Abstract
To explore an economical and manageable wastewater treatment process, a full-scale ecology filter integrated constructed rapid infiltration (Eco-CRI) was conducted and applied to treat freeway toll-gate domestic sewage, and the performances of Eco-CRI were investigated to evaluate its technical and economical suitability. The results showed that chemical oxygen demand, suspended solids, ammonia, and phosphorus could be removed efficiently when 1.0
m
d
−1 of the hydraulic loading rate and 2
h of dosing and 6
h of resting of feed regime were operated, respectively. Clogging, which was by far the biggest operational concern for the soil-based treatment systems, was not observed during the whole operation over a period of 14 months. Based on the results of economical analysis, electrical power consumption of per m
3 wastewater treated was only 0.13
kWh. Besides maintenance of dosing pump, regular maintenance of Eco-CRI was just harvesting reeds and earthworms once a year. The facts indicated that Eco-CRI was a cost-effective and technically feasible process for freeway toll-gate domestic sewage treatment, and might serve as an attractive option for wastewater treatment in remote areas where regular maintenance was not feasible and/or in present developing countries like China where uneconomical approaches were not acceptable due to the local socioeconomic situation.