There is significant worldwide environmental concern related to the transportation of Invasive Aquatic Species (IAS) by ships ballast water into non-native environments. This has given rise to the development of a vast array of technological ballast water treatment systems. The complex environmental challenges and tight operational characteristics of marine vessels limits the scope of the technologies used for Ballast Water Treatment (BWT). As a result few technologies have progressed beyond the research and development stage; however one of the most promising technologies for ship board use is the cyclonic separator, or hydrocyclone. Despite the use of hydrocyclones in a wide variety of engineering applications they have yet to be successfully adapted towards the removal of suspended sediment and marine organisms from large volumes of ballast water. The following primary objectives of this study have been met: • Via critical review identify the technological solutions for treating ballast water best suited to onboard use. • Define the critical flow regimes evident within hydrocyclonic separators. • Establish a series of Computational Fluid Dynamics (CFD) simulations, evaluating standard turbulence models in order to determine the capacity for commercial CFD to model hydrocyclonic flow. This study has detailed the operational characteristics of ballast water hydrocyclones with the aim of enabling hydrocyclones to be optimised for individual ship configurations. Flow simulations have been conducted using CFD, and in particular the Detached Eddy Simulation (DES) turbulence model. Finally the DES model is shown to be a legitimate turbulence model for hydrocyclonic flow regimes, validated against empirical and experimental data.

Advanced oxidation technology (AOT) has been used to destroy microorganisms in ballast water by breaking down the cell membranes. The primary objective of this study was to determine the effects of a ballast water treatment system that uses a combination of UV-C (λ=254 nm), Vacuum-UV (VUV; λ=185 nm) and photocatalytic titanium dioxide (TiO2) on a freshwater algae, Pseudokirchneriella subcapitata, and a marine algae, Tetraselmis suecica. The coupling of a semiconductor, such as TiO2, with a UV source is known as an advanced oxidative technology (AOT). To test the effects of TiO2 and wave length on algae, dose-response experiments were conducted to determine the species median lethal dose (LC50) for each of the following treatments: UV-light emitted at 254 nm (UVλ=254 nm), UV-light emitted at 254 nm in the presence of TiO2 (AOTλ=254 nm), and UV-light emitted at λ=254 nm (90 %) and 185 nm (90 %) in the presence of TiO2 (AOTλ=185 + 254 nm). In both species, TiO2 significantly increased mortality, most likely due to the biologically harmful radicals generated at the TiO2 surface. The addition of the 185 nm wavelength significantly increased cell mortality in P. subcapitata, but not in T. suecica. Across all three treatments, P. subcapitata was more sensitive than T. suecica. The secondary purpose of this study was to assess the applicability of ImageJ, an image analysis software, for highthroughput data to analyze the effectiveness of ballast water treatment. ImageJ has been used to rapidly and accurately perform cell Live/Dead analysis; however, several hurdles were identified.

Arbetet behandlade vilka konsekvenser inom driften (ekonomiska kostnader och teknologi) som rederier kommer att drabbas av när IMO:s barlastkonvention träder i kraft då barlastvattnet måste renas innan inträde i Östersjön. Arbetets syfte var att få fram vilka konsekvenser det blir för rederier när IMO:s barlastkonvention träder i kraft. Resultatet skulle jämföra skillnaden mellan lag och rekommendation då Helsingforskonventionens rekommendationer baseras på IMO:s barlastkonventions krav. En kvalitativ metod valdes för att komma fram till resultatet, i form av en öppen intervjustudie, där fyra olika företag har intervjuats. Syftet med intervjuerna var att se ifall de följde Helsingforskonventionens rekommendationer och vilka konsekvenser det skulle innebära och skulle komma att krävas då Barlastkonventionen träder i kraft. Resultatet visade att kostnaderna kommer att bli omfattande vid installation samt att det kommer att krävas teknologiska åtgärder. Vidare visade undersökningen att inköpskostnaden endast utgör en liten del av fartygets investering och att barlastreningsanläggningar är tämligen underhållsfria. / The task discussed the consequences within the ship’s operation (economical costs and technology) companies will be affected with when IMO’s Ballast Water Convention enters into force and ballast water has to be treated before entrance to the Baltic Sea. The purpose with the task was to find out which consequences companies will be forced with when IMO’s Ballast Water Convention enters into force. The result compares the difference between law and recommendation because HELCOM’s recommendations are based on IMO’s Ballast Water Convention’s laws. A qualitative method has been used, such as an open interview form, where four different companies were interviewed. The purpose with the interviews was to see if the companies followed HELCOM’s recommendations and which consequences it would lead to and would be necessary when the Ballast Water Convention enters into force. The results showed that the costs would be extensive when installation takes place and it will require technical arrangements. The task also shows that the purchase cost only makes a small part of the vessel’s investment and ballast water treatment systems are almost totally maintenance-free.