Research On The Influence Of Pressure Disturbance On The Synthesis Of Methane Hydrate

As an important energy source in the 21st century,natural gas hydrate has entered the trial mining stage in the world,and industrialized mining is imperative.However,application technologies based on natural gas hydrates have yet to be improved,such as energy gas storage and transportation,and carbon dioxide storage.There are many ways to promote the synthesis of natural gas hydrates,but each method has its own drawbacks.The main problems are slow synthesis speed,low gas storage density,and inability to industrialize applications.This paper aims to explore the rapid synthesis of methane hydrate by pressure disturbance.Since methane hydrate synthesis has certain randomness,this paper firstly carried out the experiments of methane hydrate synthesis under static conditions which have different temperature and pressure.Secondly,the experiments of the effects of supercharging on the synthesis of methane hydrate during the synthesis of methane hydrate was carried out.The mechanism of the energy change during the pressurization and the mechanism of methane hydrate synthesis were analyzed.Then,this paper first proposed the use of antihypertensive method to promote the synthesis of methane hydrate in the synthesis of methane hydrate,and carried out experiments with different temperatures,different initial pressures,different depressurization amounts,and different depressurization moments.By calculating Gibbs free energy,the pressure disturbance is negated by increasing energy to promote methane hydrate synthesis.The synthesis mechanism of the pressure reduction promoting methane hydrate was analyzed.Finally,the calculation method of gas storage density was improved,and the differences in appearance,induction period,synthesis rate and gas storage density of methane hydrate between static synthesis and depressurization experiments and pressurization experiments were compared.Through research,it is found that:(1)static synthesis of methane hydrate has great randomness.The average induction period of the experiment in 7MPa and 2? is 44122S,and the average induction period in the 7MPa and 4? experiments is 48742S.The average induction period of the 5.5 MPa and 2? groups was 52880S.During the induction period,as the pressure increases,the temperature decreases.(2)Pressurization under different experimental temperature and pressure conditions can promote the synthesis of methane hydrate.The amount of pressure disturbance has no significant effect on promoting methane hydrate synthesis.The synthesis success rate was 70%in the experiment of pressurization time point is 1800S,and the 3600S experimental success rate was 100%.(3)The reduction of pressure in different experimental temperatures and pressure conditions can promote the synthesis of methane hydrate,and has a promoting effect under different depressurization amounts.The probability of successful synthesis of methane hydrate in the repeated experiments at 1800S and 3600S of the depressurization time point was 90%.(4)Compared with static synthesis,the depressurization method can effectively shorten the rapid synthesis period,which is about 67%of the static synthesis,but the gas storage density is lower;the rapid synthesis period of the pressurization method is about 120%of the static synthesis,but Its gas storage density is high,reaching 89%of the theoretical value.