The invention discloses a method for comprehensive treatment of oily
sludge based on a hydrothermal technology. The method mainly relates to two parts, namely hydrothermal extraction and hydrothermal oxidation. The method comprises the following steps: firstly, extracting most of
oil type organic matters in the oily
sludge by adopting a hydrothermal extraction method, and recovering the
oil type organic matters by virtue of an oil-water separator; secondly, oxidizing, degrading and eluting non-
oil type organic matters in residues after extraction by adopting a hydrothermal oxidation method, performing advanced treatment on generated
wastewater and
wastewater after extraction together, and discharging the
wastewater after the wastewater reaches standard; and finally, performing up-to-standard release or
resource utilization on
solid residues. According to the method disclosed by the invention, high-temperature high-pressure water is used for performing non-polar extraction and
recovery on the oil type organic matters, and killing all
pathogenic bacteria in the oil type organic matters, treated
effluent and residues are further treated or subjected to
resource utilization, and then a treatment target of reduction, harmlessness and
resource utilization of the oily
sludge is further achieved.