Bioaugmentation treatment of PV wafer manufacturing wastewater by microbial culture

The wastewater of silicon photovoltaic (PV) battery manufacturing contained polyethylene glycol (PEG) and detergents, which possessed the characteristics of high content of organics and low bioavailability, and then resulted in high treatment costs. To address the difficulties of existing treatment facilities in stably meeting discharge standards, eight tons of microbial culture (consisting of Bacillus sp. and Rhodococcus sp.) were added into the aerobic treatment unit. Subsequently, the effectiveness of the microbial culture in small-scale biological wastewater treatment was evaluated, and the operating conditions for engineering applications were optimized. The application study showed that the average chemical oxygen demand (COD) removal efficiency reached 95.0% when the pH value was 7, the gas–water ratio was 28:1, the reflux ratio was 50%, which indicated an increase of 51.2% contrasting with the situation without bioaugmentation. The volume load of the treatment facilities after augmentation increased by 127.9% and could tolerate the COD shock load reached 2,340 mg · L−1. At last, the effluence met the class I standard of the Integrated Wastewater Discharge Standard (GB8978–1996).

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Optimization of photo-Fenton process of RO concentrated coking wastewater using response surface methodology

Water Science & Technology ◽

10.2166/wst.2012.254 ◽

2012 ◽

Vol 66 (4) ◽

pp. 816-823 ◽

Cited By ~ 1

Author(s):

Zhang Huiqing ◽

Ye Chunsong ◽

Zhang Xian ◽

Yang Fan ◽

Yang Jun ◽

...

Keyword(s):

Response Surface Methodology ◽

Response Surface ◽

Ph Value ◽

Oxygen Demand ◽

Operating Conditions ◽

Quadratic Model ◽

Coking Wastewater ◽

Fenton Process ◽

Predicted Values ◽

Optimized Conditions

The objective of this study was aimed at investigating the removal of chemical oxygen demand (COD) from reverse osmosis (RO) concentrated coking wastewater by the photo-Fenton process. The optimum extraction conditions for the photo-Fenton process by Box–Behnken design (BBD) and response surface methodology (RSM) to establish a predictive polynomial quadratic model were discussed based on a single factor test. Optimized parameters validated by the analysis of variances (ANOVA) were found to be H2O2 concentration of 345.2 mg/L, pH value of 4.1 and reaction time of 103.5 minutes under ultraviolet irradiation. The experimental results of the COD removal under the optimized conditions presented better agreement with the predicted values with deviation error of 3.2%. The results confirmed that RSM based on BBD was a suitable method to optimize the operating conditions of RO concentrated coking wastewater.

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Development of a naturally derived coagulant for water and wastewater treatment

Water Science & Technology Water Supply ◽

10.2166/ws.2002.0155 ◽

2002 ◽

Vol 2 (5-6) ◽

pp. 89-94 ◽

Cited By ~ 4

Author(s):

G. Folkard ◽

J. Sutherland

Keyword(s):

Oxygen Demand ◽

Operating Conditions ◽

Water Soluble ◽

Upflow Anaerobic Sludge Blanket ◽

Anaerobic Sludge ◽

Seed Kernel ◽

Wet Season ◽

Water And Wastewater Treatment ◽

Treatment Unit ◽

Wide Range

Seeds of the pan tropical tree, Moringa oleifera Lam. (M. oleifera) contain water soluble, positively charged proteins that act as an effective coagulant (molecular weight 13 kDa and isoelectric pH 10-11). Treatment studies are reviewed using the extracts of the crushed seed kernel and of the presscake (solids residue remaining after oil extraction). M. oleifera seed was incorporated into a pilot scale treatment system as a primary coagulant to clarify river water of 400 NTU in the wet season. Over 90% turbidity removal was achieved in the sedimentation stage at a dosage of 100 mgL-1. The filtrate turbidity was maintained well below 5 NTU. Subsequent trials were conducted in an adjacent works operating at 60 m3h-1. Treatment performance was comparable to that of using aluminium sulphate. Inlet turbidities of 270-380 NTU were consistently reduced to below 4 NTU. A comprehensive study was undertaken to evaluate the potential of using M. oleifera coagulant within a contact flocculation filtration (CFF) pilot rig. A wide range of operating conditions was evaluated in order to establish the useful “working envelope” for this process combination (filtration rates 5-20 mh-1, initial turbidities 20-50 NTU). Principal results are presented. As a coagulant within chemically enhanced primary sedimentation (CEPS) of a mixed wastewater, M. oleifera dosed at 150 mgL-1 gave additional removals (compared to a plain sedimentation control) of 40% biochemical oxygen demand (BOD) and chemical oxygen demand (COD) and in excess of 80% for suspended solids (SS). Subsequent laboratory work coupled an upflow anaerobic sludge blanket reactor (UASB) to CEPS. M. oleifera coagulant in the CEPS pre-treatment unit beneficially increased the ratio of soluble COD to volatile SS by a factor of ten compared to plain sedimentation and by a factor of three when dosing ferric chloride. The UASB yielded more biogas and gave enhanced COD removal. Recent work on the extraction and purification of the active coagulant components is reviewed and the prospects for commercialisation are considered.

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Treatment of Sewage Using a Constructed Soil Rapid Infiltration System Combined with Pre-Denitrification

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph15092005 ◽

2018 ◽

Vol 15 (9) ◽

pp. 2005 ◽

Cited By ~ 1

Author(s):

Wenlai Xu ◽

Jinyao Chen ◽

Yue Jian ◽

Zhicheng Pan ◽

Zishen Mou

Keyword(s):

Carbon Source ◽

Removal Rate ◽

Oxygen Demand ◽

The Other ◽

Small Scale ◽

Reflux Ratio ◽

Activated Sludge Process ◽

Hydraulic Load ◽

Aerobic Nitrification ◽

Denitrification Process

The activated sludge process of the anaerobic/oxic (A/O) process has a good denitrification performance because it can make full use of the carbon source in the original sewage, and the denitrification can provide alkalinity for aerobic nitrification. The traditional constructed soil rapid infiltration (CSRI) system, on the other hand, has a poor nitrogen removal effect. Dividing the traditional CSRI system into two sections, one performs denitrification as an anoxic section, while the other performs nitrification as an aerobic section and is placed after the anoxic section. The nitrification liquid of the effluent from the aerobic section is mixed with the original wastewater and enters the anoxic section for denitrification. We expected that this would be improved by combining CSRI with a pre-denitrification step that would make full use of the carbon source in the original sewage. In a small-scale experimental model, the removal efficiencies of nitrogen, in the form of ammonium, nitrate, and total nitrogen (TN), as well as chemical oxygen demand (COD), were determined. The hydraulic load was varied, while the backflow reflux capacity was kept constant, to determine the effect on the pre-denitrification process. An average removal rate of 95.4% for NH4+-N and 96% for COD could be obtained when a hydraulic load of 80 cm3(cm2·d)−1 and a reflux ratio of 75% were applied. Under these conditions, the average removal rate of TN was 77.4%, which is much higher than what can be typically achieved with conventional CSRI systems.

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Treatment of Pharmaceutical Wastewater by Micro-Electrolysis and Fenton Oxidation Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.356-360.1622 ◽

2011 ◽

Vol 356-360 ◽

pp. 1622-1625 ◽

Cited By ~ 1

Author(s):

Chong Hao Huang ◽

Meng Xing Cao ◽

Jun Hong Luo ◽

Chao Zhang

Keyword(s):

Reaction Time ◽

Oxidation Process ◽

Ph Value ◽

Oxygen Demand ◽

Operating Conditions ◽

Fenton Process ◽

Mass Ratio ◽

Pharmaceutical Wastewater ◽

Initial Ph ◽

Fenton Oxidation Process

Pharmaceutical wastewater was treated by micro-electrolysis and Fenton process.The aim of this research was to optimize operating parameters in micro-electrolysis and Fenton process. Effectiveness of important process parameters such as mass ratio of iron to carbon, the initial pH, reaction time and H2O2 dosage on the performance of micro-electrolysis and Fenton process were investigated. The results show that the removal efficiency of pharmaceutical wastewater chemical oxygen demand (COD) could reach 37.3% at the optimal pH of 4 with the iron to carbon ratio of 1:1 after 80 min treatment. The operating conditions of Fenton process are 0.5% of H2O2 dosage, the pH value of 4 and the reaction time of 180 min. The pharmaceutical wastewater COD removal could reach 79.4%.

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Assessment of an Integrated and Sustainable Multistage System for the Treatment of Poultry Slaughterhouse Wastewater

Membranes ◽

10.3390/membranes11080582 ◽

2021 ◽

Vol 11 (8) ◽

pp. 582

Author(s):

Phumeza Akhona Dyosile ◽

Cebisa Mdladla ◽

Mahomet Njoya ◽

Moses Basitere ◽

Seteno Karabo Obed Ntwampe ◽

...

Keyword(s):

Oxygen Demand ◽

Membrane System ◽

Operating Conditions ◽

Oil And Grease ◽

Treatment Unit ◽

Slaughterhouse Wastewater ◽

Multistage System ◽

Pre Treatment ◽

Set Up ◽

Lipid Reduction

This paper assesses the performance of an integrated multistage laboratory-scale plant, for the treatment of poultry slaughterhouse wastewater (PSW). The system was comprised of an eco-flush dosed bio-physico pre-treatment unit for fats, oil, and grease (FOG) hydrolysis prior to the PSW being fed to a down-flow expanded granular bed reactor (DEGBR), coupled to a membrane bioreactor (DEGBR-MBR). The system’s configuration strategy was developed to achieve optimal PSW treatment by introducing the enzymatic pre-treatment unit for the lipid-rich influent (PSW) in order to treat FOG including odour causing constituents such as H2S known to sour anaerobic digestion (AD) such that the PSW pollutant load is alleviated prior to AD treatment. This was conducted to aid the reduction in clogging and sludge washout in the DEGBR-MBR systems and to achieve the optimum reactor and membrane system performance. A performance for the treatment of PSW after lipid reduction was conducted through a qualitative analysis by assessing the pre- and post-pre-treatment units’ chemical oxygen demand (COD), total suspended solids (TSS), and FOG concentrations across all other units and, in particular, the membrane units. Furthermore, a similar set-up and operating conditions in a comparative study was also performed. The pre-treatment unit’s biodelipidation abilities were characterised by a mean FOG removal of 80% and the TSS and COD removal reached 38 and 56%, respectively. The final acquired removal results on the DEGBR, at an OLR of ~18–45 g COD/L.d, was 87, 93, and 90% for COD, TSS, and FOG, respectively. The total removal efficiency across the pre-treatment-DEGBR-MBR units was 99% for COD, TSS, and FOG. Even at a high OLR, the pre-treatment-DEGBR-MBR train seemed a robust treatment strategy and achieved the effluent quality set requirements for effluent discharge in most countries.

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Treatment of wastewater contaminated with detergents and mineral oils using effective and scalable technology

Water Science & Technology ◽

10.2166/wst.2013.275 ◽

2013 ◽

Vol 68 (5) ◽

pp. 974-981 ◽

Cited By ~ 3

Author(s):

Wael Abdelmoez ◽

Nasser A. M. Barakat ◽

Asmaa Moaz

Keyword(s):

Treatment Process ◽

Ph Value ◽

Oxygen Demand ◽

Operating Conditions ◽

Solid Particles ◽

Treated Wastewater ◽

Oily Wastewater ◽

Mineral Oils ◽

Car Wash ◽

Carbon Filtration

In this work, effective, cheap and scalable methodology is introduced to treat oily wastewater. The water produced from car-wash processes was utilized as a model because it has various pollutants – oil, lubricants, detergents, solid particles, etc. The results showed that the turbidity and chemical oxygen demand (COD) values dramatically decrease by using the proposed treatment process, which consists of coagulation, flocculation, sand filtration, and oxidation followed by sand as well as activated carbon filtration. Moreover, the operating conditions were optimized. Without adjustment of the pH value of car-wash wastewater, it was found that 200 ppm of ferric chloride, as a coagulant, and 1 ppm of potassium permanganate, as an oxidant, are the optimum doses. The COD and turbidity values of the final treated wastewater were reduced by almost 88 and 100%, respectively. A prototype with 15 L capacity was designed and fabricated to investigate the scaling up and continuity of the proposed treatment strategy. The results were very promising and indicated that the introduced methodology can be industrially applied.

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Validation of On-line Respiration Meter and its Applications by Computer Simulation

Water Science & Technology ◽

10.2166/wst.1992.0578 ◽

1992 ◽

Vol 26 (5-6) ◽

pp. 1355-1363 ◽

Cited By ~ 2

Author(s):

C-W. Kim ◽

H. Spanjers ◽

A. Klapwijk

Keyword(s):

Steady State ◽

Activated Sludge ◽

Respiration Rate ◽

Oxygen Demand ◽

Operating Conditions ◽

Mass Balances ◽

Short Term ◽

Respiration Rates ◽

On Line ◽

Made In

An on-line respiration meter is presented to monitor three types of respiration rates of activated sludge and to calculate effluent and influent short term biochemical oxygen demand (BODst) in the continuous activated sludge process. This work is to verify if the calculated BODst is reliable and the assumptions made in the course of developing the proposed procedure were acceptable. A mathematical model and a dynamic simulation program are written for an activated sludge model plant along with the respiration meter based on mass balances of BODst and DO. The simulation results show that the three types of respiration rate reach steady state within 15 minutes under reasonable operating conditions. As long as the respiration rate reaches steady state the proposed procedure calculates the respiration rate that is equal to the simulated. Under constant and dynamic BODst loading, the proposed procedure is capable of calculating the effluent and influent BODst with reasonable accuracy.

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Treatment of fish processing industry wastewater using hydrodynamic cavitational reactor with biodegradability improvement

Water Science & Technology ◽

10.2166/wst.2020.049 ◽

2019 ◽

Vol 80 (12) ◽

pp. 2310-2319 ◽

Cited By ~ 2

Author(s):

Prashant Dhanke ◽

Sameer Wagh ◽

Abhijeet Patil

Keyword(s):

Organic Matter ◽

New Technology ◽

Oxygen Demand ◽

Operating Conditions ◽

Hydrodynamic Cavitation ◽

Inlet Pressure ◽

Fish Processing ◽

Processing Industry ◽

Cavitation Effect ◽

Processing Plants

Abstract Water generated from the fish processing industry is contaminated with organic matter. This organic matter present in wastewater increases the biochemical oxygen demand (BOD) and chemical oxygen demand (COD). A new technology, hydrodynamic cavitation (HC) is used to deal with this wastewater produced in fish processing plants. The orifice plate is used in the HC reactor to generate a cavitation effect. The intensification of this technique was carried out with the help of hydrogen peroxide (H2O2) and TiO2. The treatment of this wastewater is reported in terms of percent degradation in BOD and COD and in biodegradability index (BI). Operating parameters like inlet pressure, pH, operating temperature and H2O2 doses were used to find the optimum condition. 15 g/L of H2O2 gave 69.5% reduction of COD in the 120 min of treatment that also increases BI value to 0.93 at inlet pressure 8 bar, Plate-5, temperature (30 °C), and pH 4. In the ultrasonic cavitation (UC) reactor, COD reduction is 68.7% without TiO2 and with TiO2 it is 71.2%. Also, this HC and UC reactor reduced CFU count to a great extent at the same operating conditions.

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Effective Chromium Adsorption From Aqueous Solutions and Tannery Wastewater Using Bimetallic Fe/Cu Nanoparticles: Response Surface Methodology and Artificial Neural Network

Air Soil and Water Research ◽

10.1177/11786221211028162 ◽

2021 ◽

Vol 14 ◽

pp. 117862212110281

Author(s):

Ahmed S. Mahmoud ◽

Nouran Y. Mohamed ◽

Mohamed K. Mostafa ◽

Mohamed S. Mahmoud

Keyword(s):

Response Surface Methodology ◽

Response Surface ◽

Industrial Effluent ◽

Oxygen Demand ◽

Operating Conditions ◽

Tannery Wastewater ◽

P Value ◽

Cu Nanoparticles ◽

Artificial Neural ◽

Cr Removal

Tannery industrial effluent is one of the most difficult wastewater types since it contains a huge concentration of organic, oil, and chrome (Cr). This study successfully prepared and applied bimetallic Fe/Cu nanoparticles (Fe/Cu NPs) for chrome removal. In the beginning, the Fe/Cu NPs was equilibrated by pure aqueous chrome solution at different operating conditions (lab scale), then the nanomaterial was applied in semi full scale. The operating conditions indicated that Fe/Cu NPs was able to adsorb 68% and 33% of Cr for initial concentrations of 1 and 9 mg/L, respectively. The removal occurred at pH 3 using 0.6 g/L Fe/Cu dose, stirring rate 200 r/min, contact time 20 min, and constant temperature 20 ± 2ºC. Adsorption isotherm proved that the Khan model is the most appropriate model for Cr removal using Fe/Cu NPs with the minimum error sum of 0.199. According to khan, the maximum uptakes was 20.5 mg/g Cr. Kinetic results proved that Pseudo Second Order mechanism with the least possible error of 0.098 indicated that the adsorption mechanism is chemisorption. Response surface methodology (RSM) equation was developed with a significant p-value = 0 to label the relations between Cr removal and different experimental parameters. Artificial neural networks (ANNs) were performed with a structure of 5-4-1 and the achieved results indicated that the effect of the dose is the most dominated variable for Cr removal. Application of Fe/Cu NPs in real tannery wastewater showed its ability to degrade and disinfect organic and biological contaminants in addition to chrome adsorption. The reduction in chemical oxygen demand (COD), biological oxygen demand (BOD), total suspended solids (TSS), total phosphorus (TP), total nitrogen (TN), Cr, hydrogen sulfide (H2S), and oil reached 61.5%, 49.5%, 44.8%, 100%, 38.9%, 96.3%, 88.7%, and 29.4%, respectively.

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Study on Chromaticity Removal from Mineral Processing Wastewater with Salicylic Hydroxamic Acid by Granular Activated Carbon Catalyzed Ozonation

Minerals ◽

10.3390/min11040359 ◽

2021 ◽

Vol 11 (4) ◽

pp. 359

Author(s):

Liping Zhang ◽

Shengnian Wu ◽

Nan Zhang ◽

Ruihan Yao ◽

Eryong Wu

Keyword(s):

Activated Carbon ◽

Reaction Time ◽

Hydroxamic Acid ◽

Ph Value ◽

Oxygen Demand ◽

Granular Activated Carbon ◽

Mineral Processing ◽

Ultraviolet Absorption Spectrum ◽

Experimental Conditions ◽

Removal Ratio

Salicylic hydroxamic acid is a novel flotation reagent used in mineral processing. However, it impacts the flotation wastewater leaving behind high chromaticity which limits its reuse and affects discharge for mining enterprises. This study researched ozonation catalyzed by the granular activated carbon (GAC) method to treat the chromaticity of the simulated mineral processing wastewater with salicylic hydroxamic acid. The effects of pH value, ozone (O3) concentration, GAC dosage, and reaction time on chromaticity and chemical oxygen demand (CODCr) removal were discussed. The results of individual ozonation experiments showed that the chromaticity removal ratio reached 79% and the effluent chromaticity exceeded the requirement of reuse and discharge when the optimal experimental conditions were pH value 3, ozone concentration 6 mg/L, and reaction time 40 min. The orthogonal experimental results of catalytic ozonation with GAC on chromaticity removal explained that the chromaticity removal ratio could reach 96.36% and the chromaticity of effluent was only 20 when the optimal level of experimental parameters was pH value 2.87, O3 concentration 6 mg/L, GAC dosage 0.06 g/L, reaction time 60 min respectively. The degradation pathway of salicylic hydroxamic acid by ozonation was also considered based on an analysis with ultraviolet absorption spectrum and high-performance liquid chromatography (HPLC).

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