Free Resources

Introduction

Advances in science and technology has resulted in the production of synthetic polymers with great properties like high resistance, stability, durability and longevity; much needed materials which are essential in the improvement of our daily lives, with Polyethylene Terephthalate (PET) being at the forefront of these essential synthetic polymers (Raheem et al., 2019). Since its appearance on the global scene, PET has contributed immensely to the advancement of the human society in various sectors, replacing various materials for application on different fronts (Pacheco-Torgal et al., 2012). This has resulted in the continual exponential growth in its global demand (Chu et al., 2021).  It has shown that it can be used industrially for packaging a wide range of processed products in different states (Wei et al., 2019).  Its intrinsic properties imparts this versatility it possesses; with compatibility, lightness, reasonable inertness, transparency and longevity being amongst its significant properties (Dubelley et al., 2018).

Over the years, the global production of PET has increased exponentially owing to its continual exponential global demand rate, as forecast also depicts that PET production would still improve its exponential production rate in the nearest future (Okunola et al., 2018). Combining these production rates with the continual increase in the global production poses a serious global threat – an exponential increase in plastic waste generation translating to the deterioration of ocean life and carcinogenic concerns for the human society (Yuan et al., 2020).

Despite the benefits of PET, it raises several environmental concerns throughout their life cycle due to its rising production, a major environmental challenge is raised as it is produced from fossil fuels (crude oil or gasoline) and takes a long time to biodegrade or photodegrade; around 1-3% in 100 years with a bio-based alternative only recently being exploited commercially (Shahidan, 2018). This dramatically increases the packaging waste in the already crowded disposal sites. Fossil-based resources are finite and impact the environment negatively throughout the extraction, production and utilization processes (World Economic Forum, 2016).

In as much as the production of PET does not directly pose a serious threat to the environment, its resulting waste degrades landfill sites, obstruct sewage systems, and also engenders the breeding of pests and other micro-organisms translating to the global deterioration of ocean life (You et al., 2020). Globally, the deposition and accumulation of PET wastes in the ocean environment increases exponentially with every passing year (Parolini et al., 2020).  It has been observed in the UK that most PET bottles produced are not properly disposed (Forrest, 2019). But new bottles are produced daily, thus, increasing the litter in the country without alleviating the menace posed by it, they constitute a nuisance in our environment, and they are found littered in all nooks and crannies within the various geographical regions (Heindler et al., 2017).

These are hazardous because they can cause flooding and can easily be ingested by marine fauna. The PET can then work its way up the food chain and increase in concentration as larger animals feed on lower trophic levels (Stanica-Ezeanu and Matei, 2021).

The environment responds to virtually all manipulative and destructive activities of man on the earth surface including solid waste disposal (Tanaka et al., 2018). Solid waste as noted as one of the most acute types of environmental degradation that has engulfed and blighted our cities in recent years (Das et al., 2019). Disposal and accumulation of solid waste indiscriminately at different spot contribute to land degradation and pollution (Rodrigues et al., 2018). 

Despite the benefits of PET, it raises several environmental concerns throughout their life cycle due to its rising production, a major environmental challenge is raised as it is produced from fossil fuels (crude oil or gasoline) and takes a long time to biodegrade or photo degrade; around 1-3% in 100 years (Koshti et al., 2018). This dramatically increases the packaging waste in the already crowded disposal sites, these are hazardous because they can cause flooding and can easily be ingested by marine fauna (Tiso et al., 2021). The PET can then work its way up the food chain and increase in concentration as larger animals feed on lower trophic levels (Wei and Zimmermann, 2017).

The basic challenge for the beverage industries is to keep pace with the growing consumption. However, the increasing number of PET bottles constitutes a serious environmental problem when used bottles are not disposed of properly (Malik et al., 2017). As such the usage of PET bottles causes little harm to the environment compared with its end-of-life phase (Snell et al., 2017).

Post-consumed PET bottles are non-biodegradable waste; they constitute a nuisance in our environment, and they are found littered in all nooks and crannies within the various geographical regions (Wang et al., 2020).

To address this situation, different technologies have been developed in order to recycle the material or to recover its energy content (Nisticò, 2020). In this regard, the potential environmental, impacts on these technologies should be investigated through a life cycle assessment to create the appropriate evidence base in the UK (Gomes at al., 2019).

Problem Statement

The potential environmental hazard posed by various technologies used for the disposal of Post-consumer PET bottles through a comparative life cycle assessment (LCA) needs to be qualitatively and quantitatively assessed, and determined to create an appropriate evidence base and proffer solutions to the UK Government (Maga et al., 2019).

Aim and Objectives

The aim of this research is to evaluate the environmental impact of various technologies used for disposal of waste PET bottles in the most environmentally friendly approach in the UK through a comparative Life Cycle Assessment (LCA).

The objectives of the research work are; 

• Objective 1:  To gain further knowledge regarding LCA methodology. 
• Objective 2:  To carryout LCA for five different scenarios of waste PET bottles disposal in the UK.
• Objective 3:  To proffer solutions to the UK government on the disposal of waste PET bottles (Porta et al., 2020).

Research Questions

The identified research questions for this project are provided below:

• How is the LCA on waste PET bottles disposal in the UK carried out?
• What constraints are considered when carrying out the LCA?
• What methodological framework was used in carrying out this LCA?
• What database was used in carrying out this LCA?
• What sample size was used in carrying out this LCA?
• What impact could arise from this research work?

Deliverables

The deliverables of this project are a project report and an impact analysis.  Also, the report should contain a complete documentation of how the LCA was carried out, the methodology framework utilized, the database used, mitigations and solutions proffered after carrying out an impact analysis.

Relevance

This research mainly focuses on carrying out a Life Cycle Analysis (LCA) with respect to the PET bottles disposal (or lack of it)  in the UK (majorly after consumer use) by undertaking an investigation which majors on both quantitative and qualitative analysis.

The LCA would be carried out within the constraints of an appropriate methodological framework, and also using a suitable software to analyze the database. An assessment would also be carried out on the probable impacts.

Methodology

This project focuses on secondary research, LCA methodology and impact assessment, and they are discussed below:

Secondary research

The secondary research in this project will utilize a systematic approach (Johnson et al., 2016) to review the works of literature. The steps involved in the systematic review of the literature are provided below:

• Step 1: Identify the research questions that can be used for the project.
• Step 2: Identify the keywords that should be used to research the works of literature.
• Step 3: Extract the journals and books that are appropriate for this project.
• Step 4: Write the literature review chapter.

LCA methodology

The  LCA methodology is in stages namely:

• Stage 1:  Choice of Scenario
• Stage 2:  Sample size selection
• Stage 3:  Goal and scope definition.
• Stage 4:  Life Cycle Inventory (LCI).
• Stage 5:  Life Cycle Analysis (LCA).
• Stage 6:  Interpretation.

Impact Assessment

After the LCA is carried out, the probable impacts would be assessed in order to proffer solutions and build up mitigations.

Evaluation

The risk assessment conducted for this project is provided in the table below:

Table 1:  Risk assessment