Possible Solutions

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From the course by Universiteit Leiden

A Circular Economy of Metals: Towards a Sustainable Societal Metabolism

13 ratings

Universiteit Leiden

A Circular Economy of Metals: Towards a Sustainable Societal Metabolism

13 ratings

Metals are present everywhere around us and are one of the major materials upon which our economies are built. Economic development is deeply coupled with the use of metals. During the 20th century, the variety of metal applications in society grew rapidly. In addition to mass applications such as steel in buildings and aluminium in planes, more and more different metals are in use for innovative technologies such as the use of the speciality metal indium in LCD screens. A lot of metals will be needed in the future. It will not be easy to provide them. In particular in emerging economies, but also in industrialised countries, the demand for metals is increasing rapidly. Mining and production activities expand, and with that also the environmental consequences of metal production. In this course, we will explore those consequences and we will also explore options to move towards a more sustainable system of metals production and use. We will focus especially on the options to reach a circular economy for metals: keeping metals in use for a very long time, to avoid having to mine new ones. This course is based on the reports of the Global Metals Flows Group of the International Resource Panel that is part of UN Environment. An important aspect that will come back each week, are the UN Sustainable Development Goals, the SDGs. Those are ambitious goals to measure our progress towards a more sustainable world. We will use the SDGs as a touching stone for the assessment of the metals challenge, as well as the solutions we present in this course to solve that challenge.

From the lesson

Solutions to the Metals Challenge

Week 4 is rather packed with lectures on the different options to solve the metals challenge. You will meet experts from all over the world, who will lecture on materials and product design-for-environment and design-for-recycling, on the possibilities and also the barriers for remanufacturing, and on recycling as the last, but maybe most important resort to keep the metals in use. All these options aim at keeping up the stock-in-use of metals in society, while at the same time reducing the need to mine new metals. They all have their own strengths and limitations and can be regarded as pieces of the large puzzle aiming at solving the metals challenge, or in other words, reconciling the different SDGs.

Possible Solutions5:13

Recycling Rates for Metals by Thomas E. Graedel9:04

Materials Design for Recycling by Erik Offerman (Part 1)10:14

Materials Design for Recycling by Erik Offerman (Part 2)12:10

Product Design by Conny Bakker5:27

Remanufacturing15:37

Meet the Instructors

Ester van der Voet
Dr.
Institute of Environmental Sciences

Let's recall the metals challenge as it was explained two weeks ago.

It revolves around two questions:

Do we have access to sufficient metals to fulfill the needs of

the world and are

the environmental impacts related to mental production and use acceptable.

We have seen that for both issues,

we may run into constraints in the future and in some cases already now.

The question for this week is, how can we reduce these challenging issues.

Basically, there are two ways of doing this.

In the first place,

we can take a step by step approach where we look to

the life-cycle of the metals and see how in each step we can make improvements.

This is the topic of this week, Week four,

and we will have lectures on such improvement options from experts in the field.

In the second place,

we can take a more integrated approach, where we look at the metals life-cycle as

a system and see how we can make improvements from that wider system's perspective.

This we will explore next week.

So, let's look at the metals life-cycle,

using the figure of the Yale STAF project we've seen earlier.

We have the mining and refining of metals.

Then we have to production of compound materials and the manufacturing of products.

Then we have to use of these products in households and companies.

And finally, there is a waste management after the products have ended their useful life.

All of these stages are connected to energy use and all of them have waste and emissions.

Over the whole lifecycle,

losses of metals occur and after discarding all the metals are lost anyway,

unless something is done about it.

And there are possibilities to do so over the whole lifecycle.

To start with mining and refining,

the aim of this life-cycle stage is to produce new metals and from our point of view,

this should be done by using as little energy as

possible and create as little waste and emissions as possible.

That means the focus is actually on the processes themselves.

Technological options to increase the efficiency of those processes.

We have seen the process efficiency of mining and refining has improved significantly

over the last century and the end of that is not yet in sight.

The waste streams that are unavoidable should be stored safely.

So they do not contaminate the surrounding environment.

After mine closure, there are possibilities for remediation.

So the site is restored as much as possible.

These options exist, and they are practiced.

Although in many places,

they are not or not yet,

at least so we hope.

In this stage of material production,

a lot of improvements can be made by a more careful material design.

Professor Eric Hofman will go into the possibilities of designing materials

with much less additives which would really improve the possibilities for recycling.

In the stage of product manufacturing,

a design for recycling or designed for the environment can increase

the options we have for repair, remanufacturing, or recycling.

And so keep the materials in use for a longer time.

It's also possible to try and design products using less materials altogether.

Professor Conny Bakker in her lecture will tell

us about the possibilities that exist there.

In the use phase,

the technological options for improvement are limited.

That doesn't mean that nothing can be done.

Consumers are powerful actors in the supply chain.

Their demand drives the supply chain,

and they can take care to keep products in use for a longer time by deciding to

repair instead of throwing the products away or by postponing replacements for some time.

Technological options to keep the material and products

in use for a longer time do exist.

Repair, refurbishing and remanufacturing do just that.

Professor Nabil Nasr a well-known expert on

remanufacturing will tell us about these options.

Finally, there is a waste management.

The main option here,

at least for metals,

is to recycle them instead of throwing them away.

Professor Thomas Graedel talks about recycling.

So, this is a full week.

But we are lucky to have experts from all over the world to inform us.

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