A viability study into shallow water offshore mining, with a focus on mineral processing techniques

Abstract

Rationale - Increasing world population and consumption, and rising dependency on certain countries for the supply of raw materials lead to the demand for new raw material resources. This demand, combined with the increase in complexity of new land-based mining operations increases the chances for a viable offshore mining business case. Goal and scope - The aim of this research is twofold. The first aim is to fill knowledge gaps in the offshore mining value chain, with a focus on the processing of the mined material. The second goal is to assess if shallow water offshore mining is a viable business option. Explicitly left out of scope are the exploration for mineral deposits as well as the detailed or new design of an extraction method for subsea minerals. Furthermore, resources beyond the continental plate are not part of this research. Approach - To answer the first goal of this research, an extensive literature study is performed comprising an assessment of potential offshore mineable minerals and their respective markets. It also included an analysis of current land-based mineral processing techniques and its limitations in an offshore environment. Furthermore environmental, legislative and tax aspects were included as well as detailed descriptions of future offshore mining projects, and current dredge mining projects. To assess the viability of an offshore mining project, a case study is set-up of a prospective offshore mining project. A method for executing the case study is developed. Results of the case study - For the case study the mineral deposit has been studied and based on its mineral characteristics a location specific processing flow sheet is developed. The case study resulted in a set of execution alternatives, from which a preferred option was selected. Based on this option the viability of the project is assessed with the use of a discounted cash flow method (DCF-method). Conclusions - Main knowledge gaps are identified as the impact on the environment, and the lack of legislation regarding offshore mining. Furthermore, it should be noted, that the public opinion regarding offshore mining is important to consider as well.