Oily biofuel suspension and method for manufacturing same

Abstract

The present invention relates to oily biofuel suspensions with biocarbon in their composition. The present invention provides an oily biofuel suspension comprising 50% by mass micronised biocarbon and 50-95% by mass oil. The oily biofuel suspension according to the present invention is better suited to existing, commercially available internal combustion engines with compression (diesel type), dispensing with greater retrofitting outlays of same. Moreover, the oily biofuel composition according to the present invention is highly sustainable and has an energy volumetric density and viscosity comparable to those of the existing, commercially available liquid fossil fuels.

Description

BIOFUEL OIL SUSPENSION AND ITS MANUFACTURING PROCESS FIELD OF INVENTION

[0001] The present invention relates to fuels. More specifically, the present invention relates to biofuel oil suspensions that employ solid biocarbon in their composition. BACKGROUND OF THE INVENTION

[0002] Internal combustion engines are widely used in industrial applications, spanning segments such as machine movement, cogeneration, and transportation, covering a wide range of capacities. They are used in various modes of transportation, in large, medium, and small machines, and in the naval, railway, and road sectors. Of particular importance are compression-fired internal combustion engines, commonly referred to as diesel engines, after their inventor, Rudolph Diesel.

[0003] Compression-driven internal combustion engines typically use liquid fossil fuels derived from petroleum distillation. Large engines generally use higher-viscosity fuels called heavy fuel oils (HFO or HFOLS), commonly called bunker oil, while medium- and small-sized engines use lower-viscosity fuels called diesel oil and gas oil.

[0004] Although the aforementioned fossil fuels are currently widely used, the world is rapidly moving toward changing its energy mix, which will require a bold agenda of commitments toward a zero-carbon economy. To achieve this goal of reducing greenhouse gases (GHGs) in the transportation sector, countries will have to simultaneously adopt a set of measures. Biofuels are among the main drivers of greenhouse gas reduction. carbon emissions in the transport sector in several countries.

[0005] For example, the European Union (EU) recently launched a bold plan to reduce greenhouse gas emissions by at least 55% by 2030, known as the "Fit for 55" Package. This will help member countries achieve the goal of a carbon-neutral EU by 2050, as established by the Paris Agreement. The plan includes the transportation sectors, including aviation and maritime—currently responsible for nearly 40% of all emissions. The commitment of these modes to the targets will be crucial for the European continent to achieve a rapid reduction in CO2 emissions.

[0006] Additionally, it is proposed to ban the use of conventional diesel, gasoline, gas, or even hybrid technology in new vehicles by 2035, creating space for electric or biodiesel-powered vehicles.

[0007] In this scenario, which is gradually spreading throughout the world, biodiesel plays a very important role in providing an energy alternative to entirely fossil fuels, since its composition generally contains raw materials of vegetable origin, such as soybean, cotton, castor, sunflower, babassu, peanut, palm oil, etc.

[0008] In addition to the conventional biodiesel composition previously described, recent studies show the possibility of using coal, especially of mineral origin, in micronized form (granulometry less than 50 pm) mixed with a liquid, such as water, forming an aqueous suspension.

[0009] However, the use of micronized mineral coal for the manufacture of aqueous suspensions still faces several technical barriers to its practical application, since its physical-chemical properties (calorific value, viscosity and inorganic content) differ from those of fuels. used today, which requires adaptations to the engines currently on the market.

[0010] Furthermore, solid coal has a hydrophobic chemical nature, which hinders its stability when mixed with water. Another relevant point is that experimental results show that the calorific value of aqueous coal suspension, and therefore its energy density, is considerably lower than that of commercially available fuels.

[0011] Finally, the presence of inorganic materials in the composition of micronized coals used in state-of-the-art biofuels commonly generates problems with fouling and abrasive wear on the internal components of engines.

[0012] In the pursuit of sustainability in production processes, biomass pyrolysis technology has been recognized by the technical and scientific community as a powerful tool for transforming biomass into new products such as charcoal, synthesis gas (syngas), and liquids such as tar and pyroligneous extract. Precisely to characterize a biomass pyrolysis process executed with rigor, taking into account operational safety and environmental considerations, charcoal has been given other names in the literature, such as biochar or biocarbon. This latter term will be adopted in this invention to designate the solid product obtained from biomass pyrolysis.

[0013] The invention proposed here solves the problems of the prior art described above in a simple and efficient manner. SUMMARY OF THE INVENTION

[0014] The present invention has as a first objective to provide a biocarbon-based biofuel oil suspension better adapted to the compression internal combustion engines currently on the market, dispensing with major adaptations to them.

[0015] The present invention has as a second objective to provide a highly sustainable biocarbon-based biofuel oil suspension with calorific value, energy density and viscosity comparable to fuels currently on the market.

[0016] In order to achieve the objectives described above, the present invention provides a biofuel oil suspension, comprising 5 to 50% by mass of micronized biocarbon and 50 to 95% by mass of suspension base liquid.

[0017] The invention also provides a process for manufacturing the aforementioned biofuel oil suspension comprising the steps of (i) micronizing biocarbon to a maximum diameter of 50 pm and (ii) mixing 5 to 50% by mass of micronized biocarbon with 50 to 95% by mass of suspension base liquid. BRIEF DESCRIPTION OF THE FIGURES

[0018] The detailed description presented below refers to the attached figure and their respective reference numbers.

[0019] Figure 1 illustrates a schematic diagram of the interaction between the various molecules around a biocarbon particle in the biofuel oil suspension of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0020] As a preliminary point, it should be noted that the following description will be based on preferred embodiments of the invention. As will be evident to anyone skilled in the art, however, the invention is not limited to these particular embodiments.

[0021] The present invention therefore provides a biofuel oil suspension comprising 5 to 50% by mass of micronized biocarbon and 50 to 95% by mass of the liquid base of the suspension. For the purposes of this description, micronized biocarbon means any charcoal of vegetable origin, produced according to sustainable standards, with a diameter maximum of 50 ends. Preferably, this biocarbon has a low inorganic content (less than 1%).

[0022] Preferably, the liquid base of the aforementioned suspension is at least one of (i) bunker oil (also known as HFO - Heavy Fuel Oil), (ii) marine diesel oil (MDO - Marine Diesel or MGO - Marine Gasoil), (iii) hydrotreated vegetable oil (HVO - Hydrotreated Vegetable), (iv) hydrotreated pyrolysis oil (HPO - Hydrotreated Pyrolysis), and (v) vegetable tar (also known as PO - Pyrolysis Oil or Pyrolysis).

[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 generate a biofuel with viscosity and energy density equivalent to fuel oils found on the market.

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

[0025] In this first step, biocarbon is mixed with bunker oil. Large combustion engine engineering is already designed to operate with a typical bunker oil viscosity. Naturally, as solid biocarbon particles are introduced into the suspension, its viscosity tends to increase. Another oil base, diesel oil, is then introduced to adjust the suspension viscosity and return it to values ​​close to the original bunker viscosity. This suspension is characterized by the partial replacement of fossil fuel (bunker) with green fuel (biocarbon). It is a suspension that is highly optimized from a technical (combustion) and logistical perspective, since the introduction of biocarbon can be carried out in different proportions and implemented gradually.

[0026] In a second embodiment of the present invention, 100% sustainable, the following composition is employed: 5 to 50% by mass of micronized biocarbon; 50 to 95% by mass of hydrotreated vegetable oil; and 0 to 50% of vegetable tar.

[0027] In this second embodiment, the biocarbon is mixed with a completely green oil base, which can be HVO (Hydrotreated Vegetable Oil) or vegetable tar (PO Pyrolysis Oil), or a mixture of these components. This suspension has a lower viscosity compared to bunker oil, and in this case, the suspension consists solely of sustainable products, that is, of renewable origin.

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

[0029] In this third embodiment, the suspension is composed of biocarbon and the oil base HPO (Hydrotreated Pyrolysis Oil) and, like the second embodiment, is totally sustainable.

[0030] The three aforementioned embodiments share a common characteristic: the use of micronized biocarbon in their composition. To achieve suspensions that result in the lowest level of abrasive wear in diesel engines, it is preferable to produce biocarbon from low-ash biomass, such as eucalyptus, preferably without the bark, which has a higher inorganic content compared to the heartwood itself.

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

[0032] The present invention relates to a biofuel oil suspension whose composition includes a portion of biocarbon from the carbonization of biomass in micronized form (particles smaller than 50 pm). The presence of biocarbon provides ecological advantages, such as reduced greenhouse gas and SO2 emissions. X , in marketing aspects, by bringing cost reduction through the use of cheaper fuel raw materials and in technical aspects.

[0033] The main technical advantages derive from the catalytic effects of the presence of solid biocarbon particles in the reacting atmosphere within the engine's combustion chamber. Figure 1 illustrates these catalytic phenomena, highlighting the molecular interactions that occur in this reacting environment.

[0034] First, the internal surface area associated with porosity, as well as the external surface area of ​​biocarbon particles, favors the physical adsorption of oxygen molecules and other liquid fuels, promoting chemical interaction between them, which characterizes a catalytic effect in the combustion process. More specifically, biocarbon is a product with a high carbon concentration, typically greater than 80%, depending on the raw material and operational production conditions. It is, therefore, a friable and porous product, with these pores being either closed or open. Associated with the degree of micronization, the specific external surface area of ​​the particles is generated, and associated with porosity, the specific internal surface area of ​​the particles is generated. Both the external and internal specific surface area contribute to the phenomenon of heterogeneous catalysis during the combustion process.This effect is illustrated in figure 1, where the. Liquid fuel molecules (HC) interact more significantly and frequently with oxygen molecules (O2) precisely on the inner and outer surfaces of biocarbon particles (BC). These interactions are highlighted in Figure 1 with a blue circle.

[0035] Additionally, the catalytic effect of injecting potassium salts into the combustion of solid, liquid, and gaseous fuels is well known. It is also known from the relevant literature that, during the biomass carbonization process, inorganic elements present in the precursor biomass migrate, forming pockets of SiO2 and KCl crystals on the surface of the biocarbon particle. Biomass and its biocarbon composition contain micronutrients, including potassium salts. Thus, the heterogeneous suspension containing biocarbon is an intrinsic way to achieve this catalytic action of potassium in the combustion process. This effect, where potassium reduces the activation energy and catalyzes the reaction of oxygen with the carbonaceous surface of the biocarbon, is illustrated in Figure 1 and highlighted with an orange circle.

[0036] Optionally, the present invention further provides for the introduction of additives into the biocarbon-based biofuel oil suspension, such as surface-active agents, to improve the solution's stabilization and its handling, transportation, 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 grinding to obtain particles with typical dimensions of less than 50 pm at relatively competitive operating costs; 2) Preferably, the biocarbon is micronized to achieve a bimodal particle size distribution, which favors preparation of the oily suspension of this invention; 3) Biocarbon has a low ash and sulfur content when compared to other carbonaceous materials, such as coal; 4) Catalytic processes associated with biocarbon improve the combustion properties of the suspension and, therefore, increase the performance of the diesel engine; 5) The burn times of the porous biocarbon microparticles are short, typically at the same stroke times as many diesel-cycle engines of interest in terms of industrial applications of the present invention, such as, for example, low-speed engines used in maritime transport. This provides complete combustion efficiency of the solid fuel and low particulate emissions; 6) Catalytic optimization of the combustion processes of the suspension's oil phase and the biocarbon particle itself allows the engine to operate at lower compression levels and, therefore, results in greater thermal efficiency of the engine; 7) Better performance in relation to atmospheric emissions of contaminants such as particulates and NO X due to the catalytic combustion process associated with biocarbon particles; 8) Because it is renewable, partially or totally, the biofuel oil suspension of the present invention promotes a reduction in greenhouse gas emissions in the form of CO2 into the atmosphere.

[0038] The biofuel of the present invention has its viscosity, calorific value, and energy density adjustable to its applications. Thus, it can be adapted to replace any type of diesel currently on the market. For example, the present invention can be used very efficiently to replace bunker oil in low-speed engine applications. such as marine engines. However, their application is not limited to this specific application, and can also be used in engines used in rail, road, and air transportation, machine movement, and cogeneration.

[0039] Thus, as explained above, the present invention provides a biofuel oil suspension better adapted to diesel engines currently on the market, eliminating the need for major adaptations. Furthermore, the biofuel oil suspension of the present invention is highly sustainable and has a calorific value, energy density, and viscosity comparable to fuels currently on the market.

[0040] Numerous variations affecting the scope of protection of this application are permitted. This reinforces the fact that the present invention is not limited to the particular configurations / embodiments described above.

Claims

CLAIMS 1. Biofuel oil suspension, characterized by comprising: 5 to 50% by mass of micronized biocarbon; and 50 to 95% by mass of the liquid base of the suspension.

2. Biofuel oil suspension, according to claim 1, characterized in that the liquid base of the suspension is at least one of: bunker oil; marine diesel oil or gas oil; hydrotreated vegetable oil; hydrotreated pyrolysis oil; and vegetable tar.

3. Biofuel oil suspension, according to claim 2, characterized in that the liquid base of the suspension is a suspension of at least two of: bunker oil; marine diesel oil; hydrotreated vegetable oil; hydrotreated pyrolysis oil; and vegetable tar.

4. Biofuel oil suspension, according to claim 2 or 3, characterized by comprising: 5 to 50% by mass of micronized biocarbon; 50 to 95% by mass of bunker oil; and 0 to 30% marine diesel oil.

5. Biofuel oil suspension, according to claim 2 or 3, characterized by comprising: 5 to 50% by mass of micronized biocarbon; 50 to 95% by mass of hydrotreated vegetable oil; and 0 to 50% vegetable tar.

6. Biofuel oil suspension, according to claim 2 or 3, characterized by comprising: 5 to 50% by mass of micronized charcoal; and 50 to 95% by mass of hydrotreated pyrolysis oil; 7. Manufacturing process for a biofuel oil suspension, characterized by comprising the steps of: micronizing biocarbon to a maximum diameter of 50 µm; mixing 5 to 50% by mass of micronized biocarbon with 50 to 95% by mass of the liquid base of the suspension.

8. Process according to claim 7, characterized by the biocarbon having a bimodal particle size distribution.

9. Process according to claim 7 or 8, characterized in that the liquid base of the suspension is at least one of: bunker oil; marine diesel oil; hydrotreated vegetable oil; hydrotreated pyrolysis oil; and vegetable tar.

10. Process according to claim 9, characterized in that the liquid base of the suspension is at least two of: bunker oil; marine diesel oil; hydrotreated vegetable oil; hydrotreated pyrolysis oil; and vegetable tar.

11. Process, according to any one of claims 7 to 10, characterized by further comprising a step of adding at least one surfactant additive to the biofuel oil suspension.