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In recent years the textile industry is characterized as qualitative fabric industry. Rawmaterials and process auxiliaries (as dyes and other chemicals) are used of very good quality.Dyes are developed to be very stable and resistant to physical and biological breakdown.Therefore they are hard degradable in natural conditions. Removal of dye residual from thewastewater requires also qualitative treatment solutions.As conventional wastewater treatment methods are unable to decompose hard degradablepollutants to the final breakdown products at the textile industry wastewater treatment unit,therefore there is a demand for more advanced treatment. Considerable attention is paid to theadvanced oxidation methods.In this paper the research results of textile reactive dyeing a11ificial wastewater treatment withadvanced oxidation method under ultraviolet light (UV) in presence of hydrogen peroxide(H202) are described. Investigated relationships are such as pH, reaction length andwastewater composition influence to the UV/He202 advanced oxidation process efficiency.From obtained results it can be concluded that UY/H202 advanced oxidation process isinhibited by high pH level, dyeing assisting chemicals, salts and anticreasing agent. Thereaction rate constant with removed disturbances is obtained up to 0.4436 min ·1, textilereactive dyeing artificial wastewater complete decolourisation is achieved within 4 to 15minutes.

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Granular activated carbon (GAC) is used in water treatment systems, typically to remove pollutants such as natural organic matter, volatile organic compounds, chlorine, taste, and odor. GAC is also used as a key component of a new technology that combines a fluidized bed reactor with radio frequency electric fields for disinfection. So far, the effects of GAC on bacteria in these fluidized bed reactors are unclear. This paper describes a systematic study of the physico-chemical changes in five microbial media compositions caused by different concentrations (23-350 g/L) of GAC, and the effects of these physico-chemical changes on the metabolic activity and survival of a model microorganism (Escherichia coli YMc10) in a fluidized bed reactor. The chemical adsorption taking place in suspensions with specific GAC changed nutritional, osmotic, and pH conditions in the investigated microbial media (LB, diluted LB, PBS, diluted PBS, and tap water), leading to a decay of the metabolic activity and survival of E. coli. Especially media that are poor in organic and mineral compounds (e.g., PBS) with suspended GAC showed a concentration decay of 3.5 Log CFU/mL E. coli after 6 h. Organic compounds depletion and severe pH variation were enhanced in the presence of higher GAC concentrations.

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