富油型好氧颗粒污泥的形成机制和产油性能研究

Regarding the deterioration of water environment and energy crisis, development of wastewater treatment technologies coupled with biodiesel production is most important in wastewater research field. Aerobic granular sludge (AGS) is a promising wastewater treatment biotechnology which has been shown great potential for replacing the widely applied activated sludge process, while this technology produces low value excess sludge. On the other hand, difficulty in microalgae harvesting and carrier instability to a great extent hinder the application of microalgae technologies in real wastewater treatment. This study aims to cultivate oil-rich AGS from municipal wastewater with efficient oil-producing algae species immobilized, simultaneously achieving high pollutants removal efficiency, high oil content and excellent biomass settleability from treated water. This work will elucidate the effects of key influencing factors (aeration strength, settling time and illumination intensity) on the formation of oil-rich AGS along with its mechanisms by using various analytical and characterization methods. Moreover, the influences of nutritional elements (like organics, N and P) and the involved mechanisms on oil production performance (oil content, oil production rate and oil quality) of the oil-rich AGS will be further explored. This research is also expected to obtain the optimal operation conditions under which stable and efficient cultivation of oil-rich AGS (with lipids content ≥ 20%) will be achieved. This study will not only contribute to the in-depth research on oil-rich AGS and its application in practice, but also provide a new concept and approach for coupling wastewater treatment with resource reclamation.

在水环境恶化和能源危机的背景下，开发稳定高效的污水净化与生物柴油相耦合技术是当前污水处理领域的重要方向。本研究拟以城市生活污水为研究对象，针对好氧颗粒污泥产生低附加值剩余污泥、微藻法采收难和菌藻固定化法载体不稳定等问题，开发出富油型好氧颗粒污泥技术，同时实现污水的高效净化与资源化。本课题将结合多种分析手段，系统研究富油型好氧颗粒污泥形成的关键影响因素及其影响机制，揭示富油型好氧颗粒污泥的形成机理；并阐明污水中营养物质（有机物、氮和磷）对颗粒产油性能（脂质含量、油脂产率和油脂质量）的影响和原理。通过本课题研究，还将获得最佳运行条件以实现稳定、高效地培养富油型好氧颗粒污泥（脂质含量≥20% dw）。本项目不仅可为富油型好氧颗粒污泥的深入研究和实际应用提供理论基础和技术指导，还可为污水高效净化与资源化相耦合技术的开发提供新思路。

高效净化与资源化技术开发是污水处理发展的重要方向，本项目借鉴好氧颗粒污泥技术，培育出了自固定化的富油型菌藻共生好氧颗粒污泥，使其具有污水处理效率高、沉降性能好、含油量高的特点，解决好氧颗粒污泥的剩余污泥附加值低、微藻采收难和菌藻固定化的载体问题。本研究首先揭示光照强度对富油型菌藻共生好氧颗粒污泥形成、溶解氧分布、生物活性、除污性能和产油性能的影响和机理；开发了连续流反应器，在1%-4%盐度下，研究了富油型菌藻共生好氧颗粒污泥的物化特性、有机物和氮磷去除能力，基于植物激素（IAA)和超氧岐化酶阐述了菌藻的共生关系；研究了50-200 mg/L氨氮条件下富油型菌藻共生好氧颗粒污泥的生化特性，实现了短程硝化作用；筛选了单一优势藻种和复合优势藻种，探究了单一优势藻种和复合优势藻种对颗粒形成、稳定性、除污性能性能和群落结构的影响。本项目为菌藻共生好氧颗粒污泥的培养、形成机理和应用提供了数据和技术支持。