Sewage sludge is the by-product of human activities, and incineration is one of the effective disposal technologies for the minimization and utilization of sludge. Hydrothermal carbonization of sludge, as a kind of pretreatment, is of great important for incineration. In order to upgrade the sludge, the effects of hydrothermal temperature, holding time and solid-to-liquid ratio on the fuel property of sludge were studied in single factor experiments. Subsequently, response surface methodology was used to optimize the conditions of hydrothermal process and the calorific value of hydrothermal sludge was used as an evaluation index. The results indicated that the optimum conditions were hydrothermal temperature of 208.65oC, holding time of 16.82 min and solid-to-liquid ratio of 12.31%. Among these conditions, the optimum calorific value of hydrothermal sludge was 4207 J/g. Furthermore, the verification experiment showed that the actual calorific value of hydrothermal sludge prepared via above conditions was 4203±24 J/g, which was basically consistent with the results of response surface methodology. Moreover, more than 65% energy could be cut down via hydrothermal treatment when comparing with traditional thermal.
ZHUANG Xiu-zheng
,
HUANG Yan-qin
,
YIN Xiu-li
,
WU Chuang-zhi
. Optimization of Hydrothermal Process for Solid Fuel Derived from Sewage Sludge by Response Surface Methodology[J]. Advances in New and Renewable Energy, 2017
, 5(5)
: 325
-332
.
DOI: 10.3969/j.issn.2095-560X.2017.05.001
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