The word waste is normally referred to as something which can be re-cycled, re-used, reduced or even eliminated. The concept of Zero Waste is being constantly worked on, while the focus has been on waste elimination with the approach of recycling and reusing waste products. This gives relevance to the term Zero Landfill where waste is overall reduced or eliminated resulting in removal or reduction of landfills.
The term Zero Waste is constantly encouraging both producers and consumers to adopt sustainable approaches to reduce their expenditures as well as make the world a better place. In the past researchers have highlighted numerous techniques to tackle physical waste, however the chemicals which are normally generated from this waste is more critical and limitedly reported.
Zero Waste works because the end goal is to have the waste generated reused, repurposed, recycled and even resold. It is the guiding principle for all manufacturers to strive for zero waste and it is this initiative that is driving the manufacturing industry to become greener andderive more cost efficiency. By embracing zero waste as a concept, industry leaders are improving their resource management and making progress towards significant waste reductions.Waste reduction is not just about “being green” – it’s about achieving cost efficiency and cost reduction techniques that has proven over time as being worthwhile investment. At the base level, the more waste one produces, the more waste one needs to ship out or process and that means more frequent pay-outs for waste management.Added to this the Zero Landfill means that there is no payment for shipping waste to a landfill.
Having said all of this, how do we implement a zero-waste model? Let us take a closer look. One of the most pertinent way to start a zero-waste model is to start incorporating the basic building blocks of sustainability.
Zero Waste Manufacturing (ZWM) is believed to be a roadmap for the future of manufacturing by which the burning issue of ‘waste’ can be tackled. It can be supported with recycling and reusability of the produced wastes in another manufacturing process, use of optimization tools and sustainable manufacturing theories, development of precision manufacturing ideas applied in the prominent sectors with an aim to either re-cycle/re-use the discarded ones or to produce a fresh part in the eco-friendly manner. Special attention needs to be paid to the current trends in manufacturing.
Until now Zero Waste Manufacturing (ZWM) has been a conceptual term that encourages the manufacturing systems to produce parts/needs without contributing towards waste. As per the availability of manufacturing tools and systems within the small scale, medium scale and even large-scale industries, it is practically impossible to eliminatethe waste associated with it. However, it is possible to move towards Zero Waste Manufacturing (ZWM) through recycling, redesigning, and reusing the waste produced from one process to another process. As material, energy and waste costs rise, environmental efficiency improvements will have grater benefit than ever before. Further sustainable material flow will improve and become more mainstay in the manufacturing processes.
Manufacturing plays a prominent role in waste generation and could be resolved by adopting methodologies, systems and processes in which the product once produced can fulfil multi-utility even after it gets obsolete from primary application. To achieve this significant attention must be given to manufacturing to create products that can be easily reused and achieve consistent function with a reliable service life across multiple use cycles. Manufacturing presents a challenge in achieving sustainable flow cycles as the attitude towards conventional manufacturing processes is one of the major barriers. To tackle such barriers, various countries have started collaborative research projects within their academic institutions and industries.
Singapore’s Research Innovation and Enterprise plan, known as RIE2020 is one such example of a major thrust in Advanced Manufacturing and Engineering (AME). Other examples in Asia include initiatives like Make in India, China Manufacturing 2025, Digital Korea and Japan’s Industrial Value Chain Initiative. Initiatives like Factories of the Future in Germany and Innovative Manufacturing in UK are good examples in Europe. In the US there is the US Advanced Manufacturing Initiative program.
The three most emerging and popular themes in manufacturing are: 1) Digital Manufacturing (DM) 2) Sustainable Manufacturing (SM) and 3) Zero Waste Manufacturing (ZWM).
Digital Manufacturing leverages advances in digital technologies to model, design, simulate and analyse machines, tooling and input materials to optimise the manufacturing processes and produce customised products for specific markets. Besides the benefits of Digital Manufacturing (DM) include improved productivity, resources efficiency and customized mass production. Resource Efficiency entails optimal utilization of materials, energy and water in the manufacturing process thus eliminating pollution and reducing costs. It also leads to the aspiration of the concept of Zero Waste Manufacturing (ZWM) which involves designing of products and processes in which no waste is sent to landfills or incinerators. Wider scope of this would eliminating all emissions during manufacturing to land, water or air that are a threat to the planetary, human, animal or plant health. One of the approaches adopted is to redesign products and materials selection suitable for reuse. Another approach is to conserve and recover resources from the used products and use them in manufacturing new products. Some of the recent innovation towards re-cycling and reusability of the waste in the manufacturing applications, focus on various Sustainable Manufacturing (SM) processes.
Zero Waste is a whole system approach having aims to eliminate rather than manage waste. Zero emissions or effluent processes represents a shift from the traditional industrial practices wherein wastes from one system acts as input material for another. It advocates an industrial formation that can minimize its impact on the natural resources. Zero-Waste can be categorized into the following sub-systems: a) Zero Waste in Administration and Manufacturing b) Zero Waste of Resources c) Zero Emissions d) Zero Waste in Product Life and e) Zero Use of Toxins. It should be further highlighted that waste cannot be responsibly dumped without the concern and preparation because not only is it unsightly, unhygienic and potentially disastrous to the environment, it also required the allocation of space and incurs costs related to the consequences of the waste disposal. Suitable landfill sites are becoming more difficult to find and there is large cost involved in providing conveniently located and environmentally responsible landfill facilities.
Waste can be significantly controlled and treated either through re-use or re-cycle. However, both these two terms are confused with each other. Let us take an example to understand what we mean by re-use. Suppose there is an obsolete computer whose parts are the hard disk, screen, graphic cards, cabinet etc. which may be used. This would constitute re-use. Whereas re-cycle involves re-processing may be thermally, chemically or mechanically, of the materials not in the system through material recovery and synthesis operations. Re-cycling approaches applied in different types of waste materials through suitable engineering applications is also an important aspect.
One of the good examples is Plastic as a material with its countless applications. It is impossible to conceive of a modern civilization without the use of plastics. They are used in household appliances, greenhouses, mulches, coating & wiring, packaging, construction, medicine, electronics, automotive and aerospace components, to name just a few. Various types of plastics produced throughout the world can be classified as follows: Polyethylene (PE), Polyvinyl Chloride (PVC), Thermoset, Polypropylene (PP) and Polystyrene (PS) respectively. Apart from this there are plastics types like Acrylonitrile Butadiene Styrene (ABS), Polyamide (PA) or Nylon-6, Polylactic Acid, etc. Thermoplastics are used in the typical plastic applications like packaging as well as non-plastic applications like textile fibres and coatings. Apart from this, plastic in various forms and types are found in all major solid waste categories including containers and packaging plastics such as sacks, wraps, soft drink, milk bags and water containers. In durables goods plastic is found in Appliances, furniture, casings of lead-acid batteries and other products.
With all these it is evident that if there is a focused attempt in re-cycling and re-using of plastic, it can make a significant thrust to Zero Waste Manufacturing as well drive towards overall Zero Waste. The several options available to treat, re-use and re-cycle plastic include re-extrusion (primary process), mechanical re-cycling (secondary process), chemical re-cycling (tertiary process) and energy recovery (quaternary process). Re-use of plastic is most economic and easy, though it demands time, funds and innovations toobtain proper utilization of waste plastics for certain applications. On the other side re-extrusion re-cycling involves the re-introduction of clean scrap of single polymer to the extrusion cycle to produce products of similar material. This process utilizes scrap plastics that have similar features to the original products. Currently most of the plastic wastes are being recycled with the help of this technique. Zero Waste is a goal that is ethical, economical, efficient and visionary, to guide people in changing their lifestyles and practices to emulate sustainable natural cycles, where all discarded materials are designed to become resources for others to use.
