Renewables Coprocessing as Decarbonization Strategy – The Challenges of Green Diesel Production

Introduction and Context

???????????Despite the current trend of reduction of transportation fuels demand, some markets still present great dependence of these crude oil derivatives to sustain his economic development, this is especially true to in development economies like Brazil. The country is the seventh world largest crude oil derivative consumer, and a major part of this consumption is related with transportation fuels leading to the country reach the third position in this category, demanding mainly middle distillates (diesel and kerosene). Due to his continental dimensions and dependence of road transportation to supply his logistics necessities, the most consumed derivative in Brazil is the Diesel, Figure 1 present the Diesel sales in the Brazilian domestic market over the last years. According to most recent data, the sales of diesel in the Brazilian domestic market reach close to 990.000 barrels per day in 2019, a growing of 3,0 % in relation to the earlier period.

Figure 1 – Diesel Internal Demand in the Brazilian Market between 2007 and 2018 (Source: ANP, 2019)

Over the years, in face of the rising pollution levels associated with the technological development and the rise in petroleum consumption, the environment legislation has become increasingly severe.

???????????Restrictions on SOx and NOx emissions induced the necessity to higher technology development that can allow reducing the contaminants levels in the petroleum derivates, mainly sulphur and nitrogen. Normally, the concentration of contaminants increases with the density of the petroleum derivate, due to his characteristics and large consumption, Diesel was target of the most restrictive regulations over the years. Taking as example the Brazilian market again, over the last years the maximum sulfur content in marketable Diesel falls from 1.800 ppm to 10 ppm, this requires great capital investment from refiners to adapt the refining hardware to produce cleaner fuels.

???????????A lot of technologies were applied to reduce the contaminants levels in the petroleum derivates, for example, the kerosene treating with Clay, the adsorption of sulphur compounds over black carbon and the recognized treatments Bender and Merox. The mentioned technologies show limitations, mainly when the concentration of contaminants is high.

???????The hydrotreating technology (treatment with hydrogen) was studied by many researchers in the refining industry and academic sector over the decades and, currently, is practically impossible to attend the petroleum derivates specifications without these streams passing through the hydrotreating unit.?Despite the production of cleaner fossil fuels through hydroprocessing technologies, the society requires even more efforts from the crude oil processing industries aiming to minimize the environmental impact of his operations and products.

???????????In this environment, the co-processing of renewable raw material in conventional crude oil refineries appears like an alternative to produce low carbon transportation fuels, especially in high demand markets like Brazil. In these markets, the processing of renewable feeds with fossil diesel and kerosene can show a cleaner and profitable route.

Hydrotreating Technologies – General Overview

???????????The hydrotreating process involves a series of chemical reactions between hydrogen and organic compounds containing the contaminants (N, S, O, etc.). According to the target contaminant of the hydrotreating, the process can be called hydrodesulfurization (removing S), hydrodenitrogenation (removing N), hydrodeoxygenation (removing O) or hydrodearomatization when the main objective is to saturate of aromatic compounds, among others.

The most commons hydrotreating forms are hydrodesulfurization (where the objective is to remove compounds like benzothiophene, dibenzothiophene, etc.) and the hydrodenitrogenation (removing porphyrins, quinolines, etc.) These compounds, besides provoke emissions of SOx and NOx when are burned, produce in the derivates acidity, color and chemical instability.

The main chemical reactions associated with the hydrotreating process can be represented like below:

R-CH=CH2 + H2 → R-CH2-CH3 (Olefins Saturation)

R-SH + H2 → R-H + H2S (Hydrodesulfurization)

R-NH2 + H2 → R-H + NH3 (Hydrodenitrogenation)

R-OH + H2 → R-H + H2O (Hydrodeoxigenation)

Where R represents a hydrocarbon.

???????????The hydrotreating reactions are exothermic, and reactor temperature is controlled through injection of cold hydrogen between the catalyst beds.

???????????The hydrotreating process is normally conducted in fixed bed reactors and the most applied catalysts are Cobalt (Co), Nickel (Ni), Molybdenum (Mo) and Tungsten (W), commonly in association with then and supported in alumina (Al2O3). ?The association Co/Mo is applied in reactions that need lower reactional severity like hydrodesulfurization, while the catalyst Ni/Mo is normally applied in reactions that need higher severity, like hydrodenitrogenation and aromatics saturation. Due to the higher activity, the required catalyst volume is lower when Ni/Mo is applied.

???????????The hydrotreating is applied in the finishing of the final products like gasoline, diesel or kerosene or like intermediate step in the refining scheme in refineries to prepare feed charges to other processes like Residues Fluid Catalytic Cracking (RFCC) or Hydrocracking (HCC) where the main objective is to protect the catalyst applied in these processes.

???????????The basic process flow is similar to the various hydrotreating processes (hydrodesulfurization, hydrodenitrogenation, etc.), however, the process severity, determined by variables like hydrogen partial pressure, temperature and catalyst vary and the contaminants removal is affected.

The hydrotreatment process units are optimized aiming a equilibrium between cited operational variables, because chemical reactions are exothermic and the decontrolled raising in the temperature can affect negatively the reactional equilibrium besides it’s possible the sintering of the catalysts, to minimize this risk normally the hydrotreating reactors have points between the catalyst beds where are injected hydrogen in lower temperature (quench lines) to permit a better control of the reactor temperature.

??Figure 2 shows a typical arrangement for a hydrotreating process unit with a single separating vessel.?

Figure 2 – Basic Process Flow Diagram for Low Severity Hydrotreating Process Units

???????????The configuration with a single separating vessel is normally applied in lower severity units, like hydrodesulfurization units. This arrangement is possible in this case because under reduced pressures the difference between water and hydrocarbons properties is large and the separation process needs reducing contact areas, so a single vessel can realize the separation process. ?

Diesel Hydrotreating Units

???????????To comply with the new regulations, the Diesel production requires higher severity units. Normally the straight run Diesel is processing with unstable streams (Light Cycle Oil, Coke Gas Oil, etc.) in high severity units as presented in Figure 3, where is possible to remove nitrogen or aromatics saturation, the unit operates with two separating vessels.

The high severity is required once, in the special case of middle distillates like Diesel, the presence of contaminants like sulfide, tiophenes, and aromatics sulfur compounds like dibenzothiophenes is among the most difficult compounds to remove through hydrotreating. The hydrodesulfurization reactions are favored by higher temperatures, while the hydrodearomatization reactions are favored by higher hydrogen partial pressures, by this reason the performance of diesel hydrotreating units requires a good balance between these variables, especially to units processing streams from Fluid Catalytic Cracking units (FCC), like light cycle oil (LCO) that presents high aromaticity and high sulfur content.

???????????For higher severity units like Diesel hydrotreating, the difference between water and hydrocarbons properties is small and the phase separation process needs higher interface area so, two separating vessels are applied, one under high pressure where the separation among liquid and gaseous phase (H2, H2S, NH3 and light hydrocarbons) occurs and other under low pressure where the separation between aqueous and hydrocarbon phase is promoted, apart from the separation of the remaining gases.?Units with high severity operate under temperatures 330 to 380 oC and pressures varying from 40 to 120 bar. ?

Figure 3 – Basic Process Flow Diagram for High Severity Hydrotreating Process Units

Due to the stricter limit of sulfur content in the diesel (< 10 ppm), Ni/Mo is applied as catalyst to diesel hydrotreating units once this catalyst present higher activity to desulfurization reactions.

The principal process variables considered in diesel hydrotreating units is the total pressure, hydrogen partial pressure, make-up hydrogen purity, recycle gas rate, reactor temperature, and space velocity (liquid hourly velocity, LHSV). The space velocity defines the time required to achieve a desired performance of the reactions, this parameter can be defined as presented in equation 1.

LHSV (h-1) = Feed Rate (m3/h)/Catalyst Volume (m3)????(1)

The LHSV is a key parameter to hydrotreating units, not only to the design but also to the optimization of the unit once it’s possible to estimate the Start of Run (SOR) temperature and control the catalyst lifecycle based on the End of Run (EOR) temperature that is normally limited by the mechanical resistance of the material applied to reactors design. Typical diesel hydrotreating units present LSHV between 0,75 to 2,5 h-1. In some designs, especially for deep hydrodesulfurization units, the reaction section is separated in two stages with the removal of H2S and NH3 between the reaction stages aiming to minimize the deactivation effect of these gases over the catalyst, this can be especially attractive to hydrotreating units focused to produce ultra-low sulfur diesel (ULSD).

As aforementioned, Diesel is the crude oil derivative that had the most increasing demand in the last decades. This derivative is mainly applied as a transportation fuel by vehicles equipped with Diesel Cycle engines, is composed by hydrocarbons between C10 and C25 with a boiling range of 150 oC to 380 oC. The diesel ignition quality is measured through the Cetane Number that corresponds to a volumetric percentage of cetane (n-hexadecane) in a mixture with heptamethylnonane, burns with the same ignition quality of the analyzed diesel. ?The linear paraffinic hydrocarbons are the compounds that most contributes to the diesel ignition quality, raising the cetane number while the presence of aromatics reduce this parameter and prejudice the ignition quality, currently, the minimum cetane number of commercial diesel is 48.

Another important parameter controlled in the diesel is the plugging point that aims to control the content of linear paraffins that tends to crystallize under low temperatures prejudice the fuel supply to the engine. The plugging point is determined according to the weather conditions in the region of application, in Brazil the plugging point is controlled in the range of 0 to 10 oC, in colder regions the cold flow properties tends to be a significant concern to refiners, especially those processing light and paraffinic crudes like north American shale oils, in these cases the refiners normally install dewaxing beds in the hydrotreating reactors containing catalysts based on zeolites to promote the cracking of longer paraffin.

The Diesel emissions control is carried out managing the fuel density aiming to control the content of heavy compounds, especially polyaromatics. Currently, the density of commercial diesel is controlled in the range of 830 to 865 kg/m3, to ultra-low sulfur diesel (ULSD), this parameter is controlled below 850 kg/m3. In the last decades had been great efforts to reduce the environmental damage produced by the diesel burn, nowadays, the environmental regulations require the commercialization of low sulfur diesel with a maximum sulfur content of 10 ppm, despite in some markets mainly in developing countries still are commercialized diesel with higher sulfur content (500 ppm), but this tends to change in the near future.

Great efforts were employed in the hydrotreating technology development, however, technology licensors like Axens, UOP, Exxon Mobil, Lummus, Haldor Topsoe, Albemarle among others, still invest in research to improve the technology, mainly in the development of new arrangements that can minimize the hydrogen consumption (high cost raw material) and that apply lower cost catalysts and more resistant to deactivation process.

Renewable Co-processing in Diesel Hydrotreating Units

???????????Some refiners and technology licensors have been developed process technologies that make possible the higher synergy of renewable raw material with the conventional refining industry. Some examples are the technologies Esterfip-H? and Vegan? by Axens Company that allow the production of Diesel and Jet Fuel from renewable raw material, beyond these technologies the process Gasel? also from Axens Company applies renewable raw material and Fischer-Tropsch route to produce transportation fuels.??The UOP Company developed the technologies Green Diesel? and Green Jet Fuel? as presented in Figure 4.?

Figure 4 –Green Jet Fuel? Process by UOP Company

???????????Among the remain technologies dedicated to the processing of renewables feedstreams, we can quote the Hydroflex? process by Haldor Topsoe Company and the process IH2? by Shell Company.

???????????In the petrochemical sector, the production of petrochemical intermediates also has been adopted renewables processing routes as ethanol to produce ethylene. The Braskem Company has been applied the ethylene production through ethanol dehydration since 2010 and the Technip Company commercializes the Hummingbird? technology also dedicated to producing ethylene from ethanol.

???????????Despite the advantages of environmental footprint reduction of the refining industry operations, renewables processing presents some technological challenges to refiners. Figure 5 presents the chemical mechanism for the processing of vegetable/animal oils in hydrotreating units.?

Figure 5 – Chemical Mechanism of the Renewable Feedstream Hydrotreating (Article by ExxonMobil Company, 2011)

The renewable streams have a great number of unsaturations and oxygen in his molecules which lead to high heat release rates and high hydrogen consumption, this fact leads to the necessity of higher capacity of heat removal from hydrotreating reactors aiming to avoid damage to the catalysts. The main chemical reactions associated with the renewable streams hydrotreating process can be represented as below:

R-CH=CH2 + H2 → R-CH2-CH3 (Olefins Saturation)

R-OH + H2 → R-H + H2O (Hydrodeoxigenation)

Where R represents a hydrocarbon.

These characteristics lead to the necessity of higher hydrogen production capacity by the refiners as well as quenching systems of hydrotreating reactors more robust or, in some cases, the reduction of processing capacity to absorb the renewable streams. In this point it’s important to consider a viability analysis related to the use of renewables in the crude oil refineries once the higher necessity of hydrogen generation implies in higher CO2 emissions through the natural gas reforming process that is the most applied process to produce hydrogen in commercial scale. ?

CH4 + H2O = CO + 3H2????(Steam Reforming Reaction - Endothermic)

CO + H2O = CO2 + H2??????(Shift Reaction - Exothermic)

Figure 6 shows the evolution of hydrogen demand in the last years, in the refining industry, the growing demand is strictly related to the improvement of hydroprocessing capacity by the refiners aiming to meet the environmental regulations.

Figure 6 – Global Demand by Hydrogen in the Last Years (International Energy Agency – IEA)

???????????Despite the concern related to the CO2 emissions due to hydrogen production there are some cleaner hydrogen production routes that present attractive alternatives to the downstream players like the steam reforming of biomethane, reverse water gas shift (RWGS), and the electrolysis process.

The Challenge of Cleaner Hydrogen Sources

This fact leads some technology licensors to dedicate his efforts to look for alternative routes for hydrogen production in large scale in a more sustainable manner. Some alternatives pointed can offer promising advantages:

·??????Natural Gas Steam Reforming with Carbon Capture – The carbon capture technology and cost can be limiting factor among refiners;

·??????Natural Gas Steam Reforming applying biogas – The main difficult in this alternative is a reliable source of biogas as well as their cost.;

·??????Reverse water gas shift reaction (CO2 = H2 + CO) – One of the most attractive technology, mainly to produce renewable syngas;

·??????Electrolysis – The technology is one of the more promising to the near future.

Figure 7 presents a processing scheme to produce hydrocarbons applying renewable hydrogen, based in the Roland Berger Company concept.

Figure 7 – Hydrocarbons Production Routes Applying Renewable Hydrogen (Roland Berger Company, 2020).

As aforementioned, hydrogen is a key enabler to the future of the downstream industry and the development of renewable sources of hydrogen is fundamental to the success of the efforts to the energy transition to a lower carbon profile.

Hydrogen Network and Management Actions

???????????As mentioned above, the hydrogen became a fundamental production input to modern crude oil refineries and his adequate management is a key factor to ensure controlled operating costs and competitiveness in the market, as well as allow the production of marketable crude oil derivatives. The hydrogen management actions start with a mass balance involving the hydrogen network that is composed by hydrogen sources, hydrogen purification systems, and the hydrogen consumers as presented in Figure 8.

Figure 8 – A Typical Hydrogen Network in a Crude Oil Refinery

The hydrogen generation relies on the refining configuration adopted in the refinery. Normally, refineries that rely on Catalytic Reforming units apply the hydrogen produced in this process unit to compose a relevant part of the hydrogen network becoming an important internal source of hydrogen. As presented above the hydrogen generation route most applied in the refining industry is the steam reforming based on naphtha or natural gas.

The hydrogen purifying technologies is another important part of hydrogen network, normally the modern refineries apply Pressure Swing Adsorption (PSA) technologies to purify the hydrogen, reaching purity higher than 99 %. Despite this fact some refiners still use treatments based on amine treatment, as depicted in Figure 9.?

Figure 9 – Typical Amine Treating Unit

Despite the lower capital cost requirement when compared with PSA technologies, the amine treating units produce hydrogen with low purity and this represent great disadvantage, especially to refiners with deep conversion hydroprocessing units. Another hydrogen purifying technologies commercially available are the membrane separations that can reach purity of 98 % and the cryogenic processes that can reach 96 % of purity. The hydrogen purifiers have a key role in the hydrogen management once control the hydrogen recovery in off-gases, one of the main sources of hydrogen losses in the refineries is the burn as fuel gas during poor recovery capacity.

The high cost of hydrogen generation as well as the great amount of CO2 (Greenhouse gas) produced is the main driving force to an adequate hydrogen management in the refining hardware. Process integration technologies like pinch method and mathematical modeling are being applied to reach a most rational use of hydrogen in the refining hardwares.

The reliability of hydrogen purification systems as well as the optimization of hydroprocessing units is fundamental to avoid the burn of hydrogen in the fuel gas ring or flare that can raise the operating costs and reduce the refining margins of the refiners. Another key point is the availability of control and instrumentation systems to allow the flow measurement and adequate accuracy of mass balances and actions to define optimization actions and mathematical modeling.

The Role of Catalytic Reforming Units in the Refineries Hydrogen Balance

As aforementioned, demand for hydrogen raised strongly in the last decades following the necessity of hydrotreatment units installations in refineries to comply with the pressure to reduce the content of contaminants like sulfur and nitrogen in the petroleum derivates and consequently minimizing the environmental impact caused by fuels burn. This scenario became the hydrogen one of the most important production input in modern refineries and adequate hydrogen management actions reach strategic character to keep under control the operating costs and refining margins, contributing to economic sustainability in the downstream industry.

???????????Normally, refineries that rely on Catalytic Reforming units apply the hydrogen produced in this process unit to compose a relevant part of the hydrogen network becoming an important internal source of hydrogen. In some markets, where the demand by petrochemicals is lower, the main relevance of the catalytic reforming to the refining hardware is the hydrogen generation against the production of light aromatics. Figure 10 presents an example of hydrogen network in a crude oil refinery with high hydroprocessing capacity.

Figure 10 – Example of Hydrogen Network to a Crude Oil Refinery (LAFLEUR, 2017)

???????????In refineries with bottlenecked hydrogen generation units, the hydrogen from catalytic reforming units is fundamental to ensure the compliance with the current quality and environmental regulations, becoming a fundamental enabler to profitable and reliable operations of the refining hardware.

???????????Another challenge associated with renewables processing is the cold start characteristics of the derivatives, mainly Diesel and Jet Fuel. The renewable feed streams produce highly paraffinic derivatives after hydrotreating step as described in Figure 5, in this sense, the final derivative tends to show a higher cloud point which can be a severe restriction in colder markets as the northern hemisphere. ?

???????????In these markets, refiners tend to apply catalytic beds containing dewaxing catalysts (ZSM-5) in his hydrotreating units or cloud point depressors additives which can raise the operation costs.

As a case study, the Brazilian refining market has a demand of 2,3 million barrels per day from derivatives being the seventh crude oil derivatives consumer in the world and the third consumer of transportation fuels, from this volume, close to 550 thousand barrels are supplied by renewable fuels, mainly biodiesel and ethanol.?Figure 11 presents the monthly production of biodiesel in the Brazilian market in 2019.

Figure 11 – Monthly Biodiesel Production in the Brazilian Market (ANP, 2020)

???????????By the Law, the Diesel commercialized in Brazil should contain at least 12 % in volume of biodiesel and the gasoline should contain 27 % of ethanol which ensures the renewables participation in the Brazilian energetic matrix. Figure 12 presents the evolution of ethanol production in the Brazilian domestic market.

Figure 12 – Evolution of Ethanol Production in the Brazilian Market (ANP, 2020)

In the Brazilian case, the refineries don’t process renewables feed streams currently, the mixture of renewable fuels and fossil fuels is carried out by the distributors. Despite this, in 2020 the Brazilian Oil State Company, Petrobras start some tests in his refineries processing vegetable oil with fossil diesel in hydrotreating units, this route is capable to produce biokerosene that present great interest from the consumers due to the current pressure over the aviation sector to reduce the greenhouse gases emissions from his operations.

???????????Face the current decarbonization trend of the global energetic matrix, the governments tend to offer tax breaks to refiners that raise the participation of renewables in the crude oil refineries feedstocks or even the blending of renewable fuels with fossil fuels as in the Brazilian market. According to the marketing scenario, the adoption of renewables processing technologies can be economically attractive both to the production of transportation fuels and petrochemical intermediates as quoted earlier. ?

The Hydrotreated Vegetable Oil (HVO) – An Attractive Route to Reach “Green Diesel”

???????????As presented above, the necessity to build a continuous supply of more sustainable transportation fuels are leading the refiners to consider processing renewables raw materials in the refining hardware to achieve cleaner and less carbon fuels. One of the most promising initiatives in this sense in the production of Hydrotreated Vegetable Oil (HVO) to compose the Diesel pool of some refineries, the process consists of in processing renewable material like palm oil in conventional diesel hydrotreating units to produce the called “green diesel”. At this point it’s interesting to make a differentiation between the Biodiesel and HVO, the biodiesel is produced through the transesterification, producing a mixture of fatty acids and methyl esters, the HVO basically composed by normal paraffin which is result of hydrotreating reactions. The great advantage of the HVO in comparison with the biodiesel is the similarity of properties in relation with the fossil diesel, the density of the HVO tends to be lower than the fossil diesel and cetane number tends to be high, being a perfect additive in a final mixture, in the other side the high concentration of normal paraffin lead to a worse cold flow characteristics, which can be bypassed through the use of dewaxing beds in hydrotreating reactors applying ZSM-5 catalysts to control the dimension of paraffin chain, due to these characteristics the HVO can be a better blending agent to the final diesel than the traditional biodiesel produced by transesterification.

???????????One of the most challenge of the HVO production is the cost of raw material as well as the choice of this raw material. Another great challenges to the HVO production in the traditional crude oil refineries is the catalyst applied in the process, normally the hydrotreating catalysts are composed by metal sulfide like NiMo or CoMo carried over Alumina, but the low sulfur concentration and the water production during the hydrotreating reaction of renewable raw materials tends to deactivate these catalysts. An alternative in this case is to feed H2S with the feed stream, but there is always the risk to contaminates the final derivative with high sulfur content, the use of noblest metal like Ru and Pt as active metal can solve this problem, but the operating cos can be prohibitive.

???????????Another challenge related to the HVO production is the higher heat release in the hydrotreating reactors which requires a well dimensioned quenching systems, it’s important to remember that the conventional hydroprocessing reactors are designed to deal with low contaminants concentration while the renewables raw materials present high quantity of unsaturated molecules and oxygen, leading to a high heat release rate.

???????????Another issue related with the coprocessing of renewables raw material in crude oil refineries is the tendency of water retention in the final derivatives. Due to the chemical structure, the biodiesel for example, tends to retain more than 8 times more moisture than fossil diesel which can lead to issues like microbiological degradation of the fuel in the transport and storage systems. The soluble water content in pure biodiesel can reach close to 1.800 ppm while the value to the diesel with 20 % of biodiesel can reach close to 280 ppm of soluble water, and the diesel with 5 % of biodiesel can present until 150 ppm, this fact will lead the refiners to adequate their hardware to allow the water removal from the final derivatives applying draining systems or the application of salt filters to control the moisture content in the final derivatives.

From the point of view of crude oil producers, the renewables coprocessing can be faced as a demand destruction. This threat can be overcome through enjoying the change in the profile of crude oil consumption where is observed a growing demand by petrochemicals intermediates like ethylene, propylene, and BTX while the transportation fuels like gasoline and diesel present falling demand.

Conclusion

???????????The hydroprocessing technologies became fundamental to the crude oil refining industry in the last years, once is practically impossible to produce marketable crude oil derivatives without at least one hydroprocessing step. The diesel hydrotreating units are especially relevant to refiners inserted in high demand by transportation fuels like Brazil, in these markets, the hydroprocessing capacity in a key factor to ensure economic operations and competitiveness to refiners as well as compliance with market demand and environmental regulations. The co-processing of renewable raw materials in diesel hydrotreating can allows a significant reduction in the environmental impact of the final fuel, especially related to greenhouse gases emissions, although present some technologic challenges to the refiners like the higher hydrogen consumption, and the cold start requirements of the final derivatives that can be an important issue in colder regions, despite these points, the energy transition is a great demand and the pressure over the refiners tends to grow in the next years aiming to produce cleaner fuels through cleaner processing routes. In this scenario, the renewable co-processing with fossil streams offers an attractive alternative to refiners.

???????????It’s important to consider that the energy transition is a reality nowadays. In August of 2020, Phillips 66 that is a great player in the downstream industry announces the conversion of a crude oil refinery (capacity of 120.000 barrels/d) to a renewable processing plant. The energy transition needs to be a value to any player of the downstream industry, of course, respecting the restrictions and maturity of each local market. Another key question to the energy transition is the hydrogen source, the hydroprocessing technologies became fundamental to the downstream industry both to produce high quality and cleaner derivatives or to prepare feedstocks to the processing units like residue fluid catalytic cracking and this dependence raised, even more after the start of IMO 2020 that requires a deep treatment of bottom barrel streams aiming to comply with the new quality requirements of the marine fuel oil (Bunker). In this sense, the hydrogen generation units achieve strategic character to refiners and the efficient and reliable operation of these units needs to be a priority to refiners.

Beyond the current status, it’s important to understand that the energy transition is no longer a choice matter to the players of the downstream industry, but a reality, and the efforts to find cleaner sources of hydrogen needs to be supported to refiners aiming to minimize the environmental impact of crude oil processing chain at the same time to ensure the production of high quality and added value derivatives.

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