The pollutant elimination performance and bacterial communities of unpowered baffle rural sewage reactor filtered with construction wastes

Sewage and construction waste in rural areas are urgently needed to be effectively treated with low cost as the higher environmental demand and lower economic level in rural areas. In this study, unpowered baffle rural sewage reactors filtered with different construction wastes, autoclaved aerated concrete (ALC), composite mortar (CM), and red brick (RB), were established and operated to achieve the cooperative governance of rural sewage and rural construction wastes. The pollutant removal effect and bacterial communities were revealed and the mechanism of pollutant removal caused by construction wastes was discussed. Unpowered baffle rural sewage reactors filtered with construction wastes had evident removal effect on COD (31.57%-55.07%) and SS (27.57%- 41.36%) during the 3 h retention time and cement based construction wastes (ALC and CM) showed evident TP removal effect (16.71%-35.26%). The bacterial communities of construction wastes (e.g. Chlorobium, Coma-monas, and Acinetobacter) were complex and differed with waste type. However, the pollutant removal related functions of the bacteria on different construction wastes were similar. The different pollutant removal effect of construction wastes was mainly caused by their physicochemical characteristics, but not their bacterial com-munity characteristics. ALC and RB can be used to COD removal, CM can be used to SS removal, and ALC and CM can be used to TP removal in rural sewage treatment. Overall, this study provided an effectively and low-cost method to co-governance of rural sewage and rural construction wastes which is suitable for rural areas and has development potential.

Automated summary

In this study, unpowered baffle rural sewage reactors were established and operated with different construction wastes to achieve the cooperative governance of rural sewage and rural construction wastes. The results showed that the construction wastes had a significant removal effect on COD and SS, and the different removal effects were mainly influenced by their physicochemical characteristics rather than bacterial community characteristics. This study provided an effective and low-cost method for the co-governance of rural sewage and rural construction wastes, which is suitable for rural areas and has development potential.