Using the Pugh Method to Select a Polymetallic Nodule Vertical Transport System

Abstract

On the sea floor of specific deep ocean environments lie prolific amounts of polymetallic nodules that contain minerals critical to meeting the future energy demands of a growing worldwide population. Polymetallic nodules rich in manganese, nickel, and cobalt spread over millions of square kilometers of abyssal seabed and contain the minerals needed for future energy storage demands. The offshore oil and gas industry seeks to participate in the energy expansion by leveraging its deepwater experience to harvest these nodules. The knowledge and wisdom gained from decades of operating offshore provides significant insight into the development and implementation of the technology needed to address the challenges of deep sea nodule harvesting. The authors describe a design selection tool based on the methods described by Stuart Pugh to select a polymetallic nodule Vertical Transport System. Stuart Pugh, known for his work in product design and development, introduced the Pugh Method in the 1980s. The Pugh Method is a structured and integrated process applied to design development including concept generation, evaluation, and selection. The Vertical Transport System design processes uses the Pugh Method to recommend a candidate design. The evaluation step uses a two groups of company experts who present the concepts (the team), and collectively evaluate (the group) and recommend the best design concept for further development. We apply the method to the case of deep sea mineral recovery operations specifically the design of the Vertical Transportation System. First, the authors introduce the Pugh Method tool, how it works, and how it applies to this specific case. We describe how risks and rewards relate to each selection characteristic used to evaluate the Vertical Transport System concepts. Further, we talk about team selection and the points to consider when assembling the right team to achieve credible results. Next, we describe each concept identifying and recognizing the various technical, operational, and economic selection characteristics, such as size, power consumption, reliability, availability, etc. Finally, we evaluate each concept against the different selection characteristics and discuss the results. The paper concludes with a robust process flow chart describing the selection method for a Vertical Transport System.