Method for extracting shale oil gas by oil shale in-situ topochemical method

Abstract

The invention discloses a method for extracting shale oil gas by an oil shale in-situ topochemical method. The method includes: a partial chemical reaction area is formed in an underground oil shale stratum via hot mixed gas; in the whole process, a series of 'chain reactions' are induced by means of controlling concentrations of injected hot mixed gas and recovered hot mixed gas, and along with gradual temperature rising and range widening of the reaction area, porosity and permeability of the oil shale stratum increase continuously, heat strengthening reaction processing is realized finally, and self catalytic cracking of the oil shale stratum from inner to outer is achieved to generate shale oil and fuel gas. After the chain reactions are over, fixed carbon in the oil shale stratum is continuously enabled to react to generate low-heating-value gas via the hot mixed gas, high-temperature waste heat in the area finished in cracking reaction is recycled, and self-supporting and maximal utilization of energy for the oil shale stratum cracking are realized. By the aid of the method, exploring method, environmental harms and commercial risks can be reduced.

Description

technical field [0001] The invention relates to an oil shale mining technology, in particular to a method for extracting shale oil and gas by in-situ local chemical reaction of oil shale. Chemical reaction is used to crack the organic matter in oil shale to extract shale oil and fuel gas, and high waste heat is recycled to the area where the cracking reaction is completed. It is a method that can realize energy self-sufficiency and heat utilization rate maximization of in-situ cracking of oil shale. This technical method can be widely used in in-situ mining of solid or condensed mineral fuels (oil shale, coal, heavy oil). Background technique [0002] Over the past two decades, the global demand for energy has grown rapidly, and oil prices have repeatedly hit new highs. In 2012, the global consumption of crude oil reached 89.05 million barrels per day. The U.S. Energy Administration predicts that by 2030, the world’s crude oil production will reach its peak and then declin...

AI Technical Summary

Problems solved by technology

However, there are many disadvantages in the production of shale oil by surface dry distillation: heavy excavation workload and high cost; easy to form gobs, leading to land subsidence; difficult to deal with a large amount of residue, large accumulation, easy to cause secondary pollution; discharge a large amount of waste gas and Sewage pollutes the environment heavily; water consumption is large, etc.

Although this kind of complete underground combustion can provide a large amount of heat for the cracking of kerogen in oil shale, it is a non-recoverable mining method, and the reaction process is not easy to control. If it is not properly controlled, a large amount of oil may be consumed Shale or kerogen, which reduces the extraction rate of oil shale. In addition, in a wet and relatively closed underground environment, there are high requirements for ignition devices and media.

[0007] The above-mentioned underground in-situ mining oil shale methods all have the disadvantages of high cost, low efficiency, and large heat loss.

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