Field Test and Understanding of Fire Flooding in Shallow Ordinary Heavy Oil Reservoir of K Oilfield

K Oilfield is a shallow, unconsolidated sandstone conventional heavy oil reservoir. It has been developed using a patterned well network and two fire flooding methods, namely wet and dry, for nearly 15 years in the mining area. In order to summarize the characteristics of fire flooding development in K Oilfield, establish screening criteria suitable for fire flooding in K Oilfield, and evaluate the development effectiveness, this article conducts a fire flooding analysis based on production dynamic data and test materials, combined with a numerical simulation of the fire flooding mechanism model. The following understanding has been obtained: Fire flooding production wells in K Oilfield exhibit obvious effectiveness characteristics, and discerning criteria for the effectiveness of fire flooding have been established. Water production in dry fire flooding mainly comes from formation connate water. The water-free production period is long, and the water cut gradually increases after breakthrough. Water production in wet fire flooding comes from formation connate water and injected water. The water-free production period is short, and the water cut increases rapidly after breakthrough. Fire flooding is suitable for areas with oil formation thickness above 4m in K Oilfield, and a small well spacing of 100m is recommended for development. There are differences in the effectiveness between dry and wet fire flooding in K Oilfield. Dry fire flooding is affected by air override, resulting in poor mobilization in the lower part of the reservoir. Wet fire flooding, under the combined action of air override and water drive, has a greater vertical coverage compared to dry fire flooding and achieves better production results. The successful application of fire flooding in K Oilfield provides guidance for the development of fire flooding in shallow, conventional heavy oil reservoirs. Overall, the findings from the practice and understanding of fire flooding in K Oilfield contribute to the advancement of fire flooding techniques in shallow, conventional heavy oil reservoirs.