Tái định hình quản lý bùn thải trong nuôi cá rô phi thâm canh: Tích hợp công nghệ xử lý, thu hồi tài nguyên và thích ứng vùng nước lợ

Abstract

The intensification of Nile tilapia (Oreochromis niloticus) farming is creating severe pressure from solid waste, threatening the sustainability of aquaculture ecosystems in key regions such as the Mekong Delta. To address this challenge, this paper aims to synthesize and analyze current sludge treatment methods, thereby proposing integrated management strategies based on circular economy principles. Through a critical review of data from relevant studies (2006–2025), the paper clarifies mass flows, technological efficiencies, and associated risks, contributing a comprehensive framework for sludge management adapted to both freshwater and brackish ecological conditions. The results indicate three strategic pillars. First, regarding biosafety, the sludge management regime determines resource quality; current data suggest that short-term periodic sludge removal (e.g., weekly) is an important factor in limiting heavy metal accumulation (Cd, Pb, Cr, Cu). Second, a distinct technological trade-off exists: anaerobic digestion combined with co-digestion is optimal for energy recovery (biogas), whereas aerobic processes are superior for phosphorus and nitrate mineralization in hydroponic systems. Third, for saline-intruded coastal areas, UASB technology shows potential as an alternative to stabilization ponds due to its ability to overcome salinity inhibition. Finally, the paper proposes an integrated management framework that directs the transformation of waste sludge into high-value fertilizer and energy.

Keywords: Biosafety and heavy metals, Circular economy, Tilapia sludge management, Brackish water adaptation, Resource recovery