Publications
-
Abstract
Resource efficiency is one of the greatest challenges for sustainable manufacturing. Material flow in manufacturing systems directly influences resource efficiency, financial cost and environmental impact. A framework for material flow assessment in manufacturing systems (MFAM) was applied to a complex multi-product manufacturing case study. This supported the identification of options to alter material flow through changes to the product assembly design, to improve overall resource efficiency through eliminating resource intensive changeovers. Alternative assembly designs were examined using a combination of intelligent computation techniques: k-means clustering, genetic algorithm and ant colony algorithm. This provided recommendations balancing improvement potential with extent of process modification impact.
SMART authors: James Colwill , Alessandro Simeone
-
Abstract
Resource efficiency is recognized as one of the greatest sustainability challenges facing the manufacturing industry in the future. Materials are a resource of primary importance, making a significant contribution to the economic costs and environmental impacts of production. During the manufacturing phase the majority of resource efficiency initiatives and management methodologies have been concerned primarily with improvements measured on an economic basis. More recently, the need for even greater levels of resource efficiency has extended the scope of these initiatives to consider complete manufacturing and industrial systems at an economic and environmental level. The flow of materials at each system level relates directly to material efficiency, which in turn influences the consumption of other resources such as water and energy. Initial research by the authors in material efficiency focused on material flow, proposing a material flow assessment approach, comprising a systematic framework for the analysis of quantitative and qualitative flow in manufacturing systems. The framework was designed to provide greater understanding of material flow through identification of strengths, weaknesses, constraints and opportunities for improvement, facilitating the implementation of improvement measures for greater efficiency in both environmental and economic terms. This paper presents an extension of this work, applying the material flow assessment framework to a complex multi-product and multi-site manufacturing system scenario. It begins with a description of the Resource Efficient Scheduling (RES) tool that supports the implementation of this framework. The tool models the interactions of quantitative and qualitative material flow factors associated with production planning and the resulting impacts on resource efficiency. This provides a more detailed understanding of the economic and resource impacts of different production plans, enabling greater flexibility and the ability to make better informed decisions. Finally a case study is presented, highlighting the application of the tool and its potential benefits.
SMART authors: Shahin Rahimifard , James Colwill , Alessandro Simeone , Oliver Gould
-
-
Abstract
As resources become scarcer, efficiency improvements alone will not bridge the widening gap between supply and demand, resulting in the need for additional non-financial mechanisms to ensure the fairer allocation of resources. This paper asserts that, in the future, companies will need to demonstrate their products’ positive contribution to society as well as minimising their negative environmental/social impacts. A review and analysis of existing tools and assessment methodologies identifies current capabilities and highlights the need for 'Societal Value’ assessment that considers both quantitative and qualitative factors .This paper concludes by proposing a systematic framework for addressing the 'Societal Value’ of products as part of an integrated sustainability assessment and allows the evaluation and comparison beyond products’ shared functionality.
SMART authors: James Colwill , Kei Lok Felix Shin
-
Abstract
Improving material efficiency is widely accepted as one of the key challenges facing manufacturers in the future. Increasing material consumption is having detrimental impacts on the environment as a result of their extraction, processing and disposal. It is clear that radical improvements in material efficiency are required to avoid further environmental damage and sustain the manufacturing sector. Current resource management approaches are predominantly used to improve material consumption solely in economic terms. Meanwhile, environmental assessment methodologies can determine sources of significant environmental impact related to a product; however, a methodology to effectively assess material efficiency in production systems is currently not available. This paper highlights the benefits of material flow modelling within manufacturing systems to support advances in increased material efficiency, proposing a framework for ‘material flow assessment in manufacturing’ that promotes greater understanding of material flow and flexibility to explore innovative options for improvement.
SMART authors: James Colwill , Oliver Gould
-
Abstract
Sustainability encompasses three elements; economic, social and environmental. Sustainable development aims to reduce impacts of all three elements. Currently, there are a number of tools for assessing products’ sustainable impact and improving their performances. Life cycle assessment (LCA) is one of the more commonly used tools for such purpose. LCA is used for assessing environmental impacts associated with all the phases of a product's life from cradle-to-grave (raw material extraction, manufacturing, distribution, use, and end-of-life). Similar tools were developed to assess economic and social impacts, such as life cycle costing (LCC) and Social-LCA (S-LCA).
However, these tools compare products on the basis of shared functionality (A functional Unit), for example when comparing a pen and a pencil a functional unit that prescribes ‘the drawing of a line 20km in length’, will have to ignore other non-shared functions such as permanence, fragility, etc. As the corresponding shared functionality decreases, so the validity of any comparison becomes weaker, such as the comparison between a horse and a car as a mode of transport. Furthermore, while sustainability improvements can be achieved using these tools; they are generally limited to reducing the negative impacts and optimising efficiencies at each stage of the life cycle and ignore the potential benefits of increased functionality and positive benefits.
This paper proposes that a fairer and more accurate assessment of a product would include its positive impacts ‘value’ at an individual and societal level. Furthermore, consider the ‘value’ of a product as well as its environmental, social and economic impacts would provide a much fairer basis on which to allocate resources in a resource constrained future where difficult decisions will inevitably have to be made.
This research has particular relevance in supporting strategic planning decisions aimed at increasing future resilience in manufacturing companies. At present, sustainable assessing tools offer little or none in value assessment, particularly during the use phase of products. The research presented in this paper indicates that the measurement and assessment of these positive benefits will be a key decision factor in a resource critical future, where decisions will be made based on the inherent value of products, providing a more socially equitable and responsible way of distributing resources. This paper reports specifically on the addition of this value consideration in product assessment within the UK toy industry, however it is clear that these findings have a broader significance across all manufacturing industries and geographic regions.
SMART authors: James Colwill , Kei Lok Felix Shin
-
Abstract
As global demand for petrochemical products increases and competes for finite oil resources currently exploited as an energy source, the need for the energy mix to include renewable generation is ever more acute. Naturally abundant solar, wind, geothermal and tidal energy can be used to generate electricity using renewable technologies; however, a major barrier to this is the availability of materials required to manufacture. One group of metals, commonly known as Rare Earth Elements (REE) are frequently contained as functional materials in renewable technologies including solar cells. A reliable and sustainable supply of REE is therefore critical for renewable energy generation.
REE comprise seventeen chemical elements, the fifteen lanthanides plus scandium and yttrium. Despite their name, rare earth elements are abundant in the Earth's crust; however, REE are typically widely dispersed and found in low concentrations that are not economically exploitable. Global demand for REE is increasing exponentially due to their use in a plethora of consumables and industrial applications together with increasing demand from rapidly industrialising countries. Current uses for REE include: permanent magnets, batteries, catalysts, computer memory and lighting to name but a fraction. Global supply of REE originates from very few countries, mainly China, who provide over 90% of the global supply and have recently implemented export restrictions including quotas and taxes. Many factors currently limit the supply of REE. Environmentally damaging extraction processes combined with competition for land-use mean that there are many restrictions on mining operations around the world. As relatively high-grade deposits become exhausted and lower-grade deposits are exploited, the energy demand for extraction increases. Sometimes REE are deposited as trace elements within other commercially extracted minerals; here the REE are a commercial by-product of the primary ore extraction. Therefore, the supply of REE extracted in this manner fluctuates depending upon extraction of the primary ore. Long lead-times to set up new mining operations mean that increased REE demand cannot be quickly met, leading to a significant time-lag between variation in demand and the reaction of supply. Global demand is growing but supplies are not guaranteed therefore prices are rising sharply and will continue do so. There is rarely a simple substitution of REE for another material. Less than 1% of REE are currently recycled. Recycling REE reduces consumption of energy, chemicals and reduces emissions in the primary processing chain. Most recycling processes have a high net-benefit concerning air emissions, groundwater protection, acidification, eutrophication and climate protection. A more efficient option than recycling is the remanufacture of components and products that contain REE. This research investigates the current and future use of REE and their application in technologies such as renewable energies. The aim is to facilitate a sustainable supply of REE for manufacturers through the use of strategies such as the reuse, refurbishment, remanufacture and recycling of components and materials.
SMART authors: James Colwill , Liam Gardner
-
Abstract
There is a growing body of evidence which increasingly points to serious and irreversible ecological consequences if current unsustainable manufacturing practices ad consumption patterns continue. Recent years have seen a rising awareness leading to the generation of both national and international regulations, resulting in modest improvements in manufacturing practices. These incremental changes however are not making the necessary progress toward eliminating or even reversing the environmental impacts of global industry. Therefore, a fundamental research question is `how can future of manufacturing industry` A common approach adopted in such cases is to utilize exercises to develop a number of alternative future scenarios to aid with long-term strategic planning. This paper presents the results of one such study to create a set of `SMART Manufacturing Scenarios` for 2050.
SMART authors: Shahin Rahimifard , James Colwill , Leila Sheldrick
-
Abstract
The use of renewable materials has attracted interest from a wide range of manufacturing industries looking to reduce their environmental and carbon footprints. As such, the development and use of biopolymers has been largely driven by their perceived environmental benefits over conventional polymers. However, often these environmental claims, when challenged, are lacking in substance. One reason for this is the lack of quality data for all life cycle stages. This applies to the manufacturing stages of packaging, otherwise known as ‘packaging conversion’, where for certain product/production types, a reduction in energy consumption of 25–30% from lower processing temperatures can be offset by an increase in pressure, cycle times and reject rates. The ambiguity of the overall environmental benefit achieved during this stage of the life cycle, when this is the main driver for their use, highlights the need for a clearer understanding of impact that such materials have on the manufacturing processes.
SMART authors: Shahin Rahimifard , James Colwill
-
Abstract
Recent trends in the bio-plastics industry indicate a rapid shift towards the use of bio-derived conventional plastics such as polyethylene (bio-PE). Whereas historically a significant driver for bio-plastics development has been their biodegradability, the adoption of plastics such as bio-PE is driven by the renewability of the raw materials from which they are produced. The production of these renewable resources requires the use of agricultural land, which is limited in its availability. Land is also an essential requirement for food production and is becoming increasingly important for fuel production. The research presented in this paper envisages a situation, in the year 2050, where all plastics and liquid fuels are produced from renewable resources. Through the development of different consumption and productivity scenarios, projected using current and historic data, the feasibility of meeting global demands for food, liquid fuels and plastics is investigated, based on total agricultural land availability. A range of results, comparing low-to-high consumption with low-to-high productivity, are reported. However, it is from the analysis of the mid-point scenario combinations, where consumption and productivity are both moderate, that the most significant conclusions can be drawn. It is clear that while bio-plastics offer attractive opportunities for the use of renewable materials, development activities to 2050 should continue to focus on the search for alternative feed stocks that do not compete with food production, and should prioritise the efficient use of materials through good design and effective end-of-life management.
SMART authors: Shahin Rahimifard , James Colwill
-
Abstract
The growing interest in bio-polymers as a packaging material, particularly from companies looking to reduce their environmental footprint, has resulted in wider adoption. Traditionally the selection and specicification of packaging materials was based on aesthetic, technical and financial factors, for which established metrics exist.
However with bio-polymers, where the primary rationale for their use is environmental, alternative metrics are required. Furthermoe, there is a significant stratgeic element to the decision process that requires a broader range of horizontal and vertical inputs, both within the business and the wider supply chain. It is therefore essential that a holistic approach is taken to the bio-polymer based packaging design process to ensure that the final packaging meets the original strategic intent and overall requirements of the business. Current ecopackaging design tools are generally limited to professional users, such as designers or packing engineers, and generally provide tactical rather than strategic support. This disconnect, between the need for inclusivity and greater strategic support in holistic design, and the exclusivity and largely tactical support of current eco-design support tools, indicates a clear need for a new decision support tool for sustainable pack design using bio-polymers.
This paper proposes a framework for an eco-design decision support tool for bio-polymer based packaging that has been developed using a predominantly qualitative research approach based on reviews, interviews and industrial packaging design experience and is an extension of previously published work. This research investigatesfurther how existing eco-design methods, such as the 'Balanced score card', can be applied within the tool and how the shortcomings associated with incorporating social and environmental aspects can be partly resolved, through a simplified set of metrics tailored specifically for bio-polymer packaging decisions. The results of this research is a framework for the development of a three tier eco-design tool for bio-polymer packaging that provides decision support at the three critical stages of the design process: stratgic fit, Feasbility assessment and concept/pack development.
SMART authors: Shahin Rahimifard , James Colwill
-
Abstract
Bioplastics derived from renewable polymers such as sugars, starches and cellulose, have attracted significant interest from companies looking to reduce their environmental footprint. New production capacity and improved materials have resulted in their increasing adoption for mainstream consumer products packaging. However questions remain regarding their overall environmental benefits and how the maximum environmental gain can be achieved. These uncertainties highlight the need for a decision support tool to aid the packaging design process. This paper examines the issues surrounding bio-derived polymer use and discusses the development of an eco-design tool to assist in their rapid and efficient adoption.
SMART authors: Shahin Rahimifard , James Colwill
-
Abstract
Oil-derived plastics have become well established as a packaging material over the past 75 years due to their many technical and commercial advantages. However, the disposal of plastic packaging waste, a large proportion of which still goes to landfill, continues to raise increasing environmental concerns. Meanwhile, the price of oil continues to rise as demand outstrips supply. In response, biodegradable polymers made from renewable resources have risen to greater prominence, with a variety of materials currently being developed from plant starch, cellulose, sugars and proteins. Whilst the polymer science continues apace, the real ecological impacts and benefits of these materials remain uncertain. Although life cycle assessment (LCA) has been used to provide comparisons with oil-derived plastics, published studies are often limited in scope, allowing the validity of their conclusions to be challenged. The literature appears to support the popular assumption that the end-of-life management of these materials requires little consideration, since their biodegradable properties provide inherent ecological benefits. Opportunities for conserving resources through the recycling of biopolymers are rarely addressed. Through a review of current academic, industrial and commercial progress in the field of biopolymers, a number of LCA case studies are proposed which will address this weakness in existing research, related to the recycling of biopolymers. These, or similar, studies are required to provide a more complete picture of the potential effects of a transition from non-renewable to renewable polymers, thus allowing material selection decisions to be made with greater confidence throughout the packaging supply chain.
SMART authors: Shahin Rahimifard , James Colwill