Water flow analysis of Jästbolaget : An assessment of the yeast production’s environmental impact, caused by its water consumption

Abstract: This bachelor thesis is carried out for the department of Industrial Ecology at the Royal Institute of Technology in Stockholm. Water in Sweden is a resource in abundance. Even so, it is an expensive one and may even become more expensive due to climate changes. Hence, there are for companies’ both economic and environmental benefits to induce minimization of the water flow. The aim of this report is to assess the sustainability of the water usage within the production of liquid, active dry and compressed fresh yeast which also goes under the common name of baking yeast. The assessment has been done through a water flow analysis in addition with a water footprint. The system borders for the water flow analysis comprises the outtake of water from Mälaren, the production at Jästbolaget and the final treatment at Käppala wastewater treatment plant. The water considered in the production is mainly the municipal-water flow within the production and to a less extent the water used for cooling. Substances contained in the water flow which are paid particular attention are the amount of total organic carbon, phosphorus and nitrogen. The method for gathering information and data has been through interviews and mail correspondence with employees at Jästbolaget and Käppala. Furthermore, a literature study has been conducted. The conclusion of this report is that the water flow has a low impact and that Jästbolaget has taken appropriate measures to minimize their impact and usage of water. However, improvements can always be made but it is rather a matter of the methods efficiency to further decrease the usage of water and emission of phosphorus and nitrogen.