Investigation of humic acid from sewage sludge of Diyarbakjir and examination in view of chemical analysis

The wastewater sludge obtained during the treatment of the water to be used as drinking water is disposed of with various methods. However, these sludges are also known to contain high amounts of organic material and valuable components such as humic acid and fulvic acid. Within the scope of the thesis, humic acid was obtained from wastewater treatment sludge obtained from Diyarbakır Metropolitan Municipality, Water and Sewage Administration, Waste Water Treatment Plant. In this scope, the basic extraction process applied to the solids from the samples obtained from 6 different points in the process, 3 of which were liquid and 3 of them as solid sludge. Chemical structures of the obtained humic acids were investigated by FT-IR. In order to demonstrate the potential for agricultural use, Pb, Cd, Cr, Cu, Ni, Zn and Hg concentrations of humic acids were measured by ICP-OES after digestionby microwave oven. When the results were evaluated, the amount of humic acid (pre-decay), decayed sludge (pre-decanter) and the amount of humic acid in stabilized sludge were determined as %3.5, %2.8 ve %3.2 for the samples that oxidation did not applied,the amount of humic acid (pre-decay), decayed sludge (pre-decanter) and the amount of humic acid in stabilized sludge were determined as %30, %20 ve %4.8 for the samples that oxidation applied. When the results of ICP-OES analysis are taken into consideration, it is seen that humic acids obtained from wastewater treatment sludge are below the limit values of Pb, Cd, Cr, Cu, Ni, Zn and Hg and humic acids can be used for agricultural purposes.