Metal recovery from industrial wastes

C. S. Brooks, Metal Recovery from Industrial Wastes, Lewis Publishers, Chelsea, MI, 1991. 

Metal recovery from industrial waste has recently been shown [101] to be an active area of magnetic field applications, the base system ranging from mine-waste to cable scrap. Fe, Co, Nl, Cr, Mn, Mo, Tl, Va, W, Ta, U, rare-earth metals and precious metals are the most obvious candidates for recovery in magnetic fields, although other substances, e.g. Zn, Pb, Mg, Ca, have also been the subject of successful recovery studies [e.g. 71]. 

Brooks CS, Metal Recovery From Industrial Waste, Lewis... 

D. Mishra, Y. Rhee, Current research trends of Microbiological leaching for metal recovery from industrial wastes, in A. Mendez-Vilas (Ed.), Current Research Technology and Education Topics in Applied Microbiology and Microbial Biotechnology, Vol. 2, 2010, p. 1289. 

Complexes of alkali metals and alkaline-earth metals with carbohydrates have been reviewed in this Series,134 and the interaction of alkaline-earth metals with maltose has been described.135 Standard procedures for the preparation of adducts of D-glucose and maltose with the hydroxides of barium, calcium, and strontium have been established. The medium most suitable for the preparation of the adduct was found to be 80% methanol. It is of interest that the composition of the adducts, from D-glucose, maltose, sucrose, and a,a-trehalose was the same, namely, 1 1, in all cases. The value of such complex-forming reactions in the recovery of metals from industrial wastes has been recognized. Metal hydroxide-sugar complexes may also play an important biological role in the transport of metal hydroxides across cell membranes. 

In contrast to the situation of a decade ago [3.1). a substantial literature has now accumulated on copper removal by activated carbons. This is not only because of metal recovery from acid mine wastes [176] and acidic corrosion of pipes [33] but also because of increasing industrial contamination of water streams [177-182]. In particular.many wastewaters contain complexing ions such as ethylenedi-aminetetraacetate (EDTA) and the removal of EDTA-chelated copper (and other) ions has been a special focus of attention [45,173,183-186]. 

NATANSOHN ITT AL. Recovery of Valuable Metals from Industrial Wastes 133... 

H.M. Kelly, D. Randall and R.M. Wallace, Metal recovery from aqueous industrial wastes, Dupont Innovation, 1973, 4, 4-7. 

NDSX techniques have been deployed in separation science applications such as metal recovery from leach solutions, recovery of precious and strategic metals, and treatment of large volumes of effluents including toxic and hazardous waste generated by chemical industries [33-36]. Recovery of Sb, Cu, and Zn from industrial waste has been reported using NDSX method [37,38]. 

Production of high-purity water, concentration of food and heavy metal recovery from well water, river water, lake water, or industrial waste water Lower pressure brackish water membrane Ideal for small drinking water systems due to low energy consumption... 

D. Kratochvil, Plant Commissioning in China for Ni-Co Recovery from Low Grade Waste Solution in Recycling Metals from Industrial Waste, Colorado School of Mines, Golden, June 2011. 

Extensive studies on hollow fiber membrane based separation technology (HFMST) carried out for efficient removal of toxic heavy metals like Cr(VI), Cd, Zn, Ni, separation and concentration of gold from alkaline hydrometallurgical solution [13-26] were described in [2]. Further, recovery of valuable solutes from aqueous phases—for example, citric acid, carboxylic acid, amino acids, and L-phenylalanine [27,28]—such as removal of phenol from industrial waste water [29] are well demonstrated by using this technology and are described in detail in a later section of this chapter. 

In addition to these exemptions, there are three types of units that are conditionally exempt from the regulations. These are metal recovery furnaces, precious metal recovery units, and certain other special industrial units. In order to claim these exemptions, owners/operators must provide a onetime written notice claiming the exemption, conduct sampling, and analysis, and maintain records to demonstrate compliance with all applicable requirements. Any waste management prior to burning in this type of unit, and any resulting residues, are subject to applicable hazardous waste regulation. 

Special Industries Certain industrial units, such as secondary lead and nickel-chromium smelters and mercury recovery furnaces, and other units that process wastes from metals recovery normally do not meet the conditions required for being considered as legitimately burned for metals recovery. U.S. EPA revised the BIF standards to conditionally exclude those wastes that are processed for metals recovery, but do not meet the criteria. Waste streams in these units must contain recoverable levels of metals and the waste must not contain more than 500 mg/L of the toxic organics listed in Part 261 to be considered for this conditional exemption. 

In most countries, solid waste containing metals such as neutralization sludge from the plating industry and flue dust from the metal and steel industries is currently collected and dumped in landfill, where it constitutes a perpetual toxic threat to the environment and a waste of resources. The alternatives to this landfill disposal are either to reduce the rate of discharge at source by an individually designed recovery process or to separate and recover the metals from the collected waste in a centrally located facility. A presumption for a centrally located facility would be that companies with metals in their effluents require treatment of their total wastewater streams. This could be accomplished through the relatively simple process of neutralization, which requires minor investment in sedimentation tanks and dewatering equipment and involves relatively modest operation costs. 

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