Waste oil is produced in petroleum in oil production, pipeline transportation, oil-gas combined stations, oil refineries, and oily wastewater.
Waste oil treatment is a complete set of production process, using the principle of centrifugal separation and oxidation of demulsification. Its main equipment is composed of dosing system, feeding system, separation system, conveying system, and control system.
After the waste oil is collected and heated by steam, a suitable number of additives like demulsifier and active agent are added in it, make the emulsified oily water become liquid.
A high-efficiency three-phase used oil centrifuge is adopted to realize the continuous separation of oil, water, and slag in the oily sludge.
The separated water and oil-water mixture which is not demulsified are directly sent to the sewage treatment system, and a two-phase waste oil centrifuge with high efficiency is used for dehydration.
The crude oil residue in the dehydrated slag phase can be recovered by the combustion or thermal desorption process. The separated crude oil is collected and then purified by a three-phase disc separator. The purified oil can be reused.
The waste oil centrifuge can also handle the oily (waste) water produced during processing crude oil. It is used to treated by rough flocculation + dehydration. The slag phase is directly incinerated after dehydration.
This treatment mode causes a lot of waste of crude oil resources. Now we can apply a series of pretreatment processes (adding demulsifier, surfactant, etc.) and use the high-efficiency three-phase waste oil centrifuge to realize the reuse of crude oil resources.
After the oily (waste) water is collected, add a suitable amount of demulsifier and an active agent., the oily water in the emulsified state turn into liquid, and the oily (waste) water after demulsification is naturally settled and separated in an oil trap.
The water and the oil-water mixture which is not demulsified in the middle layer of the oil trap are directly sent to the sewage treatment system for treatment.
A high efficiency two-phase waste oil centrifuge is used for dehydration. The oil floating on the upper layer of the oil trap and the sludge settled on the bottom layer are collected and sent into the stirring tank for further treatment.
The oil, water, and slag in the oily sludge treated can be separated continuously from each other through the high-efficiency three-phase used oil centrifuge.
The waste oil centrifuge can also used for drilling oil based mud. Its basic composition is oil, water, organic clay, and oil-soluble chemical treatment agent. OBM resists high temperature and calcium salt erosion, which is beneficial to the stability and lubrication of the well wall.
The mud has good lubrication and small damage to oil and gas layers, so it is widely used in drilling platforms. However, the slag generated in the equipment of drilling solid control system (vibrating screen, centrifuge, and dryer) has seriously affected the environmental safety and must be treated in a harmless manner. After treatment, the oil content of the slag is less than 1% and the oil is further purified and reused.
The collected drilling OBM wastewater is subjected to high-speed stirring in proportion, add a suitable amount of demulsifier, active agent, and other additives, makes the oily water in the emulsified state become liquid.
The vibrating screen is used before separation to remove large particles of soil, sand, glass bottles, mineral water bottles, convenient bags, gauze, and other solid wastes, and then the high-efficiency two-phase waste oil centrifuge is adopted to separate oil, water and slag continuously.
After heated by steam, the separated liquid phase enters the sedimentation tank, in which the supernatant is removed, and the liquid phase settled at the bottom mixed with the slag phase separated by the centrifuge. The residual oil is recovered by the thermal desorption process.