Research On Well-balanced Steam Injection ICD Completion Technology For Horizontal Wells In Heavy Oil Reservoirs

The thermal recovery technology is the prime method in developing heavy oil reservoir. The horizontal well technology has been widely used in oil field and now it is applied to thermal recovery. The production in horizontal well is higher than vertical in heavy oil reservoir, but the steam profile is not in balance due to the structure of the horizontal well, which results to the low sweep efficiency of steam, the production is influenced at the same time.In order to solve this problem, many researches on steam injection and well completion have been done around the world. The efficient steam profile control measures in abroad include limited entry perforation (LTP), dual-string steam injection and inflow control device (ICD). The mostly efficient domestic methods involve separate layer steam injection technology, automatic steam distribution process and so on. The profile can be balanced to some extent, but as those process are complicated, which makes it difficult to spread. The ICD well completion is relatively efficient and simple within all those steam profile control methods, since the study about the ICD application in horizontal well in bitumen recovery is insufficient in domestic, it is necessary to do some researches about ICD well completion.Firstly, the ICD well completion technology is studied. A model was built for calculating ICD parameters. The model took the influences of the ICD to the steam flowing into consideration, could be used to calculate the steam pressure, temperature, quality, heating radius, oil-steam ratio, the number and diameter of ICD nozzle. The calculation result of a steam huff-and-puff well in X oilfield in western China showed that the steam distribution is balanced after completed by ICD. The average oil-steam ratio is raised by 17% after 5 circles, the efficiency of steam injection and production are improved.Secondly, the paper studied the ICD well completion in SAGD wells. Built a single-string steam injection ICD well completion model in SAGD wells. The effect to the steam chamber by ICD can be quantificated in this model. The model could be used to calculate the steam parameters in both tube and screen, also did the steam-oil ratio and ICD parameters. The comparison between conventional screen and ICD well completion in SAGD wells in X oilfield indicated that the ICD technology cut down the instantaneous steam-oil ratio by 25%, prevented the steam from breakthrough in toe area and improved the bitumen production.Finally, compiled a software for designing and calculating ICD well completion in heavy oil horizontal well based on Microsoft Visual Studio 2013 and the model built before.The conclusion is that the ICD well completion can solve the unbalanced steam profile problem in heavy oil horizontal well, the models can be used to design and calculate the ICD well completion, the design method formed in this paper can be a guide to domestic heavy oil recovery.