Decarbonization has entered all lines including the air transportation sector. Aviation fuel must also gradually shift from fossil fuels to sustainable renewable fuels. However, decarbonization in this sector is still slow, namely currently only around 0.01% of the use of sustainable renewable fuels or SAF (Sustainable Aviation Fuel) globally for these aircraft. These barriers include technological maturity or technological readiness, certification for SAF conversion or production process routes, scale up and commercialization, price gaps with fossil fuels, and competition with biofuels in the land transportation sector. The Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA) has initiated a reduction in GHG emissions for global aviation. Using the 2019 baseline, it is estimated that around 2.5 billion tonnes of CO2 emissions need to be offset / reduced in the 2021-2035 period to achieve carbon neutral growth. CORSIA also plans its implementation in three phases, namely the pilot phase in 2021-2023, the first phase in 2024-2026 and the second phase in 2027-2035. Participation of member countries is voluntary in the first two phases (2021-2026) and mandatory in the 2027 phase and beyond, except for the least developed countries, small developing countries and landlocked countries.
Until now, HVO / HEFA - SPK (Hydro-processed Esters and Fatty Acids-Synthesized paraffinic kerosene) technology using vegetable oil including waste oil is the only technology that is most ready for the conversion or production of SAF. Currently, the technology readiness level (TRL) and feedstock readiness level (FRL) are at level 9, meaning that it is the most ready among other conversion technology routes. One of the advantages of HVO technology is the flexibility of using various feedstocks / raw materials so that waste oil such as PAO or mico from palm oil mill ponds and also used cooking oil or used cooking oil or UCO are also very potential to be converted into SAF with HVO technology. But in fact, even though HVO technology can directly produce SAF, most of the HVO technology is used for the production of diesel engine fuel for land transportation or commonly called green diesel or renewable diesel. Green diesel or renewable diesel is different from biodiesel or FAME-based biodiesel which is produced by the transesterification process. And green diesel or renewable diesel from HVO also has a number of advantages compared to FAME based biodiesel.
HVO production is also not a new technology. Globally, there are a number of large-capacity commercial HVO plants that use vegetable oil as raw material. The largest plants are Neste in Rotterdam and Singapore with a capacity of 1.28 billion liters per year and Diamond Green Diesel in Louisiana with a capacity of 1.04 billion liters per year. HVO production is closer to petroleum refining technology than conventional diesel production. This is why oil and gas companies may be more interested in developing it than palm oil companies or conventional biodiesel companies. Palm oil mills have raw materials / feedstock, while oil and gas companies may be more relevant to downstream development because of the readiness to adapt technology and develop end products.
HVO is produced by hydrogenation and hydrocracking of vegetable oils and animal fats using hydrogen and catalysts at high temperature and pressure. In this hydrotreating process, oxygen is released from the feedstock consisting of triglycerides and / or fatty acids. This will produce straight chain hydrocarbons (paraffins) with various properties and molecular sizes depending on the characteristics of the raw materials and the operating conditions of the process being carried out. This conversion usually goes through two stages, namely hydrotreatment followed by hydrocracking / isomerization. This hydrotreatment process is usually carried out at a temperature of 300 -390 C and for triglyceride treatment, propane is usually produced as a by-product. The final product of straight chain hydrocarbons can be adjusted according to certain fuel types such as bio jet fuel or SAF. Currently HVO is the third most common biofuel in the world after ethanol and FAME based biodiesel.
PAO is produced as waste or by-product of palm oil mills. PAO will always be produced because palm oil mills cannot have an efficiency level of 100% and the less efficient the palm oil mill, the more oil becomes waste or by-product in the form of PAO. It is estimated that there are currently 1 million tons of PAO in Indonesia and 0.5 million liters in Malaysia or a total of 1.5 million tons. As for UCO or used cooking oil with the use of cooking oil reaching 1.55 million tons/year assuming 10% can be recovered as used cooking oil or UCO, 155 thousand tons/year are produced. In addition to being part of the effort to overcome waste both in palm oil mills and households that pollute the environment, the production of SAF or bio-jet fuel has also contributed to the decarbonization of the air transportation sector. With HVO / HEFA technology that is able to process waste oil such as PAO and UCO, the more PAO and UCO that can be processed, the better.
No comments:
Post a Comment