Destruction of oxalate from alumina-refining process liquor is considered essential for many alumina refineries around the world. Some refineries have embraced the use of aerobic bioreactors as a cost-effective destruction method. These processes are often supplemented with an external nitrogen (N) source to facilitate microbial activity, even though such augmentations are undesirable due to increase of operational costs. Until now, there has also only been little information on oxalate degradation kinetics, although this knowledge is essential to design bioreactor processes. Hence, this study aimed at determining oxalate degradation kinetics in two aerobic packed bed biofilm reactors under both Nsupplemented and N-deficient conditions. Michaelis-Menten equation was used to derive kinetic parameters for specific oxalate degradation. The N-deficient culture had a higher affinity (K_m of 458.4 vs. 541.9 mg/L) towards oxalate and a higher maximum specific oxalate removal rate (V_max of 161.3 vs. 133.3 mg/(h·g biomass)) compared to the N-supplemented culture, suggesting that the N-deficient culture is better suited to remove oxalate. Microbial community analysis also showed differences in the composition of the two cultures. Based on the kinetic parameters derived, a novel two step oxalate removal process was proposed that capitalises on higher specific oxalate removal rates for efficient oxalate destruction from waste streams of alumina industry.

从氧化铝精制工艺液中破坏草酸盐被认为对于全球许多氧化铝精炼厂都是必不可少的。一些炼油厂已经接受使用好氧生物反应器作为一种经济有效的销毁方法。这些过程通常补充外部氮（N）源，以促进微生物活动，尽管由于操作成本的增加，这种增加是不希望的。到目前为止，尽管草酸降解动力学的信息对于设计生物反应器工艺至关重要，但目前只有很少的信息。因此，本研究旨在确定两个氮下两个好氧填充床生物膜反应器中草酸盐的降解动力学。补充和N缺乏条件。Michaelis-Menten方程用于推导特定草酸盐降解的动力学参数。与草酸相比，缺氮培养物对草酸盐的亲和力更高（K _m为458.4对541.9 mg / L），草酸最大比去除率更高（V _max为161.3对133.3 mg /（h·g生物量））。 N补充文化，这表明N缺乏文化更适合去除草酸盐。微生物群落分析还显示了两种文化的组成差异。基于得出的动力学参数，提出了一种新颖的两步草酸盐去除工艺，该工艺利用较高的比草酸盐去除速率来从氧化铝行业的废物流中有效地去除草酸盐。