Lu Yong-Ze, Wang Hou-Feng, Kotsopoulos Thomas A, Zeng Raymond J
CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei, 230026, China.
Department of Hydraulics, Soil Science and Agricultural Engineering, School of Agriculture, Aristotle University of Thessaloniki, 54124, Thessaloniki, Greece.
Appl Microbiol Biotechnol. 2016 May;100(10):4367-74. doi: 10.1007/s00253-015-7249-y. Epub 2016 Jan 4.
In this study, a novel process for phosphorus (P) recovery without excess sludge production from granular sludge in simultaneous nitrification-denitrification and P removal (SNDPR) system is presented. Aerobic microbial granules were successfully cultivated in an alternating aerobic-anaerobic sequencing batch reactor (SBR) for removing P and nitrogen (N). Dense and stable granular sludge was created, and the SBR system showed good performance in terms of P and N removal. The removal efficiency was approximately 65.22 % for N, and P was completely removed under stable operating conditions. Afterward, new operating conditions were applied in order to enhance P recovering without excess sludge production. The initial SBR system was equipped with a batch reactor and a non-woven cloth filter, and 1.37 g of CH3COONa·3H2O was added to the batch reactor after mixing it with 1 L of sludge derived from the SBR reactor to enhance P release in the liquid fraction, this comprises the new system configuration. Under the new operating conditions, 93.19 % of the P contained in wastewater was released in the liquid fraction as concentrated orthophosphate from part of granular sludge. This amount of P could be efficiently recovered in the form of struvite. Meanwhile, a deterioration of the denitrification efficiency was observed and the granules were disintegrated into smaller particles. The biomass concentration in the system increased firstly and then maintained at 4.0 ± 0.15 gVSS/L afterward. These results indicate that this P recovery operating (PRO) mode is a promising method to recover P in a SNDPR system with granular sludge. In addition, new insights into the granule transformation when confronted with high chemical oxygen demand (COD) load were provided.
本研究提出了一种在同步硝化反硝化除磷（SNDPR）系统中从颗粒污泥中回收磷（P）且不产生剩余污泥的新方法。在交替好氧-厌氧序批式反应器（SBR）中成功培养了用于去除磷和氮（N）的好氧微生物颗粒。形成了致密且稳定的颗粒污泥，SBR系统在磷和氮的去除方面表现良好。氮的去除效率约为65.22%，在稳定运行条件下磷被完全去除。随后，为了在不产生剩余污泥的情况下提高磷的回收，采用了新的运行条件。最初的SBR系统配备了一个间歇式反应器和一个无纺布过滤器，将1.37 g三水合乙酸钠（CH3COONa·3H2O）与1 L来自SBR反应器的污泥混合后加入间歇式反应器中，以增强液相中磷的释放，这构成了新的系统配置。在新的运行条件下，废水中93.19%的磷以浓缩正磷酸盐的形式从部分颗粒污泥中释放到液相中。这部分磷可以有效地以鸟粪石的形式回收。同时，观察到反硝化效率下降，颗粒分解成更小的颗粒。系统中的生物量浓度先增加，随后保持在4.0±0.15 gVSS/L。这些结果表明，这种磷回收运行（PRO）模式是在具有颗粒污泥的SNDPR系统中回收磷的一种有前景的方法。此外，还提供了关于颗粒污泥在面对高化学需氧量（COD）负荷时转化的新见解。
