Abstract:
In order to reasonably evaluate the application effect of the staged fluid control completion technology, the theoretical evaluation method and comprehensive evaluation method were established based on the four production indices which included the cumulative oil production, the annual decline rate of daily oil production, the annual average water cut and increase range of water cut. Taking the Well D311P5 as an example, the production indices of the example well were calculated by numerical model to evaluate it theoretically under the conventional completion conditions. This allowed the researchers to establish the intermediary bridge for the comparison of the example well and two offset wells by staged fluid control completion under the conventional completion conditions. The method is suitable for those cases where there are few wells or there is a need to precisely evaluate the specific wells. The statistical evaluation method takes D311 fault block as an example. For each example well, two offset wells were selected, i.e. 12 example wells and 24 offset wells to form a comparison group. A total number of 96 comparison samples were established in Block D311 to analyze the production indices of the example wells and offset wells by virtue of field production data. The theoretical evaluation results indicated that under the conditions of conventional completion methods the production indices of Well D311P5 were basically the same as that of two offset wells. This result was consistent with the actual situation of three wells with similar production conditions. Well D311P5 obtained better production indices under the conditions of staged inflow control completion than that of conventional completion methods. Thus, the statistical evaluation results suggested that 70 comparison samples exhibited better production indices than that of the offset wells, accounting for 72.9%. The research results showed that staged fluid control completion technology had a good effect in Block D311, and achieved the purposes of oil increment, oil stabilization, water control and water production mitigation, which will provide good reference for evaluating its application effect in other blocks.