Synergistic alginate chelation and semi-interpenetrating network for advanced wellbore stabilizing hydrogels
Year: 2025
Type: article
Abstract: In situ plugging hydrogels represent a promising strategy to combat wellbore instability in fractured formations. Despite their potential, they often fail due to unpredictable gelation kinetics and inadequate mechanical strength under downhole conditions. Here, we introduce an alginate-based hydrogel (Alg-gel) engineered with an acid-triggered, multi-crosslinking mechanism that constructs a biodegradable shield directly within fractures. This system integrates sodium alginate (SA) with hydroxypropyl guar gum (Hpg) to form a primary semi-interpenetrating network. The critical innovation lies in the synergistic use of D-gluconic-δ-lactone (GDL) and CaCO 3 , which enables precise, sustained release of Ca 2+ ions. These ions subsequently coordinate with guluronate blocks in SA, establishing a secondary network that embeds residual CaCO 3 as reinforcing scaffolds. This multi-network architecture results in a storage modulus increase by orders of magnitude and reduces filtration loss by up to 89.3% as gelation proceeds from 30 to 180 minutes. Structural evolution from a sparse framework to a densely interlocked lamellar assembly was directly visualized, validating the tunable nature of the complexation process. The exceptional plugging performance and controllable gelation kinetics position Alg-gel as a superior lost circulation material, with broader implications for profile modification and gas channeling mitigation.
Source: Petroleum Science
Authors: Zhao-Jie Wei, Ying-Long Duan, Mao-Sen Wang, Ying-Hui An, Wen-Jing Qin, Ming-Yi Guo
Language: English
Subfield: Ocean Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: diamond
Awards: 钻井液高温成膜疏水性井壁构建与机理研究, G6232471715
OpenAlex ID: W4416509803