Removing of polycyclic aromatic hydrocarbons by constructed wetlands

Abstract

Constructed wetlands are a natural alternative to conventional methods of treatment of contaminated water and soil, which are based on complex processes involving plants, microorganisms, soil matrix and pollutants. It is well known that these synergistic interactions contribute significantly to the removing of inorganic contaminants from the environment. An understanding how plants, microorganisms, the soil bed and pollutant, interact with each other at the contaminated place, is still rather incomplete, especially in the case of organic contaminants. However, some small scale process modeling experiments, which currently have been developed for polycyclic aromatic hydrocarbons (PAHs) removing, show that the active reaction zone of constructed wetlands is the root zone (or rhizosphere). There are numerous different technological variants in terms of design of constructed wetlands, peripheral equipment, etc., but usually, they are mainly distinguishable by the type of the soil bed and applied plant. The most suitable system can be adapted to specific waste problems and local conditions.