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Living Machine (LW) was principle technology in the treatment of source-separated blackwater for resource recovery. In this study, three Living Machine (LM) systems planted with different phytocoenoses were operated in parallel to investigate the removal performance of blackwater from septic tank. Higher removal efficiency of turbidity, COD, NH4+-N, TN, and TP of 98.2%, 88.7% 86.5%, 61.2%, and 41.3%, respectively, was obtained in system 1. The floristics with better tolerance and reduction capacity of blackwater in five tanks were listed as follows: Canna indica L., Cyperus alternifolius, and Arundo donax var. versicolor Stokes of tank 3; Polygonum chinense L., Scirpus validus Vahl, Pontederia cordata L., Setcreasea pallida, and Hydrocotyle chinensis (Dunn) Craib of tank 4; and Myriophyllum verticillatum L. and Spirodela polyrhiza (L.) Schleid. of tank 5. Overall, the LM system with suit plant groups offered a more sustainable and economical solution for treating blackwater.

Discharge of wastewater containing nitrogen and phosphate can cause eutrophication. Therefore, the development of an efficient material for the immobilization of the nutrients is important. In this study, a low calcium fly ash and high calcium fly ash were converted into zeolite using the hydrothermal method. The removal of ammonium and phosphate that coexist in aqueous solution by the synthesized zeolites were studied. The results showed that zeolitized fly ash could efficiently eliminate ammonium and phosphate at the same time. Saturation of zeolite with Ca2+ rather than Na+ favored the removal of both ammonium and phosphate because the cation exchange reaction by the NH4+ resulted in the release of Ca2+ into the solution and precipitation of Ca2+ with PO43− followed. An increase in the temperature elevated the immobilization of phosphate whereas it abated the removal of ammonium. Nearly 60% removal efficiency for ammonium was achieved in the neutral pH range from 5.5 to 10.5, while the increase or decrease in pH out of the neutral range lowered the adsorption. In contrast, the removal of phosphate approached 100% at a pH lower than 5.0 or higher than 9.0, and less phosphate was immobilized at neutral pH. However, there was still a narrow pH range from 9.0 to 10.5 favoring the removal of both ammonium and phosphate. It was concluded that the removal of ammonium was caused by cation exchange; the contribution of NH3 volatilization to immobilization at alkaline conditions (up to pH level of 11.4) was limited. With respect to phosphate immobilization, the mechanism was mainly the formation of precipitate as Ca3(PO4)2 within the basic pH range or as FePO4 and AlPO4 within acidic pH range.