Resource Recovery from Wastes

Towards a Circular Economy

Lynne E Macaskie, Devin J Sapsford, Will M Mayes, Lynne E Macaskie, Devin J Sapsford, Will M Mayes

• Publisher: Royal Society of Chemistry
• Year: 2019
• Print ISBN:
  9781788013819
• eBook ISBN:
  9781788018654
• Edition: 1
• Topic: Tecnologia e ingegneria
• Subtopic: Scienze ambientali

The concept of a circular economy has been gaining increasing attention in recent years. Many of the sources of chemicals we have become reliant on are dwindling and the accumulation of waste products poses a serious environmental problem. By recovering resources from these waste materials, we can reduce our dependence on virgin feedstocks that may not be sustainable as well as reducing the quantity of material going to landfill sites.

Incorporating different perspectives from a global authorship, this book aims to introduce systems thinking to the field of waste and resource management. The topics covered range from the use of biogeochemical processes in resource recovery to the application of engineered nanomaterials, with information relevant to both academia and industry.

The broad range and cross-disciplinary nature of the topics in this book make it a valuable resource for those working in circular economy research, green chemistry and waste and resource management.

Section 1

General Introduction

CHAPTER 1

A New Perspective on a Global Circular Economy

A. P. M. VELENTURF,*^a P. PURNELL,^a L. E. MACASKIE,^b W. M. MAYES^c AND D. J. SAPSFORD^d

^a School of Civil Engineering, University of Leeds, Leeds, UK; ^b School of Biosciences, University of Birmingham, Birmingham, UK; ^c Department of Geography, Geology and Environment, University of Hull, Hull, UK; ^d School of Engineering, Cardiff University, Cardiff, UK

*Email: [email protected]

1.1 The Importance of a Global Circular Economy

Natural resource exploitation is accelerating in the face of resource decline, while at the same time people are generating ever growing fluxes of wastes and pollutants.^1–3 Global resource use has grown from 23.7 billion tonnes in 1970 up to 70.1 billion tonnes in 2010, and simultaneously the global population has nearly doubled and the economy more than tripled.¹ Per capita global material use increased from 7 tonnes in 1970 to 10 tonnes in 2010, indicating improvements in living standards in many countries. However, globally an estimated 11.2 billion tonnes of municipal waste was collected in 2010, roughly 2 tonnes for every person on the planet, and a similar amount of uncollected waste is anticipated to have been generated.⁴ Current global consumption levels and the associated over-reliance on waste disposal and emissions rather than reuse and recycling are unustainable. The ecological ceiling of planetary boundaries has been crossed and humanity is risking destabilisation of the geological conditions upon which our society depends.^5,6 Nevertheless, the growing resource use has, for many people, strengthened social foundations, incomes and welfare. The long term well-being of people does however depend on a healthy environment, providing the resources that are necessary to meet basic human needs including access to clean water, food and shelter.⁷ However, resource extraction and waste production have now reached such a scale that they result in unprecedented environmental degradation, climate change and pollution – thereby violating basic human rights and needs.^1,8,9 The boundaries to sustain long-term environmental and socio-economic stability have been crossed. Radical changes in the ways in which waste and resource flows are organised, i.e. the resource economy, are necessary.¹⁰

Minimisation of resource use and increased resource efficiency are necessary to limit the throughput of materials in the economy.¹ Concepts such as zero waste, waste hierarchy and sharing economy are gaining ground and can be captured under the umbrella of ‘circular economy’ (Table 1.1). Given the diversity in conceptual roots it is unsurprising that circular economy has been described in more than a hundred ways.^11,12 These diverse concepts all refer to making better use of resources,¹¹ here introduced by the words of the Ellen MacArthur Foundation¹³: “Looking beyond the current ‘take, make and dispose’ extractive industrial model, the circular economy is restorative and regenerative by design. Relying on system-wide innovation, it aims to redefine products and services to design waste out, while minimising negative impacts. Underpinned by a transition to renewable energy sources, the circular model builds economic, natural and social capital.” Circular supply chains that minimise wastes and strive to reuse, repair and recycle where wastes cannot be prevented need to be more sustainable than the linear systems they replace (Table 1.1); the ability of circular economy to contribute to sustainable development has been broadly accepted yet requires further conceptual development supported by empirical evidence.¹⁴ Most production-consumption systems cannot circulate 100% of resources, for example due to quality losses and energy requirements, and hence new resource inputs from the natural environment will remain necessary even in a circular economy. Moreover, a transition towards a circular economy requires innovative technologies and business models as well as cultural change. It will take time to move away from our current linear and economic growth centred systems to more circular systems that promote a healthy environment and greater equality. In the transition phase, a circular economy needs to be realised that enables business development through greater resource efficiency and contributes positively to the environment and society by maintaining the technical value, i.e. the functional qualities¹⁵ of materials that circulate through the production-consumption system.¹⁶

Table 1.1Key terminology.

Key terminology	Description
Bioeconomy	“The bioeconomy comprises those parts of the economy that use renewable biological resources from land and sea – such as crops, forests, fish, animals and micro-organisms – to produce food, materials and energy”.^17
Biogeochemical process	Transformations of inorganic and organic elements and compounds in the lithosphere, hydrosphere and atmosphere that are mediated, directly or indirectly, by biological (chiefly microbiological) entities.^18
Circular economy	“Circular economy systems keep the added value in products for as long as possible and eliminate waste. They keep resources within the economy when a product has reached the end of its life, so that they can be productively used again and again and hence create further value”.^19
Cradle to cradle – technical and biological flows	A design approach that seeks to regenerate natural systems through the integration of flows of materials in society (technical flows) with those in the environment (biological flows).^20
Ecosystem services	The services provided by ecosystems to the benefit of people. Four types of ecosystem services have been defined: provisioning services (e.g. food, water); supporting services (e.g. soil formation, nutrient cycling); regulating services (e.g. climate, water quality); and cultural services (e.g. recreation, aesthetics).^7 It is increasingly common for economic values to be associated with each service, based on e.g. the social costs avoided, or the replacement costs should such services be supplied by engineered systems.
Ecosystem stewardship	People are an integral part of the ecosystem and carry a responsibility to manage the environment such that resource use is compatible with the capacity of ecosystems to sustain services.^7
Linear economy	An economy dominated by behaviour in which materials are extracted from the biophysical environment, fashioned into products using non-renewable energy sources, and disposed of after use as a waste without any form of recovery.
Multi-dimensional value	A combination of economic (e.g. monetary price or worth of a resource), social (e.g. contribution to quality of life), technical (e.g. functional characteristics of a material or product) and environmental (e.g. contribution to biodiversity) values that each may be positive (benefits) or negative (costs). These must be considered holistically e.g. by using recognised multi-criteria decision analysis tools.^15
Natural and Industrial materials	Natural materials located in a biophysical environment that is not directly controlled by people; it may be of natural or engineered origin and participate in naturally occurring geological, chemical and biological processes without causing environmental harm. Industrial materials are resources transformed in the production-consumption system and ideally would be engineered in a way that enables reintegration into natural processes without negative environmental consequences upon return into the uncontrolled biophysical environment but may not be able to participate safely in such processes without remedial treatment.^21
Natural capital	“The world's stocks of natural assets which include geology, soil, air, water and all living things” providing ecosystem services.^22
Planetary boundary	Outline of the ‘safe operating space’ for humanity in different aspects of the earth system. Crossing these boundaries could cause catastrophic environmental change, destabilising global ecosystems into states that are less desirable for people.^5
Production-consumption system	The industrial system of production and use of materials and products as well as services, from resource extraction throughout the life-cycles of materials and products and, ultimately, disposal and possible return to the biophysical environmental (Figure 1.2).
Sustainable development	Sustainable development is most commonly defined as “development that meets the needs of the present without compromising the ability of future generations to meet their own needs”.^23
Sustainable development goals	The 17 global goals in the United Nations’ 2030 Agenda For Sustainable Development.^24
Waste and by-product valorisation	The process of reusing, recycling or reprocessing to gain value from a waste, by-product or its constituents.
Waste hierarchy	A tool to promote better resource use by prioritising waste prevention, followed by reuse, recycling, other recovery and disposal.^25

1.2 Visualising the Circular Economy

The circular economy is depicted with the widely referenced butterfly diagram (Figure 1.1) that was developed by Braungart and McDonough²⁰ for the Ellen MacArthur Foundation.²⁶ The diagram shows separate ‘biological’ and ‘technical’ materials flows. ‘Technical’ materials are finite and are used in a closed loop system through sharing, maintaining, reusing, remanufacturing, and recycling of products. Conversely, ‘biological’ materials are renewable and organised in an open loop system of resources cascading through subsequent steps of extraction, production of bio-based materials, energy recovery, and returning nutrients to the biosphere to feed the next production cycle of primary crops. The Ellen MacArthur Foundation has catalysed a global movement towards circular economy, inspiring governments and companies around...

Table of contents

• Cover
• Title
• Copyright
• Foreword
• Contents
• Section 1: General Introduction
• Section 2: Organic Waste Materials Upconversion
• Section 3: Metallic Waste Materials Upconversion
• Section 4: Circular Economy and Governance
• Subject Index