In Practice: how automation is revolutionising waste

Writing for Environment Journal, Dr Benjamin Eule of Stadler Engineering explains how equipment automation is driving the future of waste management.

It’s difficult to comment on recycling automation without predicting the impact this will have on the 70,000+ people employed within the industry. A recent report from PricewaterhouseCoopers (PwC) claimed that as many as 30% of existing job roles in the UK could be automated by 2030, with the waste management sector among the most at-risk sectors. It suggested that jobs in waste management face a 62.6% chance of being automated, the highest number of job roles to be lost among a wave of automation.

There’s no doubt that recycling facilities are increasingly looking towards technology to improve throughputs and drive operational efficiency. Through next-generation technology, productivity and fraction quality can be maximised, while minimising costs and reducing contamination. Advances in digitisation and artificial intelligence, largely in the form of automation, is seen as an effective way of driving the sector forward. But how much is the global recycling industry embracing automation and what can be done to accelerate the process?

Automation is already optimising recycling to fulfil the requirements of high volumes, low environmental impact and economic profitability. Back in 2014, Stadler worked on a project to design, build and commission the world’s first fully-automated waste sorting plant in Oslo, Norway. Built in just three months, the facility comprises 14 near infra-red (NIR) units and can process up to 30 tonnes of waste per hour. Four years ago, it was seen as a major milestone for the global recycling industry, even winning an award for innovation. Fast forward the clock four years and it is often assumed that few plants in Europe are built to match this level.

Little could be further from the truth. In fact, up to 50% of Europe’s recycling plants now feature automated processes. From eddy current separators that utilise a powerful magnetic field (separating non-ferrous metals from waste), to electromagnets used to recover tins and cans, automation in isolation is a common theme of most modern MRFs.

But the productivity gains that can be made from automation lie not in a complete overhaul of equipment, but in the intelligent integration of technology.

Take our plant in Oslo as an example. Both a municipal solid waste recycling and anaerobic digestion facility, it was based upon a three-container system. The first is a specially designated green bag for food waste, plastic and residual waste; the second container is for paper and cardboard, and the third is for glass and metal packaging. While the plant features well-known technology, Stadler delivered systems integration in a unique way, according to the individual requirements of the customer.

Besides the automatic separation of green bags from the waste stream for AD, the predominant objective was the separation of recyclable materials including polymers, paper, metals, wood and refuse-derived fuel (RDF) from all waste streams. The automated separation of organic waste in green bags ensures the rest of the waste and recyclable materials are not contaminated.

The Oslo project set a precedent for a wider industry move towards custom-made modular solutions, embedded with automation and intelligence. Modularisation offers a host of benefits, particularly the ability to scale-up MRFs on demand, rather than having to commit to a long-term infrastructure investment. Furthermore, by automating individual processes at a time, MRFs can take a longer-term approach, analysing and streamlining bottlenecks one stage at a time in their drive towards greater efficiency.

The benefits of a fully automated, modular MRF are widely understood; improved productivity, better quality recyclate and greater flexibility to grow. But what of manual intervention? Are we heading towards an MRF that operates independently of human instruction in our attempt to meet challenging recycling targets?

The quick answer is no. Although manual intervention is being minimised through MRF automation, it is far from replacing the need for skilled workers. Indeed, there are some areas of the recycling process that are a long way from automation.

For example, municipal solid waste destined for incineration must be manually pre-sorted to remove any oversized materials and recover valuable fractions such as plastic. Cutting-edge equipment, such as optical sorters, can be deployed later down the chain, but this is largely to complement, rather than replace manual efforts. It is still very difficult to replicate the accuracy of the human eye of experienced workers.

The opportunity for MRFs is to stimulate further job growth in a digitised waste society and, indeed, PwC believes that jobs in the waste sector will not become obsolete, but rather they will evolve to support the integration of technologies. New opportunities exist for remote monitoring, MRF performance analysis and equipment maintenance, attracting a new generation of professional to this fast-growing industry.

Dr Benjamin Eule is a director at Stadler Engineering