01845nas a2200229   4500008004100000022001400041245011200055210006900167260007700236300001200313490000600325520102600331653001501357653001301372653001501385653001301400653002401413100001901437700001901456700001901475856012101494       2015                        eng d  a2194-428800aInfluence of low-dosage hydrate inhibitors on methane clathrate hydrate formation and dissociation kinetics0 aInfluence of lowdosage hydrate inhibitors on methane clathrate h  aBOSCHSTRASSE 12, D-69469 WEINHEIM, GERMANYbWILEY-V C H VERLAG GMBHcJUL  a717-7250 v33 a<p>This work investigates the effect of low-dosage hydrate inhibitors (LDHIs) on methane hydrate formation and dissociation. The hydrate inhibitors used in this study were the sodium salt of polyacrylic acid, a polysaccharide chitosan, and the linear sulfated polysaccharide i-carrageenan; the inhibiting behavior of these additives were compared with that of the commonly used hydrate inhibitor polyvinylpyrrolidone for methane hydrate formation. A LDHI concentration of 1wt% was found to increase the induction time relative to that at a LDHI concentration of 0.1wt%. Chitosan was found to be better than the others in reducing nucleation and the growth rate of the hydrate at a concentration of 1wt%. At a lower concentration of 0.1wt%, nucleation inhibition was minimal, however, growth inhibition was significant. The effect of these inhibitors on the decomposition rate of the hydrate was also studied, and the decomposition kinetics at a constant driving force in excess of three-phase equilibrium is reported.</p>10agas uptake10ahydrates10ainhibitors10akinetics10athermal stimulation1 aKumar, Asheesh1 aSakpal, Tushar1 aKumar, Rajnish  uhttps://library.ncl.res.in/content/influence-low-dosage-hydrate-inhibitors-methane-clathrate-hydrate-formation-and-002556nas a2200289   4500008004100000022001400041245007500055210006900130300001600199490000800215520170000223653002101923653001701944653001701961653001301978653000901991653002002000653002302020653002402043100002602067700002002093700002202113700002102135700002002156700001902176856007102195       2019                        eng d  a1876-610200aMethane hydrate dissociation in the presence of novel benign additives0 aMethane hydrate dissociation in the presence of novel benign add  a5856 - 58650 v1583 a<p>The apparent drawbacks of the classical approaches towards dissociation of natural gas hydrates have resulted in a paradigm shift into the development of new hybrid hydrate dissociation practices combining the various basic hydrate dissociation techniques. Another approach that can be followed to maximize the efficiency of gas production from natural gas hydrate reserves is the identification of benign additives which when used even in sparingly small concentrations may enhance the kinetics of hydrate dissociation. In the present work, a class of such additives, never reported before, have been unveiled and christened as Low Dosage Hydrate Dissociation Promoters (LHDPs). The additives were first short listed from a wide potential pool using a lab scale ( 250 ml) stirred tank reactor setup and then further studied using a bench scale ( 2.35 l) reactor setup where they were injected in the form of a water-additive stream to dissociate hydrates. The dissociation approach followed in the case of the bench scale reactor experiments was a combination of the thermal stimulation and depressurization processes along with the element of injection of additives. For both sets of experiments (lab and bench scale), the newly identified LHDPs were found to enhance the kinetics of methane hydrate dissociation as compared to pure water. It was observed that concentration of additive and its flow rate also affect the kinetics of methane hydrate dissociation. An energy and efficiency analysis for the hydrate dissociation method in the case of bench scale rector revealed that additive presence enhanced the energy ratio and thermal efficiency four fold as compared to pure water.</p>
10aDepressurization10aDissociation10aEnergy Ratio10akinetics10aLHDP10amethane hydrate10aThermal Efficiency10athermal stimulation1 aBhattacharjee, Gaurav1 aBarmecha, Vivek1 aChoudhary, Nilesh1 aPande, Nawal, K.1 aChugh, Parivesh1 aKumar, Rajnish  uhttp://www.sciencedirect.com/science/article/pii/S1876610219305648