This article presents a wastewater treatment initiative in rural northwest China, addressing 2.0–20.0t/d of domestic sewage in areas with -28°C winters and 2.0m permafrost. The project deploys BioFilter-2000/5000/7000/10000 systems, featuring 14mm HDPE tanks with 2.8m soil cover for freeze resistance. These power-free, maintenance-free units treat wastewater efficiently, with summer effluent reused for agricultural irrigation and winter discharge meeting local standards. The solution overcomes geographical isolation and extreme cold, setting a precedent for sustainable rural wastewater management in harsh climates.

This article presents a wastewater treatment project for a Vietnamese enterprise's living area with a daily treatment capacity of 30.0 tons. Located in a remote area lacking professional maintenance personnel, the project employs multiple parallel BioFilter-10000 units—an innovative, power-free, and maintenance-free purification system. The BioFilter-10000 addresses challenges of large wastewater volume and geographical isolation by enabling near-source installation, eliminating electrical requirements, and reducing reliance on technical staff. Treated effluent is recycled for on-site greenery irrigation, achieving both stable compliance with discharge standards and sustainable water resource utilization. This case highlights the system’s adaptability in remote industrial settings, showcasing its efficiency in wastewater management and contribution to circular economy practices.

Decentralized Wastewater Treatment Solution for German Villages: BioFilter's Off-Grid InnovationProject BackgroundIn rural Germany, where many villages lie beyond the reach of municipal sewer networks, a sustainable wastewater treatment solution has emerged to address the needs of communities with d