Dissolved Organic Carbon and Copper Speciation in Compost-Amended - PowerPoint PPT Presentation

Dissolved Organic Carbon and Copper Speciation in Compost-Amended Bioretention Systems Markus Flury, Jessica Mullane, Maninder Chahal, Zhenqing Shi Department of Crop and Soil Sciences Washington State University Markus Flury (WSU) Leaching from Compost WSC 2019 Review 1 / 26

Introduction Outline Introduction 1 Methods 2 Results 3 Conclusions 4 Markus Flury (WSU) Leaching from Compost WSC 2019 Review 2 / 26

Introduction Bioretention Systems What are the impacts of widespread use of compost in bioretention systems? native plants filter strip water flow compost impervious retention surface zone bioretention soil mix Source: LID Manual for Puget Sound, 2012 Markus Flury (WSU) Leaching from Compost WSC 2019 Review 3 / 26

Introduction Bioretention Systems What are the impacts of widespread use of compost in bioretention systems? - Dissolved organic carbon (DOC) - Copper (Cu) native plants filter strip water flow compost impervious retention surface zone bioretention soil mix Source: LID Manual for Puget Sound, 2012 Markus Flury (WSU) Leaching from Compost WSC 2019 Review 4 / 26

Methods Outline Introduction 1 Methods 2 Results 3 Conclusions 4 Markus Flury (WSU) Leaching from Compost WSC 2019 Review 5 / 26

Methods Column Setup Markus Flury (WSU) Leaching from Compost WSC 2019 Review 6 / 26

Methods Compost Markus Flury (WSU) Leaching from Compost WSC 2019 Review 7 / 26

Methods Compost Feedstock: Food waste: 1-20% Yard waste: 80-99% Age: 6 and 24 months Markus Flury (WSU) Leaching from Compost WSC 2019 Review 8 / 26

Methods Leachate Markus Flury (WSU) Leaching from Compost WSC 2019 Review 9 / 26

Methods Irrigation and Sample Analysis Irrigation 6-months 24-hour storm 33 mm/day intermittend, every two weeks 18 storms Leachate Analysis pH, EC, DOC Nitrate, Nitrite, org. N Phosphorus, Cu (total and dissolved) Particulates < 0.45 µ m 0.45 - 1 µ m 1 - 11 µ m > 11 µ m Markus Flury (WSU) Leaching from Compost WSC 2019 Review 10 / 26

Methods Chemical Speciation Modeling Model Visual MINTEQ Model Input Stormwater chemistry Leachate chemistry Model Output Cu species Markus Flury (WSU) Leaching from Compost WSC 2019 Review 11 / 26

Results Outline Introduction 1 Methods 2 Results 3 Conclusions 4 Markus Flury (WSU) Leaching from Compost WSC 2019 Review 12 / 26

Results Dissolved Organic Matter 1200 1200 7 7 Dissolved Organic Matter Electrical Conductivity 6 6 1000 1000 Replicate 1 EC (mmhos/cm) 5 5 Replicate 2 DOC (mg/L) 800 800 Replicate 3 4 4 600 600 3 3 400 400 2 2 Replicate 1 Replicate 2 200 200 Replicate 3 1 1 0 0 0 0 0 1000 2000 3000 4000 5000 6000 0 1000 2000 3000 4000 5000 6000 Cumulative Leachate Flux (mm) Cumulative Leachate Flux (mm) Markus Flury (WSU) Leaching from Compost WSC 2019 Review 13 / 26

Results Copper Concentration ( μ g-Cu/L) 140 Copper 120 6 month 6 month 100 * * 24 month 24 month 80 * 60 40 20 0 1 2 3 4 5 6 8 12 18 Storm Number Markus Flury (WSU) Leaching from Compost WSC 2019 Review 14 / 26

Results Copper Concentration (μg-Cu/L) 140 Copper 120 discharge limit for 100 * industrial activities * 80 * 60 40 20 0 1 2 3 4 5 6 8 12 18 Storm Number Markus Flury (WSU) Leaching from Compost WSC 2019 Review 15 / 26

Results Surface Complexation Markus Flury (WSU) Leaching from Compost WSC 2019 Review 16 / 26

Results Surface Complexation Activities Metal ion (i.e., Cu) Monodentate Complex Apparent equilibrium constant Sorbent functional group (i.e., DOC) Bidentate Complex Markus Flury (WSU) Leaching from Compost WSC 2019 Review 17 / 26

Results Surface Complexation Activities Metal ion (i.e., Cu) Monodentate Complex Apparent equilibrium constant Sorbent functional group (i.e., DOC) Bidentate Complex Markus Flury (WSU) Leaching from Compost WSC 2019 Review 18 / 26

Results Copper Speciation Total inorganic Cu species Free Cu (Cu 2+ ) Total organically complexed Cu Copper organic bidentate complex Species distribution (%) 100 80 2+ 60 pH = 7 [Cu_tot] = 28 µ g/L 40 20 0 10 2 10 1 10 0 10 1 10 2 10 3 DOC (mg/L) Markus Flury (WSU) Leaching from Compost WSC 2019 Review 19 / 26

Results Copper Speciation 2+ + + Cu , CuOH , Cu(OH) , CuCO , CuCl 2 3 Total inorganic Cu species Free Cu (Cu 2+ ) Total organically complexed Cu Copper organic bidentate complex Species distribution (%) 100 80 2+ 60 pH = 7 [Cu_tot] = 28 µ g/L 40 20 0 10 2 10 1 10 0 10 1 10 2 10 3 DOC (mg/L) Markus Flury (WSU) Leaching from Compost WSC 2019 Review 20 / 26

Results Copper Speciation Total inorganic Cu species at 100 mg/L DOC Total inorganic Cu species Total organically complexed Cu species at 100 mg/L DOC Free Cu (Cu 2+ ) Total toxic inorganic Cu species at 0.1 mg/L DOC Total organically complexed Cu CuCO 3 (aq) at 0.1 mg/L DOC Copper organic bidentate complex Total organically complexed Cu species at 0.1 mg/L DOC Species distribution (%) 100 100 C 80 80 O D 60 60 t n e u 40 l 40 f f E 20 20 0 0 10 2 10 1 10 0 10 1 10 2 10 3 6 7 8 pH DOC (mg/L) Markus Flury (WSU) Leaching from Compost WSC 2019 Review 21 / 26

Results Copper Speciation Total inorganic Cu species at 100 mg/L DOC Total inorganic Cu species Total organically complexed Cu species at 100 mg/L DOC Free Cu (Cu 2+ ) Total toxic inorganic Cu species at 0.1 mg/L DOC Total organically complexed Cu CuCO 3 (aq) at 0.1 mg/L DOC Copper organic bidentate complex Total organically complexed Cu species at 0.1 mg/L DOC Species distribution (%) 100 100 organic Effluent DOC 80 80 60 60 40 40 20 20 inorganic 0 0 10 2 10 1 10 0 10 1 10 2 10 3 6 7 8 pH DOC (mg/L) Markus Flury (WSU) Leaching from Compost WSC 2019 Review 22 / 26

Results Copper Speciation Total inorganic Cu species at 100 mg/L DOC Total inorganic Cu species Total organically complexed Cu species at 100 mg/L DOC Free Cu (Cu 2+ ) Total toxic inorganic Cu species at 0.1 mg/L DOC Total organically complexed Cu CuCO 3 (aq) at 0.1 mg/L DOC Copper organic bidentate complex Total organically complexed Cu species at 0.1 mg/L DOC Species distribution (%) 100 100 organic Effluent DOC 80 80 inorganic 60 60 40 40 organic 20 20 inorganic 0 0 10 2 10 1 10 0 10 1 10 2 10 3 6 7 8 pH DOC (mg/L) Markus Flury (WSU) Leaching from Compost WSC 2019 Review 23 / 26

Results Copper Speciation Activity of free Cu Percentage of Cu pCu = −log {Cu} complexed with DOC Cu-DOM (%) pCu 10 8.5 100 8.5 [DOC]/[Cu] (g DOC/mmol Cu) Effluent 16 Effluent 8.0 8.0 80 7.5 14 7.5 60 7.0 7.0 12 pH pH 6.5 6.5 Inflow Inflow 40 10 6.0 6.0 20 8 5.5 5.5 5.0 0 5.0 6 10 -1 10 0 10 1 10 2 10 3 10 -1 10 0 10 1 10 2 10 3 [DOC]/[Cu] (g DOC/mmol Cu) [DOC]/[Cu] (g DOC/mmol Cu) Markus Flury (WSU) Leaching from Compost WSC 2019 Review 24 / 26

Conclusions Outline Introduction 1 Methods 2 Results 3 Conclusions 4 Markus Flury (WSU) Leaching from Compost WSC 2019 Review 25 / 26

Conclusions Conclusions native plants filter strip water flow compost impervious retention surface zone bioretention soil mix EC, DOC, and particulates decreased over the course of an individual storm Markus Flury (WSU) Leaching from Compost WSC 2019 Review 26 / 26

Conclusions Conclusions native plants filter strip water flow compost impervious retention surface zone bioretention soil mix EC, DOC, and particulates decreased over the course of an individual storm Each individual storm mobilizes constituents with increased concentrations Markus Flury (WSU) Leaching from Compost WSC 2019 Review 26 / 26

Conclusions Conclusions native plants filter strip water flow compost impervious retention surface zone bioretention soil mix EC, DOC, and particulates decreased over the course of an individual storm Each individual storm mobilizes constituents with increased concentrations DOC from compost effectively complexes inorganic Cu Markus Flury (WSU) Leaching from Compost WSC 2019 Review 26 / 26

Conclusions Conclusions native plants filter strip water flow compost impervious retention surface zone bioretention soil mix EC, DOC, and particulates decreased over the course of an individual storm Each individual storm mobilizes constituents with increased concentrations DOC from compost effectively complexes inorganic Cu Cu-DOC complexation is an equilibrium process Markus Flury (WSU) Leaching from Compost WSC 2019 Review 26 / 26