Optimisation of a Textile Washing Process Based on Life Cycle Sustainability Assessment Results

EU directives identified the textile sector as a key area for environmental, economic, and social assessment and process optimization, particularly in relation to water and energy use,  core focus of the CALIMERO project.

We are analyzing the high-temperature washing process of “Teintures et Impressions de Lyon (TIL)”, which involves the removal of cellulose from fibers, a water and energy-intensive process. To reduce the environmental burden of the process, we consider two aspects: (1) analysis of LCSA results of the current scenario and (2) process optimisation based on the previous step.

Considering the first aspect, we include Life Cycle Assessment (LCA), Life Cycle Costing (LCC), and Social Life Cycle Assessment (S-LCA). For LCA, we aim to follow the Product Environmental Footprint approach, based on the inventory data collected from the company TIL for all relevant flows (heat, electricity, water usage). The ecoinvent 3.9.1 database is utilized to cover background processes.

In the second step, namely the optimisation, we exploit the potential to recover heat from the washing water by integrating a suitably sized heat exchanger, which is of main concern. The challenge in this task lies in carrying out an optimisation built not only on thermodynamic properties that lead to calculate the most suitable heat exchange area, but also based on the results of step (1). The goal of the optimization is indeed to find the best solution that minimizes the economic costs and environmental burdens, while providing a social benefit. While considering the LCSA results of step (1), we also add the LCSA of the potential heat exchanger installed in the advanced configuration.

The challenges arise due to the absence of defined datasets for heat exchangers, and in defining the function that assess all the revelant parameters.

To overcome the first issue, a new dataset will be created for the specific heat exchanger, using data from relevant literature. For the second, a technoeconomic and social function will consider standard economic indicators, job creation potential and environmental CAPEX and OPEX”, which correspond respectively to the additional life cycle impacts of the heat exchanger for its manufacture & disposal, and avoided operational impacts of the boiler.

The ultimate goal is to achieve the best design condition that results in a reduction in energy and water usage, thereby directly optimize the industrial process and indirectly improving sustainability impacts.