Essay: Life Cycle Assessment Of Plastic Bags: Impact, Alternatives, And Sustainability.

Questions to get you started thinking and writing:

1. Is Soling’s challenging claim relevant/valid for today? Does it make sense to his audience? 4

2. How does Soling attempt to establish a “relationship” or common ground with his audience to make his argument “matter” to readers? What technique(s) does he use to appeal to his audience’s feelings? How do the feelings he arouses in his readers make them accept his arguments more easily?

3. How does Soling enhance his arguments? Does he explain them through well-known facts and relevant examples? Does he connect them clearly? Does he acknowledge and refute opposing arguments?

4. To what extent does Soling achieve his purpose?

Overview of Life Cycle Assessment

The Life Cycle Assessment or LCA of a product analyses the whole process from its origin to end and is referred to “Cradle to Grave” analysis which allows us to understand the impact a product creates in the process of it manufacturing, use and disintegration. The LCA is assessed by ISO 14000 environmental standards. The standards that define LCA are according to the ISO: 14040 standards and generally followed while assessing the life cycle impact of a product. The report will perform a Life cycle analysis of three different plastic bags that are generally in use. The Low Density Polyethylene, the long life Polypropylene, and the bio-degradable bag have been taken for the assessment. The growing use of plastic bags and their impact in the environment has been huge and therefore this product has been selected. Plastic bags are extensively used in the present resulting in generation of huge amount of wastes. The bags are the most common form of degradation of the environment.

The process of assessing the Life Cycle of a product includes a stage-wise process that overviews the process in the lifetime of product. The ISO 14040 standards refer to three stages that identify the stages of development use and disintegration or recycling in the case of a close looped system. The stages can be represented in a schematic chart as follows: 

The ISO standards define the processes in three different stages as mentioned in the steps beside. The goal and scope includes necessity of assessing Plastic bags, the inventory analysis discusses inputs and the outputs. A cradle-to-grave involves all the stages in the production of the product: from raw

material extraction and transport to production sites and consumption, until the re-use or the disposal of the finished good.

The goal of this LCA report is to compare the different types of grocery bags in their complete life cycle. The production or manufacturing, use and disintegration or recycling of these bags will be analysed to understand their impact over their life cycle. The goal of the report will also analyse the functional unit of the product, the processes, and the number of stages defining the start and the end point of the product.

The Inventory analysis involves the production flow chart, accumulating data and information, evaluating the inputs and the outputs of the system and comparing the alternative products.

The final stage is the impact assessment, and relates the findings of the inventory analysis and thereby evaluates them with respect to their outputs in the environment. The analysis includes the impacts that are created in the various stages of production transportation usage and end of life. 

Comparison of Different Plastic Bags and their Usage

The following table compares the various materials used for manufacturing plastic bags over the time.

 The weight of the material includes is calculated per gram of a single unit of plastic bag. The functional unit of bag is derived from its usability.  The functional unit is therefore measured in terms of the usage of the bags. The number of times the bag is used will be treated as the functional unit of the bag. The HDPE bags are of single use, the PP bags are used for 2 times and the bio degradable bags are used at least 8 times. The overall weight calculated in terms of annual usage. The weight referred in the table includes the general weight. The weight of the plastic bags is calculated till the product is either recycled or is passed to the next step of degradation. The table below will represent the national consumption of plastic bags (Greene, 2011).

The material flow of Plastics bags can be understood from the following flow diagram which will explain the cradle to grave process of the material.                                             

During the material flow processes there are several inputs and outputs that are derived which add to the environmental impact that the product create in the whole process. The several inputs that involved in the material flow include energy resources, transport, and water resources. The resources that are involved in the process come out as outputs in the form of various toxic emissions, several water discharges and solid wastes. Some by products and recyclable wastes are also derived through the material flow process (Mori et al. 2013).

The Impact analysis of plastic bags and bio-degradable bags can be evaluated from the material flow that has been derived. The major impact that HDPE single use plastic bags create is during its end of life if not recycled. The HDPE bags take a very long period of time to disintegrate in the environment. The alternative Bio-degradable bags, mostly Paper bags take a lesser time and completely disintegrate in the environment.

The above table gives a brief idea about the impact created by the plastic bags and its alternatives. The bio degradable bags refer to the Paper bags in the table. The impact created on the environment is categorised into several categories and an impact rating has been done by Dr. Karli Verghese, and is shown in the following table. The least impact according to the table has been shown by PP Bags that are long life Polypropylene bags and are reusable.

Material Flow Analysis of Plastic Bags

The table above proves that PP bags that are used have the lowest impact on the environment and these should be implemented an input to practice.  The impacts were analysed based on the global warming, photochemical oxidation and eutrophication, land and water use, solid waste generation and fossil fuel use (Verghese et al. 2009). The impacts of plastic bags were studied over secondary literature to understand the effect of these bags in the environment cycle.

The hotspot refers to the stage in the material flow which creates a maximum impact in the environment. The end use of the plastic bags as compared to paper bags has been highly detrimental owing to their longevity. The hotspot of the plastic bags can be identified in the stages of production from pellets to films. The maximum impact to environment is created in this stage and therefore reduction in the film thickness can reduce energy intake (Verghese et al. 2009). Along with the use of renewable energy resources during manufacturing can also reduce the impact. For the case of creating litter, bio-degradable bags or paper bags will have the lowest impacts. They can be recycled effectively and degradation is also less harmful.

Given the scenario of plastic bags, the best alternative can be suggested that paper bags have the lowest impact in terms of degradation while the PP bags have the lowest impact in the environment in overall material flow. Thus the best alternative would be long life Polypropylene bags that would have minimal effect in the environment and would create the environmental sustainability with proper management.

Conclusion:

The importance of analysing the Life Cycle of a product lies in the evaluation of the productions impact on the environment. The growing environmental pollution and the effect of the products in the whole life cycle were not evaluated yet this contributed a major part in the global environmental degradation. The life cycle assessment of a product helps us to understand the impact that a product creates from its inception to its grave or disintegration back into the environment and quantify the amount of impact created, to compare between better alternatives. This report with its evaluation of the life cycle of plastic bags gives us an insight into the impact they create and the alternatives that can be used.    

References

Wichai-utcha, N. and Chavalparit, O., 2018. 3Rs Policy and plastic waste management in Thailand. Journal of Material Cycles and Waste Management, pp.1-13.

Greene, J., 2011. Life Cycle Assessment of Reusable and Single-use Plastic Bags in California. CSU Chico Research Foundation.

Environment.act.gov.au (2018). Which bags are banned and which are allowed? - Environment, Planning and Sustainable Development Directorate - Environment. [online] Environment.act.gov.au. Available at: https://www.environment.act.gov.au/waste/plastic-bag-ban/which-bags-are-banned-and-which-are-allowed [Accessed 27 Oct. 2018].

Hauschild, M.Z. and Huijbregts, M.A., 2015. Introducing life cycle impact assessment. In Life Cycle Impact Assessment(pp. 1-16). Springer, Dordrecht.

Verghese, K., Lewis, H., Fitzpatrick, L., Hayes, G.M. and Hedditch, B., 2009. Environmental impacts of shopping bags. Report for Woolworths Limited, Ref. number: SPA1039WOW-01, pp.1-36.

Environment.gov.au 2018. [online] Environment.gov.au. Available at: https://www.environment.gov.au/system/files/resources/c8dd95af-c028-4b6e-9b23-153aecbf8c3c/files/australian-plastics-recycling-survey-report-2016-17.pdf [Accessed 27 Oct. 2018].

Mori, M., Drobni?, B., Gantar, G. and Sekav?nik, M., 2013. Life Cycle Assessment of supermarket carrier bags and opportunity of biolpastics. Proceedings of SEEP2013. Maribor, Slovenia.

Narodoslawsky, M., Shazad, K., Kollmann, R. and Schnitzer, H., 2015. LCA of PHA production–Identifying the ecological potential of bio-plastic. Chemical and biochemical engineering quarterly, 29(2), pp.299-305.