Alternative Fuel Handling HVO GTL and Synthetic Fuels

As we navigate the changing landscape of energy consumption, the need for alternative fuels is becoming more pressing. This article seeks to explore this vast topic. It focuses on specific types of fuels:  

Hydrotreated Vegetable Oil (HVO)

Gas-to-Liquids (GTL)

Synthetic Fuels

We will explore the fundamental characteristics of these fuels and discuss whether they contain solid particles, factors crucial in understanding their handling and storing requirements.  

In addition, we will look into the types of pumps best suited for these alternative fuels and determine whether there's a need for ATEX-certified equipment in their handling. To further deepen our understanding, we will dissect what exactly HVO, GTL, and Synthetic Fuels are, their sources, and their comparison in terms of benefits and drawbacks. Finally, we will touch upon the critical aspect of their cost comparison with conventional fuels like Diesel and Petrol. 

What are Alternative Fuels? 

Alternative fuels, such as HVO, GTL, and Synthetic Fuels, diverge from traditional fossil fuels like petroleum, coal, and natural gas. They serve as less carbon-intensive energy substitutes and help lower carbon and non-carbon emissions, including nitric oxide, nitrogen dioxide, sulfur dioxide, and other harmful gases in different sectors like mining, where toxic gases accumulate.  

Proponents highlight their environmental benefits, potential long-term cost savings, health benefits, reduction of air pollution, and decreased dependence on foreign energy sources. However, critics point out the significant initial costs, uncertainty about their reliability, and potential negative impact on agriculture, as some alternative fuels are derived from crops. 

What exactly are HVO, GTL, and Synthetic Fuels? 

Hydroprocessed Vegetable Oil (HVO), Gas-to-Liquids (GTL), and synthetic fuels are all advanced fuel technologies that generate cleaner-burning fuels from diverse raw materials.  

• HVO is a type of renewable diesel fuel. It's created through a process where vegetable oils or animal fats are subjected to hydrogenation, which prompts a high-quality fuel that can be used in a conventional diesel engine without modification. 

• GTL technology involves converting natural gas or other gaseous hydrocarbons into longer-chain hydrocarbons (gasoline or diesel fuel) via Fischer-Tropsch synthesis. The feedstock for GTL is primarily natural gas, an abundant resource in the world.  

• More broadly, synthetic fuels can be derived from any carbon-based feedstock, including coal, natural gas, biomass, or even carbon dioxide. The specific properties of the synthetic fuel are determined by the choice of feedstock and the production process used. 

What are Their Typical Viscosities? 

Alternative fuels come with varied viscosities that can pointedly impact their transport, storage, and injection into combustion systems. The viscosity of alternative fuels can range from very low, similar to light distillates, to very high, akin to residual fuels, based on the specific fuel type and its processing. Also, the viscosity influences atomization and spray characteristics during combustion. It's a crucial parameter for fuel handling and combustion optimization. 

• Hydrotreated Vegetable Oil (HVO): HVO, a type of renewable diesel, typically exhibits viscosities of 2.4 to 2.8 mm²/s at 40°C. This viscosity is due to its paraffinic nature, which results from the hydrotreatment process that removes impurities and oxygenates. 

• Gas-to-Liquids (GTL): GTL fuels, produced by converting natural gas into longer-chain hydrocarbons, generally display viscosities around 0.6 to 1 mm²/s at 40°C. It stems from the Fischer-Tropsch synthesis process yielding predominantly paraffinic compounds. 

• Synthetic Fuels: The viscosity of synthetic fuels can vary depending on their feedstocks and production processes (Fischer-Tropsch, coal liquefaction, or biofuel synthesis). Thus, synthetic fuels often have viscosities that might be close, or even higher, to GTL fuels.  

Do Such Fluids Contain Solid Particles? 

Alternative fuels generally possess a noteworthy advantage over conventional fuels regarding solid particle content. HVO is processed using hydrogen to remove impurities, which helps eliminate virtually all solid particles. GTL fuel also exhibits negligible solid particle content, given its synthesis and refinement processes are designed to yield clean-burning fuels. On the other hand, solid particle content in Synthetic Fuels, which refers to a broader category, is usually minimized through rigorous purification and refinement stages during production processes.  

Despite this overall trend, the presence of solid particles is contingent upon the specific production process employed and the purity of the raw materials used. Hence, solid particles could be present in lower-quality batches or those created using less thorough methods. 

What Pump Types are Best-suited for Such Fuels? 

In this section, let's discuss what pump types are suitable for different alternative fuels. 

Best Pump for HVO Fuels 

HVO, with properties similar to petroleum diesel, can typically be handled in a similar manner. Positive displacement pump designs such as rotary vane pumps or screw are often the best choice due to their inherent high tolerance to variations in viscosity, which can occur in HVO depending on its feedstock.  

Such designs can handle high pressures of 15 bar and above without loss of flow facilitating the delivery HVO efficiently should pressure losses or viscosity change.  

Furthermore, these types of pumps are less prone to wear with Vane pumps having self-compensating vanes to provide consistent delivery of fluids and which ensure continuous contact with the pump casing. Screw pumps contain heavy duty internal screws machined from solid metal, designed to provide many years of robust service, maintaining consistent performance over time. 

Best Pump for GTL Fuels 

The physical properties of GTL make it a prime candidate for centrifugal pumps, specifically of multistage design. It is because of their ability to handle high-pressure and high-flow rate operations. GTL production involves air separation, steam methane reforming, and Fischer-Tropsch synthesis, which involve varying pressure and flow rates. Centrifugal pumps, exclusively those with magnetic drive technology, offer a non-contacting, sealless solution that reduces the chances of leaks. It becomes a vital characteristic when dealing with volatile substances like GTL. 

Best Pump for Synthetic Fuels 

Synthetic fuels present unique challenges due to the variance in their physical and chemical properties based on the process used for their production. Positive displacement pumps, particularly of screw, vane or gear design, are suited to handle such variances.  

They offer superior handling of viscous fluids, a property often found in synthetic fuels. Additionally, such pumps provide a constant and even flow irrespective of changes in pressure, a major advantage in the fluctuating conditions of synthetic fuel transport. Moreover, they are known for their durability and low maintenance requirements, which makes them a cost-effective solution for long-term operation. 

Will Pumps Need to be ATEX for Alternative Fuels? 

Pumps used in the transport and handling of alternative fuels will generally need to meet ATEX (Atmosphères Explosibles) regulations / or UKCA EX. ATEX regulations, designed by the European Union, ensure the safety of equipment and protective systems utilized in potentially explosive environments. Using alternative fuels such as HVO, GTL, and Synthetic Fuels fall under this category due to the possible presence of flammable gas, mist, vapor, or combustible dust in particular when transferred at high pressures.  

Therefore, pumps designed for these applications should be ATEX-certified to ensure they are intrinsically safe and designed to prevent ignition sources like sparks, high temperatures, static discharge and also contain any explosion should one occur. Equipment under ATEX regulations is divided into categories depending on the level of safety they provide and the environment wherein they will be used. As such, select the right pump category that ensures operational efficiency and compliance with safety standards. 

ATEX directives divide equipment into two groups: 

• Group 1: Equipment located underground in places such as mines and surface installations, likely to be endangered by firedamp or combustible dust. 

• Group 2: Equipment in other places likely to be endangered by explosive atmospheres. 

Each group is further categorized to reflect the equipment's level of protection. 

For Group 1: 

Category M1: Equipment designed to remain functional in environments with an atmosphere endangered by methane, dust, or combustible gases. Equipment is designed to operate when an explosive atmosphere is present all or most of the time. 

• Category M2: Equipment for use in environments endangered by methane, dust, or combustible gases which is not to operate in an explosive atmosphere. 

• For Group 2: 

• Category 1 (Zone 0/20): Equipment designed to guarantee a very high level of protection in areas where an explosive atmosphere is present all the time or for long periods. 

• Category 2 (Zone 1/21): Equipment designed to ensure a high level of protection, intended for use in regions where an explosive atmosphere is likely to occur in normal operation. 

• Category 3 (Zone 2/22): Equipment designed to provide a normal level of protection, intended for use in areas where an explosive environment is not likely during normal operation and, should it occur, will do so infrequently and for short periods only. 

The Zone 0, 1, and 2 categorization applies to gases/vapors. On the other hand, Zone 20, 21, and 22 apply to dust environments. Note that these categories help ensure equipment is appropriate for the specific level of risk present envisioned within a normal operating environment. 

Advantages and Disadvantages of HVO Fuels 

HVO fuels boast a range of advantages. They are fully biodegradable, renewable, and sustainable, ensuring an eco-friendly alternative to traditional fuels. The high cetane number provides optimal performance all year round, and the hydrotreatment production process eliminates impurities ensuring less fuel maintenance and safer handling.  

Their widespread approval by many Original Equipment Manufacturers (OEMs) testifies to their quality. An HFRR score of around 350 microns shows superior lubricity and outperforms EN590 diesel. As a drop-in diesel alternative with zero FAME, fossil, and sulfur content, HVO fuels diminish particulate production. They equally cut greenhouse gas emissions by up to 90% and enhance a business's Corporate Social Responsibility (CSR). 

Despite HVO fuels' versatility in utilizing a wider spectrum of raw materials for production, the supply of these resources is finite. Production from palm oil or its waste may inadvertently prompt deforestation and elevated carbon emissions. Even though HVO fuels have lower carbon emissions, their production still results in significant NOx and particulate emissions. Furthermore, HVO is typically pricier than diesel in most markets, which makes it less economically attractive unless redress is taken through taxation of alternatives. 

Advantages and Disadvantages of GTL Fuels 

GTL fuels offer numerous advantages over conventional diesel. They exhibit superior combustion properties, including higher cetane numbers (a measurement of the quality & performance of diesel fuel)  and calorific values, lower sulfur and aromatic levels, and minimal olefins. It results in efficient combustion at lower temperatures and reduced emissions. Their lower density further enhances cold temperature performance.  

They are storable for extended periods without risk of contamination, like traditional biodiesel. This is because they do not hold dissolved or emulsified water, curbing microbial contamination and rust spread. The low water content of GTL also makes it an optimal choice for cold starts, reducing engine heating, minimizing start-up emissions, and increasing starting reliability. What's more, they contribute to smoother, quieter engine operations due to their consistency. Notably, GTL is non-toxic and biodegradable, which reduces fuel spills' environmental and health risks. 

GTL fuels also exhibit some disadvantages, including a lower energy efficiency resulting from diminished energy density compared to traditional fuels. This fuel type also produces a somewhat increased CO2 emission from extraction to utilization compared to standard diesel. Its use can shrink rubber O rings in older engines due to chemical incompatibility, where as elastomer use with traditional fuels causes seals to swell increasing the seal effectiveness. 

Advantages and Disadvantages of Synthetic Fuels 

Synthetic fuels offer benefits, including efficiency, sustainability, strategic value, and innovation potential. Their physicochemical properties align closely with traditional fuels, enabling use in existing vehicles and infrastructure. They leverage alternative and renewable raw materials for production while contributing to environmental sustainability. They help gradually decarbonize transport and aviation sectors. The technological advancement and production of these e-fuels position the refining industry at the cutting edge of low-emission technologies, with potential applications for CO2 capture, utilization, storage, and renewable hydrogen production. 

On the other hand, synthetic fuels have several drawbacks. They are less energy efficient than batteries, requiring four times more electricity than electric vehicles to power combustion engine cars. The infrastructure for synthetic fuels is underdeveloped and makes their production complex, costly, and energy intensive.  

While synthetic fuels release fewer particulates, they emit greenhouse gases like carbon dioxide, sulfur oxide, and nitrogen. Although some manufacturers capture atmospheric carbon to offset emissions, synthetic fuels offer lackluster reductions in CO2 compared to battery-powered EVs, which have the potential to eliminate emissions. As a result, synthetic fuels are often considered inferior regarding their environmental impact. 

How Does Their Price Compare to Diesel / Petrol? 

Alternative fuels often require a more complicated and expensive manufacturing process than petrol and diesel contributing to their higher cost. They are also subject to economies of scale and as the industry is still in its infancy their production infrastructure is not as widespread and mature as that of fossil fuels. This leads to less efficient production and distribution, thus, higher costs. Regulatory policies like carbon taxes and tariffs can also increase fuel costs. 

However certain factors can make alternative fuels cheaper than petrol and diesel. Technological advancements can improve production processes and better energy yield, which reduces production costs. Economies of scale will develop as the industry matures, reducing per-unit costs. Increased demand can also stimulate competition, which can lead to cost reductions.  

Finally, policy incentives like subsidies, tax breaks, and the establishment of a carbon pricing mechanism can make alternative fuels more economically attractive. In addition, as the external costs of carbon emissions become increasingly recognized, the true cost of fossil fuels could be seen as much higher than their market price making alternative fuels more cost-competitive. 

Conclusion 

In conclusion, alternative fuels such as HVO, GTL, and synthetic fuels are essential in our energy transition journey and offer a lower-carbon and potentially more sustainable substitute to conventional fuels. They, however, come with their unique handling and storing requirements, which necessitate an understanding of their specific characteristics like viscosity and particle content.  

While the initial costs and supply chain complexities associated with alternative fuels can make them less economically attractive than traditional fuels, technological advancements, economies of scale, and supportive policy measures will likely make them more competitive.  

For more information on Alternative Fuel Handling HVO GTL and Synthetic Fuels talk to North Ridge Pumps Ltd