Evaluating the impact of replacing synthetic detergents with fatty acids made soap on microbial dynamics and wastewater treatment efficiency

Chairattanamanokorn, Prapaipid; Imai, Tsuyoshi; Sudiartha, Gede Adi Wiguna; Fujii, Akihiko; Migita, Yoshiomi; Kitazato, Miho; Yoshida, Miki; Kanyama, Takahide; Kawahara, Takayoshi

doi:.0..

DOI: https://doi.org/10.4491/eer.2024.327

Evaluating the impact of replacing synthetic detergents with fatty acids made soap on microbial dynamics and wastewater treatment efficiency

Prapaipid Chairattanamanokorn¹, Tsuyoshi Imai²^†, Gede Adi Wiguna Sudiartha^2,3, Akihiko Fujii⁴, Yoshiomi Migita⁴, Miho Kitazato⁴, Miki Yoshida⁵, Takahide Kanyama⁵, and Takayoshi Kawahara⁵

¹Department of Environmental Engineering and Management, Faculty of Environment, Kasetsart University, Bangkok 10900, Thailand
²Graduate School of Sciences and Technology for Innovation, Yamaguchi University, Yamaguchi 755-8611, Japan
³Environmental Engineering Study Program, Faculty of Engineering, Udayana University, Bali 80361, Indonesia
⁴Kyushu Environmental Evaluation Association, Fukuoka 813-0004, Japan
⁵SHABONDAMA SOAP Co., Ltd., Fukuoka 808-0195, Japan

Corresponding Author: Tsuyoshi Imai ,Tel: +81-836-85-9300, Email: imai@yamaguchi-u.ac.jp

Received: June 1, 2024; Accepted: October 19, 2024.

ABSTRACT

Synthetic detergent contains linear alkyl sulfonate (LAS) that presents a greater environmental risk compared to other contaminants. There has been an interest in replacing synthetic detergent with a more biodegradable detergent made from a mixture of sodium and potassium fatty acid. The present study conducted a field experiment by replacing the usage of detergent with soap (a combination of sodium and potassium fatty acid) in two household areas to evaluate the divergent effect of detergent and soap on the microbiome of the activated sludge process for sewage treatment. Results indicated that the use of soap increased the abundance of fatty acid-consuming bacteria and nitrogen-fixation bacteria. Additionally, soap enables more bacteria strains to be proactive in degrading organic matter, LAS, anionic, and nonionic surfactants. Consequently, replacing detergents with soap in WWTP service areas can positively influence microbial dynamics, improving the overall efficiency of the wastewater treatment process.

Keywords: Fatty acid soap | Linear alkylbenzene sulfonate | Metagenomic | Synthetic detergent | Wastewater treatment