A pilot plant for the electrodialytic remediation of CCA-treated waste wood has been developed and tested at the Technical University of Denmark. Results from two experiments with different amount of wood chips are presented here. Prior to the electrodialytic remediation the wood was soaked in oxalic acid and phosphoric acid. The main purpose of soaking is to remove the most available fraction first and then use the electric current to remove the less available fractions. This proved successfully as the majority of CCA could be removed by soaking. The highest overall removal was obtained in an experiment with 100 kg wood chips. The electrode distance was 60 cm and 87% Cu, 81% Cr and >95% As was removed. In an experiment with 250 kg wood and an electrode distance of 150 cm, the removal of Cu and Cr was significantly lower, both below 60%. This is presumed to be due to the limitations of the power supply used. In the same experiment 96% As was removed, indicating that As is the easiest removable of the three CCA components. This result is very encouraging since As is the component of most environmental concern.

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