Evaluation of Radio Frequency Heating and Microwave Radiation for Treatment of Oil Contaminated Drill Cuttings

Abstract

Current market challenges make the improvement in drill cuttings treatment technology necessary. Oil companies strive towards robust and environmental friendly treatment solution that allow for high treatment capacity and oil separation. The Thermtech cutting cleaner (TCC) is the only accepted technology for treatment and discharge of OBF contaminated cuttings on the Norwegian Continental Shelf (NCS). Offshore treatment of drill cuttings would likely yield considerable cost savings. Norwegian Technology AS (NT) has recently developed a new concept to treat OBF contaminated cuttings. NT’s technology relies on microwave heating with advances in process temperature and energy requirements. As a result, a more robust system yielding higher oil separation and treatment capacity can be achieved. The objective of this thesis is to evaluate radiofrequency heating as heat source for pre and main treatment. Microwave radiation with low power density in a multimode cavity system is also investigated. Based on research and indication experiments, RF was found to serve great potential to be combined with NT new technology development for drill cuttings treatment. RF is favourable over MW due to high power input, which will decrease the energy consumption, hence less footprint and cost connected to it. RF is also favourable in regards to safety. In the pretreatment experiment, sufficient dewatering was achieved, with minor oil separation. Significant oil separation was achieved in the main treatment setup with low power density in a multimode microwave cavity. The drill cuttings were treated to 0,44 % water and 7,78 % OOC in the pre-treatment setup, and 0,18% OOC after main treatment. The new treatment technology serve great potential and can challenge more established treatment technologies.