Scenarios for concrete-rubble recycling in the Netherlands

Scenarios for concrete-rubble recycling in the Netherlands: An evaluation integrating Life Cycle Assessment and Life Cycle Costing

Miranda Xicotencatl, B.

Hu, M. (mentor)
Di Maio, F. (mentor)
van Roekel, E. (mentor)

Technology, Policy and Management

Engineering Systems and Services; Values, Technology and Innovation

Industrial Ecology Joint degree Leiden & Delft

2017-01-27

The Master's programme Industrial Ecology is jointly organised by Leiden University and Delft University of Technology. - Two main features of the construction and demolition systems translate into environmental pressure; an increasing need for building materials, to provide and maintain the infrastructure for growing urban populations, and the management of large amounts of waste streams that come from demolition and construction activities. Because of its high volume and limited management alternatives, the concrete waste is a critical stream. In the Netherlands, 95% of concrete rubble from construction and demolition waste is recycled into an application of lower grade through regular crushing. Alternative methods for reintegrating the coarse fraction into new concrete are Advanced Dry Recovery (ADR), electrical fragmentation (EF) and wet processing. Around 2% of the concrete waste stream is wet processed, but this alternative is energy intensive and expensive. Oppositely, ADR and EF are simpler technologies that also offer to retrieve the value of concrete, but are still at a pilot stage. This research project focuses on ADR as a recycling alternative to regular crushing in specific scenarios, addressing financial and environmental implications through the use of Life Cycle Assessment (LCA) and Life Cycle Costing (LCC). The main research question is: What are the environmental and economic implications of different concrete recycling scenarios in the Netherlands? The applicability of the results is that of a first estimate of the economic and environmental implications of shifting to ADR concrete-rubble recycling, with a detailed coverage of costs and types of environmental interventions. The research question is addressed from two different perspectives. First, a case study from the HISER project, sponsored by the European Union, is evaluated integrating LCA and LCC. The case is about the demolition of an end-of-life building and the construction of a new building on the same site where the old building stood. Therefore, it includes a waste management component and a material supply component. The materials retrieved from the demolition of a building were registered and the materials required for the new building estimated. As the demolition of a building is a one-time event, the real demolition and the construction plans are compared to a virtual demolition and the consequent construction plans. The scenario from the real demolition promotes circularity regarding coarse aggregate for concrete production, by recycling with ADR the clean concrete rubble from a ‘best-practice’ demolition. Second, with the Life Cycle Inventory (LCI) from the first perspective, the environmental implications of using recycled coarse aggregate instead of natural coarse aggregate for the production of concrete are explored. Regarding the impact assessment method, the modelled environmental interventions were better represented with the PEF characterization factors than with the EN15804 characterization factors. The integrated LCC-LCA study indicates that recycling concrete rubble into coarse aggregate for concrete with ADR technology provided environmental benefits at a higher cost for the Steiger 113 project, compared to the virtual option of processing the stony fraction through regular crushing and sourcing imported gravel for the new construction. The reduction of transport distances between the source of CDW, the ADR facilities and the consumer of the RCA would decrease the costs and the environmental burden. Within the defined scenarios from two different perspectives, the supply chain of RCA from concrete-rubble recycling with ADR technology presents environmental advantages compared to the supply chain of NCA. The Circular Economy Index presented advantages compared to mass recycling rates while contrasting the LCC environmental profiles with simple indicators.

Demolition
Waste management
Life Cycle Assessment
Life Cycle Costing
Concrete recycling

http://resolver.tudelft.nl/uuid:1eb96393-0d86-476b-b563-5a4035104b66

Student theses

master thesis

(c) 2017 Miranda Xicotencatl, B.