| 主权项 |
1. A computer-implemented method for determining one or more operating modes for a crude oil displacement system, the crude oil displacement system being arranged to inject an injection water into a reservoir, the reservoir comprising at least two carbonate rock layers having crude oil present within a pore space thereof, said crude oil displacement system being for use in displacing crude oil from the pore space of the carbonate rock layers,
the method comprising the steps of: receiving input data indicative of:
i) characteristics of the injection water, comprising temperature, salinity, and sulfate concentration; andii) characteristics of the carbonate rock layers comprising temperature, permeabilities of the carbonate rock layers, water-soluble sulfate mineral content of the carbonate rock layers, and an indication of permeabilities of one or more interfaces between adjacent ones of the carbonate rock layers; inputting said input data into a computer-implemented predictive model; operating the predictive model so as to:
a) identify one or more first carbonate rock layers and one or more second carbonate rock layers of the at least two carbonate rock layers, the one or more second carbonate rock layers being adjacent to at least one of the one or more first carbonate rock layers, the one or more first carbonate rock layers having a relatively high water-soluble sulfate mineral content and the one or more second carbonate rock layers having a relatively low water-soluble sulfate mineral content;b) model, using at least the data indicative of the characteristics of the injection water and of the characteristics of the carbonate rock layers, dissolution of water-soluble sulfate minerals from at least one first carbonate rock layer of the one or more first carbonate rock layers into the injection water that will occur on configuring the crude oil displacement system to inject said injection water into the at least one first carbonate rock layer, whereby to generate first data representing chemical characteristics of a sulfate enriched aqueous displacement fluid formed in the at least one first carbonate rock layer by the dissolution of water-soluble sulfate minerals into the injection water;c) model, using at least the data indicative of the water permeabilities of the carbonate rock layers, flow of the sulfate enriched aqueous displacement fluid through the at least one first carbonate rock layer, whereby to generate first flow characteristics of the sulfate enriched aqueous displacement fluid;d) model, using at least the data indicative of the water permeabilities of the carbonate rock layers, the water permeabilities of the one or more interfaces and the first flow characteristics, flow of the sulfate enriched aqueous displacement fluid from the at least one first carbonate rock layer into and through at least one second carbonate rock layer of the one or more second carbonate rock layers, whereby to generate second flow characteristics of the sulfate enriched aqueous displacement fluid; ande) generate, based on at least the first data and the modelled second flow characteristics, second data indicative of a predicted amount of oil that will be displaced from the at least one second carbonate rock layer by the sulfate enriched aqueous displacement fluid formed in the at least one first carbonate rock layer responsive to configuring the crude oil displacement system so as to inject the injection water into the at least one first carbonate rock layer; and determining, on the basis of the second data, control data indicative of one or more operating modes of the crude oil displacement system. |
