Pyrolysis of sewage sludge by solid heat carrier

Abstract

The experimental study of fast pyrolysis of dried sewage sludge in the retorting system with solid heat carrier was performed. The yield of the main pyrolysis products such as gas, oil, pyrogenic water, and solid residue (pyrolytic char) was measured in the 490-580 °C range. The maximum oil yield in an amount of 38.5 wt% on dry ash free basis was registered at a temperature of 550 °C. The gas chromatographic-mass spectrometric (GC-MS) analysis of pyrolytic oil allows the identification of 58 hydrocarbons of different structures and different classes such as aliphatic, aromatic, oxygenated and nitrogen-containing compounds. The group composition of the obtained oil makes it possible to identify it as an analog of crude oil, which can be processed by standard technologies. The technological scheme of the facility for pyrolysis of sewage sludge based on the technology Galoter for the thermochemical processing of low-grade fuels was proposed with corresponding material and heat balance.

Keywords: Galoter technology; Pyrolitic oil composition; Pyrolysis products yields; Sewage sludge pyrolysis; Solid heat carrier.