Method for mining thin inter bed oil shale

Abstract

The invention relates to a method for mining thin inter bed oil shale. The method comprises the steps that first, a first well completion shaft and a second well completion shaft are arranged downwards from the ground surface of the distribution area of the oil shale, and the first well completion shaft and the second well completion shaft both penetrate through a same oil shale layer; second, an artificial fracturing method is adopted, a crack communicating the first well completion shaft and the second well completion shaft is formed in the oil shale layer; and third, water vapor is injected into the first well completion shaft, and oil gas is collected from the second well completion shaft. The water vapor is injected into the first well completion shaft, and enters the crack. The water vapor brings heat into the oil shale layer. When the oil shale layer is heated, and the temperature of the oil shale layer reaches the pyrolysis temperature of kerogen, the kerogen in the oil shale layer is pyrolyzed. The oil gas enters the second well completion shaft and is mined from the second well completion shaft. The heat content of the water vapor is large, stratums are quickly heated when being heated by the water vapor, and the method is environmentally friendlier.

Description

technical field [0001] The invention relates to an oil and gas exploitation technology, in particular to a method for exploiting thin interlayer oil shale. Background technique [0002] Oil shale refers to very fine-grained sedimentary rocks containing large amounts of immature organic matter or kerogen. The immature kerogen can be converted into liquid hydrocarbons by pyrolysis of oil shale at high temperature (350-500°C). my country's oil shale resources are very rich. According to the results of a new round of oil and gas resource evaluation commissioned by Jilin University in 2005 by the Ministry of Land and Resources, my country's oil shale resources converted into shale oil resources are 47.644 billion tons, and shale oil can be recycled. It is 11.979 billion tons, second only to the United States and ranks second in the world. It is mainly distributed in Nongan, Huadian and Luozigou of Wangqing in Jilin, Fushun in Liaoning, Maoming in Guangdong, Longkou in Shandong an...

AI Technical Summary

Problems solved by technology

The core of fluid heating technology is to form effective thermal communication, but whether it is Chevron’s petrochemical technology or the so-called mechanical fracturing method of American shale oil companies, for oil shale reservoirs with thin layers and many interlayers It is difficult to form enough fractures, and it is difficult to inject ordinary water vapor to reach the temperature required for kerogen pyrolysis

[0007] A typical representative of radiation heating technology is the radio frequency microwave heating RF / CF technology proposed by American Raytheon Company, which uses radio frequency and injects supercritical carbon dioxide to heat oil shale reservoirs to the cracking temperature, but because oil shale itself is a kind of microwave weak absorption Medium, also has the disadvantages of slow heating rate and low heating efficiency

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