In modern society in terms of economics and environmental impact, it is important to ensure that a company is as energy efficient as possible to reduce the amount of energy used. About 10 TWh of electricity used annually to pump drives in Swedish industry. Therefore, pumping system has great potential for energy savings. The objective of this report was to determine how much energy and money that can be saved with the insertion of variable speed drive to six pumps on Bleach plant 4 in Skutskär Mill. The work was performed with electrical measurements during one week, analysis of pump curves and the compilation of production data over a year. The results show that four of these six pumps were profitable and yielded an annual saving of 1172 MWh of electricity and 560 000 SEK. With an economic lifetime of 10 years and a discount rate of 6.8% the final result for the entire life-cycle savings became 3 355 000 SEK. The conclusion was that it is preferred to introduce variable speed drive on pumps with a motor power above 50 kW.

This thesis aims to produce a control strategy that minimizes the energy usage of the pumps in the sewer system of Växjö City. The pumps are located in a small number of pumping stations. These are connected by a network of pipes in a way that requires the control of the pumps to be coordinated, both within and between the pumping stations. A model of the system based on fluid mechanics is proposed and from this an optimization problem is constructed for the control problem. When the optimization problem is reformulated as a hierarchy of smaller problems these problems can be solved sequentially and the computational requirements are low. The resulting control strategy gives an optimal control at each flow rate to the waste water treatment plant, and the results show that an optimal control can yield significant energy savings. The control strategy is also shown to be stable with regards to errors in the model. / Detta arbete syftar till att beräkna en energieffektiv styrstrategi för pumpar i spillvattensystemet i Växjö stad. Pumparna finns i ett fåtal pumpstationer som är sammankopplade via ett rörsystem så att styrningen av pumparna behöver koordineras, både inom och mellan pumpstationerna. Utifrån en framtagen fysikalisk modell av systemet formuleras ett optimeringsproblem för att finna en energieffektiv styrning. Detta problem kan lösas på korta beräkningstider genom att det delas upp i en hierarki av mindre delproblem som löses sekventiellt. Den resulterande styrstrategin ger en optimal styrning för olika totala flöden i spillvattensystemet, och resultaten visar att en effektiv styrstrategi kan ge påtagliga besparingar i pumparnas energiförbrukning. Styrstrategin har även studerats gällande känslighet för viss osäkerhet i modellen och uppvisar stabilitet.

In November 2016 a brand new and highly technological hospital called New Karolinska Solna opened in Stockholm. In connection with the planning of the hospital, new medical devices were procured, including a new infusion system that is now in use. Previously, each ward at the hospital had their own pumps and was responsible for updates and maintenance. Now, the hospital will instead have a floating pump system, which means that the hospital will own the pumps. The infusion pumps will be floating between the wards without being linked to a specific ward or department. The updates that were previously done when the need arose at the ward will now be a common process for the entire hospital. The aim of the project was to develop new guidelines for how the update process should be done on New Karolinska Solna's new infusion pump system. Through interviews with key personnel during the procurement process, the medical technicians department and caseworkers, new guidelines have been written, given the already existing technical conditions. During the course of the project it has been found that there are major shortcomings of information and communication within the hospital. The guidelines presented in the result are an important part to ensure that information related to the update comes to the caregivers at New Karolinska Solna, thus simplifying and streamlining the update of the infusion pumps.