REMOVAL OF HEAVY METALS IN WATER BY PINE BARK / Reduktion av metaller från vatten genom furubarkflis
Metals that are dissolved in storm water can be removed by filtrating water through specially constructed filter systems. Pine bark is an interesting material for this purpose, but it needs further investigations regarding its removal efficiency of metals. This paper presents a laboratory study where pine bark was tested to evaluate its efficiency in reducing heavy metals in water. Metal solutions were prepared and used in batch tests with pine bark. The metal removal efficiency was correlated to different metal concentrations in the solution and different contact times between the pine bark and the metal solution. The results showed that a high metal removal was achieved after a short contact time. The metal removal was low for low metal concentrations (0.1 mg/L) and higher for metal concentrations from 1 to 10 mg/L. The removal capacity was found to be 2.6 g Cu, 1.3 g Zn and 3.8 g Pb per kg pine bark. An investigation of the influence of chloride in the metal solution showed that the metal removal decreased by 15-23 %, depending on the metal, in the presence of chloride. Sorption isotherms of Zn, Cu and Pb on pine are also presented in the paper.