Metal ion recovery from electrodialysis-concentrated plating wastewater via pilot-scale sequential electrowinning/chemical precipitation

: A variety of processes were reported for efficient removing of heavy metal from wastewater, including but not limited to ion exchange, reverse osmosis, membrane filtration, flotation, coagulation, chemical precipitation, solvent extraction, electrochemical treatments, evaporation, oxidation, adsorption, and biosorption. Among the aforementioned techniques, adsorption/ion exchange has been known as a most important method for removing heavy metal ions and organic pollutants due to great removal performance, simple and easy process, cost-effectiveness and the considerable choice of adsorbent materials. : Nanotechnology and its applications have been developed in most branches of science and technology. Extensive studies have been conducted to remove heavy metal ions from wastewater by preparation and applications of various nanomaterials. Nanomaterials offer advantages in comparison to other materials including an extremely high specific surface area, low-temperature modification, short intraparticle diffusion distance, numerous associated sorption sites, tunable surface chemistry, and pore size. In order to evaluate an adsorbent, two key parameters are: the adsorption capacity and the desorption property. The adsorption parameters including the absorbent loading, pH and temperature, concentration of heavy metal ion, ionic strength, and competition among metal ions are often studied and optimized. : Several reviews have been published on the application of Graphene (G), Graphene Oxide (GO) in water treatment. In this minireview, we attempted to summarize the recent research advances in water treatment and remediation process by graphene-based materials and provide intensive knowledge of the removal of pollutants in batch and flow systems. Finally, future applicability perspectives are offered to encourage more interesting developments in this promising field. This minireview does not include patent literature.

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Treatment of Wastewater from Flue Gas Cleaning

Water Science & Technology ◽

10.2166/wst.1994.0498 ◽

1994 ◽

Vol 29 (9) ◽

pp. 307-312 ◽

Cited By ~ 2

Author(s):

Michael Vendrup ◽

Christina Sund

Keyword(s):

Heavy Metals ◽

Flue Gas ◽

Chemical Precipitation ◽

Pilot Scale ◽

Full Scale ◽

Basic Operation ◽

Gas Treatment ◽

Gas Cleaning ◽

Operation Rules ◽

The Usa

Wet scrubber systems for flue gas treatment, giving rise to a production of wastewater contaminated with heavy metals, are used at many coal-fired power stations in Europe, the USA and Japan. In order to remove the heavy metals from the wastewater, chemical precipitation with hydroxide and sulphide is applied. Results from two full-scale plants are given. Due to strict regulations for landfilling of waste contaminated with heavy metals, the amount of sludge must be minimised. Different techniques to meet this requirement are described. Biological post-treatment to reduce the nitrogen content of the wastewater will apparently be a need in the future, and pilot-scale testing is presently being carried out to determine the basic operation rules for a full-scale plant.

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Heavy metal removal from winery wastewater in the case of restrictive discharge regulation

Water Science & Technology ◽

10.2166/wst.2007.479 ◽

2007 ◽

Vol 56 (2) ◽

pp. 111-120 ◽

Cited By ~ 11

Author(s):

G. Andreottola ◽

M. Cadonna ◽

P. Foladori ◽

G. Gatti ◽

F. Lorenzi ◽

...

Keyword(s):

Heavy Metal ◽

Metal Removal ◽

Heavy Metal Removal ◽

Chemical Precipitation ◽

Pilot Scale ◽

Winery Wastewater ◽

Removal Of Heavy Metals ◽

Discharge Regulation ◽

Pre Treatment ◽

Cu And Zn

In most cases of winery effluent, the heavy metal content, especially zinc (Zn) and copper (Cu), does not meet the limits for the discharge as imposed by the most restrictive regulations at international level (0.4 mgCu/L and 1.0 mgZn/L in the Italian regulations). An alternative for the reduction of Cu and Zn is the on-site pre-treatment of wastewater at the winery in order to meet the limits for the discharge into the public sewerage. The purpose of this study is to evaluate the effectiveness of a pre-treatment based on chemical precipitation with chelating agents (TMT: 2,4,6-trimercaptotriazine), for the reduction of Cu and Zn from raw winery wastewater. The chemical precipitation was optimised at lab-scale through jar tests in order to evaluate the optimal dosages. An average dosage equal to 0.84 mL of TMT (15%) for 1 mg of Cu removed was estimated. Furthermore, the efficiency of the on-site chemical pre-treatment was investigated at pilot scale. The results confirmed the feasibility of using TMT treatment for the reduction of Cu and Zn in order to meet the limits for discharge into the sewerage. Contextually to the removal of heavy metals, the chemical pre-treatment allowed us to obtain the reduction of particulate COD and TSS. Finally, the costs for the operation and the management of the on-site pre-treatment were evaluated.

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The Influence of Synthesis Conditions on Hydroxyapatite Adsorption Characteristics in the Process of Zn(II) and Pb(II) Removal from Single and Binary Solutions

Revista de Chimie ◽

10.37358/rc.18.4.6196 ◽

2018 ◽

Vol 69 (4) ◽

pp. 759-766

Author(s):

Rodica Elena Patescu ◽

Claudia Maria Simonescu ◽

Gheorghe Nechifor ◽

Christu Tardei ◽

Ionela Camelia Ionascu

Keyword(s):

Heavy Metal ◽

Metal Ion ◽

Calcium Nitrate ◽

Chemical Precipitation ◽

Isotherm Models ◽

Calcium Nitrate Tetrahydrate ◽

Binary Solutions ◽

Synthesis Conditions ◽

Lead And Zinc ◽

Nitrate Tetrahydrate

Two types of nanohydroxyapatite samples have been obtained by wet chemical precipitation synthesis, involving calcium nitrate tetrahydrate and diammonium hydrogen phosphate as precursors in different conditions. Powders obtained were characterized by X-ray diffraction (XRD) and FTIR spectroscopy. The equilibrium isotherm models related with lead and zinc ions removal from synthetic aqueous solutions have been also investigated. According to this research study, it has been found that the nanohydroxyapatite samples show good heavy metals adsorption capacity, and selectivity for lead ions. It was also observed a slow decreasing of sorption capacity of heavy metal ions from binary solutions compared to that registered from single heavy metal ion solutions.

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Enhanced phosphorus removal by microbial-collaborating sponge iron

Water Science & Technology ◽

10.2166/wst.2015.323 ◽

2015 ◽

Vol 72 (8) ◽

pp. 1257-1265 ◽

Cited By ~ 3

Author(s):

Ya'e Wang ◽

Jie Li ◽

Siyuan Zhai ◽

Zhiyong Wei ◽

Juanjuan Feng

Keyword(s):

Phosphorus Removal ◽

Electrochemical Corrosion ◽

Domestic Wastewater ◽

Chemical Precipitation ◽

Pilot Scale ◽

Chemical Oxidation ◽

Sponge Iron ◽

Phosphorus Concentration ◽

Total Phosphorus Concentration ◽

Scale Experiment

The collaborative and mutually reinforcing phosphorus removal in domestic wastewater in a sponge iron and microorganisms system was studied through a laboratory and a pilot scale experiment. The results showed that the total phosphorus concentration of the effluent of less than 0.5 mg/L could be achieved. The results also support that the biochemical reaction accelerated the iron electrochemical corrosion. As a driving force, iron bacteria strengthened the chemical oxidation of Fe(II) to Fe(III). The chemical precipitation of Fe(III) is the main form of phosphorus removal. In addition, there exists adsorption phosphorus removal by phosphate-accumulating organisms. The mechanism of the enhanced phosphorus removal by microbial-collaborating sponge iron was thus proposed.

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Evaluation of substrate clogging processes in vertical flow constructed wetlands

Water Science & Technology ◽

10.2166/wst.2003.0272 ◽

2003 ◽

Vol 48 (5) ◽

pp. 25-34 ◽

Cited By ~ 104

Author(s):

G. Langergraber ◽

R. Haberl ◽

J. Laber ◽

A. Pressl

Keyword(s):

Constructed Wetlands ◽

Substrate Surface ◽

Infiltration Rate ◽

Chemical Precipitation ◽

Pilot Scale ◽

Vertical Flow ◽

Infiltration Capacity ◽

Vertical Flow Constructed Wetlands ◽

Operational Problem ◽

Water And Wastewater

Substrate clogging is by far the biggest operational problem of vertical flow constructed wetlands. The term “substrate clogging” summarises several processes which lead to reduction of the infiltration capacity at the substrate surface. The lower infiltration rate causes a reduced oxygen supply and further leads to a rapid failure of the treatment performance. Reasons for substrate clogging include accumulation of suspended solids, surplus sludge production, chemical precipitation and deposition in the pores, growth of plant-rhizomes and roots, generation of gas and compaction of the clogging layer. However, it is not clear how much each process contributes to the clogging process. Detailed investigations were carried out at pilot-scale constructed wetlands (PSCWs) using a variety of methods: e.g. soil physical investigations, microbial methods, and various analysis methods of drinking water and wastewater. The paper shows the results of these investigations and presents an equation to calculate the theoretical clogging time.

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Removal of Heavy Metals from Water: Technological Advances and Today's Lookout Through Membrane Applications

International Journal of Membrane Science and Technology ◽

10.15379/2410-1869.2021.08.01.01 ◽

2021 ◽

Vol 8 (1) ◽

pp. 1-21

Author(s):

Chendake Yogesh ◽

Mahajan-Tatpate Pallavi ◽

Dhume Supriya

Keyword(s):

Heavy Metal ◽

Reverse Osmosis ◽

Metal Ion ◽

Separation Efficiency ◽

Environmental Concern ◽

Chemical Precipitation ◽

Chemical Contamination ◽

Recovery Method ◽

Technological Advances ◽

Operational Issues

Water contamination by heavy metal is a great environmental concern. It leads to many health issues ranging from diarrhoea, vomiting to life-threatening diseases like cancer, lung/kidney damage. This also affects soil biota/plant growth. Metal-ions have a tendency of bio-accumulation, hence pose a major issue upon entry in the food-cycle. Their removal from water is necessary before use for human/agricultural applications. Different methods reported for metal-ion separation are conventional methods viz. chemical-precipitation, ion-exchange, adsorption, coagulation, flocculation, flotation, electrochemical possess good separation efficiency, but the generation of a secondary pollutant, recovery issues restrict their applicability. Hence, there is a need of reliable techno-economical, environment-friendly, sustainable separation, recovery method. Membrane-based methods viz. reverse-osmosis, nano filtration, electrodialysis, ultrafiltration has ability to treat water for heavy metal recovery without chemical contamination. Recovered materials can be recycled/utilized further. Among different membrane-based processes, micellar/polymer enhanced ultrafiltration requires chemical addition and affects purity. Electrodialysis, reverse-osmosis, nanofiltration processes require large energy/operational issues. Hence, simple ultra filtration with membrane modification is preferable as low-energy requirements. This paper discusses details of conventional/advanced methods for heavy metal separation with the fundamental process, parameters, advantages/limitations.

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Long-Term Performance of a Pilot Scale Combined Chemical Precipitation-Ultrafiltration Technique for Waste Brine Regeneration at Chevron Steam Flooding Plant

Journal of Engineering and Technological Sciences ◽

10.5614/j.eng.technol.sci.2020.52.4.4 ◽

2020 ◽

Vol 52 (4) ◽

pp. 501

Author(s):

I Gede Wenten ◽

Khoiruddin Khoiruddin ◽

Ahmad Nurul Hakim ◽

Putu T.P. Aryanti ◽

Nengsi Rova

Keyword(s):

Chemical Precipitation ◽

Pilot Scale ◽

Steam Flooding ◽

Long Term Performance ◽

Term Performance

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Nutrients removal mechanisms in high rate algal pond treating rural domestic sewage in East China

Water Science & Technology Water Supply ◽

10.2166/ws.2006.956 ◽

2006 ◽

Vol 6 (6) ◽

pp. 43-50 ◽

Cited By ~ 7

Author(s):

Q. Zhou ◽

S.L. He ◽

X.J. He ◽

X.F. Huang ◽

B. Picot ◽

...

Keyword(s):

Ammonia Volatilization ◽

Sewage Treatment ◽

Chemical Precipitation ◽

Pilot Scale ◽

Domestic Sewage ◽

High Rate ◽

East China ◽

Septic Tank ◽

Nitrogen And Phosphorus ◽

N Removal

This study focused on the evaluation of performance and mechanisms of a high-rate algal pond system (HRAP System) in nitrogen and phosphorus removal for rural domestic sewage treatment. A pilot scale HRAP System was located at Yangzhu Village, Jiangsu Province, east China, with treatment processes including a septic tank, two stages of HRAPs and an aquatic pond. Results showed that the HRAP System had a good performance in nutrient removal, especially in NH+4-N removal. Total removal efficiencies of COD, TN, NH+4-N and TP were 80, 51.8, 90.2 and 52.1%, respectively. About 61.6% of NH+4-N in the 1st-stage HRAP and 70.9% in the 2nd-stage HRAP were transformed into NO−3-N and NO2−-N through nitrification, and the nitrogen losses via ammonia volatilization was only 2.7% (for 1st-stage HRAP) and 8.8% (for 2nd-stage HRAP). The other 35.7% and 20.3% of NH+4-N removal were achieved by algae assimilation respectively. About 98.0% (for 1st-stage HRAP) and 84.8% (for 2nd-stage HRAP) removal of TN were attributed to algae sedimentation, while those through ammonia volatilization were only 2.0% (for 1st-stage HRAP) and 15.4% (for 2nd-stage HRAP), respectively. Therefore, the main mechanisms of NH+4-N removal in HRAP were nitrification and algae assimilation, and TN was mainly removed by algae sedimentation. About 50.7% (for 1st-stage HRAP) and 53.1% (for 2nd-stage HRAP) of phosphorus in the deposit were organic phosphates respectively, only 20.7% and 27.7% were calcium-bound and magnesium-bound phosphates. The removal mechanism of TP in HRAP could be mainly attributed to algae assimilation in forms of organic phosphate, and chemical precipitation in forms of calcium-bound and magnesium-bound.

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