Production and processing of sour crude and natural gas - challenges due to increasing stringent regulations

The worldwide demand for petroleum is growing tremendously. It is expected that the demand will have incremental capacity of 20 mb/d for crude oil, reaching 107.3 mb/d, and demand for natural gas will rise nearly 50% to 190 tcf in 2035, compared to 130 tcf now. According to the International Energy Agency 70% of crude oil reserves and 40% of natural gas reserves are defined as having high content of organosulfur compounds. Obviously, for decades to come, to satisfy the growing global needs for fossil fuels, reservoirs with sour contaminants will be developed intensively. The sulfur compounds in crude oils and natural gas generally exist in the form of free sulfur, hydrogen sulfide, thiols, sulfides, disulfides, and thiophenes. These compounds can cause considerable technical, environmental, economic, and safety challenges in all segments of petroleum industry, from upstream, through midstream to downstream. Currently, the sulfur level in on-road and off-road gasoline and diesel is limited to 10 and 15 ppm respectively by weight in developed countries of EU and USA, but this trend is now increasingly being adopted in the developing world too. Furthermore, it has to be expected that the sulfur level requirements will become more and more strict in the foreseeable future, approaching zero sulfur emissions from burned fuels. The production of ultra low sulfur automotive fuels has gained enormous interest in the scientific community worldwide. Oxidative desulphurization, biocatalytic desulphurization, and combined technologies, which are alternatives to conventional hydrodesulphurization technology, are much more efficient and more economical in removing complex sulfur compounds, especially benzothiophene, dibenzothiophene and their alkyl derivatives