混合态厨余发酵液作为外碳源强化脱氮的特性

Characteristics of Enhanced Nitrogen Removal with Mixed Fermentation Liquid of Food Waste as External Carbon Sources

利用混合态厨余发酵液(MFLFW)作为多段进水SBR的外碳源,考察其脱氮性能及发酵液利用规律。在93 d的运行过程中,反应器能够达到较佳的脱氮效果;MFLFW主要通过污泥生长、反硝化脱氮以及氧化过程去除,随氮负荷增高表现出较好的反硝化潜力,脱氮利用率最多为进水TCOD的29.37%。沿程分析表明,反应器在好氧段和厌氧段分别具有较高的硝化和反硝化速率,分别为(27.84±2.31)、(10.13±1.3)mg/(g MLVSS·h);且在好氧段存在同步硝化反硝化(SND)过程,周期内脱氮贡献率随每阶段进水量递减,分别为45.85%、25.31%和7.48%,进一步证实MFLFW碳源在SBR反应器中易于被利用且与SND过程关系密切。考虑到对碳源物质的消耗及利用对餐厨垃圾和污水处理均有益处,因此MFLFW碳源具有较好的应用价值。

Mixed fermentation liquid of food wastes （MFLFW） were utilized as external carbon source for enhancing nitrogen removal in the step-feeding SBR, and the characteristics of enhanced nitro- gen removal and the utilization rule of the fermentation liquid were investigated. The results showed that the reactor could achieve high nitrogen removal efficiency during the 93 d of operation. MFLFW was mainly removed through the sludge growth, denitrification and oxidation process, which showed better denitrification potential with the increase of nitrate loading and got the utilization efficiency of nitrogen re- moval up to 29.37% of the influent TCOD. The process experiment showed that the reactor had higher rate of nitrification and denitrification in aerobic and anaerobic sections, which were （ 27.84 ± 2.31 ） mg/（ gMLVSS· h） and （ 10.13 ± 1.3 ） mg/（ gMLVSS· h）, respectively. Simultaneous nitrification and denitrifieation （SND） took place in the aerobic section, and the contribution rates to nitrogen removal in each stage were 45.85%, 25.31% , and 7.48% , respectively, with the decrease of feeding volume, which confirmed that the MFLFW carbon source in SBR reactor was easy to be utilized and had close rela- tionship with SND process. Considering the benefits of the carbon source consumption and utilization for food waste treatment and sewage treatment, MFLFW carbon source has a good practical value.