| dc.description.abstract | Plastic Pollution is a global problem that needs urgent attention, especially in developing countries
where waste management systems are underdeveloped or non-existent. Sustainable methods of (plastic)
waste management are costly. Using plastic as feed stock to produce building materials is a recent
innovative and sustainable way of management plastic waste. This thesis explores the sustainability of
this application for plastic waste, using an ongoing plastic waste recycling project in Casamance, Senegal
as a case study.
The Life Cycle Sustainability Assessment (LCSA) Framework defined as the sum of Life Cycle Assessment
(LCA), Life Cycle Costing (LCC), and Social Life Cycle Assessment (SLCA) was applied in this study.
Moreover, a literature review as conducted to derive recommendations for production of quality building
materials at the established Plastic recycling facility.
The LCA results showed that mechanical recycling is beneficial to the environment as evidenced its
negative contributions to all impact categories. For example, recycling 100 kg of plastic waste reduces
global warming, terrestrial toxicity, Human non-carcinogenic toxicity, and fossil depletion by 88.56 kg
of CO2 eq, kg 1,4-DCB, 127.46 kg 1,4-DCB, and 110.68 kg oil eq, respectively. Production of building
materials negatively impact the environment due to material and energy inputs. However, this application
is preferred to Open dumping, which, is the current means of dealing with plastic waste in area
of study. Using Solar energy for Paving Block production instead of Propane gas significantly reduces
environmental impacts. Moreover, expanding collection of plastic waste to Ziguinchor (100 km away)
only increased the environmental impacts during collection. The LCC estimated the total LCC of the
plastic recycling project over 20 years to be 458.27 million XOF. Also, a high upstream cost associated
with technical expertise was observed. The project positively impacts the stakeholder categories of
Workers, Local community, and society. Workers have freedom of association and collective bargaining,
are paid fair wages, and there was no evidence of forced labor. In the local community, there is respect
for cultural heritage and indigenous rights, the project contributes to economic development and secure
living conditions, and only employs locally. However, unfair wealth distribution was observed in the
value chain of the plastic recycling system. Plastic waste collectors participate on voluntary basis and
are not compensated in monetary terms. The application of plastic waste to produce building materials
is a sustainable means of containing and managing plastic waste in developing countries. The quality
of the manufactured paving blocks are dependent on optimum mix ratio (1:3) of plastic-to-sand, proper
temperature control, single of use plastic types per production batch, and thoroughly cleaning the PSW
before melting are advised for production of quality paving blocks.
Although the above conclusions are based on a specific to this case study, the results from this study can
be used to support future plastic waste management and investment decisions in developing countries. | |