Rio de Janeiro State University, Brazil.
Water Sci Technol. 2012;66(10):2131-7. doi: 10.2166/wst.2012.434.
There is a worldwide demand for decentralized wastewater treatment options. An on-site engineered ecosystem (EE) treatment plant was designed with a multistage approach for small wastewater generators in tropical areas. The array of treatment units included a septic tank, a submersed aerated filter, and a secondary decanter followed by three vegetated tanks containing aquatic macrophytes intercalated with one tank of algae. During 11 months of operation with a flow rate of 52 L h(-1), the system removed on average 93.2% and 92.9% of the chemical oxygen demand (COD) and volatile suspended solids (VSS) reaching final concentrations of 36.3 ± 12.7 and 13.7 ± 4.2 mg L(-1), respectively. Regarding ammonia-N (NH(4)-N) and total phosphorus (TP), the system removed on average 69.8% and 54.5% with final concentrations of 18.8 ± 9.3 and 14.0 ± 2.5 mg L(-1), respectively. The tanks with algae and macrophytes together contributed to the overall nutrient removal with 33.6% for NH(4)-N and 26.4% for TP. The final concentrations for all parameters except TP met the discharge threshold limits established by Brazilian and EU legislation. The EE was considered appropriate for the purpose for which it was created.
全球对分散式废水处理方案有需求。为热带地区的小型废水产生者设计了一个现场工程生态系统（EE）处理厂，采用多阶段方法。处理单元的组合包括化粪池、浸没式曝气过滤器和二级澄清池，随后是三个含有水生植物的植被化池塘，其中一个池塘中穿插着藻类。在以 52 L h(-1) 的流速运行 11 个月后，该系统平均去除了化学需氧量（COD）和挥发性悬浮固体（VSS）的 93.2%和 92.9%，最终浓度分别为 36.3 ± 12.7 和 13.7 ± 4.2 mg L(-1)。对于氨氮（NH(4)-N）和总磷（TP），系统平均去除率分别为 69.8%和 54.5%，最终浓度分别为 18.8 ± 9.3 和 14.0 ± 2.5 mg L(-1)。藻类和水生植物共同作用，使 NH(4)-N 的去除率达到 33.6%，TP 的去除率达到 26.4%。除 TP 外，所有参数的最终浓度均达到了巴西和欧盟法规规定的排放阈值。EE 被认为是为其创建目的而设计的。
