Continuous removal of heavy metals from FGD wastewater in a fluidised bed without sludge generation

A patent pending fluid-bed process has been developed by Krüger for removal of dissolved heavy metals by adsorption/coprecipitation. The waste product is a very compact granulate with a very low water content of 10-20%. Sludge is not produced. The fluid-bed technique was tested at a coal-fired power station with wastewater from the flue gas desulphurisation (FGD) unit for removal of heavy metals from the wastewater. By dosing only potassium permanganate to the wastewater, the content of dissolved nickel, cadmium and zinc was reduced by respectively 99%, 92% and 97% at optimum treatment in one fluid-bed reactor. The weight of waste product produced will constitute less than 25% of the waste product produced by the present traditional chemical precipitation. Chemical costs are approximately 0.6 US$/m3 which are similar for the fluid-bed and present wastewater treatment processes.

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Evaluation of Different Treatment Processes for Landfill Leachate Using Low-Cost Agro-Industrial Materials

Processes ◽

10.3390/pr8010111 ◽

2020 ◽

Vol 8 (1) ◽

pp. 111 ◽

Cited By ~ 4

Author(s):

Tawfiq J. H. Banch ◽

Marlia M. Hanafiah ◽

Abbas F. M. Alkarkhi ◽

Salem S. A. Amr ◽

Nurul U. M. Nizam

Keyword(s):

Heavy Metals ◽

Physicochemical Parameters ◽

Low Cost ◽

Hazardous Substances ◽

Leachate Treatment ◽

Treatment Processes ◽

Removal Of Heavy Metals ◽

Industrial Materials ◽

Palm Oil Mill ◽

Complex Liquid

Leachate is a complex liquid that is often produced from landfills, and it contains hazardous substances that may endanger the surrounding environment if ineffectively treated. In this work, four leachate treatment applications were examined: combined leachate/palm oil mill effluent (POME) (LP), leachate/tannin (LT), pre-(leachate/tannin) followed by post-(leachate/POME) (LT/LP), and pre-(leachate/POME) followed by post-(leachate/tannin) (LP/LT). The aim of this work is to evaluate and compare the performance of these treatment applications in terms of optimizing the physicochemical parameters and removing heavy metals from the leachate. The highest efficiency for the optimization of the most targeted physicochemical parameters and the removal of heavy metals was with the LP/LT process. The results are indicative of three clusters. The first cluster involves raw leachate (cluster 1), the second contains LP and LP/LT (cluster 2), and the third also consists of two treatment applications, namely, LT and LT/LP (cluster 3). The results demonstrate that LP/LT is the most appropriate method for leachate treatment using low-cost agro-industrial materials.

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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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