Method for adding water to oil-containing sludge and centrifugally removing oil

The invention relates to the technical field of waste pollutant cleaning in the petroleum industry, in particular to a method for centrifugally removing oil from oily sludge by adding water. The method provided by the invention comprises the following steps: pretreating the oily sludge to obtain a pretreated solid phase and a pretreated liquid phase; the pretreatment comprises the following steps: sequentially carrying out first mixing and solid-liquid separation on the pretreated oil and the oily sludge; the pretreated solid phase and water are mixed for the second time and then centrifuged to remove oil, the centrifuging speed is 1000-9000 rpm, and the time is 5-10 min; the pretreated oil comprises isoparaffin solvent oil, kerosene or a sodium dodecyl benzene sulfonate oil solution; a solvent of the sodium dodecyl benzene sulfonate oil solution comprises isoparaffin solvent oil or kerosene. According to the method, organic matters insoluble in an oil phase in the oily sludge are stripped from solid-phase pa