Removal of phosphorus from secondary effluents using infiltration–percolation process

Abstract

Intermittent infiltration-percolation is an extensively used treatment process which is capable of oxidizing and decontaminating wastewater. The main purpose of this study was to evaluate the efficiency of this treatment process regarding particularly the removal of phosphorus from urban wastewater effluents. The phosphorus removal mechanisms that may occur in sand filters were investigated. Results confirmed that infiltration-percolation is performed as an advanced treatment technique for suspended solids, organic matter and nitrogen. However, it is less efficient concerning the reduction of orthophosphate. The experimental study has shown the influence of the filter depth, the hydraulic load and its fractionation on phosphorus removal. Analyses of the percolating water sampled at 50, 100 and 150 cm bed depths showed that efficiency of phosphorus removal increased significantly with the depth of the filtering medium. Results indicated that providing more and smaller sequences improves the efficiency of orthophosphate retention. During the experimentation period, phosphorus removal rates do not seem to be affected by the variation of temperature. The scatter plots and the Pearson's correlation coefficient indicate that there is no apparent linear pattern between orthophosphate retention rates and temperature. This finding confirms that phosphorus removal is not attributed to microbial uptake but it is mainly governed by physical-chemical mechanisms such as adsorption and precipitation.

Irrigation with Treated Wastewater as an Alternative Nutrient Source (for Crop): Numerical Simulation

“…As in the case of ammonia nitrogen, a significant reduction in TP concentration can be observed in the course of infiltration through the soil profile. From the measured values, it is possible to reveal the dependence of the output concentration on the depth of the soil layer, as evidenced by the results of the authors [56]. In their study, the PO4-P removal efficiency averaged around 64% for a daily hydraulic load of 0.27 m 3 /m 2 and 63% for a hydraulic load of 0.40 m 3 /m 2 .…”

“…Effective ammonia removal in permeable filter media can be observed with expectation for sand filters. Examples include up to 92% efficiency in the summer season [56], or the inlet concentration of 39 mg/L being reduced to 2.4 mg/L at a depth of 150 cm. Irrigation with pre-treated wastewater proved to be effective in our case as well.…”

Performance evaluation and modelling of an integrated municipal wastewater treatment system using neural networks

“…The particulate phosphorus is physically removed by filtration on the surface of the sand filter’s bed. Dissolved phosphorus is removed by biological or physical–chemical processes (Bali and Gueddari, 2019). The changes in TP concentration and TP removal efficiencies after various steps in the integrated system are shown in Fig.…”

Adsorptive Removal of Phosphate From Wastewater Using Ethiopian Rift Pumice: Batch Experiment

“…10 In conventional biological wastewater treatment, phosphate removal efficiency usually does not exceed 30%. The effluent quality remains high above discharge standard limits 10,11 that demands further treatment by integrating with other removal techniques. In general, conventional wastewater treatment plant effluent consists of about 3 to 4 mg/L of total phosphorous, of which phosphate comprises 70% to 90%.…”

“…Therefore, this batch adsorption study was conducted using synthetic solutions as well as effluents from a secondary treatment unit of a municipal wastewater treatment plant. The study aimed at determining the sorption capacity of phosphate onto pumice; identifying optimum design parameters, such as contact time (5-120 minutes), pH (3)(4)(5)(6)(7)(8)(9)(10)(11)(12), adsorbent dose (2-50 g/L), particle size (<0.075-4.75 mm), initial phosphate concentration (0.5-20 mg/L), competing anions (10-100 mg/L), and agitation speed (100-250 r/min); and evaluating the regeneration and reusability potential of pumice for practical application.…”