METHOD AND PROCESS FOR EXTRACTING SHALE OIL AND GAS BY FRACTURING AND CHEMICAL RETORTING IN OIL SHALE IN-SITU HORIZONTAL WELL

摘要

A method and a process for extracting shale oil and gas by fracturing and chemical retorting in oil shale in-situ horizontal well. An inclined well is drilled from the ground to the upper part of an underground oil shale stratum, and a horizontal well is drilled in parallel to the oil shale stratum in the upper part of the oil shale stratum. Behind the horizontal well and the inclined well in the upper part, an inclined well leading to the lower part of the oil shale stratum is drilled, and a horizontal well is drilled in parallel to the lower part of the oil shale stratum. Highly pressurized media (air, water, and quartz sand) are injected into the horizontal well in the upper part of the oil shale stratum, cracks of 1 to 3 mm are fractured in the oil shale stratum with the horizontal well in the upper part of the oil shale stratum serving as the center and are filled with a gap support, and, an oil and gas channel connecting the horizontal well in the lower part is established. A heating apparatus is added into the horizontal well in the upper part of the oil shale stratum, the oil shale stratum is heated to 550 DEG C., the oil shale is initially retorted, shale oil and gas are extracted, and the shale oil and gas are led out of the ground from the horizontal well in the lower part via the oil and gas passages, and then are introduced to an oxidant for oxidization reaction with asphaltenes and fixed carbon contained in the oil shale when retorted, where the heat generated is used as a heat source for subsequent retorting, thus implementing underground in situ shale oil extraction. The shale oil that is led out of the ground is separated via a ground-level gas-liquid separation apparatus, and the separated shale oil is transferred to a product oil tank for storage and sale, while a combustible gas is transferred to a combustible gas power generation apparatus for use in power generation. This solves the problem that existing ground-level retorting has in terms of large recovery costs, difficult treatment of tailings, a variety of environmental issues, and large land-use footprint. In addition, there disclose a process implementing the method and a nozzle used in the method.