ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Combined effect of quaternary amine [NR₄]⁺ solution and Polyanionic cellulose on shale inhibition behavior

Shaine Mohammadali Lalji, Syed Imran Ali, Muhammad Arqam Khan, Meichun Li, and Muneeb Burney

Department of Petroleum Engineering, NED University of Engineering & Technology, Karachi, Pakistan

E-mail: shaine@neduet.edu.pk

Received: 29 May 2024  Accepted: 10 July 2024

Abstract:

In drilling, mitigating wellbore instability issues in reactive shale formations is crucial and takes top priority. These instabilities often lead to significant disruptions in drilling operations, resulting in loss of time and increased operational costs. This study is aimed at mitigating these challenges, with a primary focus on reducing filtration loss volume and enhancing wellbore stability within shale formations. In this study, the filtration properties of water-based mud along with Ranikot shale stability were investigated in presence of PAC and Amine. In this revolutionary study, the synergistic effect of two additives on the filtration properties of water-based mud and Ranikot shale was comprehensively investigated and visualized through 3D surface plots. A total of 13 distinct mud samples were meticulously formulated using Central Composite Design, a pivotal subset of response surface methodology. The result of the study shows that there were no drastic variations in the mud weight recorded with changes in concentration of PAC and amine. Moreover, sample 4 with least concentration of both additives demonstrates a highest fluid loss volume of 13.5 mL/30 min, which highlights the importance of optimal concentration of PAC and amine in WBM. Furthermore, this low concentration sample formed a mud cake with rough and thick texture, exhibiting a high permeability of 0.54371 µD. In contrast, samples with high concentrations were extremely successful in maintaining a low fluid loss volume and forming a dense and compacted mud cake. Additionally, the combined influence of these particle on enhancing the hydrophobic behavior of the shale sample was also investigated. Sample 4 with least particles concentration demonstrated a contact angle of 37.398°, while the highest contact angle of 86.792° was exhibited by sample with greater concentration of amine and PAC. The result showed that the high concentration of PAC and amine in the mud sample led to a substantial enhancement of the shale hydrophobic character. This shows that when PAC and amine interact with the shale pellets it reduces the affinity for water and thereby increases its resistance to water ingress, which play a pivotal role in wellbore stability. The study’s outcomes underscore the remarkable efficacy of PAC and amine in considerably reducing the filtrate loss, thereby leading to enhanced drilling efficiency and operational performance.

Keywords: Amine; Central composite design; PAC-L; Response surface methodology; Shale

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-024-03608-x

Chemical Papers 78 (13) 7487–7503 (2024)