Ismael Arroyo Tena
UNIVERSIDAD DE GUANAJUATO, Research Group on Industrial Ecology
Biochemical Engineer specialized in Environmental Engineering by the Technological National Institute of Mexico. Currently student of the Water Sciences Master's Program at the University of Guanajuato, Mexico. Developing thesis under the research line of water footprint in the tanning industry in Guanajuato, Mexico.
The water footprint (WF) is defined as an indicator for the appropriation of fresh water resources and its anthropogenic effect not only in the direct use of water by a consumer or producer, but also in its indirect use. The WF concept was introduced by A. Hoekstra in 2002, and it has gained interest since it considers water use along the supply chains.
There are two methodologies for the calculation of the WF. One is described by the Water Footprint Network (WFN) and it is applied to processes, products, consumers, countries and companies. The other is based on life-cycle assessment (LCA) perspective (NOM ISO-14046) and it is focused on the use of water throughout the development of a product.
Since WF is a recent concept, existing methodologies do not cover certain aspects of calculation for specific cases. For instance, there is not yet a methodology for WF calculation of an industrial product that considers the type of the enterprise (number of employees and production volume) and available technologies within a defined geographical region.
OBJECTIVE
To describe a detailed methodology applicable for an industrial product processed within a defined geographical region, considering the type of the enterprise and available technologies combining aspects from the LCA approach and the WFN methodology.
METHODOLOGY
For the methodological adaptation of the WF calculation for an industrial product, elements of the two internationally approved methodologies were coupled. The methodology described in the Water Footprint Assessment Manual: Setting the Global Standard, which provides a comprehensive guide of methods for the evaluation of WF, and also some aspects from ISO-14046-2014 that contains the principles, requirements and guidelines for the calculation of WF based on the LCA. The novelty of this adaptation is that specific factors such as geographic region, type of enterprise (number of employees and production volume) and process technology were included.
RESULTS
The system is delimited from the materials reception to the obtention of the product, for a determined region. Different types of companies are differentiated, determining their level of impact on the WF of the process in the studied region. This differentiation considers the type of company and the technology used. The WF of the industrial process is divided into its components blue and grey.
To calculate the WF of a product, it is considered that different inputs generate different WF depending on the place of origin in question. The WF of each input is calculated separately according its place of origin. The participation rate per region is evaluated for the total of inputs processed. The formulae that support this adaptation are shown.
CONCLUSIONS
An adapted WF calculation methodology was described. This methodology may help the industrial sector and also governments or academy to get a better water resources management, since important factors that influence the final WF of a product aspects were included. The methodology distinguishes the three components of the WF.
• Advances in methods (e.g., life cycle assessment, social impact assessment, resilience a , • Decision support methods and tools
