Effect of Produced Sand Particles and Fines on Scale Inhibitor: A Review

Application of scale inhibitors in oil and gas production is aimed at mitigating scale blockage during production. Many experimental, mathematical, and numerical simulation modeling works have been carried out to evaluate behavior, performance, and interaction of the scale inhibitor chemicals within porous media in relation to their efficiency in solving scale problem. However, the mechanisms underpinning scale inhibitors performance are not well published. Some research works have shown theoretically that not all scale inhibitors pumped into the formation adsorb onto the formation rock. Some of the inhibitors may adsorb on produced loose sand grains or colloidal fine sand particles which float and flow within the pore spaces along with the scale inhibitor mostly in unconsolidated reservoirs This paper provides a review of research work on the effect of produced loose sand or colloidal fine particles flow on polyphosphonates and polyphosphinopolymer scale inhibitors performances during crude production.

Towards Sustainable Lactic Acid Production: Avoiding Gypsum as a Byproduct by using Selective Liquid-Phase Adsorption

The utilization of biomass is one of the major challenges for the transition from fossil to renewable resources. Often, the separation of the desired product from the reaction mixture is the most energy-intensive step. Liquid-phase adsorption is a promising separation technology that could significantly improve downstream processing in biorefineries. Highly hydrophobic adsorbents were applied for the separation of lactic acid (LA) from aqueous solutions and to avoid the formation of gypsum as a byproduct. High uptakes and selectivity were obtained in single-solute and co-adsorption experiments. Porous hyper-crosslinked polymers (HCP) and polymer-based spherical activated carbon performed best and showed excellent selectivity for the selective removal of LA. Desorption experiments revealed that HCP was the ideal adsorbent for the separation of LA from aqueous solution and enabled the production of gypsum-free LA.

Modeling of the static batch desorption and dynamic column elution of geniposidic acid from a porous anion-exchanger

For several decades, plenty of iridoid glycosides including geniposide (GS) and geniposidic acid (GSA) in the gardenia yellow pigment extraction waste water was not recovered effectively. This study is aimed to supply an efficient GSA recycling route. In this study, a model incorporating a superficial desorption rate constant was applied to the batch GSA desorption process, i.e., recycling, for verification. Then, the model was further developed to research the feasibility in dynamic column elutions simulation through porous uniform media. The simulation approach was done by coupling velocity field and mass transfer equations using COMSOL Multiphysics™ Finite element method, with appropriate mesh refinement was employed to solve the equation system. The HCl solutions ranging from 0.03 mol/L to 0.06 mol/L were used to desorb/elute the GSA from a presaturated polymeric porous anionic resin D08. Good results were accomplished in terms of ion exchange desorption rate and GSA recovery. The pore diffusion model (PDM) considering counter ion was established to describe the desorption/elution kinetics in the batch/column experiment. By the least square fitting method, the superficial desorption rate constant K_d of GSA/HCl reaction on the ion-exchange sites of porous resin was fitted to 0.116 L/(mol s). Subsequently, this value was sequentially applied in the simulation of the dynamic elution process. The individual pore diffusion coefficients for GSA and Cl^- were estimated to be 5.07 × 10^-10 and 1.77 × 10^-9 m²/s, respectively. In order to validate the simulation feasibility of this pore diffusion model to a dynamic column elution process, the effects of HCl concentration, flow rate and column's height/diameter ratio on the column performance were investigated systematically. The results from this work should serve as motivation for further experimental and theoretical study in the scaling-up of GSA purification process. Finally, repeated adsorption-elution column cycles were simulated by the PDM model well.

Adsorption behavior of levulinic acid onto microporous hyper-cross-linked polymers in aqueous solution: Equilibrium, thermodynamic, kinetic simulation and fixed-bed column studies

The recovery of levulinic acid (LA) from aqueous solution and actual biomass hydrolysate by a microporous hyper-cross-linked polymer, SY-01, was investigated for the first time under batch and fixed-bed column conditions. The results showed that the optimum pH should be in the acidic range (pH < 3.0) without adjusting the pH. In the single-component system equilibrium study, the Langmuir isotherm model fits the LA adsorption onto SY-01 resin better than the Freundlich isotherm model, indicating that LA adsorption onto SY-01 resin under the concentration range studied is a monolayer homogeneous adsorption process. The maximum adsorption capacity of LA onto SY-01 resin decreased with increasing temperature, ranging from 103.74 to 95.70 mg/g. The obtained thermodynamic parameters suggested that the adsorption of LA on SY-01 was spontaneous (ΔG⁰<-3.788 kJ/mol), and exothermic (ΔH⁰ = -11.764 kJ/mol). For kinetic study, the adsorption of LA onto SY-01 resin at various operating conditions follows the pore diffusion model and the intraparticle diffusion is the rate-limiting step for the adsorption of LA onto SY-01 resin. The effective pore diffusivity was dependent upon temperature, but independent of initial LA concentration, and were 3.306 × 10^-10, 5.274 × 10^-10 and 7.707 × 10^-10 m²/s at 298, 318 and 338 K, respectively. In desorption process, the recovery efficiency of LA from SY-01 resin was 99.39%, and LA concentration in the eluent was raised 2.97-fold. In conclusion, our results show that the SY-01 resin has potential application in product recovery of LA from biomass hydrolysate.