The design of the Ultrasonic- Aquaprocessing Upgrading Plant is divided into four zones: Feeding and ultrasonic reaction zone, the first section of heating and separation zone, the aquaprocessing reaction zone and the final separation zone. The final product is an upgraded heavy fuel oil with a lower viscosity value and with a maximum sulfur content of 0.5%. Outside of desulphurization, it is also important to note that our process can help reduce sediments through filtration step introduced prior to the feedstock being processed.
Ultrasonication provides an optimal reactive environment, when combined with oxidants that oxidize the sulphur compounds in the oil phase faster and completely with high selectivity to sulfones and sulfoxides, with minor oxidation of other components of the fuel oil. The water-soluble catalyst used in the process further supports the oxidation process.
While the desulphurization of HSFO can reduce the sulphur content to as low as 0.5% in hydro-treating processes, it is by brute force of increasing severity conditions such as operating pressure and temperature, residence time, etc. . Conventional hydro-treating processes also require large quantities of hydrogen to extract the sulphur, which produces additional CO2. All these factors cause the desulphurization of HSFO to require significant additional investment and operating costs of the process resulting in it being unsustainable for a continuous long term process.
Conversely, the heterogeneous catalyst designed for the IUT Ultrasonic assisted ODS process generates its own hydrogen, thus eliminating the need for externally sourced/expensive hydrogen off sites.
This new (IUT second generation) configuration provides a much better use of the hydrogen generated in the AQP stage, which can now be used for hydrogenation/hydrotreating; it also uppers the limits of the AQP stage in terms of conversion and quality since the hydrogenation treatment will reduce sulfur and aromatics, creating new sigma bonds susceptible of cracking under the AQP stage, and most probably will increase the process lifecycles of the catalyst and its final durability. It will also increase the investment costs, however adding relatively minor costs compared to conventional and mostly thermal, thus energy-inefficient, partial upgrading processes.
The novelty of AQP consists of the nascent (in reactor) production of hydrogen for upgrading from steam, operating at low pressure (one-third of typical hydrotreating operations) and moderate temperature in a fixed bed catalytic reactor that performs partial upgrading. The reactions that take place eliminates the previously oxidized sulfur in the oil (sulfones), to comply with the sulfur new regulations for maritime fuel oil, and also eliminates naphthenic acidity, opposite to the dilution process that only reduces it. Therefore, the full corrosive power of these oils reveals back at the refineries once the diluent has been separated. Furthermore, the thermo-catalytic hydro-steam processing reactions occurring in AQP simultaneously reduces the viscosity above 99% with no production of olefins.