Sludge drying with application of phragmites australis reed

Application of reed gives good results of drying and mineralization of sewage sludge. The output of this method depends on plants condition. Sludge overflowed on reed plots are characterized by high hydration up to 99% and high content of organic matter up to 70% of dry mass may cause prolonged hypoxemia and atrophy of reed, what causes decrease of drying process. Research conducted on plots reeds situated on the terrain of mechanical and biological sewage treatment plant in Swarzewo, Pomorskie province showed, that overflowing of sludge at regular intervals is better for the growth of reed as well as for the sludge drying. Overflowing with sludge caused activation by reeds of defence system against lack of oxygen in the soil. Adaptation of reed consisted in increase of oxygen amount by individual blades as well as their bigger mass in 1 m. Increased production of oxygen and therefore increased transport to underground parts (rhizomes and roots) on stands overflowed with sewage sludge was possible thanks to increase of assimilation apparatus, what is proved by high share of leafs in shoots biomass and their big surface. Increase of leafs surface in comparison with plants from control stands made also possible intensification of water exchange by evaporation and transpiration.