ASPIRE - Accelerated Supergene Processes in Repository Engineering

英国在未来的骨料、关键矿物和元素供应方面面临着严峻的战略挑战。与此同时，英国必须可持续地管理每年产生的数百万吨工业、采矿和矿物废物（IMMWs）。预计未来几年产生的这些废物的数量将增加，特别是(i)燃烧生物质和城市固体废物产生的灰烬，以及（ii）受污染的疏浚。这些废物将继续被填埋，尽管它们往往含有宝贵的资源，如高浓度的关键金属、土壤宏量营养素和有用的矿物成分，其中一些会积极减少大气中的二氧化碳。ASPIRE（存储库工程加速超基因过程）研究项目的基本目标是开发一种可持续的方法，通过这种方法，灰烬、受污染的疏浚和其他imws可以剥离任何有价值的元素。这些被剥离的元素将被集中在一个矿石区，以备以后回收，而清洁后的残留物也会返回使用，例如作为集料、水泥添加剂或农业改化剂（包括那些通过增强矿物风化来固碳的改化剂）。设计一种真正可持续的方法来实现这一目标是一个非常具有挑战性的问题，这是一种经济上可行的方法，到目前为止，文献中提出的几乎所有浸出废物的过程本身都是碳和化学密集的，因此是不可持续的。我们建议进行研究，其中包括发展“ASPIRE废物储存库”概念的第一步，其中设计了加速成矿“表生”过程的类似物，使休眠废物经历以下过程：(i)将有价值的成分（例如关键金属，磷酸盐）浓缩为人为矿石，以促进其未来的回收；（ii）同时净化残留的矿物材料，使其成为一堆材料，可用于农业、造林、绿化、新发展项目的景观美化、栖息地创造和/或作为水泥/混凝土添加剂或替代骨料。所调查的过程依赖于雨水通过植被表面层，从植物根部和/或其他天然有机物质中释放出天然存在的化合物，然后穿过并从imw中剥离有价值的元素。然后，被动员的元素将进入一个捕获区，在那里它们将从溶液中剥离并浓缩形成人工矿石。该研究项目将寻求设计临时存储废物库的内部流程，以优化这一点。同时，废物储存库的上层植被表面将作为绿色空间，为当地居民提供相应的生态和美化价值。关键的研究挑战之一是如何设计内部ASPIRE废物储存库过程，这些过程依赖于复杂的生物地球化学相互作用和流动行为。另一个重要的研究挑战是发展对利益相关者的理解和对这一概念的更广泛接受，这一概念不符合目前关于废物管理的立法。在英国政府制定向循环经济过渡的战略和支持法规的关键时刻，我们寻求提供一个循环技术解决方案，以便我们如何可持续地管理未来数百万吨的IMMW。

The UK faces serious strategic challenges with the future supply of aggregates, critical minerals and elements. At the same time, the UK must sustainably manage multimillion tonne annual arisings of industrial, mining and mineral wastes (IMMWs). The amount of these wastes generated is projected to increase over the coming years, particularly (i) ash from the combustion of biomass and municipal solid waste, and (ii) contaminated dredgings. These wastes will continue to be landfilled despite often containing valuable resources such as high concentrations of critical metals, soil macronutrients and useful mineral components, some of which actively drawdown atmospheric CO2. The fundamental aim of the ASPIRE (Accelerated Supergene Processes In Repository Engineering) research project is to develop a sustainable method by which ashes, contaminated dredgings and other IMMWs can be stripped of any valuable elements. These stripped elements would then be concentrated in an ore zone for later retrieval and the cleaned residues also returned to use, for example as aggregates, cement additives, or agricultural amendments (including those for carbon sequestration through enhanced mineral weathering). It is a very challenging problem to devise a truly sustainable method to achieve this is an economically viable way, and almost all processes suggested so far in the literature for leaching wastes are themselves carbon and chemical intensive and thus non-sustainable.We are proposing research that comprises the first steps in developing the "ASPIRE waste repository" concept with accelerated analogues of ore-forming "supergene" processes engineered in, such that the dormant waste undergoes processes to (i) concentrate valuable components (e.g. critical metals, phosphate) as an anthropogenic ore to facilitate their future recovery, and (ii) concurrently decontaminate residual mineral material so as to make it available as a bank of material to drawdown for "soft" uses in agriculture, silviculture, greenspace, landscaping in new developments, habitat creation and/or as a cement/concrete additive or replacement aggregate.The processes investigated rely on rainwater passing through a vegetated surface layer which releases naturally occurring compounds from the plant roots and/or other natural organic matter which then pass through and strip valuable elements from the IMMW. The mobilised elements will then pass into a capture zone where they will be stripped from solution and concentrated to form an artificial ore. The research project will seek to engineer the internal processes of the temporary storage waste repository to optimise this. At the same time the upper vegetated surface of the waste repository will serve as greenspace with commensurate ecological and amenity value for local populations.Among the key research challenges is in how to engineer the internal ASPIRE waste repository processes which rely on complex biogeochemical interactions and flow behaviour. Another critical research challenge is to develop an understanding of stakeholder and wider acceptability of this concept which does not fit with current legislation on waste management. With this project we seek to provide a circular technology solution for how we can sustainably manage the future multimillion tonne arisings of IMMW at a critical time as the UK government develops strategies and supporting regulation for the transition to a circular economy.