Optimizing The Development of Water Drived Naturally Fractured Gas Reservoir

• Main Author: SURYA FAJAR (NIM : 22208041), DENDY
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/21637
• Institution: Institut Teknologi Bandung

The Harmony Field is a naturally fractured reservoirs that produced gas. The reservoirs on this field lies in its 4 formation, which is Formation A, B, C, and the Basement that consist of lithology such as limestone, dolomite, conglomerate and meta-sedimen rocks. Fracture on reservoir rocks are very important in rocks permeability. The Harmony Gas Field has already produced since 1998 with recovery up to 53 % until now. Till now the 3 wellhas been used for production. The akifer <br /> <br /> <br /> have a strong influenced on gas production, the water infkus will effecting reservoir pressure, water rate, and at the end the gas production. The field development are done to maximized the gas production by adjusting gas rate without adding more wells number. 4 skenario are made with recovery increment up to 3% from the base case. The field developments skenario are made with respect to water production control and pressure maintennance. Skenario I, were made with keeping up the primary constraint which is gas rate with 20 MMscf/d for each well, and maximum water rate up to 2000 bbl/d. The forecast that were done by reservoir simulation are resulting 2.315 X 105 MMscf/d cummulative gas production and 73.7% recovery. This skenario will be used as base case for the evaluation with others skenario. Skenario II, were made with maximizing production in one well that are already producing alot of water, and activate the other well that produced lower water rate to maintain the gas production rate plateu, as the decreasing production of the 1st well. The forecast that were done by reservoir simulation are resulting <br /> <br /> <br /> 2.38 X 105 MMscf/d cummulative gas production and 75.76% recovery. Skenario III, were made with cyclic system, so the water contact and pressure arround well are controled and preserved while clossing the well. The forecast that were done by reservoir simulation are resulting 2.361 X 105 MMscf/d cummulative gas production and 75.18 % recovery. Skenario IV, were made by producing the 2 wells together with 20 MMscf/d gas rate constraint and as the water rate increase, lowering the gas rate to 10 MMscf/d accprding to each well potention. The forecast that were done by reservoir simulation are resulting 2.409 X 105 MMscf/d cummulative gas <br /> <br /> <br /> production and 76,69 % recovery. The conclussion for these study, besides the result of each skenarios, are <br /> <br /> <br /> on the history matching process two factor that having a great effect are aquifer and fracture transmisibilities. The best skenario are skenario IV, who produced Onyx-A6 and Onyx-A1 well together with gas rate 20 MMscf/d each, and then individually decreasses to 10 MMscf/d with respect to water production, these skenario also have the lowest uncertainty.