Electricity generated through coal-based Thermal Power Plants (TPPs) has played a pivotal role in shaping modern civilization, revolutionizing industries, and improving the quality of life for billions of people worldwide. These TPPs contribute to about 37%–40% of the global energy requirements. Energy production, in turn, has a direct impact on the economy of any country. Apart from this boon to humankind, these TPPs combusting coal as their primary fuel also have specific environmental impacts, the major ones being water, air, and soil pollution due to unscientific disposal of high-quantity fly ash produced yearly. If we can put this ash to good use, it may assist us in mitigating the pollution caused by it. Although there are many conventional uses of fly ash, such as a pozzolanic material in the cement industry, more pathways need to be discovered to balance the high generation quantities with consumption. Therefore, a detailed description of its use in potential geoliner applications is presented in this article. A geoliner or a landfill liner acts as a virtually impenetrable layer to mitigate the leachate penetration into the underneath subsoil and groundwater, thus preventing contamination. There are presently some studies that support the use of only fly ash in such applications. Nevertheless, the properties of the geoliners using it are not so good to significantly mitigate environmental degradation owing to its high permeability and low densification tendency. The bentonite conventionally used has limited deposits and is mined intensively for its use as a natural sealant. Their deposits must also be conserved, and an alternative material that may serve similar application benefits, like bentonite, must be selected. The desired aim can be fulfilled if we blend this combustion residue with other suitable materials (such as kaolinite clay) with low permeability. Thus, the article focuses on the possibilities of blending fly ash with different clays for geoliner construction to improve the individual properties of fly ash. This will contribute to developing a scope for future scientific research in deploying these blends in natural membrane materials for various industries. Different types of geoliners that are designed to contain the disposed-off waste are also explained in detail. Additionally, a glimpse of the global fly ash market is put forward to depict its importance for various industries in this technologically advancing world. This article profoundly observes an overall environmental management aspect regarding waste utilization.

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中文翻译：

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通过将粉煤灰与高岭土替代品混合，实现垃圾填埋场可持续的地质衬垫建设：对印度情况的回顾

燃煤火力发电厂（TPP）产生的电力在塑造现代文明、变革工业和改善全球数十亿人的生活质量方面发挥了关键作用。这些 TPP 约占全球能源需求的 37%–40%。反过来，能源生产对任何国家的经济都有直接影响。除了造福人类之外，这些以煤炭为主要燃料的TPP也会产生特定的环境影响，主要是由于每年产生的大量粉煤灰处理不科学而造成的水、空气和土壤污染。如果我们能够充分利用这些灰烬，它可能会帮助我们减轻由此造成的污染。尽管粉煤灰有许多常规用途，例如水泥工业中的火山灰材料，但仍需要发现更多途径来平衡高发电量与消耗。因此，本文详细描述了其在潜在地质线应用中的使用。地质衬垫或垃圾填埋场衬垫充当几乎不可渗透的层，以减轻渗滤液渗透到下面的底土和地下水中，从而防止污染。目前有一些研究支持在此类应用中仅使用飞灰。然而，由于其高渗透性和低致密化趋势，使用它的地质衬垫的性能不太好，无法显着减轻环境退化。传统使用的膨润土储量有限，并且被集中开采以用作天然密封剂。它们的沉积物也必须得到保护，并且必须选择具有类似应用优势的替代材料，例如膨润土。如果我们将这种燃烧残渣与其他合适的低渗透性材料（例如高岭土）混合，就可以实现预期的目标。因此，本文重点讨论将粉煤灰与不同粘土混合用于地质衬垫施工以改善粉煤灰的单独性能的可能性。这将有助于开拓未来科学研究的范围，将这些混合物应用于各个行业的天然膜材料中。还详细解释了旨在容纳废弃废物的不同类型的地质衬垫。此外，还对全球粉煤灰市场进行了概述，以描述其在这个技术进步的世界中对各个行业的重要性。本文深刻观察了废物利用的整体环境管理方面。

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