Band 38, Heft 1

Fine migration is a serious problem in petroleum reservoir that causes damage to the reservoir and production equipment. One of the methods to solve this problem is using nanotechnology. Nanoparticles can reduce fine migration by various mechanisms such as reducing the zeta potential, changing the total interaction energy between surfaces, pH, and roughness of the particle’s surfaces. This study presents a review of the methods such as sand pack test, core flood test, and proppant test that study the nanoparticles’ influence on fine migration. Also, there are two different scenarios for the use of nanoparticles to mitigate fine migration. One of these scenarios is the co-injection of nanoparticles and particles suspended fluid, and another scenario is the initial injection of nanoparticles into the porous media (pre-flush). The results of the studies have shown that pre-flush of nanoparticles has a better effect on the control of fine migration.

This article reviews the common well cements and describes the basic nature of the cement-formation bond in zonal isolation and its effects on the mechanical and hydraulic performance. The cements are Classes G and H Portland well cements. The cement-formation interface bonding mechanism is a combination of the mechanical indentation of the cement hydrates that interlock to the formation surface and the chemical reactions that occur between the cement slurry and constituents of the rock grains. Mechanical indentation occurs as the hydration products epitaxially grow at the formation surface. The degree to which each of these processes accounts for the formation of the bond is unknown. Here we provide a review of well cement and cement-formation bonds and a discussion of the possible factors that are proposed to influence the microstructural, chemical, and mineralogical properties at the cement-formation interface. In addition, we present some findings about how these factors affect the mechanical and hydraulic performance of the cement-formation bond in zonal isolation.

Difficult-to-biodegrade fractions (DBFs) generated from the biological treatment of food waste (FW) account for approximately 30% of the actual waste. These wastes are difficult to degrade or are considered indigestible residues of the aerobic and anaerobic fermentation treatment of FW treatment facilities. The currently applied disposal routes for DBFs exert environmental pressure and underutilize waste as resources. Therefore, these challenges must be overcome. An innovative strategy for the enhancement of the energy value and beneficial products from FW and the associated DBFs is proposed in this review. We propose conceptual future optimization routes for FW and DBFs via three types of technology integration. Pyrolysis techniques thoroughly treat DBFs to produce various value-added bio-energy products, such as pyrogenic bio-char, syngas, and bio-oil. Anaerobic digestion treats FW while utilizing pyrolysis products for robust performance enhancement and bio-methane upgrade. This holistic route offers conceptual information and proper direction as crucial knowledge for real application to harness the inherent resources of waste streams generated from FW treatment facilities.

The biomass-to-liquid (BtL) process is a promising technology to obtain clean, liquid, second-generation biofuels and chemicals. The BtL process, which comprises several steps, is based upon the gasification of biomass and the catalytic transformation of the syngas that is obtained via the Fischer-Tropsch synthesis (FTS) reaction, producing a hydrocarbon pool known as syncrude. The FTS process is a well-established technology, and there are currently very large FTS plants operating worldwide that produce liquid fuels and hydrocarbons from natural gas (NG) (gas-to-liquids, GtL process) and coal (coal-to-liquids, CtL process). Due to the limited availability of local biomass, the size of the BtL plants should be downscaled compared to that of a GtL or CtL plant. Since the feasibility of the XtL (X refers to any energy source that can be converted to liquid, including coal, NG, biomass, municipal solid waste, etc.) processes is strongly influenced by the economies of scale, the viability of small-scale BtL plants can be compromised. An interesting approach to overcome this issue is to increase the productivity of the FTS process by developing reactors and catalysts with higher productivities to generate the desired product fraction. Recently, by integrating membrane reactors with the FTS process the gas feeding and separation unit have been demonstrated in a single reactor. In this review, the most significant achievements in the field of catalytic membrane reactors for the FTS process will be discussed. Different types of membranes and configurations of membrane reactors, including H 2 O separation and H 2 -feed distribution, among others, will be analyzed.

The potential impact of climate change is widely known as having serious consequences. The themes of water desalination and gas separation are closely related to the environment and energy industry. Graphene-based membranes are promising filtration devices for the two tasks. This review aims to supply a comprehensive overview of the recent computational studies investigating the performance of graphene-based membranes used in water desalination or gas separation. With the use of computational methods, the literature covered finds evidence for key factors, such as pore shape and density, affecting the performance of the investigated membranes. The reviewed studies are expected to act as an impulse towards more computational studies and eventually actual design of graphene-based membranes for water desalination and gas separation.

Supercritical water (SCW) is a green solvent. The supercritical fluids have been increasingly concerned and studied in many areas such as SCW gasification, biofuel production, SCW hydrothermal conversion, organic wastes treatment and utilization, nanotechnology, etc. Because of the severe circumstances and rapid reactions in supercritical water, it is difficult for experimental researchers to disentangle various fundamental reaction steps from the intermediate and product distributions. From this perspective, molecular dynamics (MD) simulation based on quantum chemistry is an efficient tool for studying and exploring complex molecular systems. In recent years, molecular simulations and quantum chemical calculations have become powerful for illustrating the possible internal mechanism of a complex system. However, now there is no literature about the overview of MD simulation study of the system with SCW. Therefore, in this paper, an overview of MD simulation investigation applied in various systems with SCW is presented. In the current review we explore diverse research areas. Namely, the applications of MD simulation on investigating the properties of SCW, pyrolysis/gasification systems with SCW, dissolution systems and oxidation systems with SCW were summarized. And the corresponding problems in diverse systems were discussed. Furthermore, the advances and problems in MD simulation study were also discussed. Finally, possible directions for future research were outlined. This work is expected to be one reference for the further theoretical and molecular simulation investigations of systems involving SCW.