Bleaching effluents

Toxic by-products NaOCl stage H3O3 stage Rinse 1 Rinse 2 

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Caro s acid is finding increasing appHcation ia hydrometaHurgy, pulp bleaching, effluent treatment, and electronics. There are several appHcations of Caro s acid ia hydrometaHurgy. It is usually made on-site by either the isothermal or the adiabatic process. The latter method is preferred because its capital cost is less and the system is safer due to the fact that the product is used as soon as it is made. 

Efficiencies for removal in the wastewater treatment plant were estimated for total and soluble BOD, total COD, soluble COD, color, total suspended and dissolved solids, and total solids. The removal efficiencies summarized in Table 21.14 are high for total BOD, soluble BOD, and suspended solids, at 96%, 96%, and 95%, respectively. The removal efficiencies for total and soluble COD were significantly lower at 76% and 66%, respectively. The removal efficiency for color was only about 38%. This value is typical for biological treatment of pulp and paper wastewater, and may be due, at least partially, to the formation of new colored groups when the bleach effluents are oxidized in the treatment system. 

Ensio-Fenox A process for removing chlorinated phenols from pulp-bleaching effluents. It combines anaerobic and aerobic fermentation processes. 

Immobilized catalases, for textile bleaching effluent treatment, 4 68—69 Immobilized cells, 3 670 Immobilized enzyme biosensors,... 

Malmqvist A, Welander T. 1992. Anaerobic removal of chlorate form bleach effluents. Water Sci Technol 25 237-42. 

Tzanov, T. Costa, S. Guebitz, G. Cavaco-Paulo, A. Effect of temperature and bath composition on the dyeing of cotton with catalase treated bleaching effluent. J. Soc. Dyers Colour. 2001, 117, 116-170. 

Elforts have been made to characterize the nature and content of individual components that are present in the low-molecular-mass fraction of the total mill effluents, which include the spent chlorination and alkali extraction stage liquors [2,4]. Approximately 456 types of compounds have been detected in the conventional bleach effluents, of which 330 are chlorinated organic compounds [22]. The compounds may be lumped into three main groups, namely, acidic, phenolic, and neutral (Table 2). Acidic compounds are further divided into the five categories of acids fatty, resin, hydroxy, dibasic, and aromatic acids. The most important fatty acids are formic and acetic acids. The dominant resin acids are abietic and dehydroabietic acids. Among the hydroxy acids identified, glyceric acid predominates. Dibasic acids such as oxalic, malonic, succinic, and mafic acids are derived from the lignin and carbohydrate fraction... 

Kraft mill using 100% CIO2 Fish populations Changes in the reproductive development - reduction in gonad size, depression of sex hormones following exposure to bleach effluents subjected to secondary treatment Munkittricketal., 1997 [30]... 

Several physico-chemical methods are available for the treatment of pulping and pulp bleaching effluents. The most prominent methods are membrane separation, chemical coagulation, and precipitation using metal salts and advanced oxidation processes. 

Yeber, M.C. Rodriguez, J. Baeza, J. Freer, J. Zaror, C. Duran, N. Mansilla, H.D. Toxicity abatment and biodegradability enhancement of pulp mill bleaching effluent by advanced chemical oxidation. Water Sci. Technol. 1999, 40 (11-12), 337-342. 

Lepisto, R. Rintala, J.A. The removal of chlorinated phenolic compounds from chlorine bleaching effluents using thermophilic anaerobic processes. Water Set Technol. 1994, 29 (5-6), 373-380. 

Haggblom, M. Salkinoja-Salonen, M. Biodegradability of chlorinated organic compounds in pulp bleaching effluents. Water Set Technol. 1991, 24 (3/4), 161-170. 

Rintala, J.A. Lepisto, R. Thermophilic anaerobic-aerobic and aerobic treatment of Kraft bleaching effluents. Water Sci. Technol. 1993, 28 (2), 11-16. 

Eaton, D. Chang, H.-M. Kirk, T.K. Fungal decolorization of Kraft bleach effluents. Tappi J. 1980,... 

Rohm and Haas Co. Decolorization of Kraft Pulp Bleaching Effluents Using Amberlite XAD-8 Polymeric Adsorbent, IE-75 Philadelphia, 1972. 

Heinzle E, Geiger F, Fahmy M, Kut O M (1992) Integrated Ozone-Biotrealment of Pulp Bleaching Effluents Containing Chlorinated Phenolic Compounds, Biotechnology Progress 8 67-77. 

Caro s acid is finding increasing application in hydroiuelalUirgy, pulp bleaching, effluent treatment, and electronics. 

Swackhamer D, Engstrom D (2000) Toxaphene concentrations in dated sediment cores from a holding pond for kraft bleach effluent. Unpublished data. School of Public Health, University of Minnesota, MN... 

Ahtiainen, J., Nakari, T. and Silvonen, J. (1996) Toxicity of TCF and ECF pulp bleaching effluents assessed by biological toxicity tests, in M.R. Servos, K.R. Munkittrick, J.Ef. Carey and G.J. Van Der Kraak (eds.), Environmental Fate and Effects of Pulp and Paper Mill Effluents, St-Lucie Press, FL, pp. 33-40. 

Sagfors and Starck [14] used gel permeation chromatography to study calcium lignosulphate of high molecular weight in acid and alkaline kraft pulp bleaching effluents. 

Lignin, a major structural component of wood, was also degraded by a photo-Fenton technique [80]. Although this report demonstrated the ability of the method to degrade lignin, the study did not elaborate on potential applications in the pulp-and-paper industry. The treatment of kraft mill bleaching effluent by Fenton and photo-Fenton methods has been studied, and was reportedly more effective and more economical than several other techniques [81]. 

Oxidation of phenols, dyes, and polycyclic aromatic hydrocarbons [48,49], decolorization of Kraft bleaching effluents, binding of phenols and aromatic amines with humus [47] Transformation of phenols, aromatic amines, polyaromatic hydrocarbons, and other aromatic compounds, decolorization of Kraft bleaching effluents, treatment of dioxins, pyrene [86-89,114] Improved sludge dewatering [59]... 

Transformation of phenols and aromatic amines [7-24], decolorization of Kraft bleaching effluents [21], dewatering of phosphate slimes [60]... 

Pellinen J, Yin C-F, Joyce TW, Chang H-M. Treatment of chlorine bleaching effluent using a white-rot fungus. J Biotechnol 1988 8 67-76. 

Milstein O, Haars A, Majcherczyk A, Trojanowski J, Tautz D, Zanker H, Huttermann A. Removal of chlorophenols and chlorolignins from bleaching effluent by combined chemical and biological treatment. Water Sci Technol... 

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