Printing and dyeing wastewater is an complex high salt organic wastewater produced in the printing and dyeing industry, rich in a large amount of organic dyes, high concentrations of phosphorus, and other harmful components. It is widely regarded as one of the biggest challenges in industrial wastewater treatment, posing a serious threat to the natural environment, agricultural production, and even human health that cannot be ignored.
Recently, the research team led by Prof. WANG Guangce from the Institute of Oceanology of the Chinese Academy of Sciences (IOCAS) has made new progress in the use of algae to treat high salt organic wastewater.
The study was published in Chemical Engineering Journal on Nov. 6.
Biological treatment of wastewater has unique advantages that other methods do not have, as it does not produce secondary pollution and is environmentally friendly. Researchers successfully constructed an efficient bacterial/algal synergistic biological treatment system (BACTS) using Vibrio fluvialis and Chlorella sorokiniana isolated from printing and dyeing wastewater, and optimized the conditions for BACTS treatment of printing and dyeing wastewater. Under optimal conditions - that is, V. fluvialis first added, C. sorokiniana followed, V. fluvialis / C. sorokiniana inoculation ratio of 1:2, pH 6.5 and light intensity 8,000 Lux. This system exhibits excellent treatment efficiency for actual printing and dyeing wastewater, with removal rates of total phosphorus (TP), chemical oxygen demand (COD), and dyes reaching 87.31%, 73.23%, and 35.0%, respectively.
The overall water quality improvement rate reaches 55.6%, their results showed.
The synergistic system of bacteria and algae also has additional economic value. The treatment process can produce high value-added by-products including 27.63% of oil, polysaccharides of 81.1mg/g, and proteins of 16.62mg/g.
"In depth exploration of its mechanisms revealed that V. fluvialis and C. sorokiniana mainly functions through biological adsorption and biological transformation, which exhibit significant synergistic effects in BACTS, jointly accelerating the process of biodegradation and transformation," said WANG Lijun, one of first authors of the study. "Laccases, peroxidases, azoreductases and other enzymes play a crucial role in dye degradation and biotransformation processes."
"This study provides a new type of wastewater biological collaborative treatment system by utilizing local bacteria and algae, providing an efficient and economical new strategy for treating wastewater," said Prof. WANG Guangce, the corresponding author.
Construction of a Collaborative Wastewater Treatment Biological System Using Vibrio fluvialis and C. sorokiniana (Image by SONG Yuling & WANG Lijun)
Song, Y.#; Wang, L.#; Qiang, X.; Guo, M.; Gu, W.; Wu, S.; Gao, S.; Liu, X.; Xie, X.; Fan, Q.; Zhang, J.; Ma, Z.*; Wang, G*. (2024). Design, construction and evaluation of collaborative bio-system of Vibrio fluvialis with Chlorella sorokiniana for treating actual printing and dyeing wastewater. Chemical Engineering Journal , 500, 157459.
(Editor: ZHANG Yiyi)