Vattenanvändning och möjligheter till vattenbesparing hos kemiklustret i Stenungsund

Water use and opportunities for water savings at the chemical industry cluster in Stenungsund Water scarcity is a growing problem in Sweden, as well as internationally, due to increasing demand for water and the impact of climate change. This is the case in Stenungsund where the ability for the municipality and industry to expand is limited by the availability of water from the local lake, Stora Hällungen. Working with the four largest industrial sites in the Stenungsund industrial cluster, Perstorp, Nouryon, Borealis and INOVYN, this project focused on mapping water use in the cluster by testing and further developing a tool for mapping of water use in industry. The flow of water through the industrial sites, its uses, treatment approaches and aggregated water quality data were included in the mapping and is presented using visual outputs generated from the tool. A methodology for water quality assessment and grouping was also developed and included in the tool. Results of the mapping were used as foundation to investigate opportunities for water savings through improved efficiency and reuse of wastewater streams. Measures to improve water efficiency include minimisation of the volume of reject water in treatment processes, sequence optimisation for reducing water use in cleaning and optimisation of steam and cooling systems. Opportunities for water reuse include the reuse of wastewater or stormwater for cooling at Perstorp and the Borealis PE site, and the recirculation of wastewater from the Borealis Cracker. Critically, the incentives for individual companies to implement water savings and reuse measures are a decisive factor in their implementation. Given this, a next step from this work would be to conduct a more comprehensive risk analysis to investigate future needs of the various stakeholders with respect to water and water supply risks. From these results a pinch analysis considering water quality could also be conducted to find further opportunities for water reuse