Experimental Evaluation Of Natural Gas Hydrate Well Completion System

Natural gas hydrate is a clean energy source,which has attracted the attention of researchers around the world because of its high calorific value.At present,four countries,including Japan and China,have carried out experimental mining of natural gas hydrates,and have achieved results to a certain degree.They have also discovered various problems in the mining process,such as sanding.Therefore,further research is needed to explore and improve knowledge of drilling and completion,mining and other aspects.In this paper,the control variables experiments were carried out on different completion methods such as vertical well perforation completion,straight well cut completion and horizontal well perforation completion,and the effects of different completion methods on the decomposition of natural gas hydrate were studied.Collecting,analyzing,and studying the decomposition process of natural gas hydrates,and fitting the data of the decomposition process;comparing the overall yield,overall pressure,medium-term production,medium-term pressure,temperature,and production in the decomposition process by comparing and analyzing the fitted data.Parameters such as gas velocity are studied.The experimental results show that the production pressure difference,contact area and well type are the main factors affecting the decomposition of natural gas hydrate.The production pressure difference affects the decomposition rate.The smaller the production pressure difference is,the smaller the gas saturation is,the larger the fugacity difference is,the faster the reaction rate is.Similarly,the contact area affects the gas production rate,and the contact area is larger,the decomposition of natural gas hydrate The faster the rate;the different completion methods affect the decomposition rate of natural gas hydrates.The gas production rate of horizontal well perforation completion is greater than that of straight wells,which is greater than vertical well perforation completion.Based on geological and engineering conditions,on the basis of evaluation of completion methods,the completion method is preferred to achieve optimal exploitation of natural gas hydrates.