Experimental Study of Hydrate Formation in Non Emulsifying Oil Systems in Shut-in and Restart Conditions

Defining a Slurry Phase Map for Gas Hydrate Management in Multiphase Flow Systems

“…One should now recognize that, although the criterion of eq is rather simple, all of the above-mentioned trends are in agreement with simulation trends reported in our previous studies that use much more detailed physics and much more sophisticated mathematics. ,, Section 2 of the Supporting Information brings the comparison of the slurry phase map against Kakitani’s data set using a rock-flow cell apparatus and shows a remarkable agreement considering that no direct fittings are done and that there is still room for a vast improvement in the experiments.…”

“…Still in oil-continuous scenarios, all free water is reported to rapidly get entrapped inside the porous structure of the particles during the onset and initial growth period of hydrate formation , because of the hydrophilic nature of gas hydrates . This means that the initial concentration of particles can be considered the same as the water cut.…”

“…This rearrangement is caused by the perturbation of the interfacial energy once the first hydrate seeds nucleate in the oil–water interface, leading to a quick coalescence of water droplets while their water content is getting entrapped in the porous particles. Experimental evidence however points out that the initial particle size still remains in the same order of magnitude of the water droplets, ,, in the 10–1000 s micrometer scale, and therefore droplet size models can be used as an estimate of the initial particle size. This is expected to hold for low water cuts and high flow rates, where the water droplets do not interact during the onset of formationtypical values of low water cut are up to 10–20%, but the actual values depend on the fluid properties and flow conditions (i.e., flow regime).…”

“…It was shown however that water can be prevented from permeating through the particles and spreading over the outer surface. , Because crystallization happens mainly in the capillary walls, the particle porosity decreases in time, sealing the water content inside of the particlesee detail (i) of Figure c. These are called dry particles , and they are inert in the sense of agglomeration because they cannot form any liquid bridge upon collision.…”