REMEDIATION AND REUSE OF RETTING FLAX WASTEWATER USING ASP FOLLOWED BY ADSORPTION ON AC
Remediation and reuse of retting flax wastewater using activated sludge process (ASP) followed by adsorption on activated carbon (AC) were investigated. Wastewater produced (350 m3/d) is characterized by brownish to yellow color, bad odor and high organic contents due to lignin, cellulose and hemicelluloses in the flax fibers wastewater. Biodegradation of the organic contaminants was achieved successfully using ASP in presence of adapted culture containing pectin enzymes released by bacteria at a detention time of 6 h. The efficiency of ASP for chemical oxygen demand (COD), biological oxygen demand (BOD) and total suspended solids (TSS) were 95.86%, 94.53% and 97.6%, respectively. For wastewater reuse, post treatment was carried out using adsorption on AC with a dose of 2 g/L and at a contact time of 45 min. kinetics and adsorption isotherm was investigated. It was found that the sorption of residual COD from flax wastewater follows the second order kinetics and data fits both Langmuir and Freundlich isotherm models. The maximum adsorption capacity (qmax) of COD over AC was 333.33 mg/g. Residual COD, BOD and TSS were 38 mg O2/L, 9 mg O2/L and 2 mg/L, respectively which comply with the National Regulatory Standards for reuse.
FAWZY ME*, BADR NM AND ABOU-ELELA SI