Migration Activity of Heavy Metals During Pyrolysis of Dried Sewage Sludge in a Fixed-Bed Reactor

The results of a study of the pyrolysis of dried sewage sludge taken from a fixed-bed reactor of urban wastewater treatment plants are presented. The obtained experimental data made it possible to estimate the migration activity of heavy metals entering into the composition of the sewage sludge. Measurements were carried out for vanadium (V), chromium (Cr), cobalt (Co), nickel (Ni), copper (Cu), zinc (Zn), strontium (Sr), lead (Pb), rubidium (Rb), barium (Ba), zirconium (Zr), and arsenic (As). It is shown that the emission of heavy metals upon release of volatile substances during pyrolysis is characteristic for almost all of the studied elements, among which As, Rb, Co, and Ba are the elements having the highest migration activity.