Ten Years of THP AAD for Biosolids Management in Beijing – Strategies and Performance

Liao, Z., Zhang, R., Zhao, N., Gao, J., Yao, D., Deng, Q., Cui, C., Dai, M., Chauzy, J., Kleiven, H., Deng, D.

IWA Water and Development Congress & Exhibition (2025)

Abstract

This paper reviews strategies and performance of biosolids management in Beijing Drainage Group (BDG) with thermal hydrolysis process (THP) advanced anaerobic digestion (AAD) as core technologies to build up 5 sludge facilities to upgrade the existing facilities (Gaobeidian and Xiaohongmen) or construct totally new facilities (Huaifang, Qinghe II, and Gaoantun), treating 1200 tDS/d of dewatered sewage sludge for 13 water reclamation plants (WRPs) in Beijing downtown area. Five plants have been put in commercial operation since 2017 (Xiaohongmen (2017), Gaobeidian (2017), Huaifang (2018), Gaoantun (2018), and Qinghe II (2021)). THP AAD has been performing very well for continuously robust operation, stable digestion performance, satisfied biogas production, significant cake reduction, and Class A biosolids quality for land application. Extensive practice of THP AAD in Beijing exemplifies its suitability for water utilities in mega-cities worldwide to achieve their energy saving and carbon neutrality goals. 

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