In situ recovery of resources from waste repositories

在历史上，社会将大量的工业、市政、冶金和采矿废物处理到地下，并在地质上储存了大量有价值的材料，如金属和能源(以生物质和聚合物的形式)。因此，与其将这些废物库视为遗留废物问题和长期负担，不如改变观念，将这些设施视为未来回收的“资源中心”。拟议的研究旨在促进开发一个与从现有废物储存库回收资源有关的新的和令人兴奋的研究领域，并试图解决以下中心问题：资源，特别是有价值的元素(例如金、钯、银、铜、铅、锌、钴、镍、锡和铬)、用于清洁能源和其他环境应用的‘E-tech’元素(例如钕和其他稀土元素)和能源(通过强化甲烷产生)能否在材料就地时通过淋滤和其他处理方法回收，从而避免需要积极开采材料，从而最大限度地减少对生态和环境的影响？支持这一点的基本地学研究问题是：我们如何理解和操纵地质储存库中废物的就地生物地球化学，以回收资源？研究背后的基本原理是研究新的资源回收技术，其对环境的影响低于对废物或原始矿石的积极(挖掘和加工)开采。原地浸出的概念和技术已经在采矿业中开发出来，用于回收铀和铜，并通过循环溶液提取元素和/或刺激和增强微生物浸出。将这一概念应用于从废物储存库回收资源的可能性以前没有得到充分讨论。废物的成分、矿物质和质地与矿石非常不同，因此需要新的科学来了解和开发浸出方法来溶解有价值的成分。我们将考虑从英国垃圾库中现有的各种废物中提取资源，包括工业和商业废物(预计金属含量丰富)、焚化炉和燃料灰、矿物废物和市政废物，以研究就地浸出的想法。我们特别希望在拨款期间，找出哪些类型的堆填区废物可相对丰富某些资源，并集中研究如何从这些废物中回收。我们预计，原地浸出可以避开阻碍实现废物库资源潜力的许多问题，不仅在英国，而且在国际上都会产生重要影响。此外，我们的目标不仅是调查通过原地浸出回收资源的方法，而且还调查如何从生命周期、人类健康和生态系统服务成本以及公众舆论方面适当地对此类过程进行基准测试(我们预计这种过程对环境和人类健康的影响可能会大大降低)，以便与‘传统’挖掘和处理垃圾填埋场开采垃圾填埋场资源以及与传统开采相同资源进行比较。其目的是提供证据，证明这些技术不仅在技术上可行，而且与传统技术相比影响较小，利益攸关方可以接受，因此是未来废物管理的一种可行和适当的办法。

Having historically disposed of vast quantities of industrial, municipal, metallurgical and mining waste into the ground, societies have put into geological storage an enormous amount of resources in a range of materials of value such as metals and energy (in the form of biomass and polymers). Therefore, instead of considering these waste repositories to be a legacy waste issue and a long-term liability, a paradigm shift is required to view these installations as "resource hubs" for future recovery. The proposed research aims to contribute towards the development of a new and exciting research field related to resource recovery from existing waste repositories and seeks to address the following central question: Can resources, specifically elements of value (e.g. Au, Pd, Ag, Cu, Pb, Zn, Co, Ni, Sn and Cr), 'E-tech' elements used in clean energy and other environmental applications (e.g. neodymium and other rare earth elements) and energy (through enhanced methane generation) be recovered by leaching and other treatments whilst the material lies in situ, thus avoiding the need to actively mine the material and thereby minimising ecological and environmental impacts?The fundamental geoscience research question that underpins this is:How can we understand and manipulate the in situ biogeochemistry of the waste within the geological repository to recover resource?The rationale behind the research is to examine new technologies for resource recovery with a lower environmental impact than active ('dig and process') mining of wastes, or of virgin ores.The concept and technology of in situ leaching has been developed in the mining industry for recovery of uranium and copper, and is done by circulating solutions to extract the elements and/or stimulating and enhancing microbial leaching. The possibility of transferring this concept for application to recovery of resource from waste repositories has not been fully addressed previously. Wastes display diverse compositions, mineralogies and textures very different to that of ores and thus will require new science to understand and develop leaching methods to solubilise valuable components.We will consider resource extraction from the full range of wastes currently in UK waste repositories including industrial and commercial waste (anticipated to be metal-rich), incinerator and fuel ash, mineral wastes and municipal wastes to examine the idea of in situ leaching. We are particularly keen to identify during the grant which types of landfilled waste streams might be relatively enriched in certain resources and focus the research on recovery from these wastes as a starting point. We envisage that in situ leaching could sidestep many of the problems that prevent realisation of the resource potential of waste repositories, with important impacts not only in the UK but internationally. Furthermore, our aim is to not only investigate means to recover resource through in situ leaching but to also investigate how we can appropriately benchmark such processes (which we anticipate may have substantially lower environmental and human health impacts) in terms of life-cycle, human health and ecosystems service costs as well as public opinion for comparison to retrieval of landfilled resources by 'conventional' dig-and-process landfill mining and against conventional mining of the same resources. This aims to provide evidence to demonstrate not only that the techniques are technically feasible but that they offer reduced impact compared to conventional technologies, are acceptable to stakeholders and thus are a feasible and appropriate approach to future management of wastes.