Wastewater containing Cr(VI) treatment using solar tubular reactor

2016 ◽  
Vol 74 (7) ◽  
pp. 1698-1705 ◽  
Author(s):  
Tiele Caprioli Machado ◽  
Marla Azário Lansarin
Keyword(s):  
High Efficiency ◽  
Batch Reactor ◽  
Tubular Reactor ◽  
Pilot Scale ◽  
Specific Reaction Rate ◽  
Photochemical Reduction ◽  
Experimental Conditions ◽  
Environmentally Sustainable ◽  
Real Wastewater ◽  
Electroplating Process

The hexavalent chromium, Cr(VI), which is generated in the electroplating process, is toxic to most organisms and potentially harmful to human health. The method generally used for remediation of wastewater containing Cr(VI) employs chemicals with high toxicity. This work proposes an alternative technology for the treatment of these wastewaters, based on photochemical reduction of Cr(VI) by alcohols under radiation, which is environmentally sustainable and economically viable. Initially, a batch reactor in laboratory scale was used to determine the best experimental conditions and its specific reaction rate was calculated. Based on these results, a tubular reactor (artificial radiation and sunlight) was designed and built in semi-pilot scale. Tests were carried out with real wastewater from an electroplating industry containing Cr(VI). Tests conducted under sunlight showed a higher total Cr(VI) reduction than the tests with artificial radiation. The remediation of Cr(VI) from wastewater was 86.7% after 6 h of reaction under sunlight, indicating the high efficiency of the developed process.

A pilot scale study of a sequencing batch reactor treating municipal wastewater operated via the UP-PND process

2008 ◽  
Vol 58 (2) ◽  
pp. 435-438 ◽  
Author(s):  
M. Kornaros ◽  
C. Marazioti ◽  
G. Lyberatos
Keyword(s):  
Wastewater Treatment ◽  
Municipal Wastewater ◽  
Batch Reactor ◽  
Treatment Plant ◽  
Pilot Scale ◽  
Treated Wastewater ◽  
Synthetic Wastewater ◽  
Second Step ◽  
Decentralized Wastewater Treatment ◽  
Real Wastewater

SBRs are usually preferred as small and decentralized wastewater treatment systems. We have demonstrated previously that using a frequent enough switching between aerobic and anoxic conditions and a specific to the treated wastewater aerobic to anoxic phase ratio, it is possible to by-pass the second step of nitrification (i.e. conversion of nitrite to nitrate nitrogen). This innovative process for nitrate by-pass has been branded as UP-PND (University of Patras-Partial Nitrification Denitrification) (WO 2006/129132). The proved methodology was successfully transferred from a lab-scale SBR reactor treating synthetic wastewater to a pilot-scale SBR system treating real wastewater. In this work we present the results from the operation of this pilot-scale SBR, constructed in the Wastewater Treatment Plant of Patras (Greece), using 6-hour, 8-hour and 12-hour cycles. It is demonstrated that three pairs of aerobic/anoxic phases with a relative duration of 1:2 (8-hour cycle) and 2:3 (12-hour cycle) secures the desired by-pass of nitrate production.

Efficient treatment of dairy processing wastewater in a pilot scale Intermittently Aerated Sequencing Batch Reactor (IASBR)

2018 ◽  
Vol 85 (3) ◽  
pp. 384-387 ◽  
Author(s):  
Peter Leonard ◽  
William Finnegan ◽  
Maria Barrett ◽  
Xinmin Zhan
Keyword(s):  
Retention Time ◽  
Sequencing Batch Reactor ◽  
High Efficiency ◽  
Batch Reactor ◽  
Pilot Scale ◽  
Laboratory Scale ◽  
Aeration Tank ◽  
Efficient Treatment ◽  
Dairy Processing ◽  
Working Volume

This Research Communication describes the initial operation of a pilot-scale intermittently aerated sequencing batch reactor system, which is located at an Irish dairy processing factory. Laboratory-scale research has facilitated the design specifications and operational parameters necessary for the construction and running of a pilot-scale. Laboratory scale research was necessary prior to the pilot scale system to ensure high quality treatment and nutrient removal efficiencies. The pilot system operates with a hydraulic retention time of 4 d, a solids retention time of 16 d and a cycle length of 12 hours. There are 4 non-aeration and aeration phases within the system's react phase. This system has a 3000 l working volume, treating 375 l of wastewater per cycle, 750 l daily. The system was seeded from an aeration tank at the dairy processing factory where the unit is located. The system is operating with the goal to remove both nitrogen and phosphorus from the wastewater biologically, reducing the need for chemical treatment. Currently, the system is performing with high efficiency, treating the wastewater to an acceptable level according to the Irish Environmental Protection Agency for discharge into surrounding water bodies. Therefore, the initial removal results demonstrate this technology's suitability for the treatment of high strength dairy wastewaters.

Development and validation of a simplified model for the anaerobic degradation of phenol

2009 ◽  
Vol 60 (1) ◽  
pp. 37-45
Author(s):  
A. Donoso-Bravo ◽  
F. Rosenkranz ◽  
G. Ruiz-Filippi ◽  
R. Chamy
Keyword(s):  
Batch Reactor ◽  
Pilot Scale ◽  
Anaerobic Treatment ◽  
Simplified Model ◽  
Experimental Conditions ◽  
Operational Strategies ◽  
Industrial Plants ◽  
General Terms ◽  
Phenolic Wastewater ◽  
Development And Validation

The anaerobic treatment of phenolic wastewater has demonstrated to be a suitable biological system, for that reason, a large number of systems have been implemented in a lab/pilot scale, several industrial plants have also been developed. Despite of this, there is a lack of modeling applications within these systems. In order to enhance the anaerobic treatment of this kind of water, a simplified model of 2 populations and 3 reactions was developed and implemented. The parameter calibration and the model validation were carried out with experimental data obtained from an Anaerobic Sequencing Batch Reactor treating phenolic wastewater through two different operational strategies: sequential batches with a co-substrate and sequential fed-batches without a co-substrate. The model predicted the reactors performance accurately for the different experimental conditions tested. Therefore, the theoretical basis of the model is, in general terms, valid, and its utilization to predict the reactors performance or in control purposes is feasible.

scholarly journals Evaluation of an environmentally sustainable UV-assisted water treatment system for the removal of Bacillus globigii spores in water

2017 ◽  
Vol 18 (3) ◽  
pp. 968-975
Author(s):  
R. G. Silva ◽  
J. Szabo ◽  
V. Namboodiri ◽  
E. R. Krishnan ◽  
J. Rodriguez ◽  
...  
Keyword(s):  
Water Treatment ◽  
High Efficiency ◽  
Membrane Filter ◽  
Water Security ◽  
Disinfection Byproducts ◽  
Treatment System ◽  
Health Concern ◽  
Environmentally Sustainable ◽  
Inorganic Substances ◽  
The Impact

Abstract Development of greener water treatment technologies is important for the production of safe drinking water and water security applications, such as decontamination. Chlorine assisted disinfection is common and economical, but can generate disinfection byproducts (DBPs) that may be of health concern. DBPs are formed due to the reaction of chlorine with naturally occurring organic and inorganic substances in water. Currently, various innovative technologies are being developed as alternative approaches for preventing DBPs during water treatment. In this study, we evaluated the effectiveness of a novel combination of high efficiency flow filtration and UV disinfection treatment system for the removal of Bacillus globigii (B. globigii) spores in water. The filtration system consists of a charged membrane filter (CMF) that not only helps to remove suspended particles but also reduces the impact of other impurities including bio organisms. In order to get most performance details, the CMF was evaluated at clean, half-life, and end of life (EOL) conditions along with 100% UV transmittance (UVT). In addition, the effectiveness of the UV system was evaluated as a stand alone system at 100% and 70% EOL intensity. The study was conducted at the US EPA's Test and Evaluation (T&E) Facility in Cincinnati, OH, using B. globigii, a surrogate for B. anthracis spores. This non-chemical environmentally-friendly CMF/UV combination system and the stand alone UV unit showed greater than 6.0 log removal of B. globigii during the tests.

High-angle Kikuchi patterns

1954 ◽  
Vol 221 (1145) ◽  
pp. 224-242 ◽  
Keyword(s):  
Lithium Fluoride ◽  
High Efficiency ◽  
Cylindrical Specimen ◽  
Angle Of Incidence ◽  
High Angle ◽  
Lead Sulphide ◽  
Marked Contrast ◽  
Experimental Conditions ◽  
Low Intensity ◽  
Glancing Angle

A cylindrical specimen chamber and camera have been used to study the high-angle Kikuchi patterns obtained by reflexion of electrons, of energy 6 to 50 keV, from the cleavage surfaces of crystals with the sodium chloride structure. Angles of scattering ranging from 0 to 164° were covered. The relative intensity of the pattern at different scattering angles was measured using a photographic technique. The intensity distribution was found to become less steep as the energy of the incident electrons decreased. In photographs taken with a large value of the glancing angle of incidence, defect bands were found, starting near the shadow edge of the pattern; these changed to excess bands at higher angles of scattering. The most striking feature of the results is the remarkable intensity and clarity at the highest scattering angles of the pattern produced by crystals such as lead sulphide and potassium iodide, the constituents of which have a relatively high elastic scattering cross-section. In marked contrast, a relatively low intensity and low clarity was found at these angles for lithium fluoride under the same experimental conditions. An investigation of the width of Kikuchi bands, visible over the whole available angular range, showed that the electrons forming these bands had the same energy as that of the incident electrons within the experimental error of 10%. A possible mechanism is discussed by means of which electrons can be diffused through large angles with high efficiency, relative to small angles, and with relatively little loss of energy.

scholarly journals Post-treatment of tannery wastewater using pilot scale horizontal subsurface flow constructed wetlands (polishing)

2017 ◽  
Vol 77 (4) ◽  
pp. 988-998 ◽  
Author(s):  
Tadesse Alemu ◽  
Andualem Mekonnen ◽  
Seyoum Leta
Keyword(s):  
Removal Efficiency ◽  
Batch Reactor ◽  
Subsurface Flow ◽  
Oxygen Demand ◽  
Pilot Scale ◽  
Surface Flow ◽  
Tannery Wastewater ◽  
Treated Effluent ◽  
Horizontal Subsurface Flow ◽  
Pollutants Removal

Abstract In the present study, a pilot scale horizontal subsurface flow constructed wetland (CW) system planted with Phragmites karka; longitudinal profile was studied. The wetland was fed with tannery wastewater, pretreated in a two-stage anaerobic digester followed by a sequence batch reactor. Samples from each CW were taken and analyzed using standard methods. The removal efficiency of the CW system in terms of biological oxygen demand (BOD), chemical oxygen demand (COD), Cr and total coliforms were 91.3%, 90%, 97.3% and 99%, respectively. The removal efficiency for TN, NO3− and NH4+-N were 77.7%, 66.3% and 67.7%, respectively. Similarly, the removal efficiency of SO42−, S2− and total suspended solids (TSS) were 71.8%, 88.7% and 81.2%, respectively. The concentration of COD, BOD, TN, NO3−N, NH4+-N, SO42 and S2− in the final treated effluent were 113.2 ± 52, 56 ± 18, 49.3 ± 13, 22.75 ± 20, 17.1 ± 6.75, 88 ± 120 and 0.4 ± 0.44 mg/L, respectively. Pollutants removal was decreased in the first 12 m and increased along the CW cells. P. karka development in the first cell of CW was poor, small in size and experiencing chlorosis, but clogging was higher in this area due to high organic matter settling, causing a partial surface flow. The performance of the pilot CW as a tertiary treatment showed that the effluent meets the permissible discharge standards.

Wastewater nitrogen removal in SBRs, applying a step-feed strategy: from lab-scale to pilot-plant operation

2004 ◽  
Vol 50 (10) ◽  
pp. 89-96 ◽  
Author(s):  
S. Puig ◽  
M.T. Vives ◽  
Ll. Corominas ◽  
M.D. Balaguer ◽  
J. Colprim
Keyword(s):  
Organic Matter ◽  
Nitrogen Removal ◽  
Pilot Plant ◽  
Batch Reactor ◽  
Aerobic Oxidation ◽  
Scaling Up ◽  
Plant Operation ◽  
Feed Strategy ◽  
Real Wastewater ◽  
Biodegradable Organic Matter

One of the problems of nitrogen removal from wastewater when applying sequencing batch reactor (SBR) technology, is the specific use of organic matter for denitrification purposes. Since easily biodegradable organic matter is rapidly consumed under aerobic or anoxic conditions (i.e. aerobic oxidation or anoxic denitrification, respectively), it is an important factor to consider when scaling up SBRs from the laboratory to real plant operation. In this paper, we present the results obtained in relation to scaling up reactors from lab-scale to pilot-plant scale, treating real wastewater from two different locations: the laboratory and in situ, respectively. In order to make using easily biodegradable organic matter more efficient, the filling phases of SBR cycles were adjusted according to a step-feed strategy composed of 6 anoxic-aerobic events. Feeding only occurred during anoxic phases. The results obtained demonstrated that the methodology may be useful in treating real wastewater with high carbon and nitrogen variations, as it always kept effluent levels lower than the official standards require (effluent total COD lower than 125 mg COD/L and effluent Total Nitrogen lower than 15 mg N/L).

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