Event Title

The Use of Surface Constructed Wetlands for Lagoon Wastewater Treatment

Presenter Information

Ashraf Shaqadan
R. Ryan Dupont

Location

Space Dynamics Laboratory

Event Website

http://water.usu.edu/

Start Date

3-26-2004 10:45 AM

End Date

3-26-2004 11:00 AM

Description

A model free water surface constructed wetland system was used to treat effluent of a wastewater treatment lagoon. Four replicate reactors containing four native plant species and employing soil were designed, built, and operated at the Utah Water Research Laboratory. Several unique but related studies were conducted for 8 months (from March 2000 to January 2001). Water quality parameters (pH, oxidation reduction potential, alkalinity, conductivity, DO, and EC) were monitored. Pollutant (TSS, VSS, NH3, TP, DP, fecal coliform and Total organic carbon) removal efficiencies and rate constants were estimated. Design parameters (water depth, HLR, RT, and evapotranspiration) were investigated. The design parameter, retention time, was evaluated to maximize pollutants removal. Plant biomass production parameters (dry weight, SLA, LAI) were measured. Water quality removals had different patterns as a function of treatment length or retention time. pH and ORP remained steady, alkalinity and conductivity increased, and TSS, VSS, NH3, TP, DO, and DOC were reduced effectively within the first third of treatment length to a background level. Dissolved P indicates a “gradual” reduction with distance. The steady state calculated pollutants removals were; 82% for TSS, 81% for VSS, 93% for ammonia,51% for DOC and 43% for TP. DP had a negative removal efficiency of -25%. Hydraulic loading rates were relatively low with an average of 1.88 ± (0.7) cm/day. The calculated RT averaged 6 days, which is 65% shorter than the design RT of 15 days. ET rates were high with an average of 16.2 mm/day. Normal FC levels were generally low, with an average of 11 CFU/100 mL. FC removal was high with only an average of 2 CFU/100 mL in the effluent. Shock FC load removal rate was 0.716 day-1. The three species Scripus maritimus, Typha latifolia, and Juncus torreyi outperformed Scripus acutus for all reactors. The first half of the reactors was dominated by Typha latifolia ; while Juncus torreyi increased in the second half of the reactors. Estimates of species leaf area Index for the plants were; 19, 3.5, and 5.5 (cm2 leaves/cm2 ground) for Typha latifolia, Scripus maritimus, and Juncus torreyi, respectively.

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Mar 26th, 10:45 AM Mar 26th, 11:00 AM

The Use of Surface Constructed Wetlands for Lagoon Wastewater Treatment

Space Dynamics Laboratory

A model free water surface constructed wetland system was used to treat effluent of a wastewater treatment lagoon. Four replicate reactors containing four native plant species and employing soil were designed, built, and operated at the Utah Water Research Laboratory. Several unique but related studies were conducted for 8 months (from March 2000 to January 2001). Water quality parameters (pH, oxidation reduction potential, alkalinity, conductivity, DO, and EC) were monitored. Pollutant (TSS, VSS, NH3, TP, DP, fecal coliform and Total organic carbon) removal efficiencies and rate constants were estimated. Design parameters (water depth, HLR, RT, and evapotranspiration) were investigated. The design parameter, retention time, was evaluated to maximize pollutants removal. Plant biomass production parameters (dry weight, SLA, LAI) were measured. Water quality removals had different patterns as a function of treatment length or retention time. pH and ORP remained steady, alkalinity and conductivity increased, and TSS, VSS, NH3, TP, DO, and DOC were reduced effectively within the first third of treatment length to a background level. Dissolved P indicates a “gradual” reduction with distance. The steady state calculated pollutants removals were; 82% for TSS, 81% for VSS, 93% for ammonia,51% for DOC and 43% for TP. DP had a negative removal efficiency of -25%. Hydraulic loading rates were relatively low with an average of 1.88 ± (0.7) cm/day. The calculated RT averaged 6 days, which is 65% shorter than the design RT of 15 days. ET rates were high with an average of 16.2 mm/day. Normal FC levels were generally low, with an average of 11 CFU/100 mL. FC removal was high with only an average of 2 CFU/100 mL in the effluent. Shock FC load removal rate was 0.716 day-1. The three species Scripus maritimus, Typha latifolia, and Juncus torreyi outperformed Scripus acutus for all reactors. The first half of the reactors was dominated by Typha latifolia ; while Juncus torreyi increased in the second half of the reactors. Estimates of species leaf area Index for the plants were; 19, 3.5, and 5.5 (cm2 leaves/cm2 ground) for Typha latifolia, Scripus maritimus, and Juncus torreyi, respectively.

https://digitalcommons.usu.edu/runoff/2004/AllAbstracts/25