Abstract
In crude oil storage-dispensing terminals often problems are encountered regarding dispensing and processing of crude oil at near dead volume capacity of the tanks. Similar problems are encountered while cleanout procedure of tanks for maintenance and repair. In our first consideration processing of crude for treating or dehydration is brought to picture. For crude processing or tank to tank transfer problem arises below dead volume with high flow high pressure circulation pumps. The problems observed are low suction pressure, reduced flow and pressure at discharge end, frequent gas formation at suction, high flow induced vibration at pump suction and frequent failure of dynamic seals. Most pumps used in this scenario are centrifugal pumps (following API 610 codes and API 682 for mechanical seals). For our purpose single stage centrifugal pump is considered. The pump deigns and dead volume level calculation attributes to the problems encountered. Moreover, during the clean-out procedure it becomes difficult for most pumps even with low NPSHR to efficiently pump out the liquid below dead volume level. This creates severe volume build-up and even causes damage to pumps at very low level partial dry run condition. Our aim is to conceptualize and furthermore develop a compact vacuum-pump system which can be used for continuous delivery of fluid even beyond specified dead-volume level. The equipment would have the capability to work on very low-level fluid storage. Again, in traditional vacuum and pump system there is a drawback of swing operation of vacuum and pump system which greatly affects the operation time of any process. This literature will help in identifying the core problem of swing operation and inline draw a concept of the new pump-vacuum system which eliminates need for a swing operation i.e., simultaneous operation of evacuation and pumping can be carried-out. Also, it is aimed to explore further applications of the system for booster application. Vacuum systems consist of vacuum pumps and tanks mounted on a skid or truck. The vacuum pump creates a vacuum in the tank and the oil moves directly through a hose or pipe to the tank from the skimmer or the source of the oil. The oil does not go through the pump, but moves directly from its source into the tank. Vacuum systems can handle debris, viscous oils, and the intake of air or water. The vacuum tank requires emptying, however, which is usually done by opening the entire end of the tank and letting the material move out by gravity [1].
