Senior Design 2020 – Environmental Engineering Team 3
Environmental Engineering Team 3
Olivia Harris Enita Liang Jing Ling Ziyan Zhang
On-Site Wastewater Treatment for Mansfield Four Corners
Hop Knot and Toast are restaurant establishments that are required to manage their wastewater. The waste generated consists of nutrient and solids loadings which include biochemical oxygen demand (BOD), total suspended solids (TSS), nitrogen, phosphorus, and fats/oil/grease (FOG) that must be treated. Although naturally occurring in the ecosystem, discharging highly concentrated contaminated effluents can cause severe ecological harm. The proposed solution is to design an on-site treatment system for the effluent from Mansfield Four Corners restaurants.
In this project, we provided two solutions for wastewater treatment: a septic system with either a leaching field or a subsurface constructed wetland. Both solutions involve primary and secondary treatment. In primary treatment, the wastewater will first go through a grease interceptor and then a septic tank for settling that removes the majority of FOGs and solids. For secondary treatment, the traditional leach field removes phosphate, metal ions, and TSS in the soil but can only remove a small portion of nitrogen. The alternative solution was a vegetated submerged bed wetland which uses microorganisms and vegetation to promote nutrient and organic contaminant removal.