Research Motivation
The construction industry contributes a big share to global warming and water use. Regarding Business as Usual and the future growth of the infrastructure and construction industry, ecological challenges arise. To build more environmentally friendly infrastructure, possible solutions such as resource-efficient technologies and the substitution of materials are required. Environmental impacts of the extraction process in the mining region are relatively high [1]. Considering the ambitious greenhouse gas emissions (GHG) reduction and efficient use of resources targets set by the Sustainable Development Goals (SDGs) and the importance of the construction sector, there is an increasing need to study the environmental performance with a focus on water footprint of the construction materials.

System boundaries of the life cycle phases and construction materials

The EN 15804 [2] has classified the life stages of a product, in this study, the focus is on the cradle-to-gate processes, which refers to A1-A3. For instance, A1–A3 production process of cement refers to raw material extraction (A1), transport of the raw materials (A2), and production process (A3), e.g., manufacturing of clinker, and cement grinding.

For the life cycle assessment, life cycle inventory (LCI) data and an LCA tool will be needed. Ecoinvent database [3] will be considered as the main LCI, however, other types of the database and previous publications can be considered for validation purposes. openLCA software will be use for the conduction of the LCA results and analysis, openLCA is an open access LCA software [4].

The main construction materials are related to steel, cement, brick, glass and insulation. However, specific materials should be also defined at the beginning of the study such as which type of cement and brick.

Water footprint
Water use of the construction has been studied considering different impacts in different studies, the work should have an overview of the methods that can address the water footprint. It should answer one of the research questions: Which footprint can address water use considering various parameters such as water availability, water demand etc. AWARE method [5] refers to assessing the impacts of water consumption based on Available Water Remaining. The ISO 14046:2016-079 standard proposed the water scarcity footprint [6], the applicability of the method has been used in many studies with the integration into LCA calculations.
 

Research Methodology

The work methodology will include the following steps:

1. Review indicators and methods to assess the water footprint.
2. Data of the water use of mining activities associated with the selected construction materials[s6] , including published studies and open access data.
3. Distribution of the water uses along the production supply chain of the selected construction materials.
4. Using openLCA software and ecoinvent database to account for the water footprint of the construction materials.
5. Analysis of the background database to check the validity and process chain of the life cycle inventory.
6. Results calculation per functional unit of the materials. This includes the definition of a suitable functional unit.
7. Spatial and activity-related hotspot analysis of the water use for the supply chain of the materials production.
8. Validation of the results by the comparison with previous literature and published databases.

Duration: approx. 6 months, start possible immediately
Supervisor: Dr. Husam Sameer (University of Bochum), Anna Schomberg (University of Kassel)
Place of work: primarily homeoffice, Center for Environmental Systems Research (Wilhelmshöher Allee 47) possible
Requirements: The work should preferably be assigned to a student (m/f/d) of environmental engineering.
Contact: Anna Schomberg (anna.schomberg[at]uni-kassel[dot]de)

References

[1] H. Sameer, S. Bringezu, Life cycle input indicators of material resource use for enhancing sustainability assessment schemes of buildings, Journal of Building Engineering. 21 (2019) 230–242. doi.org/10.1016/j.jobe.2018.10.010.

[2] DIN EN 15804 - 2022-03 - Beuth.de, (n.d.). www.beuth.de/de/norm/din-en-15804/344735627 (accessed May 6, 2022).

[3] ecoinvent, ecoinvent Version 3, (n.d.). www.ecoinvent.org/database/database.html (accessed August 12, 2018).

[4] GreenDelta, openLCA online: www.openlca.org, (2022).

[5] A.M. Boulay, J. Bare, L. Benini, M. Berger, M.J. Lathuillière, A. Manzardo, M. Margni, M. Motoshita, M. Núñez, A.V. Pastor, B. Ridoutt, T. Oki, S. Worbe, S. Pfister, The WULCA consensus characterization model for water scarcity footprints: assessing impacts of water consumption based on available water remaining (AWARE), International Journal of Life Cycle Assessment. (2017) 1–11. doi.org/10.1007/s11367-017-1333-8.

[6] A.C. Schomberg, S. Bringezu, M. Flörke, Extended life cycle assessment reveals the spatially-explicit water scarcity footprint of a lithium-ion battery storage, Commun Earth Environ. 2 (2021) 11. doi.org/10.1038/s43247-020-00080-9.