If the oil sludge discharged from oil sludge treatment is directly discharged without treatment, it will not only occupy a large amount of land, but also contain a large amount of heavy metals and bacteria, which will produce foul odors and cause serious pollution of water, soil and atmosphere.

At present, there are many treatment technologies for oily sludge, in accordance with the requirements of reduction, harmlessness, resource utilization and comprehensive utilization.

The main treatment methods of oily sludge waste in oilfields are as follows:

1. Incinerate in a high temperature incinerator. Oilfields often use thermal desorption unit (TDU). The sludge is incinerated to recover clean oil and water, and the oil content in the solid waste is reduced to less than 0.5%. The products that meet the standard will be landfilled or fired bricks. This treatment method is costly and causes coking, which affects the normal operation of the incinerator. And energy cannot be recovered efficiently. If the oily sludge has a high moisture content, the temperature in the incinerator will decrease after entering the incinerator, and the pollutants after incineration will not be able to reach the standard stably, which will lead to air pollution and dust pollution.

2. Treat oily sludge by drying ordinary sludge. Because of the particularity of oily sludge, common processes and machines are not suitable for the treatment of oily sludge, which leads to agglomeration and coking of oily sludge in the equipment, making the equipment scrapped. In addition, the oily sludge treated by the ordinary sludge drying process cannot meet the standard. For example, equipment such as rotary kiln sludge dryers will form coking inside the equipment in a short period of time during the process of processing oily sludge, causing the equipment to fail to operate normally.

3. GN Solids Control Use chemical hot washing to treat and recycle oily sludge. As far as China’s current situation is concerned, chemical hot washing is mostly used for oil recovery from oil sludge, with the purpose of recovering oil. Therefore, the oil sludge after hot washing is a non-standard product and still needs to be treated. Therefore, the hot washing method can only be used as an auxiliary method for reduction, and cannot be used as a direct oil sludge treatment method.