Reuse of textile wastewater treated by moving bed biofilm reactor coupled with membrane bioreactor
Xuefei Yang, Víctor López Grimau, Mercedes Vilaseca, Martín Crespi, Judit Ribera‐Pi, Montse Calderer, Xavier Martínez‐Lladó
Abstract
Abstract A laboratory‐scale pilot plant of moving bed biofilm reactor coupled with membrane bioreactor (MBBR‐MBR) was studied with regard to wastewater treatment in the textile industry, and the reuse feasibility of treated water was investigated. The pilot plant comprised two connected parts: an aerobic tank filled with carriers and a submerged membrane tank. The MBBR‐MBR system reduced the hydraulic retention time to 1 day, which is very promising compared with conventional biological treatment in the textile industry. The removal efficiency of chemical oxygen demand reached 93%, which is almost the maximum for a biological process treating this type of wastewater, as well as the colour removal performance, which achieved 85%. Additionally, 99% of total suspended solids were removed due to filtration. Furthermore, new dyeing processes reusing the treated water were performed. The quality of the new dyed fabrics with treated water was compared with reference fabrics. Colour differences between new dyed fabrics and reference fabrics were found to be within the general requirement of the textile industry (Δ E CMC(2:1) < 1). The reuse of treated water in new dyeing processes is beneficial both for the industry and for the environment, because the textile sector is an intensive water consumer during both the dyeing and finishing processes.