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ASP flooding wastewater contains crude oil, suspended solids, anionic polymers and surfactants, with high viscosity, high zeta potential, difficult demulsification, flocculation and slow separation and sedimentation. In order to solve the problem of wastewater treatment of ASP flooding in oil fields, a magnetic branched core was prepared from ethyl silicate (TEOS), nano Fe3O4 and aminopropyl triethoxysilane (APTES), and then reacted with polyamine and methyl acrylate to synthesize the magnetic hyperbranched molecule FSNMN with demulsification ability. Using acrylamide (AM), acryloxyethyl trimethylammonium chloride (DAC) and maleic anhydride (MA) as raw materials, cationic polymer long chain (CAMHA) with flocculating properties was synthesized and grafted with hyperbranched molecules. The demulsification flocculation ability of the product regarding ASP flooding wastewater was evaluated, and the demulsification flocculation mechanism was summarized. The results showed that the average molecular weight of 3-FSNMN4-C was 4.7 million, the cationic degree was 20.5%, and the saturation magnetization was 20 EMU/g. The removal rate of oil and suspended solids was 93.82% and 91.95% respectively when the simulated sewage was treated by magnetic field for 30 min. Magnetic hyperbranched star chain polymer provides a solution to the serious ecological environment problems caused by ASP flooding.

Nanofluid-enhanced oil recovery (EOR) technology is an innovative approach to enhancing oil production in oilfields. It entails the dispersion of nanoparticles within a fluid, strategically utilizing the distinctive properties of these nanoparticles (NPs) to engage with reservoir rocks or crude oil, resulting in a significant enhancement of the oil recovery rate. Despite the notable advantages of nanofluid EOR technology over conventional oil recovery methods such as binary and ternary flooding, practical implementations continue to grapple with a range of pressing challenges. These challenges encompass concerns regarding the economic viability, stability, and adaptability of nanomaterials, which pose significant barriers to the widespread adoption of nanofluid EOR technology in the oil field. To tackle these challenges, addressing the current issues may involve selecting simpler and more readily available materials coupled with straightforward material modification techniques. This approach aims to more effectively meet the requirements of large-scale on-site applications. Within this framework, this review systematically explores commonly employed nanofluids in recent years, including inorganic nanofluids, organic nanofluids, and composite nanofluids. It categorizes the research advancements in optimizing modification techniques and provides a comprehensive overview of the mechanisms that underpin nanofluid EOR technology and its practical applications in oilfields. This comprehensive review aims to offer valuable references and serve as a solid foundation for subsequent research endeavors.

Graphene and its derivatives, characterized by their ultra-high water flux, unique physicochemical properties, and tunable layered structures, have increasingly emerged as a new generation of membrane materials for wastewater treatment. In this study, a novel membrane material was fabricated via vacuum filtration using BiOCl-doped graphene oxide (GO) modified with diethylenetriamine. This modified GO membrane exhibits excellent wettability, with a water contact angle of 0° in air and an oil contact angle of 144.5° underwater. It demonstrates a separation efficiency of 95.2% for kerosene emulsified oil and 90.2% for crude oil emulsified oil. Additionally, this paper provides a detailed investigation into the mechanism by which the membrane material separates emulsified oils, offering new insights for the treatment of oily wastewaters.

As most oilfields of China turn into the later stage of high water cut, Water shutoff has been an important means to increasing and maintaining oil output in the oilfield. Oil solubel resin-dual crosslinked-gelatinous selective water shutoff agent (ORG) is a good choice. After the formula of ORG is determined, the plugging ability of plugging core and plugging performance of plugging agent are simulated. This paper clarifies the role of ORG plugging agent in the formation, provides support for the application of ORG plugging agent and provides technical support for high and stable oil production.

The gas well in Jilin oil field has the characteristics of large temperature variation range and high condensate oil content. So the foam drainage agent of the gas well in Jilin oil field needs to have the performance of oil resistance and less effected by temperature. In this paper, a main foaming agent named lauramidopropyl betaine (LAB) and two kinds of auxiliary foaming agent named sodium alcohol ether sulphate (AES) and lauramidopropylamine oxide (LAO). Through the evaluation of the static foaming capacity and dynamic liquid carrying capacity, the AES is more suitable for LAB. The foaming agent with 70% LAB and 30% AES has 138mm foam height with ROSS-Miles equipment; stirring foam volume can reach 480mL, the half-life of foam is 520s. When the ventilation volume is 8L/min the liquid carrying capacity of 10% of the condensate oil content reached 82g. When the foaming agent concentration is 2%, the liquid carrying capacity of 10% of the condensate oil content reached 75g. When the aeration rate reaches 8-10L/min, the liquid carrying capacity of foam drainage agent can reach the best. The foam drainage agent can retain the performance after 120°C aging for 12h, these performances above can satisfy the requirements for gas well foam drainage in Jilin Oil Field.

Zokors, an Asiatic group of subterranean rodents, originated in lowlands and colonized high-elevational zones following the uplift of the Qinghai–Tibet plateau about 3.6 million years ago. Zokors live at high elevation in subterranean burrows and experience hypobaric hypoxia, including both hypoxia (low oxygen concentration) and hypercapnia (elevated partial pressure of CO 2 ). Here we report a genomic analysis of six zokor species (genus Eospalax ) with different elevational ranges to identify structural variants (deletions and inversions) that may have contributed to high-elevation adaptation. Based on an assembly of a chromosome-level genome of the high-elevation species, Eospalax baileyi , we identified 18 large inversions that distinguished this species from congeners native to lower elevations. Small-scale structural variants in the introns of EGLN1 , HIF1A , HSF1 and SFTPD of E. baileyi were associated with the upregulated expression of those genes. A rearrangement on chromosome 1 was associated with altered chromatin accessibility, leading to modified gene expression profiles of key genes involved in the physiological response to hypoxia. Multigene families that underwent copy-number expansions in E. baileyi were enriched for autophagy, HIF1 signalling and immune response. E. baileyi show a significantly larger lung mass than those of other Eospalax species. These findings highlight the key role of structural variants underlying hypoxia adaptation of high-elevation species in Eospalax . Comparative analysis of whole-genome sequencing of six zokor species that live at different altitudes show the contribution of deletions and inversions to adaptation to high altitude in these subterranean rodents.