Oily sludge (OS) contains toxic compounds such as aromatic hydrocarbons and polyaromatic hydrocarbons; oily sludge is hard to dehydrate due to its high viscosity. Generally, it contains about (40 to 50 wt.%) of water. However, this research's oily sludge sample contains about (50 wt.%) of water collected from North Refineries Company Baiji (NRC). NRC Baiji yields around 3000-3500 m3 annually of oily sludge. This research aims to study oily sludge specifications, thereby prove suitability to undergo the thermochemical process. The physical properties of oily sludge samples have been conducted, it indicated the complex formula of oily sludge, and it has a serious effect on human health and environmental issues. In this study, the oily sludge has a low heating value (LHV) of 6.705 MJ.kg-1 (as received) and a high heating value (HHV) of 9.465 MJ.kg-1 for a dried sample at 105 °C for 24 h, which indicate that it is a rich in carbon content. FTIR has been carried out to obtain the function group characterizations. The TGA of the oily sludge sample as received showed the greatest loss in volume (39%), while the loss in volume for the dried sample was (15%). The thermochemical conversion process eco-friendly, rapid, short time, moderate temperature, and low-cost. It is used for the total reclamation of waste. It is a novel way of totally converting oily sludge for solid carbon fuel production.