Gasification of Sewage Sludge in a Bench-scale Reactor

Abstract

The handling of sewage sludge is one of the most significant issues of wastewater treatment plant due to its potential harmful environmental impact and remarkable disposal costs. As a consequence, a proper handling of this biowaste is needed. In the present study, a bench-scale fixed bed gasifier was operated with a sewage sludge coming from a drying facility. The experimental runs have been carried out using for each test 30 g of dried sewage sludge, steam as gasifying agent and by varying the reactor temperature in the range of 700 – 850 °C. The results indicated that the gasification test conducted at a temperature of 700 °C produced the highest concentration of hydrogen, 58.2%. In addition, the increase of reaction temperature determined a reduction of char and tar from 11.4 to 9.7 g and from 9.1 to 0.7 g, respectively. On the other hand, the cold gas efficiency increased from 11 to 50%.