Wenchang oilfields in the development process, with the increase in development time, the amount of fluid to continuously improve mining, underground rock formations gradually loosened. Various siltstone formation sand enter the production system with crude oil. This will not only cause damage to the wellhead platform devices such as filters, external pump, pipelines and other devices, and greatly reduces the oil quality, has a direct impact on economic.Wenchang oilfields generally use electric submersible pumps driven mining.
With the gradual development of oil into the late, production rate is rising, resulting in a formation pressure decline, reducing the strength of the rock, rock and other unconsolidated. Siltstone, sand formations will be promoted to the production system with oil. Sand in the platform produced fluid processing system caused great harm. The main performance is as follows.1. The presence of fine sand would corrode piping, pumps, valves, stop valves and other surface gathering equipments. 2. Oil wrapped sands form impact on the production of water treatment systems. 3. Sand or mud, hard calcium scale, as well as compaction of both common and grease, will have very serious impact to the following process. 4. Accumulation of sand will affect the separator separation effect, and harm to the normal operation of sea pipe. 5. The cumulative of sand impact the normal operation of crude oil transfer pump, you need to be constantly switching row of sand, otherwise it will affect productivity or even block mechanical seal.
For these growing conditions appeared in oilfields, application of appropriate characteristics of grit removal equipments for platform is particularly urgent. Based on the factors of platform’s production technology, working conditions, and space conditions, on the basics of analysis and comparison of domestic offshore oil production and other fields the technical characteristics of the solid-liquid two-phase separation, such as Large sedimentation tanks, plate separation, static cyclone separation method and some other mathods. Integrate various technical advantages, design and manufacture high efficiency cyclone desander with desanding function. This application tests conducted in Wenchang oilfields platform and achieved a great success.
Dynamic cyclone desander is based on a static cyclone desander, combined with independent patent separation angle and high precision mechanical seals developed an efficient, stable, advanced equipment. Its principle is that the oil enter into desander rom the entrance, generated large angular velocity and tangential acceleration by the rotation of the impeller. At the same angular velocity, the solid and liquid phases generated different centrifugal force due to the density difference. High density solid particles were thrown the inner wall of the cyclone, small density liquid was left near the center of the cyclone. While solid particles were thrown to the inner wall of the cyclone, they along the downward movement of the spiral housing wall. Finally discharged from the bottom orifice and deposit the sand tank, and it need regularly cleaning. In the center of the cyclone, due to the liquid high speed rotation, generated a low-pressure spiraling flow, liquid discharged from the overflow pipe with this spiraling flow. So as to achieve the effect of separating grit removal.