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RESUMO -The drilling fluids most commonly used in oil and gas drilling operations are synthetic fluids with low biodegradability. These fluids contaminate the drill cuttings, which must undergo decontamination before disposal. Microwave drying has been investigated as a remediation technique for drill cuttings. The objective of this work is update the industry with experimental results of a novel cuttings drying technology based on microwave heating. The expectation is to provide a competitive technology for offshore applications. The motivation is to provide alternatives for efficient cuttings drying to reduce the environmental impact of offshore drilling operations. A semi industrial continuous microwave dryer was initially built to process oily cuttings at flow rates around 0.5 ton/hr. Construction parameters were based on extensive lab scale experiments previously and preliminary tests. Real cuttings and internal olefin based drilling fluids were used. A low field RMN technology was used to evaluate oil contents in inflow and outflow samples. Initial content of synthetic base on the drill cuttings, feed flow rate, residual content and specific energy were some of the variables investigated. Results obtained from preliminary tests and a 9 experiment test matrix show that the technology is able to reduce oil concentration in cuttings to values as low as 0.1% depending on operational parameters. The operational limits of the equipment were successfully pushed to allow processing a cuttings flow rate of 0.75 ton/h. The specific energy of this equipment proved to be competitive with other commercial equipment. The present experimental campaign encourages the continuation of the project signalizing for studies to allow the construction of a field scale microwave cuttings dryer to operate either at a floating rig or at a dedicated ship that would be able to process cuttings generated by several neighbor drilling vessels.

Real-time drilling data is an essential tool to increase performance and operational safety, especially when operating in challenging environments. In this scenario, it is highly attractive to use new tools that can anticipate possible risks to the operation, aiding in decision making in order to guarantee operational efficiency and safety. The present work aims to present the new technologies developed in a real-time monitoring software (GANDELMAN ET AL., 2013), which automatic diagnosis drilling problem, from the calculations of loads alongthe drill string and the contact of the column with the borehole wall. Torque and drag models are used to support well planning. The aim is to ensure the feasibility of theoperation and to assist in the prediction and prevention of operational problems during drilling. Directional wells require even more attention, since, as their inclination increases, additional forces are observed due to the enhanced contact of the drill string with the borehole wall. Since these forces are cumulative, the deeper the well, the larger will be the contact forces and, consequently, the torque and drag values. A comprehensive torque and drag model was implemented to estimate the wear level on the casing, in real-time, due its contact with the drillstring. The purpose of this development is to automatically warn when the calculated wear approaches the expected and / or permitted wear. Still using the T&D model implemented in the real-time monitoring software (GANDELMAN ET AL., 2013), a module was developed for a more accurate detection of the tubular element that is passing through each of the BOP (blowout preventer) rams when drilling from floating vessels. The main objective of this new technology is to assist the operation in a possible emergency disconnection. The main focus would be to precisely define the moment to actuate a RAM, minimizing the risk of reaching a non-shearable component of the drillstring. Therefore, a logic of tracking each element of the column in front of the BOP rams was created, which takes into account the effect of axial elongation due to real-time tension and compression.