Concrete Waste Recovery and Emissions Reductions in the Norwegian Concrete Industry
Abstract
Concrete is recognised as one of the most available and durable building materials. As a result, it is widely used and in large quantities. This is in its significant contribution to our greenhouse gas emissions and depletion of natural resources. This master's thesis explores the sustainability of concrete by examining concrete manufacturers and their potential to improve their sustainability profile. The research question has been: how can the concrete industry improve its sustainability profile with the re-use of surplus fresh concrete and its by-products? The methods used to answer the question include life cycle assessment, empirical work, and a literature review. The concrete producer Ribe Betong was selected as a case example for the thesis.
The literature review and case study combined with the life cycle assessment showed that in addition to greenhouse gas emissions from concrete, concrete waste exposes our nature to undesirable climate impacts. The empirical work consisted of a full-scale dry washing test and laboratory work on the durability of the aggregate used for washing. Even though the aggregates can be seen as suitable for the production of new concrete, the washing procedure leads to a higher environmental footprint from the concrete manufacturer and produces large amounts of by-products.
It is found that concrete producers focus on sustainability but have improvement potential concerning their impact on the environment. A clear framework provides the prerequisites for achieving improvements and meeting expectations from society. Furthermore, proper understanding and competence can help create fertile ground for innovative and sustainable solutions for the concrete producers and their local environment.