Sawdust for Treatment of Stormwater - Test on Synthetic Stormwater Contaminated with Heavy Metals

Abstract

Stormwater from urban, industrial and rural areas is very often discharged into recipient water bodies without any treatment. This is now changing in many parts of the word, especially in Europe due to The EU Water Framework Directive (European Union, 2000). According to the new policy, will probably stormwater that has often small concentrations but complex mix of different organic and inorganic pollutants has to be treated. Many different systems have been used, such as wetlands and soil infiltration trenches, among others. Sawdust has many times been reported as a good sorbent used for removing mostly toxic metals from wastewaters. However, in most cases, studies have been carried out with distilled water spiked with, for instance, 1-2 different toxic metals. Very few studies have used real wastewater and even less have studied removal of metals from stormwater using sorbent such as sawdust. Sawdust has also drawbacks, since it may release potentially hazardous substances as tannins: lignin, phenolic compounds, resin acids and overall high COD concentrations which results in oxygen depletion in the recipient water bodies. In this paper, the results of using sawdust as sorbent for removal of heavy metal from stormwater with different pollutants are presented.