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Organic compounds in concrete from demolition works
M Van Praagh1, H Modin2, J Trygg3
1Sweco Environment, Drottningtorget 14, 201 22 Malmö, Sweden; Centre for Environmental and Climate Research, Lund University, Lund, Sweden.
Waste Management (New York, N.Y.)
|July 13, 2015
Summary
Physically removing contaminated concrete surfaces can reduce pollutants below recycling guidelines. However, leaching tests show potential environmental risks when recycled, requiring further evaluation.
Area of Science:
- Environmental Science
- Civil Engineering
- Geochemistry
Background:
- Industrial concrete sites often contain pollutants like polycyclic aromatic hydrocarbons (PAH) and pesticides.
- Recycling contaminated concrete requires assessing pollutant levels and mobility.
Purpose of the Study:
- To evaluate the effectiveness of surface removal in reducing concrete contaminants.
- To assess the potential mobility of pollutants in recycled concrete through leaching tests.
Main Methods:
- Analysis of reclaimed concrete from three Swedish industrial sites.
- Batch and column leaching tests to determine pollutant mobility.
- Chemical analysis for metals, Cl, F, SO4, DOC, PAH, and pesticides.
Main Results:
- Surface removal (1-5 mm) reduced PAH concentrations below Swedish recycling guidelines.
- Most pesticide-contaminated samples met soil guidelines after surface treatment.
- Leaching tests indicated potential exceedances of environmental quality standards for PAH and phenoxy acids in recycled concrete.
Conclusions:
- Surface removal is a viable method for reducing certain contaminants in concrete for recycling.
- Leaching potential of remaining pollutants needs careful consideration for safe recycling.
- Further research is needed to validate leaching test results and equipment impact.
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