Thermal treatment of drill cuttings

Master's thesis in Environmental technologyIncreased environmental stringency, and focus on cost efficiency, drives the oil & gas industry towards new and better solutions. Members of OSPAR have to follow strict discharge requirements for oil contaminated drill cuttings, based on the BAT, and BEP principles. The most successful technologies rely on thermal desorption. Only the TCC have received acceptance to treat and discharge OBM cuttings on the NCS, at a requirement of 0.05 % oil by weight. Norwegian-Group AS is currently developing an integrated treatment solution for drilling fluids, waste water, and cuttings. In this thesis, thermal treatment of cuttings is investigated. The treatment concept rely on dielectric heating with microwaves, in combination with environmentally friendly, polar organic compounds. The initial study shows that glycols can be distilled without significant degradation, especially MEG. In addition to the benefits of increased process temperature, a significant reduction in energy requirement is possible. The energy required to vaporize MEG is in the order of magnitudes lower, than what is required to vaporize water. Due to a higher process temperature , the vapor pressure contribution from the oil was significantly increased. Drill cuttings was successfully treated to well below the OSPAR limit of 1 % oil by weight, by the use of susceptors. The presence of susceptors significantly increased the oil separation from cuttings, especially when the cuttings did not contain water. It is believed that the use of susceptors in combination with microwaves can challenge the TCC technology as BAT