The study presents an analysis of temperature change and dry matter content in sludge resulting from autothermal thermophilic stabilization process (ATAD), referring to selected sewagetreatment plants. The first in Poland ATAD installation manufactured by FUCHS, GAS und WASSERTECHNIK Mayen-Deutschland and functioning at SZCZECIN-SKOLWIN S.A. papermill and in Bystry has been presented, also, the study describes the first use of the installation at municipal sewage-treatment plant in Giżycko. Sewage disposal affects the Baltic basin. The study of the mentioned sewage-treatment plants was conducted in the years 2004-2009. The temperature of processed sludge and the dry matter content in collected samples were continuously measured at both plants. The collected data is subjected to an analysis which enables us to assess the effectiveness of the process when used to generate full value fertilizer. There is conclusion stemming from the study and own experience of the described installation exploitation.