Experimental Study On Hydrate Decomposition And Secondary Formation In Mortar System

With the discovery of undersea natural gas resources and in-depth researches on hydrate,solid fluidization as a revolutionary technology has been widely concerned by scholars around the world.However,the formation and decomposition rule of hydrates in the mortar system formed by solid fluidization mining is not clear.This paper proposes the research topic of "experimental study on hydrate decomposition and secondary formation in the mortar system",aiming at the hydrate decomposition and secondary formation in the mortar system formed by solid fluidization mining.The results show that: gravel particles can inhibit hydrate induction but promote the growth rate of hydrate;under the influence of memory effect,the system is easier to form hydrate and the production time will increase;the gravel-bearing system has a greater risk of secondary formation of hydrate;gravel can counteract the inhibitory effect of salt and promote the growth of hydrate;salt will affect or even destroy the memory effect,the higher the salt concentration,the more obvious the inhibition of hydrate formation,but the salt can accelerate the decomposition rate of hydrate;the influence law of gravel-salt ratio on hydrate is not obvious;there is little difference in the law of methane hydrate decomposition in each system,so it is still necessary to carry out experimental researches on hydrate decomposition in different ways in the future;the second formation model of hydrate and the hydrate decomposition model are established in this paper,and the calculated value is in good agreement with the experimental value,which can provide some references for the actual working condition.