Removing high concentration of nickel (II) ions from synthetic wastewater by an indigenous microalgae consortium with a Revolving Algal Biofilm (RAB) system

This study compared the growth of the microalgae Scenedesmus dimorphus in synthetic wastewater and actual wastewater under different cultivation conditions, in terms of nitrogen and phosphorus availability, wastewater quality, light condition and CO2 addition. The results show that the form of nitrogen source had a significant effect on the growth of microalgae. Urea as a nitrogen source increased the growth rate of S. dimorphus significantly, while the high concentration of inorganic nitrogen inhibited the growth. When phosphate was 4 mg/L and pH was 7, the growth of S. dimorphus was the greatest. The bacteria in actual wastewater not only promote the growth of microalgae but also facilitate the formation of flocs, which is conducive to biomass harvest. With the increase in light intensity and light duration, S. dimorphus showed primarily an increasing and then a decreasing trend. Higher light intensity was required in actual wastewater than in synthetic wastewater, which may be due to the barrier effect of wastewater turbidity. S. dimorphus grew well in both kinds of wastewater with the addition of 2% CO2.

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Effect of 1,1,2,2-Tetrachloroethane on the Performance of Upflow Anaerobic Sludge Bed (UASB) Reactors

Water Science & Technology ◽

10.2166/wst.1999.0409 ◽

1999 ◽

Vol 40 (8) ◽

pp. 153-159

Author(s):

M. Navarrete ◽

N. Rodríguez ◽

R. Amils ◽

J. L. Sanz

Keyword(s):

Anaerobic Digestion ◽

Environmental Pollutants ◽

Chlorinated Hydrocarbons ◽

Granular Sludge ◽

Synthetic Wastewater ◽

Anaerobic Sludge ◽

High Concentration ◽

Chlorinated Aliphatic Hydrocarbons ◽

Industrial Wastewaters ◽

Uasb Reactors

Chlorinated aliphatic hydrocarbons (CAH) are important environmental pollutants since they are industrially used for a wide variety of applications. Chlorinated hydrocarbons are cited as important contributors to the inhibition of anaerobic digestion. In this work, the effect of 1,1,2,2-tetrachloroethane (TCE) on the performance of upflow anaerobic sludge bed (UASB) reactors fed with sucrose synthetic wastewater has been studied. According to the results obtained it can be concluded the possibility to use UASB reactors with granular sludge to treat industrial wastewaters with a continuous content of TCE up to a concentration of 130 mg/l or with incidental punctual discharges of high concentration of the toxicant up to 400 mg/l. In all cases in which the activity of the reactor was inhibited a fast recuperation was observed.

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EFFECTIVE REMOVAL OF TEXTILE DYES USING PRE-TREATED NATURAL ADSORBENTS

Environmental Contaminants Reviews ◽

10.26480/ecr.01.2021.19.23 ◽

2020 ◽

Vol 4 (1) ◽

pp. 19-23

Author(s):

Ch. Arslan ◽

Muhammad Hasnain ◽

Waheed Tariq

Keyword(s):

Sugarcane Bagasse ◽

Azo Dyes ◽

Water Contamination ◽

Synthetic Wastewater ◽

Modern World ◽

High Concentration ◽

Natural Adsorbents ◽

Direct Blue ◽

Effective Removal ◽

Chicken Eggshell

Water contamination due to textile industrial discharge is one of major problems of modern world. Azo dyes are major culprits of water pollution due to presence of complicated azo bond. Synthetic wastewater with high concentration of azo dyes has been treated using different adsorbents in this study. This exploration technique is proved to be conservative, appealing and compelling for the removal of dyes from wastewater. In this investigation, pre-treated sugarcane bagasse and chicken eggshell were utilized as an adsorbent for adsorption of azo dyes from wastewater. All the experiments were allowed to run for 160 minutes. These adsorbents satisfactorily served the purpose of application. Eggshells and sugarcane bagasse and presented 79% and 73% removal of reactive red-1 respectively. Removal of direct blue-1 was observed as 96% and 95% using eggshells and sugarcane bagasse respectively.

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Effects of nutrient loading on Anabaena flos-aquae biofilm: biofilm growth and nutrient removals

Water Science & Technology ◽

10.2166/wst.2016.208 ◽

2016 ◽

Vol 74 (2) ◽

pp. 385-392 ◽

Cited By ~ 3

Author(s):

Xiaowei Li ◽

Qun Wei ◽

Xiaojie Tu ◽

Yuxuan Zhu ◽

Yanfei Chen ◽

...

Keyword(s):

Nutrient Loading ◽

Synthetic Wastewater ◽

High Biological Activity ◽

Biofilm Growth ◽

Biofilm Thickness ◽

Nutrient Loadings ◽

High Nutrient ◽

Removal Efficiencies ◽

Algal Biofilm ◽

Structure And Functions

Effects of three different nutrient loadings (low nutrient loading, medium nutrient loading and high nutrient loading, denoted as LNS, MNS and HNS, respectively) on the structure and functions of algal biofilm using Anabaena flos-aquae were investigated using synthetic wastewater. Nutrients removal efficiencies, biofilm thickness, microalgae dehydrogenase activity (DHA) and exopolysaccharide (EPS) productions were examined. Results showed that the changes of nutrient concentration were insignificant after 4 days of experiment for the case of HNS condition; 9 days for the case of MNS condition, and 6 days for the case of LNS condition, respectively. The biofilm thickness, nutrient removal efficiencies, algae DHA and EPS productions increased with the increase of nutrient loadings in synthetic wastewater. For the case of HNS condition, the microalgal biofilm exhibited the best performance in terms of C, N and P removal efficiencies, reaching the removal rates of 68.45, 3.56 and 1.61 mg·L−1·d−1 for C, N, P, respectively. This was likely because, fact with the high nutrient loading, the high biological activity could be achieved, thus resulting in high nutrient removals. The thickness of the biofilm in HNS condition was 75 μm, which was closely related to EPS production. DHA and EPS concentrations were 7.24 and 1.8 × 10−2 mg·mm−2, respectively. It was also shown that apart from the nutrient loading, the structure and functions of microalgal biofilm were also influenced by other factors, such as illumination and temperature.

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Acrylonitrile removal from synthetic wastewater and actual industrial wastewater with high strength nitrogen using a pure bacteria culture

Water Science & Technology ◽

10.2166/wst.2001.0110 ◽

2001 ◽

Vol 43 (2) ◽

pp. 349-354 ◽

Cited By ~ 5

Author(s):

C.-C. Wang ◽

C.-M. Lee ◽

P.-W. Cheng

Keyword(s):

Industrial Wastewater ◽

High Strength ◽

Sole Source ◽

Synthetic Wastewater ◽

High Concentration ◽

Carbon And Nitrogen ◽

Abs Resin ◽

Metabolic Activities ◽

Bacteria Culture ◽

Butadiene Styrene

A gram-negative rod-shaped bacteria (strain AAS6), capable of utilizing acrylonitrile as the sole source of both carbon and nitrogen, was utilized to investigate the removal of acrylonitrile in ABS resin manufacturing wastewater. Both synthetic wastewater, containing a high concentration of acrylonitrile, and actual wastewater obtained from an ABS manufacturing factory were used. The result indicated that strain AAS6 was capable of completely removing acrylonitrile from synthetic wastewater containing less than 889 mg/l acrylonitrile and from actual industrial wastewater containing less than 400 mg/l acrylonitrile. Whether in synthetic wastewater or actual industrial wastewater, strain AAS6 showed approximately the same ability for acrylonitrile removal and used acrylic acid, a metabolic by-product of acrylonitrile, as the carbon source and ammonium as the nitrogen source. The bacteria could not directly metabolize other chemicals found in the actual industrial wastewater. However, its metabolic activities were not inhibited by the presence of compounds such as butadiene, styrene or acrylonitrile-styrene polymer. Thus, this strain is expected to play an important role in aeration tanks for treating ABS resin manufacturing wastewater.

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High-Rate Nitrification Using Aerobic Granular Sludge

Water Science & Technology ◽

10.2166/wst.2006.087 ◽

2006 ◽

Vol 53 (3) ◽

pp. 147-154 ◽

Cited By ~ 16

Author(s):

S. Tsuneda ◽

M. Ogiwara ◽

Y. Ejiri ◽

A. Hirata

Keyword(s):

Activated Sludge ◽

Removal Rate ◽

Granular Sludge ◽

Ammonia Removal ◽

High Rate ◽

Pure Oxygen ◽

Synthetic Wastewater ◽

Aerobic Granular Sludge ◽

Fluidised Bed ◽

High Concentration

The performance of nitrifying granules, which had been produced in an aerobic upflow fluidised bed (AUFB) reactor, was investigated in various types of ammonia-containing wastewaters. When pure oxygen was supplied to the AUFB reactor with a synthetic wastewater containing a high concentration of ammonia (500 g-N/m3), the ammonia removal rate reached 16.7 kg-N/m3/day with a sustained ammonia removal efficiency of more than 80%. The nitrifying granules possessing a high settling ability could be retained with a high density (approximately 10,000 g-MLSS/m3) in a continuous stirring tank reactor (CSTR) even under a short hydraulic retention time (44 min), which enabled a high-rate and stable nitrification for an inorganic wastewater containing low concentrations of ammonia (50 g-N/m3). Moreover, the nitrifying granules exhibited sufficient performance in the nitrification of real industrial wastewater containing high concentrations of ammonia (1,000–1,400 g-N/m3) and salinity (1.2–2.2%), which was discharged from metal-refinery processes. When the nitrifying granules were used in cooperation with activated sludge to treat domestic wastewater containing organic pollutants as well as ammonia, they fully contributed to nitrification even though a part of activated sludge adhered onto the granule surfaces to form biofilms. These results show the wide applicability of nitrifying granules to various cases in the nitrification step of wastewater treatment plants.

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Effects of High Salinity on Alginate Fouling during Ultrafiltration of High-Salinity Organic Synthetic Wastewater

Membranes ◽

10.3390/membranes11080590 ◽

2021 ◽

Vol 11 (8) ◽

pp. 590

Author(s):

Weiwei Cai ◽

Qiuying Chen ◽

Jingyu Zhang ◽

Yan Li ◽

Wenwen Xie ◽

...

Keyword(s):

High Salinity ◽

Synthetic Wastewater ◽

Carboxyl Groups ◽

Knowledge Gap ◽

High Concentration ◽

Saline Environments ◽

Cake Layer ◽

Salinity Wastewater ◽

Subsequent Addition ◽

Organic Wastewater

Ultrafiltration is widely employed in treating high-salinity organic wastewater for the purpose of retaining particulates, microbes and macromolecules etc. In general, high-salinity wastewater contains diverse types of saline ions at fairly high concentration, which may significantly change foulant properties and subsequent fouling propensity during ultrafiltration. This study filled a knowledge gap by investigating polysaccharide fouling formation affected by various high saline environments, where 2 mol/L Na+ and 0.5-1.0 mol/L Ca2+/Al3+ were employed and the synergistic influences of Na+-Ca2+ and Na+-Al3+ were further unveiled. The results demonstrated that the synergistic influence of Na+-Ca2+ strikingly enlarged the alginate size due to the bridging effects of Ca2+ via binding with carboxyl groups in alginate chains. As compared with pure alginate, the involvement of Na+ aggravated alginate fouling formation, while the subsequent addition of Ca2+ or Al3+ on the basis of Na+ mitigated fouling development. The coexistence of Na+-Ca2+ led to alginate fouling formed mostly in a loose and reversible pattern, accompanied by significant cracks appearing on the cake layer. In contrast, the fouling layer formed by alginate-Na+-Al3+ seemed to be much denser, leading to severer irreversible fouling formation. Notably, the membrane rejection under various high salinity conditions was seriously weakened. Consequently, the current study offered in-depth insights into the development of polysaccharide-associated fouling during ultrafiltration of high-salinity organic wastewater.

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Removal Efficiencies of Constructed Wetland Planted with Phragmites and Vetiver in Treating Synthetic Wastewater Contaminated with High Concentration of PAHs

Sustainability ◽

10.3390/su12083357 ◽

2020 ◽

Vol 12 (8) ◽

pp. 3357

Author(s):

Rabia Alsghayer ◽

Ali Salmiaton ◽

Thamer Mohammad ◽

Azni Idris ◽

Che Fauziah Ishak

Keyword(s):

Constructed Wetlands ◽

Aromatic Hydrocarbons ◽

Translocation Factor ◽

Root Systems ◽

Synthetic Wastewater ◽

High Concentration ◽

Removal Rates ◽

Polycyclic Aromatic ◽

Removal Efficiencies ◽

High Concentrations

This study aimed to evaluate the capability of horizontal subsurface flow constructed wetlands (HSFCWs) in treating contaminated wastewater with a high concentration of polycyclic aromatic hydrocarbons (PAHs) (Phenanthrene, Pyrene, and Benzo[a]Pyrene), using two plants, namely Phragmites and Vetiver. The investigated parameters were (1) PAHs uptake by the plants, (2) PAHs removal efficiencies, (3) accumulated PAHs in the soil of CWs, (4) shoot/root concentration factor, (5) translocation factor, and (6) PAHs correlation to lipid contains in the plants. During the treatment period, the results showed that the highest concentration of Phenanthrene in the shoot and the root systems of Phragmites, was 229.3 and 192 μg/g; Pyrene was 69.1 and 59.2 µg/g; and Benzo[a]Pyrene 25.1 and 20.2 µg/g, respectively. Meanwhile, in the Vetiver shoot and root systems were Phenanthrene 87.5 and 64.1 µg/g; Pyrene 63.2 and 42.1 µg/g; and Benzo[a]Pyrene 21.3 and 27.3 µg/g, respectively. The removal rates of Phenanthrene, Pyrene, and Benzo[a]Pyrene (PAHs compounds) by the CW planted with Phragmites were found to be 83%, 71%, and 81%, respectively, while the removal rates by CW planted with Vetiver were found to be 67%, 66%, and 73%, respectively. Moreover, the removal rates by unplanted CW were found to be 62%, 58%, and 55%, respectively. The results indicated that the HSFCW planted with Phragmites has an effective pathway to remove high concentrations of PAHs.

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Effect of internal recycle rate on the high-strength nitrogen wastewater treatment in the combined UBF/MBR system

Water Science & Technology ◽

10.2166/wst.2005.0372 ◽

2005 ◽

Vol 51 (10) ◽

pp. 241-247 ◽

Cited By ~ 7

Author(s):

Y.T. Ahn ◽

S.T. Kang ◽

S.R. Chae ◽

J.L. Lim ◽

S.H. Lee ◽

...

Keyword(s):

Surface Charge ◽

Removal Efficiency ◽

Nitrogen Removal ◽

Membrane Fouling ◽

Extracellular Polymeric Substances ◽

Synthetic Wastewater ◽

High Concentration ◽

Combined System ◽

Recycle Rate ◽

Influent Flow

An anaerobic/aerobic system combining an anaerobic upflow-sludge bed filter (UBF) and an aerobic membrane bioreactor (MBR) was operated to enhance organic and nitrogen removal efficiency. The internal recycle rate, which is one of the most important operation factors that affects overall removal efficiency, was varied from 100% to 300% of the influent flow. Under these conditions, the overall removal efficiencies of organic and nitrogen and characteristics of membrane fouling in the combined system treating the synthetic wastewater including high concentration of organics and nutrients were studied. As a result, nitrogen removal efficiency was increased to 67% when the internal recycle rate was 300% of influent flow rate. As the internal recycle ratio increased from 100% to 200%, protein content decreased by 17% and carbohydrate content increased by 12%. However, there was no remarkable difference in total extracellular polymeric substances (EPS) content. At the high recycle rate of 300%, the surface charge of sludge was decreased while hydrophobicity (specific ultraviolet absorbance, SUVA) was increased. The differences in SUVA and surface charge were 11% and 1%, respectively. It is concluded that SUVA and EPS composition were important parameters affecting membrane fouling in the combined system.

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