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From decades ago till now, most oil wells in Iran produce using their natural flow potential and they don't need to be fractured. This is why few cases of hydraulic fracturing are recorded in the history of Iranian oil industry. This paper reviews the three cases of acid fracturing previously conducted in an Iranian oil field based on the available data. In addition, a mere propped fracturing was also designed to be carried out but due to some problems the whole operation was cancelled. As time goes by, the reservoir pressure depletes and the need for hydraulic fracturing as stimulation practice arises. Studying the previous fracturing jobs is beneficial when designing a new treatment, thus lessons can be learnt from them.The status of the candidate selection of these wells is discussed firstly in this paper. It is important to choose appropriate wells for such an expensive stimulation practice as hydraulic fracturing. Through modeling the wells the effects of fracturing on the production performance, i.e. production rate, of these wells are considered. A successful hydraulic fracturing should improve the productivity of the well. The available build-up tests are also investigated to diagnose any induced fracture in the formation. Fracturing the formation changes the flow regime around the wellbore and this change can be distinguished through analyzing pressure transient testing data.

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The difficulty of maintaining the wellbore pressure should be overcome by precisely predicting the wellbore pressure. The empirical models used widely by UBD simulators give a large error and may not be extendable to other UBD cases. For this reason, Mechanistic modeling has been applied to two phase flow with a number of assumed values for the existent coefficients varying from one UBD case to another. Therefore, in this paper, a new comprehensive mechanistic model is developed mathematically for Iranian Oil fields to match the characteristics of the corresponding UBD jobs in Iran by modifying the constant values of Lage et al, Perez Telez at al., Mousavi et al. and Ansari et al. mechanist models. It is compared with Ansari et al, the specifically developed mechanistic model for use in South of Iran.Since the mechanistic models use mathematical relations with assumptions for the values of the constants rather than pure empirical study of two phase flow, the mechanistic models developed and validated with data outside Iran are not good enough to be used. In this paper different constant values have been tested and the ones which have led to the least average absolute error have been picked up to present a specific mechanistic model for South of Iran.The empirical models which have been developed outside Iran cause erroneous results. The results illustrate that the new mechanistic model predicts BHCP with an error much less than Ansari et al. Mechanistic Model.

In some Iranian oil fields hydrocarbon recovery is mainly from sandstone reservoirs and sand production is a major problem in these fields. Main reason of sand production in these reservoirs is due to unconsolidated sandstone layers. The common method to decrease this problem is achieved by installing mechanical sand control systems. Previously, some techniques of sand control have been used in Iranian oil fields, such as gravel packing, slotted liner and chemical consolidation by resin. The results which have been obtained through these methods are not remarkably good enough in some cases. Expandable sand screen (ESS) is a new technique in sand control that can result in lower skin and consequently improves reservoir inflow performance. Field tests in various conditions have shown very satisfactory results in both open and cased hole applications. This paper will provide a brief overview of ESS and its advantages and will explains some of the concerns deal with ESS well completion. It provides details of well production results before and after installation of ESS. It also suggests that the use of ESS as an alternative to conventional sand control methods in Iran oil fields is preferable specially in cased hole completed wells.