Study On The Mechanism Of Oil Shale In-situ Conversion Production By Heating

With the deepening of unconventional shale oil and gas development,oil shale in-situ conversion production by heating has received more and more attention,and the mechanism of oil shale in-situ conversion production by heating needs to be further studied.On the basis of studying many documents,the previous research results were summarized and the mechanism of oil shale in-situ conversion production by heating was further studied in depth.In-depth analyses of the heating characteristics of electric heating and thermal fluid heating and the influence of reservoir parameters on heating effect,the heating characteristics of electric heating well pattern and thermal fluid heating well pattern and the influence of well pattern parameters on heating effect,the oil and gas production characteristics of electric heating vertical well production well pattern and thermal fluid heating horizontal well production well pattern and the influence of production parameters on oil and gas production were given.This is of great significance for revealing the reservoir characteristics and oil and gas production rules during the in-situ production of oil shale so as to develop oil shale resources reasonably and efficiently.Firstly,based on the experimental results of oil shale pyrolysis,the previous kerogen pyrolysis reaction model was modified and the model parameters were fitted to establish a kerogen pyrolysis reaction model.Based on this,the variation laws of kerogen pyrolysis products,oil and gas saturation of oil shale,and pore pressure of oil shale with time were studied,which shows that the established model can well reflect the characteristics that crude oil lightens and pore pressure increases during heating extraction.Secondly,based on literature research,the variation laws of porosity,permeability,heat capacity,and thermal conductivity during in-situ conversion of oil shale were summarized.The heating characteristics of two heating methods and the influence of reservoir parameters on heating effect,as well as the heating characteristics of two heating well patterns and the influence of well pattern parameters on heating effect were studied.Then,the reasonable well pattern parameters for two oil shale heating well patterns were determined.Finally,based on the geological parameters of the pilot area,three production well patterns in the pilot area were established,and the production characteristics and the influence of production parameters on oil and gas production were analyzed.According to the cumulative tons of oil equivalent and energy output-input ratio,it was determined that the thermal fluid heating horizontal well pattern is the most suitable for the pilot area.