| dc.description.abstract | The demand for petroleum is still increasing. As a result, various wastes are generated during exploration and production, even though strict rules and regulations are applied to oil and gas industries to optimize waste management programs. The refineries still produce significant amounts of crude oil sludges formed at the bottom of crude oil storage tanks. This waste is identified as hazardous waste. The accumulation of crude oil sludges negatively impacts the storage capacity and the safe operation of the storage tanks.
This study presents the problem connected with crude oil sludges and the alternatives for its treatment. In favor of minimizing the environmental impact caused by oil sludges, the primary strategy for its treatment is to separate the sludge into its main components: oil, water, and solids. The oil in the sludge may be considered a recovery source. The sludge´s complex composition and properties were comprehensively described on how to separate the sludge. A method for destabilizing and separating the sludge into three phases was proposed and tested on two types of sludges (Mongstad sludge and Brenda sludge).
Chemical destabilization of crude oil sludges by adding different MudSplit chemicals followed by centrifugation proved to give a positive result. The results showed how variables in sludge composition and properties challenge the treatment process of this waste. Temperature and pH were enhancing factors for Mongstad sludge's destabilization. Heat energy reduced the viscosity of the sludge, and the addition of MudSplit chemicals also reduced the viscosity. Mongstad sludge gave three-phase separation, where in most samples, the upper phase contained >90 % oil and was free of water. The effect of the tested MudSplit chemicals was not comprehensively observed under the different experimental conditions. Brenda sludge showed to be more difficult to destabilize. It was possible to separate the sludge into three distinct phases through chemical and mechanical treatment. The best results for Brenda sludge were recorded using MudSplit6. | |
