Overseas X Oilfield Reinjection Utilization Of Associated Gas

Natural gas is a kind of ideal energy and qualified chemical material, the associated gas is dissolved in the oil, it is a kind of available energy which storage deep in the formation with the crude oil. and will escape during the exploitation of oil. Its component includes methane, ethane, propane, butane and pentane, nitrogen and hydrocarbon, etc.Because of the restrict of technical measures, the recovery of associated gas is complex. At present most of oil fields often direct exhaust or ignite the associated gas, thus this part of energy has not been able to recycle and utilize effectively.But the environmental pollution of exhaust and burning is very serious, and also causes considerable energy waste. With greater efforts made to cure air pollution around the world, the recycle of associated gas is very important.In this paper, associated gas flaring is forbidden according to the policy of the reservoir area, at the same time,the government adopts a variety of preferential policies to encourage the development and utilization of natural gas. Because there have no underground pipeline for storage and transportation, in order to reduce the waste of resources, and let the associated gas to be better used, the study of re-injecting associated gas into reservoir is of great significance.The paper completed the following main contents:(1)Establish the3D geological model of C3gas reservoir based on the geological data, the geological data needed for geo-modeling includes:structural characteristics of the gas reservoir, single well logging interpretation, geologic layering results, and contour map of reservoir properties (porosity and permeability)calculate the reserves,.The geological model is close to the real situation..(2)Combined the PVT test data with geological model, the paper establish the numerical simulation model of C3gas reservoir.(3) Use the compositional numerical simulation technology to predict wellhead pressure of injection well and pressure at different gas injecting rate, predict the formation fracture pressure.(4)Analyze the feasibility of associated gas re-injection and the sensitivity of tubing size and injection rate on the wellhead pressure of injection well.(5)Predict the largest volume of C3gas reservoir can be accommodated.