超临界多元热流体发生及地下原位转化开采重质油理论与技术

Heavy crude oil resources, including heavy oil and shale kerogen, have large reserves, but their exploitation is challenging due to their low mobility and low maturity. The commonly-used steam injection method exhibits low recovery rate, poor heat efficiency, and high cost. Therefore, it is critical to explore efficient, clean and low-cost methods for thermal fluid generation, reservoir heating, organic matter conversion and recovery to advance heavy crude oil development. To this end, a new technique for in-situ conversion and recovery of heavy crude oil using multi-component supercritical thermal fluid generation and injection. This method leverages the outstanding solubility, diffusivity, and reactivity of supercritical water. The process involves using organic waste in the oilfield to generate multi-component supercritical thermal fluid through supercritical water gasification and hydrogen oxidation. The fluid is then injected into the rcscrvoir, where it converts heavy crude oil and kerogen into light oil and gas, forming miscible flooding for enhanced oil recovery. Laboratory research shows promising results, with carbon conversion of organic waste, core flooding rate and four-round soak rate of heavy crude oil, and hydrocarbon generation rate from kerogen reaching 98%, 97%, 75%, and 60% respectively. These results suggest that heavy crude oil resources can be effectively exploited using supercritical water and multi-component supercritical thermal fluid, which offer high efficiency, low pollution and low cost. This innovative technique is of great significance for ensuring oil and gas energy security in China.