Dyestuffs wastewater treatment

In 1980, approximately 111,000 t of synthetic organic dyestuffs were produced in the United States alone. In addition, another 13,000 t were imported. The largest consumer of these dyes is the textile industry accounting for two-thirds of the market (246). Recent estimates indicate 12% of the synthetic textile dyes used yearly are lost to waste streams during dyestuff manufacturing and textile processing operations. Approximately 20% of these losses enter the environment through effluents from wastewater treatment plants (3). 

Schonberger H, Baumann A, Keller W, Pogopetris P (1997) Study of microbial degradation of polyvinyl alcohol (PVA) in wastewater treatment plants. American Dyestuff Reporter August 1997 9-18. Available at http //www.p2pays.org/ref/02/01722.pdf. Last accessed 16 Aug 2011... 

Recent estimates indicate 29t of the synthetic textile dyes used yearly are lost to waste streams during dyestuff manufacturing and textile processing operations. Approximately 20% of these losses enter the environment through effluents from wastewater treatment plants. 

Under the direction of M. Jose Cocero, the University of Valladolid operates a film-cooled SCWO reactor filled with AI2O3 balls for mixing and increasing conversion rates[38]. This reactor was used for the treatment of synthetic dyestuff wastewater. The reactor volume is 15 1 (effective volume 9 1) with operating conditions of 25 MPa, 600-700°C, 12-17 kg/h mass flow, organic content of 7-11 wt.%, and air oxidant. The reactor is energetically self-sufficient with feed preheated by the energy recovered from the reactor. 

Yang K, Wu W, Jing Q, Zhu L (2008) Aqueous adsorption of aniline, phenol, and their substitutes by multi-walled carbon nanotubes. Environ Sci Tech 42 7931-7936. doi 10.1021/es801463v Ye S, Huang F (2007) Separation of carcinogenic aromatic amines in the dyestuff plant wastewater treatment. Desalination 206 78-85. doi 10.1016/j.desal.2006.03.562 Yemashova N, Kalyuzhnyi S (2006) Microbial conversion of selected azo dyes and their breakdown products. Water Sci Technol 53(11) 163-171. http //www.ukpmc.ac.uk/abstract/MED/ 16862786... 

Ozonation has so far found application mostly in the treatment of surface-water, but there is also some experience in using it for wastewaters including those coming from textile mills. Thus, for example, it has been reported [1,2] that ozonation can decolour textile wastewaters, particularly those containing reactive and acid dyestuffs, whereas with the waters that contain direct, disperse or sulphur dyestuffs, the effect of ozone is markedly less persuasive. 

Pollution of wastewaters by phenols of artificial origin is caused particularly by those from the thermal processing of coal, oil refineries, from sulphite woodworking, dyestuff industry, and from the mamufacture of pesticides. These wastewaters contain monovalent and multivalent phenols at concentrations of units of g 1 . In the process of biological treatment of phenolic wastewaters different polyphenols are formed which have a similar cha-... 

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