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This thesis reports on the research undertaken to reduce the water usage within manufacturing through modelling and improving the water efficiencies at both process and production system levels. The primary objectives of this research are: to develop a framework which classifies the various water usages within a manufacturing facility, to define a number of efficiency ratios to highlight the water inefficient activities, and to develop a decision support tool to aid with the selection of the most effective solutions for reduction of water usage within manufacturing applications. The research undertaken in the past three years is divided into four main parts. The first part reviews the relevant literature on water availability and distribution, the role of water in manufacturing, and relevant legislations and policies governing the water usage in manufacturing industries. The review also includes assessment of current water flow modelling and wastewater management tools and technologies. The second part introduces a Manufacturing Water Usage framework which classifies the water usage within a manufacturing facility as production-related and non-production-related water. The Production Water, which is the main focus of this research, is further classified as Process and System Water required to produce a product. Process Water is defined as the water used directly by the production processes, whereas System Water is defined as the water used to support the operation of a process and/or to maintain the production equipment. The framework also incorporates the definition of a number of Water Efficiency Ratios to determine the water critical processes. The third part of the thesis describes the implementation of this framework within a water simulation model as the main engine for a water reduction decision support tool. The final part of the thesis demonstrates the utilisation of this tool to support the decisions aimed at reducing water within a real food production line. In summary, the research has concluded that the consideration of water reduction scenarios within the manufacturing industry requires a detailed understanding of where and how water is used at production process level, and utilisation of this knowledge to develop a series of proactive approaches based on product/process redesign and radical operational planning improvements.

Det hydrologiska systemet i Dannemorasjöns avrinningsområde, beläget i norra Uppland, är mycket komplicerat och har förändrats genom åren på grund av mänskliga ingrepp. De naturliga sjöarna i området har vid flera tillfällen utsatts för stora sänkningsföretag, vars främsta syfte var att förhindra läckage till gruvan i Dannemora. Sjöarna har under lång tid använts som recipienter för samhällena och industrierna i Dannemora och Österbybruk. I området finns det flera dammar som användes som magasin för kraftproduktion till gruvan och järnhanteringen. Flera av dammarna skapades redan på 1600-talet. Syrgassituationen i Dannemorasjöns avrinningsområde är på många håll ansträngd och problemen har särskilt uppmärksammats för Dannemorasjön, Harvikadammen och Sundbroån men även andra sjöar i området är drabbade. Målsättningen med denna rapport är att kartlägga hydrologin i Dannemorasjöns tillrinningsområde, sammanställa fakta om dammar, vattendomar och genomförda vattenföretag, samt utarbeta ett förslag på förändring av flödesregimen och vattendragens utformning för att förbättra syrgasförhållandena i Dannemorasjön. För att kunna se hur en förändrad flödesregim påverkar syrgasförhållandena i Dannemorasjön har en flödesmodell upprättats för sjöns tillrinningsområde. Huvudsakliga indata har varit observerad specifik avrinning från Vattholma, strax nedströms Dannemorasjön. Till flödesmodellen har en modell som simulerar syrgashalten i Dannemorasjön vintertid kopplats. Simuleringsresultaten visar att en förändrad flödesreglering vintertid kan förbättra syrgassituationen i Dannemorasjön. För att denna regleringsstrategi ska bli effektiv krävs dock större magasineringskapacitet i dammarna eller tillskott av vatten genom t.ex. pumpning. Det framgår även från simuleringsresultaten att en vattenståndshöjning i sjön skulle gagna syrgassituationen under senvintern, dels p.g.a. en ökad total mängd syrgas i sjön vid isläggningen, dels genom en minskad syretäring per volymsenhet. Under vintrar med en lång isperiod samt liten tillrinning blir syrgasförhållandena i sjön extra kritiska. Sådana säsonger räcker det inte med en enskild åtgärd utan det krävs flera samordnade åtgärder för att skapa en acceptabel syrgassituation i sjön. / The hydrological system in the catchment area of Lake Dannemorasjön, in the northern part of Uppland, is very complicated and has been changed many times by human activities. The water level of many lakes in the area has been lowered at several occasions. Most of these operations have been made in order to prevent leakage from Lake Gruvsjön to the mine in Dannemora. Already in the 17th century many of the wetlands were dammed up to be used as water storage for water power production. The power was needed for the mine and iron production in the area. Many lakes have also for a long time been used as recipients for waste water. The oxygen content in the lakes and rivers in the area has frequently been reported as very low, especially in Lake Dannemorasjön, Lake Harvikadammen and the River Sundbroån. The aim of this study is to describe the hydrology in the catchment area of Lake Dannemorasjön, compile facts about the regulated spillways of the reservoirs and water regulation vertictsand to work out a plan for changing the water regime in order to increase the oxygen content in Lake Dannemorasjön during winter. A model that simulates the flow of water within the catchment and to Lake Dannemorasjön was developed. Another model that simulates the oxygen content in Lake Dannemorasjön during ice covered conditions was attached to the waterflow model. The results from the model show that a change in the regulation of the flow to Lake Dannemorasjön can increase the oxygen content in the lake. A prerequisite for the new regulation to be effective is that the storage capacity of Lake Harvikadammen is increased or that additional water is supplied to the dam, for instance by pumping water from Lake Dannemorasjön. It is also clear from the study that a raised water level of the lake would affect the oxygen content in a positive way. The oxygen problem becomes particularly serious during cold Winters with a long lasting ice cover. During such Winters it is not enough with just one measure to prevent oxygen deficit, several different kinds of measures must be undertaken in order to make sure that the oxygen content stays at a reasonably level.