From industrial manufacturing and metal processing there emerges quite a big amount of oil-contaminated wastewater meaning a big threat to the environment as well as to the drinking water supply. Nature has its difficulties in reducing these long-chained hydrocarbon-based chemical compositions, which can lead to enduring environmental damages. Generally speaking oil/water mixtures cannot be treated via membrane filtration processes - unless oil and water form a so called emulsion. Emulsions are disperse systems combining two non-mixable liquids to an optical entity. For emulsion separation and thus for lifetime enhancement of degreasing baths, T-CUT tubular modules proved to work very efficiently.