A review of the existing and emerging technologies in the combination of AOPs and biological processes in industrial textile wastewater treatment

The textile industry is known as releasing huge amounts of wastewater contaminated by a large spectrum of chemicals. There are several units (e.g. printers, mercerizing machines, finishing machines, dyers) within a dye house that generate different types of effluents, some of which (mostly dyers) work in batch mode. As a result, the wastewater composition varies significantly in concentration and time. Due to this, textile wastewater treatment can be very complicated. The recent trend in the textile industry is on-site wastewater treatment and the process water recycling. This review paper presents the recent developments in Advanced Oxidation Processes (AOPs), biological processes and their combinations for industrial textile wastewater. Most studies only investigated the mixed wastewater originating from the plants, without a deeper consideration on the effluents generated by different units within the dye house. Due to an extreme variation of the textile wastewater quality, the strategy of the division of the wastewater into separated streams according to their biodegradability is highly recommended. Particular attention has been paid in this review to the comparison of cost effectiveness of wastewater treatment processes. The presented considerations are based not only on a literature survey of the last 20 years but also on exemplified industrial cases of the application of AOPs and biological process in textile factories in Poland.