Department of Petroleum Engineering, College of Petroleum and Geosciences, King Fahd University of Petroleum and Minerals, 31261, Dhahran, Saudi Arabia.
Sci Rep. 2023 May 29;13(1):8669. doi: 10.1038/s41598-023-36010-w.
Ordinary Portland cement (OPC) has introduced different environmental and technical issues. Researchers tried either adding new materials to cement or developing alternatives for both technical and environmental challenges. Hematite as a weighting agent is used to increase cement slurry density. Heavy particles sedimentation in cement and geopolymer slurries is a serious issue which creates heterogenous properties along the cemented section. This work presents a new class of geopolymers using both hematite and Micromax as weighting materials for high density well cementing applications. The first system used only hematite while the other system used both hematite and Micromax. The main goal behind using Micromax with hematite is to check the possibility of eliminating the sedimentation issue associated with hematite in geopolymers. Moreover, the effects of adding Micromax on different FFA geopolymer properties were also evaluated. Different mixtures of retarder, retarder intensifier and superplasticizer were introduced to increase the thickening times of the developed geopolymer systems. The results showed that adding Micromax to hematite decreased the average density variation from 12.5% to almost 3.9%. Micromax addition reduced plastic viscosity by 44.5% and fluid loss by 10.5%. Both systems had a close performance in terms of strength, elastic properties, and permeability. The thickening time was 390 min for the hematite system and 300 min for the mixed system using the proposed additives mixtures.
普通波特兰水泥 (OPC) 带来了不同的环境和技术问题。研究人员要么尝试在水泥中添加新材料，要么开发新技术和替代材料来应对环境挑战。赤铁矿作为加重剂用于增加水泥浆的密度。重颗粒在水泥和地质聚合物浆中的沉降是一个严重的问题，它会在水泥固井段产生不均匀的性质。本工作提出了一类使用赤铁矿和 Micromax 作为加重材料的新型地质聚合物，用于高密度固井应用。第一个体系仅使用赤铁矿，而另一个体系则同时使用赤铁矿和 Micromax。在地质聚合物中使用 Micromax 与赤铁矿的主要目的是检查是否可以消除赤铁矿在地质聚合物中沉降的问题。此外，还评估了添加 Micromax 对不同 FFA 地质聚合物性能的影响。引入了不同的缓凝剂、缓凝增强剂和超塑化剂混合物来增加所开发的地质聚合物体系的稠化时间。结果表明，在赤铁矿中添加 Micromax 可将平均密度变化从 12.5%降低到几乎 3.9%。Micromax 的添加使塑性粘度降低了 44.5%，滤失量降低了 10.5%。这两个体系在强度、弹性性能和渗透率方面都具有相近的性能。使用所提出的添加剂混合物，赤铁矿体系的稠化时间为 390 分钟，混合体系的稠化时间为 300 分钟。
