So Soil il Mixin ixing De Developmen ent t of of a - PowerPoint PPT Presentation

Reductiv ive dechlo lorin inatio ion via via ir iron based So Soil il Mixin ixing De Developmen ent t of of a sustainable le tech echnique – a reg egional coll ollaborati tion Katerina Hantzi, Capitol Region of Denmark 21. May 2019 - AQUACONSOIL

CROSS BORDER COOPERATION Funding Duration: 1. Sep. 2017- 31. Aug. 2020 • Budget: 1,35 mio . € • EU’s regional development fund Interreg • Öresund-Kattegat-Skagerak: 0,68 mio . € St Stakehol older: 1

COMMON INTERESTS CAPITOL REGION OF DENMARK SW SWEDEN Sites or probable sites contaminated with chlorinated solvents in the ÖKS-region (e.g. The Capitol Region of Denmark, and Skåne, Halland and Västra Götalands counties in Oeresund Sweden). 2

SOIL MIXING ➢ Develop the soil mixing technique regarding chlorinated solvents, ➢ Improve the geotechnical and energy efficiency performance, ➢ Demonstrate the new functions in-situ. 3

SUSTAINABLE SOIL MIXING Full Lab Pilot Scale ➢ Find suitable Fe-additives to reach chemical degradation of TCE : • FeCl 2 • FeCl 2 +magnetit, • S-nZVI • ZVI+ FeSO 4 ➢ Find the right combination of binder components ➢ Optimize recipe to increase the energy efficiency of the method 4

RESULTS - Shear Strength Clay Till 5

RESULTS - Shear Strength FeCl 2 FeCl2 (green) and "Soft Control" (yellow) B.1 B 90 B.2 K.0 80 J.0 I.0 70 I 60 Shear Strength (kPa) J K 50 40 30 20 10 0 0 1 2 3 4 5 6 7 8 Days 6

RESULTS - Shear Strength S-nZVI Shear Strength S-nZVI (green) and "Hard Control" (blue) (kPa) 300 250 F G 200 H 150 Clay Till 100 50 0 0 1 2 3 4 5 6 7 8 Days 7

RESULTS reductive dechlorination Additive: Hard Magnetite + Soft ZVI + Intermediate Contr. FeCl 2 S-nZVI Contr. FeSO 4 Contr. FeCl 2 FeCl 2 Day 0 7 14 34 8

RESULTS – TCE-concentration; Fe-additives 9

RESULTS – Degradation; Fe-additives 10

RESULTS – Degradation rate; T½ in in days T½ in days T½ 17 T½ 11 T½ 2.0 T½ 17 T½ 3.0 T½ 2.3 T½ 17 T½ 3.9 T½ 9.9

OPTIMIZE RECIPE Next xt step in in lab lab: ❑ Continue with S-nZVI ❑ Test high and low concentrations of TCE: 1000 mg TCE /kg soil and 100 mg TCE/ kg soil ❑ Test dose of reactant ❑ Test dose of binder ❑ Test different binders: Cement-slagg: 30-70 (%); 50-50 (%) 12

THANK YOU FOR YOUR ATTENTION QUESTIONS? HÅLLBAR SOIL MIXING

AKNOWLEDGEMENTS Geological Survey of Sweden: Klas las Arn rnerdal & Eri rik Bergstedt Swedish Geotechnical Institute: Da Dary rya Kupry ryia ianchyk, Wilh ilhelm Ra Rankka & Cecili ilia Toomväli i Capitol Region of Denmark: Anna Toft DTU Environment, Denmark: Annika Fjo Fjordbøge Swedish Transport Adm.: Per Lin Lind Our consultants: COWI an and Ge Geosyntec HÅLLBAR SOIL MIXING