Biofuel oil suspension and method for producing same

Abstract

The present invention relates to a biofuel oil suspension that uses biocarbon in its composition. In this scenario, the present invention provides a biofuel oil suspension that contains 5-50% by weight of finely divided biocarbon and 50-95% by weight of oil. The biofuel oil suspension of the present invention is better suited to compressed internal combustion engines (diesel type) currently on the market without major modifications thereto. Furthermore, the biofuel oil suspension of the present invention is highly sustainable and has an energy volume density and viscosity compared to liquid fossil fuels currently on the market.

Description

[Technical Field]

[0001] The present invention relates to fuels, and more particularly to biofuel oil suspensions using solid biocarbon in their composition. [Background technology]

[0002] Internal combustion engines are widely used in industry across sectors such as machine operation, cogeneration, and transportation, across a wide range of production capacities. Internal combustion engines are applied to various modes of transportation in large, medium, and small machines, as well as in the naval, rail, and road sectors. The compression-fired internal combustion engine, commonly referred to as the diesel engine in honor of its inventor, Rudolf Diesel, is extremely relevant.

[0003] Liquid fossil fuels from petroleum distillation are usually used in compressed internal combustion engines. Generally, for large engines, higher viscosity fuels called heavy fuel oil C (HFO-Heavy Fuel Oil C or HFOLS - Low Sulfur Heavy Fuel Oil C), commonly called bunker oil, are used, while for medium and small engines where liquid fossil fuels are used, lower viscosity fuels called diesel oil and gas oil are used.

[0004] Although the above fossil fuels are currently widely used, the world is rapidly moving towards changing its energy matrix, which would imply a course of action for bold efforts towards a zero-carbon emission economy. To achieve this objective of reducing greenhouse gases (GHG) in the transport sector, countries need to adopt a series of measures simultaneously. Biofuels are one of the main players in reducing carbon emissions in the transport sector in several countries.

[0005] As an example, the European Union (EU) recently launched a bold plan known as the "Fit for 55" package to reduce GGE emissions by at least 55% by 2030, which will help member countries achieve the goal of a carbon-neutral EU by 2050 under the Paris Agreement. The plan includes the transport sector, including aviation and shipping, which currently contributes to nearly 40% of total emissions. These trendy efforts to achieve the envisioned goal will be the basis for the European continent to achieve rapid reductions in CO2 emissions.

[0006] Furthermore, it is proposed that by 2035, the use of conventional diesel, petrol, gas or even hybrid technology will be banned in new vehicles, creating room for electric or biodiesel vehicles.

[0007] In this scenario, which is gradually spreading all over the world, biodiesel plays a vital role in providing a complete energy alternative to fossil fuels, as it generally contains raw materials of plant origin in its composition, such as soybean oil, cotton, castor bean, sunflower, babassu, peanut, palm oil, etc.

[0008] In addition to the traditional biodiesel compositions mentioned above, recent research shows the possibility of using coal, especially of mineral origin, in finely divided form (particle size less than 50 μm), which is mixed with a liquid such as water to form an aqueous suspension.

[0009] However, the use of pulverized mineral coal for the production of aqueous suspensions still faces several technical barriers for its practical application, since its physicochemical properties (calorific value, viscosity, and inorganic content) differ from those of the fuels used today and require adaptation to the engines currently on the market.

[0010] Furthermore, solid coal has hydrophobic chemical properties that make it difficult to stabilize when mixed with water. Another relevant point is that experimental results show that the heating value, and hence the energy density, of aqueous coal suspensions is significantly lower than that of fuels currently on the market.

[0011] Finally, the presence of inorganic matter in the composition of the finely divided carbons used in state-of-the-art biofuels generally results in problems of spalling and wear due to abrasion of internal engine parts.

[0012] In the context of seeking sustainability in production processes, biomass pyrolysis technology has been recognized by the technical and scientific communities as a powerful tool for converting biomass into new products, such as charcoal, synthetic gas (syngas), and liquids such as tar and wood pyrolysis extracts. In order to accurately characterize the biomass pyrolysis process, which is carried out strictly under the aspects of operational safety and environmental respect, charcoal has begun to be referred to by other names in the literature, such as biochar or biocarbon. This aforementioned term is adopted in the present invention to refer to the solid products obtained from biomass pyrolysis.

[0013] The proposed invention solves the above prior art problems succinctly and efficiently. Summary of the Invention

[0014] A first object of the present invention is to provide a biocarbon-based biofuel oil suspension that is better suited to compression internal combustion engines currently on the market without major modifications thereto.

[0015] The present invention has a second objective of providing a highly sustainable biocarbon-based oil-based biofuel suspension that has a heating value, energy density, and viscosity compared to fuels currently available on the market.

[0016] To achieve the above object, the present invention provides a biofuel oil suspension containing 5 to 50 mass % of finely divided biocarbon and 50 to 95 mass % of a suspension base liquid.

[0017] The present invention also provides a method for producing the aforementioned biofuel oil suspension, comprising the steps of (i) micronizing biocarbon to a maximum diameter of 50 μm, and (ii) mixing 5-50% by mass of the micronized biocarbon with 50-95% by mass of the suspension base liquid.

[0018] The detailed description set forth below refers to the accompanying drawings and their respective reference numerals. [Brief explanation of the drawings]

[0019] [Figure 1] FIG. 1 is a diagram illustrating a schematic diagram of interactions between various molecules around biocarbon particles in a biofuel oil suspension of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0020] It should be noted in advance that the following description begins with preferred embodiments of the present invention, but as will be apparent to those skilled in the art, the present invention is not limited to these specific embodiments.

[0021] Thus, the present invention provides an oil-based biofuel suspension comprising 5-50% by weight of finely divided biocarbon and 50-95% by weight of the liquid base of the suspension. In this context, finely divided biocarbon is any charcoal of plant origin, produced according to sustainable standards, with a maximum diameter of 50 μm. Preferably, the biocarbon has a low inorganic content (less than 1%).

[0022] Preferably, the liquid base of said suspension is at least one of (i) bunker oil (also known as HFO-C heavy oil), (ii) marine diesel oil (MDO - marine diesel oil or MGO - marine gas oil), (iii) hydrotreated vegetable oil (HVO - hydrotreated vegetable oil), (iv) hydrotreated pyrolysis oil (HPO - hydrotreated pyrolysis oil), and (v) vegetable tar (PO - oil of pyrolysis or pyrolysis oil).

[0023] More preferably, the liquid base of the suspension used in the present invention may be a mixture of at least two of the aforementioned oils in suitable proportions to produce a biofuel with viscosity and energy density comparable to fuel oils found on the market.

[0024] In a first embodiment of the present invention, the following composition is provided: 5-50% by mass of finely divided biocarbon; 50 to 95% by mass of bunker oil; and Marine diesel oil or marine gas oil 0-30% is used.

[0025] In this first embodiment, biocarbon is mixed with bunker oil. Large-scale combustion engines are already prepared to operate with a viscosity typical of bunker oil. Naturally, when solid biocarbon particles are introduced into the suspension, its viscosity tends to increase. Another oil base, diesel oil, or gas oil is then introduced to adjust the viscosity of the suspension and return it to a value close to the inherent viscosity of the bunker. This suspension is characterized by the partial replacement of fossil fuel (bunker) with green fuel (biocarbon). It is a suspension that is highly optimized in terms of technical (combustion) and logistical aspects, since the introduction of biocarbon can be carried out in various proportions and can be implemented in stages.

[0026] In a second embodiment of the present invention, a 100% sustainable composition of: 5-50% by mass of finely divided biocarbon; 50 to 95% by weight of hydrotreated vegetable oil; and Plant tar 0-50% is used.

[0027] In this second embodiment, the biocarbon is mixed with a completely green oil base, which may be HVO (hydrotreated vegetable oil) or vegetable tar (PO pyrolysis oil) or a mixture of these components. This suspension is characterized by a lower viscosity compared to bunker, and in this case we have a sustainable product, i.e. a suspension made up entirely of renewable resources.

[0028] In a third embodiment of the present invention, the following composition, also 100% sustainable: 5 to 50% by mass of finely divided biocarbon; and Hydrotreated pyrolysis oil 50-95% by mass is used.

[0029] In this third embodiment, the suspension is composed of biocarbon and oil-based HPO (hydrotreated pyrolysis oil) and, like the second embodiment, is completely sustainable.

[0030] The three aforementioned embodiments have one feature in common: the use of pulverized biocarbon in the composition. Aiming for a suspension that results in the lowest level of wear due to wear on diesel engines, it is preferred to produce the biocarbon from biomass with a low ash content, for example, preferably bark-free eucalyptus, which has a higher inorganic content compared to the wood core itself.

[0031] The present invention also provides a method for producing the above biofuel oil suspension, comprising the steps of (i) micronizing biocarbon to a maximum diameter of 50 μm, and (ii) mixing 5-50% by mass of the micronized biocarbon with 50-95% by mass of the liquid base of the suspension.

[0032] The present invention refers to an oil-based biofuel suspension whose composition contains a biocarbon fraction from the carbonization of biomass in finely divided form (particles smaller than 50 μm). The presence of biocarbon reduces the amount of greenhouse gases and SO x It offers advantages in ecological terms, such as reduced emissions, in market terms by providing cost savings through the use of cheaper fuel raw materials, and in technological terms.

[0033] The main technical advantage arises from the catalytic effects resulting from the presence of solid biocarbon particles in the reaction atmosphere inside the combustion chamber of the engine. Figure 1 represents a description of these catalytic phenomena, referring to the molecular interactions that occur in this reaction medium.

[0034] First, the internal and external surface areas of biocarbon particles, related to porosity, favor the physical adsorption process of oxygen molecules and other liquid fuels and promote their chemical interaction, which characterizes the catalytic effect of the combustion process. More specifically, biocarbon is a product containing a high carbon concentration, typically greater than 80%, depending on the raw materials and operating conditions under which it is produced. Therefore, biocarbon is a friable and porous product, and these pores can be closed or open. The degree of pulverization determines the external specific surface area of ​​the particles, while the porosity determines the internal specific surface area. Both the external and internal specific surface areas contribute to the phenomenon of heterogeneous catalysis during the combustion process. This effect is illustrated in Figure 1, where HC liquid fuel molecules interact more significantly and more frequently with O2 oxygen molecules, specifically on the internal and external surfaces of BC biocarbon particles. These interactions are highlighted by blue circles in Figure 1.

[0035] Furthermore, the catalytic effect of potassium salt injection on the combustion of solid, liquid, and gaseous fuels is known. From relevant literature, it is also known that during the biomass carbonization process, the migration of inorganic elements present in the precursor biomass occurs, forming pockets of SiO2 and KCl crystals on the surface of the biocarbon particles. Biomass and its respective biocarbons contain micronutrients, such as potassium salts, in their composition. Thus, heterogeneous suspensions containing biocarbons are a unique way to achieve this catalytic effect of potassium in the combustion process. Potassium reduces the activation energy and catalyzes the reaction between oxygen and the carbon surface of the biocarbon itself. This effect is illustrated in Figure 1 and highlighted by the orange circles.

[0036] Optionally, the present invention also provides for the introduction of additives, such as surfactants, into the biocarbon-based biofuel oil suspension to improve the stability of the solution and its handling, transport, and storage properties. The additives may be used in small proportions, typically less than 5%.

[0037] In addition to the innovative effects listed above, the following advantages are observed in the biofuel of the present invention: 1) The friability of biocarbon allows for crushing to obtain particles with typical dimensions below 50 μm at relatively competitive operating costs; 2) Preferably, the biocarbon is micronized to achieve a bimodal particle size distribution that is favorable for the preparation of the oil suspension of the present invention; 3) Biocarbon has a low ash and sulfur content when compared to other carbonaceous materials, such as mineral coal; 4) The catalytic process associated with biocarbon improves the combustion characteristics of the suspension and thus enhances the performance of the diesel engine; 5) The burn time of porous biocarbon particulates, typically the stroke time of many diesel cycle engines of interest for the industrial applications of the present invention, such as low-speed engines used in marine transport, is short, resulting in full solid fuel combustion efficiency and low levels of particulate emissions; 6) Catalytic optimization of the combustion process of the oily phase of the suspension and the biocarbon particles themselves allows the engine to be operated at a lower compression level, thus resulting in a better thermal efficiency of the engine; 7) Pollutants resulting from catalytic combustion processes associated with biocarbon particles, such as particles and NO x Good performance regarding atmospheric emissions; 8) The biofuel oil suspension of the present invention is partially or completely renewable, thus helping to reduce greenhouse gas emissions in the form of CO2 into the atmosphere.

[0038] The biofuel of the present invention has a viscosity, calorific value, and energy density that can be adjusted for the application. In this way, the biofuel of the present invention can be adjusted to replace any type of diesel oil currently on the market. For example, the present invention can be very effectively used to replace bunker oil for applications in low-speed engines such as marine engines. However, its application is not limited to this specific application and can also be used in engines in rail, road, and air transportation, mechanical mobility, and cogeneration.

[0039] Therefore, as explained above, the present invention provides a biofuel oil suspension that is better suited to diesel engines currently on the market without major modifications to the engines. Furthermore, the biofuel oil suspension of the present invention is highly sustainable and has a calorific value, energy density, and viscosity compared to fuels currently on the market.

[0040] Many variations are permitted that affect the scope of protection of this indication, and it is thus emphasized that the present invention is not limited to the specific configurations / embodiments described above.

Claims

1. 5 to 50% by weight of finely divided biocarbon; and Liquid suspension base 50-95% by weight 13. A biofuel oil suspension comprising:

2. The liquid base of the suspension is Bunker oil; Marine diesel or marine gas oil; Hydrotreated vegetable oils; Hydrotreated pyrolysis oil; and Plant Tar 2. The biofuel oil suspension according to claim 1, characterized in that the oil suspension is at least one of the following:

3. The liquid base of the suspension is Bunker oil; Marine diesel oil; Hydrotreated vegetable oils; Hydrotreated pyrolysis oil; and Plant Tar 3. The biofuel oil suspension according to claim 2, characterized in that it is a suspension of at least two of the following:

4. 5 to 50% by mass of finely powdered biocarbon; 50 to 95% by mass of bunker oil; and Marine diesel oil 0-30% 4. Biofuel oil suspension according to claim 2 or 3, characterized in that it comprises:

5. 5 to 50% by mass of finely powdered biocarbon; 50 to 95% by weight of hydrotreated vegetable oil; and Vegetable tar 0-50% 4. Biofuel oil suspension according to claim 2 or 3, characterized in that it comprises:

6. 5-50% by weight of finely divided charcoal; and Hydrotreated pyrolysis oil 50-95% by mass 4. Biofuel oil suspension according to claim 2 or 3, characterized in that it comprises:

7. 1. A method for producing a biofuel oil suspension, comprising: Micronizing the biocarbon to a maximum diameter of 50 μm; Mixing 5-50% by weight of the micronized bio-carbon into 50-95% by weight of the liquid suspension base. The method of claim 1, further comprising:

8. 8. The method of claim 7, wherein the biocarbon has a bimodal particle size distribution.

9. The liquid base of the suspension is Bunker oil; Marine diesel oil; Hydrotreated vegetable oils; Hydrotreated pyrolysis oil; and Plant Tar The method according to claim 7 or 8, characterized in that the method is at least one of the following:

10. The liquid base of the suspension is Bunker oil; Marine diesel oil; Hydrotreated vegetable oils; Hydrotreated pyrolysis oil; and Plant Tar The method according to claim 9, characterized in that the at least two of the following are present:

11. 11. The method according to any one of claims 7 to 10, characterized in that it additionally comprises the step of adding at least one surface-active additive to the biofuel oil suspension.

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