Kinetic Analysis of Methane–Propane Hydrate Formation by the Use of Different Impellers

Abstract

In the present study, the effect of different kinds of impellers with different baffles or no baffle was investigated. Up-pumping pitched blade turbine (PBTU) and Rushton turbine (RT) were the two types of impellers tested. The reactor was equipped with different designs of baffles: full, half and surface baffles, or no baffles. Single (PBTU or RT) and dual (PBTU/PBTU or RT/RT) use of impellers with full (FB), half (HB), surface (SB), and no baffle (NB) combinations formed two sets of 16 experiments. The first group of experiments was close to the equilibrium line (P = 26.5 bars and T = 8.5 °C), and the second group was deep in the equilibrium line (P = 24.5 bars and T = 2 °C). There was estimation of rate of hydrate formation, induction time, hydrate productivity, overall power consumption, split fraction, and separation factor. In both single and dual impellers, the results showed that RT experiments are better compared to PBTU in the rate of hydrate formation. The induction time is almost the same because we are deep in the equilibrium line while, hydrate productivity values are higher in PBTU compared to RT experiments. As a general view, RT experiments consume more energy compared to PBTU experiments.

Synthesis and Heavy-Metal Sorption Studies of N,N-Dimethylacrylamide-Based Hydrogels

“…Both pseudo-first- and pseudo-second-order kinetics models gave a closer value of adsorption ( Figure 7 and Figure 8 ). This shows that the pseudo-first and pseudo-second-order kinetics models both fit for adsorption kinetics [ 43 , 44 , 45 , 46 , 47 ]. However, Q e with a lower experimental value was found in pseudo-second order, and vice versa in pseudo-first order.…”

Explicating the amino acid effects for methane storage in hydrate form

“…24,25 These include mixing/agitating the sample using stirred reactor, rocking cells, and spraying the water into pressurized reactors using the high-pressure pumps. [26][27][28] Organic solvents and porous materials are also being studied to address these problems. [29][30][31] The search for novel material is still pursued to accelerate these processes for rapid kinetics and higher hydrate conversion.…”

Thermodynamics of hydrate systems using a uniform reference state

“…A number of interesting papers due to Longinos and Parlaktuna (Longinos & Parlaktuna [36][37][38][39] ) discuss interesting experiments on hydrate formation dynamics and effects of various types of chemicals that change hydrate formation dynamics. While these are very interesting papers, they stretch outside the main focus of this work.…”

“…In the absence of induced hydrodynamics, it has been demonstrated that slow mass transport through blocking hydrate films can predict experimental induction times (Kvamme et al 27 ). Another aspect related to the papers by Longinos and Parlaktuna [36][37][38][39] is the effect of selective adsorption of hydrate that forms on water surfaces, which, for instance, implies that adsorption of propane on liquid water surface will dominate compared with adsorption of methane (Kvamme 7 ). In summary, comparison with theories and experimental papers on hydrodynamic level requires a different theoretical approach than what is discussed here.…”

“…Efficient numerical algorithms make it possible to extend PFT 20,25,[40][41][42][43][44][45][46][47][48] to mm scale and can make it possible to incorporate many of the effects studied by Longinos and Parlaktuna. [36][37][38][39]…”