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Gas operations generate large volumes of wastewater, necessitating efficient water management schemes. This study evaluates a forward osmosis (FO) pilot plant for volumes reduction of gas industry process water (PW). The osmotic pressure difference between seawater (40 g/L Total Dissolved Solids (TDS)) and low salinity (2 g/L TDS) PW is used for the osmotic concentration (OC). In the OC, PW volumes get reduced, while diluted draw solution (DS) is directly discharged, obviating the high-energy DS recovery step. A thin-film composite hollow fiber (HF) FO membrane was tested under FO mode using synthetic solutions to assess the performance on the OC unit. Subsequently, the pilot unit was subjected to PW feed for 48 h of continuous operation, primarily to evaluate water flux, reverse solute flux (RSF), and membrane fouling. The cleaning requirement to remove contaminants from the membrane surface was examined. The membrane achieved a water flux and RSF between 11.5 to 6.43 LMH and 38.57 to 9.45 mmol h−1m−2, respectively at feed recovery rates between 60 and 90%. The membrane achieved a water flux of 10 LMH, which slightly decreased to 9.6 after 48 h of operation, mainly due to inorganic scaling. Lastly, cleaning with citric acid succeeded in recovering the initial water flux.

The advancement of superplasticizers is considered a significant innovation in the construction sector, which has facilitated the creation of high-quality concrete. The construction industry has a pressing need for the development of high-performance concrete. Notwithstanding their utility, the present superplasticizers encounter a number of obstacles, including but not limited to challenges in regulating the water–cement ratio, flowability, segregation, and expense. It is imperative for both academia and the construction industry to prioritize addressing these challenges. The potential of developing superplasticizers with exceptional properties has attracted the interest of many researchers in the past few years. Accordingly, the objective of this paper is to provide a comprehensive review of the state of the art of superplasticizers, with a particular emphasis on the evolution of various types of superplasticizers, plasticizing mechanisms, and their applications in the construction sector. Electrokinetics, rheology, and flow properties of cements and concrete mixtures containing different superplasticizers are critically evaluated, and various parameters such as zeta potential, adsorption, flowability, hydration, and non-Newtonian behavior are discussed. Finally, future perspectives of the impact of using superplasticizers on cement paste, water-to-cement ratio, and enhancing the overall performance of concrete have been outlined.

Recently, cross-linked polymers such as polyacrylamide (PAM)/polyethylenimine (PEI) have been used in conformance control applications to replace conventional lost circulation materials (LCMs). The objective of this work is to introduce functionalized silica to reinforce PAM and enhance gel performance under high temperature high pressure (HTHP) conditions. A system was developed using PAM/triamine silica (TAS) combined with nanosilica (NS) to replace the conventional PEI as a cross-linker. Polymer systems consisting of 9 wt % PAM and polyacrylamide tert-butyl (PAtBA) with various concentrations of PEI, TAS, and NS (50 nm) were used to produce mature gels at 130 °C. The results have shown that TAS has formed a gel with code “E” on the Sydansk coding system. Adding a low concentration (1–2 wt %) of 50 nm silica has eliminated the settling of microsized TAS and produced a reinforced gelant system with code “I”. The cross-linking was accomplished via an amine group similar to the PEI mechanism with the advantage of strength and stability due to the presence of silica. The increase in the gel strength of the PAM/TAS formulation depends on the amount of NS; the gel strength of the PAM/PEI system has increased from 1670 Pa to more than 9000 Pa for the PAM/TAS/NS system. The new formulation is compatible with high salinity water, and a chelating agent could be introduced to prevent formation damage.

Nanoparticles display great potential in heat transfer applications due to their impressive thermophysical properties and unique properties, which enhances the performance of a system. This review delves into the thermophysical characteristics of various nanoparticles, including MXenes, MOFs, CNTs, and graphene, and understand the importance of nanoparticles in heat transfer. MXenes are a relatively new nanoparticle that shows a lot of potential in heat transfer applications; yet, when compared to MOFs, the results demonstrated weren’t nearly as impressive because of their larger area and pore size. Conversely, the superior heat transfer performance of CNTs and graphene led to their widespread use in various applications. Thermal conductivity enhancements of 30.6, 64, and 64% for MXene, graphene, and MWCNT were observed when nanoparticles were dispersed in water, indicating better heat transfer for CNT and graphene nanoparticles. Nonetheless, even though some displayed better results than others, each nanoparticle is unique and affects the system distinctively. Additionally, in this review, nanoparticles were investigated computationally, and the results were similar to experimental findings, offering further insight into which nanofluids most effectively influence heat transfer. Overall, nanoparticles enhance system efficiency, making nanofluids reliable for diverse processes despite ongoing challenges. However, nanoparticles in many systems are still being discovered and face many challenges. Therefore, future research should try to focus on studying the effects of nanoparticles in new and large-scale applications and seek solutions to the challenges faced by certain nanoparticles to improve these systems.

Wellbore strengthening has been introduced recently to resolve lost circulation problems by improving the fracture gradient and hence extending the mud window. Polymeric cross-linkable solutions showed outstanding strength with high thermal stability at elevated temperatures. In this study, silica with different sizes is used to reinforce the polymer solutions. The objective of this work is to investigate the effect of nanosilica sizes (8, 20, 50, and 85 nm) and concentrations (0.1–2 wt %) on the stability and viscoelastic behavior of polyacrylamide (PAM) cross-linked with polyethyleneimine (PEI) at 130 °C. Moreover, the effect of PAM Mwis also studied. The results have shown that nanosilica has reinforced the PAM/PEI solution; the gel of the base polymeric solution has upgraded from code “F” to codes “G” and “I” based on the Sydansk coding system. The strongest gel was formed with the addition of 2 wt % of 50 nm silica to the polymer base solution which enhanced the gel strength by more than 300%. Zeta potential confirmed that 50 nm silica was the most stable among the other sizes. Gel strength was observed to increase upon increasing the size of nanosilica initially, and then, it has decreased which gave an optimum nanosilica size of 50 nm. The stability of silica particles in the system is suggested as an explanation for this drop in strength. The interaction between silanol and carbonyl groups via hydrogen bonding is proposed as the controlling mechanism of gel formation. The results suggest the importance of selecting the proper size and content of nanosilica for reinforcing PAM/PEI gels.

Highly porous modified clay material with large surface area known as “Filtralite” was used as a filler for the preparation of polysulfone (PSf) composite membranes. Filtralite concentration in the membrane composition was varied from 0, 1, 2 and 3%. The prepared membranes were characterized and their permeation performances were identified using pure water, sodium alginate and humic acid solutions. It was found that the addition of Filtralite to PSf increased the water uptake, hydro-philicity, porosity and surface roughness of the membranes. The obtained results showed that both permeation and antifouling properties of the prepared composite membranes were enhanced with added Filtralite content to the PSf membrane. The experimental results showed that a maximum of 2% Filtralite content can be added for better membrane performances, beyond which the membrane characteristics start to degrade.