An enhanced disintegration using refinery spent caustic for anaerobic digestion of refinery waste activated sludge. (15th April 2021)

• Record Type: Journal Article
• Authors: Li, Jin; Wang, Qinghong; Liang, Jiahao; Li, Huimin; Guo, Shaohui; Gamal El-Din, Mohamed; Chen, Chunmao
• Is Part Of: Journal of environmental management. Volume 284(2021)
• Publication Date: 2021-04-15
• Subjects: Waste activated sludge -- Disintegration -- Alkaline -- Refinery spent caustic; Environmental policy -- Periodicals; Environmental management -- Periodicals; Environment -- Periodicals; Ecology -- Periodicals; 363.705
• DOI: 10.1016/j.jenvman.2021.112022
• Languages: English
• ISSNs: 0301-4797

Abstract

Abstract: Alkali-mediated disintegration is efficient to improve the anaerobic digestion of waste activated sludge (WAS). In the present study, the role and potential of refinery spent caustic (RSC), an alkaline hazardous waste, in enhancing the disintegration of refinery waste activated sludge (RWAS) was investigated. The high alkalinity and free ammonia of RSC destroyed the microbial cell wall and promoted the release of intracellular substances. The contents of N-acetylglucosamine and proteins in the disintegrated liquid greatly increased to 0.41 mg/L and 1147 mg/L, respectively, relative to no disintegration (0.04 mg/L and 3.3 mg/L). The methane production (66.1 mL/g-VS) from RWAS anaerobic digestion increased by 226% compared to without disintegration (20.3 mL/g-VS). This study provides a newly developed "wastes-treat-wastes" management approach of refinery wastewater using combined treatment processes for RWAS and RSC using a cost-efficient and environmentally friendly disintegration of RWAS. Graphical abstract: Image 1 Highlights : Refinery spent caustic (RSC) is used to enhance the disintegration of refinery activated sludge. RSC benefits the damage of microbial cell wall and the release of cell organics. Alkali and free ammonia in RSC are the essential components for disintegration. A waste-treat-waste way for refinery sludge and RSC management is proposed.