Research On Separate Production Theory And Design Method Of Lifting Parameters In Vertical Wells

Multiple-layered sandstone oil fields generally use commingled producing system.But,the difference of the reservoir pressure,petrophysical properties,and fluid properties will cause interlayer interference when layers are in the process of commingling production in multilayer reservoirs.The production of the total reservoir and each layer will be adversely affected.In this paper,the factors causing interlayer interference were analysed theoretically.On this basis,the influence of reservoir pressure,permeability and crude oil viscosity on the inter layer interference of multi-layer reservoirs were studied with numerical modelling software.The limit chart suitable for the separate-layer production was obtained.Seperate production pump is the new device which can exploit two oil layers at the same time,preventing the interlayer interference.Its working principle is different from conventional subsurface pumps.In this paper,according to the production characteristics,computational models of the stress on the sucker rod and the pump efficiency were established.On the above basis,the theoretical model of the lifting system of the seperate production pump was established.By using Visual Basic6.0,the software of "lifting parameter design of seperate production pump well" was developed.The software is able to configure lifting parameters for achieving the goal of maximum system efficiency or maximum liquid yield.By using an example,factors that affect the production,the pump efficiency and the system efficiency were analyzed.The models and the software were thus verified.