The separation of
oil components from oily sludge is an important
component of soil remediation and energy recovery. Therefore, establishing
a green and efficient separation technology is of great significance.
In this study, oily sludge was separated using sodium lignosulfonate
(SL) treatment. The effects of temperature, SL concentration, rotate
speed, time, and pH on the oil removal rate were studied. The optimal
conditions were as follows: temperature, 30 °C; SL concentration,
2.0 g·L–1; rotate speed, 200 rpm; time, 60
min; and pH 11. The maximum oil removal rate was 83.21%. The physicochemical
properties of oily sludge were analyzed. The soil was looser, and
the contact angle (55°) of the soil surface was reduced. Alkanes,
aldehydes, ketones, carbonic acids, benzene rings, and alicyclic ethers
were removed. The result shows that the SL treatment removed a wider
range of petroleum hydrocarbon and had a stronger oil removal capacity.
It provides a new method for the green and efficient separation of
oily sludge.