Designing a circular business model from industrial by-products: A case study on paper mill sludge

The circular economy (CE) emphasises the optimisation of resource yields by keeping products, components and materials at their highest utility and value. This recently popularised concept has created awareness within businesses, government and policymakers. However, there is a discourse that the concept lacks scientific rigour and has primarily been led by practitioners such as policy makers, social scientists and business consultants. Resources in the CE concept are referred to as biological nutrients and technical nutrients. Based on the CE resource recovery model, biological nutrients such as organic waste/by-products are expected to return to the system. However, the current waste management sector is not equipped with how to innovate and/or create value from resources termed as waste/by-products. Whilst CE is a commendable strategy with insightful case studies, the philosophy currently lacks robust design guidance that can provide businesses with the tools and tactics required to meet the agenda. Therefore, this EngD research applies design thinking innovation methodology to an existing business faced with the challenge of adopting a circular business model for resource recovery. The EngD research is based on Ecoganix, an organic waste treatment company. Ecoganix manages Paper Mill Sludge (PMS), a by-product derived from the waste-water treatment of paper mills. In the UK, a million tonnes of PMS is currently produced annually. The management of PMS is an environmental challenge and the second highest cost for the sector after energy consumption. The PMS is collected by Ecoganix from 7 paper mills in the UK for use as soil improvement on farm land . The current management system of PMS is unsustainable and short-term. Moreover, the market is highly competitive due to increasing recycling rates and competitive pricing. Nonetheless, this material PMS is rich in organic cellulose fibres and inorganic minerals. Thus, a design thinking methodology is used to create new value streams of materials from this byproduct...[cont.]