, respectively). There were significant differences between 1st and 2nd BOD POD measurements for body mass (72.9 ± 13.3 vs. 72.1 ± 13.0 kg [M ± SD]) and body volume (69.0 ± 12.7-68.1 ± 12.2 L) in the LC group (p .05) in BOD POD-determined body fat percentage, lean body mass, or fat mass between the 1st and 2nd trial in either group. Body composition measures via BOD POD and 7-site skinfolds remain reliable after 3 days of an LC diet despite significant decreases in body mass.

PEMANFAATAN SPUIT BEKAS SEBAGAI MEDIA BIOFILTRASI DALAM MENURUNKAN KADAR BOD DAN COD AIR LIMBAH LAUNDRY

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Susilawati Susilawati

2016-07-01

Full Text Available Abstract: Utilization Spuit Used As Media biofilters on Reducing levels of BOD and COD Wastewater Laundry. The aim of this study was to test the ability of the media syringe biofiltration method used in lowering levels of BOD and COD in waste water laundry Hospital Dr. Soedarso Pontianak. This research is a quasi-experimental research design with one group pretest-posttest. Laboratory results mean BOD levels before processing is 103.63 mg/L and the average after processing into 46.41 mg/ L, with a value of 55.21 % effectiveness. While the average COD level before processing is 413.70 mg / L and the average after processing into a 195.88 mg/L with a value of 45.92% effectiveness. Expected to other researchers to control the pH and blowers before treatment and during treatment, as it will affect the final result. Abstrak : Pemanfaatan Spuit Bekas Sebagai Media Biofiltrasi Dalam Menurunkan Kadar BOD dan COD Air Limbah Laundry. Tujuan dari penelitian ini untuk menguji kemampuan metode biofiltrasi dengan media spuit bekas pakai dalam menurunkan kadar BOD dan COD pada air limbah laundry RSUD Dr. Soedarso Pontianak. Penelitian ini merupakan penelitian eksperimen semu dengan rancangan penelitian one group pre test post test. Hasil laboratorium rata-rata kadar BOD sebelum pengolahan yaitu 103.63 mg/L dan rata-rata setelah pengolahan menjadi 46.41 mg/L, dengan nilai efektivitas 55,21 %. Sedangkan rata-rata kadar COD sebelum pengolahan yaitu 413.70 mg/L dan rata-rata setelah pengolahan menjadi 195.88 mg/L dengan nilai efektivitas 45,92 %. Diharapkan kepada peneliti lain untuk mengontrol pH dan blower sebelum perlakuan dan pada saat perlakuan, jika melakukan penelitian sejenis karena akan mempengaruhi hasil akhir.

Modeling of wastewater quality in an urban area during festival and rainy days.

Science.gov (United States)

Obaid, H A; Shahid, S; Basim, K N; Chelliapan, S

2015-01-01

Water pollution during festival periods is a major problem in all festival cities across the world. Reliable prediction of water pollution is essential in festival cities for sewer and wastewater management in order to ensure public health and a clean environment. This article aims to model the biological oxygen demand (BOD(5)), and total suspended solids (TSS) parameters in wastewater in the sewer networks of Karbala city center during festival and rainy days using structural equation modeling and multiple linear regression analysis methods. For this purpose, 34 years (1980-2014) of rainfall, temperature and sewer flow data during festival periods in the study area were collected, processed, and employed. The results show that the TSS concentration increases by 26-46 mg/l while BOD(5) concentration rises by 9-19 mg/l for an increase of rainfall by 1 mm during festival periods. It was also found that BOD(5) concentration rises by 4-17 mg/l for each increase of 10,000 population.

Petrographic study of the Korean anthracite for utilization (VII)

Energy Technology Data Exchange (ETDEWEB)

Park, Hong Soo; Lee, Choon Oh; Park, Suk Whan [Korea Institute of Geology Mining and Materials, Taejon (Korea, Republic of)

1997-12-01

This research was initiated for the development of filtering materials those can be used in waste water treatment sites. The selected Jangseong coal for filtering material has low Hardgrove Grindability Index(HGI:38.38). For feasibility study, the small scale of filtration tester was built on the waste water treatment plant of Samdu dye Co. to use the precipitated water during filtration test processed by purifying system. Measurement items are filtration rate, temperature of waste water, Electric Conductivity(EC), pH, Turbidity, Dissolved Oxygen(DO), Chemical Oxygen Demand (COD), Bio-chemical Oxygen Demand(BOD), Salinity, Total Dissolved solids(TDS) and trace elements content(Zn, Si, Fe, Mg, K, Cu, Sr, Mn, Ca, Na, SO{sub 4}, Ni, Pb, Cd) of the supplied water and filtered water were carried out to find the filtration capacity of coal. The results indicated decreasing degree in turbidity (15.1%), COD(22.1%), BOD(56.8%), color(7.4%) and increasing degree in DO(10.5%). Trace elements removal degree of filtered waste water were about 17.1% for Fe and 10.7% for Zn. (author). 40 refs., 22 tabs., 26 figs.

Mineral dust emission from the Bodélé Depression, northern Chad, during BoDEx 2005

Science.gov (United States)

Todd, Martin C.; Washington, Richard; Martins, José Vanderlei; Dubovik, Oleg; Lizcano, Gil; M'bainayel, Samuel; Engelstaedter, Sebastian

2007-03-01

Mineral dust in the atmosphere is an important component of the climate system but is poorly quantified. The Bodélé Depression of northern Chad stands out as the world's greatest source region of mineral dust into the atmosphere. Frequent dust plumes are a distinguishing feature of the region's climate. There is a need for more detailed information on processes of dust emission/transport and dust optical properties to inform model simulations of this source. During the Bodélé Dust Experiment (BoDEx) in 2005, instrumentation was deployed to measure dust properties and boundary layer meteorology. Observations indicate that dust emission events are triggered when near-surface wind speeds exceed 10 ms-1, associated with synoptic-scale variability in the large-scale atmospheric circulation. Dust emission pulses in phase with the diurnal cycle of near-surface winds. Analysis of dust samples shows that the dust consists predominantly of fragments of diatomite sediment. The particle size distribution of this diatomite dust estimated from sun photometer data, using a modified Aeronet retrieval algorithm, indicates a dominant coarse mode (radius centered on 1-2 μm) similar to other Saharan dust observations. Single-scattering albedo values are high, broadly in line with other Saharan dust even though the diatomite composition of dust from the Bodélé is likely to be unusual. The radiative impact of high dust loadings results in a reduction in surface daytime maximum temperature of around 7°C in the Bodélé region. Using optical and physical properties of dust obtained in the field, we estimate the total dust flux emitted from the Bodélé to be 1.18 ± 0.45 Tg per day during a substantial dust event. We speculate that the Bodélé Depression (˜10,800 km2) may be responsible for between 6-18% of global dust emissions, although the uncertainty in both the Bodélé and global estimates remains high.

Evaluation of effluents from bench-scale treatment combinations for landfill leachate in Ibadan, Nigeria.

Science.gov (United States)

Aluko, Olufemi Oludare; Sridhar, Mkc

2014-01-01

The removal of pollutants in landfill leachate was investigated using constructed wetlands, a trickling filter, alum flocculation and coagulation, and a sequencing batch reactor in various combinations. Thirteen combined operations were investigated involving three out of the four unit treatment methods in series. The study was conducted because unit operations, though achieved reductions in pollutants concentrations had effluent values above the national regulatory guideline values. The suspended solids of effluents were permissible in most treatment processes, while reductions in 5-day biochemical oxygen demand (BOD5), chemical oxygen demand (COD) and ammonia (NH3) of leachates ranged from 80% to 97%; 86% to 97% and 92% to 98% respectively. However, there were significant increases in nitrate (85%) and dissolved oxygen of treatment (218%). In addition, the characteristics of the recommended treatment sequence, involving constructed wetlands, alum and trickling filter produced effluents with reductions in colour (97%), alkalinity (97%), BOD (97%), COD (97%) and NH3 (98%), and in metals, except nickel (29% reduction from the influent values). The recommended treatment combination is suitable for effective leachate management at the landfill. The cost of constructing and operating the recommended treatment combination at the facility, for 5 years, would be NGN6,009,750.00 ($38,036.39). The performance should be monitored on site prior to full adoption if effluent characteristics remain consistently low over dry and wet seasons.

Performance of A Pilot-Scale Vermifilter for the Treatment of A Real Hospital Wastewater

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Nahid Ghobadi

2016-12-01

Full Text Available In this study, the performance of a pilot-scale vermifilter (VF for the treatment of hospital wastewater using the earthworm species Eisenia fetida was evaluated. The earthworms’ gut acts as a bioreactor and can ingest the wastewater solid and liquid organic wastes and expel these as vermicompost. A pilot-scale vermifilter was installed and operated for 133 days in one of hospitals in Hamadan city; the designed system was fed with the influent passed through coarse and fine grillage and the sedimentation tank of the hospital’s sanitary collection system. In order to study the efficiency of the system, the variations of pH value, chemical oxygen demand (COD, biochemical oxygen demand (BOD5, and total suspended solids (TSS were measured. In addition, a conventional geofilter (GF without Earthworm was used as the experimental control. The vermifiltration caused a significant decrease in the levels of COD (75%, BOD5 (93%, and TSS (89% as well as neutralized pH in the wastewater. Also, these contents in the geofilter were observed to be 65%, 71%, and 71%, respectively. The vermifiltration technology can, therefore, be applied as an environmentally friendly method for hospital wastewater treatment.

Nitrogen fixation in the activated sludge treatment of thermomechanical pulping wastewater: effect of dissolved oxygen.

Science.gov (United States)

Slade, A H; Anderson, S M; Evans, B G

2003-01-01

N-ViroTech, a novel technology which selects for nitrogen-fixing bacteria as the bacteria primarily responsible for carbon removal, has been developed to treat nutrient limited wastewaters to a high quality without the addition of nitrogen, and only minimal addition of phosphorus. Selection of the operating dissolved oxygen level to maximise nitrogen fixation forms a key component of the technology. Pilot scale activated sludge treatment of a thermomechanical pulping wastewater was carried out in nitrogen-fixing mode over a 15 month period. The effect of dissolved oxygen was studied at three levels: 14% (Phase 1), 5% (Phase 2) and 30% (Phase 3). The plant was operated at an organic loading of 0.7-1.1 kg BOD5/m3/d, a solids retention time of approximately 10 d, a hydraulic retention time of 1.4 d and a F:M ratio of 0.17-0.23 mg BOD5/mg VSS/d. Treatment performance was very stable over the three dissolved oxygen operating levels. The plant achieved 94-96% BOD removal, 82-87% total COD removal, 79-87% soluble COD removal, and >99% total extractives removal. The lowest organic carbon removals were observed during operation at 30% DO but were more likely to be due to phosphorus limitation than operation at high dissolved oxygen, as there was a significant decrease in phosphorus entering the plant during Phase 3. Discharge of dissolved nitrogen, ammonium and oxidised nitrogen were consistently low (1.1-1.6 mg/L DKN, 0.1-0.2 mg/L NH4+-N and 0.0 mg/L oxidised nitrogen). Discharge of dissolved phosphorus was 2.8 mg/L, 0.1 mg/L and 0.6 mg/L DRP in Phases 1, 2 and 3 respectively. It was postulated that a population of polyphosphate accumulating bacteria developed during Phase 1. Operation at low dissolved oxygen during Phase 2 appeared to promote biological phosphorus uptake which may have been affected by raising the dissolved oxygen to 30% in Phase 3. Total nitrogen and phosphorus discharge was dependent on efficient secondary clarification, and improved over the course of

Application of Microbial BOD Sensors in Marine Monitoring

Institute of Scientific and Technical Information of China (English)

张悦; 王建龙; 李花子; 施汉昌; 竺建荣

2001-01-01

A strain of yeast, which can endure high osmotic pressure, is employed for the sensitive material of the microbial BOD sensor. Two immobilization methods are used, I.e. Calcium alginate gel be ads and PV A gel beads. The results show that the PVA gel beads is better. The influences of osmosis and heavy metal ions on the yeast entrapped in the PVA gel beads are also studied in the experiment.

Electricity generation using white and red wine lees in air cathode microbial fuel cells

Science.gov (United States)

Pepe Sciarria, Tommy; Merlino, Giuseppe; Scaglia, Barbara; D'Epifanio, Alessandra; Mecheri, Barbara; Borin, Sara; Licoccia, Silvia; Adani, Fabrizio

2015-01-01

Microbial fuel cell (MFC) is a useful biotechnology to produce electrical energy from different organic substrates. This work reports for the first time results of the application of single chamber MFCs to generate electrical energy from diluted white wine (WWL) and red wine (RWL) lees. Power obtained was of 8.2 W m-3 (262 mW m-2; 500 Ω) and of 3.1 W m-3 (111 mW m-2; 500Ω) using white and red wine lees, respectively. Biological processes lead to a reduction of chemical oxygen (TCOD) and biological oxygen demand (BOD5) of 27% and 83% for RWL and of 90% and 95% for WWL, respectively. These results depended on the degradability of organic compounds contained, as suggest by BOD5/TCOD of WWL (0.93) vs BOD5/TCOD of RWL (0.33), and to the high presence of polyphenols in RWL that inhibited the process. Coulombic efficiency (CE) of 15 ± 0%, for WWL, was in line with those reported in the literature for other substrates, i.e. CE of 14.9 ± 11.3%. Different substrates led to different microbial consortia, particularly at the anode. Bacterial species responsible for the generation of electricity, were physically connected to the electrode, where the direct electron transfer took place.

Characterization and treatment of Denizli landfill leachate using anaerobic hybrid/aerobic CSTR systems.

Science.gov (United States)

Ağdağ, Osman Nuri

2011-01-01

Leachate generated in municipal solid waste landfill contains large amounts of organic and inorganic contaminants. In the scope of the study, characterization and anaerobic/aerobic treatability of leachate from Denizli (Turkey) Sanitary Landfill were investigated. Time-based fluctuations in characteristics of leachate were monitored during a one-year period. In characterization study; chemical oxygen demand (COD), biochemical oxygen demand (BOD) dissolved oxygen, temperature, pH, alkalinity, volatile fatty acids, total nitrogen, NH4-N, BOD5/COD ratio, suspended solid, inert COD, anaerobic toxicity assay and heavy metals concentrations in leachate were monitored. Average COD, BOD and NH4-N concentration in leachate were measured as 18034 mg/l, 11504 mg/l and 454 mg/l, respectively. Generally, pollution parameters in leachate were higher in summer and relatively lower in winter due to dilution by precipitation. For treatment of leachate, two different reactors, namely anaerobic hybrid and aerobic completely stirred tank reactor (CSTR) having effective volumes of 17.7 and 10.5 litres, respectively, were used. After 41 days of start-up period, leachate was loaded to hybrid reactor at 10 different organic loading rates (OLRs). OLR was increased by increasing COD concentrations. COD removal efficiency of hybrid reactor was carried out at a maximum of 91%. A percentage of 96% of residual COD was removed in the aerobic reactor. NH4-N removal rate in CSTR was quite high. In addition, high methane content was obtained as 64% in the hybrid reactor. At the end of the study, after 170 operation days, it can be said that the hybrid reactor and CSTR were very effective for leachate treatment.

THE EFFECT OF INFLUENT CONCENTRATION AND HYDRAULIC LOADING RATE (HLR TO BOD AND COD REMOVAL ON ARTIFICIAL DOMESTIC WASTEWATER TREATMENT (GREY WATER USING UASB REACTOR

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Syafrudin Syafrudin

2014-05-01

Full Text Available Upflow anaerobic sludge blanket (UASB reactor is one of anaerobic biological treatment was develop in late 1970’s. UASB reactor is suitable for the tropic areas because it has a high temperature about 20°-30°C. Domestic wastewater is divided into two types, namely black water and grey water. But in this case used domestic grey water. Grey water is household wastewater from showers, sinks and kitchen. Grey water has a total 75% of the domestic wastewater volume. The research was conducted in laboratory scale. This study performed a variation of Hydraulic Loading Rate (HLR and the influent concentration. There were 25 reactors include 5 variations of influent concentration and 5 Hydraulic Loading Rate’s (HLR variation. The research could asses BOD5 and COD removal with treatment in UASB. Efficiency of BOD5 removal by varying the influent concentration and HLR was about 38%-75% and COD was about 40%-77%. The lower concentration could be increase efficiency BOD5 and COD removal. Influent concentration optimum occurred when middle concentration was about 840 mg/L COD and HLR optimum was 0,05 m3/m2/hour.

Fungal chitosan production from potato processing wastewater and its characterization

International Nuclear Information System (INIS)

Khalaf, S.A.; Khalaf, M.A.

2005-01-01

Potato processing wastewater (PPW) was collected and analyzed for biological oxygen demand BOD, chemical oxygen demand (COD), total suspended solids (TSS), total nitrogen and starch content. A fungal strain of Aspergillus niger treated with ultraviolet (UV) radiation was evaluated for its ability to produce chitosan from PPW. Active UV-irradiated isolate, coded A. niger UV-2, was able to reduce COD by about 86.15% with over productivity of chitosan of 1630 mgl -1 after 5 days of its cultivation in PPW. Extractable chitosan from this isolate had a degree of deacetylation of 88.4% and a molecular weight l.lxlo 5 Da. Also, the extractable chitosan at concentration 600 mgl -1 exhibited the maximum antibacterial activity compared with crab shell chitosan

Assessing the Ecological Relevance of Organic Discharge Limits for Constructed Wetlands by Means of a Model-Based Analysis

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Natalia Donoso

2018-01-01

Full Text Available Polder watercourses within agricultural areas are affected by high chemical oxygen demand (COD and biological oxygen demand (BOD5 concentrations, due to intensive farming activities and runoff. Practical cases have shown that constructed wetlands (CWs are eco-friendly and cost-effective treatment systems which can reduce high levels of organic and nutrient pollution from agricultural discharges. However, accumulated recalcitrant organic matter, originated by in-situ sources or elements of CWs (i.e., plants or microbial detritus, limits the fulfilment of current COD discharge threshold. Thus, to evaluate its relevance regarding rivers ecosystem health preservation, we analysed the response of bio-indicators, the Multimetric Macroinvertebrate Index Flanders (MMIF and the occurrence of organic pollution sensitive taxa towards organic pollutants. For this purpose, statistical models were developed based on collected data in polder watercourses and CWs located in Flanders (Belgium. Results showed that, given the correlation between COD and BOD5, both parameters can be used to indicate the ecological and water quality conditions. However, the variability of the MMIF and the occurrence of sensitive species are explained better by BOD5, which captures a major part of their common effect. Whereas, recalcitrant COD and the interaction among other physico-chemical variables indicate a minor variability on the bio-indicators. Based on these outcomes we suggest a critical re-evaluation of current COD thresholds and moreover, consider other emerging technologies determining organic pollution levels, since this could support the feasibility of the implementation of CWs to tackle agricultural pollution.

Organic pollution of rivers: Combined threats of urbanization, livestock farming and global climate change.

Science.gov (United States)

Wen, Yingrong; Schoups, Gerrit; van de Giesen, Nick

2017-02-23

Organic pollution of rivers by wastewater discharge from human activities negatively impacts people and ecosystems. Without treatment, pollution control relies on a combination of natural degradation and dilution by natural runoff to reduce downstream effects. We quantify here for the first time the global sanitation crisis through its impact on organic river pollution from the threats of (1) increasing wastewater discharge due to urbanization and intensification of livestock farming, and (2) reductions in river dilution capacity due to climate change and water extractions. Using in-stream Biochemical Oxygen Demand (BOD) as an overall indicator of organic river pollution, we calculate historical (2000) and future (2050) BOD concentrations in global river networks. Despite significant self-cleaning capacities of rivers, the number of people affected by organic pollution (BOD >5 mg/l) is projected to increase from 1.1 billion in 2000 to 2.5 billion in 2050. With developing countries disproportionately affected, our results point to a growing need for affordable wastewater solutions.

Organic pollution of rivers: Combined threats of urbanization, livestock farming and global climate change

Science.gov (United States)

Wen, Yingrong; Schoups, Gerrit; van de Giesen, Nick

2017-02-01

Organic pollution of rivers by wastewater discharge from human activities negatively impacts people and ecosystems. Without treatment, pollution control relies on a combination of natural degradation and dilution by natural runoff to reduce downstream effects. We quantify here for the first time the global sanitation crisis through its impact on organic river pollution from the threats of (1) increasing wastewater discharge due to urbanization and intensification of livestock farming, and (2) reductions in river dilution capacity due to climate change and water extractions. Using in-stream Biochemical Oxygen Demand (BOD) as an overall indicator of organic river pollution, we calculate historical (2000) and future (2050) BOD concentrations in global river networks. Despite significant self-cleaning capacities of rivers, the number of people affected by organic pollution (BOD >5 mg/l) is projected to increase from 1.1 billion in 2000 to 2.5 billion in 2050. With developing countries disproportionately affected, our results point to a growing need for affordable wastewater solutions.

ABILITY OF BACTERIAL CONSORTIUM: Bacillus coagulans, Bacilus licheniformis, Bacillus pumilus, Bacillus subtilis, Nitrosomonas sp. and Pseudomonas putida IN BIOREMEDIATION OF WASTE WATER IN CISIRUNG WASTE WATER TREATMENT PLANT

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Ratu SAFITRI

2015-10-01

Full Text Available This study was conducted in order to determine the ability of bacterial consortium: Bacillus coagulans, Bacilus licheniformis, Bacillus pumilus, Bacillus subtilis, Nitrosomonas sp., and Pseudomonas putida in bioremediation of wastewater origin Cisirung WWTP. This study uses an experimental method completely randomized design (CRD, which consists of two treatment factors (8x8 factorial design. The first factor is a consortium of bacteria (K, consisting of 8 level factors (k1, k2, k3, k4, k5, k6, k7, and k8. The second factor is the time (T, consisting of a 7 level factors (t0, t1, t2, t3, t4, t5, t6, and t7. Test parameters consist of BOD (Biochemical Oxygen Demand, COD (Chemical Oxygen Demand, TSS (Total Suspended Solid, Ammonia and Population of Microbes during bioremediation. Data were analyzed by ANOVA, followed by Duncan test. The results of this study showed that the consortium of Bacillus pumilus, Bacillus subtilis, Bacillus coagulans, Nitrosomonas sp., and Pseudomonas putida with inoculum concentration of 5% (k6 is a consortium of the most effective in reducing BOD 71.93%, 64.30% COD, TSS 94.85%, and 88.58% of ammonia.

Use of native aquatic macrophytes in the reduction of organic matter from dairy effluents.

Science.gov (United States)

Queiroz, Rita de Cássia Souza de; Andrade, Rodrigo Santos; Dantas, Isadora Rosário; Ribeiro, Vinícius de Souza; Neto, Luciano Brito Rodrigues; Almeida Neto, José Adolfo de

2017-08-03

Considering the diversity and the unexplored potential of regional aquatic flora, this study aimed to identify and analyze the potential of native aquatic macrophytes to reduce the organic matter of dairy wastewater (DW) using experimental constructed wetlands. The dairy wastewater (DW) had an average chemical oxygen demand (COD) of 7414.63 mg/L and then was diluted to 3133.16 mg/L (D1) and to 2506.53 mg/L (D2). Total solids, COD, temperature, and pH analyses were performed, and the biochemical oxygen demand (BOD) was estimated from the COD values. The best performance in the reduction of the organic matter was observed for Polygonum sp. (87.5% COD and 79.6% BOD) and Eichhornia paniculata (90% COD and 83.7% BOD) at dilution D1, on the 8th day of the experiment. However, the highest total solids removal was observed for Polygonum sp. (32.2%), on the 4th day, at dilution D2. The total solid (TS) concentration has also increased starting from the 8th day of the experiment was observed which may have been due to the development of mosquito larvae and their mechanical removal by sieving, thus changing the steady state of the experimental systems. The macrophytes Polygonum sp. and E. paniculata were considered suitable for the reduction of organic matter of DW using constructed wetlands.

Tannery Effluent Treatment by Yeast Species Isolates from Watermelon

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Stanley Irobekhian Reuben Okoduwa

2017-02-01

Full Text Available The quest for an effective alternative means for effluent treatment is a major concern of the modern-day scientist. Fungi have been attracting a growing interest for the biological treatment of industrial wastewater. In this study, Saccharomycescerevisiae and Torulasporadelbrueckii were isolated from spoiled watermelon and inoculated into different concentrations of effluent. The inoculants were incubated for 21-days to monitor the performance of the isolates by measurement of biochemical oxygen demand (BOD, chemical oxygen demand (COD, nitrates, conductivity, phosphates, sulphates and turbidity. The results showed that Saccharomycescerevisiae had the highest percentage decrease of 98.1%, 83.0%, 60.7%, 60.5%, and 54.2% for turbidity, sulphates, BOD, phosphates and COD, respectively, of the tannery effluent. Torulasporadelbrueckii showed the highest percentage decrease of 92.9%, 90.6%, and 61.9% for sulphates, COD, and phosphates, respectively, while the syndicate showed the highest percentage reduction of 87.4% and 70.2% for nitrate and total dissolve solid (TDS, respectively. The least percentage decrease was displayed by syndicate organisms at 51.2%, 48.1% and 40.3% for BOD, COD and conductivity, respectively. The study revealed that Saccharomycescerevisiae and Torulasporadelbrueckii could be used in the biological treatment of tannery-effluent. Hence, it was concluded that the use of these organisms could contribute to minimizing the adverse environmental risks and health-hazards associated with the disposal of untreated tannery-effluents.

Combination of ozonation, activated carbon, and biological aerated filter for advanced treatment of dyeing wastewater for reuse.

Science.gov (United States)

Zou, Xiao-Ling

2015-06-01

Laboratorial scale experiments were performed to investigate and evaluate the performance and removal characteristics of organics, color, and genotoxicity by an integrated process including ozonation, activated carbon (AC), and biological aerated filter (BAF) for recycling biotreated dyeing wastewater (BTDW) collected from a cotton textile factory. Influent chemical oxygen demand (COD) in the range of 156 - 252 mg/L, 5-day biochemical oxygen demand (BOD5) of 13.5 - 21.7 mg/L, and color of 58 - 76° were observed during the 20-day continuous operation. Outflows with average COD of 43 mg/L, BOD5 of 6.6 mg/L, and color of 5.6° were obtained after being decontaminated by the hybrid system with ozone dosage of 0.25 mg O3applied/mg COD0, 40 min ozonation contact time, 30 min hydraulic retention time (HRT) for AC treatment, and 2.5 h HRT for BAF treatment. More than 82 % of the genotoxicity of BTDW was eliminated in the ozonation unit. The genotoxicity of the BAF effluent was less than 1.33 μg 4-nitroquinoline-N-oxide/L. Ozonation could change the organics molecular structures, destroy chromophores, increase the biodegradability, and obviously reduce the genotoxicity of BTDW. Results showed that the combined process could guarantee water reuse with high quality.

Application of regression model on stream water quality parameters

International Nuclear Information System (INIS)

Suleman, M.; Maqbool, F.; Malik, A.H.; Bhatti, Z.A.

2012-01-01

Statistical analysis was conducted to evaluate the effect of solid waste leachate from the open solid waste dumping site of Salhad on the stream water quality. Five sites were selected along the stream. Two sites were selected prior to mixing of leachate with the surface water. One was of leachate and other two sites were affected with leachate. Samples were analyzed for pH, water temperature, electrical conductivity (EC), total dissolved solids (TDS), Biological oxygen demand (BOD), chemical oxygen demand (COD), dissolved oxygen (DO) and total bacterial load (TBL). In this study correlation coefficient r among different water quality parameters of various sites were calculated by using Pearson model and then average of each correlation between two parameters were also calculated, which shows TDS and EC and pH and BOD have significantly increasing r value, while temperature and TDS, temp and EC, DO and BL, DO and COD have decreasing r value. Single factor ANOVA at 5% level of significance was used which shows EC, TDS, TCL and COD were significantly differ among various sites. By the application of these two statistical approaches TDS and EC shows strongly positive correlation because the ions from the dissolved solids in water influence the ability of that water to conduct an electrical current. These two parameters significantly vary among 5 sites which are further confirmed by using linear regression. (author)

Studies on the kinetics and intraparticle diffusivities of BOD, colour ...

African Journals Online (AJOL)

EJIRO

The kinetics and intraparticle diffusivities of BOD, TSS and colour reduction from palm oil mill effluent (POME) using ... discharged (Asia et al., 2006). The oil palm ... biological treatment methods, anaerobic digestion is often the most ... and lower capital cost. ... was then rinsed with distilled water and air dried, ready for the.

Effect of abattoir wastes on the water quality of Aleto River in the ...

African Journals Online (AJOL)

The effects of abattoir effluent on the water quality parameters, pH, dissolved oxygen, nitrate (NO3), phosphate (PO4), sulphate (SO4), hardness, conductivity, faecal coliform and the biochemical oxygen demand (BOD), of the receiving surface water of Aleto River in River State (Niger Delta, Nigeria) was monitored monthly ...

Zależność bodźcowości ciśnienia od cyrkulacji atmosferycznej w Warszawie

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Katarzyna Rozbicka

2016-09-01

Full Text Available W pracy zbadano: czasowy rozkład ciśnienia atmosferycznego, bodźcowe oddziaływanie ciśnienia atmosferycznego o wartościach wyższych od 1015 hPa lub niższych od 985 hPa. Wyznaczono częstość i prawdopodobieństwo wystąpienia ciśnienia o oddziaływaniu bodźcowym oraz zanalizowano zależność zmian międzydobowych ciśnienia od typów cyrkulacji atmosferycznej według klasyfikacji Lityńskiego. Do obliczeń wykorzystano cogodzinne wartości ciśnienia atmosferycznego pochodzące ze stacji Ursynów SGGW z okresu 2011–2015. Na podstawie badań stwierdzono, że ciśnienie atmosferyczne o oddziaływaniu bodźcowym w Warszawie może wystąpić w każdym miesiącu z prawdopodobieństwem od 0,2% do 19,1%, w przypadku ciśnienia o wartościach wyższych niż 1015 hPa oraz od 0,1 do 3,4%, w przypadku ciśnienia niższego od 985 hPa, z wyjątkiem czerwca i sierpnia. Zmiany międzydobowe ciśnienia atmosferycznego mogą osiągać około 24 hPa, a częstość występowania bodźców „silnych” wywołanych tymi zmianami wyniosła w poszczególnych miesiącach od 1% do 16%, natomiast bodźców „bardzo silnych” od 2% do 8%. Spośród sytuacji synoptycznych największe znaczenie dla bodźcowości zmian ciśnienia mają sytuacje cyklonalne: szczególnie przy adwekcji powietrza z sektora północno-zachodniego (NWC.

Bioremediation of Synthetic and Industrial Effluents by Aspergillus niger Isolated from Contaminated Soil Following a Sequential Strategy.

Science.gov (United States)

Gulzar, Tahsin; Huma, Tayyaba; Jalal, Fatima; Iqbal, Sarosh; Abrar, Shazia; Kiran, Shumaila; Nosheen, Sofia; Hussain, Waqar; Rafique, Muhammad Asim

2017-12-16

The present study aimed to assess and compare the ability to remediate synthetic textile and industrial wastewaters by Fenton treatment, a biological system and sequential treatments using Aspergillus niger ( A. niger ). All studied treatments were found to be effective in decolorization of the effluents under study. Fenton treatment followed by A. niger showed excellent potential for the maximum decolorization of the synthetic and industrial effluents under study. The effectiveness of sequential treatment was evaluated by water quality parameters such as total organic carbon (TOC), Biological Oxygen Demand (BOD5) and Chemical Oxygen Demand (COD) before and after each treatment. The results indicated that A. niger is an effective candidate for detoxification of textile wastewaters.

Bioremediation of Synthetic and Industrial Effluents by Aspergillus niger Isolated from Contaminated Soil Following a Sequential Strategy

Directory of Open Access Journals (Sweden)

Tahsin Gulzar

2017-12-01

Full Text Available The present study aimed to assess and compare the ability to remediate synthetic textile and industrial wastewaters by Fenton treatment, a biological system and sequential treatments using Aspergillus niger (A. niger. All studied treatments were found to be effective in decolorization of the effluents under study. Fenton treatment followed by A. niger showed excellent potential for the maximum decolorization of the synthetic and industrial effluents under study. The effectiveness of sequential treatment was evaluated by water quality parameters such as total organic carbon (TOC, Biological Oxygen Demand (BOD5 and Chemical Oxygen Demand (COD before and after each treatment. The results indicated that A. niger is an effective candidate for detoxification of textile wastewaters.

Performance Evaluation of Anaerobic-Aerobic Treatment for the Wastewater of Potato Processing Industry: A Case Study of a Local Chips Factory

International Nuclear Information System (INIS)

Haydar, S.; Nadeem, O.

2014-01-01

A study was conducted to assess the performance of anaerobic-aerobic treatment system of a local potato processing industry. The wastewater treatment plant (WWTP) consisted of primary treatment, upflow anaerobic sludge blanket (UASB), activated sludge process (ASP) and secondary clarifier. The study analyzed the physical, chemical and biochemical parameters of the influent (raw sewage) as well as the effluent from each component of the plant. Grab wastewater samples were collected on weekly basis and analyzed for the pH, settleable solids (SS), total suspended solids (TSS), total dissolved solids (TDS), biochemical oxygen demand (BOD), and chemical oxygen demand (COD). Study revealed that mean influent wastewater concentrations of TSS, TDS, SS, BOD and COD were 840 mg/L, 2,396 mg/L and 18.7 mL/L, 2,186 mg/L and 3,679 mg/L, respectively. The mean percentage removal efficiency in UASB for TSS, BOD and COD was found to be 56%, 61 % and 51%, respectively. The mean percentage removal efficiency in activated sludge system for TSS, BOD and COD was found to be 70%, 57% and 48%, respectively. The mean percentage removal efficiency of combined anaerobic-aerobic system for TSS, BOD and COD was found to be 93%, 90% and 80%, respectively. The mean effluent concentrations of TSS, BOD and COD were 52 mg/L, 197 mg/L and 784 mg/L, respectively. The effluent from WWTP satisfied NEQS for TSS (200 mg/L) while NEQS for BOD (80 mg/L) and COD (150 mg/L) were not satisfied. Some operational problems, responsible for inadequate efficiencies of the plant components, were identified and solutions were suggested for these problems. (author)

Sediment oxygen demand of wetlands in the oil sands region of northeastern Alberta

International Nuclear Information System (INIS)

Slama, C.; Gardner Costa, J.; Ciborowski, J.

2010-01-01

Sediment oxygen demand (SOD) can significantly influence the dissolved oxygen concentrations in shallow water bodies. This study discussed the types of sediments used to reclaim wetlands and their influence on SOD, successional processes, and ecosystem trajectories. The study hypothesized that oil sands process material (OSPM) affected wetlands would support cyanobacterial biofilms as opposed to submergent macrophytes as a result of insufficient phosphorus levels. SOD was assessed by monitoring dissolved oxygen concentrations within domes placed on the sediment surface for a 3-hour period. Gas flux and composition analyses were used to quantify the biological SOD components. Chemical SOD components were then determined by subtraction. Concentrations of phosphorus bioavailable to the macrophytes were estimated using plant root simulator probes. The study showed that OSPM wetlands exhibited higher chemical SOD and SOD than reference wetlands, and supported benthic biofilms as opposed to the submergent macrophyte communities typically found in northeastern Alberta wetlands.

Sediment oxygen demand of wetlands in the oil sands region of northeastern Alberta

Energy Technology Data Exchange (ETDEWEB)

Slama, C.; Gardner Costa, J.; Ciborowski, J. [Windsor Univ., ON (Canada)

2010-07-01

Sediment oxygen demand (SOD) can significantly influence the dissolved oxygen concentrations in shallow water bodies. This study discussed the types of sediments used to reclaim wetlands and their influence on SOD, successional processes, and ecosystem trajectories. The study hypothesized that oil sands process material (OSPM) affected wetlands would support cyanobacterial biofilms as opposed to submergent macrophytes as a result of insufficient phosphorus levels. SOD was assessed by monitoring dissolved oxygen concentrations within domes placed on the sediment surface for a 3-hour period. Gas flux and composition analyses were used to quantify the biological SOD components. Chemical SOD components were then determined by subtraction. Concentrations of phosphorus bioavailable to the macrophytes were estimated using plant root simulator probes. The study showed that OSPM wetlands exhibited higher chemical SOD and SOD than reference wetlands, and supported benthic biofilms as opposed to the submergent macrophyte communities typically found in northeastern Alberta wetlands.

Determination of Biological Treatability Processes of Textile Wastewater and Implementation of a Fuzzy Logic Model

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Harun Akif Kabuk

2015-01-01

Full Text Available This study investigated the biological treatability of textile wastewater. For this purpose, a membrane bioreactor (MBR was utilized for biological treatment after the ozonation process. Due to the refractory organic contents of textile wastewater that has a low biodegradability capacity, ozonation was implemented as an advanced oxidation process prior to the MBR system to increase the biodegradability of the wastewater. Textile wastewater, oxidized by ozonation, was fed to the MBR at different hydraulic retention times (HRT. During the process, color, chemical oxygen demand (COD, and biochemical oxygen demand (BOD removal efficiencies were monitored for 24-hour, 12-hour, 6-hour, and 3-hour retention times. Under these conditions, 94% color, 65% COD, and 55% BOD removal efficiencies were obtained in the MBR system. The experimental outputs were modeled with multiple linear regressions (MLR and fuzzy logic. MLR results suggested that color removal is more related to COD removal relative to BOD removal. A surface map of this issue was prepared with a fuzzy logic model. Furthermore, fuzzy logic was employed to the whole modeling of the biological system treatment. Determination coefficients for COD, BOD, and color removal efficiencies were 0.96, 0.97, and 0.92, respectively.

Phytoremediation Potential of Vetiver System Technology for Improving the Quality of Palm Oil Mill Effluent

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Negisa Darajeh

2014-01-01

Full Text Available Palm oil mill effluent (POME, a pollutant produced by the palm oil industry, was treated by the Vetiver system technology (VST. This technology was applied for the first time to treat POME in order to decrease biochemical oxygen demand (BOD and chemical oxygen demand (COD. In this study, two different concentrations of POME (low and high were treated with Vetiver plants for 2 weeks. The results showed that Vetiver was able to reduce the BOD up to 90% in low concentration POME and 60% in high concentration POME, while control sets (without plant only was able to reduce 15% of BOD. The COD reduction was 94% in low concentration POME and 39% in high concentration POME, while control just shows reduction of 12%. Morphologically, maximum root and shoot lengths were 70 cm, the number of tillers and leaves was 344 and 86, and biomass production was 4.1 kg m−2. These results showed that VST was effective in reducing BOD and COD in POME. The treatment in low concentration was superior to the high concentration. Furthermore, biomass of plant can be considered as a promising raw material for biofuel production while high amount of biomass was generated in low concentration of POME.

Serum Tumor Necrosis Factor-alpha associates with Myocardial Oxygen Demand and Exercise Tolerance in Postmenopausal Women.

Science.gov (United States)

Carter, Stephen J; Bryan, David R; Neumeier, William H; Glasser, Stephen P; Hunter, Gary R

2018-01-01

The functional implications of serum tumor necrosis factor-alpha (TNF-α), a marker of oxidative stress, on hemodynamic parameters at rest and during physical exertion are unclear. The aims of this investigation were to examine the independent associations of TNF-α on myocardial oxygen demand at rest and during submaximal exercise, while also evaluating the association of TNF-α on exercise tolerance. Forty, postmenopausal women, provided blood samples and completed a modified-Balke protocol to measure maximal oxygen uptake (VO 2max ). Large artery compliance was measured by pulse contour analyses while rate-pressure product (RPP), an index of myocardial oxygen demand, was measured at rest and during two submaximal workloads (i.e., ≈55% and ≈75% VO 2max ). RPP was calculated by dividing the product of heart rate and systolic blood pressure (via auscultation) by 100. Exercise tolerance corresponded with the cessation of the graded exercise test. During higher-intensity exertion, ≈75% VO 2max , multiple linear regression revealed a positive association ( r = 0.43; p = 0.015) between TNF-α and RPP while adjusting for maximal heart rate, VO 2max , large artery compliance, and percent body fat. Path analyses revealed a significant indirect effect of large artery compliance on exercise tolerance through TNF-α, β = 0.13, CI [0.03, 0.35], indicating greater levels of TNF-α associated with poorer exercise tolerance. These data suggest TNF-α independently associates with myocardial oxygen demand during physical exertion, thus highlighting the utility of higher-intensity efforts to expose important phenomena not apparent at rest. TNF-α also appears to be indirectly associated with the link between large artery compliance and exercise tolerance.

A Preliminary Study of Water Quality Index in Terengganu River Basin, Malaysia

International Nuclear Information System (INIS)

Suratman, S.; Mohd, S.M.I.; Hee, Y.Y.; Bedurus, E.A.; Latif, M.T.

2015-01-01

The Malaysian Department of Environment-Water Quality Index (DOE-WQI) was determined for the Terengganu River basin which is located at the coastal water of the southern South China Sea between July and October 2008. Monthly samplings were carried out at ten sampling stations within the basin. Six parameters listed in DOE-WQI were measured based on standard methods: pH, dissolved oxygen (DO), biochemical oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS) and ammonical nitrogen (AN). The results indicated the impact of various anthropogenic activities which contribute to high values of BOD, COD, TSS and AN at middle and downstream stations, as compared with the upstream of the basin. The reverses were true for the pH and DO values. The DOE-WQI ranged from 71.5-94.6 % (mean 86.9 %), which corresponded to a classification status range from slightly polluted to clean. With respect to the Malaysia National Water Quality Standards (NWQS), the level of most of the parameters measured remained at Class I which is suitable for the sustainable conservation of the natural environment, for water supply without treatment and as well as for very sensitive aquatic species. It is suggested that monitoring should be carried out continuously for proper management of this river basin. (author)

Studies on the kinetics and intraparticle diffusivities of BOD, colour ...

African Journals Online (AJOL)

Therefore, this study reveals that boiler fly ash can effectively be used as an adsorbent for POME treatment and also established the kinetic and mechanisms of the sorption process. Also, the results of this study could serve as effective design parameters for a treatment plant to further reduce BOD, colour and TSS from ...

Effect of Lakhara chemical power station (LPTS) effluents on the river Indus water quality

International Nuclear Information System (INIS)

Mahar, R.B.; Memon, H.M.; Khushwar, M.Y.

2000-01-01

The variation of the quality of river Indus water with respect to the seasonal changes, discharge of water and dilution with the effluents of Lakhra Thermal Power Station (LTPS), has been monitored. The studies were focussed on the river Indus water quality before and after mixing the effluents of the power station. The samples were collected monthly from the representative locations of the river Indus, and analyzed for the residues (total, filterable, non-filterable, volatile and fixed), pH, temperature (air and water), conductance, chloride, hardness, alkalinity, dissolved oxygen (DO), chemical oxygen demand (COD), biochemical oxygen demand (BOD) /sub 5/- nitrate, phosphate, sulfate, ammonia, ammonium, silicates, magnesium, potassium, calcium and sodium. The results have been compared with the permissible limits of ECC (European Economic Community) standards for drinking and surface water. (author)

Effect of ozonation on microbial fish pathogens, ammonia, nitrate, nitrite, and bod in simulated reuse hatchery water

Energy Technology Data Exchange (ETDEWEB)

Colberg, P.J.; Lingg, A.J.

1978-10-01

The effectiveness of ozone for eliminating fish pathogens and reducing nitrite, ammonia, and BOD associated with reuse hatchery systems was evaluated. Comparative survival rates of four bacterial fish pathogens and a bacterium-protozoan population during batch and continuous flow ozonation indicated a specific microbial ozone demand during batch treatment and 99% mortality of pathogens during continuous flow treatment. Oxidation of carbon and nitrite by ozone was rapid at low ozone concentrations; carbon and ammonia oxidation rates were pH dependent. The oxidation capacity of ozone in water was greatest at elevated pH even though lower ozone concentrations were used. Ozone treatment appears to be successful for disinfecting hatchery makeup water for recycling. However, the economics of such treatment are yet to be determined. (10 graphs, 28 references, 1 table)

Environmental applications of manometric respirometric methods

Energy Technology Data Exchange (ETDEWEB)

Roppola, K.

2009-07-01

In this work a manometric respirometric measuring system was applied to practical environmental cases related to wastewater management and biodegradation studies of oil-contaminated soils and materials used in landfill structures. Pollution of groundwater, surface water and soils is a worldwide problem. Therefore, tests simulating the biodegradation behaviour of organic compounds in water media and soils have become increasingly important. Respirometric methods provide direct measurement of the oxygen consumed by micro-organisms in biodegradation processes from an air or oxygen-enriched environment in a closed vessel. Biochemical oxygen demand (BOD) is a crucial environmental parameter used to measure the quality of water and treatment results in wastewater. Generally, BOD is measured with standardised methods, which are usually time-consuming as well as laborious. In this work the manometric respirometric test was compared with conventional BOD tests by determining the BOD of pulp and paper mills as well as domestic wastewater samples. The effect of different factors such as type, amount and pre-treatment of inoculum and the effect of dilution of a sample on the BOD values were also tested. A right dilution was noticed to be the most significant factor affecting the BOD values of the industrial wastewater samples. The mathematic estimation of the BOD7 values from the respirometric data was proved to work reliably after a 2-3 day incubation period. Characterisation of organic fractions of the pulp and paper mill wastewater was carried out with methods including filtration, long term BOD measurements and COD analyses. The most significant observation in characterisation analyses was that a remarkable part of the detected oxygen demand was consumed for the biotransformation of biodegradable fractions into new inert decomposition products, not only for mineralisation of the biodegradable COD fraction. Biodegradation behaviour of the peat samples with different

Burden of disease calculation, cost of illness analysis and demand ...

African Journals Online (AJOL)

The paper introduces the demand for death for Activities of Daily Living (ADL) measured disability as being pioneered by Igberaese and co-workers, as a way of eliminating the BoD and CoI once and for all. It makes DALY only equal to YLL, as YLD approaches zero. DALY will simply be the number of years of life lost due to ...

Soil aquifer treatment of artificial wastewater under saturated conditions

KAUST Repository

Essandoh, H. M K; Tizaoui, Chedly; Mohamed, Mostafa H A; Amy, Gary L.; Brdjanovic, Damir

2011-01-01

A 2000 mm long saturated laboratory soil column was used to simulate soil aquifer treatment under saturated conditions to assess the removal of chemical and biochemical oxygen demand (COD and BOD), dissolved organic carbon (DOC), nitrogen

Drawer compacted sand filter: a new and innovative method for on-site grey water treatment.

Science.gov (United States)

Assayed, Almoayied; Chenoweth, Jonathan; Pedley, Steven

2014-01-01

In this paper, results ofa new sand filter design were presented. The drawer compacted sand filter (DCSF) is a modified design for a sand filter in which the sand layer is broken down into several layers, each of which is 10 cm high and placed in a movable drawer separated by a 10 cm space. A lab-scale DCSF was designed and operated for 330 days fed by synthetic grey water. The response of drawer sand filters to variable hydraulic and organic loading rates (HLR and OLR) in terms of biological oxygen demand (BODs), chemical oxygen demand (COD), total suspended solids (TSS), pH, electrical conductivity and Escherichia coli reductions were evaluated. The HLR was studied by increasing from 72 to 142 L m(-2) day(-1) and OLR was studied by increasing it from 23 to 30 g BOD5 m(-2) day(-1) while keeping the HLR constant at 142 L m(-2) day(-1). Each loading regime was applied for 110 days. Results showed that DCSF was able to remove >90% of organic matter and total suspended solids for all doses. No significant difference was noticed in terms of overall filter efficiency between different loads for all parameters. Significant reduction in BOD5 and COD (P water was drained through the third drawer in all tested loads. The paper concludes that DCSF would be appropriate for use in dense urban areas as its footprint is small and is appropriate for a wide range of users because of its convenience and low maintenance requirements.

Modelling soil dust aerosol in the Bodélé depression during the BoDEx campaign

Science.gov (United States)

Tegen, I.; Heinold, B.; Todd, M.; Helmert, J.; Washington, R.; Dubovik, O.

2006-09-01

We present regional model simulations of the dust emission events during the Bodélé Dust Experiment (BoDEx) that was carried out in February and March 2005 in Chad. A box model version of the dust emission model is used to test different input parameters for the emission model, and to compare the dust emissions computed with observed wind speeds to those calculated with wind speeds from the regional model simulation. While field observations indicate that dust production occurs via self-abrasion of saltating diatomite flakes in the Bodélé, the emission model based on the assumption of dust production by saltation and using observed surface wind speeds as input parameters reproduces observed dust optical thicknesses well. Although the peak wind speeds in the regional model underestimate the highest wind speeds occurring on 10-12 March 2005, the spatio-temporal evolution of the dust cloud can be reasonably well reproduced by this model. Dust aerosol interacts with solar and thermal radiation in the regional model; it is responsible for a decrease in maximum daytime temperatures by about 5 K at the beginning the dust storm on 10 March 2005. This direct radiative effect of dust aerosol accounts for about half of the measured temperature decrease compared to conditions on 8 March. Results from a global dust model suggest that the dust from the Bodélé is an important contributor to dust crossing the African Savannah region towards the Gulf of Guinea and the equatorial Atlantic, where it can contribute up to 40% to the dust optical thickness.

An Investigation Into The Water Quality Of Buriganga - A River Running Through Dhaka

Directory of Open Access Journals (Sweden)

Shaikh Sayed Ahammed

2015-08-01

Full Text Available Buriganga river is used for bathing drinking irrigation and industrial purposes and is considered to be the lifeline of Dhaka city. The water quality of Buriganga has become a matter of concern due to serious levels of pollution. The objective of the study was to determine the water quality of the selected section of Buriganga river which passes through Dhaka city. The water quality parameters were sampled during different seasons summer winter and autumn and in 10 different sampling points along the river along the banks of the Buriganga River. The water quality parameters studied for this study were dissolved oxygen DO biochemical oxygen demand BOD chemical oxygen demand COD pH turbidity conductivity total dissolved solids TDS nitrate and phosphate. The results showed that DO BOD COD TDS turbidity nitrate and phosphate are at an alarming level and a discussion on the possible sources of the pollution are presented.

Effects of acute and 2-hour postphysical activity on the estimation of body fat made by the bod pod.

Science.gov (United States)

Harrop, Bradley J; Woodruff, Sarah J

2015-06-01

The Bod Pod has been found to be reliable/valid against several criterion methods, including hydrostatic weighing and dual-energy x-ray absorptiometry, and under different conditions, such as clothing, dehydrated states, and body temperature changes. However, questions remain regarding the effects of an acute bout of exercise. Therefore, the purpose was to determine the effects of an acute bout of exercise on the estimations made by the Bod Pod. Participants (15 men and 22 women) were of age 18-27 years and were currently exercising. Baseline Bod Pod measures were completed followed by a 30-minute cycling trial at 75% of maximum heart rate. Bod Pod measures were taken immediately after exercise and 2 hours after exercise. Differences between men and women were found at baseline between height (p temperature (p temperature (p estimate of %BF, and continues to affect the prediction 2 hours after exercise in women.

Sulfamethoxazole abatement by photo-Fenton

International Nuclear Information System (INIS)

Gonzalez, Oscar; Sans, Carme; Esplugas, Santiago

2007-01-01

The objective of this work was to study the abatement of 200 mg L -1 sulfamethoxazole (SMX) solution by means of photo-Fenton process. Biodegradability of the treated solutions was followed by the ratio biochemical oxygen demand at five days/chemical oxygen demand (BOD 5 /COD) and toxicity by Microtox[reg] and inhibition tests. Experiments with different initial concentration of H 2 O 2 were carried out. The initial amount of Fe 2+ and pH of the solution were set at 10 mg L -1 and 2.8 respectively. The temperature of the reactor was kept constant in all the experiments (25 ± 0.8 deg. C). Photo-Fenton process is thought to be a successful treatment step to improve the biodegradability of wastewater containing SMX. The complete antibiotic removal was achieved for a H 2 O 2 dose over 300 mg L -1 . Biodegradability (BOD 5 /COD) rose from zero (SMX solution) to values higher than 0.3 (treated solutions). Toxicity and inhibition tests pointed out in the same direction: oxidized intermediates for initial H 2 O 2 dose over 300 mg L -1 showed no toxicity effects on pure bacteria and no inhibition on activated sludge activity

Source Apportionment of Annual Water Pollution Loads in River Basins by Remote-Sensed Land Cover Classification

Directory of Open Access Journals (Sweden)

Yi Wang

2016-08-01

Full Text Available In this study, in order to determine the efficiency of estimating annual water pollution loads from remote-sensed land cover classification and ground-observed hydrological data, an empirical model was investigated. Remote sensing data imagery from National Oceanic and Atmospheric Administration (NOAA Advanced Very High Resolution Radiometer were applied to an 11 year (1994–2004 water quality dataset for 30 different rivers in Japan. Six water quality indicators—total nitrogen (TN, total phosphorus (TP, biochemical oxygen demand (BOD, chemical oxygen demand (COD, and dissolved oxygen (DO—were examined by using the observed river water quality data and generated land cover map. The TN, TP, BOD, COD, and DO loads were estimated for the 30 river basins using the empirical model. Calibration (1994–1999 and validation (2000–2004 results showed that the proposed simulation technique was useful for predicting water pollution loads in the river basins. We found that vegetation land cover had a larger impact on TP export into all rivers. Urban areas had a very small impact on DO export into rivers, but a relatively large impact on BOD and TN export. The results indicate that the application of land cover data generated from the remote-sensed imagery could give a useful interpretation about the river water quality.

Treatment of oilfield produced water by anaerobic process coupled with micro-electrolysis.

Science.gov (United States)

Li, Gang; Guo, Shuhai; Li, Fengmei

2010-01-01

Treatment of oilfield produced water was investigated using an anaerobic process coupled with micro-electrolysis (ME), focusing on changes in chemical oxygen demand (COD) and biodegradability. Results showed that COD exhibited an abnormal change in the single anaerobic system in which it increased within the first 168 hr, but then decreased to 222 mg/L after 360 hr. The biological oxygen demand (five-day) (BODs)/COD ratio of the water increased from 0.05 to 0.15. Hydrocarbons in the wastewater, such as pectin, degraded to small molecules during the hydrolytic acidification process. Comparatively, the effect of ME was also investigated. The COD underwent a slight decrease and the BOD5/COD ratio of the water improved from 0.05 to 0.17 after ME. Removal of COD was 38.3% under the idealized ME conditions (pH 6.0), using iron and active carbon (80 and 40 g/L, respectively). Coupling the anaerobic process with ME accelerated the COD removal ratio (average removal was 53.3%). Gas chromatography/mass spectrometry was used to analyze organic species conversion. This integrated system appeared to be a useful option for the treatment of water produced in oilfields.

Characterization of water quality and simulation of temperature, nutrients, biochemical oxygen demand, and dissolved oxygen in the Wateree River, South Carolina, 1996-98

Science.gov (United States)

Feaster, Toby D.; Conrads, Paul

2000-01-01

In May 1996, the U.S. Geological Survey entered into a cooperative agreement with the Kershaw County Water and Sewer Authority to characterize and simulate the water quality in the Wateree River, South Carolina. Longitudinal profiling of dissolved-oxygen concentrations during the spring and summer of 1996 revealed dissolved-oxygen minimums occurring upstream from the point-source discharges. The mean dissolved-oxygen decrease upstream from the effluent discharges was 2.0 milligrams per liter, and the decrease downstream from the effluent discharges was 0.2 milligram per liter. Several theories were investigated to obtain an improved understanding of the dissolved-oxygen dynamics in the upper Wateree River. Data suggest that the dissolved-oxygen concentration decrease is associated with elevated levels of oxygen-consuming nutrients and metals that are flowing into the Wateree River from Lake Wateree. Analysis of long-term streamflow and water-quality data collected at two U.S. Geological Survey gaging stations suggests that no strong correlation exists between streamflow and dissolved-oxygen concentrations in the Wateree River. However, a strong negative correlation does exist between dissolved-oxygen concentrations and water temperature. Analysis of data from six South Carolina Department of Health and Environmental Control monitoring stations for 1980.95 revealed decreasing trends in ammonia nitrogen at all stations where data were available and decreasing trends in 5-day biochemical oxygen demand at three river stations. The influence of various hydrologic and point-source loading conditions on dissolved-oxygen concentrations in the Wateree River were determined by using results from water-quality simulations by the Branched Lagrangian Transport Model. The effects of five tributaries and four point-source discharges were included in the model. Data collected during two synoptic water-quality samplings on June 23.25 and August 11.13, 1997, were used to calibrate

Electrolysis of polluting wastes: I - Wastewater from a seasoning freeze-drying industry

OpenAIRE

Angelis, Dejanira F. de; Corso, Carlos R.; Bidoia, Ederio D.; Moraes, Peterson B.; Domingos, Roberto N.; Rocha-Filho, Romeu C.

1998-01-01

Wastewater from a seasoning freeze-drying industry was electrolysed to increase its biodegradability. Stainless-steel electrodes were used at 9.09 A/m², for up to 80 min. Conductivity, pH, biochemical (BOD) and chemical (COD) oxygen demands, Daphnia similis acute toxicity bioassays, and bacteria counting through the plate count agar method were determined after different times of electrolysis. The results (e.g. higher BOD and lower COD) showed that the biodegradability of the wastewater was s...

Non-biodegradable landfill leachate treatment by combined process of agitation, coagulation, SBR and filtration

Energy Technology Data Exchange (ETDEWEB)

Abood, Alkhafaji R. [State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan 430074 (China); Thi Qar University, Nasiriyah (Iraq); Bao, Jianguo, E-mail: bjianguo888@126.com [State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan 430074 (China); Du, Jiangkun; Zheng, Dan; Luo, Ye [State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan 430074 (China)

2014-02-15

Highlights: • A novel method of stripping (agitation) was investigated for NH{sub 3}-N removal. • PFS coagulation followed agitation process enhanced the leachate biodegradation. • Nitrification–denitrification achieved by changing operation process in SBR treatment. • A dual filter of carbon-sand is suitable as a polishing treatment of leachate. • Combined treatment success for the complete treatment of non-biodegradable leachate. - Abstract: This study describes the complete treatment of non-biodegradable landfill leachate by combined treatment processes. The processes consist of agitation as a novel stripping method used to overcome the ammonia toxicity regarding aerobic microorganisms. The NH{sub 3}-N removal ratio was 93.9% obtained at pH 11.5 and a gradient velocity (G) 150 s{sup −1} within a five-hour agitation time. By poly ferric sulphate (PFS) coagulation followed the agitation process; chemical oxygen demand (COD) and biological oxygen demand (BOD{sub 5}) were removed at 70.6% and 49.4%, respectively at an optimum dose of 1200 mg L{sup −1} at pH 5.0. The biodegradable ratio BOD{sub 5}/COD was improved from 0.18 to 0.31 during pretreatment step by agitation and PFS coagulation. Thereafter, the effluent was diluted with sewage at a different ratio before it was subjected to sequencing batch reactor (SBR) treatment. Up to 93.3% BOD{sub 5}, 95.5% COD and 98.1% NH{sub 3}-N removal were achieved by SBR operated under anoxic–aerobic–anoxic conditions. The filtration process was carried out using sand and carbon as a dual filter media as polishing process. The final effluent concentration of COD, BOD{sub 5}, suspended solid (SS), NH{sub 3}-N and total organic carbon (TOC) were 72.4 mg L{sup −1}, 22.8 mg L{sup −1}, 24.2 mg L{sup −1}, 18.4 mg L{sup −1} and 50.8 mg L{sup −1} respectively, which met the discharge standard. The results indicated that a combined process of agitation-coagulation-SBR and filtration effectively eliminated

Modelling soil dust aerosol in the Bodélé depression during the BoDEx campaign

Directory of Open Access Journals (Sweden)

I. Tegen

2006-01-01

Full Text Available We present regional model simulations of the dust emission events during the Bodélé Dust Experiment (BoDEx that was carried out in February and March 2005 in Chad. A box model version of the dust emission model is used to test different input parameters for the emission model, and to compare the dust emissions computed with observed wind speeds to those calculated with wind speeds from the regional model simulation. While field observations indicate that dust production occurs via self-abrasion of saltating diatomite flakes in the Bodélé, the emission model based on the assumption of dust production by saltation and using observed surface wind speeds as input parameters reproduces observed dust optical thicknesses well. Although the peak wind speeds in the regional model underestimate the highest wind speeds occurring on 10–12 March 2005, the spatio-temporal evolution of the dust cloud can be reasonably well reproduced by this model. Dust aerosol interacts with solar and thermal radiation in the regional model; it is responsible for a decrease in maximum daytime temperatures by about 5 K at the beginning the dust storm on 10 March 2005. This direct radiative effect of dust aerosol accounts for about half of the measured temperature decrease compared to conditions on 8 March. Results from a global dust model suggest that the dust from the Bodélé is an important contributor to dust crossing the African Savannah region towards the Gulf of Guinea and the equatorial Atlantic, where it can contribute up to 40% to the dust optical thickness.

Impact of urban and industrial effluents on the coastal marine environment in Oran, Algeria.

Science.gov (United States)

Tayeb, A; Chellali, M R; Hamou, A; Debbah, S

2015-09-15

In Algeria most of the urban waste water is dumped without treatment into the Sea. It is tremendously important to assess the consequences of organic matter rich sewage on marine ecosystem. In this study we investigated the effects of industrial and urban sewage on the dissolved oxygen (O2), chemical oxygen demand (COD), biochemical oxygen demands (BOD5), pH, salinity, electrical conductivity (EC), Metal element (Hg, Pb, Cu, Ni, Cr, Cd), petroleum hydrocarbons (HC), oil and grease (OG) in Bay of Oran, Algeria. A ten-year follow-up research showed that the concentrations of oil and grease released into the bionetwork are of higher ecological impact and this needs to be given the desired consideration. Information on bathing water quality revealed that the most beaches in Oran are under the national environmental standard limit. Copyright © 2015 Elsevier Ltd. All rights reserved.

Photocatalytic oxidation of a reactive azo dye and evaluation of the ...

African Journals Online (AJOL)

driniev

2004-07-03

Jul 3, 2004 ... biological oxygen demand (BOD) test. The results ... Toxicity testing of photo- catalytically ... The dye solution contained in a flask was placed on a magnetic ..... opacity of the suspension in the excess of TiO2 particles (Fig. 4).

Pharmaceutical wastewater treatment: a physicochemical study

International Nuclear Information System (INIS)

Saleem, M.

2007-01-01

A physicochemical study for the treatment of pharmaceutical wastewater was performed. Objective of the laboratory investigation was to study the removal of color, Total Dissolved Solids (TDS), Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), turbidity and phenol and bring them up to the allowable limits for reuse purposes. Efficiency of coagulation, flocculation, sedimentation, sand filtration followed by activated carbon adsorption was determined. It was found that tested coagulants (alum, ferric chloride, and ferrous sulphate) are not much effective and required high dosage for the removal; of TSS, BOD, COD and turbidity. Alum was found to be more effective among tested coagulants and reduce TSS, BOD, COD and turbidity 79.6%, 34.8, 48.6% and 69.2% respectively. Sand filtration further reduced the studied parameters 97.7%, 95.7%, 93.9% and 76.9% respectively. As the concentration of phenol in the studied pharmaceutical wastewater was 100 mg/l, granular activated carbon was used to remove phenol up to the allowable limit for reuse purpose. Activated carbon adsorption further reduces phenol, TDS, TSS, BOD, and COD up to 99.9%, 99.1%, 21.4%, 81.3% and 71.1% respectively. High removal of color observed after activated carbon adsorption. It was concluded that the suggested treatment scheme is suitable to bring the effluent quality up to the water quality standards. (author)

Solid and suspended/dissolved waste (N, P, O) from rainbow trout (Oncorynchus mykiss)

DEFF Research Database (Denmark)

Dalsgaard, Anne Johanne Tang; Pedersen, Per Bovbjerg

2011-01-01

differences between the dietary treatment groups in the waste produced. On average, 48% of the ingestedNwas recovered in thewater (TANconstituting 64–79%of this)and7% inthesolids. In comparison, 1% of the ingested P was recovered in the water and 43% in the solids. A breakpoint value of 5.6 g standardized......Quantifying aquaculture waste into different waste fractions will make it possible to design different treatment setups for obtaining specific cleaning objectives. The aim of this study was therefore to measure “all” solid and suspended/dissolved (i.e. unsedimented) waste from juvenile rainbow...... trout (Oncorynchus mykiss) fed three commonly applied commercial diets, “all” waste referring to: total nitrogen (N), total ammonia nitrogen (TAN=NH3-N+NH4-N), total phosphorus (P), and organicmatter characterized by the chemical oxygen demand (COD) and the biological oxygen demand after 5 days (BOD5...

KEMAMPUAN SISTEM SARINGAN PASIR-TANAMAN MENURUNKAN NILAI BOD DAN COD AIR TERCEMAR LIMBAH PENCELUPAN

Directory of Open Access Journals (Sweden)

I W. Budiarsa Suyasa

2012-11-01

Full Text Available Colored of clothes has developed as concentrated in Denpasar area. The process has a negativeeffect because of waste, the resulting organic toxicants and heavy metal into aquatic system. The effect ofthe pollution including the river, well water and organism that live there. The research of bioremedialeffectiveness of herb-sand treatment system on laboratory simulation were studied in Denpasar, from June2004 to September 2004.For laboratory simulation, the plants were cultured in 25 cm sand bed, in between 5 cm palmfiber ofwhich were in between 10 cm pumicestone for the top and 5 cm gravel for the bottom with surface area of 25x 50 cm2.The result of treatment system showed that effective for decrease biological oxygen demandcompared to those of chemical oxygen demand parameters. The treatment system reduced significantly BODlevel respectively to 13,15 for 3 days, 11,19 for 10 days and 5,79 for 20 days with 85,55 – 93,63 effectively.While COD level respectively to 76,68 for 3 days, 61,38 for 10 days and 58,57 for 20 days with 42,78 – 56,50effectively. Time of treatment for 3, 10 and 20 days showed a little increase of pH from 6,87 to 7,00.

Advanced landfill leachate treatment using iron-carbon microelectrolysis- Fenton process: Process optimization and column experiments

International Nuclear Information System (INIS)

Wang, Liqun; Yang, Qi; Wang, Dongbo; Li, Xiaoming; Zeng, Guangming; Li, Zhijun; Deng, Yongchao; Liu, Jun; Yi, Kaixin

2016-01-01

Highlights: • Fe-C microelectrolysis-Fenton process is proposed to pretreat landfill leachate. • Operating variables are optimized by response surface methodology (RSM). • 3D-EEMs and MW distribution explain the mechanism of enhanced biodegradability. • Fixed-bed column experiments are performed at different flow rates. - Abstract: A novel hydrogen peroxide-enhanced iron-carbon (Fe-C) microelectrolysis reactor was proposed for the pretreatment of mature landfill leachate. This reactor, combining microelectrolysis with Fenton process, revealed high treatment efficiency. The operating variables, including Fe-C dosage, H_2O_2 concentration and initial pH, were optimized by the response surface methodology (RSM), regarding the chemical oxygen demand (COD) removal efficiency and biochemical oxygen demand: chemical oxygen demand (BOD_5/COD) as the responses. The highest COD removal (74.59%) and BOD_5/COD (0.50) was obtained at optimal conditions of Fe-C dosage 55.72 g/L, H_2O_2 concentration 12.32 mL/L and initial pH 3.12. Three-dimensional excitation and emission matrix (3D-EEM) fluorescence spectroscopy and molecular weight (MW) distribution demonstrated that high molecular weight fractions such as refractory fulvic-like substances in leachate were effectively destroyed during the combined processes, which should be attributed to the combination oxidative effect of microelectrolysis and Fenton. The fixed-bed column experiments were performed and the breakthrough curves at different flow rates were evaluated to determine the practical applicability of the combined process. All these results show that the hydrogen peroxide-enhanced iron-carbon (Fe-C) microelectrolysis reactor is a promising and efficient technology for the treatment of mature landfill leachate.

Advanced landfill leachate treatment using iron-carbon microelectrolysis- Fenton process: Process optimization and column experiments

Energy Technology Data Exchange (ETDEWEB)

Wang, Liqun, E-mail: 691127317@qq.com [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082 (China); Yang, Qi, E-mail: yangqi@hnu.edu.cn [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082 (China); Wang, Dongbo [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082 (China); Li, Xiaoming, E-mail: xmli121x@hotmail.com [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082 (China); Zeng, Guangming; Li, Zhijun; Deng, Yongchao; Liu, Jun; Yi, Kaixin [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082 (China)

2016-11-15

Highlights: • Fe-C microelectrolysis-Fenton process is proposed to pretreat landfill leachate. • Operating variables are optimized by response surface methodology (RSM). • 3D-EEMs and MW distribution explain the mechanism of enhanced biodegradability. • Fixed-bed column experiments are performed at different flow rates. - Abstract: A novel hydrogen peroxide-enhanced iron-carbon (Fe-C) microelectrolysis reactor was proposed for the pretreatment of mature landfill leachate. This reactor, combining microelectrolysis with Fenton process, revealed high treatment efficiency. The operating variables, including Fe-C dosage, H{sub 2}O{sub 2} concentration and initial pH, were optimized by the response surface methodology (RSM), regarding the chemical oxygen demand (COD) removal efficiency and biochemical oxygen demand: chemical oxygen demand (BOD{sub 5}/COD) as the responses. The highest COD removal (74.59%) and BOD{sub 5}/COD (0.50) was obtained at optimal conditions of Fe-C dosage 55.72 g/L, H{sub 2}O{sub 2} concentration 12.32 mL/L and initial pH 3.12. Three-dimensional excitation and emission matrix (3D-EEM) fluorescence spectroscopy and molecular weight (MW) distribution demonstrated that high molecular weight fractions such as refractory fulvic-like substances in leachate were effectively destroyed during the combined processes, which should be attributed to the combination oxidative effect of microelectrolysis and Fenton. The fixed-bed column experiments were performed and the breakthrough curves at different flow rates were evaluated to determine the practical applicability of the combined process. All these results show that the hydrogen peroxide-enhanced iron-carbon (Fe-C) microelectrolysis reactor is a promising and efficient technology for the treatment of mature landfill leachate.

Oxygenates to hike gasoline price

International Nuclear Information System (INIS)

Anon.

1992-01-01

This paper reports that cost of achieving required US gasoline formulations this winter in Environmental Protection Agency carbon monoxide (CO) nonattainment areas could reach 3-5 cents/gal, an Energy Information Administration analysis has found. EIA says new winter demand for gasoline blending oxygenates such as methyl tertiary butyl ether (MTBE) or ethanol created by 190 amendments to the Clean Air Act (CAA) will exceed US oxygenate production by 140,000-220,000 b/d. The shortfall must be made up from inventory or imports. EIA estimates the cost of providing incremental oxygenate to meet expected gasoline blending demand likely will result in a price premium of about 20 cents/gal of MTBE equivalent over traditional gasoline blend octane value. That cost likely will be added to the price of oxygenated gasoline

EFFECT OF OZONATED WATER ON THE ASSIMILABLE ORGANIC CARBON AND COLIFORM GROWTH RESPONSE VALUES AND ON PATHOGENIC BACTERIA SURVIVAL

Science.gov (United States)

The assimilable organic carbon (AOC) and coliform growth response (CGR) are bioassays used to determine water quality. AOC and CGR are better indexes in determining whether water can support the growth of bacteria than biological oxygen demand (BOD). The AOC value of reconditione...

Treatment of municipal wastewater in full-scale on-site sand filter reduces BOD efficiently but does not reach requirements for nitrogen and phosphorus removal.

Science.gov (United States)

Laaksonen, Petteri; Sinkkonen, Aki; Zaitsev, Gennadi; Mäkinen, Esa; Grönroos, Timo; Romantschuk, Martin

2017-04-01

A traditional sand filter for treatment of household wastewater was constructed in the fall of 2012 at Biolinja 12, Turku, Finland. Construction work was led and monitored by an authorized wastewater treatment consultant. The filter was placed on a field bordered by open ditches from all sides in order to collect excess rain and snowmelt waters. The filter was constructed and insulated from the environment so that all outflowing water was accounted for. Untreated, mainly municipal, wastewater from Varissuo suburb was pumped from a sewer separately via three septic tanks (volume = 1 m 3 each) into the filters. Normally, wastewater was distributed to ground filters automatically according to pre-programmed schedule. Initially, the daily flow was 1200 L day -1 to reflect the average organic load of a household of five persons (load: ca 237 g day -1 BOD; 73 g day -1 total N; and 10.4 g day -1 total P). Later in the test, the flow rate was decreased first to 900 and then to 600 L day -1 to better reflect the average volume produced by five persons. Volumes of inlet wastewater as well as treated water were monitored by magnetic flow meters. Samples were withdrawn from the inlet water, from the water entering the filters after the third septic tank, and from the outflowing water. After an initial adaption time, the reductions in BOD and chemical oxygen demand were constantly between 92 and 98%, showing that the biological degradation process in the filters functioned optimally and clearly comply with the national and EU standards. The reduction in total nitrogen and total phosphorus, however, reached required levels only during the first months of testing, apparently when buildup of microbial biomass was still ongoing. After this initial period of 3 months showing satisfactory reduction levels, the reduction of total nitrogen varied between 5 and 25% and total phosphorus mostly between 50 and 65%. Nitrification was efficient in the filter, but as indicated

Perbedaan Efektivitas Zeolit Dan Manganese Greensand Untuk Menurunkan Kadar Fosfat Dan Chemical Oxygen Demand Limbah Cair “Laundry Zone” Di Tembalang

OpenAIRE

Lavina, Dahona Lenthe; Sulistyani, Sulistyani; Rahadjo, Mursid

2016-01-01

Laundry business is a business in clothes washing services. Preliminary test results show that the levels of phosphate and COD laundry liquid wastes is 12,36 mg/l and 5.920 mg/l. These levels exceeded the water quality standard of waste that phosphate concentration of 2 mg/l and COD concentration of 100 mg/l. This research aimed to determine the difference effectiveness of zeolite and manganese greensand to decrease phosphate and chemical oxygen demand on waste "laundry zone" in Tembalang. T...

Water Quality Characteristics of Sembrong Dam Reservoir, Johor, Malaysia

Science.gov (United States)

Mohd-Asharuddin, S.; Zayadi, N.; Rasit, W.; Othman, N.

2016-07-01

A study of water quality and heavy metal content in Sembrong Dam water was conducted from April - August 2015. A total of 12 water quality parameters and 6 heavy metals were measured and classified based on the Interim National Water Quality Standard of Malaysia (INWQS). The measured and analyzed parameter variables were divided into three main categories which include physical, chemical and heavy metal contents. Physical and chemical parameter variables were temperature, dissolved oxygen (DO), biochemical oxygen demand (BOD), chemical oxygen demand (COD), total suspended solid (TSS), turbidity, pH, nitrate, phosphate, ammonium, conductivity and salinity. The heavy metals measured were copper (Cu), lead (Pb), aluminium (Al), chromium (Cr), ferum (Fe) and zinc (Zn). According to INWQS, the water salinity, conductivity, BOD, TSS and nitrate level fall under Class I, while the Ph, DO and turbidity lie under Class IIA. Furthermore, values of COD and ammonium were classified under Class III. The result also indicates that the Sembrong Dam water are not polluted with heavy metals since all heavy metal readings recorded were falls far below Class I.

Preliminary Study of Greywater Treatment through Rotating Biological Contactor

Directory of Open Access Journals (Sweden)

Ashfaq Ahmed Pathan

2011-07-01

Full Text Available The characteristics of the greywater vary from country to country and it depends upon the cultural and social behavior of the respective country. There was a considerable need to characterize and recycle the greywater. In this regard greywater was separated from the black water and analyzed for various physiochemical parameters. Among various greywater recycling treatment technologies, RBC (Rotating Biological Contactor is more effective treatment technique in reducing COD (Chemical Oxygen Demand and organic matters from the greywater. But this technology was not applied and tested in Pakistan. There was extensive need to investigate the RBC technology for greywater recycling at small scale before applying at mass scale. To treat the greywater, a single-stage RBC simulator was designed and developed at laboratory scale. An electric motor equipped with gear box to control the rotations of the disks was mounted on the tank. The simulator was run at the rate of 1.7 rpm. The disc area of the RBC was immersed about 40% in the greywater. Water samples were collected at each HRT (Hydraulic Retention Time and analyzed for the parameters such as pH, conductivity, TDS (Total Dissolved Solids, salinity, BOD5 (Biochemical Oxygen Demand, COD and suspended solids by using standard methods. The results are encouraging with percentage removal of BOD5 and COD being 53 and 60% respectively.

Batch leachate treatment using stirred electrocoagulation reactor with variation of residence time and stirring rate

Science.gov (United States)

Sitorus, I. S.; Astono, W.; Iswanto, B.

2018-01-01

This study aims to reduce pollutant levels of the leachate by electrocoagulation method using a stirred electrocoagulation reactor as the electrochemical water treatment. The release of active coagulants as metallic ions took place in the anode, while in the cathode, the electrolysis reaction in the form of hydrogen gas dischargeoccurred. The source of wastewater is Waste Water Treatment Plant inlet III of Bantar Gebang, Bekasi. Some parameters were analyzed in this research, i.e., Chemical Oxygen Demand (COD), Biochemical Oxygen Demand (BOD), NH3, NO3 -, NO2 -, N-total, and organic substances as well as the microorganism growth before and after electrocoagulation, with variations of detention time (seconds) of 10, 20, 120, 600 and rapid mixing conditions (rpm) of 60, 100 and 200. The results show that the greater the rapid mixing speed and the detention time of electrolysis, the higher the removal of contaminants in liquid waste. The optimum condition of electrocoagulation was encountered at 200 rpm rapid mixing with 600 seconds of processing time. The removal efficiencies of electrocoagulation method for each parameter are TSS of 46.80%, BOD5 of 71.33%, COD of 73.77%, Pb of 62.5%,and NH3-N of 57.92%,whereas the pH value has been increased from 8.03 to 8.95. The electrocoagulation method can reduce levels of pollutants, complying with the environmental standards.

Instruments for integrated water resources management : water quality modeling for sustainable wastewater management

NARCIS (Netherlands)

Barjoveanu, George; Teodosiu, Carmen; Cojocariu, Claudia; Augustijn, Dionysius C.M.; Craciun, Ioan

2013-01-01

This study presents the development and use of a hydraulic-coupled water quality model for the simulation of Biochemical Oxygen Demand (BOD) concentrations in the Bahlui River, a small river located in northeastern Romania. This river experiences the typical pollution problems for many Romanian

THE USE OF SILICA SAND, ZEOLITE AND ACTIVE CHARCOAL TO REDUCE BOD, COD AND TSS OF LAUNDRY WASTE WATER AS A BIOLOGY LEARNING RESOURCES

Directory of Open Access Journals (Sweden)

Moch Assiddieq

2017-11-01

Full Text Available The aquatic environment contaminated with detergent waste in high concentrations can endanger the lives human and biota in the water. This study aimed to determine the decrease of BOD, COD and TSS content of laundry liquid waste by using filter media of silica sand, zeolite, and activated charcoal. Filter medium 1a can reduce BOD level from 98.6 mg/L to 58.80 mg/L (40.36%, while medium 1b can decrease BOD level to 21.20 mg/L (78.48%. It showed that media 1a had not fulfilled the quality standard of BOD of waste water that is 50 mg/L, while media 1b had fulfilled the standard of quality. Filter media 1a can decrease COD level from 210 mg/L to 78.80 mg/L (62.47%, whereas medium 1b can decrease COD to 25.60 mg/L (87.80%. This showed that media 1a and media 1b had met the quality standard of COD of waste water that is 100 mg/L. Filter media 1a can decrease TSS level from 465 mg/L to 122.5 mg/L (73.65%, whereas medium 1b can decrease TSS level to 52.3 mg/L (88.75%. This showed that media 1a and media 1b had met the quality standard of TSS of waste water that is 150 mg/L.

Enraizamento de estacas lenhosas de pereira tratadas com AIB e mantidas em ambiente de estufa tipo B.O.D. e de telado Rooting of hardwood cuttings of pear tree with IBA under B.O.D. chamber and greenhouse environment

Directory of Open Access Journals (Sweden)

Wilson Barbosa

2007-01-01

Full Text Available Pesquisou-se o enraizamento da pereira em ambiente controlado de estufa tipo B.O.D. e em telado simples. Utilizou-se a cultivar híbrida 'Limeira', destinada exclusivamente para fins culinários e para porta-enxerto. Estacas lenhosas sem folhas, medindo 25 cm de comprimento, foram tratadas com ácido indolbutírico (AIB nas concentrações de 0; 2.000; 4.000 e 6.000 mg.L-1 por 10 segundos. Como substrato, utilizou-se da mistura de vermiculita e areia grossa (2:1 v/v, sendo a mesma umedecida com meio contendo solução salina MS e sacarose 1%. As estacas permaneceram por 42 dias dentro de estufas tipo B.O.D. (temperatura de 25ºC, umidade relativa do ar de 90% e fotoperíodo de 8 horas e de telado com irrigação por microaspersão, sem controle ambiental. Em ambiente controlado de estufa, as estacas não-tratadas com AIB iniciaram intensa brotação das gemas e formação de calo após sete dias do plantio. Já em ambiente de telado, essas estacas demoraram 21 dias para o início de brotação das gemas, mostrando menor desenvolvimento de calo. Nas estacas tratadas com AIB, os calos surgiram nas regiões dos cortes após o terceiro dia de incubação na estufa B.O.D. As raízes desenvolveram-se a partir dos tecidos da base e dos calos, tornando-se mais nítidas a partir de 14 e 28 dias, respectivamente, para os ambientes de estufa e de telado. Após 42 dias, o melhor percentual de enraizamento (83% foi verificado no tratamento com AIB a 2.000 mg.L-1, em ambiente de estufa B.O.D. O emprego dessa estufa, com temperatura, luz e umidade relativa controladas, mostrou-se viável em relação ao telado, no processo de enraizamento das estacas lenhosas da pereira 'Limeira', podendo favorecer o sistema de propagação vegetativa da pereira e encurtar o período da formação de mudas.The rooting of cuttings pear under controlled environment of chamber (B.O.D. type and greenhouse was searched. Hardwood cuttings of 'Limeira' pear, without leaves, measuring

BIODEGRADATION OF SUGARCANE VINASSES BY THE WHITE-ROT FUNGI Pleurotus ostreatus IN A PACKED BED REACTOR

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W.A. Tapie

2016-08-01

Full Text Available Sugarcane vinasses are considered a complex effluent because of its organic load, low pH, high temperature, and by the presence of recalcitrant substances such as melanoidins and phenolic compounds. The aim of this work was to evaluate the potential of the fungus Pleurotus ostreatus to carry out the biodegradation of sugarcane vinasses in a fixed-bed bioreactor. The experiments evidence the potential of the fungus Pleurotus ostreatus to carry out the decolorization (83%, the removal of the Chemical Oxygen Demand (COD=87% and the Biochemical Oxygen Demand (BOD5=92%, the reduction of total suspended solids (83% and volatile suspended solids (72% of vinasses. The technical simplicity of the proposed alternative as well as process performance reveals the potential of the fungus Pleurotus ostreatus for the treatment of sugarcane mill effluents.

Influence of vegetation and gravel mesh on the tertiary treatment of wastewater from a cosmetics industry.

Science.gov (United States)

Vlyssides, Apostolos G; Mai, Sofia T H; Barampouti, Elli Maria P; Loukakis, Haralampos N

2009-07-01

To estimate the influence of gravel mesh (fine and coarse) and vegetation (Phragmites and Arundo) on the efficiency of a reed bed, a pilot plant was included after the wastewater treatment plant of a cosmetic industry treatment system according to a 22 factorial experimental design. The maximum biochemical oxygen demand (BOD5), chemical oxygen demand (COD) and total phosphorous (TP) reduction was observed in the reactor, where Phragmites and fine gravel were used. In the reactor with Phragmites and coarse gravel, the maximum total Kjeldahl nitrogen (TKN) and total suspended solids (TSS) reduction was observed. The maximum total solids reduction was measured in the reed bed, which was filled with Arundo and coarse gravel. Conclusively, the treatment of a cosmetic industry's wastewater by reed beds as a tertiary treatment method is quite effective.

Electron beam treatment of wastewater

International Nuclear Information System (INIS)

Arai, H.; Hosono, M.; Shimizu, K.; Sugiyama, M.

1991-01-01

Supernatant comes from dewaterization of sewage sludge, and contains biologically nondegradable organics so that it is hard to be treated by conventional activated sludge. By electron beam (EB) irradiation, any kinds of organics in water can be oxidized to biodegradable organic acids. We studied the treatment of supernatant by application of this effect. The direct irradiation of the original supernatant was found not to be so effective to decrease COD. In order to increase the irradiation effect, supernatant was pretreated biologically to decrease the biodegradable organics in it. The chemical oxygen demand (COD) and biochemical oxygen demand (BOD) were decreased from 800 and 910 mg/L to 78 and 5 mg/L by this pretreatment, respectively. This pretreated supernatant was irradiated by EB of 2 MeV using a batch type reactor. The COD was gradually decreased with dose. In contrast, BOD was increased markedly, indicating increase in biodegradability. The irradiated sample water was treated biologically again. After the final biological treatment, COD was decreased below 30 mg/L in the case of 10 - 12 kGy irradiation. Finally, the initial COD of 800 mg/L was decreased below 30 mg/L by the combination of EB irradiation and biological treatment. The cost of irradiation for this process was evaluated preliminarily. (author)

Dye Removal From Textile Waste Water Through The Adsorption By Pumice Used In Stone Washing

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Körlü Aysegül Ekmekçi

2015-09-01

Full Text Available Because the waste production is inevitable in almost all industries, the elimination of these wastes is a requirement in terms of environmental regulations and welfare of all the creatures in the future. In this study, the use of the waste pumice stones of a denim washing mill is intended to eliminate the pollutant by a waste material and obtain economic benefits by converting it to the adsorbent. The pollutants in the effluents obtained from three different localisations of waste water treatment system of the same factory were removed through the adsorption. The experimental studies were carried out in three different steps; characterisation of adsorbent before and after adsorption; adsorption isotherm studies and biological oxygen demand (BOD, chemical oxygen demand (COD measurements. Characterisation studies showed that the waste pumice has almost the same structural properties with unused one except the existence of some organic residues coming from washing process. The results of adsorption studies conducted at the adsorbent concentrations changing from 5 to 35 g/l revealed that the decolourisation was initial dye-concentration dependent. According to the BOD and COD measurements, the supernatants obtained at the end of adsorption could be assumed as somewhat polluted and this result indicates that the organic impurities other than indigo were also removed through the adsorption.

Aerobic co-treatment of landfill leachate and domestic wastewater - are slowly biodegradable organics removed or simply diluted?

Science.gov (United States)

Campos, R; Ferraz, F M; Vieira, E M; Povinelli, J

2014-01-01

This study investigated the co-treatment of landfill leachate/domestic wastewater in bench-scale activated sludge (AS) reactors to determine whether the slowly biodegradable organic matter (SBOM) was removed rather than diluted. The AS reactors were loaded with mixtures of raw leachate and leachate that was pretreated by air stripping. The tested volumetric ratios were 0%, 0.2%, 2% and 5%. For all of the tested conditions, the reactors performed better when pretreated leachate was used rather than raw leachate, and the best volumetric ratio was 2%. The following removals were obtained: 97% for the biochemical oxygen demand (BOD5,20), 79% for total suspended solids, 77% for dissolved organic carbon and 84% for soluble chemical oxygen demand. Most of the pretreated leachate SBOM (65%) was removed rather than diluted or adsorbed into the sludge, as confirmed by Fourier transform infrared (FTIR) spectroscopy analyses.

Modeling the performance of 'up-flow anaerobic sludge blanket' reactor based wastewater treatment plant using linear and nonlinear approaches-A case study

Energy Technology Data Exchange (ETDEWEB)

Singh, Kunwar P., E-mail: kpsingh_52@yahoo.com [Environmental Chemistry Division, Indian Institute of Toxicology Research (Council of Scientific and Industrial Research), Post Box No. 80, MG Marg, Lucknow-226 002, UP (India); Basant, Nikita [School of Graduate Studies-Multiscale Modeling, Computational Simulations and Characterization in Material and Life Sciences, University of Modena and Reggio E., Modena (Italy); Malik, Amrita; Jain, Gunja [Environmental Chemistry Division, Indian Institute of Toxicology Research (Council of Scientific and Industrial Research), Post Box No. 80, MG Marg, Lucknow-226 002, UP (India)

2010-01-18

The paper describes linear and nonlinear modeling of the wastewater data for the performance evaluation of an up-flow anaerobic sludge blanket (UASB) reactor based wastewater treatment plant (WWTP). Partial least squares regression (PLSR), multivariate polynomial regression (MPR) and artificial neural networks (ANNs) modeling methods were applied to predict the levels of biochemical oxygen demand (BOD) and chemical oxygen demand (COD) in the UASB reactor effluents using four input variables measured weekly in the influent wastewater during the peak (morning and evening) and non-peak (noon) hours over a period of 48 weeks. The performance of the models was assessed through the root mean squared error (RMSE), relative error of prediction in percentage (REP), the bias, the standard error of prediction (SEP), the coefficient of determination (R{sup 2}), the Nash-Sutcliffe coefficient of efficiency (E{sub f}), and the accuracy factor (A{sub f}), computed from the measured and model predicted values of the dependent variables (BOD, COD) in the WWTP effluents. Goodness of the model fit to the data was also evaluated through the relationship between the residuals and the model predicted values of BOD and COD. Although, the model predicted values of BOD and COD by all the three modeling approaches (PLSR, MPR, ANN) were in good agreement with their respective measured values in the WWTP effluents, the nonlinear models (MPR, ANNs) performed relatively better than the linear ones. These models can be used as a tool for the performance evaluation of the WWTPs.

Modeling the performance of 'up-flow anaerobic sludge blanket' reactor based wastewater treatment plant using linear and nonlinear approaches-A case study

International Nuclear Information System (INIS)

Singh, Kunwar P.; Basant, Nikita; Malik, Amrita; Jain, Gunja

2010-01-01

The paper describes linear and nonlinear modeling of the wastewater data for the performance evaluation of an up-flow anaerobic sludge blanket (UASB) reactor based wastewater treatment plant (WWTP). Partial least squares regression (PLSR), multivariate polynomial regression (MPR) and artificial neural networks (ANNs) modeling methods were applied to predict the levels of biochemical oxygen demand (BOD) and chemical oxygen demand (COD) in the UASB reactor effluents using four input variables measured weekly in the influent wastewater during the peak (morning and evening) and non-peak (noon) hours over a period of 48 weeks. The performance of the models was assessed through the root mean squared error (RMSE), relative error of prediction in percentage (REP), the bias, the standard error of prediction (SEP), the coefficient of determination (R 2 ), the Nash-Sutcliffe coefficient of efficiency (E f ), and the accuracy factor (A f ), computed from the measured and model predicted values of the dependent variables (BOD, COD) in the WWTP effluents. Goodness of the model fit to the data was also evaluated through the relationship between the residuals and the model predicted values of BOD and COD. Although, the model predicted values of BOD and COD by all the three modeling approaches (PLSR, MPR, ANN) were in good agreement with their respective measured values in the WWTP effluents, the nonlinear models (MPR, ANNs) performed relatively better than the linear ones. These models can be used as a tool for the performance evaluation of the WWTPs.

The structure optimization of gas-phase surface discharge and its application for dye degradation

Science.gov (United States)

Ying, CAO; Jie, LI; Nan, JIANG; Yan, WU; Kefeng, SHANG; Na, LU

2018-05-01

A gas-phase surface discharge (GSD) was employed to optimize the discharge reactor structure and investigate the dye degradation. A dye mixture of methylene blue, acid orange and methyl orange was used as a model pollutant. The results indicated that the reactor structure of the GSD system with the ratio of tube inner surface area and volume of 2.48, screw pitch between a high-voltage electrode of 9.7 mm, high-voltage electrode wire diameter of 0.8 mm, dielectric tube thickness of 2.0 mm and tube inner diameter of 16.13 mm presented a better ozone (O3) generation efficiency. Furthermore, a larger screw pitch and smaller wire diameter enhanced the O3 generation. After the dye mixture degradation by the optimized GSD system, 73.21% and 50.74% of the chemical oxygen demand (COD) and total organic carbon removal rate were achieved within 20 min, respectively, and the biochemical oxygen demand (BOD) and biodegradability (BOD/COD) improved.

Cold climate performance analysis of on-site domestic wastewater treatment systems.

Science.gov (United States)

Williamson, Eric

2010-06-01

Household on-site septic systems with secondary wastewater treatment in Anchorage, Alaska, were sampled and analyzed for performance parameters during the winter to spring months. System types included intermittent dosing sand filters (ISF), three types of recirculating trickling filters (RTF), and suspended-growth aeration tanks. Total nitrogen from the trickling filter and aeration tank effluent was fairly uniform, at approximately 30 mg/L. Total suspended solids (TSS) means were mostly less than 15 mg/L. The 5-day biochemical oxygen demand (BODs) showed considerable variability, with means ranging from 9.2 mg/ L for ISFs up to 39.5 mg/L for one type of RTF, even though this type has shown excellent results in several test programs. The data suggested that effluent temperature within the sample range had almost no effect on effluent concentrations of BOD5 or TSS and only a small effect on the removal of total nitrogen. Non-climatic factors were probably of equal importance to treatment results.

Longitudinal data analysis in support of functional stability concepts for leachate management at closed municipal landfills

International Nuclear Information System (INIS)

Gibbons, Robert D.; Morris, Jeremy W.F.; Prucha, Christopher P.; Caldwell, Michael D.; Staley, Bryan F.

2014-01-01

Highlights: • Longitudinal data analysis using a mixed-effects regression model. • Dataset consisted of a total of 1402 samples from 101 closed municipal landfills. • Target analytes and classes generally showed predictable degradation trends. • Validates historical studies focused on macro organic indicators such as BOD. • BOD can serve as “gateway” indicator for planning leachate management. - Abstract: Landfill functional stability provides a target that supports no environmental threat at the relevant point of exposure in the absence of active control systems. With respect to leachate management, this study investigates “gateway” indicators for functional stability in terms of the predictability of leachate characteristics, and thus potential threat to water quality posed by leachate emissions. Historical studies conducted on changes in municipal solid waste (MSW) leachate concentrations over time (longitudinal analysis) have concentrated on indicator compounds, primarily chemical oxygen demand (COD) and biochemical oxygen demand (BOD). However, validation of these studies using an expanded database and larger constituent sets has not been performed. This study evaluated leachate data using a mixed-effects regression model to determine the extent to which leachate constituent degradation can be predicted based on waste age or operational practices. The final dataset analyzed consisted of a total of 1402 samples from 101 MSW landfills. Results from the study indicated that all leachate constituents exhibit a decreasing trend with time in the post-closure period, with 16 of the 25 target analytes and aggregate classes exhibiting a statistically significant trend consistent with well-studied indicators such as BOD. Decreasing trends in BOD concentration after landfill closure can thus be considered representative of trends for many leachate constituents of concern

Longitudinal data analysis in support of functional stability concepts for leachate management at closed municipal landfills

Energy Technology Data Exchange (ETDEWEB)

Gibbons, Robert D., E-mail: rdg@uchicago.edu [Center for Health Statistics, University of Chicago, 5841 S. Maryland Avenue, Chicago, IL 60637 (United States); Morris, Jeremy W.F., E-mail: jmorris@geosyntec.com [Geosyntec Consultants, 10220 Old Columbia Road, Suite A, Columbia, MD 21046 (United States); Prucha, Christopher P., E-mail: cprucha@wm.com [Groundwater Protection Program, Waste Management, 1550 Balmer Road, Box 200, Model City, NY 14107 (United States); Caldwell, Michael D., E-mail: mcaldwell@wm.com [Groundwater Protection Program, Waste Management, 3623 Wilson Road, Humble, TX 77396 (United States); Staley, Bryan F., E-mail: BStaley@erefdn.org [Environmental Research and Education Foundation, 3301 Benson Drive, Suite 301, Raleigh, NC 27609 (United States)

2014-09-15

Highlights: • Longitudinal data analysis using a mixed-effects regression model. • Dataset consisted of a total of 1402 samples from 101 closed municipal landfills. • Target analytes and classes generally showed predictable degradation trends. • Validates historical studies focused on macro organic indicators such as BOD. • BOD can serve as “gateway” indicator for planning leachate management. - Abstract: Landfill functional stability provides a target that supports no environmental threat at the relevant point of exposure in the absence of active control systems. With respect to leachate management, this study investigates “gateway” indicators for functional stability in terms of the predictability of leachate characteristics, and thus potential threat to water quality posed by leachate emissions. Historical studies conducted on changes in municipal solid waste (MSW) leachate concentrations over time (longitudinal analysis) have concentrated on indicator compounds, primarily chemical oxygen demand (COD) and biochemical oxygen demand (BOD). However, validation of these studies using an expanded database and larger constituent sets has not been performed. This study evaluated leachate data using a mixed-effects regression model to determine the extent to which leachate constituent degradation can be predicted based on waste age or operational practices. The final dataset analyzed consisted of a total of 1402 samples from 101 MSW landfills. Results from the study indicated that all leachate constituents exhibit a decreasing trend with time in the post-closure period, with 16 of the 25 target analytes and aggregate classes exhibiting a statistically significant trend consistent with well-studied indicators such as BOD. Decreasing trends in BOD concentration after landfill closure can thus be considered representative of trends for many leachate constituents of concern.

Manual or automated measuring of antipsychotics' chemical oxygen demand.

Science.gov (United States)

Pereira, Sarah A P; Costa, Susana P F; Cunha, Edite; Passos, Marieta L C; Araújo, André R S T; Saraiva, M Lúcia M F S

2018-05-15

Antipsychotic (AP) drugs are becoming accumulated in terrestrial and aqueous resources due to their actual consumption. Thus, the search of methods for assessing the contamination load of these drugs is mandatory. The COD is a key parameter used for monitoring water quality upon the assessment of the effect of polluting agents on the oxygen level. Thus, the present work aims to assess the chemical oxygen demand (COD) levels of several typical and atypical antipsychotic drugs in order to obtain structure-activity relationships. It was implemented the titrimetric method with potassium dichromate as oxidant and a digestion step of 2h, followed by the measurement of remained unreduced dichromate by titration. After that, an automated sequential injection analysis (SIA) method was, also, used aiming to overcome some drawbacks of the titrimetric method. The results obtained showed a relationship between the chemical structures of antipsychotic drugs and their COD values, where the presence of aromatic rings and oxidable groups give higher COD values. It was obtained a good compliance between the results of the reference batch procedure and the SIA system, and the APs were clustered in two groups, with the values ratio between the methodologies, of 2 or 4, in the case of lower or higher COD values, respectively. The SIA methodology is capable of operating as a screening method, in any stage of a synthetic process, being also more environmentally friendly, and cost-effective. Besides, the studies presented open promising perspectives for the improvement of the effectiveness of pharmaceutical removal from the waste effluents, by assessing COD values. Copyright © 2018 Elsevier Inc. All rights reserved.

Anaerobic treatment of wastewater with high suspended solids from a bulk drug industry using fixed film reactor (AFFR).

Science.gov (United States)

Gangagni Rao, A; Venkata Naidu, G; Krishna Prasad, K; Chandrasekhar Rao, N; Venkata Mohan, S; Jetty, Annapurna; Sarma, P N

2005-01-01

Studies were carried out on the treatment of wastewater from a bulk drug industry using an anaerobic fixed film reactor (AFFR) designed and fabricated in the laboratory. The chemical oxygen demand (COD) and total dissolved solids (TDS) of the wastewater were found to be very high with low biochemical oxygen demand (BOD) to COD ratio and high total suspended solid (TSS) concentration. Acclimatization of seed consortia and startup of the reactor was carried out by directly using the wastewater, which resulted in reducing the period of startup to 30 days. The reactor was studied at different organic loading rates (OLR) and it was found that the optimum OLR was 10 kg COD/m(3)/day. The wastewater under investigation, which had a considerable quantity of SS, was treated anaerobically without any pretreatment. COD and BOD of the reactor outlet wastewater were monitored and at steady state and optimum OLR 60-70% of COD and 80-90% of BOD were removed. The reactor was subjected to organic shock loads at two different OLR and the reaction could withstand the shocks and performance could be restored to normalcy at that OLR. The results obtained indicated that AFFR could be used efficiently for the treatment of wastewater from a bulk drug industry having high COD, TDS and TSS.

Feasibility of vermicomposting dewatered sludge from paper mills using Perionyx excavatus

Directory of Open Access Journals (Sweden)

Puspanjali Sonowal

2013-06-01

Full Text Available India has a large network of pulp and paper mills of varying capacity. On an industrial scale the sludge from paper and pulp mills is disposed of either as landfill or incinerated. Both methods result in the loss of a valuable resource and have obvious environmental and economic disadvantages. The solid waste from pulp and paper mills is a source of organic matter and its proper disposal and management is the responsibility of the industry. As composting/vermicomposting could be used to transform this waste trials were carried out to determine the feasibility of converting dewatered sludge (DS into a value added end product using an earthworm, Perionyx excavatus. The vermicomposting of the waste resulted in an increase in its electrical conductivity (EC, ash content, total nitrogen (TN, total phosphorous (TP and available phosphorous (AP, respectively, and a decrease in total organic carbon (TOC, biochemical oxygen demand (BOD, chemical oxygen demand (COD, oxygen uptake rate (OUR and evolution of carbon dioxide (CO2. Overall, the best treatment was T5 in which there was a 76.1% increase in TP, 58.7% in TN, 74.5% decrease in TOC , and a reduction of 6.7 fold in the production of CO2 and 10.7 fold in BOD, respectively. Our trials demonstrate that vermicomposting using an epigeic earthworm, Perionyx excavatus, is an alternate and environmentally safe way of recycling paper mill sludge if it is mixed with an appropriate amount of cow dung and food processing waste. Overall T5 was the best combination of paper mill sludge and waste for vermicomposting followed by T3, T2, T4 and T1, respectively.

Biogas Production and Removal COD – BOD and TSS from Wastewater Industrial Alcohol (Vinasse by Modified UASB Bioreactor

Directory of Open Access Journals (Sweden)

Utami Isni

2016-01-01

Full Text Available Biogas production and decreased organic loading of vinasse using a modified UASB bioreactor has been done successfully. Vinasse is waste from the ethanol industry which contains COD: 9.360 mg / L , BOD : 4.013 mg/L, and TSS: 317.5 mg/L. The purpose of this research was to study the performance of bioreactors Upflow Anaerobic Sludge Blanket (UASB to decompose the vinasse into biogas or methane. UASB operating principle is to distribute wastewater in the bioreactor to flow upward through the sludge blanket by setting the hidrolic retention time (HRT. Four UASB bioreactor columns were used in this experiment wherein each with a capacity of 50 L in volume; 23 cm inside diameter, and 120 cm. The variations of hydraulic capacity followed the variations of HRT in the range of 72-36 hours. Modifications were carried out on the top of column UASB with the aim of preventing gas losses and increasing the flowrate of gas out from the top of the column. The results showed that HRT increased from 36 h to 72 h followed by an increase in COD removal efficiency of 55.64% to 66.81%; BOD5 from 67.85% to 74.58%; and TSS from 66.69% to 84.19%. The maximum volume of biogas produced was in the range of 5.826 L / day (42.89% methane to 7.930 L / day (methane 58.06%.

water quality index estimate for isiodu river water during dredging in ...

African Journals Online (AJOL)

user

BOD5), dissolved oxygen (DO) ... quality index are fecal coliform count (6.96, 7.57mg/L), BOD5 (3.21, 3.17mg/L) DO (5.47, 5.36mg/L), pH (6.87, 6.86), temperature (13.20 ... Stations A and B are found upstream relative to the dredger position C,.

40 CFR 403.15 - Net/Gross calculation.

Science.gov (United States)

2010-07-01

... pollutants in the intake waters. (2) Credit for generic pollutants such as biochemical oxygen demand (BOD... to obtain credit for intake pollutants must make application to the Control Authority. Upon request... to reflect credit for pollutants in the intake water) if the requirements of paragraph (b) of this...

Evaluation of a treatment system wastewater prebeneficiado of coffee (Coffea arabica implemented in the community Carmen Pampa province of Nor Yungas of La Paz Department

Directory of Open Access Journals (Sweden)

Álvarez Javier

2011-08-01

Full Text Available This research was conducted in prebeneficiadora coffee plant of UAC-CP, located in the community of Carmen Pampa, Coroico Municipality, Nor Yungas of La Paz department. The objective was to determine the efficiency of wastewater treatment prebeneficiado coffee because it is not known to be effective in reducing the level of contamination of treated wastewater, and according to the results to correct and / or validate directly model system in place. For their study was established seven sampling points within the system of treatment and four replications were made at different times and with different amounts of coffee cherry. We evaluated the parameters of temperature, pH, settleable solids, total suspended solids, fixed and volatile, biochemical oxygen demand, chemical oxygen demand and dissolved oxygen. The temperature of wastewater entering the system has recorded 16.5 o C, increasing during the treatment process at 17.5 °C and record the output is 16.5 ºC. The pH increased from 4.51 to 6.04 which occurred at the last two gaps oxygenation and not in the neutralization tank. Settleable solids (SS increased from 0.1 mg / L to 0.15 mg / L, which was recorded at the lakes of oxygen, is attributed to the drag of fine gravel. Total suspended solids (TSS have been reduced from 1927.5 mg / L to 299 mg / L gradually throughout the treatment process. Fixed suspended solids (SSF were reduced from 137.5 mg / L to 58.5 mg / L. Volatile suspended solids (VSS were reduced from 1790 mg / L to 240.5 mg / L. Biochemical oxygen demand (BOD was reduced from 6102.5 mg O2 / L to 1245 mg O2 / L. The chemical oxygen demand (COD was reduced from 9800 mg O2 / L to 1658.75 mg O2 / L. Dissolved oxygen (DO increased from 0 to 2.4 mg O2 / L, in the last two gaps in oxygenation, due to the reduction of solids and chemical oxygen demand and biochemical oxygen. Of the nine parameters measured, six meet the maximum permissible values for download in source receptor (stream

The use of Moringa oleifera seed as a natural coagulant for wastewater treatment and heavy metals removal

Science.gov (United States)

Shan, Tan Chu; Matar, Manaf Al; Makky, Essam A.; Ali, Eman N.

2017-06-01

Moringa oleifera (MO) is a multipurpose tree with considerable potential and its cultivation is currently being actively promoted in many developing countries. Seeds of this tropical tree contain water-soluble, positively charged proteins that act as an effective coagulant for water and wastewater treatment. Based on this, water quality of "Sungai baluk" river was examined before and after the treatment using MO seed. MO seed exhibited high efficiency in the reduction and prevention of the bacterial growth in both wastewater and "Sungai baluk" river samples. The turbidity was removed up to 85-94% and dissolved oxygen (DO) was improved from 2.58 ± 0.01 to 4.00 ± 0.00 mg/L. The chemical oxygen demand (COD) and biological oxygen demand (BOD) were increased after the treatment from 99.5 ± 0.71 to 164.0 ± 2.83 mg/L for COD and from 48.00 ± 0.42 to 76.65 ± 2.33 mg/L for BOD, respectively. Nevertheless, there was no significant alteration of pH, conductivity, salinity and total dissolved solid after the treatment. Heavy metals such as Fe were fully eliminated, whereas Cu and Cd were successfully removed by up to 98%. The reduction of Pb was also achieved by up to 78.1%. Overall, 1% of MO seed cake was enough to remove heavy metals from the water samples. This preliminary laboratory result confirms the great potential of MO seed in wastewater treatment applications.

Final Environmental Impact Statement Permit Application by United States Steel Corp. Proposed Lake Front Steel Mill, Conneaut, Ohio. Volume 1,

Science.gov (United States)

1979-04-01

substrate (bottom) in an aquatic environment. Biochemical Oxygen Demand (BOD) - The amount of dissolved oxygen required to meet the metabolic needs of...Furnace & Ladle Lining Removal 6 Dempster Dinosaur Diesel Scrap Box Handling 1 Lift-A-Loft Propane Maintenance Scaffold 2 Breezewagon Furnace Cooling 1...10,000 lb Electric Miscellaneous (Battery) Roll Shop 2 Dempster Dinosaur 15 cu yd - Diesel Scale Handling 30 ton (incl. Plate Mill) 3 Motor Scooter 4

Fate of coliforms and pathogenic parasite in four full-scale sewage treatment systems in India.

Science.gov (United States)

Tyagi, Vinay Kumar; Sahoo, B K; Khursheed, Anwar; Kazmi, A A; Ahmad, Z; Chopra, A K

2011-10-01

The occurrence and removal of fecal indicators (total coliforms (TC), fecal coliforms (FC), fecal streptococci (FS)) and pathogens (helminthes eggs) were studied in various municipal wastewater treatment processes (UASB + FPU, ASP, EA, WSP). The reductions in TC and FC concentrations were usually between 2.0 and 2.5 log units in up-flow anaerobic sludge blanket reactor incorporated with final polishing unit (UASB + FPU). Almost similar reduction was observed in activated sludge process system (ASP) and waste stabilization ponds system (WSP), while it was log 3.0 in extended aeration system (EA). UASB + FPU and WSP systems were observed more efficient to reduce helminthes eggs at almost 100%, whereas only 97% removal was observed in case of ASP and EA system. In addition to monitoring of indicator organisms, turbidity, suspended solids (SS), and biochemical oxygen demand (BOD) were used as indirect measure of the potential presence of microorganisms. Interrelationship of BOD, SS, and turbidity with fecal indicator bacteria concentration in influent and effluent manifest that improvement of the microbiological quality of wastewater is strongly linked to the removal of BOD and SS.

Comparative studies on the differently operated trains of the North-Budapest Wastewater Treatment Plant.

Science.gov (United States)

Jobbágy, A; Palkó, Gy; Weinpel, T; Makó, M

2012-01-01

In order to reduce the pollution load of the Danube, the North-Budapest Wastewater Treatment Plant has been upgraded to enhanced nitrogen removal by establishing a new activated sludge treatment line and modifying the existing unit for nitrification and denitrification. As both the influent flow rate and the influent chemical oxygen demand (COD), biological oxygen demand (BOD(5)) and total suspended solids (TSS) concentration levels remained far below the design values, setting one fourth of the reactor volume out of operation in the Old Line, and operating the nitrification reactor of the New Line with part-time aeration proved to be possible. Analytical data as well as simulation studies supported the advantage of the intermittent-aeration process in efficient N-removal. However, the lengths of the aerated periods have to be increased with decreasing temperature, and thereby effluent total nitrogen (TN) concentration can increase due to decreasing denitrification efficiency. Potential occurrence of low-dissolved oxygen (DO) bulking should be hindered through applying an efficient anoxic selector system.

Dissolved oxygen - A target indicator in determining use of the Gulf of Kachchh waters

Digital Repository Service at National Institute of Oceanography (India)

Desa, E.; Zingde, M.D.; Vethamony, P.; Babu, M.T.; DeSousa, S.N.; Verlecar, X.N.

for the SW-1 waters. BOD -DO simulation shows that when effluents containing a BOD concentration of 50.0 mgl sup(-1) are introduced at three select locations, DO reduces from 5.1 mgl sup(-1) to 3.1,5.0 and 3.8 mgl sup(-1), respectively, indicating a strong...

The influence of ozonated time on the degree of depreciation of BOD, COD, TSS and phosphate in hospital liquid waste

International Nuclear Information System (INIS)

Isyuniarto and Andrianto

2009-01-01

The influence of ozonated time towards degree depreciation of Bode, COD, TSS and phosphate in hospital liquid waste was done. This research aim study influence of lime adding and ozone using to reduce of BOD, COD, TSS and phosphate in hospital waste. Added of lime mean for total increase ion OH - , while parameter of ozonization time mean to complete organic compounds oxidation in waste and flock formation. From this research it was found that optimum lime addition was 1.1% (% weight) and ozonization time was 20 minutes. In this condition it was achieved degree of BOD = 18.88 mg/l; COD = 25.68 mg/l, TSS = 80 mg/l and phosphate = 1.52 mg/l. This condition fulfil quality standard decided, that has to BOD = 75 mg/l; COD = 100 mg/l, TSS = 100 mg/l and phosphate = 2.0 mg/l. (author)

A combined electrocoagulation-sorption process applied to mixed industrial wastewater

Energy Technology Data Exchange (ETDEWEB)

Linares-Hernandez, Ivonne [Universidad Autonoma del Estado de Mexico, Facultad de Quimica, Paseo Colon interseccion Paseo Tollocan S/N, C.P. 50120, Toluca (Mexico); Barrera-Diaz, Carlos [Universidad Autonoma del Estado de Mexico, Facultad de Quimica, Paseo Colon interseccion Paseo Tollocan S/N, C.P. 50120, Toluca (Mexico)]. E-mail: cbarrera@uaemex.mx; Roa-Morales, Gabriela [Universidad Autonoma del Estado de Mexico, Facultad de Quimica, Paseo Colon interseccion Paseo Tollocan S/N, C.P. 50120, Toluca (Mexico); Bilyeu, Bryan [University of North Texas, Department of Materials Science and Engineering, PO Box 305310, Denton, TX 76203-5310 (United States); Urena-Nunez, Fernando [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, Col. Escandon, Delegacion Miguel Hidalgo, C.P. 11801, Mexico, D.F. (Mexico)

2007-06-01

The removal of organic pollutants from a highly complex industrial wastewater by a aluminium electrocoagulation process coupled with biosorption was evaluated. Under optimal conditions of pH 8 and 45.45 A m{sup -2} current density, the electrochemical method yields a very effective reduction of all organic pollutants, this reduction was enhanced when the biosorption treatment was applied as a polishing step. Treatment reduced chemical oxygen demand (COD) by 84%, biochemical oxygen demand (BOD{sub 5}) by 78%, color by 97%, turbidity by 98% and fecal coliforms by 99%. The chemical species formed in aqueous solution were determined. The initial and final pollutant levels in the wastewater were monitored using UV-vis spectrometry and cyclic voltammetry. Finally, the morphology and elemental composition of the biosorbent was characterized with scanning electron microscopy (SEM) and energy dispersion spectra (EDS)

Wastewater Treatment from Batik Industries Using TiO2 Nanoparticles

Science.gov (United States)

Arifan, Fahmi; Nugraheni, FS; Rama Devara, Hafiz; Lianandya, Niken Elsa

2018-02-01

Batik is cultural patterned fabric, and the this industries produce wastewater that can pollute the aquatic environment. Besides dyes, batik wastewater also contains synthetic compounds that are hard degraded, such as heavy metals, suspended solids, or organic compounds. In this study, photocatalitic membrane TiO2 coated plastic sheets have been used to degrade batik wastewater under solar exposure. A total of 8 pieces of catalyst sheets are added on 1000 ml of the waste, and managed to degrade 50.41% of the initial concentration during 5-days irradiation. In this study, several parameters of the water quality such as chemical oxygen demand (COD), biological oxygen demand (BOD), and total suspensed solids (TSS) of the wastewater were observed to be decreasing during photodegradation process. The catalyst sheet also is stable to be used repeatedly in wastewater treatment.

A combined electrocoagulation-sorption process applied to mixed industrial wastewater

International Nuclear Information System (INIS)

Linares-Hernandez, Ivonne; Barrera-Diaz, Carlos; Roa-Morales, Gabriela; Bilyeu, Bryan; Urena-Nunez, Fernando

2007-01-01

The removal of organic pollutants from a highly complex industrial wastewater by a aluminium electrocoagulation process coupled with biosorption was evaluated. Under optimal conditions of pH 8 and 45.45 A m -2 current density, the electrochemical method yields a very effective reduction of all organic pollutants, this reduction was enhanced when the biosorption treatment was applied as a polishing step. Treatment reduced chemical oxygen demand (COD) by 84%, biochemical oxygen demand (BOD 5 ) by 78%, color by 97%, turbidity by 98% and fecal coliforms by 99%. The chemical species formed in aqueous solution were determined. The initial and final pollutant levels in the wastewater were monitored using UV-vis spectrometry and cyclic voltammetry. Finally, the morphology and elemental composition of the biosorbent was characterized with scanning electron microscopy (SEM) and energy dispersion spectra (EDS)

Integrated Application of Multivariate Statistical Methods to Source Apportionment of Watercourses in the Liao River Basin, Northeast China

Directory of Open Access Journals (Sweden)

Jiabo Chen

2016-10-01

Full Text Available Source apportionment of river water pollution is critical in water resource management and aquatic conservation. Comprehensive application of various GIS-based multivariate statistical methods was performed to analyze datasets (2009–2011 on water quality in the Liao River system (China. Cluster analysis (CA classified the 12 months of the year into three groups (May–October, February–April and November–January and the 66 sampling sites into three groups (groups A, B and C based on similarities in water quality characteristics. Discriminant analysis (DA determined that temperature, dissolved oxygen (DO, pH, chemical oxygen demand (CODMn, 5-day biochemical oxygen demand (BOD5, NH4+–N, total phosphorus (TP and volatile phenols were significant variables affecting temporal variations, with 81.2% correct assignments. Principal component analysis (PCA and positive matrix factorization (PMF identified eight potential pollution factors for each part of the data structure, explaining more than 61% of the total variance. Oxygen-consuming organics from cropland and woodland runoff were the main latent pollution factor for group A. For group B, the main pollutants were oxygen-consuming organics, oil, nutrients and fecal matter. For group C, the evaluated pollutants primarily included oxygen-consuming organics, oil and toxic organics.

40 CFR 417.161 - Specialized definitions.

Science.gov (United States)

2010-07-01

... line to maintain minimal product quality. (f) The term BOD7 shall mean the biochemical oxygen demand as... apply to this subpart. (b) The term anhydrous product shall mean the theoretical product that would result if all water were removed from the actual product. (c) The term surfactant shall mean those...

River water quality assessment using environmentric techniques: case study of Jakara River Basin.

Science.gov (United States)

Mustapha, Adamu; Aris, Ahmad Zaharin; Juahir, Hafizan; Ramli, Mohammad Firuz; Kura, Nura Umar

2013-08-01

Jakara River Basin has been extensively studied to assess the overall water quality and to identify the major variables responsible for water quality variations in the basin. A total of 27 sampling points were selected in the riverine network of the Upper Jakara River Basin. Water samples were collected in triplicate and analyzed for physicochemical variables. Pearson product-moment correlation analysis was conducted to evaluate the relationship of water quality parameters and revealed a significant relationship between salinity, conductivity with dissolved solids (DS) and 5-day biochemical oxygen demand (BOD5), chemical oxygen demand (COD), and nitrogen in form of ammonia (NH4). Partial correlation analysis (r p) results showed that there is a strong relationship between salinity and turbidity (r p=0.930, p=0.001) and BOD5 and COD (r p=0.839, p=0.001) controlling for the linear effects of conductivity and NH4, respectively. Principal component analysis and or factor analysis was used to investigate the origin of each water quality parameter in the Jakara Basin and identified three major factors explaining 68.11 % of the total variance in water quality. The major variations are related to anthropogenic activities (irrigation agricultural, construction activities, clearing of land, and domestic waste disposal) and natural processes (erosion of river bank and runoff). Discriminant analysis (DA) was applied on the dataset to maximize the similarities between group relative to within-group variance of the parameters. DA provided better results with great discriminatory ability using eight variables (DO, BOD5, COD, SS, NH4, conductivity, salinity, and DS) as the most statistically significantly responsible for surface water quality variation in the area. The present study, however, makes several noteworthy contributions to the existing knowledge on the spatial variations of surface water quality and is believed to serve as a baseline data for further studies. Future

Using remotely sensed imagery to estimate potential annual pollutant loads in river basins.

Science.gov (United States)

He, Bin; Oki, Kazuo; Wang, Yi; Oki, Taikan

2009-01-01

Land cover changes around river basins have caused serious environmental degradation in global surface water areas, in which the direct monitoring and numerical modeling is inherently difficult. Prediction of pollutant loads is therefore crucial to river environmental management under the impact of climate change and intensified human activities. This research analyzed the relationship between land cover types estimated from NOAA Advanced Very High Resolution Radiometer (AVHRR) imagery and the potential annual pollutant loads of river basins in Japan. Then an empirical approach, which estimates annual pollutant loads directly from satellite imagery and hydrological data, was investigated. Six water quality indicators were examined, including total nitrogen (TN), total phosphorus (TP), suspended sediment (SS), Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), and Dissolved Oxygen (DO). The pollutant loads of TN, TP, SS, BOD, COD, and DO were then estimated for 30 river basins in Japan. Results show that the proposed simulation technique can be used to predict the pollutant loads of river basins in Japan. These results may be useful in establishing total maximum annual pollutant loads and developing best management strategies for surface water pollution at river basin scale.

Alteration of Water Pollution Level with the Seasonal Changes in Mean Daily Discharge in Three Main Rivers around Dhaka City, Bangladesh

Directory of Open Access Journals (Sweden)

Md. Saiful Islam

2015-06-01

Full Text Available A study based on the physicochemical parameters and dissolved metals levels from three main rivers around Dhaka City, Bangladesh, was conducted in order to determine the present pollution status and their alteration trends with the seasonal change of discharge amount. The water samples were collected from the rivers Buriganga, Turag, and Shitalakkhya during both dry and monsoon seasons. Physicochemical analyses revealed that most of the water quality parameters exceeded the recommended levels set by the Department of Environment (DoE, Bangladesh, during both the dry and monsoon seasons. A very strong positive correlation was found between biochemical oxygen demand (BOD and chemical oxygen demand (COD in all sampling points. Both BOD and COD values had a strong negative correlation with dissolved oxygen (DO in the Shitalakkhya River. Most of the dissolved metals concentrations in the water samples were similar. However, the concentrations of different physicochemical properties varied with the seasons. The dry season had significantly higher contamination loads, which were decreased during the monsoon season. Anthropogenic activities, as well as the variation in river water flow during different seasons were the main reasons for this high degree of water pollution.

Monitoring of impact of anthropogenic inputs on water quality of mangrove ecosystem of Uran, Navi Mumbai, west coast of India.

Science.gov (United States)

Pawar, Prabhakar R

2013-10-15

Surface water samples were collected from substations along Sheva creek and Dharamtar creek mangrove ecosystems of Uran (Raigad), Navi Mumbai, west coast of India. Water samples were collected fortnightly from April 2009 to March 2011 during spring low and high tides and were analyzed for pH, Temperature, Turbidity, Total solids (TS), Total dissolved solids (TDS), Total suspended solids (TSS), Dissolved oxygen (DO), Biochemical oxygen demand (BOD), Carbon dioxide (CO2), Chemical oxygen demand (COD), Salinity, Orthophosphate (O-PO4), Nitrite-nitrogen (NO2-N), Nitrate-nitrogen (NO3-N), and Silicates. Variables like pH, turbidity, TDS, salinity, DO, and BOD show seasonal variations. Higher content of O-PO4, NO3-N, and silicates is recorded due to discharge of domestic wastes and sewage, effluents from industries, oil tanking depots and also from maritime activities of Jawaharlal Nehru Port Trust (JNPT), hectic activities of Container Freight Stations (CFS), and other port wastes. This study reveals that water quality from mangrove ecosystems of Uran is deteriorating due to industrial pollution and that mangrove from Uran is facing the threat due to anthropogenic stress. Copyright © 2013 Elsevier Ltd. All rights reserved.

Performance evaluation of a full-scale ABS resin manufacturing wastewater treatment plant: a case study in Tabriz Petrochemical Complex

Directory of Open Access Journals (Sweden)

Mohammad Shakerkhatibi

2016-08-01

Full Text Available Background: The measurement data regarding the influent and effluent of wastewater treatment plant (WWTP provides a general overview, demonstrating an overall performance of WWTP. Nevertheless, these data do not provide the suitable operational information for the optimization of individual units involved in a WWTP. A full-scale evolution of WWTP was carried out in this study via a reconciled data. Methods: A full-scale evolution of acrylonitrile, butadiene and styrene (ABS resin manufacturing WWTP was carried out. Data reconciliation technique was employed to fulfil the mass conservation law and also enhance the accuracy of the flow measurements. Daily average values from long-term measurements by the WWTP library along with the results of four sampling runs, were utilized for data reconciliation with further performance evaluation and characterization of WWTP. Results: The full-scale evaluation, based on balanced data showed that removal efficiency based on chemical oxygen demand (COD and biochemical oxygen demand (BOD5 through the WWTP were 80% and 90%, respectively, from which only 28% of COD and 20% of BOD5 removal had occurred in biological reactor. In addition, the removal efficiency of styrene and acrylonitrile, throughout the plant, was approximately 90%. Estimation results employing Toxchem model showed that 43% of acrylonitrile and 85% of styrene were emitted into the atmosphere above water surfaces. Conclusion: It can be concluded that the volatilization of styrene and acrylonitrile is the main mechanism for their removal along with corresponded COD elimination from the WWTP.

Water Quality Degradation and Management Strategies for Swine and Rice Farming Wastewater in the Tha Chin River Basin

Directory of Open Access Journals (Sweden)

Abigail Henderson

2017-11-01

Full Text Available Water quality in the Tha Chin River regularly exceeds biological oxygen demand (BOD standards of Thailand’s Enhancement and Conservation of National Environmental Quality Act. This study quantified the BOD loading from rice cultivation and swine farming to the Tha Chin River using effluent data and procedures from the Pollution Control Department (PCD, geospatial land-use maps from the Land Development Department, and water quality data from the Ministry of Natural Resources and the Environment. It was determined that the BOD loading was 12 tons/day from swine farming in 2015 and 52 tons/day, on average, from rice farming between 2002 and 2011. Technology-specific, community-scale wastewater management strategies were recommended for both industries: feasibility studies revealed 66 potential sites for constructed wetland implementation and 7 subdistricts suitable for biogas network pipelines. It was determined that if these projects are implemented in conjunction, the BOD would be reduced by 6% (0.3 mg/L in the entire river or 11% (0.5 mg/L at the three water quality monitoring stations proximate to swine farms. These reductions would have a substantial effect on the water quality of the Tha Chin River, and governmental agencies such as the PCD should strongly consider subsidization and implementation of these projects.

Effect of Gamma Irradiation and Coagualtion on the Molegular Weight Distribution of Soluble Organic Substances in Paper Mill Effluent

International Nuclear Information System (INIS)

He Shijun; Wang Jianlong; Wan Jianxin; Sun Mengmeng; Ye Longfei

2012-01-01

In order to look into the insights of the influence of gamma irradiation and coagulation on the molecular weight distribution (MWD) of soluble organic substances in real paper mill effluent, various parameters of wastewater samples before and after treated were investigated, including chemical oxygen demand (COD), biochemical oxygen demand (BOD 5 ), dissolved organic carbon (DOC) and absorbance at 254 nm wavelength (UV 254 ) as well. In addition, the effects of irradiation on oxygen uptake and on acute toxicity were also presented. The results showed that irradiation alone cannot promote the biodegradability and oxygen uptake as originally expected. The whole acute toxicity of samples was reduced after gamma irradiation. On the other side, coagulation can not only effectively eliminate the sectors with high molecular weight (MW>3000 Dalton, in short HMW), but also improve the capacity of ionizing irradiation initiated the transformation of medium molecular weight (1000 Dalton< MW<3000 Dalton, in short MMW) into low molecular weight (MW<1000 Dalton, in short LWM), which is readily degraded by the subsequently activated sludge process. (author)

Effect of Gamma Irradiation and Coagualtion on the Molegular Weight Distribution of Soluble Organic Substances in Paper Mill Effluent

Energy Technology Data Exchange (ETDEWEB)

Shijun, He; Jianlong, Wang [Institute of Nuclear and New Energy Technology (INET), Tsinghua University, Beijing 100084 (China); Jianxin, Wan; Mengmeng, Sun [Institute of Nuclear and New Energy Technology (INET), Tsinghua University, Beijing 100084 (China); School of Resources and Environmental Engineering, Wuhan University of Technology, Wuhan 430070 (China); Longfei, Ye [Institute of Nuclear and New Energy Technology (INET), Tsinghua University, Beijing 100084 (China); College of Environmental Science and Engineering, Hunan University, Changsha, Hunan 410082 (China)

2012-07-01

In order to look into the insights of the influence of gamma irradiation and coagulation on the molecular weight distribution (MWD) of soluble organic substances in real paper mill effluent, various parameters of wastewater samples before and after treated were investigated, including chemical oxygen demand (COD), biochemical oxygen demand (BOD{sub 5}), dissolved organic carbon (DOC) and absorbance at 254 nm wavelength (UV{sub 254}) as well. In addition, the effects of irradiation on oxygen uptake and on acute toxicity were also presented. The results showed that irradiation alone cannot promote the biodegradability and oxygen uptake as originally expected. The whole acute toxicity of samples was reduced after gamma irradiation. On the other side, coagulation can not only effectively eliminate the sectors with high molecular weight (MW>3000 Dalton, in short HMW), but also improve the capacity of ionizing irradiation initiated the transformation of medium molecular weight (1000 Dalton

The viability of biological treatment at Ibi wastewater treatment station; Viabilidad del tratamiento biologico de aguas residuales

Energy Technology Data Exchange (ETDEWEB)

Flor Garcia, M.V.; Morenilla Martinez, J.J.; Ruiz Zapata, R.

1996-06-01

In this study, we have proved the viability of biological treatment of leaving waters from Ibi Wastewater Treatment Station, where water is subject to the action of coagulant agents, following a physical and chemical process. the experience was based on wastewater treatment by using activated sludge, at experimental scale in a pilot plant. During the experiments, we controlled the main parameters which indicate treatment success; namely, Suspended Solids (SS), pH, Biochemical Oxygen Demand (BOD) and Chemical Oxygen Demand (COD), in addition to other substances such as nutrients and toxicants, and inhibitors of bio metabolism. (Author) 6 refs.

Transport of North African dust from the Bodélé depression to the Amazon Basin: a case study

Directory of Open Access Journals (Sweden)

Y. Ben-Ami

2010-08-01

Full Text Available Through long-range transport of dust, the North-African desert supplies essential minerals to the Amazon rain forest. Since North African dust reaches South America mostly during the Northern Hemisphere winter, the dust sources active during winter are the main contributors to the forest. Given that the Bodélé depression area in southwestern Chad is the main winter dust source, a close link is expected between the Bodélé emission patterns and volumes and the mineral supply flux to the Amazon.

Until now, the particular link between the Bodélé and the Amazon forest was based on sparse satellite measurements and modeling studies. In this study, we combine a detailed analysis of space-borne and ground data with reanalysis model data and surface measurements taken in the central Amazon during the Amazonian Aerosol Characterization Experiment (AMAZE-08 in order to explore the validity and the nature of the proposed link between the Bodélé depression and the Amazon forest.

This case study follows the dust events of 11–16 and 18–27 February 2008, from the emission in the Bodélé over West Africa (most likely with contribution from other dust sources in the region the crossing of the Atlantic Ocean, to the observed effects above the Amazon canopy about 10 days after the emission. The dust was lifted by surface winds stronger than 14 m s⁻¹, usually starting early in the morning. The lofted dust, mixed with biomass burning aerosols over Nigeria, was transported over the Atlantic Ocean, and arrived over the South American continent. The top of the aerosol layer reached above 3 km, and the bottom merged with the boundary layer. The arrival of the dusty air parcel over the Amazon forest increased the average concentration of aerosol crustal elements by an order of magnitude.

Oxygen rocking aqueous batteries utilizing reversible topotactic oxygen insertion/extraction in iron-based perovskite oxides Ca1-xLaxFeO3-δ

Science.gov (United States)

Hibino, Mitsuhiro; Kimura, Takeshi; Suga, Yosuke; Kudo, Tetsuichi; Mizuno, Noritaka

2012-08-01

Developments of large-scale energy storages with not only low cost and high safety but also abundant metals are significantly demanded. While lithium ion batteries are the most successful method, they cannot satisfy all conditions. Here we show the principle of novel lithium-free secondary oxygen rocking aqueous batteries, in which oxygen shuttles between the cathode and anode composed of iron-based perovskite-related oxides Ca0.5La0.5FeOz (2.5 topotactic oxygen extraction and reinsertion during discharge and charge processes.

Treatment and Energy Valorisation of an Agro-Industrial Effluent in Upflow Anaerobic Sludge Reactor (UASB)

Science.gov (United States)

Martins, Ramiro; Boaventura, Rui; Paulista, Larissa

2017-12-01

The accelerated growth of the population brings with it an increase in the generation of agro-industrial effluents. The inadequate discharge of these effluents significantly affects the quality of water resources. In this way, it becomes important to invest in treatment processes for agro-industrial effluents, particularly low-cost ones. In this context, the present study includes the design and construction of an UASB reactor and optimization of the anaerobic digestion treatment of the raw effluent from sweet chestnut production in the agro-industrial company Sortegel. The efficiency of the system was evaluated through the determination / monitoring of oxygen chemical oxygen demand (COD), biochemical oxygen demand (BOD5), total suspended solids (TSS), biogas production rate and quality (% methane). The reactor was fed for 25 weeks and operated under mesophilic conditions (temperature 30-40 °C). Different values were tested for the hydraulic retention time (HRT) and volumetric flow rate (VF): 0.66 days (VF=1509 L.m-3.d-1); 1.33 days (VF=755 L.m-3.d-1); 2.41 d days (VF=415 L.m-3.d-1). The average COD removal efficiency reached values of 69%, 82% and 75%, respectively, and simultaneously the associated BOD5 removal efficiency was 84%, 91% and 70%. As regards TSS, removal values were 78%, 94% and 63%. In addition, high methane production rates were obtained, between 2500 and 4800 L CH4.kg-1 COD removed d-1. For all the hydraulic retention times tested, high concentrations of methane in the biogas were recorded: 66-75%, 70% and 75% for HRT of 0.66, 1.33 and 2.41 days, respectively.

Separating the effects of partial submergence and soil oxygen demand on plant physiology.

Science.gov (United States)

van Bodegom, Peter M; Sorrell, Brian K; Oosthoek, Annelies; Bakker, Chris; Aerts, Rien

2008-01-01

In wetlands, a distinct zonation of plant species composition occurs along moisture gradients, due to differential flooding tolerance of the species involved. However, "flooding" comprises two important, distinct stressors (soil oxygen demand [SOD] and partial submergence) that affect plant survival and growth. To investigate how these two flooding stressors affect plant performance, we executed a factorial experiment (water depth x SOD) for six plant species of nutrient-rich and nutrient-poor conditions, occurring along a moisture gradient in Dutch dune slacks. Physiological, growth, and biomass responses to changed oxygen availability were quantified for all species. The responses were consistent with field zonation, but the two stressors affected species differently. Increased SOD increased root oxygen deprivation, as indicated by either raised porosity or increased alcohol dehydrogenase (ADH) activity in roots of flood-intolerant species (Calamagrostis epigejos and Carex arenaria). While SOD affected root functioning, partial submergence tended more to reduce photosynthesis (as shown both by gas exchange and 13C assimilation), leaf dark respiration, 13C partitioning from shoots to roots, and growth of these species. These processes were especially affected if the root oxygen supply was depleted by a combination of flooding and increased SOD. In contrast, the most flood-tolerant species (Juncus subnodulosus and Typha latifolia) were unaffected by any treatment and maintained high internal oxygen concentrations at the shoot : root junction and low root ADH activity in all treatments. For these species, the internal oxygen transport capacity was well in excess of what was needed to maintain aerobic metabolism across all treatments, although there was some evidence for effects of SOD on their nitrogen partitioning (as indicated by 865N values) and photosynthesis. Two species intermediate in flooding tolerance (Carex nigra and Schoenus nigricans) responded more

Biodegradation and kinetics of organic compounds and heavy metals in an artificial wetland system (AWS) by using water hyacinths as a biological filter.

Science.gov (United States)

Rodríguez-Espinosa, P F; Mendoza-Pérez, J A; Tabla-Hernandez, J; Martínez-Tavera, E; Monroy-Mendieta, M M

2018-01-02

The objective of the present study was to investigate the ability of water hyacinth (Eichhornia crassipes) to absorb organic compounds (potassium hydrogen phthalate, sodium tartrate, malathion, 2,4-dichlorophenoxy acetic acid (2,4-D), and piroxicam). For the aforementioned purpose, an artificial wetland system (AWS) was constructed and filled with water hyacinth collected from the Valsequillo Reservoir, Puebla, Mexico. Potassium hydrogen phthalate and sodium tartrate were measured in terms of chemical oxygen demand (COD) and biological oxygen demand (BOD). The present study indicated that the water hyacinths absorbed nearly 1.8-16.6 g of COD kg -1 dm (dry mass of water hyacinth), while the absorbance efficiency of BOD was observed to be 45.8%. The results also indicated that the maximum absorbance efficiency of malathion, 2,4-D, and piroxicam was observed to be 67.6%, 58.3%, and 99.1%, respectively. The kinetics of organic compounds fitted different orders as malathion followed a zeroth-order reaction, while 2,4-D and piroxicam followed the first-order reactions. Preliminary assessment of absorption of heavy metals by the water hyacinth in the AWS was observed to be (all values in mg g -1 ) 7 (Ni), 13.4 (Cd), 16.3 (Pb), and 17.5 (Zn) of dry biomass, thus proving its feasibility to depurate wastewater.

Reduction of Wastewater Pollutants of Mandalay City Slaughterhouse

International Nuclear Information System (INIS)

May Thant Zin; Sint Soe

2010-12-01

Slaughterhouse (Meat Production Factor)under Mandaly City Development Committee (MCDC) in Myanmar has been discharging raw wastewater directly into Tat Thay Pont which is located at the back side of the slaughterhouse.It can cause some water pollutants in water source and need to prevent environmental impact. This paper was studied on the treatment of slaughterhouse wastewater using appropriate technique available in local area. Sample collection of slaughterhouse waste, analysing of waste quality on current situation,different ways of pre-treating and anaerobically digestion without recycling were done. Screening, coagulation, sedimentation and charcoal filtration were included as pre-treating steps before major anaerobic digestion. Ferric chloride and aluminum sulphate chemicals of both commercial and analytical grades were used as coagulants. Laboratory-scaled anaerobic reactor constructed with polyvinyl chloride (PVC) material was 15 cm diameter and 90 cm heigh. MCDC slaughterhouse wastewater containing 98.56% of total coarse particles was removed via minimum size of 1500 micron screen. Aluminium sulphate gave the best removal of fine solid particles. It was observed that pre-treating steps can reduce 56.72% of initial biological oxygen demand (BOD), 51.482% of initial chemical oxygen demand (COD) and 45.18% of inital total suspended solid (TSS) and anaerobic digester after 30 days can reduce 77.4% of influent BOD,81.5% of influent COD and 87.3% of influent TSS.

A yeast co-culture-based biosensor for determination of waste water contamination levels.

Science.gov (United States)

Yudina, N Yu; Arlyapov, V A; Chepurnova, M A; Alferov, S V; Reshetilov, A N

2015-10-01

Artificial microbial co-cultures were formed to develop the receptor element of a biosensor for assessment of biological oxygen demand (BOD). The co-cultures possessed broad substrate specificities and enabled assays of water and fermentation products within a broad BOD range (2.4-80 mg/dm(3)) with a high correlation to the standard method (R = 0.9988). The use of the co-cultures of the yeasts Pichia angusta, Arxula adeninivorans and Debaryomyces hansenii immobilized in N-vinylpyrrolidone-modified poly(vinyl alcohol) enabled developing a BOD biosensor possessing the characteristics not inferior to those in the known biosensors. The results are indicative of a potential of using these co-cultures as the receptor element base in prototype models of instruments for broad application. Copyright © 2015 Elsevier Inc. All rights reserved.

Disinfection of wastewater from a Riyadh Wastewater Treatment Plant with ionizing radiation

International Nuclear Information System (INIS)

Basfar, A.A.; Abdel Rehim, F.

2002-01-01

The goal of this research was to establish the applicability of the electron beam treatment process for treating wastewater intended for reuse. The objective of this study was to determine the effectiveness of gamma irradiation in the disinfection of wastewater, and the improvement of the water quality by determining the changes in organic matter as indicated by the measurement of biochemical oxygen demand (BOD), chemical oxygen demand (COD) and total organic carbon (TOC). Samples of effluent, before and after chlorination, and sludge were obtained from a Riyadh Wastewater Treatment Plant. The studies were conducted using a laboratory scale 60 Co gamma source. The improvement in quality of the irradiated samples was demonstrated by the reduction in bacteria, and the reduction in the BOD, COD and TOC. Radiation of the wastewater provided adequate disinfection while at the same time increasing the water quality. This treatment could lead to additional opportunities for the reuse of this valuable resource. Limited studies, conducted on the anaerobically digested secondary biosolids, showed an improvement in bacterial content and no change in COD

Removal of color and chemical oxygen demand using a coupled coagulation-electrocoagulation-ozone treatment of industrial wastewater that contains offset printing dyes

International Nuclear Information System (INIS)

Roa M, G.; Barrera D, C.; Balderas H, P.; Zaldumbide O, F.; Reyes P, H.; Bilyeu, B.

2014-01-01

Industrial offset printing processes generate wastewater with highly colored obtaining values of 5 x 10 6 Pt-Co units and great values of chemical oxygen demand (COD) 5.3 x 10 -5 mg L -1 . Thus, conventional technologies such as biologicals treatment fail in reaching the discharge limits. In this research, a sequential treatment was applied: coagulation with aluminum hydroxychloride (AHC), electrocoagulation with Al anodes and finally ozonation. Optimal conditions are found when adding 20 mg L -1 AHC, followed by electrocoagulation at 4 A for 50 min, and finally alkaline ozonation for 15 min, resulting in an overall color removal of 99.99% color and 99.35 COD. The sludge generated by the coagulation process was analyzed by scanning electron microscopy and energy dispersive X-ray (EDX) microanalysis. (Author)

Removal of color and chemical oxygen demand using a coupled coagulation-electrocoagulation-ozone treatment of industrial wastewater that contains offset printing dyes

Energy Technology Data Exchange (ETDEWEB)

Roa M, G.; Barrera D, C.; Balderas H, P.; Zaldumbide O, F. [Centro Conjunto de Investigacion en Quimica Sustentable UAEM-UNAM, Km 14.5 Carretera Toluca-Atlacomulco, 50200 San Cayetano-Toluca, Estado de Mexico (Mexico); Reyes P, H. [Universidad Autonoma del Estado de Mexico, Facultad de Quimica, Paseo Colon y Paseo Tollocan s/n, 50120 Toluca, Estado de Mexico (Mexico); Bilyeu, B., E-mail: groam@uaemex.mx [Xavier University of Louisiana, Department of Chemistry, 1 Drexel Drive, New Orleans, LA 70125 (United States)

2014-07-01

Industrial offset printing processes generate wastewater with highly colored obtaining values of 5 x 10{sup 6}Pt-Co units and great values of chemical oxygen demand (COD) 5.3 x 10{sup -5} mg L{sup -1}. Thus, conventional technologies such as biologicals treatment fail in reaching the discharge limits. In this research, a sequential treatment was applied: coagulation with aluminum hydroxychloride (AHC), electrocoagulation with Al anodes and finally ozonation. Optimal conditions are found when adding 20 mg L{sup -1} AHC, followed by electrocoagulation at 4 A for 50 min, and finally alkaline ozonation for 15 min, resulting in an overall color removal of 99.99% color and 99.35 COD. The sludge generated by the coagulation process was analyzed by scanning electron microscopy and energy dispersive X-ray (EDX) microanalysis. (Author)

Utilization of Paper Sludge Wastes for Treatment of Wastewater from Food Processing Industries

Directory of Open Access Journals (Sweden)

Tohru Suzuki

2012-12-01

Full Text Available The food processing industries usually produced large amount of wastewater containing fine and small particles. It takes long time for complete settlement of the fine and small particles in the wastewater. The coagulation method appears to become one of the useful treatments. New inorganic coagulant named “Agoclean‒P” has been developed from paper sludge ash. The treatment by coagulation and flocculation were carried out for the wastewater from three different food processing industries namely soup, tofu, and natto. “Hi‒Biah‒System”, which is an in‒situ solidification system, was used for the continuous treatment of wastewater. The parameters for the water quality were pH, five‒day biochemical oxygen demand (BOD5, chemical oxygen demand (COD, total suspended solids (TSS, total nitrogen (TN and total phosphorus (TP. These parameters after the treatment became much lower values relative to those obtained before the treatment.

Treatment of real paracetamol wastewater by fenton process

Directory of Open Access Journals (Sweden)

Dalgic Gamze

2017-01-01

Full Text Available The study investigated the pretreatment of real paracetamol (PCT wastewater of a pharmaceutical industry by Fenton process. At the best experimental conditions (COD/H2O2 = 1/1, Fe+2/H2O2 = 1/70, settling method:centrifuging, pH 6 at settling step, 92.7, 92.7, 95.5, 99.1, 99.9 and 99.4% of chemical oxygen demand (COD, total organic carbon (TOC, 5-day biological oxygen demand (BOD5, PCT, para-amino phenol (PAP and aniline were removed, respectively. Changes in the concentrations of these parameters were also investigated for both oxidation and settling steps of Fenton process. It was found that COD and TOC were removed at the settling step (precipitation whereas PCT, PAP and aniline were removed at the oxidation step. Mass balance calculations were also studied to show the mass distributions of COD in different phases (gas + foam, effluent and sludge. Fenton process was found as an effective method for the pretreatment of real PCT wastewater for discharging in a determined collective treatment plant.

Adaptation of streeter model - Phelps for water quality modeling in a large semi-arid basin.

OpenAIRE

Wagner Josà da Silva Mendes

2014-01-01

This paper presents an adaptation of the classical model of Streeter-Phelps modeling of Dissolved Oxygen (DO) and Biochemical Oxygen Demand (BOD) in the basin of the Upper Jaguaribe (25,000 km2), State of Ceara, Brazil. The adaptation of the model consisted of the numerical solution of differential equations Streeter-Phelps, considering the effect of incremental flows and sewage releases over the sections, as well as the variability of the sections of rivers and tributaries. For model calibra...

Assessment of the characteristic of nutrients, total metals, and fecal coliform in Sibu Laut River, Sarawak, Malaysia

Science.gov (United States)

Soo, Chen-Lin; Ling, Teck-Yee; Lee, Nyanti; Apun, Kasing

2016-03-01

The concentrations of nutrients (nitrogen and phosphorus), total metals, and fecal coliform (FC) coupling with chlorophyll- a (chl- a), 5-day biochemical oxygen demand (BOD5) and other general environmental parameters were evaluated at the sub-surface and near-bottom water columns of 13 stations in the Sibu Laut River during low and high slack waters. The results indicated that inorganic nitrogen (mainly nitrate) was the primary form of nitrogen whereas organic phosphorus was the major form of phosphorus. The abundance of total heavy metals in Sibu Laut River and its tributaries was in the order of Pb < Cu < Zn < Cd. Fecal coliform concentration was relatively low along Sibu Laut River. The shrimp farm effluents contributed a substantial amount of chl- a, BOD5, nutrients, and FC to the receiving creek except for total metals. Nevertheless, the influence was merely noticeable in the intake creek and amended rapidly along Selang Sibu River and brought minimal effects on the Sibu Laut River. Besides, the domestic sewage effluents from villages nearby also contributed a substantial amount of pollutants.

Exercise training reduces peripheral arterial stiffness and myocardial oxygen demand in young prehypertensive subjects.

Science.gov (United States)

Beck, Darren T; Martin, Jeffrey S; Casey, Darren P; Braith, Randy W

2013-09-01

Large artery stiffness is a major risk factor for the development of hypertension and cardiovascular disease. Persistent prehypertension accelerates the progression of arterial stiffness. Forty-three unmedicated prehypertensive (systolic blood pressure (SBP) = 120-139 mm Hg or diastolic blood pressure (DBP) = 80-89 mm Hg) men and women and 15 normotensive time-matched control subjects (NMTCs; n = 15) aged 18-35 years of age met screening requirements and participated in the study. Prehypertensive subjects were randomly assigned to a resistance exercise training (PHRT; n = 15), endurance exercise training (PHET; n = 13) or time-control group (PHTC; n = 15). Treatment groups performed exercise training 3 days per week for 8 weeks. Pulse wave analysis, pulse wave velocity (PWV), and central and peripheral blood pressures were evaluated before and after exercise intervention or time-matched control. PHRT and PHET reduced resting SBP by 9.6±3.6mm Hg and 11.9±3.4mm Hg, respectively, and DBP by 8.0±5.1mm Hg and 7.2±3.4mm Hg, respectively (P endurance exercise alone effectively reduce peripheral arterial stiffness, central blood pressures, augmentation index, and myocardial oxygen demand in young prehypertensive subjects.

Research progress of on-line automatic monitoring of chemical oxygen demand (COD) of water

Science.gov (United States)

Cai, Youfa; Fu, Xing; Gao, Xiaolu; Li, Lianyin

2018-02-01

With the increasingly stricter control of pollutant emission in China, the on-line automatic monitoring of water quality is particularly urgent. The chemical oxygen demand (COD) is a comprehensive index to measure the contamination caused by organic matters, and thus it is taken as one important index of energy-saving and emission reduction in China’s “Twelve-Five” program. So far, the COD on-line automatic monitoring instrument has played an important role in the field of sewage monitoring. This paper reviews the existing methods to achieve on-line automatic monitoring of COD, and on the basis, points out the future trend of the COD on-line automatic monitoring instruments.

Explorations on Temperature, Oxygen, Nutrients and Habitat Demands of Fish Species Found in River Coruh

Directory of Open Access Journals (Sweden)

Bilal Akbulut

2009-04-01

Full Text Available For the protection of our natural resources, fish species being economic and ecological richness of the natural in the basin of the Çoruh to know their request is extremely a vital important issue. In this study, temperature and oxygen demand, food and habitat of 18 fish species in six families found in river Çoruh assessed and discussed with the literature and database. Limiting the impact of water temperature on the reproductive, growth and nutrition emphasized. The fish species in the basin spawn at temperatures between 14-30°C according to database. Three species belonging to a family feed with animal food floating in the water. The species belonging to the other families more feed mixed with plant and animal foods diet in the floor or near the ground. Importance of their environmental demands has clarified for conservation and sustainable use of these fish species inhabiting in Çoruh River.

Effects of Three Types of Oil Dispersants on Biodegradation of Dispersed Crude Oil in Water Surrounding Two Persian Gulf Provinces

Directory of Open Access Journals (Sweden)

Azadeh Zolfaghari-Baghbaderani

2012-01-01

Full Text Available Objective. To determine the most effective and biodegradable dispersant of spilled oil in water surrounding two Persian Gulf provinces. Methods. This study compared the effects of three dispersants, Pars 1, Pars 2, and Gamlen OD4000 on removal of oil in two Persian Gulf provinces' water. Overall, 16 stations were selected. Using the Well method, the growth rate of isolated bacteria and fungi was identified. To specify the growth rate of microorganisms and their usage of oil in the presence of the above-mentioned dispersants, as exclusive sources of carbon, the bacteria were grown in culture medium for 28 days at 120 rpm, 30∘C, and their optical density was measured by spectrophotometry. Then, we tested biological oxygen demand (BOD and chemical oxygen demand (COD in microorganisms. Results. The highest growth rate was documented for the growth of microorganisms on either Pars 1 or Pars 2 dispersants or their mixtures with oil. However, the culture having microorganisms grown on Pars 1 had higher BOD and COD than the other two dispersants (9200 and 16800 versus 500 and 960, P<0.05. Mixture of oil and Pars 2 as well as oil and Pars 1 dispersants showed the highest BODs and CODs, respectively. In the Bahregan province, microorganisms grown on Pars 2 had maximum amount of BOD and COD in comparison with Pars 1 and Gamlen dispersants (7100 and 15200 versus 6000 and 10560, P<0.05. Conclusion. Pars 1 and Pars 2 were the most effective dispersants with highest degradability comparing Gamlen. In each region, the most suitable compound for removing oil spill from offshores with least secondary contamination should be investigated.

Effects of Three Types of Oil Dispersants on Biodegradation of Dispersed Crude Oil in Water Surrounding Two Persian Gulf Provinces

International Nuclear Information System (INIS)

Zolfaghari-Baghbaderani, A.; Bijani, S.; Zolfaghari-Baghbaderani, A.; Bijani, S.; Emtyazjoo, M.; Emtyazjoo, M.; Poursafa, P.; Mehrabian, S.; Farkhani, D.; Mirmoghtadaee, P.

2012-01-01

Objective. To determine the most effective and biodegradable dispersant of spilled oil in water surrounding two Persian Gulf provinces. Methods. This study compared the effects of three dispersants, Pars 1, Pars 2, and Gamlen OD4000 on removal of oil in two Persian Gulf provinces' water. Overall, 16 stations were selected. Using the Well method, the growth rate of isolated bacteria and fungi was identified. To specify the growth rate of microorganisms and their usage of oil in the presence of the above-mentioned dispersants, as exclusive sources of carbon, the bacteria were grown in culture medium for 28 days at 120 rpm, 30 C, and their optical density was measured by spectrophotometry. Then, we tested biological oxygen demand (BOD) and chemical oxygen demand (COD) in microorganisms. Results. The highest growth rate was documented for the growth of microorganisms on either Pars 1 or Pars 2 dispersants or their mixtures with oil. However, the culture having microorganisms grown on Pars 1 had higher BOD and COD than the other two dispersants (9200 and 16800 versus 500 and 960, P<0.05). Mixture of oil and Pars 2 as well as oil and Pars 1 dispersants showed the highest BODs and CODs, respectively. In the Bahregan province, microorganisms grown on Pars 2 had maximum amount of BOD and COD in comparison with Pars 1 and Gamlen dispersants (7100 and 15200 versus 6000 and 10560, P<0.05). Conclusion. Pars 1 and Pars 2 were the most effective dispersants with highest degradability comparing Gamlen. In each region, the most suitable compound for removing oil spill from off shores with least secondary contamination should be investigated.

Vertical flow constructed wetlands: kinetics of nutrient and organic matter removal.

Science.gov (United States)

Pérez, M M; Hernández, J M; Bossens, J; Jiménez, T; Rosa, E; Tack, F

2014-01-01

The kinetics of organic matter and nutrient removal in a pilot vertical subsurface wetland with red ferralitic soil as substrate were evaluated. The wetland (20 m(2)) was planted with Cyperus alternifolius. The domestic wastewater that was treated in the wetland had undergone a primary treatment consisting of a septic moat and a buffer tank. From the sixth week of operation, the performance of the wetland stabilized, and a significant reduction in pollutant concentration of the effluent wastewater was obtained. Also a significant increase of dissolved oxygen (5 mg/l) was obtained. The organic matter removal efficiency was greater than 85% and the nutrient removal efficiency was greater than 75% in the vertical subsurface wetland. Nitrogen and biochemical oxygen demand (BOD) removal could be described by a first-order model. The kinetic constants were 3.64 and 3.27 d(-1) for BOD and for total nitrogen, respectively. Data on the removal of phosphorus were adapted to a second-order model. The kinetic constant was 0.96 (mg/l)(-1) d(-1). The results demonstrated the potential of vertical flow constructed wetlands to clean treated domestic wastewater before discharge into the environment.

Overview of the state of the art of constructed wetlands for decentralized wastewater management in Brazil.

Science.gov (United States)

Machado, A I; Beretta, M; Fragoso, R; Duarte, E

2017-02-01

Conventional wastewater treatment plants (WWTPs) commonly require large capital investments as well as operation and maintenance costs. Constructed wetlands (CWs) appear as a cost-effective treatment, since they can remove a broad range of contaminants by a combination of physical, chemical and biological processes with a low cost. Therefore, CWs can be successfully applied for decentralized wastewater treatment in regions with low population density and/or with large land availability as Brazil. The present work provides a review of thirty nine studies developed on CWs implemented in Brazil to remove wastewater contaminants. Brazil current sanitation data is also considered to evaluate the potential role of CWs as decentralized wastewater treatment. Performance of CWs was evaluated according to (i) type of wetland system, (ii) different support matrix (iii) vegetation species and (iv) removal efficiency of chemical oxygen demand (COD), biological oxygen demand (BOD 5 ), nitrogen (N), and phosphorus (P). The reviewed CWs in overall presented good efficiencies, whereas H-CWs achieved the highest removals for P, while the higher results for N were attained on VF-CW and for COD and BOD 5 on HF-CW. Therefore, was concluded that CWs are an interesting solution for decentralized wastewater treatment in Brazil since it has warm temperatures, extensive radiation hours and available land. Additionally, the low percentage of population with access to the sewage network in the North and Northeast regions makes these systems especially suitable. Hence, the further implementation of CW is encouraged by the authors in regions with similar characteristics as Brazil. Copyright © 2016 Elsevier Ltd. All rights reserved.

Anthropogenic influence on surface water quality of the Nhue and Day sub-river systems in Vietnam.

Science.gov (United States)

Hanh, Pham Thi Minh; Sthiannopkao, Suthipong; Kim, Kyoung-Woong; Ba, Dang The; Hung, Nguyen Quang

2010-06-01

In order to investigate the temporal and spatial variations of 14 physical and chemical surface water parameters in the Nhue and Day sub-river systems of Vietnam, surface water samples were taken from 43 sampling sites during the dry and rainy seasons in 2007. The results were statistically examined by Mann-Whitney U-test and hierarchical cluster analysis. The results show that water quality of the Day River was significantly improved during the rainy season while this was not the case of the Nhue River. However, the river water did not meet the Vietnamese surface water quality standards for dissolved oxygen (DO), biological oxygen demand (BOD(5)), chemical oxygen demand (COD), nutrients, total coliform, and fecal coliform. This implies that the health of local communities using untreated river water for drinking purposes as well as irrigation of vegetables may be at risk. Forty-three sampling sites were grouped into four main clusters on the basis of water quality characteristics with particular reference to geographic location and land use and revealed the contamination levels from anthropogenic sources.

A cold plasma plume with a highly conductive liquid electrode

International Nuclear Information System (INIS)

Chen Guangliang; Chen Wenxing; Chen Shihua; Yang Size

2008-01-01

A cold dielectric barrier discharge (DBD) plasma plume with one highly conductive liquid electrode has been developed to treat thermally sensitive materials, and its preliminary discharging characteristics have been studied. The averaged electron temperature and density is estimated to be 0.6eV and 10 11 /cm 3 , respectively. The length of plasma plume can reach 5 cm with helium gas (He), and the conductivity of the outer electrode affects the plume length obviously. This plasma plume could be touched by bare hand without causing any burning or painful sensation, which may provide potential application for safe aseptic skin care. Moreover, the oxidative particles (e.g., OH, O * , O 3 ) in the downstream oxygen (O2) gas of the plume have been applied to treat the landfill leachate. The results show that the activated O 2 gas can degrade the landfill leachate effectively, and the chemical oxygen demand (COD), conductivity, biochemical oxygen demand (BOD), and suspended solid (SS) can be decreased by 52%, 57%, 76% and 92%, respectively. (fluids, plasmas and electric discharges)

Eletrólise de resíduos poluidores: I - Efluente de uma indústria liofilizadora de condimentos Electrolysis of polluting wastes: I - Wastewater from a seasoning freeze-drying industry

Directory of Open Access Journals (Sweden)

Dejanira F. de Angelis

1998-02-01

Full Text Available Wastewater from a seasoning freeze-drying industry was electrolysed to increase its biodegradability. Stainless-steel electrodes were used at 9.09 A/m², for up to 80 min. Conductivity, pH, biochemical (BOD and chemical (COD oxygen demands, Daphnia similis acute toxicity bioassays, and bacteria counting through the plate count agar method were determined after different times of electrolysis. The results (e.g. higher BOD and lower COD showed that the biodegradability of the wastewater was significantly increased; furthermore, Fe2+ ions liberated by the electrodes cause microorganisms to die and, when oxidised to Fe3+, contribute for the flocculation and sedimentation of solid residues.

Future butanes supply/demand

International Nuclear Information System (INIS)

Whitley, S.C.

1992-01-01

This paper graphically depicts, through in-depth supply/demand analysis, how environmental regulations can be both bad and good for an industry. In the case of n-butane, the Environmental Protection Agency (EPA) summertime gasoline volatility regulations are a culprit - threatening to ultimately destroy refinery demand for the product as a gasoline blendstock. Waiting in the wings are environmental regulations that should eventually prove to be n-butane's savior. The regulations referred to here are the Clean Air Act (CAA) of 1990's mandate for motor fuel oxygenates. The negative impact of gasoline volatility regulations on U.S. n-butane demand and the positive impact that should come from the use of n-butane as a MTBE precursor are covered. Many variables exist which make studying the effects of these environmental regulations very difficult. Over the past three years RPC Group has conducted numerous studies on n-butane supply/demand, as impacted by both EPA gasoline volatility and fuel oxygenate regulations

Chromium (VI) biosorption and removal of chemical oxygen demand by Spirulina platensis from wastewater-supplemented culture medium.

Science.gov (United States)

Magro, Clinei D; Deon, Maitê C; De Rossi, Andreia; Reinehr, Christian O; Hemkemeier, Marcelo; Colla, Luciane M

2012-01-01

The inappropriate discharge of wastewater containing high concentrations of toxic metals is a serious threat to the environment. Given that the microalga Spirulina platensis has demonstrated a capacity for chromium VI (Cr (VI) biosorption, we assessed the ideal concentration of chromium-containing wastewater required for maximum removal of Cr (VI) and chemical oxygen demand (COD) from the environment by using this microalga. The Paracas and Leb-52 strains of S. platensis, with initial wastewater concentrations of 0%, 12.5%, 25%, and 50%, were cultured in Zarrouk medium diluted to 50% under controlled air, temperature, and lighting conditions. The cultures were maintained for 28 days, and pH, biomass growth, COD, and Cr (VI) were assessed. The wastewater concentration influenced microalgal growth, especially at high concentrations. Removal of 82.19% COD and 60.92% Cr (VI) was obtained, but the COD removal was greater than the Cr (VI) removal in both strains of S. platensis.

Characterization of domestic graywater and graywater solids.

Science.gov (United States)

Sievers, Jan Christian; Londong, Jörg

2018-03-01

The knowledge of loads and concentrations is fundamental for the design of graywater treatment units, but the data on the characteristics of graywater and in particular graywater solids are weak. As general design values regarding graywater treatment facilities are not available for Germany, the objective of this article is to elaborate the characteristics of graywater and graywater solids. This paper describes the results of six sampling campaigns carried out on graywater systems in the German cities Berlin, Lübeck and Kiel. All graywater samples were collected proportional to the flow and the graywater solids were gathered separately. The collected data include graywater volumes and characteristics regarding the organic pollution (chemical oxygen demand (COD), 5-day biochemical oxygen demand (BOD 5 )) and nutrients (total nitrogen (TN), total phosphorus (TP)). The graywater volume fluctuated depending on the location. The specific average flow was 68 litre per inhabitant per day (L/inh.d). Inhabitant-specific loads of 49.3 gCOD t /inh·d, 28 gBOD 5 /inh.d, 1 gTN t /inh.d and 0.38 gTP t /inh.d (subscript 't' = total) were found. Information about the composition of graywater solids in terms of quantity and quality is seriously lacking. Therefore, graywater solids were examined with respect to organic matter (COD) and nutrients (TN, TP). The contribution of graywater solids with particle sizes over 200 microns in relation to the total inhabitant-specific load was approximately 3-8% depending on the parameter. The qualitative and quantitative characteristics of the investigated graywater fractions may serve as a base for the estimation of design values.

COMPARATIVE PERFORMANCE OF SAND AND COCONUT SUBSTRATE IN URBAN WASTEWATER TREATMENT PERFORMANCES COMPAREES DU SABLE ET DU SUBSTRAT DE COCO EN TRAITEMENT D’EAUX RESIDUAIRES URBAINES

Directory of Open Access Journals (Sweden)

MARTINE KONE

2015-05-01

Full Text Available Urban wastewater has been treated by infiltration-percolation on sand and on coconut substrate, in order to highlight their comparative performance. The pilots were fed to the hydraulic loading rate of 40 L·m-2·d-1 during three days a week and kept at rest the next four days. Parameters are measured on an average sample of 24 hours taken on the output of each pilot at the end of the third day of treatment. The average removal efficiencies of chemical oxygen demand (COD were respectively, 94.8 and 39.61 % with the sand and the coconut substrate while the average yields of biochemical oxygen demand (BOD5 were 99.01 and 98.12 %. The results showed that the average removal efficiencies of fecal coliform bacteria were respectively, 98.8 and 91 %. Conductivities have increased by an average of 39.88 % with the sand and 4.65 % with coconut substrate.

Evaluation of electricity generation from lignin residue and biogas in cellulosic ethanol production.

Science.gov (United States)

Liu, Gang; Bao, Jie

2017-11-01

This study takes the first insight on the rigorous evaluation of electricity generation based on the experimentally measured higher heating value (HHV) of lignin residue, as well as the chemical oxygen demand (COD) and biological oxygen demand (BOD 5 ) of wastewater. For producing one metric ton of ethanol fuel from five typical lignocellulose substrates, including corn stover, wheat straw, rice straw, sugarcane bagasse and poplar sawdust, 1.26-1.85tons of dry lignin residue is generated from biorefining process and 0.19-0.27tons of biogas is generated from anaerobic digestion of wastewater, equivalent to 4335-5981kWh and 1946-2795kWh of electricity by combustion of the generated lignin residue and biogas, respectively. The electricity generation not only sufficiently meets the electricity needs of process requirement, but also generates more than half of electricity surplus selling to the grid. Copyright © 2017 Elsevier Ltd. All rights reserved.

Phytoremediation of industrial mines wastewater using water hyacinth.

Science.gov (United States)

Saha, Priyanka; Shinde, Omkar; Sarkar, Supriya

2017-01-02

The wastewater at Sukinda chromite mines (SCM) area of Orissa (India) showed high levels of toxic hexavalent chromium (Cr VI). Wastewater from chromium-contaminated mines exhibit potential threats for biotic community in the vicinity. The aim of the present investigation is to develop a suitable phytoremediation technology for the effective removal of toxic hexavalent chromium from mines wastewater. A water hyacinth species Eichhornia crassipes was chosen to remediate the problem of Cr (VI) pollution from wastewater. It has been observed that this plant was able to remove 99.5% Cr (VI) of the processed water of SCM in 15 days. This aquatic plant not only removed hexavalent Cr, but is also capable of reducing total dissolved solids (TDS), biological oxygen demand (BOD), chemical oxygen demand (COD), and other elements of water also. Large-scale experiment was also performed using 100 L of water from SCM and the same removal efficiency was achieved.

Phytoremediation of industrial mines wastewater using water hyacinth

Science.gov (United States)

Saha, Priyanka; Shinde, Omkar; Sarkar, Supriya

2017-01-01

ABSTRACT The wastewater at Sukinda chromite mines (SCM) area of Orissa (India) showed high levels of toxic hexavalent chromium (Cr VI). Wastewater from chromium-contaminated mines exhibit potential threats for biotic community in the vicinity. The aim of the present investigation is to develop a suitable phytoremediation technology for the effective removal of toxic hexavalent chromium from mines wastewater. A water hyacinth species Eichhornia crassipes was chosen to remediate the problem of Cr (VI) pollution from wastewater. It has been observed that this plant was able to remove 99.5% Cr (VI) of the processed water of SCM in 15 days. This aquatic plant not only removed hexavalent Cr, but is also capable of reducing total dissolved solids (TDS), biological oxygen demand (BOD), chemical oxygen demand (COD), and other elements of water also. Large-scale experiment was also performed using 100 L of water from SCM and the same removal efficiency was achieved. PMID:27551860

Demonstration of an Environmentally Benign and Reduced Corrosion Runway Deicing Fluid

Science.gov (United States)

2011-01-01

43201 8. PERFORMING ORGANIZATION REPORT NUMBER 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) Enviromental Security Technology...Center for Engineering and the Environment AFCESA Air Force Civil Engineering Support Agency AFI Air Force Instruction AFMC Air Force Materiel Command...American Society for Testing and Materials BOD Biochemical Oxygen Demand CRREL Cold Regions Research and Engineering Laboratory CFR Code of

Effects of three types of oil dispersants on biodegradation of dispersed crude oil in water surrounding two Persian gulf provinces.

Science.gov (United States)

Zolfaghari-Baghbaderani, Azadeh; Emtyazjoo, Mozhgan; Poursafa, Parinaz; Mehrabian, Sedigheh; Bijani, Samira; Farkhani, Daryoush; Mirmoghtadaee, Parisa

2012-01-01

To determine the most effective and biodegradable dispersant of spilled oil in water surrounding two Persian Gulf provinces. This study compared the effects of three dispersants, Pars 1, Pars 2, and Gamlen OD4000 on removal of oil in two Persian Gulf provinces' water. Overall, 16 stations were selected. Using the Well method, the growth rate of isolated bacteria and fungi was identified. To specify the growth rate of microorganisms and their usage of oil in the presence of the above-mentioned dispersants, as exclusive sources of carbon, the bacteria were grown in culture medium for 28 days at 120 rpm, 30°C, and their optical density was measured by spectrophotometry. Then, we tested biological oxygen demand (BOD) and chemical oxygen demand (COD) in microorganisms. The highest growth rate was documented for the growth of microorganisms on either Pars 1 or Pars 2 dispersants or their mixtures with oil. However, the culture having microorganisms grown on Pars 1 had higher BOD and COD than the other two dispersants (9200 and 16800 versus 500 and 960, P microorganisms grown on Pars 2 had maximum amount of BOD and COD in comparison with Pars 1 and Gamlen dispersants (7100 and 15200 versus 6000 and 10560, P < 0.05). Pars 1 and Pars 2 were the most effective dispersants with highest degradability comparing Gamlen. In each region, the most suitable compound for removing oil spill from offshores with least secondary contamination should be investigated.

Soil aquifer treatment of artificial wastewater under saturated conditions

KAUST Repository

Essandoh, H. M K

2011-05-01

A 2000 mm long saturated laboratory soil column was used to simulate soil aquifer treatment under saturated conditions to assess the removal of chemical and biochemical oxygen demand (COD and BOD), dissolved organic carbon (DOC), nitrogen and phosphate, using high strength artificial wastewater. The removal rates were determined under a combination of constant hydraulic loading rates (HLR) and variable COD concentrations as well as variable HLR under a constant COD. Within the range of COD concentrations considered (42 mg L-1-135 mg L-1) it was found that at fixed hydraulic loading rate, a decrease in the influent concentrations of dissolved organic carbon (DOC), biochemical oxygen demand (BOD), total nitrogen and phosphate improved their removal efficiencies. At the high COD concentrations applied residence times influenced the redox conditions in the soil column. Long residence times were detrimental to the removal process for COD, BOD and DOC as anoxic processes and sulphate reduction played an important role as electron acceptors. It was found that total COD mass loading within the range of 911 mg d-1-1780 mg d-1 applied as low COD wastewater infiltrated coupled with short residence times would provide better effluent quality than the same mass applied as a COD with higher concentration at long residence times. The opposite was true for organic nitrogen where relatively high concentrations coupled with long residence time gave better removal efficiency. © 2011.

Exercise Training Reduces Peripheral Arterial Stiffness and Myocardial Oxygen Demand in Young Prehypertensive Subjects

Science.gov (United States)

2013-01-01

BACKGROUND Large artery stiffness is a major risk factor for the development of hypertension and cardiovascular disease. Persistent prehypertension accelerates the progression of arterial stiffness. METHODS Forty-three unmedicated prehypertensive (systolic blood pressure (SBP) = 120–139mm Hg or diastolic blood pressure (DBP) = 80–89mm Hg) men and women and 15 normotensive time-matched control subjects (NMTCs; n = 15) aged 18–35 years of age met screening requirements and participated in the study. Prehypertensive subjects were randomly assigned to a resistance exercise training (PHRT; n = 15), endurance exercise training (PHET; n = 13) or time-control group (PHTC; n = 15). Treatment groups performed exercise training 3 days per week for 8 weeks. Pulse wave analysis, pulse wave velocity (PWV), and central and peripheral blood pressures were evaluated before and after exercise intervention or time-matched control. RESULTS PHRT and PHET reduced resting SBP by 9.6±3.6mm Hg and 11.9±3.4mm Hg, respectively, and DBP by 8.0±5.1mm Hg and 7.2±3.4mm Hg, respectively (P endurance exercise alone effectively reduce peripheral arterial stiffness, central blood pressures, augmentation index, and myocardial oxygen demand in young prehypertensive subjects. PMID:23736111

Oxygen permeation properties of dense Bi1.5Er0.5O3-Ag cermet membranes

NARCIS (Netherlands)

ten Elshof, Johan E.; Nguyen, N.Q.; den Otter, M.W.; Bouwmeester, Henricus J.M.

1997-01-01

Oxygen permeation experiments were performed on dense mixed-conducting ceramic-metal composite membranes (thickness 0.2 to 2 mm) Bi1.5Er0.5O3-Ag with 10.0, 27.8, and 40.0 volume percent (v/o) silver, respectively, in the temperature range 873 to 993 K and oxygen partial pressure range 10–3.5 to 1

Sediment remediation of the Hespeler Mill Pond, Cambridge, Ontario

Energy Technology Data Exchange (ETDEWEB)

Angeloni, D.; Eby, M.; Jarvis, S.; Martin, P. [Univ. of Guelph, School of Engineering, Guelph, Ontario (Canada)]. E-mail: danielle.angeloni@earthtech.ca

2002-06-15

'Full text:' Low dissolved oxygen levels and large accumulated sediment remediation alternatives were examined to assemble the Hespeler Mill Pond, Cambridge (HMP) into a healthier and more desirable recreational area in the City of Cambridge. The theory that a large amount of sediment has been deposited into the HMP from the Speed River upstream over a number of years predicts the depressed oxygen levels, high nutrient-loading rates and the odour problems in the summer months. The initial phase in the remediation plan for this project involved extensive background research and investigation. The focus was on determining the characteristics of the sediment and the history of the pond, to ultimately decide if the sediment was the source of the issues. Dissolved oxygen field tests and sediment sampling were conducted to get information on the magnitude of the problem and the environmental hazards potentially present in the pond. The pond was modelled utilising the Streeter-Phelps oxygen-sag model to predict the oxygen deficit. Biochemical Oxygen Demand (BOD{sub 5}) testing was completed to determine the oxygen demand in the pond. These tests were conducted by using water samples obtained from various sample points at the pond. The proposed solution is a combined dredging and aeration approach. Mechanical dredging using a clamshell bucket and the installation of aerators is expected to solve the dissolved oxygen and water quality issues. (author)

Enhancement of Biodegradation of Palm Oil Mill Effluents by Local Isolated Microorganisms.

Science.gov (United States)

Soleimaninanadegani, Mohammadreza; Manshad, Soheila

2014-01-01

This study was designed to investigate the microorganisms associated with palm oil mill effluent (POME) in Johor Bahru state, Malaysia. Biodegradation of palm oil mill effluents (POME) was conducted to measure the discarded POME based on physicochemical quality. The bacteria that were isolated are Micrococcus species, Bacillus species, Pseudomonas species, and Staphylococcus aureus, while the fungi that were isolated are Aspergillus niger, Aspergillus fumigatus, Candida species, Fusarium species, Mucor species, and Penicillium species. The autoclaved and unautoclaved raw POME samples were incubated for 7 days and the activities of the microorganisms were observed each 12 hours. The supernatants of the digested POME were investigated for the removal of chemical oxygen demand (COD), color (ADMI), and biochemical oxygen demand (BOD) at the end of each digestion cycle. The results showed that the unautoclaved raw POME sample degraded better than the inoculated POME sample and this suggests that the microorganisms that are indigenous in the POME are more effective than the introduced microorganisms. This result, however, indicates the prospect of isolating indigenous microorganisms in the POME for effective biodegradation of POME. Moreover, the effective treatment of POME yields useful products such as reduction of BOD, COD, and color.

Enhancement of Biodegradation of Palm Oil Mill Effluents by Local Isolated Microorganisms

Science.gov (United States)

Soleimaninanadegani, Mohammadreza

2014-01-01

This study was designed to investigate the microorganisms associated with palm oil mill effluent (POME) in Johor Bahru state, Malaysia. Biodegradation of palm oil mill effluents (POME) was conducted to measure the discarded POME based on physicochemical quality. The bacteria that were isolated are Micrococcus species, Bacillus species, Pseudomonas species, and Staphylococcus aureus, while the fungi that were isolated are Aspergillus niger, Aspergillus fumigatus, Candida species, Fusarium species, Mucor species, and Penicillium species. The autoclaved and unautoclaved raw POME samples were incubated for 7 days and the activities of the microorganisms were observed each 12 hours. The supernatants of the digested POME were investigated for the removal of chemical oxygen demand (COD), color (ADMI), and biochemical oxygen demand (BOD) at the end of each digestion cycle. The results showed that the unautoclaved raw POME sample degraded better than the inoculated POME sample and this suggests that the microorganisms that are indigenous in the POME are more effective than the introduced microorganisms. This result, however, indicates the prospect of isolating indigenous microorganisms in the POME for effective biodegradation of POME. Moreover, the effective treatment of POME yields useful products such as reduction of BOD, COD, and color. PMID:27433516

Oxygen vacancies induced enhancement of photoconductivity of La0.5Sr0.5CoO3 - δ thin film

Science.gov (United States)

Gao, R. L.; Fu, C. L.; Cai, W.; Chen, G.; Deng, X. L.; Yang, H. W.; Sun, J. R.; Zhao, Y. G.; Shen, B. G.

2014-09-01

Effects of light and electrical current on the electrical transport properties and photovoltaic properties of oxygen-stoichiometric La0.5Sr0.5CoO3 and oxygen-deficient La0.5Sr0.5CoO3 - δ films prepared by pulsed laser deposition have been investigated. Oxygen-deficient films annealed in a vacuum show an obvious increase of resistance and lattice parameter. Besides, a direct correlation between the magnitude of the photoconductivity and oxygen vacancies in La0.5Sr0.5CoO3 - δ films has been observed. The light illumination causes a resistance drop to show the photoconductivity effect. Moreover, the photoconductivity can be remarkably enhanced by increasing the electrical current, that is, it exhibits current-enhanced photoconductivity (CEPC) effect. Oxygen deficiency in the annealed film leads to the formation of a structural disorder in the Co-O-Co conduction channel due to the accumulated oxygen vacancies and hence is believed to be responsible for the increase in higher photoconductivity. These results may be important for practical applications in photoelectric devices.

Physicochemical Characteristics of Pennar River, A Fresh Water Wetland in Kerala, India

Directory of Open Access Journals (Sweden)

P. V. Joseph

2010-01-01

Full Text Available Some physicochemical characteristics of a fresh water wetland were investigated. The analysis was carried out for a period of two years. Physical parameters such as colour, odour, temperature, electrical conductivity (EC total suspended solids (TSS total dissolved substances (TDS, total solids (TS, turbidity and chemical parameters such as pH, alkalinity, hardness, dissolved oxygen (DO, biochemical oxygen demand (BOD, chemical oxygen demand (COD, chloride, salinity, flouride, phosphate & nitrate were examined. Results of the study indicated that water in Pennar river is highly contaminated and not safe for drinking. Uncontrolled use of chemical fertilizers and pesticides, unscrupulous dumping of domestic wastes are the major causes of deterioration of water. Poor quality of drinking water was recorded as the major risk factor for the large-scale water-borne diseases in the area.

Bio-adsorption (Pilot-scale). Investigation of cleansing effect and sludge formation. [Municipal wastes]. Biosorption. Pilot-skala. Undersoegelse af renseeffekt og slamudbytte

Energy Technology Data Exchange (ETDEWEB)

1988-07-15

The aim of the project was to investigate the process of bioadsorption in relation to the purifying of sewage waste where the oxygen levels were 0%, 2.5% and 10%. Cleansing results for 2.5% oxygen saturation was 50-70% for BOD and 30-50% for COD. Reduction of nitrogen and phosphorus was 15-20% and 20-25%. 40% of the removed nitrogen, and the organic bound phosphorus, was returned to the system via the internal reject-flow and thus to the biological processing. The tendence to sludge production was heightened where oxygen saturation was moderate. It is reckoned that operational costs were reduced by 10 Danish oere per cubic meter waste water where the unprocessed waste had a content of 250mg BOD/1. (AB).

Effect of oxygen stoichiometry on the electrical properties of La0.5Sr0.5CoO3 electrodes

International Nuclear Information System (INIS)

Madhukar, S.; Aggarwal, S.; Dhote, A.M.; Ramesh, R.; Krishnan, A.; Keeble, D.; Poindexter, E.

1997-01-01

We report on the metal-insulator transition of La 0.5 Sr 0.5 CoO 3 thin films deposited by pulsed laser ablation on LaAlO 3 substrates. The films were cooled in oxygen partial pressures between 760 and 10 -5 Torr and electrical resistivity of the films was measured as a function of cooling oxygen pressure. La 0.5 Sr 0.5 CoO 3 films changed from metallic to insulating behavior depending on their oxygen content. A defect model has been proposed to explain this transition and the change in conductivity is related to the change in the oxidation state of the cobalt ions. The model explains the relationship between oxygen partial pressure and electrical conductivity in La 0.5 Sr 0.5 CoO 3 , which describes the experimental dependence reasonably well. Positron annihilation studies were also done on the same set of samples and the S parameter was seen to increase by 8% from a fully oxygenated sample to a sample cooled in 10 -5 Torr. copyright 1997 American Institute of Physics

Photocatalytic pretreatment of oily wastewater from the restaurant by a vacuum ultraviolet/TiO2 system

International Nuclear Information System (INIS)

Kang Jianxiong; Lu Lu; Zhan Wei; Li Bo; Li Daosheng; Ren Yongzheng; Liu Dongqi

2011-01-01

The present study aims at investigating the performance of a vacuum ultraviolet (VUV, 185 nm) and TiO 2 oxidation system for the pretreatment of oily wastewater from restaurant. The influence of irradiation time, pH, dissolved oxygen (DO), the dosage of TiO 2 and the initial chemical oxygen demand (COD) concentration on COD removal efficiency was ascertained and optimum process conditions for stable and effective operation were determined. Under the optimum conditions of irradiation 10 min, initial COD 3981 mg/L, TiO 2 150 mg/L, pH 7.0 and flow rate of air 40 L/h, the process of VUV and TiO 2 /VUV achieved removal efficiencies of COD, BOD 5 and oil as 50 ± 3%, 37 ± 2%, 86 ± 3%, and 63 ± 3%, 43 ± 2%, 70 ± 3%, respectively. The biodegradability factor f B of the wastewater was determined as 1.56 which indicated that the VUV/TiO 2 process improved the biodegradability of the oily wastewater significantly. Results clearly indicate that VUV/TiO 2 photolysis tends to destruct parts of COD, BOD 5 , and ammonia, as well as enhances the biodegradability of the oily wastewater simultaneously. Thus, this technique could be used as a pretreatment step for conventional biological treatment of oily wastewater.

Photocatalytic pretreatment of oily wastewater from the restaurant by a vacuum ultraviolet/TiO2 system.

Science.gov (United States)

Kang, Jian-xiong; Lu, Lu; Zhan, Wei; Li, Bo; Li, Dao-sheng; Ren, Yong-zheng; Liu, Dong-qi

2011-02-15

The present study aims at investigating the performance of a vacuum ultraviolet (VUV, 185 nm) and TiO(2) oxidation system for the pretreatment of oily wastewater from restaurant. The influence of irradiation time, pH, dissolved oxygen (DO), the dosage of TiO(2) and the initial chemical oxygen demand (COD) concentration on COD removal efficiency was ascertained and optimum process conditions for stable and effective operation were determined. Under the optimum conditions of irradiation 10 min, initial COD 3981 mg/L, TiO(2) 150 mg/L, pH 7.0 and flow rate of air 40 L/h, the process of VUV and TiO(2)/VUV achieved removal efficiencies of COD, BOD(5) and oil as 50±3%, 37±2%, 86±3%, and 63±3%, 43±2%, 70±3%, respectively. The biodegradability factor f(B) of the wastewater was determined as 1.56 which indicated that the VUV/TiO(2) process improved the biodegradability of the oily wastewater significantly. Results clearly indicate that VUV/TiO(2) photolysis tends to destruct parts of COD, BOD(5), and ammonia, as well as enhances the biodegradability of the oily wastewater simultaneously. Thus, this technique could be used as a pretreatment step for conventional biological treatment of oily wastewater. Copyright © 2010 Elsevier B.V. All rights reserved.

Nitrogen and chemical oxygen demand removal from septic tank wastewater in subsurface flow constructed wetlands: substrate (cation exchange capacity) effects.

Science.gov (United States)

Collison, Robert S; Grismer, Mark E

2014-04-01

The current article focuses on chemical oxygen demand (COD) and nitrogen (ammonium and nitrate) removal performance from synthetic human wastewater as affected by different substrate rocks having a range of porosities and cation exchange capacities (CECs). The aggregates included lava rock, lightweight expanded shale, meta-basalt (control), and zeolite. The first three had CECs of 1 to 4 mequiv/100 gm, whereas the zeolite CEC was much greater (-80 mequiv/100 gm). Synthetic wastewater was gravity fed to each constructed wetland system, resulting in a 4-day retention time. Effluent samples were collected, and COD and nitrogen species concentrations measured regularly during four time periods from November 2008 through June 2009. Chemical oxygen demand and nitrogen removal fractions were not significantly different between the field and laboratory constructed wetland systems when corrected for temperature. Similarly, overall COD and nitrogen removal fractions were practically the same for the aggregate substrates. The important difference between aggregate effects was the zeolite's ammonia removal process, which was primarily by adsorption. The resulting single-stage nitrogen removal process may be an alternative to nitrification and denitrification that may realize significant cost savings in practice.

The effect of industrial effluent stream on the groundwater

International Nuclear Information System (INIS)

Yasar, A.; Ahmad, N.; Chaudhry, M.N.; Sarwar, M.

2005-01-01

This study was performed to investigate the effect of the industrial wastewater stream on the groundwater. Wastewater was characterized in terms of inorganic and organic constituents. Inorganic constituents included Na/sup +/, Ca/sup 2+/ K/sup +/, Cl/sup -/, NO/sub 3//sup -/ and SO/sub 4//sup 2-/ coupled with heavy metal elements such as, Cd, Cr, Pb, Mn, Cu, Ni, Fe and In. Organic load of the stream was determined in terms of chemical oxygen demand (COD), biological oxygen demand (BOD/sub 5/) and ammonia-nitrogen (NH/sub 3/-N) contents. Other characteristics were pH, electrical conductivity (EC) and total dissolved solids (TDS). The correlation coefficients between quality parameter pairs of stream water and groundwater were determined to ascertain the source of groundwater contamination. At station 1, BOD/sub 5/ and COD contents were 20 times and Cr concentration was 10 times higher than the permissible limits for stream water [1]. Contents of these parameters reflected the level of industrial and domestic pollution coming from India. However, large variations in the levels of these parameters at down stream sites of the drain were characteristic of type and nature of industrial effluents and domestic sewage joining the stream. Analysis results of more than one hundred groundwater samples from shallow and deep wells around the drain showed that groundwater of shallow aquifers was contaminated due to drain water. A comparison of the contents of these parameters in shallow wells with WHO standards showed that some parameters such as turbidity, TDS, Na/sup +/, F -and heavy metals like Cr were found higher than the permissible limits. (author)

Chemometrics-assisted spectrophotometry method for the determination of chemical oxygen demand in pulping effluent.

Science.gov (United States)

Chen, Honglei; Chen, Yuancai; Zhan, Huaiyu; Fu, Shiyu

2011-04-01

A new method has been developed for the determination of chemical oxygen demand (COD) in pulping effluent using chemometrics-assisted spectrophotometry. Two calibration models were established by inducing UV-visible spectroscopy (model 1) and derivative spectroscopy (model 2), combined with the chemometrics software Smica-P. Correlation coefficients of the two models are 0.9954 (model 1) and 0.9963 (model 2) when COD of samples is in the range of 0 to 405 mg/L. Sensitivities of the two models are 0.0061 (model 1) and 0.0056 (model 2) and method detection limits are 2.02-2.45 mg/L (model 1) and 2.13-2.51 mg/L (model 2). Validation experiment showed that the average standard deviation of model 2 was 1.11 and that of model 1 was 1.54. Similarly, average relative error of model 2 (4.25%) was lower than model 1 (5.00%), which indicated that the predictability of model 2 was better than that of model 1. Chemometrics-assisted spectrophotometry method did not need chemical reagents and digestion which were required in the conventional methods, and the testing time of the new method was significantly shorter than the conventional ones. The proposed method can be used to measure COD in pulping effluent as an environmentally friendly approach with satisfactory results.

Physiological demands of downhill mountain biking.

Science.gov (United States)

Burr, Jamie F; Drury, C Taylor; Ivey, Adam C; Warburton, Darren E R

2012-12-01

Mountain biking is a popular recreational pursuit and the physiological demands of cross-country style riding have been well documented. However, little is known regarding the growing discipline of gravity-assisted downhill cycling. We characterised the physiological demands of downhill mountain biking under typical riding conditions. Riding oxygen consumption (VO(2)) and heart rate (HR) were measured on 11 male and eight female experienced downhill cyclists and compared with data during a standardised incremental to maximum (VO(2max)) exercise test. The mean VO(2) while riding was 23.1 ± 6.9 ml · kg(-1) · min(-1) or 52 ± 14% of VO(2max) with corresponding heart rates of 146 ± 11 bpm (80 ± 6% HRmax). Over 65% of the ride was in a zone at or above an intensity level associated with improvements in health-related fitness. However, the participants' heart rates and ratings of perceived exertion were artificially inflated in comparison with the actual metabolic demands of the downhill ride. Substantial muscular fatigue was evident in grip strength, which decreased 5.4 ± 9.4 kg (5.5 ± 11.2%, P = 0.03) post-ride. Participation in downhill mountain biking is associated with significant physiological demands, which are in a range associated with beneficial effects on health-related fitness.

Removal of nitrogen and organic matter in a submerged-membrane bioreactor operating in a condition of simultaneous nitrification and denitrification

Directory of Open Access Journals (Sweden)

Izabela Major Barbosa

2016-04-01

Full Text Available This study evaluated the removal of nitrogen and organic matter in a membrane bioreactor system operating in a condition of simultaneous nitrification and denitrification controlled by intermittent aeration. A submerged-membrane system in a bioreactor was used in a pilot scale to treat domestic wastewater. The dissolved oxygen concentration was maintained between 0.5 and 0.8 mg L-1. The concentration of the mixed liquor suspended solids (MLSS in the system ranged from 1 to 6 g L-1. The system efficiency was evaluated by the removal efficiency of organic matter, quantified by Chemical Oxygen Demand (COD, Biochemical Oxygen Demand (BOD5 and Total Organic Carbon (TOC. Nitrogen removal was assessed by quantifying Total Kjeldahl Nitrogen (TKN and ammonia nitrogen. During the system start-up, the removal efficiencies of COD and NTK were around 90% and 80%, respectively. After the simultaneous nitrification and denitrification (SND conditions were established, the removal efficiencies of COD and NTK were 70% and 99%, respectively. These results showed that sewage treatment with the membrane bioreactor (MBR system, operating with simultaneous nitrification and denitrification conditions, was able to remove organic matter and promote nitrification and denitrification in a single reactor, producing a high-quality permeate.

The chemical and biological characteristics of coke-oven wastewater by ozonation

International Nuclear Information System (INIS)

Chang, E.-E.; Hsing, H.-J.; Chiang, P.-C.; Chen, M.-Y.; Shyng, J.-Y.

2008-01-01

A bench-scale bubble column reactor was used to investigate the biological and chemical characteristics of coke-oven wastewater after ozonation treatment through the examination of selected parameters. Color and thiocyanate could be removed almost entirely; however, organic matter and cyanide could not, due to the inadequate oxidation ability of ozone to remove ozonated byproducts under given experimental conditions. The removal of cyanide and total organic carbon were pH-dependent and were found to be efficient under neutral to alkaline conditions. The removal rate for thiocyanate was about five times that of cyanide. The ozone consumption ratio approached to about 1 at the early stage of ozonation (time TOC ) increased to 30%, indicating that easily degraded pollutants were degraded almost entirely. The effect of ozonation on the subsequent biological treatment unit (i.e., activated sludge process) was determined by observing the ratio of 5-day biological oxygen demand to chemical oxygen demand (BOD 5 /COD) and the specific oxygen utilization rate (SOUR). The results indicated that the contribution of ozonation to inhibition reduction was very significant but limited to the enhancement of biodegradation. The operation for ozonation of coke-oven wastewater was feasible under neutral condition and short ozone contact time in order to achieve better performance and cost savings

A determination of the oxygen non-stoichiometry of the oxygen storage materials LnBaMn2O5+δ (Ln=Gd, Pr)

Science.gov (United States)

Jeamjumnunja, Kannika; Gong, Wenquan; Makarenko, Tatyana; Jacobson, Allan J.

2016-07-01

The A-site ordered double-perovskite oxides, LnBaMn2O5+δ (Ln=Gd, Pr), were synthesized and investigated to understand the effect of A site cation substitution on the oxygen storage properties of these materials. The present results are compared with our previous data for YBaMn2O5+δ. The results clearly reveal that changing the Ln cation strongly influences the oxidation/reduction behavior of LnBaMn2O5+δ. Based on thermogravimetric analysis data, oxygen uptake begins at lower temperatures in both air and oxygen in compounds with Ln3+ ions larger than Y3+. These oxides exhibit almost complete and reversible oxygen uptake/release between fully-reduced LnBaMn2O5 and fully-oxidized LnBaMn2O6 during changes of the oxygen partial pressure between air and 1.99% H2/Ar. In addition, the oxygen non-stoichiometries of GdBaMn2O5+δ and PrBaMn2O5+δ were determined as a function of pO2 at 600, 650, 700 and 750 °C by Coulometric titration at near-equilibrium conditions. The results confirm that these materials have two distinct phases on oxidation/reduction with δ≈0, 0.5 and a third phase with a range of composition with an oxygen content (5+δ) approaching 6. The stabilities of the LnBaMn2O5+δ phases extend over a wide range of oxygen partial pressures (∼10-25≤pO2 (atm)≤∼1) depending on temperature. Isothermal experiments show that the larger the Ln3+ cation the lower pO2 for phase conversion. At some temperatures and pO2 conditions, the LnBaMn2O5+δ compounds are unstable with respect to decomposition to BaMnO3-δ and LnMnO3. This instability is more apparent in Coulometric titration experiments than in thermogravimetric analysis. The Coulometric titration experiments are necessarily slow in order to achieve equilibrium oxygen compositions.

Hydrogen peroxide-enhanced iron-mediated aeration for the treatment of mature landfill leachate.

Science.gov (United States)

Deng, Yang; Englehardt, James D

2008-05-01

Municipal landfill leachate is being disallowed for biological treatment by some sewer authorities due to its recalcitrance and corrosiveness, and therefore physicochemical treatment may be needed. In this paper, hydrogen peroxide-enhanced iron (Fe(0))-mediated aeration (IMA) was studied as an alternative for the treatment of mature landfill leachate. Bench-scale Taguchi array screening tests and full factorial tests were conducted. Iron grade, initial pH, H(2)O(2) addition rate, and aeration rate significantly influenced both overall chemical oxygen demand (COD) removal and iron consumption. In the enhanced IMA-treated leachate at an initial pH of 8.2, COD was reduced by 50% due to oxidation and coagulation, a level almost equivalent to those obtained by Fenton treatment. Meanwhile, the 5-day biochemical oxygen demand (BOD(5))/COD ratio was increased from 0.02 to 0.17. In particular, the effect of initial pH became minor at H(2)O(2) addition rate greater than the theoretical demand for complete oxidation of organics by H(2)O(2). In addition, 83% of 300 mg/L ammonia nitrogen and 38% of 8.30 mS/cm electrical conductivity were removed when the initial pH was not adjusted. Based on these results, the process appears suitable for treatment of mature leachate.

Embrittlement of the alloy U 7.5 Nb 2.5 Zr by gaseous oxygen and hydrogen

International Nuclear Information System (INIS)

Lepoutre, D.; Nomine, A.M.; Miannay, D.

1981-04-01

Embrittlement of the alloy uranium 7.5 niobium 2.5 zirconium in gaseous oxygen and hydrogen versus stress intensity, temperature and pressure is studied using rupture mechanics. Cracking speed is determined. In oxygen, only cracks are produced and embrittlement is due to oxidation. In hydrogen at high pressure an hydride is formed and at low pressure cracks are produced but the mechanism is not identified [fr

Effect of dietary crude protein levels in a commercial range, on the nitrogen balance, ammonia emission and pollutant characteristics of slurry in fattening pigs.

Science.gov (United States)

Hernández, F; Martínez, S; López, C; Megías, M D; López, M; Madrid, J

2011-06-01

An experiment was conducted to investigate the effect of dietary levels of crude protein (CP), close to the range used commercially and to the European Commission recommended values, on the nitrogen (N) balance, ammonia (NH(3)) emission and pollutant characteristics of the slurry from growing and finishing pigs. Three feeding programmes with different CP levels were compared during the growing and the finishing periods of fattening. Diets were formulated to be isoenergetic and for the digestible lysine : metabolisable energy ratio to be similar in all the diets for each phase, but differed in CP concentration (160, 150 and 140 g CP/kg for the growing phase and 155, 145 and 135 g CP/kg for the finishing phase). Faeces and urine from barrows (eight replicates per diet) allocated in metabolism cages were collected separately for 5 days to calculate the N balance and for 2 days to measure NH(3) emission in a laboratory system for 240 h. Excreta were analysed for pH, volatile fatty acids (VFA), total N, electrical conductivity (EC), total solids (TS), volatile solids (VS), biochemical oxygen demand (BOD(5)), chemical oxygen demand (COD) and NH(4)-N reduction of dietary CP content led to a linear decrease of urinary (P 0.05) during the 240 h of study. However, in the growing phase, the NH(3)-N level in slurry was lower (P 0.05) on total VFA, EC, TS, VS, COD or BOD(5) contents of excreta. These parameters were higher (P commercial diets and close to the European Commission recommended values will decrease urinary and total N excretion in the slurry of growing-finishing pigs. The slurry from finishing pigs is more concentrated than that from growing pigs.

Oxygen rocking aqueous batteries utilizing reversible topotactic oxygen insertion/extraction in iron-based perovskite oxides Ca(1-x)La(x)FeO(3-δ).

Science.gov (United States)

Hibino, Mitsuhiro; Kimura, Takeshi; Suga, Yosuke; Kudo, Tetsuichi; Mizuno, Noritaka

2012-01-01

Developments of large-scale energy storages with not only low cost and high safety but also abundant metals are significantly demanded. While lithium ion batteries are the most successful method, they cannot satisfy all conditions. Here we show the principle of novel lithium-free secondary oxygen rocking aqueous batteries, in which oxygen shuttles between the cathode and anode composed of iron-based perovskite-related oxides Ca(0.5)La(0.5)FeO(z) (2.5 ≤ z ≤ 2.75 and 2.75 ≤ z ≤ 3.0). Compound Ca(0.5)La(0.5)FeO(z) can undergo two kinds of reduction and reoxidation of Fe(4+)/Fe(3+) and Fe(3+)/Fe(2+), that are accompanied by reversible and repeatable topotactic oxygen extraction and reinsertion during discharge and charge processes.

Mineral and organic compounds in leachate from landfill with concentrate recirculation.

Science.gov (United States)

Talalaj, Izabela Anna

2015-02-01

The effect of a reverse osmosis concentrate recirculation on the mineral and organic compounds in a landfill leachate was investigated. Investigated was the quality of a leachate from two landfills operated for different periods (a 20-year-old Cell A and a 1-year-old Cell B), where the concentrate was recirculated. Examined were general parameters (conductivity, pH), organic compounds (biochemical oxygen demand (BOD), chemical oxygen demand (COD), total organic nitrogen, BOD/COD), and inorganic compounds (nitrogen ammonia, sulfite, sulfate, cyanide, boron, chloride, ferrous, zinc, chrome, copper). The findings from the first year of investigation showed that over the initial period of recirculation, the concentration of organic compounds (BOD, COD) increased, but after 6 months their values stabilized. It indicates that the concentrate recirculation accelerated organic decomposition, especially in the new landfill Cell. The analysis of inorganic parameters showed that recirculation landfills produce a leachate with a higher concentration of N-NH4, and Cl(-). In case of the old landfill Cell, an increase in B and Fe was also noticeable. These compounds are cyclically washed out from a waste dump and require an additional pretreatment in order to exclude them from recirculation cycle. The increased concentration of Cu, Zn, and Fe was noticed during the initial months of recirculation and in the season of intense atmospheric precipitation in the leachate from both Cells. Higher values of electro conductivity, Cl(-), N-NH4 (+), B, and Fe in the leachate from the old field indicate that the attenuation capacity of this landfill is close to exhaustion.

Recycling of canteen waste water for irrigation purpose

International Nuclear Information System (INIS)

Ahmad, J.

2005-01-01

Recycling of wastewater of a canteen was done at Attock refinery Limited, Rawalpindi during 2002. The wastewater of the refinery canteen was recycled after a long process and was reused for irrigation of nearby garden and other landscape plants. The average outflow of the wastewater from the canteen was calculated as 4000 liters/day. Laboratory analysis for the quality of wastewater was conducted and it was found that suspended solid. Chemical Oxygen demand (COD) and biochemical oxygen demand (BOD) of the wastewater were above the National Environmental Quality Standards (NEQS) limits. Treatment system employed was composed of screening and settling tank for removing the suspended solids and aeration for decreasing the COD and BOD. It was a low cost system in which the materials used were mostly taken from the redundant stock. Air was given for aeration with the help of a compressor. The treated water was tested in the laboratory for the priority parameters i.e. temperature, pH, BOD, COD, Total suspended solids (TSS), Total dissolved (TDS), oil and grease and Phenols. These parameters were compared with the National Environmental Quality Standards (NEQS). Treated water was used for irrigation of the nearby garden and landscape. The recycling process was successfully conducted and a huge quantity of 4000 liters water/day (1000 G water/day) was processes was successfully conducted and a huge quantity of 4000 liters water/day (1000 G water/day) was recycled with a daily saving of Rs.100 at the rate of Rs.1/10 G water that was taken from market survey. (author)

Characterization of Wastewaters obtained from Hatay Tanneries

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Şana Sungur

2017-06-01

Full Text Available The leather tanning industry is one of the most significant pollutants in terms of both conventional and toxic parameters. On the other hand, leather industry has an important economic role both in Turkey and in the World. In this study, wastewater samples were taken from 15 different tanneries in the Hatay Region. Wastewaters obtained from liming process and chromium tanning process was analyzed. Sulfide, chromium (III, chromium (VI, oil and grease, total suspended solids (TSS, organic matters, biochemical oxygen demand (BOD, chemical oxygen demand (COD, pH and alkalinity were determined according to Turkish Standard Methods. The determined averages values belong to wastewaters obtained from liming process were as following: pH 11.71; COD 16821 mg L-1; BOD 4357 mg L-1; TSS 39023 mg L-1; oil and grease 364 mg L-1; S-2 concentration 802 mg L-1; alkalinity 2115 mg L-1. The determined averages values belong to wastewaters obtained from chromium tanning process were also as following: pH 4.23; COD 6740 mg L-1; BOD 377 mg L-1; Cr+3 concentrations 372 mg L-1; Cr+6 concentrations 127 mg L-1; TSS 14553 mg L-1; oil and grease 343 mg L-1. The results of all analyzes were higher than wastewater discharge standards. As a result, it’s necessary to use more effective treatments in order to reduce the negative impacts of leather tanning industry that affect environment, natural water resources and at last human health and welfare.

Hydrodynamics and water quality models applied to Sepetiba Bay

Science.gov (United States)

Cunha, Cynara de L. da N.; Rosman, Paulo C. C.; Ferreira, Aldo Pacheco; Carlos do Nascimento Monteiro, Teófilo

2006-10-01

A coupled hydrodynamic and water quality model is used to simulate the pollution in Sepetiba Bay due to sewage effluent. Sepetiba Bay has a complicated geometry and bottom topography, and is located on the Brazilian coast near Rio de Janeiro. In the simulation, the dissolved oxygen (DO) concentration and biochemical oxygen demand (BOD) are used as indicators for the presence of organic matter in the body of water, and as parameters for evaluating the environmental pollution of the eastern part of Sepetiba Bay. Effluent sources in the model are taken from DO and BOD field measurements. The simulation results are consistent with field observations and demonstrate that the model has been correctly calibrated. The model is suitable for evaluating the environmental impact of sewage effluent on Sepetiba Bay from river inflows, assessing the feasibility of different treatment schemes, and developing specific monitoring activities. This approach has general applicability for environmental assessment of complicated coastal bays.

Impacts of a high-discharge submarine sewage outfall on water quality in the coastal zone of Salvador (Bahia, Brazil)

KAUST Repository

Roth, Florian; Lessa, G.C.; Wild, C.; Kikuchi, R.K.P.; Naumann, M.S.

2016-01-01

Carbon and nitrogen stable isotopic signatures of suspended particulate organic matter and seawater biological oxygen demand (BOD) were measured along a coastal transect during summer 2015 to investigate pollution impacts of a high-discharge submarine sewage outfall close to Salvador, Brazil. Impacts of untreated sewage discharge were evident at the outfall site by depleted δ13Corg and δ15N signatures and 4-fold increased BOD rates. Pollution effects of a sewage plume were detectable for more than 6 km downstream from the outfall site, as seasonal wind- and tide-driven shelf hydrodynamics facilitated its advective transport into near-shore waters. There, sewage pollution was detectable at recreational beaches by depleted stable isotope signatures and elevated BOD rates at high tides, suggesting high bacterial activity and increased infection risk by human pathogens. These findings indicate the urgent necessity for appropriate wastewater treatment in Salvador to achieve acceptable standards for released effluents and coastal zone water quality.

Impacts of a high-discharge submarine sewage outfall on water quality in the coastal zone of Salvador (Bahia, Brazil).

Science.gov (United States)

Roth, F; Lessa, G C; Wild, C; Kikuchi, R K P; Naumann, M S

2016-05-15

Carbon and nitrogen stable isotopic signatures of suspended particulate organic matter and seawater biological oxygen demand (BOD) were measured along a coastal transect during summer 2015 to investigate pollution impacts of a high-discharge submarine sewage outfall close to Salvador, Brazil. Impacts of untreated sewage discharge were evident at the outfall site by depleted δ(13)Corg and δ(15)N signatures and 4-fold increased BOD rates. Pollution effects of a sewage plume were detectable for more than 6km downstream from the outfall site, as seasonal wind- and tide-driven shelf hydrodynamics facilitated its advective transport into near-shore waters. There, sewage pollution was detectable at recreational beaches by depleted stable isotope signatures and elevated BOD rates at high tides, suggesting high bacterial activity and increased infection risk by human pathogens. These findings indicate the urgent necessity for appropriate wastewater treatment in Salvador to achieve acceptable standards for released effluents and coastal zone water quality. Copyright © 2016 Elsevier Ltd. All rights reserved.

Impacts of a high-discharge submarine sewage outfall on water quality in the coastal zone of Salvador (Bahia, Brazil)

KAUST Repository

Roth, Florian

2016-03-30

Carbon and nitrogen stable isotopic signatures of suspended particulate organic matter and seawater biological oxygen demand (BOD) were measured along a coastal transect during summer 2015 to investigate pollution impacts of a high-discharge submarine sewage outfall close to Salvador, Brazil. Impacts of untreated sewage discharge were evident at the outfall site by depleted δ13Corg and δ15N signatures and 4-fold increased BOD rates. Pollution effects of a sewage plume were detectable for more than 6 km downstream from the outfall site, as seasonal wind- and tide-driven shelf hydrodynamics facilitated its advective transport into near-shore waters. There, sewage pollution was detectable at recreational beaches by depleted stable isotope signatures and elevated BOD rates at high tides, suggesting high bacterial activity and increased infection risk by human pathogens. These findings indicate the urgent necessity for appropriate wastewater treatment in Salvador to achieve acceptable standards for released effluents and coastal zone water quality.

On-site treatment of a motorway service area wastewater using a package sequencing batch reactor (SBR).

Science.gov (United States)

Del Solar, J; Hudson, S; Stephenson, T

2005-01-01

A sequencing batch reactor (SBR) treating the effluent of a motorway service station in the south of England situated on a major tourist route was investigated. Wastewater from the kitchens, toilets and washrooms facilities was collected from the areas on each side of the motorway for treatment on-site. The SBR was designed for a population equivalent (p.e.) of 500, assuming an average flow of 100 m3/d, influent biochemical oxygen demand (BOD) of 300 mg/l, and influent suspended solids (SS) of 300 mg/l. Influent monitoring over 8 weeks revealed that the average flow was only 65 m3/d and the average influent BOD and SS were 480 mg/l and 473 mg/l respectively. This corresponded to a high sludge loading rate (F:M) of 0.42 d(-1) which accounted for poor performance. Therefore the cycle times were extended from 6 h to 7 h and effluent BOD improved from 79 to 27 mg/l.

Development of a Field Laundry Wastewater Recycling System

Science.gov (United States)

1986-04-01

its physical , chemical, and toxicological properties . Chemical interactions may also occur in laundry water that may result in additional compounds of...was used to prepare a diatomite slurry needed to precoat the septums in the diatomaceous earth filter. II 6 If Sx COLLECTION TANK (CT) Figure 3...biochemical oxygen demand (BOD) bottles were then taken. The samples were divided into fractions for replicate testing of chemical and physical

Quantum dots assisted photocatalysis for the chemiluminometric determination of chemical oxygen demand using a single interface flow system

Energy Technology Data Exchange (ETDEWEB)

Silvestre, Cristina I.C.; Frigerio, Christian [Requimte, Department of Chemistry, Faculty of Pharmacy, Porto University, Rua Anibal Cunha 164, 4099-030, Porto (Portugal); Santos, Joao L.M., E-mail: joaolms@ff.up.pt [Requimte, Department of Chemistry, Faculty of Pharmacy, Porto University, Rua Anibal Cunha 164, 4099-030, Porto (Portugal); Lima, Jose L.F.C. [Requimte, Department of Chemistry, Faculty of Pharmacy, Porto University, Rua Anibal Cunha 164, 4099-030, Porto (Portugal)

2011-08-12

Highlights: {yields} A novel flow method for the determination of chemical oxygen demand is proposed. {yields} CdTe nanocrystals are irradiated with UV light to generate strong oxidizing species. {yields} Reactive species promote a fast catalytic degradation of organic matter. {yields} Luminol is used as a chemiluminescence probe for indirect COD assessment. {yields} A single interface flow system was implemented to automate the assays. - Abstract: A novel flow method for the determination of chemical oxygen demand (COD) is proposed in this work. It relies on the combination of a fully automated single interface flow system, an on-line UV photocatalytic unit and quantum dot (QD) nanotechnology. The developed approach takes advantage of CdTe nanocrystals capacity to generate strong oxidizing species upon irradiation with UV light, which fostered a fast catalytic degradation of the organic compounds. Luminol was used as a chemiluminescence (CL) probe for indirect COD assessment, since it is easily oxidized by the QD generated species yielding a strong CL emission that is quenched in the presence of the organic matter. The proposed methodology allowed the determination of COD concentrations between 1 and 35 mg L{sup -1}, with good precision (R.S.D. < 1.1%, n = 3) and a sampling frequency of about 33 h{sup -1}. The procedure was applied to the determination of COD in wastewater certified reference materials and the obtained results showed an excellent agreement with the certified values.

Oxygen rocking aqueous batteries utilizing reversible topotactic oxygen insertion/extraction in iron-based perovskite oxides Ca1–xLaxFeO3−δ

Science.gov (United States)

Hibino, Mitsuhiro; Kimura, Takeshi; Suga, Yosuke; Kudo, Tetsuichi; Mizuno, Noritaka

2012-01-01

Developments of large-scale energy storages with not only low cost and high safety but also abundant metals are significantly demanded. While lithium ion batteries are the most successful method, they cannot satisfy all conditions. Here we show the principle of novel lithium-free secondary oxygen rocking aqueous batteries, in which oxygen shuttles between the cathode and anode composed of iron-based perovskite-related oxides Ca0.5La0.5FeOz (2.5 ≤ z ≤ 2.75 and 2.75 ≤ z ≤ 3.0). Compound Ca0.5La0.5FeOz can undergo two kinds of reduction and reoxidation of Fe4+/Fe3+ and Fe3+/Fe2+, that are accompanied by reversible and repeatable topotactic oxygen extraction and reinsertion during discharge and charge processes. PMID:22924108

Benthic Uptake Rate due to Hyporheic Exchange: The Effects of Streambed Morphology for Constant and Sinusoidally Varying Nutrient Loads

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Daniele Tonina

2015-01-01

Full Text Available Hyporheic exchange carries reactive solutes, which may include biological oxygen demand (BOD, dissolved oxygen (DO and reactive dissolved inorganic nitrogen (Nr, into the sediment, where biochemical reactions consume DO. Here, we study the impact of streambed morphology, stream-reactive solute loads and their diel oscillations on the DO benthic uptake rate (BUR due to hyporheic processes. Our model solves the hyporheic flow field and the solute transport equations analytically, within a Lagrangian framework, considering advection, longitudinal diffusion and reactions modeled as first order kinetics. The application of the model to DO field measurements over a gravel bar-pool sequence shows a good match with measured DO concentrations with an overall agreement of 58% and a kappa index of 0.46. We apply the model to investigate the effects of daily constant and sinusoidally time varying stream BOD, DO and Nr loads and of the morphodynamic parameters on BUR. Our modeling results show that BUR varies as a function of bedform size and of nutrient loads and that the hyporheic zone may consume up to 0.06% of the stream DO at the pool-riffle bedform scale. Daily oscillations of stream BOD and DO loads have small effects on BUR, but may have an important influence on local hyporheic processes and organisms’ distribution.

Ozonation of acid yellow 17 dye in a semi-batch bubble column

International Nuclear Information System (INIS)

Lackey, Laura W.; Mines, Richard O.; McCreanor, Philip T.

2006-01-01

A semi-batch bubble column was used to evaluate the effect of ozonation on the removal of acid yellow 17 dye from water. Results indicate that ozonation is very effective at removing acid yellow 17 dye from synthetic textile wastewater. The ozone consumed to apparent dye removal ratio ranged from 2 to 15,000 mg ozone per mg of dye decolorized and was dependent on both ozonation time and apparent dye concentration. The biodegradability of the dye wastewater was evaluated by monitoring changes in 5-day biochemical oxygen demand (BOD 5 ) with respect to chemical oxygen demand (COD). Results indicate that the wastewater biodegradability increased with an increase in ozonation time. Film theory was used to kinetically model the gas-liquid reactions occurring in the reactor. Modeling results indicated that during the first 10-15 min of ozonation, the system could be characterized by a fast, pseudo-first-order regime. With continued ozonation, system kinetics transitioned through a moderate then to a slow regime. Successful modeling of this period required use of a kinetic equation corresponding to a more inclusive condition. Model results are presented

Characterization of landfill leachates and studies on heavy metal removal.

Science.gov (United States)

Ceçen, F; Gürsoy, G

2000-10-01

This study covers a thorough characterisation of landfill leachates emerging from a sanitary landfill area. The landfill leachates were obtained in the acidic stage of landfill stabilisation. Their organic content was high as reflected by the high BOD5 (5 day biological oxygen demand) and COD (chemical oxygen demand) values. They were also highly polluted in terms of the parameters TKN (total Kjeldahl nitrogen), NH4-N, alkalinity, hardness and heavy metals. Nickel was present in these wastewaters at a significant concentration. With regard to the high heavy metal content of these wastewaters, several physicochemical removal alternatives for the heavy metals Cu, Pb, Zn, Ni, Cd, Cr, Mn and Fe were tested using coagulation, flocculation, precipitation, base addition and aeration. Additionally, COD removal and ammonia stripping were examined. Co-precipitation with either alum or iron salts did not usually lead to significantly higher heavy metal removal than lime alone. The major methods leading to an effective heavy metal removal were aeration and lime addition. Nickel and cadmium seemed to be strongly complexed and were not removed by any method. Also lead removal proved to be difficult. The results are also discussed in terms of compliance with standards.

Treatment of landfill leachate using an aerated, horizontal subsurface-flow constructed wetland.

Science.gov (United States)

Nivala, J; Hoos, M B; Cross, C; Wallace, S; Parkin, G

2007-07-15

A pilot-scale subsurface-flow constructed wetland was installed at the Jones County Municipal Landfill, near Anamosa, Iowa, in August 1999 to demonstrate the use of constructed wetlands as a viable low-cost treatment option for leachate generated at small landfills. The system was equipped with a patented wetland aeration process to aid in removal of organic matter and ammonia nitrogen. The high iron content of the leachate caused the aeration system to cease 2 years into operation. Upon the installation of a pretreatment chamber for iron removal and a new aeration system, treatment efficiencies dramatically improved. Seasonal performance with and without aeration is reported for 5-day biochemical oxygen demand (BOD(5)), chemical oxygen demand (COD), ammonia nitrogen (NH(4)-N), and nitrate nitrogen (NO(3)-N). Since winter air temperatures in Iowa can be very cold, a layer of mulch insulation was installed on top of the wetland bed to keep the system from freezing. When the insulation layer was properly maintained (either through sufficient litterfall or replenishing the mulch layer), the wetland sustained air temperatures of as low as -26 degrees C without freezing problems.

Waste water purification using new porous ceramics prepared by recycling waste glass and bamboo charcoal

Science.gov (United States)

Nishida, Tetsuaki; Morimoto, Akane; Yamamoto, Yoshito; Kubuki, Shiro

2017-12-01

New porous ceramics (PC) prepared by recycling waste glass bottle of soft drinks (80 mass%) and bamboo charcoal (20 mass%) without any binder was applied to the waste water purification under aeration at 25 °C. Artificial waste water (15 L) containing 10 mL of milk was examined by combining 15 mL of activated sludge and 750 g of PC. Biochemical oxygen demand (BOD) showed a marked decrease from 178 to 4.0 (±0.1) mg L-1 in 5 days and to 2.0 (±0.1) mg L-1 in 7 days, which was equal to the Environmental Standard for the river water (class A) in Japan. Similarly, chemical oxygen demand (COD) decreased from 158 to 3.6 (±0.1) mg L-1 in 5 days and to 2.2 (±0.1) mg L-1 in 9 days, which was less than the Environmental Standard for the Seawater (class B) in Japan: 3.0 mg L-1. These results prove the high water purification ability of the PC, which will be effectively utilized for the purification of drinking water, fish preserve water, fish farm water, etc.

Simultaneous sampling of tissue oxygenation and oxygen consumption in skeletal muscle.

Science.gov (United States)

Nugent, William H; Song, Bjorn K; Pittman, Roland N; Golub, Aleksander S

2016-05-01

Under physiologic conditions, microvascular oxygen delivery appears to be well matched to oxygen consumption in respiring tissues. We present a technique to measure interstitial oxygen tension (PISFO2) and oxygen consumption (VO2) under steady-state conditions, as well as during the transitions from rest to activity and back. Phosphorescence Quenching Microscopy (PQM) was employed with pneumatic compression cycling to achieve 1 to 10 Hz sampling rates of interstitial PO2 and simultaneous recurrent sampling of VO2 (3/min) in the exteriorized rat spinotrapezius muscle. The compression pressure was optimized to 120-130 mmHg without adverse effect on the tissue preparation. A cycle of 5s compression followed by 15s recovery yielded a resting VO2 of 0.98 ± 0.03 ml O2/100 cm(3)min while preserving microvascular oxygen delivery. The measurement system was then used to assess VO2 dependence on PISFO2 at rest and further tested under conditions of isometric muscle contraction to demonstrate a robust ability to monitor the on-kinetics of tissue respiration and the compensatory changes in PISFO2 during contraction and recovery. The temporal and spatial resolution of this approach is well suited to studies seeking to characterize microvascular oxygen supply and demand in thin tissues. Copyright © 2015 Elsevier Inc. All rights reserved.

Effect of flow rate and disc area increment on the efficiency of rotating biological contactor for treating greywater

International Nuclear Information System (INIS)

Pathan, A.A.

2015-01-01

The performance of greywater treatment through RBC (Rotating Biological Contactor) is related to many factors including rotational speed of disc, surface area of the media, thickness of biological film; quality and flow rate of influent. The plastic media provides surface for biological slime. The slime is rotated alternatively into the settled wastewater and then into atmosphere to provide aerobic conditions for the microorganisms. In this study the performance of RBC is investigated at different flow rates and disk areas of media by introducing additional discs on the shaft of RBC. Initially efficiency of the RBC was observed on six flow rates at the disc area of 9.78m/sup 2/. Furthermore optimized three flow rates were used to augment the disk area. The efficiency of RBC system was improved significantly at disk area of 11.76m/sup 2/ and flow rate of 20 L/h. Under these conditions the removal of BOD5 (Biochemical Oxygen Demand) COD (Chemical Oxygen Demand) and TSS (Total Suspended Solid) was observed 83, 57 and 90% respectively. (author)

Fenceline water quality monitoring of effluents from BARC establishment

International Nuclear Information System (INIS)

Prathibha, P.; Kothai, P.; Saradhi, I.V.; Pandit, G.G.; Puranik, V.D.

2007-01-01

Wastewater generated from various sources (industrial, residential, rain water runoff etc.,) is either discharged into water bodies or reused/recycled for various purposes. Continuous monitoring of the wastewater is necessary to check whether these effluents are meeting the stringent limits proposed for discharge into water bodies or recycled/reused. Monitoring of these effluents also helps in designing the wastewater treatment system required to meet the standards. In this paper, water quality monitoring carried out during each quarter of the year 2005 for the effluents discharged from different utilities of BARC into Trombay bay is presented. The results indicate that the Bio-chemical oxygen demand (BOD) and chemical oxygen demand (COD) are in the range of 7.9 to 38.9 mg/l and 29.4 to 78.9 mg/l respectively. The nitrates and sulphates are in the range of 0.5 to 7.2 mg/l and 7.8 to 52.3 mg/l respectively. The water quality data of the parameters analyzed are well within the limits stipulated by Central Pollution Control Board. (author)

Long-term oxygen therapy for COPD. Improving longevity and quality of life in hypoxemic patients.

Science.gov (United States)

Weg, J G; Haas, C F

1998-04-01

Long-term oxygen therapy can increase life expectancy in hypoxemic patients with COPD. Accurate identification of hypoxemia requires arterial blood gas measurements. Pulse oximetry can be used to measure trends in oxygenation, oxygen needs, and oxygen requirements during exercise and sleep. A detailed oxygen prescription indicates: (1) the oxygen dose (L/min), (2) the number of hours per day that oxygen therapy is required, (3) the dose required during exercise, (4) the oxygen supply system: concentrator, compressed gas cylinder, or liquid oxygen reservoir, and (5) the delivery device: nasal cannula, demand-flow device, reservoir cannula, or transtracheal oxygen catheter.

Characteristics of Leachate and Their Effect on Shallow Groundwater Quality (Case Study : TPA Cipayung, Depok)

Science.gov (United States)

Widiastuti, Atika; Hartono, Djoko M.; Moersidik, Setyo S.; Gusniani, Irma

2018-03-01

The problems arising from landfill activity is leaked leachate that is not absorbed well into leachate stabilization pond which furthermore contaminates shallow groundwater around landfill, include Cipayung landfill. The aims of this study is to determine the characteristics of leachate and their effect on shallow groundwater quality around landfill based on temperature, pH, Total Suspended Solids (TSS), Biological Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total Nitrogen (TN), Mercury (Hg), and fecal coliform. Data were analyzed based on leachate samples at influent point, effluent point, and 7 sampling points of residents’s well with distance variation every 100 meters within 300 meters radius having leachate stabilization pond as benchmark. According to the standard of Indonesia’s Ministry of Environment and Forestry law No. 59 of 2016, the results showed that leachate quality was still above the standard of BOD, COD, and Total Nitrogen parameters; 4178.0 mg/L, 70556.0 mg/L and 373.3 mg/L for influent point, and 3142.0 mg/L, 9055.2 mg/L, and 350 mg/L for the effluent point. Pollution Index of shallow groundwater is between lightly and moderately contaminated. This study showed that the further the distance between sampling point and leachate stabilization pond is, the lower the Polution Index is.

Oxygen demand for the stabilization of the organic fraction of municipal solid waste in passively aerated bioreactors

International Nuclear Information System (INIS)

Kasinski, Slawomir; Wojnowska-Baryla, Irena

2014-01-01

Highlights: • The use of an passively aerated reactor enables effective stabilization of OFMSW. • Convective air flow does not inhibit the aerobic stabilization of waste. • The use of an passively aerated reactor reduces the heat loss due to convection. • The volume of supplied air exceeds 1.7–2.88 times the microorganisms demand. - Abstract: Conventional aerobic waste treatment technologies require the use of aeration devices that actively transport air through the stabilized waste mass, which greatly increases operating costs. In addition, improperly operated active aeration systems, may have the adverse effect of cooling the stabilized biomass. Because active aeration can be a limiting factor for the stabilization process, passive aeration can be equally effective and less expensive. Unfortunately, there are few reports documenting the use of passive aeration systems in municipal waste stabilization. There have been doubts raised as to whether a passive aeration system provides enough oxygen to the organic matter mineralization processes. In this paper, the effectiveness of aeration during aerobic stabilization of four different organic fractions of municipal waste in a reactor with an integrated passive ventilation system and leachate recirculation was analyzed. For the study, four fractions separated by a rotary screen were chosen. Despite the high temperatures in the reactor, the air flow rate was below 0.016 m 3 /h. Using Darcy’s equation, theoretical values of the air flow rate were estimated, depending on the intensity of microbial metabolism and the amount of oxygen required for the oxidation of organic compounds. Calculations showed that the volume of supplied air exceeded the microorganisms demand for oxidation and endogenous activity by 1.7–2.88-fold

Avaliação in vitro da eficiência de inóculos no tratamento anaeróbio de efluentes líquidos de suinocultura Efficiency of seeding material in anaerobic treatment of swine liquid waste: an in vitro trial

Directory of Open Access Journals (Sweden)

L.S. Rodrigues

2004-10-01

Full Text Available Avaliou-se o efeito de inóculos (tratamentos na degradação dos dejetos líquidos de suínos, em diferentes tempos de detenção hidráulica (0, 30, 60, 90, 120, 150, 180 horas. Foram utilizados um inóculo comercial, na dose recomendada pelo fabricante, três inóculos alternativos à base de esterco bovino, cama de frango e esgoto doméstico, todos aplicados na dose de 5ml/l, e um tratamento-controle, sem inóculo. Foi utilizado o delineamento inteiramente ao acaso, em esquema de parcelas subdivididas, empregando-se três repetições. Após cada tempo de detenção foram realizadas as seguintes análises: pH, demanda bioquímica de oxigênio (DBO, demanda química de oxigênio, sólidos totais, sólidos totais voláteis e sólidos sedimentáveis, temperaturas do ar e do líquido. Os inóculos comercial e alternativo à base de cama de frango promoveram maior redução de DBO que os demais, 68,5% e 67,5%, respectivamente.The effect of seeding material (treatments upon degrading liquid waste of swine was evaluated at different hydraulic retention times (0, 30, 60, 90, 120, 150, 180 hours. A commercial seeding material according to the recommended manufacture dosage, three alternative seeding materials based on bovine manure, chicken manure, and domestic sewage, all of them applied at the dosage of 5ml/l, and a control treatment (without seeding material were used. An entirely randomized design was set to study the subdivided fragments using three repetitions. After each detention time, the following analyses have been performed: pH, biochemical oxygen demand (BOD, chemical oxygen demand, total solids, total volatile solid, settling solids, air and liquid temperatures. The commercial and alternative seeding materials based on chicken waste promoted a higher reduction of BOD than the other ones, 68.5% and 67.5%, respectively.

Tourism demand in Asean-5 countries: Evidence from panel data analysis

Directory of Open Access Journals (Sweden)

Nur Fadzlunnisaa Wakimin

2018-06-01

Full Text Available Tourism has emerged as a major industry worldwide and a sector in many countries. This sector has experienced a rapid growth and has become a key driver for sustainable socioeconomic developments globally. However, tourism is also a vector of environmental degradation through the emission of greenhouse gases (GHG. Therefore, the aim of this study was to analyze the main factors that are affecting the tourism demand in ASEAN-5 countries. Using a panel of five ASEAN countries over a 44-year period and applying the Pooled Mean Group (PMG approach, the empirical results have shown that the major determinants of tourism demand in these countries are income, trade, tourism price, and carbon dioxide emission. The results have also shown that the PMG performed better than the Mean Group (MG estimator. This paper refers to the PMG estimator because it constrains the long run coefficients to be identical, but allows the short run coefficients and error variances to differ across groups. Income and trade appeared to exert significant positive impacts on tourism demand, whereas tourism price and carbon dioxide emissions have negative impacts on tourism demand in these ASEAN-5 countries. The results would be a good reference for policy makers in these specific countries.

Effect of hypolimnetic oxygenation on oxygen depletion rates in two water-supply reservoirs.

Science.gov (United States)

Gantzer, Paul A; Bryant, Lee D; Little, John C

2009-04-01

Oxygenation systems, such as bubble-plume diffusers, are used to improve water quality by replenishing dissolved oxygen (DO) in the hypolimnia of water-supply reservoirs. The diffusers induce circulation and mixing, which helps distribute DO throughout the hypolimnion. Mixing, however, has also been observed to increase hypolimnetic oxygen demand (HOD) during system operation, thus accelerating oxygen depletion. Two water-supply reservoirs (Spring Hollow Reservoir (SHR) and Carvins Cove Reservoir (CCR)) that employ linear bubble-plume diffusers were studied to quantify diffuser effects on HOD. A recently validated plume model was used to predict oxygen addition rates. The results were used together with observed oxygen accumulation rates to evaluate HOD over a wide range of applied gas flow rates. Plume-induced mixing correlated well with applied gas flow rate and was observed to increase HOD. Linear relationships between applied gas flow rate and HOD were found for both SHR and CCR. HOD was also observed to be independent of bulk hypolimnion oxygen concentration, indicating that HOD is controlled by induced mixing. Despite transient increases in HOD, oxygenation caused an overall decrease in background HOD, as well as a decrease in induced HOD during diffuser operation, over several years. This suggests that the residual or background oxygen demand decreases from one year to the next. Despite diffuser-induced increases in HOD, hypolimnetic oxygenation remains a viable method for replenishing DO in thermally-stratified water-supply reservoirs such as SHR and CCR.

Research on the sewage treatment in high altitude region based on Lhasa Sewage Treatment Plant

Science.gov (United States)

Xu, Jin; Li, Shuwen

2017-12-01

Sewage treatment is of great significance to enhance environmental quality, consolidate pollution prevention and ecological protection, and ensure sustainable economic and social development in high altitude region. However, there are numerous difficulties in sewage treatment due to the alpine climate, the relatively low economic development level, and the backward operation and management styles, etc. In this study, the characteristics of influent quality in the sewage treatment plant in Lhasa are investigated by analysing the influent BOD5/COD and BOD5/TN, comparing key indexes recorded from 2014 to 2016 with the hinterland. Results show that the concentration of influent COD, BOD5, NH3-N and SS in the Lhasa sewage treatment plant, in which the sewage belongs to low-concentration urban sewage, is smaller than that in the domestic sewage treatment plants in the mainland. The concentration ratio of BOD5/COD and BOD5/TN is below 0.4 and 4, which indicates that the biodegradation is poor and the carbon sources are in bad demand. The consequences obtained play a vital role in the design, operation and management of sewage treatment plants in high altitude region.

Biochemical oxygen demand and nutrient processing in a novel multi-stage raw municipal wastewater and acid mine drainage passive co-treatment system.

Science.gov (United States)

Strosnider, W H; Winfrey, B K; Nairn, R W

2011-01-01

A laboratory-scale, four-stage continuous flow reactor system was constructed to test the viability of high-strength acid mine drainage (AMD) and municipal wastewater (MWW) passive co-treatment. The synthetic AMD had pH 2.60 and 1860 mg/L acidity as CaCO(3) equivalent with 46, 0.25, 2, 290, 55, 1.2 and 390 mg/L of Al, As, Cd, Fe, Mn, Pb and Zn, respectively. The AMD was introduced to the system at a 1:2 ratio with raw MWW from the City of Norman, Oklahoma USA containing 265 ± 94 mg/L BOD(5), 11.5 ± 5.3 mg/L PO(4)(-3), and 20.8 ± 1.8 mg/L NH(4)(+)-N. During the 135 d experiment, PO(4)(-3) and NH(4)(+)-N were decreased to treatment is a viable ecological engineering approach for the developed and developing world that can be optimized and applied to improve water quality with minimal use of fossil fuels and refined materials. Copyright © 2010 Elsevier Ltd. All rights reserved.

Oxygen supply in aquatic ectotherms: partial pressure and solubility together explain biodiversity and size patterns.

Science.gov (United States)

Verberk, Wilco C E P; Bilton, David T; Calosi, Piero; Spicer, John I

2011-08-01

Aquatic ectotherms face the continuous challenge of capturing sufficient oxygen from their environment as the diffusion rate of oxygen in water is 3 x 10(5) times lower than in air. Despite the recognized importance of oxygen in shaping aquatic communities, consensus on what drives environmental oxygen availability is lacking. Physiologists emphasize oxygen partial pressure, while ecologists emphasize oxygen solubility, traditionally expressing oxygen in terms of concentrations. To resolve the question of whether partial pressure or solubility limits oxygen supply in nature, we return to first principles and derive an index of oxygen supply from Fick's classic first law of diffusion. This oxygen supply index (OSI) incorporates both partial pressure and solubility. Our OSI successfully explains published patterns in body size and species across environmental clines linked to differences in oxygen partial pressure (altitude, organic pollution) or oxygen solubility (temperature and salinity). Moreover, the OSI was more accurately and consistently related to these ecological patterns than other measures of oxygen (oxygen saturation, dissolved oxygen concentration, biochemical oxygen demand concentrations) and similarly outperformed temperature and altitude, which covaried with these environmental clines. Intriguingly, by incorporating gas diffusion rates, it becomes clear that actually more oxygen is available to an organism in warmer habitats where lower oxygen concentrations would suggest the reverse. Under our model, the observed reductions in aerobic performance in warmer habitats do not arise from lower oxygen concentrations, but instead through organismal oxygen demand exceeding supply. This reappraisal of how organismal thermal physiology and oxygen demands together shape aerobic performance in aquatic ectotherms and the new insight of how these components change with temperature have broad implications for predicting the responses of aquatic communities to

Chemical Oxygen Demand abatement in sewage using Micro-Aeration Enhanced Ecological Floating Bed

Science.gov (United States)

Shi, Hongle; Zhou, Gaofeng; Liu, Yiqing; Tan, Jiancong; Fu, Yongsheng

2018-02-01

The traditional ecological floating bed combined with micro-aeration system and artificial medium was developed for the removal of contaminants and remediation of surface water. This micro-aeration enhanced ecological floating bed (MAEEFB) consisted of aeration unit, microbial processing unit and aquatic plant unit. Batch experiments were conducted in different operating conditions on the removal of chemical oxygen demand (COD) in the sewage using MAEEFB. The removal rate of COD by MAEEFB, enhanced ecological floating bed (EEFB) and traditional ecological floating bed (TEFB) in the same reaction conditions was 59.2%, 56.9% and 30.6%, respectively, indicating that the combination of micro-aeration system and artificial medium could enhance the removal efficiency of COD in TEFB. In MAEEFB, the aeration intensity should be designed reasonablely considering both treatment efficiency and operation cost. Only increasing the specific surface area of the packing cannot effectively improve the purification efficiency of water. Factors like packing material, ability of intercepting organics and complicated extent of microorganisms attaching on the packing should also be considered.

Domestic Wastewater Depuration Using a Horizontal Subsurface Flow Constructed Wetland and Theoretical Surface Optimization: A Case Study under Dry Mediterranean Climate

Directory of Open Access Journals (Sweden)

Pedro Andreo-Martínez

2016-10-01

Full Text Available The wastewater generated by isolated houses without access to public sewers can cause environmental problems, like the contamination of aquifers with nitrates and phosphates, as occurs in southeastern Spain. The effectiveness of a previously built horizontal subsurface flow constructed wetland (HF-CW was studied over two years as a possible solution. This HF-CW measured 27 m2; it was planted with Phragmites australis(Cav. Trin. Ex Steuds sp. Altissima and the parameters studied were those required by European Union (EU legislation and adopted by Spain. Average abatement efficiency rates, for the first and the second year of study, were: biochemical oxygen demand over five days (BOD5 (96.4%, 92.0%, chemical oxygen demand (COD (84.6%, 77.7%, total suspended solids(TSS (94.8%,89.9%,total nitrogen(TN(79.5%,66.0%,ammonium nitrogen(NH4+-N(98.8%, 86.6% and total phosphorous (TP (83.7%, 82.8%. Average abatement efficiency for nitrate nitrogen (NO3−-N (−1280.5%, −961.1% and nitrite nitrogen (NO2−-N (−5.8%, −40.0% were negative because its content in influent wastewater was very low and they appear mainly from influent NH4+-N, as a result of purification processes carried out in the HF-CW bed. The abatement rates make the system suitable to produce discharges into the environment in accordance with Spanish law. It is noteworthy that the HF-CW patch suffered an episode of bed drying during the summer of 2013, whereby the causes were related to system oversizing and high evapotranspiration in the area. As a consequence, the decrease in the abatement of water pollutants during the second year can be attributed to the creation of preferential water flow paths and short circuits through the constructed wetland (CW bed. As a result of the oversizing of the CW, a theoretical resizing based on BOD5, TSS, TN or TP is proposed. The calculated values for the redesign were: 5.22 m2 considering DBO5, 0.18 m2 considering TSS, 10.14 m2 considering

Investigation of Wastewater Pollution at Clan Jetty, Penang

Directory of Open Access Journals (Sweden)

Razak Fazilah Md

2014-01-01

Full Text Available This study aims to determine the level of wastewater pollution at Clan Jetty, Penang. 20 locations were chosen for water sampling around the jetties. Experiments were conducted to investigate the parameters, namely, temperature at each point, Chemical Oxygen Demand (COD, Biochemical Oxygen Demand (BOD, pH, Dissolved Oxygen (DO, the presence of Coliform and E. coli, Nitrate Nitrogen, Ammonical Nitrogen, Suspended Solids, Oil and Grease as well as Total Phosphorus (TP. Laboratory results showed that Point 1A was the most polluted location compared to other sampling points. The highest COD recording was 5824 mg/L at Point 1A and the lowest amount of 103 mg/L was recorded at Point 4. This study demonstrates that the absence of a sewerage system contributes to marine pollution around the jetties. Thus, a sewerage system is the best solution to improve water quality around the jetties in the future.

Optimization of Crude Oil and PAHs Degradation by Stenotrophomonas rhizophila KX082814 Strain through Response Surface Methodology Using Box-Behnken Design

Science.gov (United States)

Virupakshappa, Praveen Kumar Siddalingappa; Mishra, Gaurav; Mehkri, Mohammed Ameenuddin

2016-01-01

The present paper describes the process optimization study for crude oil degradation which is a continuation of our earlier work on hydrocarbon degradation study of the isolate Stenotrophomonas rhizophila (PM-1) with GenBank accession number KX082814. Response Surface Methodology with Box-Behnken Design was used to optimize the process wherein temperature, pH, salinity, and inoculum size (at three levels) were used as independent variables and Total Petroleum Hydrocarbon, Biological Oxygen Demand, and Chemical Oxygen Demand of crude oil and PAHs as dependent variables (response). The statistical analysis, via ANOVA, showed coefficient of determination R 2 as 0.7678 with statistically significant P value 0.0163 fitting in second-order quadratic regression model for crude oil removal. The predicted optimum parameters, namely, temperature, pH, salinity, and inoculum size, were found to be 32.5°C, 9, 12.5, and 12.5 mL, respectively. At this optimum condition, the observed and predicted PAHs and crude oil removal were found to be 71.82% and 79.53% in validation experiments, respectively. The % TPH results correlate with GC/MS studies, BOD, COD, and TPC. The validation of numerical optimization was done through GC/MS studies and % removal of crude oil. PMID:28116165

Oxygen requirements of the earliest animals

DEFF Research Database (Denmark)

Mills, Daniel Brady; Ward, Lewis M.; Jones, CarriAyne

2014-01-01

likely exhibited a physiology and morphology similar to that of a modern sponge, its oxygen demands may have been met well before the enhanced oxygenation of the Ediacaran Period. Therefore, the origin of animals may not have been triggered by a contemporaneous rise in the oxygen content...

Municipal wastewater characteristics in Thailand and effects of soft intervention measures in households on pollutant discharge reduction.

Science.gov (United States)

Tsuzuki, Y; Koottatep, T; Jiawkok, S; Saengpeng, S

2010-01-01

In developing countries with large Millennium Development Goals (MDGs) sanitation indicator, pollutant discharge reduction function of wastewater treatment systems should be considered. In this paper, pollutant generations per capita (PGCs) and pollutant discharges per capita (PDCs) are estimated as a base dataset for wastewater management in Thailand. PDCs of black water, i.e. toilet wastewater, are found to be much smaller than PGCs of black water. However, PDCs of gray water, i.e. municipal wastewater other than toilet wastewater are large. Gray water is often discharged without treatment and contributes much to ambient water deterioration. Moreover, possible 5-day biological oxygen demand (BOD5) discharge reductions with "soft interventions", i.e. measurements in households to reduce wastewater pollutant discharge such as using a paper filter or a plastic net in kitchen sinks and so on, are estimated as 39, 21 and 34% for BOD5, total Kjeldahl nitrogen (TKN) and phosphate (PO4-P), respectively. For the estimation, environmental accounting housekeeping (EAH) books of domestic wastewater, spreadsheets with pollutant discharges by water usages and possible effects of "soft interventions" are applied. The framework of this study with "soft intervention" effects on pollutant discharge reductions should enhance wastewater management especially in the areas under development of wastewater treatment systems.

Field study of the composition of greywater and comparison of microbiological indicators of water quality in on-site systems.

Science.gov (United States)

Leonard, Margaret; Gilpin, Brent; Robson, Beth; Wall, Katrina

2016-08-01

Thirty on-site greywater systems were sampled to determine greywater characteristics and practices in the field. Kitchen greywater was present at eight sites and urine was included at seven sites. These non-traditional sources resulted in significantly higher concentrations of enterococci and 5-day biochemical oxygen demand (BOD5) in greywater. Even with the removal of these sources, the concentrations of microbial indicators indicated high levels of contamination could occur across all greywater sources, including "light" greywater. Using multiple microbial indicators showed that all samples had the potential for faecal contamination. Bacteroidales markers were confirmed in treated greywater and in each greywater source, highlighting the potential for human faecal contamination. Although Escherichia coli was absent in treated greywater recycled to the house, other microbial indicators were present; hence, caution is required in using E. coli concentrations as the sole indicator of microbiological water quality. High BOD5 or total suspended solid concentrations exceeded the levels recommended for effective disinfection. Subsurface irrigation, which is assumed to provide a five-log reduction in exposure, is a suitable reuse option for non-disinfected greywater. Only half the occupants had a good understanding of their greywater systems and 25 % of systems were poorly maintained. Elevated microbial indicator contamination of greywater sludge is a potential hazard during maintenance.

Ultrafast atomic layer-by-layer oxygen vacancy-exchange diffusion in double-perovskite LnBaCo2O5.5+δ thin films.

Science.gov (United States)

Bao, Shanyong; Ma, Chunrui; Chen, Garry; Xu, Xing; Enriquez, Erik; Chen, Chonglin; Zhang, Yamei; Bettis, Jerry L; Whangbo, Myung-Hwan; Dong, Chuang; Zhang, Qingyu

2014-04-22

Surface exchange and oxygen vacancy diffusion dynamics were studied in double-perovskites LnBaCo2O5.5+δ (LnBCO) single-crystalline thin films (Ln = Er, Pr; -0.5 atoms in the LnBCO thin films is taking the layer by layer oxygen-vacancy-exchange mechanism. The first principles density functional theory calculations indicate that hydrogen atoms are present in LnBCO as bound to oxygen forming O-H bonds. This unprecedented oscillation phenomenon provides the first direct experimental evidence of the layer by layer oxygen vacancy exchange diffusion mechanism.

Oxygen therapy reduces postoperative tachycardia

DEFF Research Database (Denmark)

Stausholm, K; Kehlet, H; Rosenberg, J

1995-01-01

Concomitant hypoxaemia and tachycardia in the postoperative period is unfavourable for the myocardium. Since hypoxaemia per se may be involved in the pathogenesis of postoperative tachycardia, we have studied the effect of oxygen therapy on tachycardia in 12 patients randomly allocated to blinded...... air or oxygen by facemask on the second or third day after major surgery. Inclusion criteria were arterial hypoxaemia (oxygen saturation 90 beat.min-1). Each patient responded similarly to oxygen therapy: an increase in arterial oxygen saturation and a decrease...... in heart rate (p oxygen has a positive effect on the cardiac oxygen delivery and demand balance....

Characterization (environmental Signature) and Function of the Main Instrumented (monitoring Water Quality Network in Real Time) Rivers Atoyac and Zahuapan in High Atoyac Basin; in Dry, Rain and Winter Season 2013-2014; Puebla-Tlaxcala Mexico

Science.gov (United States)

Tavera, E. M.; Rodriguez-Espinosa, P. F.; Morales-Garcia, S. S.; Muñoz-Sevilla, N. P.

2014-12-01

The Zahuapan and Atoyac rivers were characterized in the Upper Atoyac through the integration of physical and chemical parameters (environmental firm) determining the behavior and function of the basin as a tool for measuring and monitoring the quality and management of water resources of the water in one of the most polluted rivers in Mexico. For the determination of the environmental signature proceeded to characterize the water through 11 physicochemical parameters: temperature (T), potential hydrogen (pH), dissolved oxygen (DO), spectral absorption coefficient (SAC), the reduction of oxide potential (ORP), turbidity (Turb), conductivity (l), biochemical oxygen demand in 5 days (BOD5), chemical oxygen demand (COD), total suspended solids (TSS) and total dissolved solids (TDS ), which were evaluated in 49 sites in the dry season, 47 for the rainy season and 23 for the winter season in the basin and Atoyac Zahuapan Alto Atoyac, Puebla-Tlaxcala, Mexico river; finding a mathematical algorithm to assimilate and better represent the information obtained. The algorithm allows us to estimate correlation greater than 0.85. The results allow us to propose the algorithm used in the monitoring stations for purposes of processing information assimilated form.This measurement and monitoring of water quality supports the project, the monitoring network in real time and the actions to clean up Atoyac River, in the urban area of the city of Puebla.

Impacts from oil and gas produced water discharges on the Gulf of Mexico hypoxic zone

International Nuclear Information System (INIS)

Parker, M.E.; Satterlee, K.; Veil, J.A.

2006-01-01

Shallow water areas of the Gulf of Mexico continental shelf experience low dissolved oxygen (hypoxia) each summer. The hypoxic zone is primarily caused by input of nutrients from the Mississippi and Atchafalaya Rivers. The nutrients stimulate the growth of phytoplankton, which leads to reduction of the oxygen concentration near the sea floor. During the renewal of an offshore discharge permit used by the oil and gas industry in the Gulf of Mexico, the U.S. Environmental Protection Agency (EPA) identified the need to assess the potential contribution from produced water discharges to the occurrence of hypoxia. The EPA permit required either that all platforms in the hypoxic zone submit produced water samples, or that industry perform a coordinated sampling program. This paper, based on a report submitted to EPA in August 2005 (1), describes the results of the joint industry sampling program and the use of those results to quantify the relative significance of produced water discharges in the context of other sources on the occurrence of hypoxia in the Gulf of Mexico. In the sampling program, 16 facilities were selected for multiple sampling - three times each at one month intervals-- and another 34 sites for onetime sampling. The goal of the sampling program was to quantify the sources and amount of oxygen demand associated with a variety of Gulf of Mexico produced waters. Data collected included direct oxygen demand measured by BOD5 (5-day biochemical oxygen demand) and TOC (total organic carbon) and indirect oxygen demand measured by nitrogen compounds (ammonia, nitrate, nitrate, and TKN (total Kjeldahl nitrogen)) and phosphorus (total phosphorus and orthophosphate). These data will serve as inputs to several available computer models currently in use for forecasting the occurrence of hypoxia in the Gulf of Mexico. The output of each model will be compared for consistency in their predictions and then a semi-quantitative estimate of the relative significance of

[Domiciliary oxygen therapy].

Science.gov (United States)

Abdel Kafi, S

2010-09-01

In Belgium, oxygen therapy is becoming more and more accessible. When oxygen is needed for short periods or for special indications as palliative care, an agreement between mutual insurance companies and pharmacists allows the practitioner the home installation of gazeous oxygen cylinder or of oxygen concentrator. When long term oxygen therapy (LTOT) is indicated for patients with respiratory insufficiency, the pneumologist must first ask the INAMI the authorization to install one of the following modalities: oxygen concentrator with or without demand oxygen delivery cylinder and liquid oxygen. The goal of LTOT is to increase survival and quality of life. The principal and well accepted indication for LTOT is severe hypoxemia. The beneficial effects of oxygen therapy limited at night or on exertion are controversial. In order to increase patient's autonomy, oxygen can be prescribed for ambulation, respecting prescription's rules. At each step of oxygen therapy implementing (indication, choice of the device and follow-up) the patient under oxygen may benefit from a joint approach between the general practitioner and the chest specialist.

Framework 'interstitial' oxygen in La10(GeO4)5-(GeO5)O2 apatite electrolyte

International Nuclear Information System (INIS)

Pramana, S.S.; White, T.J.

2007-01-01

Oxygen conduction at low temperatures in apatites make these materials potentially useful as electrolytes in solid-oxide fuel cells, but our understanding of the defect structures enabling ion migration is incomplete. While conduction along [001] channels is dominant, considerable inter-tunnel mobility has been recognized. Using neutron powder diffraction of stoichiometric 'La 10 (GeO 4 ) 6 O 3 ', it has been shown that this compound is more correctly described as an La 10 (GeO 4 ) 5- (GeO 5 )O 2 apatite, in which high concentrations of interstitial oxygen reside within the channel walls. It is suggested that these framework interstitial O atoms provide a reservoir of ions that can migrate into the conducting channels of apatite, via a mechanism of inter-tunnel oxygen diffusion that transiently converts GeO 4 tetrahedra to GeO 5 distorted trigonal bipyramids. This structural modification is consistent with known crystal chemistry and may occur generally in oxide apatites. (orig.)

Effect of circulation on wastewater treatment by Lemna gibba and Lemna minor (floating aquatic macrophytes).

Science.gov (United States)

Demirezen Yilmaz, Dilek; Akbulut, Hatice

2011-01-01

In this study, laboratory tests were performed in order to examine growth characteristics of floating aquatic macrophytes (Lemna gibba and Lemna minor) in the presence of wastewater with circulation. The results showed that circulation of the waste water enhanced the kinetics of the process, as compared to the control systems. However, prolonged application of high circulation level had a different effect. In the presence of circulation with aquatic plants, there was additional 85.3-88.2% for BODs and 59.6-66.8% for COD decreases in the water quality indicators. In this study, the effectiveness of L. gibba and L. minor with circulation addition for the removal of four heavy metals (Pb, Ni, Mn, and Cu) from waste water was also investigated. Results from analysis confirmed the accumulation of different metals within the plant and a corresponding decrease of metals in the waste water. At the end of the study of circulation, L. gibba provided the metal removal for Cu, Pb, Ni, and Mn in the waste water as the ratio of 57%, 60%, 60%, and 62%, respectively. In this context, the best results were obtained when the action of L. gibba and L. minor plants, was combined with that of circulation. It is shown that in the presence of L. gibba and L. minor plants that are supplemented with circulation, the national standards of biochemical oxygen demand (BOD5) 27-33 mgL(-1) and chemical oxygen demand (COD) 62-78 mgL(-1) for L. minor and L. gibba, respectively, were reached after treatment. The new results can be used for design calculations regarding expected removal of pollutants by aquatic floating plants.

Lipid production from tapioca wastewater by culture of Scenedesmus sp. with simultaneous BOD, COD and nitrogen removal

Science.gov (United States)

Romaidi; Hasanudin, Muhammad; Kholifah, Khusnul; Maulidiyah, Alik; Putro, Sapto P.; Kikuchi, Akira; Sakaguchi, Toshifumi

2018-05-01

The use of microalgae to produce biodiesel or possibly remove nutrients from industrial wastewater has gained important attention during recent years due to their photosynthetic rate and its versatile nature to grow in various wastewater systems. In this study, a microalgae, Scenedesmus sp., was cultured to enhance the lipid production and nutrients removal from tapioca wastewater sample. To assess lipid production, Scenedesmus sp. was cultured in different concentration of tapioca wastewater sample (from 0 to 100 %), and nutrient removal including BOD, COD, NH4, NO2, NO3 level by Scenedesmus sp. was assessed in 100% of tapioca wastewater culture. After 8 days of culture, it was found out that 50% of tapioca wastewater sample resulted in highest concentration of lipid content than that of the other concentrations. The level of environment indicator as nutrient removal such as BOD, COD, NH4, NO2, NO3 were also decreased up to 74%, 72%, 95%, 91%, and 91%, respectively. The pH condition changed from initial condition acidic (pH: 4) to neutral or basic condition (pH: 7-8) as recommended in wastewater treatment system. This research provided a novel approach and achieved efficient simultaneous lipid production and nutrients removal from tapioca wastewater sample by Scenedesmus’s culture system.

Fiscal 1998 achievement report on regional consortium research and development project. Venture business raising type regional consortium - small business creating base type (Research and development of wastewater treatment technology for high concentration substances at pickles industry); 1998 nendo konodo tsukemono kojo haisui shori gijutsu no kaihatsu kenkyu seika hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-03-01

A technology is developed which treats pickle maker's wastewater containing highly concentrated saline contaminants by resorting to a combination of bacilli and membrane treatment. A 9m{sup 3}/day capable experimental plant is built and experiments are conducted. In the basic research, it is found that the temperature best for bacilli is 30-45 degrees C. They multiply without difficulty until the target salinity of 3% is achieved and, in a culture test, they can multiply until salinity is as high as 8%. Among submerged membrane filtration methods, hollow fiber membrane microfiltration is the most suitable, with its pressure loss increase rate low and stable at a filtration flux of 0.33m{sup 3}/m{sup 2}/day. Tests are conducted at salinity levels up to 1.5% at the experimental plant, when no adverse effect is detected. A BOD (biological oxygen demand) removal rate of not lower than 99.9% is attained under the condition where BOD=15,000-20,000mg/L. In a study of cost performance in which two methods are applied to a real size plant, it is found that the newly developed method is superior to the conventional activated sludge method because its installation area is approximately 1/3, construction cost approximately 65%, and running cost approximately 60% of what the conventional method demands. (NEDO)

Ọmọ̀jọ́lá, Bodé. Yorùbá Music in the Twentieth Century: Identity, Agency and Performance Practice

OpenAIRE

Vallier, Gilles-Félix

2017-01-01

Ọmọ̀jọ́lá, Bodé. — Yorùbá Music in the Twentieth Century : Identity, Agency and Performance Practice. New York, University of Rochester Press ; Eastman, Rochester Studies in Ethnomusicology, 2012, 285 p., bibl., ill., CD. Yorùbá Music in the Twentieth Century de Bodé Ọmọ̀jọ́lá déconstruit efficacement la notion d'une culture musicale yorùbá singulière, découvrant à la place une tapisserie pittoresque de traditions socialement et esthétiquement diverses, lesquelles sont unies, dans bien des ...

Modelling soil dust aerosol in the Bodélé depression during the BoDEx campaign

OpenAIRE

Tegen , I.; Heinold , B.; Todd , M.; Helmert , J.; Washington , R.; Dubovik , O.

2006-01-01

International audience; We present regional model simulations of the dust emission events during the Bodélé Dust Experiment (BoDEx) that was carried out in February and March 2005 in Chad. A box model version of the dust emission model is used to test different input parameters for the emission model, and to compare the dust emissions computed with observed wind speeds to those calculated with wind speeds from the regional model simulation. While field observations indicate that dust producti...

Modelling soil dust aerosol in the Bodélé depression during the BoDEx campaign

OpenAIRE

R. Washington; J. Helmert; M. Todd; B. Heinold; I. Tegen; O. Dubovik

2006-01-01

We present regional model simulations of the dust emission events during the Bodélé Dust Experiment (BoDEx) that was carried out in February and March 2005 in Chad. A box model version of the dust emission model is used to test different input parameters for the emission model, and to compare the dust emissions computed with observed wind speeds to those calculated with wind speeds from the regional model simulation. While field observations indicate that dust production occurs via ...

The effect of different soil uses on the quality of spring water

Directory of Open Access Journals (Sweden)

Lilian Vilela Andrade Pinto

2012-09-01

Full Text Available Several factors are known to be responsible for the degradation of water quality in our Planet’s spring sources. The goal of this study was to evaluate the impact of different anthropogenic activities on physico-chemical and biological properties of five spring water located in Inconfidentes, Minas Gerais State, Brazil. Analytical results have demonstrated that water source protected by native vegetation had the highest quality in terms of color, turbidity, biological oxygen demand (BOD5, total phosphate, nitrate, dissolved oxygen (DO, fecal coliforms and thermo-tolerant coliforms. On the other hand, the water quality was negatively impacted by the lack of adequate agricultural practices, such as the use of chemical inputs, the nonexistence of fenced livestock grazing areas and residential sewage system which are considered to be indispensable practices to minimize the environmental impact of anthropogenic activities and to protect human health.

Phytoremediation of domestic wastewaters in free water surface constructed wetlands using Azolla pinnata.

Science.gov (United States)

Akinbile, Christopher O; Ogunrinde, Temitope A; Che Bt Man, Hasfalina; Aziz, Hamidi Abdul

2016-01-01

Two constructed wetlands, one with Azolla pinnata plant (CW1) and the other without (CW2) for treating domestic wastewaters were developed. Fifteen water parameters which include: Dissolved Oxygen (DO), Biochemical Oxygen Demand (BOD5), Chemical Oxygen Demand (COD), Total Suspended Solid (TSS), Total Phosphorus (TP), Total Nitrogen (TN), Ammoniacal Nitrogen (NH3N), Turbidity, pH, Electrical Conductivity (EC), Iron (Fe), Magnesium (Mg), Manganese (Mn), and heavy metals such as Lead (Pb) and Zinc (Zn) were analyzed using standard laboratory procedures. The experiments were conducted in two (dry and wet) seasons simultaneously. Results showed considerable reductions in all parameters and metals including Zn in CW1 compared with CW2 in the two seasons considered while Pb and Mn were not detected throughout the study. Zn concentration levels reduced significantly in both seasons just as removal efficiencies of 70.03% and 64.51% were recorded for CW1 while 35.17% and 33.45% were recorded for CW2 in both seasons. There were no significant differences in the removal efficiencies of Fe in both seasons as 99.55%, 59.09%, 88.89%, and 53.56% were recorded in CW1 and CW2 respectively. Azolla pinnata has proved effective in domestic wastewater phytoremediation studies.

An improved solution of first order kinetics for biochemical oxygen ...

African Journals Online (AJOL)

This paper evaluated selected Biochemical Oxygen Demand first order kinetics methods. Domesticinstitutional wastewaters were collected twice in a month for three months from the Obafemi Awolowo University, Ile-Ife waste stabilization ponds. Biochemical Oxygen Demand concentrations at different days were determined ...

Stochastic modeling for river pollution of Sungai Perlis

International Nuclear Information System (INIS)

Yunus, Nurul Izzaty Mohd.; Rahman, Haliza Abd.; Bahar, Arifah

2015-01-01

River pollution has been recognized as a contributor to a wide range of health problems and disorders in human. It can pose health dangers to humans who come into contact with it, either directly or indirectly. Therefore, it is most important to measure the concentration of Biochemical Oxygen Demand (BOD) as a water quality parameter since the parameter has long been the basic means for determining the degree of water pollution in rivers. In this study, BOD is used as a parameter to estimate the water quality at Sungai Perlis. It has been observed that Sungai Perlis is polluted due to lack of management and improper use of resources. Therefore, it is of importance to model the Sungai Perlis water quality in order to describe and predict the water quality systems. The BOD concentration secondary data set is used which was extracted from the Drainage and Irrigation Department Perlis State website. The first order differential equation from Streeter – Phelps model was utilized as a deterministic model. Then, the model was developed into a stochastic model. Results from this study shows that the stochastic model is more adequate to describe and predict the BOD concentration and the water quality systems in Sungai Perlis by having smaller value of mean squared error (MSE)

Stochastic modeling for river pollution of Sungai Perlis

Energy Technology Data Exchange (ETDEWEB)

Yunus, Nurul Izzaty Mohd.; Rahman, Haliza Abd. [Department of Mathematical Sciences, Faculty of Science, Universiti Teknologi Malaysia,81310 Johor Bahru, Johor (Malaysia); Bahar, Arifah [UTM-Centre of Industrial and Applied Mathematics (UTM-CIAM) Universiti Teknologi Malaysia, 81310 Johor Bahru, Johor (Malaysia)

2015-02-03

River pollution has been recognized as a contributor to a wide range of health problems and disorders in human. It can pose health dangers to humans who come into contact with it, either directly or indirectly. Therefore, it is most important to measure the concentration of Biochemical Oxygen Demand (BOD) as a water quality parameter since the parameter has long been the basic means for determining the degree of water pollution in rivers. In this study, BOD is used as a parameter to estimate the water quality at Sungai Perlis. It has been observed that Sungai Perlis is polluted due to lack of management and improper use of resources. Therefore, it is of importance to model the Sungai Perlis water quality in order to describe and predict the water quality systems. The BOD concentration secondary data set is used which was extracted from the Drainage and Irrigation Department Perlis State website. The first order differential equation from Streeter – Phelps model was utilized as a deterministic model. Then, the model was developed into a stochastic model. Results from this study shows that the stochastic model is more adequate to describe and predict the BOD concentration and the water quality systems in Sungai Perlis by having smaller value of mean squared error (MSE)

Quality improvement in determination of chemical oxygen demand in samples considered difficult to analyze, through participation in proficiency-testing schemes

DEFF Research Database (Denmark)

Raposo, Francisco; Fernández-Cegrí, V.; De la Rubia, M.A.

2010-01-01

Chemical oxygen demand (COD) is a critical analytical parameter in waste and wastewater treatment, more specifically in anaerobic digestion, although little is known about the quality of measuring COD of anaerobic digestion samples. Proficiency testing (PT) is a powerful tool that can be used...... to test the performance achievable in the participants laboratories, so we carried out a second PT of COD determination in samples considered ‘‘difficult’’ to analyze (i.e. solid samples and liquid samples with high concentrations of suspended solids). The results obtained (based on acceptable z...

Pulmonary tolerance in man to continuous oxygen exposure at 3.0, 2.5, 2.0, and 1.5 ATA in Predictive Studies V

Science.gov (United States)

Clark, J. M.; Gelfand, R.; Flores, N. D.; Lambertsen, C. J.; Pisarello, J. B.

1987-01-01

Oxygen effects on pulmonary function were measured in normal, resting men who breathed oxygen continuously at 3.0, 2.5, 2.0, and 1.5 ATA to predefined limits of CNS, cardiac, or pulmonary tolerance. Rates of pulmonary symptom intensification and decrease in vital capacity (VC) increased progressively with elevation of inspired oxygen pressure. Although VC decrements occurred concurrently with symptoms, the lung volume changes became prominent when symptoms were still mild. The observed effects were consistent with the interpretation that small airway function is impaired more selectively by oxygen exposure at 3.0 and 2.5 ATA than by exposure at 2.0 and 1.5 ATA. Despite similar VC changes after oxygen exposure at 2.0 ATA for nearly 10 hr and exposure at 1.5 ATA for almost 18 hr, the 2.0 ATA exposure caused greater impairment of pulmonary function and required a longer recovery period.

Oxygen-enhanced MRI of the lungs. Intraindividual comparison between 1.5 and 3 Tesla

International Nuclear Information System (INIS)

Dietrich, Olaf; Thieme, S.F.; Maxien, D.; Nikolaou, K.; Reiser, M.; Schoenberg, S.O.; Fink, C.

2011-01-01

Purpose: To assess the feasibility of oxygen-enhanced MRI of the lung at 3 Tesla and to compare signal characteristics with 1.5 Tesla. Materials and Methods: 13 volunteers underwent oxygen-enhanced lung MRI at 1.5 and 3 T with a T 1-weighted single-slice non-selective inversion-recovery single-shot half-Fourier fast-spin-echo sequence with simultaneous respiratory and cardiac triggering in coronal orientation. 40 measurements were acquired during room air breathing and subsequently during oxygen breathing (15 L/min, close-fitting face-mask). The signal-to-noise ratio (SNR) of the lung tissue was determined with a difference image method. The image quality of all acquisitions was visually assessed. The mean values of the oxygen-induced relative signal enhancement and its regional coefficient of variation were calculated and the signal enhancement was displayed as color-coded parameter maps. Oxygen-enhancement maps were visually assessed with respect to the distribution and heterogeneity of the oxygen-related signal enhancement at both field strengths. Results: The mean relative signal enhancement due to oxygen breathing was 13 % (± 5.6 %) at 1.5 T and of 9.0 % (± 8.0 %) at 3 T. The regional coefficient of variation was significantly higher at 3 T. Visual and quantitative assessment of the enhancement maps showed considerably less homogeneous distribution of the signal enhancement at 3 T. The SNR was not significantly different but showed a trend to slightly higher values (increase of about 10 %) at 3 T. Conclusion: Oxygen-enhanced pulmonary MRI is feasible at 3 Tesla. However, signal enhancement is currently more heterogeneous and slightly lower at 3 T. (orig.)

Phytoremediation Potential of Duckweed (Lemna minor L.) On Steel Wastewater.

Science.gov (United States)

Saha, Priyanka; Banerjee, Angela; Sarkar, Supriya

2015-01-01

An eco-friendly and cost effective technique- phytoremediation was used to remediate contaminants from waste water. This study demonstrated that phytoremediation ability of duckweed (Lemna minor L.) to remove chloride, sulphate from Biological Oxygen Treatment (BOT) waste water of coke oven plant. The BOT water quality was assessed by analyzing physico-biochemical characters--pH, Biological oxygen demand (BOD), Chemical oxygen demand (COD), total dissolved solids (TDS) and elemental concentration. It was observed that an increase in pH value indicated an improvement of water quality. The experimental results showed that, duckweed effectively removed 30% chloride, 16% sulphate and 14% TDS from BOT waste water, which suggested its ability in phytoremediation for removal of chloride and sulphate from BOT waste water. A maximum increase of 30% relative growth rate of duckweed was achieved after 21 days of experiment. Thus, it was concluded that duckweed, an aquatic plant, can be considered for treatment of the effluent discharged from the coke oven plant.

Environmental Parameters Affecting the Algal Diversity in a Sewage Water Treatment Plant

International Nuclear Information System (INIS)

Hammad, D.M.; Tawfik, T.A.; Ismail, G.A.; Abou El-Khair, W.S.; Abou El-Nour, F.

2008-01-01

The present investigation was carried out at a tertiary sewage water treatment plant located at El-Kattameya city, Cairo, Egypt, for a duration period of 12 months during 2004. The present work aimed to study the algal diversity (phyto benthos and phytoplankton) of the different tanks (collector, oxidation, settling and effluent) included in the tertiary sewage treatment system with respect to changes in physico-chemical characteristics of sewage water during the different seasons to be used for golf course irrigation. The treatment system is of the physico-biological type. Representing data of the physico-chemical parameters are air and water temperatures, ph, electrical conductivity (EC), dissolved oxygen (DO), chemical oxygen demand (COD), biological oxygen demand (BOD), total suspended salts (TSS), total alkalinity, nutrients (nitrate, ammonia, phosphate, ortho-phosphorus, phosphorus and silicate), as well as major ions (calcium, potassium, sodium, magnesium, sulfate and chloride). In addition, the treatment efficiency of the system was evaluated and the suitability of using the effluent in irrigation purposes was discussed

Oxygen nitrogen and ozone: application in wastewater treatment and environment protection

Energy Technology Data Exchange (ETDEWEB)

Pinto, Julio A.G. [Oxigenio do Brasil, Sao Paulo, SP (Brazil)

1994-12-31

Oxygen`s versatility as an oxidant and as a combustion atmosphere provides clean solutions to different industries. Oxygen also finds excellent application for the regeneration of eutrophic surface waters where high biochemical oxygen demand loading demands extra available oxygen for life support. When even stronger oxidizing properties are needed, ozone may act as a supplement. Nitrogen, on the other hand, has excellent cooling capacity, resulting in practical application in solvent recapture, enabling processes to meet emission standards while allowing solvent recycle for reuse. 7 figs., 1 tab.

Oxygen nitrogen and ozone: application in wastewater treatment and environment protection

Energy Technology Data Exchange (ETDEWEB)

Pinto, Julio A.G. [Oxigenio do Brasil, Sao Paulo, SP (Brazil)

1993-12-31

Oxygen`s versatility as an oxidant and as a combustion atmosphere provides clean solutions to different industries. Oxygen also finds excellent application for the regeneration of eutrophic surface waters where high biochemical oxygen demand loading demands extra available oxygen for life support. When even stronger oxidizing properties are needed, ozone may act as a supplement. Nitrogen, on the other hand, has excellent cooling capacity, resulting in practical application in solvent recapture, enabling processes to meet emission standards while allowing solvent recycle for reuse. 7 figs., 1 tab.

Modelling soil dust aerosol in the Bodélé depression during the BoDEx campaign

OpenAIRE

I. Tegen; B. Heinold; M. Todd; J. Helmert; R. Washington; O. Dubovik; O. Dubovik

2006-01-01

We present regional model simulations of the dust emission events during the Bodélé Dust Experiment (BoDEx) that was carried out in February and March 2005 in Chad. A box model version of the dust emission model is used to test different input parameters for the emission model, and to compare the dust emissions computed with observed wind speeds to those calculated with wind speeds from the regional model simulation. While field observations indicate that dust production occurs via self-abras...

Using full-scale duckweed ponds as the finish stage for swine waste treatment with a focus on organic matter degradation.

Science.gov (United States)

Mohedano, R A; Costa, R H R; Hofmann, S M; Belli Filho, P

2014-01-01

The rapid increase in the number of swine has caused pronounced environmental impacts worldwide, especially on water resources. As an aggregate, smallholdings have an important role in South American pork production, contributing to the net diffusion of pollution. Thus, duckweed ponds have been successfully used for swine waste polishing, mainly for nutrient removal. Few studies have been carried out to assess organic matter degradation in duckweed ponds. Hence, the present study evaluated the efficiency of two full-scale duckweed ponds for organic matter reduction of swine waste on small pig farms. Duckweed ponds, in series, received the effluent after an anaerobic biodigester and storage pond, with a flow rate of 1 m(3) day(-1). After 1 year of monitoring, an improvement in effluent quality was observed, with a reduction in biochemical oxygen demand (BOD) and total chemical oxygen demand (tCOD), respectively, of 94.8 and 96.7%, operating at a loading rate of approximately 27 kgBOD ha(-1) day(-1) and 131 kgCOD ha(-1) day(-1). Algae inhibition due to duckweed coverage was strongly observed in the pond effluent, where chlorophyll a and turbidity remained below 25 μg L(-1) and 10 NTU. Using the study conditions described herein, duckweed ponds were shown to be a suitable technology for swine waste treatment, contributing to the environmental sustainability of rural areas.

Simulation of Constructed Wetland in treating Wastewater using Fuzzy Logic Technique

Science.gov (United States)

Sudarsan, J. S.; Subramani, Sheekha; Rajan, Rajitha J.; Shah, Isha; Nithiyanantham, S.

2018-04-01

Constructed wetlands act as a natural alternative to conventional methods of wastewater treatment. CW are found effective in wastewater containing inorganic matter, organic matter, toxic compounds, metals, nitrogen, phosphorous, heavy metals, organic chemicals, and pathogens. The treatment efficiency by the adaptation of CWs in treatment process is achieved by a complex interaction between plants, microorganisms, soil matrix and substances in the wastewater. Constructed wetland treatment systems are engineered systems designed in such a manner that it could take advantages of those processes occurring in natural wetlands in treating the wastewater concerned, but in a more controlled environment. Petrochemical wastewater was the type of wastewater taken for the study. Characteristics of petrochemical wastewater mainly oil, Biological Oxygen Demand (BOD) and Chemical oxygen demand (COD) were selected for treatment in constructed wetland as they are predominant in petrochemical wastewater. The conventional methods followed in the treatment are chemical and biological treatment. In this study, a fuzzy model for water quality assessment has been developed and water quality index value was obtained. The experiment conducted and further analysis using fuzzy logic indicated that interpretation of certain imprecise data can be improved within fuzzy inference system (FIS). Based on the analysis, we could observe that Typha sp contained wetland cell showed greater efficiency in removal of parameters such as COD and BOD than Phragmites sp. wetland cell.

A determination of the oxygen non-stoichiometry of the oxygen storage materials LnBaMn{sub 2}O{sub 5+δ} (Ln=Gd, Pr)

Energy Technology Data Exchange (ETDEWEB)

Jeamjumnunja, Kannika; Gong, Wenquan; Makarenko, Tatyana; Jacobson, Allan J., E-mail: ajjacob@uh.edu

2016-07-15

The A-site ordered double-perovskite oxides, LnBaMn{sub 2}O{sub 5+δ} (Ln=Gd, Pr), were synthesized and investigated to understand the effect of A site cation substitution on the oxygen storage properties of these materials. The present results are compared with our previous data for YBaMn{sub 2}O{sub 5+δ}. The results clearly reveal that changing the Ln cation strongly influences the oxidation/reduction behavior of LnBaMn{sub 2}O{sub 5+δ}. Based on thermogravimetric analysis data, oxygen uptake begins at lower temperatures in both air and oxygen in compounds with Ln{sup 3+} ions larger than Y{sup 3+}. These oxides exhibit almost complete and reversible oxygen uptake/release between fully-reduced LnBaMn{sub 2}O{sub 5} and fully-oxidized LnBaMn{sub 2}O{sub 6} during changes of the oxygen partial pressure between air and 1.99% H{sub 2}/Ar. In addition, the oxygen non-stoichiometries of GdBaMn{sub 2}O{sub 5+δ} and PrBaMn{sub 2}O{sub 5+δ} were determined as a function of pO{sub 2} at 600, 650, 700 and 750 °C by Coulometric titration at near-equilibrium conditions. The results confirm that these materials have two distinct phases on oxidation/reduction with δ≈0, 0.5 and a third phase with a range of composition with an oxygen content (5+δ) approaching ~6. The stabilities of the LnBaMn{sub 2}O{sub 5+δ} phases extend over a wide range of oxygen partial pressures (∼10{sup −25}≤pO{sub 2} (atm)≤∼1) depending on temperature. Isothermal experiments show that the larger the Ln{sup 3+} cation the lower pO{sub 2} for phase conversion. At some temperatures and pO{sub 2} conditions, the LnBaMn{sub 2}O{sub 5+δ} compounds are unstable with respect to decomposition to BaMnO{sub 3−δ} and LnMnO{sub 3}. This instability is more apparent in Coulometric titration experiments than in thermogravimetric analysis. The Coulometric titration experiments are necessarily slow in order to achieve equilibrium oxygen compositions. - Graphical abstract: Structure of Ln

Characterization of dissolved organic matter during landfill leachate treatment by sequencing batch reactor, aeration corrosive cell-Fenton, and granular activated carbon in series

International Nuclear Information System (INIS)

Bu Lin; Wang Kun; Zhao Qingliang; Wei Liangliang; Zhang Jing; Yang Junchen

2010-01-01

Landfill leachate is generally characterized as a complex recalcitrant wastewater containing high concentration of dissolved organic matter (DOM). A combination of sequencing batch reactor (SBR) + aeration corrosive cell-Fenton (ACF) + granular activated carbon (GAC) adsorption in series was proposed for the purpose of removing pollutants in the leachate. Fractionation was also performed to investigate the composition changes and characteristics of the leachate DOM in each treatment process. Experimental results showed that organic matter, in terms of chemical oxygen demand (COD), 5-day biological oxygen demand (BOD 5 ), and dissolved organic carbon (DOC), was reduced by 97.2%, 99.1%, and 98.7%, respectively. To differentiate the DOM portions, leachates were separated into five fractions by XAD-8 and XAD-4 resins: hydrophobic acid (HPO-A), hydrophobic neutral (HPO-N), transphilic acid (TPI-A), transphilic neutral (TPI-N), and hydrophilic fraction (HPI). The predominant fraction in the raw leachate was HPO-A (36% of DOC), while the dominant fraction in the final effluent was HPI (53% of DOC). Accordingly, macromolecules were degraded to simpler ones in a relatively narrow range below 1000 Da. Spectral and chromatographic analyses also showed that most humic-like substances in all fractions were effectively removed during the treatments and led to a simultaneous decrease in aromaticity.

Characterization of dissolved organic matter during landfill leachate treatment by sequencing batch reactor, aeration corrosive cell-Fenton, and granular activated carbon in series

Energy Technology Data Exchange (ETDEWEB)

Bu Lin [School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090 (China); Wang Kun [State Key Laboratory of Urban Water Resources and Environment (SKLUWRE), Harbin Institute of Technology, Harbin 150090 (China); School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090 (China); Zhao Qingliang, E-mail: zhql1962@yahoo.com.cn [State Key Laboratory of Urban Water Resources and Environment (SKLUWRE), Harbin Institute of Technology, Harbin 150090 (China); School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090 (China); Wei Liangliang; Zhang Jing; Yang Junchen [School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090 (China)

2010-07-15

Landfill leachate is generally characterized as a complex recalcitrant wastewater containing high concentration of dissolved organic matter (DOM). A combination of sequencing batch reactor (SBR) + aeration corrosive cell-Fenton (ACF) + granular activated carbon (GAC) adsorption in series was proposed for the purpose of removing pollutants in the leachate. Fractionation was also performed to investigate the composition changes and characteristics of the leachate DOM in each treatment process. Experimental results showed that organic matter, in terms of chemical oxygen demand (COD), 5-day biological oxygen demand (BOD{sub 5}), and dissolved organic carbon (DOC), was reduced by 97.2%, 99.1%, and 98.7%, respectively. To differentiate the DOM portions, leachates were separated into five fractions by XAD-8 and XAD-4 resins: hydrophobic acid (HPO-A), hydrophobic neutral (HPO-N), transphilic acid (TPI-A), transphilic neutral (TPI-N), and hydrophilic fraction (HPI). The predominant fraction in the raw leachate was HPO-A (36% of DOC), while the dominant fraction in the final effluent was HPI (53% of DOC). Accordingly, macromolecules were degraded to simpler ones in a relatively narrow range below 1000 Da. Spectral and chromatographic analyses also showed that most humic-like substances in all fractions were effectively removed during the treatments and led to a simultaneous decrease in aromaticity.

Hydraulic Behavior and Chemical Characterization of Lapilli as Material for Natural Filtering of Slurry

Directory of Open Access Journals (Sweden)

Nereida Falcón-Cardona

2015-06-01

Full Text Available Livestock effluents are a beneficial nutrient supply for crops, whereby their use is critical to ensure the sustainability of the farms global management. However, they can cause serious ecological problems if misused, polluting soils and groundwater. Combining “soft technology” and local materials is a low cost solution in terms of finance and energy. The REAGUA project (REuso AGUA, Water reuse in Spanish analyzes the possibility of using “picon” (lapilli as a material for the treatment of liquid manure from ruminants, for later use in subsurface drip irrigation system to produce forage and biofuels, in which the soil acts as a subsequent advanced treatment. A three-phase system, in which the effluent was poured with a vertical subsurface flow in an unsaturated medium, is designed. In order to determine the management conditions that optimize the filter, it was necessary to characterize the hydraulic behavior of lapilli and its ability to remove substances. Using three lapilli-filled columns, unsaturated flux, and a ruminant effluent, the reduction of chemical oxygen demand (COD, biochemical oxygen demand after 5 days (BOD5 and ammonia, phosphorus and suspension solids (SS obtained was over 80%, 90%, and 95% respectively, assumable values for irrigation.

Klang River water quality modelling using music

Science.gov (United States)

Zahari, Nazirul Mubin; Zawawi, Mohd Hafiz; Muda, Zakaria Che; Sidek, Lariyah Mohd; Fauzi, Nurfazila Mohd; Othman, Mohd Edzham Fareez; Ahmad, Zulkepply

2017-09-01

Water is an essential resource that sustains life on earth; changes in the natural quality and distribution of water have ecological impacts that can sometimes be devastating. Recently, Malaysia is facing many environmental issues regarding water pollution. The main causes of river pollution are rapid urbanization, arising from the development of residential, commercial, industrial sites, infrastructural facilities and others. The purpose of the study was to predict the water quality of the Connaught Bridge Power Station (CBPS), Klang River. Besides that, affects to the low tide and high tide and. to forecast the pollutant concentrations of the Biochemical Oxygen Demand (BOD) and Total Suspended Solid (TSS) for existing land use of the catchment area through water quality modeling (by using the MUSIC software). Besides that, to identifying an integrated urban stormwater treatment system (Best Management Practice or BMPs) to achieve optimal performance in improving the water quality of the catchment using the MUSIC software in catchment areas having tropical climates. Result from MUSIC Model such as BOD5 at station 1 can be reduce the concentration from Class IV to become Class III. Whereas, for TSS concentration from Class III to become Class II at the station 1. The model predicted a mean TSS reduction of 0.17%, TP reduction of 0.14%, TN reduction of 0.48% and BOD5 reduction of 0.31% for Station 1 Thus, from the result after purposed BMPs the water quality is safe to use because basically water quality monitoring is important due to threat such as activities are harmful to aquatic organisms and public health.

San Joaquin River Up-Stream DO TMDL Project Task 4: MonitoringStudy Interim Task Report #3

Energy Technology Data Exchange (ETDEWEB)

Stringfellow, William; Borglin, Sharon; Dahlgren, Randy; Hanlon,Jeremy; Graham, Justin; Burks, Remie; Hutchinson, Kathleen

2007-03-30

The purpose of the Dissolved Oxygen Total Maximum Daily LoadProject (DO TMDLProject) is to provide a comprehensive understanding ofthe sources and fate of oxygen consuming materials in the San JoaquinRiver (SJR) watershed between Channel Point and Lander Avenue (upstreamSJR). When completed, this study will provide the stakeholders anunderstanding of the baseline conditions of the basin, provide input foran allocation decision, and provide the stakeholders with a tool formeasuring the impact of any waterquality management program that may beimplemented as part of the DO TMDL process. Previous studies haveidentified algal biomass as the most significant oxygen-demandingsubstance in the DO TMDL Project study-area between of Channel Point andLander Ave onthe SJR. Other oxygen-demanding substances found in theupstream SJR include ammonia and organic carbon from sources other thanalgae. The DO TMDL Project study-area contains municipalities, dairies,wetlands, cattle ranching, irrigated agriculture, and industries thatcould potentially contribute biochemical oxygen demand (BOD) to the SJR.This study is designed to discriminate between algal BOD and othersources of BOD throughout the entire upstream SJR watershed. Algalbiomass is not a conserved substance, but grows and decays in the SJR;hence, characterization of oxygen-demanding substances in the SJR isinherently complicated and requires an integrated effort of extensivemonitoring, scientific study, and modeling. In order to achieve projectobjectives, project activities were divided into a number of Tasks withspecific goals and objectives. In this report, we present the results ofmonitoring and research conducted under Task 4 of the DO TMDL Project.The major objective of Task 4 is to collect sufficient hydrologic (flow)and water quality (WQ) data to characterize the loading of algae, otheroxygen-demanding materials, and nutrients fromindividual tributaries andsub-watersheds of the upstream SJR between Mossdale and

Nitrite oxidizing bacteria for water treatment in coastal aquaculture system

Science.gov (United States)

Noorak, S.; Rakkhiaw, S.; Limjirakhajornt, K.; Uppabullung, A.; Keawtawee, T.; Sangnoi, Y.

2018-04-01

This research aimed to isolate and characterize nitrite oxidizing bacteria and to study their capability for water quality improvement. Fourteen strains of bacteria with nitrite-oxidizing character were isolated after 21 days of enrichment in Pep-Beef-NOB medium contained NaNO2. Two strains, SF-1 and SF-5, showed highest nitrite removal rate for 42.42% and 37.2%, respectively. These strains were determined an efficiency of open-system wastewater treatment for 14 days. The results showed that control, SF-1 and SF-5 had remove ammonia from day 1 to day 6. At the end of the study, ammonia was removed by the control, SF-1 and SF-5 for 81.27%, 70.1% and 69.82%, respectively. Nitrite concentration was lowest at day 8 with removal rate of 98.73%, 98.3% and 97.24% from control, SF-1 and SF-5, respectively. However, nitrite concentration in control experiment was increased again at day 11 whereas in SF-1 and SF-5 were increased at day 13. Chemical Oxygen Demand (COD) was decreased by 77.78%, 73.50% and 78.63% in the control, SF-1 and SF-5, respectively. Biological Oxygen Demand (BOD) in the control, SF-1 and SF-5 were reduced by 85.92%, 79.53% and 82.09%, respectively. Based on 16S rRNA gene, SF-1 and SF-5 were identified as Bacillus vietnamensis and B. firmus, respectively.

Linear and nonlinear relationships between biodegradation potential and molecular descriptors/fragments for organic pollutants and a theoretical interpretation

International Nuclear Information System (INIS)

He, Jia; Qin, Weichao; Zhang, Xujia; Wen, Yang; Su, Limin; Zhao, Yuanhui

2013-01-01

Prediction of the biodegradability of organic pollutants is an ecologically desirable and economically feasible tool for estimating the environmental fate of chemicals. In this paper, linear and nonlinear relationships between biological oxygen demand (BOD) and molecular descriptors/fragments have been investigated for 1130 organic chemicals. Significant relationships have been observed between the simple molecular descriptors and %BOD for some homologous compounds, but not for the whole set of compounds. Electronic parameters, such as E HOMO and E LUMO , are the dominant factors affecting the biodegradability for some homologous chemicals. However, other descriptors, such as molecular weight, acid dissociation constant and polarity still have a significant impact on the biodegradation. The best global model for %BOD prediction is that developed from a chain-based fragmentation scheme. At the same time, the theoretical relationship between %BOD and molecular descriptors/fragments has been investigated, based on a first-order kinetic process. The %BOD is nonlinearly, rather than linearly, related to the descriptors. The coefficients of determination can be significantly improved by using nonlinear models for the homologous compounds and the whole data set. After analysing 1130 ready and not ready biodegradable compounds using 23 simple descriptors and various fragmentation schemes, it was revealed that biodegradation could be well predicted from a chain-based fragmentation scheme, a decision tree and a %BOD model. The models were capable of separating NRB and RB with an overall accuracy of 87.2%, 83.0% and 82.5%, respectively. The best classification model developed was a chain-based model but it used 155 fragments. The simplest model was a decision tree which only used 10 structural fragments. The effect of structures on the biodegradation has been analysed and the biodegradation pathway and mechanisms have been discussed based on activating and inactivating

Water

Directory of Open Access Journals (Sweden)

E. Sanmuga Priya

2017-05-01

Full Text Available Phytoremediation through aquatic macrophytes treatment system (AMATS for the removal of pollutants and contaminants from various natural sources is a well established environmental protection technique. Water hyacinth (Eichhornia crassipes, a worst invasive aquatic weed has been utilised for various research activities over the last few decades. The biosorption capacity of the water hyacinth in minimising various contaminants present in the industrial wastewater is well studied. The present review quotes the literatures related to the biosorption capacity of the water hyacinth in reducing the concentration of dyestuffs, heavy metals and minimising certain other physiochemical parameters like TSS (total suspended solids, TDS (total dissolved solids, COD (chemical oxygen demand and BOD (biological oxygen demand in textile wastewater. Sorption kinetics through various models, factors influencing the biosorption capacity, and role of physical and chemical modifications in the water hyacinth are also discussed.

Green Walls as an Approach in Grey Water Treatment

Science.gov (United States)

Rysulova, Martina; Kaposztasova, Daniela; Vranayova, Zuzana

2017-10-01

Grey water contributes significantly to waste water parameters such as biochemical oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), total phosphorus (Ptotal), total nitrogen (Ntotal), ammonium, boron, metals, salts, surfactants, synthetic chemicals, oils and greases, xenobiotic substances and microorganisms. Concentration of these pollutants and the water quality highlights the importance of treatment process in grey water systems. Treatment technologies operating under low energy and maintenance are usually preferred, since they are more cost effective for users. Treatment technologies based on natural processes represent an example of such technology including vegetated wall. Main aim of this paper is to introduce the proposal of vegetated wall managing grey water and brief characteristic of proposed system. Is expected that prepared experiment will establish the purifying ability and the potential of green wall application as an efficient treatment technology.

Olive mill wastewater treatment in Jordan: A Review

Science.gov (United States)

Bawab, Abeer Al; Ghannam, Noor; Abu-Mallouh, Saida; Bozeya, Ayat; Abu-Zurayk, Rund A.; Al-Ajlouni, Yazan A.; Alshawawreh, Fida'a.; Odeh, Fadwa; Abu-Dalo, Muna A.

2018-02-01

The environmental impact of olive mill wastewater (OMW) pollution is a public concern. OMW contains high levels of phenols, organic compounds, chemical oxygen demand (COD), biological oxygen demand (BOD), microorganisms, nutrients, and toxic compounds. The treatment of OMW has been investigated by many researchers in the Mediterranean region, using several treatment techniques to remove contaminants from OMW. These techniques include chemical, biological, physiochemical, and biophysical techniques. Surfactants and some adsorbents were used in chemical techniques, anaerobic and aerobic in biological techniques, while the combined treatment methods used Electroosmosis, ozonation and electrocoagulation processes as physiochemical methods, and ultrasonic irradiation combined with aerobic biodegradation as biophysical method. The effects of OMW, whether treated or untreated, have been evaluated on both plants’ growth and soil properties. The treatment methods as well as the environmental impact of OMW in Jordan were summarized in this review.

Characterization of selected municipal solid waste components to estimate their biodegradability.

Science.gov (United States)

Bayard, R; Benbelkacem, H; Gourdon, R; Buffière, P

2018-06-15

Biological treatments of Residual Municipal Solid Waste (RMSW) allow to divert biodegradable materials from landfilling and recover valuable alternative resources. The biodegradability of the waste components needs however to be assessed in order to design the bioprocesses properly. The present study investigated complementary approaches to aerobic and anaerobic biotests for a more rapid evaluation. A representative sample of residual MSW was collected from a Mechanical Biological Treatment (MBT) plant and sorted out into 13 fractions according to the French standard procedure MODECOM™. The different fractions were analyzed for organic matter content, leaching behavior, contents in biochemical constituents (determined by Van Soest's acid detergent fiber method), Biochemical Oxygen Demand (BOD) and Bio-Methane Potential (BMP). Experimental data were statistically treated by Principal Components Analysis (PCA). Cumulative oxygen consumption from BOD tests and cumulative methane production from BMP tests were found to be positively correlated in all waste fractions. No correlation was observed between the results from BOD or BMP bioassays and the contents in cellulose-like, hemicelluloses-like or labile organic compounds. No correlation was observed either with the results from leaching tests (Soluble COD). The contents in lignin-like compounds, evaluated as the non-extracted RES fraction in Van Soest's method, was found however to impact negatively the biodegradability assessed by BOD or BMP tests. Since cellulose, hemicelluloses and lignin are the polymers responsible for the structuration of lignocellulosic complexes, it was concluded that the structural organization of the organic matter in the different waste fractions was more determinant on biodegradability than the respective contents in individual biopolymers. Copyright © 2017 Elsevier Ltd. All rights reserved.

Prolonged aerobic degradation of shredded and pre-composted municipal solid waste: report from a 21-year study of leachate quality characteristics.

Science.gov (United States)

Grisey, Elise; Aleya, Lotfi

2016-01-01

The objective of this study was to assess the degree of long-term waste maturation at a closed landfill (Etueffont, France) over a period of 21 years (1989-2010) through analysis of the physicochemical characteristics of leachates as well as biochemical oxygen demand (BOD), chemical oxygen demand (COD), and metal content in waste. The results show that the leachates, generated in two different sections (older and newer) of the landfill, have low organic, mineral, and metallic loads, as the wastes were mainly of household origin from a rural area where sorting and composting were required. Based on pH and BOD/COD assessments, leachate monitoring in the landfill's newer section showed a rapid decrease in the pollution load over time and an early onset of methanogenic conditions. The closing of the older of the two sections contributed to a significant decline for the majority of parameters, attributable to degradation and leaching. A gradual decreasing trend was observed after waste placement had ceased in the older section, indicating that degradation continued and the waste mass had not yet fully stabilized. At the end of monitoring, leachates from the two landfill linings contained typical old leachates in the maturation period, with a pH ≥ 7 and a low BOD/COD ratio indicating a low level of waste biodegradability. Age actually contributes to a gradual removal of organic, inorganic, and metallic wastes, but it is not the only driving factor behind advanced degradation. The lack of compaction and cover immediately after deposit extended the aerobic degradation phase, significantly reducing the amount of organic matter. In addition, waste shredding improved water infiltration into the waste mass, hastening removal of polluting components through percolation.

Treatment of dye wastewater with permanganate oxidation and in situ formed manganese dioxides adsorption: cation blue as model pollutant.

Science.gov (United States)

Liu, Ruiping; Liu, Huijuan; Zhao, Xu; Qu, Jiuhui; Zhang, Ran

2010-04-15

This study investigated the process of potassium permanganate (KMnO(4)) oxidation and in situ formed hydrous manganese dioxides (deltaMnO(2)) (i.e., KMnO(4) oxidation and deltaMnO(2) adsorption) for the treatment of dye wastewater. The effectiveness of decolorization, removing dissolved organic carbon (DOC), and increasing biodegradable oxygen demand (BOD) were compared among these processes of KMnO(4) oxidation, deltaMnO(2) adsorption, and KMnO(4) oxidation and deltaMnO(2) adsorption. DeltaMnO(2) adsorption contributed to the maximum DOC removal of 65.0%, but exhibited limited capabilities of decolorizing and increasing biodegradability. KMnO(4) oxidation alone at pH 0.5 showed satisfactory decrease of UV-vis absorption peaks, and the maximum BOD(5)/DOC value of 1.67 was achieved. Unfortunately, the DOC removal was as low as 27.4%. Additionally, the great amount of acid for pH adjustment and the much too low pH levels limited its application in practice. KMnO(4) oxidation and deltaMnO(2) adsorption at pH 2.0 was the best strategy prior to biological process, in balancing the objectives of decolorization, DOC removal, and BOD increase. The optimum ratio of KMnO(4) dosage to X-GRL concentration (R(KMnO(4)/X-GRL)) was determined to be 2.5, at which KMnO(4) oxidation and deltaMnO(2) adsorption contributed to the maximal DOC removal of 53.4%. Additionally, the optimum pH for X-GRL treatment was observed to be near 3.0. 2009 Elsevier B.V. All rights reserved.

Management of landfill leachate: The legacy of European Union Directives.

Science.gov (United States)

Brennan, R B; Healy, M G; Morrison, L; Hynes, S; Norton, D; Clifford, E

2016-09-01

Landfill leachate is the product of water that has percolated through waste deposits and contains various pollutants, which necessitate effective treatment before it can be released into the environment. In the last 30years, there have been significant changes in landfill management practices in response to European Union (EU) Directives, which have led to changes in leachate composition, volumes produced and treatability. In this study, historic landfill data, combined with leachate characterisation data, were used to determine the impacts of EU Directives on landfill leachate management, composition and treatability. Inhibitory compounds including ammonium (NH4-N), cyanide, chromium, nickel and zinc, were present in young leachate at levels that may inhibit ammonium oxidising bacteria, while arsenic, copper and silver were present in young and intermediate age leachate at concentrations above inhibitory thresholds. In addition, the results of this study show that while young landfills produce less than 50% of total leachate by volume in the Republic of Ireland, they account for 70% of total annual leachate chemical oxygen demand (COD) load and approximately 80% of total 5-day biochemical oxygen demand (BOD5) and NH4-N loads. These results show that there has been a decrease in the volume of leachate produced per tonne of waste landfilled since enactment of the Landfill Directive, with a trend towards increased leachate strength (particularly COD and BOD5) during the initial five years of landfill operation. These changes may be attributed to changes in landfill management practices following the implementation of the Landfill Directive. However, this study did not demonstrate the impact of decreasing inputs of biodegradable municipal waste on leachate composition. Increasingly stringent wastewater treatment plant (WWTP) emission limit values represent a significant threat to the sustainability of co-treatment of leachate with municipal wastewater. In addition

Water quality and processes affecting dissolved oxygen concentrations in the Blackwater River, Canaan Valley, West Virginia

Science.gov (United States)

Waldron, M.C.; Wiley, J.B.

1996-01-01

The water quality and environmental processes affecting dissolved oxygen were determined for the Blackwater River in Canaan Valley, West Virginia. Canaan Valley is oval-shaped (14 miles by 5 miles) and is located in the Allegheny Mountains at an average elevation of 3,200 feet above sea level. Tourism, population, and real estate development have increased in the past two decades. Most streams in Canaan Valley are a dilute calcium magnesium bicarbonate-type water. Streamwater typicaly was soft and low in alkalinity and dissolved solids. Maximum values for specific conductance, hardness, alkalinity, and dissolved solids occurred during low-flow periods when streamflow was at or near baseflow. Dissolved oxygen concentrations are most sensitive to processes affecting the rate of reaeration. The reaeration is affected by solubility (atmospheric pressure, water temperature, humidity, and cloud cover) and processes that determine stream turbulence (stream depth, width, velocity, and roughness). In the headwaters, photosynthetic dissolved oxygen production by benthic algae can result in supersaturated dissolved oxygen concentrations. In beaver pools, dissolved oxygen consumption from sediment oxygen demand and carbonaceous biochemical oxygen demand can result in dissolved oxygen deficits.

Use of shredded tire chips and tire crumbs as packing media in trickling filter systems for landfill leachate treatment.

Science.gov (United States)

Mondal, B; Warith, M A

2008-08-01

Scrap tire stockpiles are breeding grounds for pests, mosquitoes and west Nile viruses and, thereby, become a potential health risk. This experimental study was carried out in six stages to determine the suitability of shredded tire materials in a trickling filter system to treat landfill leachate. Biochemical oxygen demand (BOD5), chemical oxygen demand (COD) and NH3-N removals were obtained in the range of 81 to 96%, 76 to 90% and 15 to 68%, respectively. The removal of organics appears to be largely related to total dissolved solids reduction in leachate. A sudden increase, from time to time, in organic content of effluent could be attributed to biomass sloughing and clogging in the trickling filters. However, tire crumbs exhibited more consistent organics removal throughout the experimental program. Due to the high surface area of shredded tire chips and crumbs, a layer of biomass, 1-2 mm thick, was attached to them and was sloughed off at an interval of 21 days. Apart from that, as shredded tires are comparatively cheaper than any other usable packing material, tire chips and tire crumbs appeared to be quite promising as packing media in trickling filters for landfill leachate treatment.

A Membrane Process for Recycling Die Lube from Wastewater Solutions

Energy Technology Data Exchange (ETDEWEB)

Eric S. Peterson; Jessica Trudeau; Bill Cleary; Michael Hackett; William A. Greene

2003-04-01

An active-surface membrane technology was used to separate a die lube manufacturing wastewater stream consisting of various oils, hydrocarbons, heavy metals, and silicones. The ultrafiltration membranes reduced organics from initial oil and grease contents by 20–25X, carbon oxygen demand (COD) by 1.5 to 2X, and total organic carbon (TOC) by 0.6, while the biological oxygen demand (BOD) remained constant. The active-surface membranes were not fouled as badly as non-active-surface systems and the active-surface membrane flux levels were consistently higher and more stable than those of the non-active-surface membranes tested. Field testing demonstrated that the rotary microfilter can concentrate the die lube, i.e. remove the glycerin component, and produce a die lube suitable for recycling. The recycling system operated for six weeks with only seven cleaning cycles and no mechanical or electrical failures. Test data and quality records indicate that the die casting scrap was reduced from 8.4 to 7.8%. There is no doubt that this test yielded tremendous results. This separation process presents significant opportunities that can be evaluated further.

A Membrane Process for Recycling Die Lube from Wastewater Solutions

Energy Technology Data Exchange (ETDEWEB)

Peterson, E. S. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Trudeau, J. [Metaldyne, Inc., Twinsburg, OH (United States); Cleary, B. [Metaldyne, Inc., Twinsburg, OH (United States); Hackett, M. [Metaldyne, Inc., Twinsburg, OH (United States); Greene, W. A. [SpinTek FIltrations, LLC, Los Alamitos, CA (United States)

2003-04-30

An active-surface membrane technology was used to separate a die lube manufacturing wastewater stream consisting of various oils, hydrocarbons, heavy metals, and silicones. The ultrafiltration membranes reduced organics from initial oil and grease contents by 20-25X, carbon oxygen demand (COD) by 1.5 to 2X, and total organic carbon (TOC) by 0.6, while the biological oxygen demand (BOD) remained constant. The active-surface membranes were not fouled as badly as non-active-surface systems and the active-surface membrane flux levels were consistently higher and more stable than those of the non-active-surface membranes tested. Field testing demonstrated that the rotary microfilter can concentrate the die lube, i.e. remove the glycerin component, and produce a die lube suitable for recycling. The recycling system operated for six weeks with only seven cleaning cycles and no mechanical or electrical failures. Test data and quality records indicate that the die casting scrap was reduced from 8.4 to 7.8%. There is no doubt that this test yielded tremendous results. This separation process presents significant opportunities that can be evaluated further.

Detecting Long-term Trend of Water Quality Indices of Dong-gang River, Taiwan Using Quantile Regression

Science.gov (United States)

Yang, D.; Shiau, J.

2013-12-01

ABSTRACT BODY: Abstract Surface water quality is an essential issue in water-supply for human uses and sustaining healthy ecosystem of rivers. However, water quality of rivers is easily influenced by anthropogenic activities such as urban development and wastewater disposal. Long-term monitoring of water quality can assess whether water quality of rivers deteriorates or not. Taiwan is a population-dense area and heavily depends on surface water for domestic, industrial, and agricultural uses. Dong-gang River is one of major resources in southern Taiwan for agricultural requirements. The water-quality data of four monitoring stations of the Dong-gang River for the period of 2000-2012 are selected for trend analysis. The parameters used to characterize water quality of rivers include biochemical oxygen demand (BOD), dissolved oxygen (DO), suspended solids (SS), and ammonia nitrogen (NH3-N). These four water-quality parameters are integrated into an index called river pollution index (RPI) to indicate the pollution level of rivers. Although widely used non-parametric Mann-Kendall test and linear regression exhibit computational efficiency to identify trends of water-quality indices, limitations of such approaches include sensitive to outliers and estimations of conditional mean only. Quantile regression, capable of identifying changes over time of any percentile values, is employed in this study to detect long-term trend of water-quality indices for the Dong-gang River located in southern Taiwan. The results show that Dong-gang River 4 stations from 2000 to 2012 monthly long-term trends in water quality.To analyze s Dong-gang River long-term water quality trends and pollution characteristics. The results showed that the bridge measuring ammonia Long-dong, BOD5 measure in that station on a downward trend, DO, and SS is on the rise, River Pollution Index (RPI) on a downward trend. The results form Chau-Jhou station also ahowed simialar trends .more and more near the

Pengaruh Jumlah Eceng Gondok(eichornia Crassipes) Dan Waktu Tinggal Terhadappenurunan Konsentrasi Cod, Bod, Dan Warnadalam Limbah Batik

OpenAIRE

Wahyu A, Diah; Syafrudin, Syafrudin; Zaman, Badrus

2015-01-01

Batik industries is one of any industries that produce wastewater. According to the previous researches, also known that wastewater of batik industries contain organic substances, suspended solid, color, chromium, phenol, and other. Result of the characteristic test show that BOD concentration is about 130,37 mg/l, COD 1376,29 mg/l, also color 10.000 mg/l PtCo. Treatment for wastewater of batik industries is needed since wastewater can be harm to the environment and it can decrease the enviro...

Characterization of a 5-eV neutral atomic oxygen beam facility

Science.gov (United States)

Vaughn, J. A.; Linton, R. C.; Carruth, M. R., Jr.; Whitaker, A. F.; Cuthbertson, J. W.; Langer, W. D.; Motley, R. W.

1991-01-01

An experimental effort to characterize an existing 5-eV neutral atomic oxygen beam facility being developed at Princeton Plasma Physics Laboratory is described. This characterization effort includes atomic oxygen flux and flux distribution measurements using a catalytic probe, energy determination using a commercially designed quadrupole mass spectrometer (QMS), and the exposure of oxygen-sensitive materials in this beam facility. Also, comparisons were drawn between the reaction efficiencies of materials exposed in plasma ashers, and the reaction efficiencies previously estimated from space flight experiments. The results of this study show that the beam facility is capable of producing a directional beam of neutral atomic oxygen atoms with the needed flux and energy to simulate low Earth orbit (LEO) conditions for real time accelerated testing. The flux distribution in this facility is uniform to +/- 6 percent of the peak flux over a beam diameter of 6 cm.

Water quality assessment of the Borska Reka river using the WPI (Water Pollution Index method

Directory of Open Access Journals (Sweden)

Milijašević Dragana

2011-01-01

Full Text Available The Borska Reka river (47 km long, 373 km2 of basin area is located in eastern Serbia and it is the biggest tributary of the river Veliki Timok. It is also one of the most polluted watercourses in Serbia. Using the data of the Republic Hydrometeorological Service of Serbia, the paper analyzes water pollution using the combined physical-chemical WPI index (water pollution index over two periods: 1993-1996 and 2006-2009. The analysis of parameters showed significantly increased values of heavy metals (especially iron and manganese which are indicators of inorganic pollution (primarily because of mining, but also increased values of organic pollution indicators (Biological Oxygen Demand-BOD5, ammonium, coliform germs, as the result of uncontrolled domestic wastewater discharge.

Are macroinvertebrates in high altitude streams affected by oxygen deficiency?

DEFF Research Database (Denmark)

Jacobsen, Dean; Rostgaard, S.; Vásconez, J. J.

2003-01-01

1. The solubility of oxygen in water increases with decreasing temperature. This has led to a general perception of cold, high mountain streams as more oxygen rich than warmer lowland streams, and that macroinvertebrates inhabiting high altitude streams have had no need to adapt to critical oxygen...... conditions. However, this fails to take into account that oxygen solubility declines with decreasing atmospheric pressure, which may be of importance at high altitudes. 2. Based on samples of macroinvertebrate benthos and in situ measurements of respiratory oxygen demand of macroinvertebrates in small...... the mean weight-specific respiratory rate of macroinvertebrates declined by only 50%, from 400 to 3800 m. We suggest that this disproportionately large gap between availability and demand of oxygen at high altitudes may imply a potential oxygen deficiency for the fauna, and we discuss how oxygen deficiency...

Oxygen therapy for cluster headache

DEFF Research Database (Denmark)

Petersen, Anja S; Barloese, Mads Cj; Lund, Nunu Lt

2017-01-01

-controlled, crossover inpatient study, and 102 CH attacks were treated with 100% oxygen delivered by demand valve oxygen (DVO), O2ptimask or simple mask (15 liters/min) or placebo delivered by DVO for 15 minutes. Primary endpoint: Two-point decrease of pain on a five-point rating scale within 15 minutes. Results Only...

Estimating oxygen needs for childhood pneumonia in developing country health systems: a new model for expecting the unexpected.

Directory of Open Access Journals (Sweden)

Beverly D Bradley

Full Text Available Planning for the reliable and cost-effective supply of a health service commodity such as medical oxygen requires an understanding of the dynamic need or 'demand' for the commodity over time. In developing country health systems, however, collecting longitudinal clinical data for forecasting purposes is very difficult. Furthermore, approaches to estimating demand for supplies based on annual averages can underestimate demand some of the time by missing temporal variability.A discrete event simulation model was developed to estimate variable demand for a health service commodity using the important example of medical oxygen for childhood pneumonia. The model is based on five key factors affecting oxygen demand: annual pneumonia admission rate, hypoxaemia prevalence, degree of seasonality, treatment duration, and oxygen flow rate. These parameters were varied over a wide range of values to generate simulation results for different settings. Total oxygen volume, peak patient load, and hours spent above average-based demand estimates were computed for both low and high seasons.Oxygen demand estimates based on annual average values of demand factors can often severely underestimate actual demand. For scenarios with high hypoxaemia prevalence and degree of seasonality, demand can exceed average levels up to 68% of the time. Even for typical scenarios, demand may exceed three times the average level for several hours per day. Peak patient load is sensitive to hypoxaemia prevalence, whereas time spent at such peak loads is strongly influenced by degree of seasonality.A theoretical study is presented whereby a simulation approach to estimating oxygen demand is used to better capture temporal variability compared to standard average-based approaches. This approach provides better grounds for health service planning, including decision-making around technologies for oxygen delivery. Beyond oxygen, this approach is widely applicable to other areas of

Co-treatment of landfill leachate and domestic wastewater using a submerged aerobic biofilter.

Science.gov (United States)

Ferraz, F M; Povinelli, J; Pozzi, E; Vieira, E M; Trofino, J C

2014-08-01

This study used a pilot-scale submerged aerobic biofilter (SAB) to evaluate the co-treatment of domestic wastewater and landfill leachate that was pre-treated by air stripping. The leachate tested volumetric ratios were 0, 2, and 5%. At a hydraulic retention time of 24 h, the SAB was best operated with a volumetric ratio of 2% and removed 98% of the biochemical oxygen demand (BOD), 80% of the chemical oxygen demand (COD) and dissolved organic carbon (DOC), and 90% of the total suspended solids (TSS). A proposed method, which we called the "equivalent in humic acid" (Eq.HA) approach, indicated that the hardly biodegradable organic matter in leachate was removed by partial degradation (71% of DOC Eq.HA removal). Adding leachate at a volumetric ratio of 5%, the concentration of the hardly biodegradable organic matter was decreased primarily as a result of dilution rather than biodegradation, which was confirmed by Fourier transform infrared (FTIR) spectroscopy. The total ammoniacal nitrogen (TAN) was mostly removed (90%) by nitrification, and the SAB performances at the volumetric ratios of 0 and 2% were equal. For the three tested volumetric ratios of leachate (0, 2, and 5%), the concentrations of heavy metals in the treated samples were below the local limits. Copyright © 2014 Elsevier Ltd. All rights reserved.

Stability and oxygen transport property of La0.8Sr0.2Cr0.5Fe0.5O3 -δ

DEFF Research Database (Denmark)

He, Wei; Huang, Hua; Chen, Ming

2014-01-01

vacancies in the lattice. LSCrF powder exposed to flowing concentrated hydrogen for 30 h was found to decompose partially. The decomposition oxygen partial pressure of LSCrF at 950 °C was estimated to be 6.3 × 10- 28 atm from thermodynamic calculations. The stability of LSCrF under an oxygen chemical......The stability of La0.8Sr0.2Cr0.5Fe 0.5O3 -δ (LSCrF) in reducing atmosphere was investigated by examining the extent of its reaction with hydrogen at elevated temperature. LSCrF powder exposed to diluted hydrogen was found to loss a weight of only ~ 0.5%, corresponding to the formation of oxygen...... potential gradient was also examined by exposing a disk-shaped dense sample to air at one side and to reducing atmosphere (CO) at the other side at elevated temperatures. A thin, porous layer was found to form on the CO side surface. An oxygen permeation flux of 2.5 × 10- 7 mol cm- 2 s- 1 was observed...

Thermal expansion behaviour in the oxygen deficient perovskites Sr2BSbO5.5 (B=Ca, Sr, Ba). Competing effects of water and oxygen ordering

International Nuclear Information System (INIS)

Zhou Qingdi; Kennedy, Brendan J.; Avdeev, Maxim

2011-01-01

Neutron diffractions studies reveal the presence of oxygen disorder in the oxygen deficient perovskites Sr 2 BSbO 5.5 (B=Ca, Sr, Ba). Synchrotron X-ray studies demonstrate that these oxides have a double perovskite-type structure with the cell size increasing as the size of the B cation increases from 8.2114(2) A for B=Ca to 8.4408(1) A for B=Ba. It is postulated that a combination of local clustering of the anions and vacancies together with water-water and water-host hydrogen bonds plays a role in defining the volume of the encapsulated water clusters and that changes in the local structure upon heating result in anomalous thermal expansion observed in variable temperature diffraction measurements. - Graphical abstract: The oxides Sr 2 BSbO 5.5 (B=Ca, Sr, Ba) have unusual anion disorder. There is a lag in the contraction in the cell size of Sr 2 CaSbO 5.5 nH 2 O established from X-ray diffraction measurements following the loss of water suggesting changes on the local structure are important. Highlights: → The average structures of the defect perovskites Sr 2 MSbO 5.5 established. → Anion and cation disorder quantified by neutron and synchrotron X-ray diffraction. → Anomalous thermal expansion due to local clustering of anions and vacancies observed.

Oxygen tracer diffusion and surface exchange kinetics in Ba0.5Sr0.5Co0.8Fe0.2O3-δ

NARCIS (Netherlands)

Berenov, A.; Atkinson, A.; Kilner, J.; Ananyev, M.; Eremin, V.; Porotnikova, N.; Farlenkov, A.; Kurumchin, E.; Bouwmeester, Henricus J.M.; Bucher, E.; Sitte, W.

2014-01-01

The oxygen tracer diffusion coefficient, Db⁎, and the oxygen tracer surface exchange coefficient, k, were measured in Ba0.5Sr0.5Co0.8Fe0.2O3 − δ (BSCF5582) over the temperature range of 310–800 °C and the oxygen partial pressure range of 1.3 × 10−3–0.21 bar. Several measurement techniques were used:

Physicochemical assessment of industrial textile effluents of Punjab (India)

Science.gov (United States)

Bhatia, Deepika; Sharma, Neeta Raj; Kanwar, Ramesh; Singh, Joginder

2018-06-01

Urbanization and industrialization are generating huge quantities of untreated wastewater leading to increased water pollution and human diseases in India. The textile industry is one of the leading polluters of surface water and consumes about 200-270 tons of water to produce 1 ton of textile product. The primary objective of the present study was to investigate the pollution potential of textile industry effluent draining into Buddha Nallah stream located in Ludhiana, Punjab (India), and determine the seasonal variation in physicochemical parameters (pH, water temperature, total dissolved solids, total suspended solids, biochemical oxygen demand (BOD) and chemical oxygen demand (COD) of Buddha Nallah water. During summer months, for Site 1 and Site 2, the value of pH was in the alkaline range of 8.78 ± 0.47 and 8.51 ± 0.41, respectively. The values of pH in the rainy season were found to be in the range of 7.38 ± 0.58 and 7.11 ± 0.59 for Site 1 and Site 2, respectively. In the autumn and winter seasons, the average pH values were found to be in the range of 8.58 ± 1.40 and 8.33 ± 0.970, respectively. The maximum mean temperature in summer was recorded as 41.16 ± 4.99 °C, and lowest mean temperature in winter was recorded as 39.25 ± 2.25 °C at Site 2. The suspended solids were found to be highest (143.5 ± 75.01 and 139.66 ± 71.87 mg/L) in autumn for both the sites and lowest (86.50 + 15.10 mg/L) in the rainy season for Site 1. The values of BOD and COD of the textile effluent of both sites during all the seasons ranged from 121-580 to 240-990 mg/L, respectively, much higher than WHO water quality standard of 30 mg/L for BOD and 250 mg/L for COD. The present study deals with the collection of textile industry effluent and its characterization to find out the physicochemical load being drained by the effluent generated from textile industries, on the natural wastewater streams.

Condition assessment survey of onsite sewage disposal systems (OSDSs) in Hawaii.

Science.gov (United States)

Babcock, Roger W; Lamichhane, Krishna M; Cummings, Michael J; Cheong, Gloria H

2014-01-01

Onsite sewage disposal systems (OSDSs) are the third leading cause of groundwater contamination in the USA. The existing condition of OSDSs in the State of Hawaii was investigated to determine whether a mandatory management program should be implemented. Based on observed conditions, OSDSs were differentiated into four categories: 'pass', 'sludge scum', 'potential failure' and 'fail'. Of all OSDSs inspected, approximately 68% appear to be in good working condition while the remaining 32% are failing or are in danger of failing. Homeowner interviews found that 80% of OSDSs were not being serviced in any way. About 70% of effluent samples had values of total-N and total-P greater than typical values and 40% had total suspended solids (TSS) and 5-day biochemical oxygen demand (BOD5) greater than typical values. The performance of aerobic treatment units (ATUs) was no better than septic tanks and cesspools indicating that the State's approach of requiring but not enforcing maintenance contracts for ATUs is not working. In addition, effluent samples from OSDSs located in drinking water wells estimated 2-year capture zones had higher average concentrations of TSS, BOD5, and total-P than units outside of these zones, indicating the potential for contamination. These findings suggest the need to introduce a proactive, life-cycle OSDS management program in the State of Hawaii.

Ethanol Demand in United States Gasoline Production

Energy Technology Data Exchange (ETDEWEB)

Hadder, G.R.

1998-11-24

The Oak Ridge National Laboratory (OWL) Refinery Yield Model (RYM) has been used to estimate the demand for ethanol in U.S. gasoline production in year 2010. Study cases examine ethanol demand with variations in world oil price, cost of competing oxygenate, ethanol value, and gasoline specifications. For combined-regions outside California summer ethanol demand is dominated by conventional gasoline (CG) because the premised share of reformulated gasoline (RFG) production is relatively low and because CG offers greater flexibility for blending high vapor pressure components like ethanol. Vapor pressure advantages disappear for winter CG, but total ethanol used in winter RFG remains low because of the low RFG production share. In California, relatively less ethanol is used in CG because the RFG production share is very high. During the winter in California, there is a significant increase in use of ethanol in RFG, as ethanol displaces lower-vapor-pressure ethers. Estimated U.S. ethanol demand is a function of the refiner value of ethanol. For example, ethanol demand for reference conditions in year 2010 is 2 billion gallons per year (BGY) at a refiner value of $1.00 per gallon (1996 dollars), and 9 BGY at a refiner value of $0.60 per gallon. Ethanol demand could be increased with higher oil prices, or by changes in gasoline specifications for oxygen content, sulfur content, emissions of volatile organic compounds (VOCS), and octane numbers.

Optimized chondrogenesis of ATCD5 cells through sequential regulation of oxygen conditions

DEFF Research Database (Denmark)

Chen, Li; Fink, Trine; Ebbesen, Peter

2006-01-01

, chondrocyte-specific extracellular matrix (ECM) production was monitored. Furthermore, the transcription of collagen II, an early-phase marker, and collagen X, a marker of hypertrophic conversion, was followed by real-time RT-PCR. Low oxygen concentrations between 1 and 9% inhibited chondrogenic conversion......, as evidenced by reduced glycosaminoglycan deposition in the ECM in a manner proportional to the degree of hypoxia. Cells cultured at oxygen concentrations of 12 and 15% underwent a faster and higher degree of early-phase chondrogenesis when compared to control cells cultured at ambient air (21% O2......). For the hypertrophic conversion of the ATDC5 cells, all degrees of hypoxia inhibited collagen X expression in a dose-dependent manner. Short-term culturing of the ATDC5 cells for 6 to 8 days at 12% oxygen with subsequent culturing at 21% for the remainder of the experiment resulted in maximal production of major ECM...

Applicability of Constructed Wetlands for Water Quality Improvement in a Tea Estate Catchment: The Pussellawa Case Study

Directory of Open Access Journals (Sweden)

G. M. P. R. Weerakoon

2018-03-01

Full Text Available Water in agricultural catchments is prone to pollution from agricultural runoff containing nutrients and pesticides, and contamination from the human population working and residing therein. This study examined the quality of water in a drainage stream which runs through a congested network of ‘line houses’ (low-income housing, typically found arranged in straight ‘lines’ on estates in the tea estate catchment area of Pussellawa in central Sri Lanka. The study evaluated the applicability of vertical subsurface flow (VSSF and horizontal subsurface flow (HSSF constructed wetlands for water polishing, as the residents use the stream water for various domestic purposes with no treatment other than possibly boiling. Water flow in the stream can vary significantly over time, and so investigations were conducted at various flow conditions to identify the hydraulic loading rate (HLR bandwidth for wetland polishing applications. Two wetland models of 8 m × 1 m × 0.6 m (length × width × depth were constructed and arranged as VSSF and HSSF units. Stream water was diverted to these units at HLRs of 3.3, 4, 5, 10, 20, and 40 cm/day. Results showed that both VSSF and HSSF wetland units were capable of substantially reducing five-day biochemical oxygen demand (BOD5, total suspended solids (TSS, fecal coliform (FC, total coliform (TC, ammonia nitrogen (NH4+-N, and nitrate nitrogen (NO3−-N up to 20 cm/day HLR, with removal efficiencies of more than 64%, 60%, 90%, 93%, 70%, and 59% for BOD5, TSS, FC, TC, NH4+-N, and NO3−-N, respectively, in the VSSF wetland unit; and more than 66%, 62%, 91%, 90%, 53%, and 77% for BOD5, TSS, FC, TC, NH4+-N, and NO3−-N, respectively, in the HSSF wetland unit.

Mathematical modeling of dissolved oxygen in fish ponds ...

African Journals Online (AJOL)

Mathematical modeling of dissolved oxygen in fish ponds. WJS Mwegoha, ME Kaseva, SMM Sabai. Abstract. A mathematical model was developed to predict the effects of wind speed, light, pH, Temperature, dissolved carbon dioxide and chemical oxygen demand (COD) on Dissolved Oxygen (DO) in fish ponds. The effects ...

On-site phytoremediation applicability assessment in Alur Ilmu, Universiti Kebangsaan Malaysia based on spatial and pollution removal analyses.

Science.gov (United States)

Mahmud, Mohd Hafiyyan; Lee, Khai Ern; Goh, Thian Lai

2017-10-01

The present paper aims to assess the phytoremediation performance based on pollution removal efficiency of the highly polluted region of Alur Ilmu urban river for its applicability of on-site treatment. Thirteen stations along Alur Ilmu were selected to produce thematic maps through spatial distribution analysis based on six water quality parameters of Malaysia's Water Quality Index (WQI) for dry and raining seasons. The maps generated were used to identify the highly polluted region for phytoremediation applicability assessment. Four free-floating plants were tested in treating water samples from the highly polluted region under three different conditions, namely controlled, aerated and normal treatments. The selected free-floating plants were water hyacinth (Eichhornia crassipes), water lettuce (Pistia stratiotes), rose water lettuce (Pistia sp.) and pennywort (Centella asiatica). The results showed that Alur Ilmu was more polluted during dry season compared to raining season based on the water quality analysis. During dry season, four parameters were marked as polluted along Alur Ilmu, namely dissolve oxygen (DO), 4.72 mg/L (class III); ammoniacal nitrogen (NH 3 -N), 0.85 mg/L (class IV); total suspended solid (TSS), 402 mg/L (class V) and biological oxygen demand (BOD), 3.89 mg/L (class III), whereas, two parameters were classed as polluted during raining season, namely total suspended solid (TSS), 571 mg/L (class V) and biological oxygen demand (BOD), 4.01 mg/L (class III). The thematic maps generated from spatial distribution analysis using Kriging gridding method showed that the highly polluted region was recorded at station AL 5. Hence, water samples were taken from this station for pollution removal analysis. All the free-floating plants were able to reduce TSS and COD in less than 14 days. However, water hyacinth showed the least detrimental effect from the phytoremediation process compared to other free-floating plants, thus made it a suitable

Loading Concentrations of Pollutant in Alur Ilmu at UKM Bangi Campus: Event Mean Concentration (EMC) Approach

International Nuclear Information System (INIS)

Haslinur Md Din; Mohd Ekhwan Toriman; Mazlin Mokhtar

2012-01-01

Water pollutant loadings and river discharge are among the basic data used in determining the dynamicity of a river. The input of water quality and river discharge are usually available through the collection of water samples in the field or at the observatory, and are done automatically using the data logger sensor. This paper discusses the concentrations pollutant load water quality and its relationship with discharge (m 3 / s) using Event Mean Concentration (EMC) in the Alur Ilmu, UKM source from the Diptrokarp forest at Hutan Simpan Bangi (2 degree 55' 1 4.72 N 101 degree 46' 5 7.37 E). Alur Ilmu is a 1.79 km long stretching across the main campus of National University of Malaysia before flowing into the Langat River. Water quality was measured using automatic gauging and continuous water quality stations which are installed at downstream of Alur Ilmu (2 degree 55 ' 40.33 N 100 degree 46 ' 47.15 E) and involves in measuring the parameters of total dissolved solid (TDS) and dissolved oxygen (DO). Laboratory analysis carried out for chemical parameters such as ammonia nitrogen (NH 3 -N), total suspended solid (TSS), biochemical oxygen demand (BOD) and chemical oxygen demand (COD) in accordance with guidelines American Public Health Association (APHA, 1995). The normal discharge rate recorded at Alur Ilmu is 0.33 m 3 / s and the wet discharge is 13.04 m 3 / s.The total estimated pollutant loadings according to EMC as DO (18.51±3.01 mg/ L), TDS (794.92±186.72 mg/ L), BOD (11.57±0.28 mg/ L), COD (201.29±1.55 mg/ l), TSS (470.03±27.63 mg/ L) and Ammonia Nitrogen (2.52±0.0 mg/ L). Correlation test showed a direct relationship between rainfall and flow (Q) and several pollutant loadings with R 2 =1 at a significance level of 0.05. The study also classified some of the pollutants concentrations in class III and IV as determined by the Water Quality Index (WQI). (author)

Application of constructed wetlands to the treatment of leachates from a municipal solid waste landfill in Ibadan, Nigeria.

Science.gov (United States)

Aluko, Olufemi Oludare; Sridhar, M K C

2005-06-01

Leachates are wastewater generated principally from landfills and solid waste disposal sites. Leachates emanating from municipal wastes are a major source of surface and groundwater pollution worldwide. Globally, leachates have been implicated in low yield of farm produce, developmental anomalies, low birth weights, leukemia incidence, and other cancers in communities around the site. They have also been implicated in hazards to the environment, loss of biodiversity, and contamination of water sources. At Aba-Eku in Nigeria, leachates are being discharged into the Omi Stream without treatment. A study was conducted on a method of leachate treatment that passes the leachate through constructed wetlands using Ipomoea aquatica (Forsk), a locally available plant found close to the landfill site. The aim of the study was to evolve a sustainable and cost-effective method of treatment whose effluents can be discharged into the Omi Stream with no or minimal impact. The study was descriptive and analytical in design. Samples were collected and analyzed with standard methods for pH, suspended solids (SS), biochemical oxygen demand (BOD), chemical oxygen demand (COD), ammonia, nitrate, and trace metals. Raw leachates were turbid and amber in color and contained suspended solids (197.5 mg/L), ammonia (610.9 mg/L), lead (1.64 mg/L), iron (198.10 mg/L), and manganese (23.20 mg/L). When the leachates were passed through the constructed wetland with eight hours' detention time, effluents showed significant reductions in suspended solids (81.01 percent), BOD (86.03 percent), and ammonia (97.77 percent). The study shows that a constructed wetland is a feasible tool for the treatment of leachates before their disposal into the environment in Nigeria and can help safeguard environmental quality.

Low cost chemical oxygen demand sensor based on electrodeposited nano-copper film

Directory of Open Access Journals (Sweden)

Hamdy H. Hassan

2018-02-01

Full Text Available A commercially available copper electrical cable and pure Cu disk were used as substrates for the electrodeposition of copper nanoparticles (nano-Cu. The surface morphology of the prepared nano-Cu/Cu electrodes was investigated by scanning electron microscope (SEM and energy dispersive X-ray spectrometer (EDX. The bare copper substrates and the nano-copper modified electrodes were utilized and optimized for electrochemical assay of chemical oxygen demand (COD using glycine as a standard. A comparison was made among the four electrodes (i.e., bare and nano-Cu coated copper cable and pure copper disk as potential COD sensors. The oxidation behavior of glycine was investigated on the surface of the prepared sensors using linear sweep voltammetry (LSV. The results indicate significant enhancement of the electrochemical oxidation of glycine by the deposited nano-Cu. The effects of different deposition parameters, such as Cu2+ concentration, deposition potential, deposition time, pH, and scan rate on the response of the prepared sensors were investigated. Under optimized conditions, the optimal nano-Cu based COD sensor exhibited a linear range of 2–595 mg/L, lower limit of detection (LOD as low as 1.07 mg/L (S/N = 3. The developed method exhibited high tolerance level to Cl− ion where 1.0 M Cl− exhibited minimal influence. The sensor was utilized for the detection of COD in different real water samples. The results obtained were validated using the standard dichromate method.

Simulation of an industrial wastewater treatment plant using artificial neural networks and principal components analysis

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Oliveira-Esquerre K.P.

2002-01-01

Full Text Available This work presents a way to predict the biochemical oxygen demand (BOD of the output stream of the biological wastewater treatment plant at RIPASA S/A Celulose e Papel, one of the major pulp and paper plants in Brazil. The best prediction performance is achieved when the data are preprocessed using principal components analysis (PCA before they are fed to a backpropagated neural network. The influence of input variables is analyzed and satisfactory prediction results are obtained for an optimized situation.

Iron oxide minerals in dust-source sediments from the Bodélé Depression, Chad: Implications for radiative properties and Fe bioavailability of dust plumes from the Sahara

Science.gov (United States)

Moskowitz, Bruce M; Reynolds, Richard L.; Goldstein, Harland L.; Beroquo, Thelma; Kokaly, Raymond F.; Bristow, Charlie S

2016-01-01

Atmospheric mineral dust can influence climate and biogeochemical cycles. An important component of mineral dust is ferric oxide minerals (hematite and goethite) which have been shown to influence strongly the optical properties of dust plumes and thus affect the radiative forcing of global dust. Here we report on the iron mineralogy of dust-source samples from the Bodélé Depression (Chad, north-central Africa), which is estimated to be Earth’s most prolific dust producer and may be a key contributor to the global radiative budget of the atmosphere as well as to long-range nutrient transport to the Amazon Basin. By using a combination of magnetic property measurements, Mössbauer spectroscopy, reflectance spectroscopy, chemical analysis, and scanning electron microscopy, we document the abundance and relative amounts of goethite, hematite, and magnetite in dust-source samples from the Bodélé Depression. The partition between hematite and goethite is important to know to improve models for the radiative effects of ferric oxide minerals in mineral dust aerosols. The combination of methods shows (1) the dominance of goethite over hematite in the source sediments, (2) the abundance and occurrences of their nanosize components, and (3) the ubiquity of magnetite, albeit in small amounts. Dominant goethite and subordinate hematite together compose about 2% of yellow-reddish dust-source sediments from the Bodélé Depression and contribute strongly to diminution of reflectance in bulk samples. These observations imply that dust plumes from the Bodélé Depression that are derived from goethite-dominated sediments strongly absorb solar radiation. The presence of ubiquitous magnetite (0.002–0.57 wt%) is also noteworthy for its potentially higher solubility relative to ferric oxide and for its small sizes, including PM iron apportionment is estimated at about 33% in ferric oxide minerals, 1.4% in magnetite, and 65% in ferric silicates. Structural iron in clay

Pecan shell-based granular activated carbon for treatment of chemical oxygen demand (COD) in municipal wastewater.

Science.gov (United States)

Bansode, R R; Losso, J N; Marshall, W E; Rao, R M; Portier, R J

2004-09-01

The present investigation was undertaken to compare the adsorption efficiency of pecan shell-based granular activated carbon with the adsorption efficiency of the commercial carbon Filtrasorb 200 with respect to uptake of the organic components responsible for the chemical oxygen demand (COD) of municipal wastewater. Adsorption efficiencies for these two sets of carbons (experimental and commercial) were analyzed by the Freundlich adsorption model. The results indicate that steam-activated and acid-activated pecan shell-based carbons had higher adsorption for organic matter measured as COD, than carbon dioxide-activated pecan shell-based carbon or Filtrasorb 200 at all the carbon dosages used during the experiment. The higher adsorption may be related to surface area as the two carbons with the highest surface area also had the highest organic matter adsorption. These results show that granular activated carbons made from agricultural waste (pecan shells) can be used with greater effectiveness for organic matter removal from municipal wastewater than a coal-based commercial carbon. Copyright 2004 Elsevier Ltd.

Pollution control in pulp and paper industrial effluents using integrated chemical-biological treatment sequences.

Science.gov (United States)

El-Bestawy, Ebtesam; El-Sokkary, Ibrahim; Hussein, Hany; Keela, Alaa Farouk Abu

2008-11-01

The main objective of the present study was to improve the quality of pulp and paper industrial wastewater of two local mills RAKTA and El-Ahlia, Alexandria, Egypt, and to bring their pollutant contents to safe discharge levels. Quality improvement was carried out using integrated chemical and biological treatment approaches after their optimization. Chemical treatment (alum, lime, and ferric chloride) was followed by oxidation using hydrogen peroxide and finally biological treatment using activated sludge (90 min for RAKTA and 60 min for El-Ahlia effluents). Chemical coagulation produced low-quality effluents, while pH adjustment during coagulation treatment did not enhance the quality of the effluents. Maximum removal of the tested pollutants was achieved using the integrated treatment and the pollutants recorded residual concentrations (RCs) of 34.67, 17.33, 0.13, and 0.43 mg/l and 15.0, 11.0, 0.0, and 0.13 mg/l for chemical oxygen demand (COD), biochemical oxygen demand (BOD5), tannin and lignin, and silica in RAKTA and El-Ahlia effluents, respectively, all of which were below their maximum permissible limits (MPLs) for the safe discharge into water courses. Specific oxygen uptake rate (SOUR) and sludge volume index (SVI) values reflect good conditions and healthy activated sludge. Based on the previous results, optimized conditions were applied as bench scale on the raw effluents of RAKTA and El-Ahlia via the batch chemical and the biological treatment sequences proposed. For RAKTA effluents, the sequence was as follows: (1) coagulation with 375 mg/l FeCl3, (2) oxidation with 50 mg/l hydrogen peroxide, and (3) biological treatment using activated sludge with 2,000 mg/l initial concentration and 90 min hydraulic retention time (HRT), while for El-Ahlia raw effluents, the sequence was (1) coagulation with 250 mg/l FeCl3, (2) oxidation with 45 mg/l hydrogen peroxide, and (3) biological treatment using activated sludge with 2,000 mg/l initial concentration and 60

The Analysis of Septic Tank Performance in Regard to Suspended Solids and Organic Matter Removal

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Ala Kirjanova

2011-12-01

Full Text Available Abstract 117 The aim of this work was to evaluate the removal of suspended solids (SS and 7-day biochemical oxygen demand (BOD7 in a three chamber septic tank depending on theoretical wastewater retention time and the degree of septic tank cleanliness. It was found out that the performance of the septic tank depended on the degree of its cleanliness: when the septic tank was clean and retention time was three days, SS and BOS7 removal efficiency was 77±10% and 67±14% respectively, whereas two months later, after septic tank desludging, SS removal efficiency decreased to 53±22% and BOD7 to 32±31%. The performance of the septic tank also depended on theoretical wastewater retention time: when some amount of solids was accumulated at the bottom of the septic tank and wastewater retention time was one day, SS and BOS7 removal efficiency was 45±40% and 33±16% respectively; when retention time was three days, SS removal efficiency increased to 53±22% but BOD7 removal efficiency remained similar to one day retention time, i.e. 32±31%.Article in Lithuanian

Application of water quality models to rivers in Johor

Science.gov (United States)

Chii, Puah Lih; Rahman, Haliza Abd.

2017-08-01

River pollution is one the most common hazard in many countries in the world, which includes Malaysia. Many rivers have been polluted because of the rapid growth in industrialization to support the country's growing population and economy. Domestic and industrial sewage, agricultural wastes have polluted the rivers and will affect the water quality. Based on the Malaysia Environment Quality Report 2007, the Department of Environment (DOE) has described that one of the major pollutants is Biochemical Oxygen Demand (BOD). Data from DOE in 2004, based on BOD, 18 river basins were classified polluted, 37 river basins were slightly polluted and 65 river basins were in clean condition. In this paper, two models are fitted the data of rivers in Johor state namely Streeter-Phelps model and nonlinear regression (NLR) model. The BOD concentration data for the two rivers in Johor state from year 1981 to year 1990 is analyzed. To estimate the parameters for the Streeter-Phelps model and NLR model, this study focuses on the weighted least squares and Gauss-Newton method respectively. Based on the value of Mean Square Error, NLR model is a better model compared to Streeter-Phelps model.

Crouch severity is a poor predictor of elevated oxygen consumption in cerebral palsy.

Science.gov (United States)

Steele, Katherine M; Shuman, Benjamin R; Schwartz, Michael H

2017-07-26

Children with cerebral palsy (CP) expend more energy to walk compared to typically-developing peers. One of the most prevalent gait patterns among children with CP, crouch gait, is often singled out as especially exhausting. The dynamics of crouch gait increase external flexion moments and the demand on extensor muscles. This elevated demand is thought to dramatically increase energy expenditure. However, the impact of crouch severity on energy expenditure has not been investigated among children with CP. We evaluated oxygen consumption and gait kinematics for 573 children with bilateral CP. The average net nondimensional oxygen consumption during gait of the children with CP (0.18±0.06) was 2.9 times that of speed-matched typically-developing peers. Crouch severity was only modestly related to oxygen consumption, with measures of knee flexion angle during gait explaining only 5-20% of the variability in oxygen consumption. While knee moment and muscle activity were moderately to strongly correlated with crouch severity (r 2 =0.13-0.73), these variables were only weakly correlated with oxygen consumption (r 2 =0.02-0.04). Thus, although the dynamics of crouch gait increased muscle demand, these effects did not directly result in elevated energy expenditure. In clinical gait analysis, assumptions about an individual's energy expenditure should not be based upon kinematics or kinetics alone. Identifying patient-specific factors that contribute to increased energy expenditure may provide new pathways to improve gait for children with CP. Copyright © 2017 Elsevier Ltd. All rights reserved.

Optimizing basin-scale coupled water quantity and water quality management with stochastic dynamic programming

DEFF Research Database (Denmark)

Davidsen, Claus; Liu, Suxia; Mo, Xingguo

2015-01-01

Few studies address water quality in hydro-economic models, which often focus primarily on optimal allocation of water quantities. Water quality and water quantity are closely coupled, and optimal management with focus solely on either quantity or quality may cause large costs in terms of the oth......-er component. In this study, we couple water quality and water quantity in a joint hydro-economic catchment-scale optimization problem. Stochastic dynamic programming (SDP) is used to minimize the basin-wide total costs arising from water allocation, water curtailment and water treatment. The simple water...... quality module can handle conservative pollutants, first order depletion and non-linear reactions. For demonstration purposes, we model pollutant releases as biochemical oxygen demand (BOD) and use the Streeter-Phelps equation for oxygen deficit to compute the resulting min-imum dissolved oxygen...

Impacts of Catfish Effluents on Water Quality Parameters of Majidun Stream, South-West, Nigeria

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O. E. Omofunmi

2017-06-01

Full Text Available There has been a great concern about the level of safety of surface waters, especially in developing countries where there is an exponential increase in water pollution and water-borne diseases. The aim of this study was to assess the effect of catfish pond effluents on water quality of stream water where five catfish farms were located. Water samples were taken on monthly basis, 20 cm of below water surface from the streams that receive effluents from neighboring fishponds. Water quality indicators like dissolved oxygen, biochemical oxygen demand (BOD5, nitrate, nitrite, water temperature, ammonia and Hydrogen ion Concentration (pH were examined in the sampled waters in accordance with the American Public Health Association standards. The average values of water quality indicators examined at effluents and non-effluents discharged sites of the stream indicated that water (24.6 ± 0.2, 24.2 ±0.1, (7.29±0.30, 7.30±0.10, (6.90±0.4, 7.07±0.1 mg/l, (0.40±0.04, 0.27±0.01, (3.77±0.26, 2.34±0.16 mg/l, (3.59±0.11, 2.80±0.02 mg/l and (3.51±0.24, 2.46±0.21 mg/l at (p≥0.05 respectively for temperature, pH, dissolved oxygen, total ammonia, total nitrogen, total phosphorus, and BODs. They were significant differences (P 0.05 excepts temperature and pH, between values obtained at effluents discharged and non-effluents discharged sites, indicating that improper discharges of catfish pond effluents could resulted into environmental contamination

Data on treatment of sewage wastewater by electrocoagulation using punched aluminum electrode and characterization of generated sludge

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Vinita Khandegar

2018-06-01

Full Text Available The electrocoagulation setup must be optimized in order to design an economically feasible process. Therefore, in this work, the effect of the punched aluminum electrode on the performance of the electrocoagulation (EC has been investigated. A series of experiments were performed for treatment of sewage wastewater using plane electrode and compare with punched electrodes. Effect of contact time, voltage, electrode spacing and stirring speed has been optimized for removal of Biochemical oxygen demand (BOD and Total dissolved solids (TDS. It was observed that the performance of electrocoagulation process increased using punched electrode. Also, the less operating cost noticed in punched electrode as compared to a plane electrode for (70–80% removal of BOD and TDS. These data would be useful in designing of an EC reactor to obtain high removal efficiency at low energy consumption. Keywords: Electrocoagulation, Sewage wastewater, Aluminum, Plane, Punched electrode

Assessment of On-Site Treatment Process of Institutional Building’s Wastewater

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Motasem N. Saidan

2018-03-01

Full Text Available This study is conducted to investigate the characteristics of outflow wastewater of the 1 m3 on-site wastewater treatment unit on the basis of the testing and measurement data of the samples that were taken during the study monitored period (August 2017 to January 2018. For this purpose, samples were taken on a weekly basis from the treated wastewater effluent and five quality parameters (biochemical oxygen demand (BOD, chemical oxygen demand (COD, total suspended solids (TSS, pH, E-coli counts were monitored and measured. The average values of the five parameters were compared with the Jordanian standard maximum values, and water reuse in irrigation of plants classifications have been assessed and investigated. Average values of BOD, COD, TSS, pH, and E-coli in treated wastewater were 11 mg/L, 104 mg/L, 15 mg/L, 7.51, and 387 counts, respectively. The installation of in-line ultraviolet (UV unit in recirculating delivery system played a vital role in the reduction of counts far below the permissible maximum level (1000 counts. Based on national and international standards and criteria, results showed that the treated wastewater is suitable for the irrigation of two classifications of plants: (i Fruit trees, road-green sides outside cities, and green landscape; (ii Crops, commercial crops, and forest trees. Hence, such very low water flow rate treatment system can be utilized in refugees’ camps and water scarce residential areas in Jordan.

An innovative modeling approach using Qual2K and HEC-RAS integration to assess the impact of tidal effect on River Water quality simulation.

Science.gov (United States)

Fan, Chihhao; Ko, Chun-Han; Wang, Wei-Shen

2009-04-01

Water quality modeling has been shown to be a useful tool in strategic water quality management. The present study combines the Qual2K model with the HEC-RAS model to assess the water quality of a tidal river in northern Taiwan. The contaminant loadings of biochemical oxygen demand (BOD), ammonia nitrogen (NH(3)-N), total phosphorus (TP), and sediment oxygen demand (SOD) are utilized in the Qual2K simulation. The HEC-RAS model is used to: (i) estimate the hydraulic constants for atmospheric re-aeration constant calculation; and (ii) calculate the water level profile variation to account for concentration changes as a result of tidal effect. The results show that HEC-RAS-assisted Qual2K simulations taking tidal effect into consideration produce water quality indices that, in general, agree with the monitoring data of the river. Comparisons of simulations with different combinations of contaminant loadings demonstrate that BOD is the most import contaminant. Streeter-Phelps simulation (in combination with HEC-RAS) is also performed for comparison, and the results show excellent agreement with the observed data. This paper is the first report of the innovative use of a combination of the HEC-RAS model and the Qual2K model (or Streeter-Phelps equation) to simulate water quality in a tidal river. The combination is shown to provide an alternative for water quality simulation of a tidal river when available dynamic-monitoring data are insufficient to assess the tidal effect of the river.

Sewage treatment in integrated system of UASB reactor and duckweed pond and reuse for aquaculture.

Science.gov (United States)

Mohapatra, D P; Ghangrekar, M M; Mitra, A; Brar, S K

2012-06-01

The performance of a laboratory-scale upflow anaerobic sludge blanket (UASB) reactor and a duckweed pond containing Lemna gibba was investigated for suitability for treating effluent for use in aquaculture. While treating low-strength sewage having a chemical oxygen demand (COD) of typically less than 200 mg/L, with an increase in hydraulic retention time (HRT) from 10.04 to 33.49 h, COD removal efficiency of the UASB reactor decreased owing to a decrease in organic loading rate (OLR) causing poor mixing in the reactor. However, even at the lower OLR (0.475 kg COD/(m3 x d)), the UASB reactor gave a removal efficiency of 68% for COD and 74% for biochemical oxygen demand (BOD). The maximum COD, BOD, ammonia-nitrogen and phosphate removal efficiencies of the duckweed pond were 40.77%, 38.01%, 61.87% and 88.57%, respectively. Decreasing the OLR by increasing the HRT resulted in an increase in efficiency of the duckweed pond for removal of ammonia-nitrogen and phosphate. The OLR of 0.005 kg COD/(m2 x d) and HRT of 108 h in the duckweed pond satisfied aquaculture quality requirements. A specific growth rate of 0.23% was observed for tilapia fish fed with duckweed harvested from the duckweed pond. The economic analysis proved that it was beneficial to use the integrated system of a UASB reactor and a duckweed pond for treatment of sewage.

Diazonium Functionalisation of Carbon Nanotubes for Specific Orientation of Multicopper Oxidases: Controlling Electron Entry Points and Oxygen Diffusion to the Enzyme.

Science.gov (United States)

Lalaoui, Noémie; Holzinger, Michael; Le Goff, Alan; Cosnier, Serge

2016-07-18

We report the controlled orientation of bilirubin oxidases (BOD) from Myrothecium verrucaria on multiwalled carbon nanotubes (MWCNTs) functionalised by electrografting of 6-carboxynaphthalenediazonium and 4-(2-aminoethyl)benzenediazonium salts. On negatively charged naphthoate-modified MWCNTs, a high-potential (0.44 V vs. SCE) oxygen reduction electrocatalysis is observed, occurring via the T1 copper centre. On positively charged ammonium-modified MWCNTs, a low-potential (0.15 V) oxygen reduction electrocatalysis is observed, occurring through a partially oxidised state of the T2/T3 trinuclear copper cluster. Finally, chemically modified naphthoate MWCNTs exhibit high bioelectrocatalytic current densities of 3.9 mA cm(-2) under air at gas-diffusion electrode. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Biochemical process of low level radioactive liquid simulation waste containing detergent

International Nuclear Information System (INIS)

Kundari, Noor Anis; Putra, Sugili; Mukaromah, Umi

2015-01-01

Research of biochemical process of low level radioactive liquid waste containing detergent has been done. Thse organic liquid wastes are generated in nuclear facilities such as from laundry. The wastes that are cotegorized as hazard and poison materials are also radioactive. It must be treated properly by detoxification of the hazard and decontamination of the radionuclides to ensure that the disposal of the waste meets the requirement of standard quality of water. This research was intended to determine decontamination factor and separation efficiensies, its kinetics law, and to produce a supernatant that ensured the environmental quality standard. The radioactive element in the waste was thorium with activity of 5.10 −5 Ci/m 3 . The radioactive liquid waste which were generated in simulation plant contains detergents that was further processed by aerobic biochemical process using SGB 103 bacteria in a batch reactor equipped with aerators. Two different concentration of samples were processed and analyzed for 212 hours and 183 hours respectively at a room temperature. The product of this process is a liquid phase called as supernatant and solid phase material called sludge. The chemical oxygen demand (COD), biological oxygen demand (BOD), suspended solid (SS), and its alpha activity were analyzed. The results show that the decontamination factor and the separation efficiency of the lower concentration samples are higher compared to the samples with high concentration. Regarding the decontamination factor, the result for 212 hours processing of waste with detergent concentration of 1.496 g/L was 3.496 times, whereas at the detergent concentration of 0.748 g/L was 15.305 times for 183 hours processing. In case of the separation efficiency, the results for both samples were 71.396% and 93.465% respectively. The Bacterial growth kinetics equation follow Monod’s model and the decreasing of COD and BOD were first order with the rate constant of 0.01 hour −1

Biochemical process of low level radioactive liquid simulation waste containing detergent

Energy Technology Data Exchange (ETDEWEB)

Kundari, Noor Anis, E-mail: nooranis@batan.go.id; Putra, Sugili; Mukaromah, Umi [Sekolah Tinggi Teknologi Nuklir – Badan Tenaga Nuklir Nasional Jl. Babarsari P.O. BOX 6101 YKBB Yogyakarta 55281 Telp : (0274) 48085, 489716, Fax : (0274) 489715 (Indonesia)

2015-12-29

Research of biochemical process of low level radioactive liquid waste containing detergent has been done. Thse organic liquid wastes are generated in nuclear facilities such as from laundry. The wastes that are cotegorized as hazard and poison materials are also radioactive. It must be treated properly by detoxification of the hazard and decontamination of the radionuclides to ensure that the disposal of the waste meets the requirement of standard quality of water. This research was intended to determine decontamination factor and separation efficiensies, its kinetics law, and to produce a supernatant that ensured the environmental quality standard. The radioactive element in the waste was thorium with activity of 5.10{sup −5} Ci/m{sup 3}. The radioactive liquid waste which were generated in simulation plant contains detergents that was further processed by aerobic biochemical process using SGB 103 bacteria in a batch reactor equipped with aerators. Two different concentration of samples were processed and analyzed for 212 hours and 183 hours respectively at a room temperature. The product of this process is a liquid phase called as supernatant and solid phase material called sludge. The chemical oxygen demand (COD), biological oxygen demand (BOD), suspended solid (SS), and its alpha activity were analyzed. The results show that the decontamination factor and the separation efficiency of the lower concentration samples are higher compared to the samples with high concentration. Regarding the decontamination factor, the result for 212 hours processing of waste with detergent concentration of 1.496 g/L was 3.496 times, whereas at the detergent concentration of 0.748 g/L was 15.305 times for 183 hours processing. In case of the separation efficiency, the results for both samples were 71.396% and 93.465% respectively. The Bacterial growth kinetics equation follow Monod’s model and the decreasing of COD and BOD were first order with the rate constant of 0

Biochemical process of low level radioactive liquid simulation waste containing detergent

Science.gov (United States)

Kundari, Noor Anis; Putra, Sugili; Mukaromah, Umi

2015-12-01

Research of biochemical process of low level radioactive liquid waste containing detergent has been done. Thse organic liquid wastes are generated in nuclear facilities such as from laundry. The wastes that are cotegorized as hazard and poison materials are also radioactive. It must be treated properly by detoxification of the hazard and decontamination of the radionuclides to ensure that the disposal of the waste meets the requirement of standard quality of water. This research was intended to determine decontamination factor and separation efficiensies, its kinetics law, and to produce a supernatant that ensured the environmental quality standard. The radioactive element in the waste was thorium with activity of 5.10-5 Ci/m3. The radioactive liquid waste which were generated in simulation plant contains detergents that was further processed by aerobic biochemical process using SGB 103 bacteria in a batch reactor equipped with aerators. Two different concentration of samples were processed and analyzed for 212 hours and 183 hours respectively at a room temperature. The product of this process is a liquid phase called as supernatant and solid phase material called sludge. The chemical oxygen demand (COD), biological oxygen demand (BOD), suspended solid (SS), and its alpha activity were analyzed. The results show that the decontamination factor and the separation efficiency of the lower concentration samples are higher compared to the samples with high concentration. Regarding the decontamination factor, the result for 212 hours processing of waste with detergent concentration of 1.496 g/L was 3.496 times, whereas at the detergent concentration of 0.748 g/L was 15.305 times for 183 hours processing. In case of the separation efficiency, the results for both samples were 71.396% and 93.465% respectively. The Bacterial growth kinetics equation follow Monod's model and the decreasing of COD and BOD were first order with the rate constant of 0.01 hour-1.

Iron oxide minerals in dust-source sediments from the Bodélé Depression, Chad: Implications for radiative properties and Fe bioavailability of dust plumes from the Sahara

Science.gov (United States)

Moskowitz, Bruce M; Reynolds, Richard L.; Goldstein, Harland L.; Beroquo, Thelma; Kokaly, Raymond F.; Bristow, Charlie S

2016-01-01

Atmospheric mineral dust can influence climate and biogeochemical cycles. An important component of mineral dust is ferric oxide minerals (hematite and goethite) which have been shown to influence strongly the optical properties of dust plumes and thus affect the radiative forcing of global dust. Here we report on the iron mineralogy of dust-source samples from the Bodélé Depression (Chad, north-central Africa), which is estimated to be Earth’s most prolific dust producer and may be a key contributor to the global radiative budget of the atmosphere as well as to long-range nutrient transport to the Amazon Basin. By using a combination of magnetic property measurements, Mössbauer spectroscopy, reflectance spectroscopy, chemical analysis, and scanning electron microscopy, we document the abundance and relative amounts of goethite, hematite, and magnetite in dust-source samples from the Bodélé Depression. The partition between hematite and goethite is important to know to improve models for the radiative effects of ferric oxide minerals in mineral dust aerosols. The combination of methods shows (1) the dominance of goethite over hematite in the source sediments, (2) the abundance and occurrences of their nanosize components, and (3) the ubiquity of magnetite, albeit in small amounts. Dominant goethite and subordinate hematite together compose about 2% of yellow-reddish dust-source sediments from the Bodélé Depression and contribute strongly to diminution of reflectance in bulk samples. These observations imply that dust plumes from the Bodélé Depression that are derived from goethite-dominated sediments strongly absorb solar radiation. The presence of ubiquitous magnetite (0.002–0.57 wt%) is also noteworthy for its potentially higher solubility relative to ferric oxide and for its small sizes, including PM bioavailability to marine and terrestrial ecosystems.

Separation of metabolic supply and demand: aerobic glycolysis as a normal physiological response to fluctuating energetic demands in the membrane.

Science.gov (United States)

Epstein, Tamir; Xu, Liping; Gillies, Robert J; Gatenby, Robert A

2014-01-01

Cancer cells, and a variety of normal cells, exhibit aerobic glycolysis, high rates of glucose fermentation in the presence of normal oxygen concentrations, also known as the Warburg effect. This metabolism is considered abnormal because it violates the standard model of cellular energy production that assumes glucose metabolism is predominantly governed by oxygen concentrations and, therefore, fermentative glycolysis is an emergency back-up for periods of hypoxia. Though several hypotheses have been proposed for the origin of aerobic glycolysis, its biological basis in cancer and normal cells is still not well understood. We examined changes in glucose metabolism following perturbations in membrane activity in different normal and tumor cell lines and found that inhibition or activation of pumps on the cell membrane led to reduction or increase in glycolysis, respectively, while oxidative phosphorylation remained unchanged. Computational simulations demonstrated that these findings are consistent with a new model of normal physiological cellular metabolism in which efficient mitochondrial oxidative phosphorylation supplies chronic energy demand primarily for macromolecule synthesis and glycolysis is necessary to supply rapid energy demands primarily to support membrane pumps. A specific model prediction was that the spatial distribution of ATP-producing enzymes in the glycolytic pathway must be primarily localized adjacent to the cell membrane, while mitochondria should be predominantly peri-nuclear. The predictions were confirmed experimentally. Our results show that glycolytic metabolism serves a critical physiological function under normoxic conditions by responding to rapid energetic demand, mainly from membrane transport activities, even in the presence of oxygen. This supports a new model for glucose metabolism in which glycolysis and oxidative phosphorylation supply different types of energy demand. Cells use efficient but slow-responding aerobic metabolism

Effects of copper particles on a model septic system's function and microbial community.

Science.gov (United States)

Taylor, Alicia A; Walker, Sharon L

2016-03-15

There is concern surrounding the addition of nanoparticles into consumer products due to toxicity potential and the increased risk of human and environmental exposures to these particles. Copper nanoparticles are found in many common consumer goods; therefore, the disposal and subsequent interactions between potentially toxic Cu-based nanoparticles and microbial communities may have detrimental impacts on wastewater treatment processes. This study investigates the effects of three copper particles (micron- and nano-scale Cu particles, and a nano-scale Cu(OH)2-based fungicide) on the function and operation of a model septic tank. Septic system analyses included water quality evaluations and microbial community characterizations to detect changes in and relationships between the septic tank function and microbial community phenotype/genotype. As would be expected for optimal wastewater treatment, biological oxygen demand (BOD5) was reduced by at least 63% during nano-scale Cu exposure, indicating normal function. pH was reduced to below the optimum anaerobic fermentation range during the micro Cu exposure, suggesting incomplete degradation of organic waste may have occurred. The copper fungicide, Cu(OH)2, caused a 57% increase in total organic carbon (TOC), which is well above the typical range for septic systems and also corresponded to increased BOD5 during the majority of the Cu(OH)2 exposure. The changes in TOC and BOD5 demonstrate that the system was improperly treating waste. Overall, results imply individual exposures to the three Cu particles caused distinct disruptions in septic tank function. However, it was observed that the system was able to recover to typical operating conditions after three weeks post-exposure. These results imply that during periods of Cu introduction, there are likely pulses of improper removal of total organic carbon and significant changes in pH not in the optimal range for the system. Copyright © 2016 Elsevier Ltd. All rights

Effect of deposition temperature & oxygen pressure on mechanical properties of (0.5) BZT-(0.5)BCT ceramic thin films

Science.gov (United States)

Sailaja, P.; Kumar, N. Pavan; Rajalakshmi, R.; Kumar, R. Arockia; Ponpandian, N.; Prabahar, K.; Srinivas, A.

2018-05-01

Lead free ferroelectric thin films of {(0.5) BZT-(0.5) BCT} (termed as BCZT) were deposited on Pt/TiO2/SiO2/Si substrates by pulsed laser deposition at four deposition temperatures 600, 650, 700, 750°C and at two oxygen pressures viz. 75mtorr and 100 mtorr using BCZT ceramic target (prepared by solid state sintering method). The effect of deposition temperature and oxygen pressure on the structure, microstructure and mechanical properties of BCZT films were studied. X-ray diffraction patterns of deposited films confirm tetragonal crystal symmetry and the crystallinity of the films increases with increasing deposition temperature. Variation in BCZT grain growth was observed when the films are deposited at different temperatures andoxygen pressures respectively. The mechanical properties viz. hardness and elastic modulus were also found to be high with increase in the deposition temperature and oxygen pressure. The results will be discussed.

Determination of water quality at lake of Engineering at UKM campus Bangi: Towards integrated water resources management

International Nuclear Information System (INIS)

Mazlin Mokhtar; Othman Abdul Karim

2008-01-01

Integrated Water Resources Management (IWRM) is a process, which promotes the coordinated development and management of water, land and related resources, in order to maximize the resultant economic and social welfare in an equitable manner without compromising the sustainability of vital ecosystem. A study on the water quality of the Engineering Lake, UKM Bangi Campus was carried out to determine the water quality, and compare it with the Interim National Water Quality Standard (INWQS) (DOE, 2001), followed by estimation of its Water Quality Index (WQI) based on six selected parameters. The purpose of this study was to identify the possible causes of the water pollution and level of this pollution at the lake. The comparisons of concentration values measured during dry days with those on rainy were performed using suitable statistical methods. Water quality parameters that were measured are pH, temperature, dissolve oxygen (DO), conductivity, turbidity, total suspended solids (TSS), biochemical oxygen demand (BOD), chemical oxygen demand (COD), ammoniacal-nitrogen, lead and cadmium. Temperature, pH, conductivity, dissolved oxygen and turbidity were measured in situ by using calibrated meters, whilst metal concentrations were determined by using Atomic Absorption Spectrophotometer (AAS). Methods of sampling and water analyses were performed according to recommendations that were outlined by the American Public Health Association (APHA, 1998). On normal days, the inflow and the outflow of the lake were estimated to be 0.057 ± 0.024 m 3 / s inflows and 0.052 ± 0.018 m 3 / s outflows. The theoretical retention time of the lake water with a mean depth of 1.5 m and area of 18,000 m 2 was 62.5 ± 37.6 days. On the normal days, the estimated total amounts of materials that were present in the lake were DO (200.88 ± 28.25 kg), TSS (163.78 ± 18.19 kg), NH-N (12.65 ± 13.90 kg), BOD (41.90 ± 23.95 kg), COD (1605.58 ± 74.68 kg), Pb (9.50 ± 0.90 kg) and Cd (2.81 ± 0

A Comprehensive Review on Water Quality Parameters Estimation Using Remote Sensing Techniques

Directory of Open Access Journals (Sweden)

Mohammad Haji Gholizadeh

2016-08-01

Full Text Available Remotely sensed data can reinforce the abilities of water resources researchers and decision makers to monitor waterbodies more effectively. Remote sensing techniques have been widely used to measure the qualitative parameters of waterbodies (i.e., suspended sediments, colored dissolved organic matter (CDOM, chlorophyll-a, and pollutants. A large number of different sensors on board various satellites and other platforms, such as airplanes, are currently used to measure the amount of radiation at different wavelengths reflected from the water’s surface. In this review paper, various properties (spectral, spatial and temporal, etc. of the more commonly employed spaceborne and airborne sensors are tabulated to be used as a sensor selection guide. Furthermore, this paper investigates the commonly used approaches and sensors employed in evaluating and quantifying the eleven water quality parameters. The parameters include: chlorophyll-a (chl-a, colored dissolved organic matters (CDOM, Secchi disk depth (SDD, turbidity, total suspended sediments (TSS, water temperature (WT, total phosphorus (TP, sea surface salinity (SSS, dissolved oxygen (DO, biochemical oxygen demand (BOD and chemical oxygen demand (COD.

Peroxone mineralization of chemical oxygen demand for direct potable water reuse: Kinetics and process control.

Science.gov (United States)

Wu, Tingting; Englehardt, James D

2015-04-15

Mineralization of organics in secondary effluent by the peroxone process was studied at a direct potable water reuse research treatment system serving an occupied four-bedroom, four bath university residence hall apartment. Organic concentrations were measured as chemical oxygen demand (COD) and kinetic runs were monitored at varying O3/H2O2 dosages and ratios. COD degradation could be accurately described as the parallel pseudo-1st order decay of rapidly and slowly-oxidizable fractions, and effluent COD was reduced to below the detection limit (<0.7 mg/L). At dosages ≥4.6 mg L(-1) h(-1), an O3/H2O2 mass ratio of 3.4-3.8, and initial COD <20 mg/L, a simple first order decay was indicated for both single-passed treated wastewater and recycled mineral water, and a relationship is proposed and demonstrated to estimate the pseudo-first order rate constant for design purposes. At this O3/H2O2 mass ratio, ORP and dissolved ozone were found to be useful process control indicators for monitoring COD mineralization in secondary effluent. Moreover, an average second order rate constant for OH oxidation of secondary effluent organics (measured as MCOD) was found to be 1.24 × 10(7) ± 0.64 × 10(7) M(-1) S(-1). The electric energy demand of the peroxone process is estimated at 1.73-2.49 kW h electric energy for removal of one log COD in 1 m(3) secondary effluent, comparable to the energy required for desalination of medium strength seawater. Advantages/disadvantages of the two processes for municipal wastewater reuse are discussed. Copyright © 2015 Elsevier Ltd. All rights reserved.

Assessment of the technological reliability of a hybrid constructed wetland for wastewater treatment in a mountain eco-tourist farm in Poland.

Science.gov (United States)

Jucherski, Andrzej; Nastawny, Maria; Walczowski, Andrzej; Jóźwiakowski, Krzysztof; Gajewska, Magdalena

2017-06-01

The aim of the present study was to assess the technological reliability of a domestic hybrid wastewater treatment installation consisting of a classic three-chambered (volume 6 m 3 ) septic tank, a vertical flow trickling bed filled with granules of a calcinated clay material (KERAMZYT), a special wetland bed constructed on a slope, and a permeable pond used as a receiver. The test treatment plant was located at a mountain eco-tourist farm on the periphery of the spa municipality of Krynica-Zdrój, Poland. The plant's operational reliability in reducing the concentration of organic matter, measured as biochemical oxygen demand (BOD 5 ) and chemical oxygen demand (COD), was 100% when modelled by both the Weibull and the lognormal distributions. The respective reliability values for total nitrogen removal were 76.8% and 77.0%, total suspended solids - 99.5% and 92.6%, and PO 4 -P - 98.2% and 95.2%, with the differences being negligible. The installation was characterized by a very high level of technological reliability when compared with other solutions of this type. The Weibull method employed for statistical evaluation of technological reliability can also be used for comparison purposes. From the ecological perspective, the facility presented in the study has proven to be an effective tool for protecting local aquifer areas.

Constructed wetlands and solar-driven disinfection technologies for sustainable wastewater treatment and reclamation in rural India: SWINGS project.

Science.gov (United States)

Álvarez, J A; Ávila, C; Otter, P; Kilian, R; Istenič, D; Rolletschek, M; Molle, P; Khalil, N; Ameršek, I; Mishra, V K; Jorgensen, C; Garfi, A; Carvalho, P; Brix, H; Arias, C A

2017-09-01

SWINGS was a cooperation project between the European Union and India, aiming at implementing state of the art low-cost technologies for the treatment and reuse of domestic wastewater in rural areas of India. The largest wastewater treatment plant consists of a high-rate anaerobic system, followed by vertical and horizontal subsurface flow constructed wetlands with a treatment area of around 1,900 m 2 and a final step consisting of solar-driven anodic oxidation (AO) and ultraviolet (UV) disinfection units allowing direct reuse of the treated water. The implementation and operation of two pilot plants in north (Aligarh Muslim University, AMU) and central India (Indira Gandhi National Tribal University, IGNTU) are shown in this study. The overall performance of AMU pilot plant during the first 7 months of operation showed organic matter removal efficiencies of 87% total suspended solids, 95% 5-day biological oxygen demand (BOD 5 ) and 90% chemical oxygen demand, while Kjeldahl nitrogen removal reached 89%. The UV disinfection unit produces water for irrigation and toilet flushing with pathogenic indicator bacteria well below WHO guidelines. On the other hand, the AO disinfection unit implemented at IGNTU and operated for almost a year has been shown to produce an effluent of sufficient quality to be reused by the local population for agriculture and irrigation.

Assessment of sulfide production risk in soil during the infiltration of domestic wastewater treated by a sulfur-utilizing denitrification process.

Science.gov (United States)

Ghorbel, L; Coudert, L; Gilbert, Y; Mercier, G; Blais, J F

2016-10-01

This study aimed to determine the potential of sulfide generation during infiltration through soil of domestic wastewater treated by a sulfur-utilizing denitrification process. Three types of soil with different permeability rates (K s = 0.028, 0.0013, and 0.00015 cm/s) were investigated to evaluate the potential risk of sulfur generation during the infiltration of domestic wastewater treated by a sulfur-utilizing denitrification system. These soils were thoroughly characterized and tested to assess their capacity to be used as drainages for wastewaters. Experiments were conducted under two operating modes (saturated and unsaturated). Sulfate, sulfide, and chemical oxygen demand (COD) levels were determined over a period of 100 days. Despite the high concentration of sulfates (200 mg/L) under anaerobic conditions (ORP = -297 mV), no significant amount of sulfide was generated in the aqueous (soil permeability did not have a noticeable effect on the infiltration of domestic wastewater treated by a sulfur-utilizing denitrification system due to low contents of organic matter (i.e., dissolved organic carbon, DOC). The autotrophic denitrification process used to treat the domestic wastewater allowed the reduction of the concentration of biochemical oxygen demand (BOD5) below 5 mg/L, of DOC below 7 mg/L, and of COD below 100 mg/L.

Effects of electric potential, NaCl, pH and distance between electrodes on efficiency of electrolysis in landfill leachate treatment.

Science.gov (United States)

Erabee, Iqbal K; Ahsan, Amimul; Jose, Bipin; Arunkumar, T; Sathyamurthy, R; Idrus, Syazwani; Daud, N N Nik

2017-07-03

This study investigated the effects of different parameters on the removal efficiencies of organic and inorganic pollutants in landfill leachate treatment by electrolysis. Different parameters were considered such as the electric potential (e.g., 24, 40 and 60 V), hydraulic retention time (HRT) (e.g., 40, 60, 80, 100 and 120 min), sodium chloride (NaCl) concentration (e.g., 1, 3, 5 and 7%), pH (e.g., 3, 7 and 9), electrodes materials [e.g., aluminum (Al) and iron (Fe)] and distance between electrodes (e.g., 1, 2 and 3 cm). The best operational condition of electrolysis was then recommended. The electric potential of 60 V with HRT of 120 min at 5% of NaCl solution using Al as anode and Fe as cathode (kept at a distance of 3 cm) was the most efficient condition which increased the removal efficiencies of various parameters such as turbidity, salinity, total suspended solids (TSS), total dissolved solids (TDS), biochemical oxygen demand (BOD), chemical oxygen demand (COD) and heavy metals (e.g., Zn and Mn). The higher removal percentages of many parameters, especially COD (94%) and Mn (93%) indicated that the electrolysis is an efficient technique for multi-pollutants (e.g., organic, inorganic and heavy metals) removal from the landfill leachate.

Feasibility of the UV/AA process as a pretreatment approach for bioremediation of dye-laden wastewater.

Science.gov (United States)

Yang, Minghui; Wu, Bingdang; Li, Qiuhao; Xiong, Xiaofeng; Zhang, Haoran; Tian, Yu; Xie, Jiawen; Huang, Ping; Tan, Suo; Wang, Guodong; Zhang, Li; Zhang, Shujuan

2018-03-01

Biodegradability and toxicity are two important indexes in considering the feasibility of a chemical process for environmental remediation. The acetylacetone (AA) mediated photochemical process has been proven as an efficient approach for dye decolorization. Both AA and its photochemical degradation products had a high bioavailability. However, the biocompatibility and ecotoxicology of the UV/AA treated solutions are unclear yet. In the present work, we evaluated the biocompatibility and toxicity of the UV/AA treated solutions at both biochemical and organismal levels. The biodegradability of the treated solution was evaluated with the ratio of 5-d biological oxygen demand (BOD 5 ) to chemical oxygen demand (COD) and a 28-d activated sludge assay (Zahn-Wellens tests). The UV/AA process significantly improved the biodegradability of the tested dye solutions. Toxicity was assessed with responses of microorganisms (microbes in activated sludge and Daphnia magna) and plants (bok choy, rice seed, and Arabidopsis thaliana) to the treated solutions, which showed that the toxicity of the UV/AA treated solutions was lower or comparable to that of the UV/H 2 O 2 counterparts. The results are helpful for us to determine whether the UV/AA process is applicable to certain wastewaters and how the UV/AA process could be effectively combined into a sequential chemical-biological water treatment. Copyright © 2017 Elsevier Ltd. All rights reserved.

Multiple antibiotic resistance patterns of rhizospheric bacteria isolated from Phragmites australis growing in constructed wetland for distillery effluent treatment.

Science.gov (United States)

Chaturvedi, Sonal; Chandra, Ram; Rai, Vibhuti

2008-01-01

Susceptibility patterns of 12 different antibiotics were investigated against rhizospheric bacteria isolated from Phragmites australis from three different zones i.e. upper (0-5 cm), middle (5-10 cm), lower (10-15 cm) in constructed wetland system with and without distillery effluent. The major pollutants of distillery effluent were phenols, sulphide, heavy metals, and higher levels of biological oxygen demand (BOD), chemical oxygen demand (COD) etc. The antibiotic resistance properties of bacteria were correlated with the heavy metal tolerance (one of distillery pollutant). Twenty-two species from contaminated and seventeen species from non-contaminated site were tested by agar disc-diffusion method. The results revealed that more than 63% of total isolates were resistance towards one or more antibiotics tested from all the three different zones of contaminated sites. The multiple-drug resistance property was shown by total 8 isolates from effluent contaminated region out of which 3 isolates were from upper zone, 3 isolates from middle zone and 2 isolates were from lower zone. Results indicated that isolates from contaminated rhizosphere were found more resistant to antibiotics than isolates from non-contaminated rhizosphere. Further this study produces evidence suggesting that tolerance to antibiotics was acquired by isolates for the adaptation and detoxification of all the pollutants present in the effluent at contaminated site. This consequently facilitated the phytoremediation of effluent, which emerges the tolerance and increases resistance to antibiotics.

Comparison of airline passenger oxygen systems.

Science.gov (United States)

Byrne, N J

1995-08-01

The principal sources of oxygen for inflight passenger use, scheduled and unscheduled, are examined. Present practices of assessment of the passenger's "fitness to fly" are described. Three partner airlines, British Airways, U.S. Air, and Qantas, catering for more than 8000 oxygen requests annually, are compared. Analysis of customer use suggests that medical oxygen requests are frequently not clinically justified. The growth in demand, for both scheduled and unscheduled use of an expensive resource, supports the need for a "recommended best practice" among carriers. Passengers with respiratory disorders who will most benefit from inflight oxygen are vulnerable either to hypoxia or asthma.

Remediation of a winery wastewater combining aerobic biological oxidation and electrochemical advanced oxidation processes.

Science.gov (United States)

Moreira, Francisca C; Boaventura, Rui A R; Brillas, Enric; Vilar, Vítor J P

2015-05-15

Apart from a high biodegradable fraction consisting of organic acids, sugars and alcohols, winery wastewaters exhibit a recalcitrant fraction containing high-molecular-weight compounds as polyphenols, tannins and lignins. In this context, a winery wastewater was firstly subjected to a biological oxidation to mineralize the biodegradable fraction and afterwards an electrochemical advanced oxidation process (EAOP) was applied in order to mineralize the refractory molecules or transform them into simpler ones that can be further biodegraded. The biological oxidation led to above 97% removals of dissolved organic carbon (DOC), chemical oxygen demand (COD) and 5-day biochemical oxygen demand (BOD5), but was inefficient on the degradation of a bioresistant fraction corresponding to 130 mg L(-1) of DOC, 380 mg O2 L(-1) of COD and 8.2 mg caffeic acid equivalent L(-1) of total dissolved polyphenols. Various EAOPs such as anodic oxidation with electrogenerated H2O2 (AO-H2O2), electro-Fenton (EF), UVA photoelectro-Fenton (PEF) and solar PEF (SPEF) were then applied to the recalcitrant effluent fraction using a 2.2 L lab-scale flow plant containing an electrochemical cell equipped with a boron-doped diamond (BDD) anode and a carbon-PTFE air-diffusion cathode and coupled to a photoreactor with compound parabolic collectors (CPCs). The influence of initial Fe(2+) concentration and current density on the PEF process was evaluated. The relative oxidative ability of EAOPs increased in the order AO-H2O2 < EF < PEF ≤ SPEF. The SPEF process using an initial Fe(2+) concentration of 35 mg L(-1), current density of 25 mA cm(-2), pH of 2.8 and 25 °C reached removals of 86% on DOC and 68% on COD after 240 min, regarding the biologically treated effluent, along with energy consumptions of 45 kWh (kg DOC)(-1) and 5.1 kWh m(-3). After this coupled treatment, color, odor, COD, BOD5, NH4(+), NO3(-) and SO4(2-) parameters complied with the legislation targets and, in addition, a total

Evaluation, prediction, and protection of water quality in Danjiangkou Reservoir, China

Directory of Open Access Journals (Sweden)

Xiao-kang Xin

2015-01-01

Full Text Available The water quality in the Danjiangkou Reservoir has attracted considerable attention from the Chinese public and government since the announcement of the Middle Route of the South to North Water Diversion Project (SNWDP, which commenced transferring water in 2014. Integrated research on the evaluation, prediction, and protection of water quality in the Danjiangkou Reservoir was carried out in this study in order to improve environmental management. Based on 120 water samples, wherein 17 water quality indices were measured at 20 monitoring sites, a single factor evaluation method was used to evaluate the current status of water quality. The results show that the main indices influencing the water quality in the Danjiangkou Reservoir are total phosphorus (TP, permanganate index (CODMn, dissolved oxygen (DO, and five-day biochemical oxygen demand (BOD5, and the concentrations of TP, BOD5, ammonia nitrogen (NH3–N, CODMn, DO, and anionic surfactant (Surfa do not reach the specified standard levels in the tributaries. Seasonal Mann–Kendall tests indicated that the CODMn concentration shows a highly significant increasing trend, and the TP concentration shows a significant increasing trend in the Danjiangkou Reservoir. The distribution of the main water quality indices in the Danjiangkou Reservoir was predicted using a two-dimensional water quality numerical model, and showed that the sphere of influence from the tributaries can spread across half of the Han Reservoir if the pollutants are not controlled. Cluster analysis (CA results suggest that the Shending River is heavily polluted, that the Jianghe, Sihe, and Jianhe rivers are moderately polluted, and that they should be the focus of environmental remediation.

Development of a down-flow hanging sponge reactor for the treatment of low strength sewage.

Science.gov (United States)

Yoochatchaval, Wilasinee; Onodera, Takashi; Sumino, Haruhiko; Yamaguchi, Takashi; Mizuochi, Motoyuki; Okadera, Tomohiro; Syutsubo, Kazuaki

2014-01-01

The process performance of a down-flow hanging sponge (DHS) reactor for treating low strength sewage (biochemical oxygen demand (BOD) 20-50 mg/L) was investigated in Bangkok, Thailand. The hydraulic retention time (HRT) was set at 4 h during the start-up period and was reduced to 1.5 h in a stepwise manner. Throughout the 300-day operational period, the DHS reactor shows high performance with respect to the removal of total suspended solid (>90% total suspended solid removal efficiency). No clogging of sponge media was observed in response to the self-digestion phenomena of the biofilm. At a HRT of 1.5 h, the BOD removal efficiency was sufficiently high (about 85%). The pathogen Escherichia coli and other coliform bacteria were removed almost completely as well (removal was 99.4% and 98.1%, respectively). Regarding the retained sludge activity measurement, the nitrite oxidation rate was higher than the ammonium oxidation rate (0.031 and 0.022 gram of nitrogen per gram of volatile suspended solids per day, respectively). In the 300 days of operation, the amount of excess sludge production was negligible. Thus, no sludge treatment system is required. Introduction of the DHS system in developing countries is recommended because this system requires a relatively small area, and has low electricity consumption and operation costs.

The indium-oxygen system, ch. 5

International Nuclear Information System (INIS)

Dillen, A.J. van

1977-01-01

This chapter is divided into three sections: 1) a survey of the literature concerning the indiumoxygen system, 2) the adsorption of oxygen at pure and partially oxidized indium surfaces in the temperature range 20-180degC, and 3) the oxidation of indium at temperatures above 180degC. The oxygen uptake is determined volumetrically and gravimetrically. The influence of the melting point is considered and the results are compared with data from the literature. The oxide layer is amorphous at lower temperatures but above 350degC, crystallisation of In 2 O 3 takes place

Oxygen vacancy as fatigue evidence of La0.5Sr0.5CoO3/PbZr0.4Ti0.6O3/La0.5Sr0.5CoO3 capacitors

Science.gov (United States)

Liu, B. T.; Chen, J. E.; Sun, J.; Wei, D. Y.; Chen, J. H.; Li, X. H.; Bian, F.; Zhou, Y.; Guo, J. X.; Zhao, Q. X.; Guan, L.; Wang, Y. L.; Guo, Q. L.; Ma, L. X.

2010-09-01

La0.5Sr0.5CoO3 (LSCO) films grown on SrTiO3 substrates, cooled at reduced oxygen pressures, ranging from 8×104 to 1×10-4 Pa, from the depostion temperature, are used as the bottom electrodes of PbZr0.4Ti0.6O3 (PZT) capacitors to study the impact of oxygen stoichiometry of the LSCO bottom electrodes on the structural and physical properties of LSCO/PZT/LSCO capacitors. It is found that the tetragonality, polarization and fatigue-resistance of PZT films decrease with the decrease of the cooling oxygen pressure. Almost 60% polarization degradation occurs for the PZT capacitor with the LSCO bottom electrode cooled in 1×10-4 Pa oxygen up to 1010 switching cycles, indicating that the oxygen vacancy of the bottom electrode can result in fatigue of the LSCO/PZT/LSCO capacitor.

Feasibility of on-site grey-water reuse for toilet flushing in China

Directory of Open Access Journals (Sweden)

Jie Zhu

2018-03-01

Full Text Available Although the total reuse rate of municipal wastewater was 8.8% in China in 2012, water crisis is forcing China to increasingly develop water reuse. Urban reuse is comparatively poor and has significant potential to be promoted in China. It is a sensitive matter whether to include kitchen wastewater in grey-water reuse in water-deficient areas when kitchen wastewater accounts for a large proportion of total domestic water consumption. Concentrations of chemical oxygen demand, BOD5 (biochemical oxygen demand, and total organic carbon in kitchen wastewater are comparatively lower in China than in other countries, but a high concentration of nitrogen from washing tableware and rice makes it difficult to meet nitrogen requirements in Chinese guidelines. Whether kitchen wastewater should be included in grey-water reuse in China needs further study. Aerobic biological processes combined with physical filtration and/or disinfection is preferred in grey-water treatment, and how to balance the investment and treatment costs with reuse criteria still needs to be researched further. The promotion of reclaimed water for toilet flushing faces resistance in China. The necessity and effectiveness of existing restrictions in water reuse guidelines for toilet flushing in China are in doubt and need further discussion.

Efficiency of a Horizontal Sub-Surface Flow Constructed Wetland Treatment System in an Arid Area

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Abeer Albalawneh

2016-02-01

Full Text Available The main objective of this study was to evaluate the performance and treatment efficiency of the Horizontal Sub-Surface Flow Constructed Wetland treatment system (HSF-CW in an arid climate. Seventeen sub-surface, horizontal-flow HSF-CW units have been operated for approximately three years to improve the quality of partially-treated municipal wastewater. The studied design parameters included two sizes of volcanic tuff media (i.e., fine or coarse, two different bed dimensions (i.e., long and short, and three plantation types (i.e., reed, kenaf, or no vegetation as a control. The effluent Biological Oxygen Demand (BOD5, Chemical Oxygen Demand (COD, Total Suspended Solid (TSS, and phosphorus from all of the treatments were significantly lower as compared to the influent and demonstrated a removal efficiency of 55%, 51%, 67%, and 55%, respectively. There were significant increases in Electrical Conductivity (EC, sulfate, and calcium in the effluent of most HSF-CWs due to evaporative concentration and mineral dissolution from the media. The study suggests that unplanted beds with either fine or coarse media are the most suitable combinations among all of the studied designs based on their treatment efficiency and less water loss in arid conditions.

The Effect of H2O2 Interference in Chemical Oxygen Demand Removal During Advanced Oxidation Processes

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Afsane Chavoshani

2016-07-01

Full Text Available Hydrogen peroxide (H2O2 is one of the most oxidants in AOPs. By H2O2 dissociation, hydroxyl radical with a standard oxidation potential of 2.7 is produced. It is reported H2O¬ residual in AOPs has been led to interference in chemical oxygen demand (COD test and it is able to hinder biological treatment of waste water. Because of high mixed organic load of solid waste leachate, this study investigated effect of H2O2 interference in COD removal from solid waste leachate. In this study effect of parameters such as pH (3,5,7,12, H2O2 dose (0.01, 0.02, 0.03, 0.04 mol l-1, and time reaction(10,20,30,40,50,60 min evaluated on H2O2 interference in COD removal from solid waste leachate. Optimum pH and concentration were 3 and 0.02 moll-1 respectively. With increasing reaction time, COD removal was increased. The false COD obtained between 0.49mg per 1mg of H2O2. The average of COD removal by H2O2 for 60 min was 6.57%. Also reaction rate of this process was 0.0029 min-1. The presence of H2O2 leads to overestimation of COD values after reaction time because it consumes the oxidation agent. The extent of H2O2 interference in COD analysis was proportional to the remaining H2O2 concentration at the moment of sampling.

Biological treatment of potato processing wastewater for red pigment production by immobilized cells of UV-irradiated monascus sp. in repeated batch

International Nuclear Information System (INIS)

Khalaf, S.A.

2004-01-01

Potato processing wastewater (PPW) was collected and analyzed for biological oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), total nitrogen and starch content. A fungal strain isolated from PPW identified as Monascus sp. PPW was evaluated for its ability to grow and produce red pigment, biomass and reduce the starch content of the ,PPW. Active UV-irradiated isolate of the above strain was obtained by exposing the parent strain to UV-radiation and coded Monascus. sp. PPW-UV7 and used as immobilized cell system for PPW treatment process in repeated batch fermentation. The immobilized cells (in sponge cubes) were able to reduce COD by about 85.7 %, with biomass production of 9.22 gl+ l and over productivity of red pigment of 2.6 gl+ 1 after 8 days fermentation (2 batches). The immobilized cells showed stability and viability for 8 batches (32 days) during the process treatment

Stensund wastewater aquaculture. Studies of key factors for its optimization

Energy Technology Data Exchange (ETDEWEB)

Guterstam, B.; Forsberg, L.E. [Stensund Ecological Center, Stensunds Fold Center, S-61991 Trosa (Sweden); Buczynska, A. [Faculty of Process and Environmental Engineering, Technical University of Lodz, 175 Wolczanska strasse, PL-90942 Lodz (Poland); Frelek, K. [Department of Analytical Chemistry, Medical University of Gdansk, Al. Gen. J. Hallera 107, PL-80416 Gdansk (Poland); Pilkaityte, R. [Natural Science Faculty, University of Klaipeda, LT-5813 Klaipeda (Lithuania); Reczek, L. [Department of Water Supply and Sewage Systems, Warsaw Agricultural University, 166 Nowoursynowska strasse, PL-02787 Warsaw (Poland); Rucevska, I. [Latvian Environmental Data Center, Straumes 2, Jurmala LV 2015 (Latvia)

1998-10-21

This paper is a summary of an in-depth study of key factors in the function of a 7-year-old aquaculture system designed for treatment and recycling of domestic wastewater at Stensund, Trosa, Sweden. The reported areas are: wastewater flows, reduction of biochemical oxygen demand (BOD), chemical oxygen demand (COD), phosphorus, nitrogen, and fecal bacteria. Plant production is recorded as harvested biomass, and energy results are given as generated heat and electricity consumption. Special studies were conducted on the reduction of copper by anaerobic treatment. Nitrification was studied with different filter media. Microalgal autofocculation of phosphorus was studied in relation to pH and water hardness for the green algal genus Scenedesmus. Limiting factors for the growth of Daphnia magna in the zooplankton step of the constructed aquatic food-web was studied in a specially designed reproduction test. The results are analyzed in order to optimize the function of the wastewater aquaculture

Pollution from tanneries effluents and its impact on environment

International Nuclear Information System (INIS)

Rajput, A.A.; Memon, Hafeez-ur-Rahman; Sahto, M.H.

1999-01-01

The disposal of tanneries effluence has become one of the serious environmental problems. The effluents from tanneries contain highly toxic materials, including chromium salts, ammonium salts, acids, sodium sulphide and suspended solids. Hair, alkalinity, surfactants, dyes and oils are also present in these effluents. The extent of pollution depends upon the volume of the effluent discharged. Many studies have been carried out on the characteristics of these effluents in order to understand the nature of the effluents and their impact on environment. The present study shows measured values of different parameters like Biochemical Oxygen Demand (BOD) about 1950 mg/l, Chemical Oxygen Demand (COD) about 4500-4600 mg/l, suspended solids about 2600-2700 mg/l, dissolved solids 10000-12000 mg/l and lead, copper, chromium and cadmium about 2, 0.4, 64.4 and 0.31 mg/l respectively. The measured values are compared with that of previous. Some remedial measures for its treatment and disposal are also discussed. (author)

Characterization and correlations of various pollution parameters in the tannery effluent

International Nuclear Information System (INIS)

Haydar, S.

2008-01-01

Wastewater characterization is an integral part of treatment and management strategies for industrial effluents. This paper outlines the results of detailed wastewater characterization studies conducted for a tannery in Sheikhupura, Punjab. The results of this study demonstrated that the composition of tannery wastewater could change continuously due to inherent nature of tannery operations. In general, tannery effluent was alkaline in nature and highly polluted in terms of organic, solids, sulfates, sulfides and chromium content. Basic ingredients of tannery effluent i.e. high alkalinity and substantial portions of BOD (Biochemical Oxygen Demand), COD (Chemical Oxygen Demand) and other pollutants in particulate form rendered it suitable for enhanced pollutant removals at primary stage of treatment using suitable coagulants. Results of primary treatment of wastewater from this tannery suggested that primary treatment alone was not capable of reducing pollutant loads significantly. Hence post-primary biological treatment was required to meet local effluent quality standards. (author)

Characterization and study of correlations among major pollution parameters in textile wastewater

International Nuclear Information System (INIS)

Hyder, S.; Bari, A.

2011-01-01

Wastewater characterization is an integral part of treatment and management strategies for industrial effluents. This paper outlines the results of detailed wastewater characterization studies conducted for a textile mill in Lahore, Punjab. The results of this study demonstrated that the composition of textile wastewater could change continuously due to inherent nature of textile operations. In general, textile wastewater was high in temperature and alkaline in nature. It was highly polluted in terms of solids and organic content. Most of the portion of solids and organic load was in the soluble form. On the basis of mean values, temperature, pH, TDS (Total Dissolved Solids), BOD (Biochemical Oxygen Demand) and COD (Chemical Oxygen Demand) were above the limits set by NEQS (National Environmental Quality Standards) while chlorides and sulfates were below the limits set by NEQS. Prior neutralization of wastewater with an acid and addition of phosphorus and nitrogen is imperative for its effective treatment. (author)

Characterization of Beauty Salon Wastewater from Kwame Nkrumah University of Science and Technology, Kumasi, Ghana, and Its Surrounding Communities.

Science.gov (United States)

Nkansah, Marian A; Opoku, Francis; Ephraim, James H; Wemegah, David D; Tetteh, Luke P M

2016-01-01

Due to the increase in students' population over the years, the Kwame Nkrumah University of Science and Technology (KNUST), Kumasi, Ghana, and its surrounding communities have seen an increase in the number of beauty salons. The assessment of the quality of salon wastewater has received little attention, as a potential source of environmental and public health hazard, due to the lack of literature on this issue. The main aim of this study is to assess wastewater effluent characteristics in KNUST and its surrounding areas, in relation to its physicochemical and microbial parameters. A total of 48 wastewater samples were collected monthly in 250 L polystyrene bottles, over a two-month period from the KNUST and Ayigya, Ayeduase, and Bomso communities. Standard methods of American Public Health Association (APHA, 19th edition) were employed in the determination of the physicochemical parameters and microbial content of the wastewater samples. The results showed that all the sampling towns had mean chemical oxygen demand (COD; 60.04 ± 1.82 mg/L), biological oxygen demand (BOD; 30.03 ± 9.11 mg/L), dissolved oxygen (DO; 3.00 ± 0.53 mg/L), pH (9.55 ± 0.42), nitrate (5.42 ± 0.36 mg/L), phosphate (23.61 ± 0.16 mg/L), acidity (1.70 ± 0.01 mg/L), alkalinity (70.88 ± 2.59 mg/L), turbidity (20.29 ± 3.86 NTU), electrical conductivity (EC; 1404.89 ± 114.11 μm/S), and total dissolved solids (TDS; 1150.25 ± 262.10 mg/L) in the salon waste. In the case of bacterial levels, pathogenic bacteria such as fecal coliforms, Escherichia coli, Shigella dysenteriae, and Salmonella enterica were absent, while the levels of Staphylococcus aureus and Pseudomonas aeruginosa did not pose any health risk. The correlation matrix showed a significant positive correlation between and among pH, alkalinity, TDS, and turbidity (P < 0.05). The results revealed that the wastewater collected from the salon effluents contain pollution indicator parameters such as EC, pH, PO4 (3-), BOD, and

RECENT PROGRESS OF OXYGEN/NITROGEN SEPARATION USING MEMBRANE TECHNOLOGY

OpenAIRE

K. C. CHONG; S. O. LAI; H. S. THIAM; H. C. TEOH; S. L. HENG

2016-01-01

The oxygen-enriched air is highly demanded for various industrial applications such as medical, chemical and enhanced combustion processes. The conventional oxygen/nitrogen production is either cryogenic distillation or pressure swing adsorption (PSA). Both of these techniques possess the production capability of 20 to 300 tonnes of oxygen per day and oxygen purity of more than 95%. However, these techniques are energy intensive. Alternatively, membrane technology is an emerging technology...

Using one filter stage of unsaturated/saturated vertical flow filters for nitrogen removal and footprint reduction of constructed wetlands.

Science.gov (United States)

Morvannou, Ania; Troesch, Stéphane; Esser, Dirk; Forquet, Nicolas; Petitjean, Alain; Molle, Pascal

2017-07-01

French vertical flow constructed wetlands (VFCW) treating raw wastewater have been developed successfully over the last 30 years. Nevertheless, the two-stage VFCWs require a total filtration area of 2-2.5 m 2 /P.E. Therefore, implementing a one-stage system in which treatment performances reach standard requirements is of interest. Biho-Filter ® is one of the solutions developed in France by Epur Nature. Biho-Filter ® is a vertical flow system with an unsaturated layer at the top and a saturated layer at the bottom. The aim of this study was to assess this new configuration and to optimize its design and operating conditions. The hydraulic functioning and pollutant removal efficiency of three different Biho-Filter ® plants commissioned between 2011 and 2012 were studied. Outlet concentrations of the most efficient Biho-Filter ® configuration are 70 mg/L, 15 mg/L, 15 mg/L and 25 mg/L for chemical oxygen demand (COD), 5-day biological oxygen demand (BOD 5 ), total suspended solids (TSS) and total Kjeldahl nitrogen (TKN), respectively. Up to 60% of total nitrogen is removed. Nitrification efficiency is mainly influenced by the height of the unsaturated zone and the recirculation rate. The optimum recirculation rate was found to be 100%. Denitrification in the saturated zone works at best with an influent COD/NO 3 -N ratio at the inflet of this zone larger than 2 and a hydraulic retention time longer than 0.75 days.

EFFECT OF TROUT PRODUCTION IN CONCRETE PONDS WITH A CASCADING FLOW OF WATER ON PHYSICAL AND CHEMICAL PROPERTY OF WATER

Directory of Open Access Journals (Sweden)

Marcin Sidoruk

2014-10-01

Full Text Available Fish rearing causes changes in water quality due to the use of feed, mineral and organic fertilizers, pharmaceuticals and disinfectants. Rational fishery management aims to maintain or restore the quality of water in natural ecosystems. Cultures produce a certain amount of waste and pollutants released into the environment with waters departing from ponds, but their harmfulness depends on the conditions and type of farming. Studies on the assessment of the effects of rearing trout on physical and chemical properties of surface water were carried out in 2010-2012. Were chosen trout farm located in the Pomeranian province about 36 miles southeast of Słupsk. Water samples for physical and chemical analysis were collected every two months (a total of 12 sets samples collected and labeled them: temperature [°C], dissolved oxygen [mg · dm-3], oxygen saturation [%] electrolytic conductivity [S · cm-1], pH, redox potential [mV] and BOD5 and CODCr. The study showed that the water used to supply breeding facilities meet the requirements to be met which are inland water salmonid habitat. Only periodically for BOD5 standards have been slightly exceeded. After passing through the joints deterioration of water quality did not cause a change in the quality of the class, if only temporarily BOD5 ratio were lower in its quality from the first to the third class.

Treatment of septic tank effluents by a full-scale capillary seepage soil biofiltration system.

Science.gov (United States)

Fan, Chihhao; Chang, Fang-Chih; Ko, Chun-Han; Teng, Chia-Ji; Chang, Tzi-Chin; Sheu, Yiong-Shing

2009-03-01

The purpose of this study is to evaluate the efficiency of septic tank effluent treatment by an underground capillary seepage soil biofiltration system in a suburban area of Taipei, Taiwan. In contrast to traditional subsurface wastewater infiltration systems, capillary seepage soil biofiltration systems initially draw incoming influent upwards from the distribution pipe by capillary and siphonage actions, then spread influent throughout the soil biofiltration bed. The underground capillary seepage soil biofiltration system consists of a train of underground treatment units, including one wastewater distribution tank, two capillary seepage soil biofiltration units in series, and a discharge tank. Each capillary seepage soil biofiltration unit contains one facultative digestion tank and one set of biofiltration beds. At the flow rate of 50 m3/day, average influent concentrations of biochemical oxygen demand (BOD), suspended solid (SS), ammonia nitrogen (NH3-N), and total phosphates (TP), were 36.15 mg/L, 29.14 mg/L, 16.05 mg/L, and 1.75 mg/L, respectively. After 1.5 years of system operation, the measured influent and effluent results show that the treatment efficiencies of the soil biofiltration system for BOD, SS, NH3-N, TP, and total coliforms are 82.96%, 60.95%, 67.17%, 74.86%, and 99.99%, respectively.