Optimization of Offshore De-oiling Hydrocyclone Performance: Plant-wide Control and Real-time OiW Measurement

One of the biggest environmental concerns in offshore oil & gas production is the quality of tremendous amounts of produced water discharged into the oceans. Today, in average three barrels of water are produced along with each barrel of oil [9]. This concern will become more severe in the future, along with the facts that the global oil demand will continuously grow by 7 mb/d to 2020 and exceed 99 mb/d in 2035, meanwhile, many production fields turn to be matured and thereby the water flooding technology is more and more employed as a key enhanced oil recovery solution for these fields [9]. Fig.1 Classification of typical offshore PWT technologies in terms of performance vs. cost [12] As shown in Fig.1, the offshore PWT technologies are classified into four categories according to their purification performance and relevant expenses [12]. Apparently, almost 90% of offshore PWT facilities are based on the hydrocyclone technology, due to the fact that it is one of the cheapest and most reliable solution with a best performance to 20 ppm (mg/l) [9,13]. In 2013, under the partial support from the Danish Advanced Technology Fund (now called Innovation Fund), the AAU together with two Danish OG companies, Maersk Oil and Ramboll Oil & Gas A/S, launched a research project HTF-PDPWAC with total budget of 10 million dkk. One of the focuses of this project is to optimization of the de-oiling hydrocyclone performance in order to improve the produced water treatment quality without sacrificing the capacity.