Oil and gas platforms with steam bottoming cycles: System integration and thermoenvironomic evaluation

Highlights: • The energy demand of a North Sea platform is systematically analysed. • The integration of steam bottoming cycles is investigated, considering energy, economic and environmental criteria. • The fuel gas consumption and total CO₂-emissions can be reduced by more than 15%. - Abstract: The integration of steam bottoming cycles on oil and gas platforms is currently regarded as the most promising option for improving the performance of these energy-intensive systems. In this paper, a North Sea platform is taken as case study, and a systematic analysis of its energy requirements is conducted. The site-scale integration of steam networks is evaluated, based on thermodynamic, economic and environmental performance indicators. The penalties induced by operational restrictions such as (i) the use of a heat transfer loop, (ii) the demand for a heat buffer, (iii) the selection of a specific cooling utility, and (iv) the weight limitations on the platform are quantitatively assessed. The results illustrate the benefits of converting the gas turbine process into a combined cycle, since the fuel gas consumption and the total CO₂-emissions can be reduced by more than 15%. Using the cooling water from the processing plant reveals to be more profitable than using seawater, as the additional pumping power outweighs the benefit of using a cooling medium at a temperature of about 8 °C lower. This study highlights thereby the importance of analysing energy savings and recovery options at the scale of the entire platform, rather than at the level of the utility plant solely