Patent Application
20250179977
The present invention relates to a hydrogen generator device that produces a pre-determined hydrogen/oxygen mixture, with a controlled flow that automatically adjusts according to immediate demand, featuring low energy consumption and high electrode durability, intended to be used as a combustion optimizer and pollutant emission reducer in diesel cycle engines.
Due to its high calorific value and the fact that the result of its combustion generates only water vapor, hydrogen has been the subject of attempts to use it as fuel in internal combustion engines for many decades.
Hydrogen has the potential to be used alone as a fuel, or to partially replace other fuels. The partial or total replacement of hydrocarbons, such as gasoline, diesel, ethanol and methane or petroleum gas by hydrogen, aims to increase the efficiency of the combustion reaction and reduce the products and intermediates of the incomplete reaction, with a positive environmental impact and a reduction in total fuel consumption.
However, due to the significant challenges in materials engineering, it was decided to use in situ hydrogen generator devices installed alongside the engines, which convert an electrolyte solution into hydrogen for immediate use.
The main limitation to the use of these hydrogen-generating devices has been their high energy consumption, which can make it unsustainable, technically and economically, when compared to the energy supply capacity of internal combustion engines. The generation of significant quantities of hydrogen, which can be used as a partial substitute for fuel in internal combustion engines, requires the use of a quantity of energy that, in the long term, cannot be sustained by the alternator/battery combination of commercial engines. When hydrogen-generating devices are installed for partial fuel replacement, therefore, the useful life of the batteries is usually reduced to little more than the autonomy provided by a few fuel tanks.
Another limiting factor for the adoption of hydrogen-generating devices in internal combustion engines is the useful life of the electrodes. Water electrolysis induces corrosive processes in the anode, resulting in rapid wear of the electrodes, which requires frequent maintenance. This implies a loss of time and increased costs.
The mixture of hydrogen with fuels can have two important roles in combustion. The first and most obvious role is to serve as fuel. The second, less obvious and less well-known, is to add a proportion of reducing hydrogen atoms (from the H2 molecule) to the fuel mixture. The hydrogen/fuel mixture in the correct quantities optimizes combustion, making it more complete and allowing the engine to convert a greater proportion of the heat energy into a driving force. The more complete combustion reaction reduces fuel consumption per unit of driving work performed by the engine, with less formation of intermediate and partially oxidized compounds, which reduces pollutant emissions.
In order to fulfill only its second role, of adding a certain amount of reducing hydrogen to the fuel mixture, the amount of hydrogen required is much smaller than that required for its use as fuel. In this context, the adequate amount of hydrogen gas admitted together with the fuel already plays the important role of optimizing the combustion reaction, with direct implications for the efficiency of the reaction and the emission of pollutants.
In gas form, hydrogen (H2) is in its reduced form and not in its oxidized form (as in water, H2O), in a way that this gas participates in the combustion reaction. In hydrocarbons, carbon is in its reduced form (carbons bonded to hydrogen), so it is the carbon that participates in the combustion reaction. Only in its reduced form is the reaction of carbon or hydrogen with oxygen exothermic. In other words, the hydrogen in hydrocarbons does not contribute to the explosion and the formation of heat in internal combustion engines. However, the combustion temperature and the burning rate of hydrogen are higher than those of hydrocarbons, 2 and 9 times higher than that of diesel, respectively, so that, theoretically, the addition of hydrogen in its reduced form has the potential to improve the combustion efficiency of hydrocarbons in internal combustion engines.
Hydrogen is highly flammable in a wide range of mixtures with oxygen. This is because it requires low ignition energy, so that the mere contact with hot parts of the cylinder, with temperatures above 60° C., can generate its ignition. Despite the low ignition temperature, its combustion temperature is high, which promotes a higher compression ratio, which is directly related to the engine's greater energy efficiency. High flammability would be a defect of hydrogen, as it can trigger the combustion of the mixture prematurely, i.e., before the combustion chamber closes. Potentially damaging the operation and durability of the valve system. On the other hand, the higher combustion temperature generates a higher compression ratio, which is one of the advantages of adding hydrogen to the fuel mixture.
Hydrogen has greater diffusivity during combustion when compared to hydrocarbons. Thus, the mixture of hydrogen and hydrocarbons has the potential to homogenize the fuel-air mixture and standardize the concentration distribution of the fuel mixture in the combustion chamber.
The greater emission of soot and pollutant gases in diesel engines is a result of the incomplete combustion of the fuel, which produces intermediates and partially oxidized products. The heterogeneity of the fuel concentration distribution in the combustion chamber creates denser and less dense zones, compromising the homogeneity of consumption of the fuel mixture, which induces incomplete combustion. For this reason, the addition of hydrogen helps to homogenize the fuel mixture, with the potential to make combustion more complete, by increasing the efficiency in converting thermal energy into driving force and reducing the emission of soot and pollutant gases.
In addition to inescapable thermodynamic conditions, such as operation between different temperatures as a derivative of the Carnot cycle, most internal combustion engines have a low-efficiency rate of conversion of thermal energy into driving energy due to incomplete combustion, limiting efficiency to values below 43%. This results in the fact that they emit polluting combustion residues. Both solid residues, such as soot, and gaseous residues, such as NOx, CO, SO2, etc.
The main reason for incomplete combustion is the unevenness of the mixture of fuels with oxygen in the air and the uneven distribution of the fuel mixture throughout the combustion chamber. As a result, combustion occurs in different zones within the combustion chamber, generating different residues in each phase of the process. This happens because the oxidizing oxygen present in the air in the mixture is consumed unevenly. In fact, instead of one single uniform combustion that consumes the entire mixture injected into the combustion chamber, several different combustions occur, with different temperatures, oxygen consumption and efficiencies. This generates an average incomplete combustion and, consequently, the emission of a series of substances resulting from incomplete combustion. Instead of just water and carbon dioxide, which would be the theoretical emissions of complete combustion.
The widespread use of turbo compressors in internal combustion engines, which enrich the fuel mixture with oxygen, has further increased the need to increase the proportion of hydrogen in the combustion reaction, since atmospheric air contains practically no hydrogen and the mixture becomes even richer in oxygen. In this case, the hydrogen gas would have the role of increasing the homogeneity of the mixture, due to the high speed of its flame and its higher combustion temperature. In practice, its combustion will homogenize the fuel mixture and uniformize its distribution in the combustion chamber, in order to make combustion more complete.
Each new generation of engines seeks to make the mechanics of the mixture of hydrocarbon fuel with air more homogeneous and to make its dispersion in the combustion chamber more uniform. In this context, the potential for improving combustion provided by a certain amount of hydrogen in a Euro II diesel engine is greater than in a Euro III engine, for the same engine fuel consumption; and so forth.
Many studies have been conducted to evaluate the use of hydrogen as a partial substitute, or even an additive, for hydrocarbons and alcohols used as fuels, such as diesel, gasoline, ethanol and petroleum gas. All of these studies used concentrations of 3 to 30% hydrogen in the fuel mixture. Apparently, tests with less than 3% concentration were not performed because they assumed that its effect would be insignificant. They also did not use more than 30%, probably because they assumed that such a concentration would be technically and economically unfeasible, due to the high energy demand for hydrogen generation, the high temperature to which the engine would be subjected and the need to store large quantities of the gas.
The vast majority of these studies showed inconclusive or unstable results, technically and economically, casting doubt on the viability of adding hydrogen to fuel hydrocarbons. This is because there is no linearity of results as the hydrogen concentration in the mixture varies. In other words, the results of the studies do not show a clear relationship between engine efficiency and the increase in hydrogen concentration in the mixture. This may happen due to other important variables, such as oxygen concentration, combustion chamber architecture and homogeneity of the injected mixture, which begin to act as limiters of combustion efficiency. Part of this inconsistency in practical results is due to factors such as track topography, air temperature and humidity and engine vibration.
The amount of hydrogen to be injected into the fuel mixture can be measured in milliliters/minute per liter/hour of fuel. This can be a complex task since it is a gas that is produced and injected simultaneously with the intake air. On the other hand, there is a direct correlation between the amount of hydrogen produced and the energy required for its production. Thus, an alternative and more practical way of measuring the amount of hydrogen produced and injected into the intake air would be through the energy consumed by the generating device used. Since the hydrogen production capacity, as well as the energy, of each device is proportional to the engine's fuel consumption, the measurement of the hydrogen injection rate into the mixture can also be defined in energy (W)/fuel consumption (l/h).
The inventors are aware of U.S. Pat. No. 10,253,685 B2 Apr. 9, 2019, which is related to the use of hydrogen for combustion engines.
The inventors are aware of US patent 2017/0254259 A1 Sep. 7, 2017, which relates to the use of hydrogen for combustion engines.
The inventors are aware of the patents and applications U.S. Pat. No. 7,430,991, US 2018/058287, CA 2945891, and US 2005/217991, which relate to the use of hydrogen for combustion engines.
The prior art includes many inventions that differ from the present invention in the following aspects:
Document US2013061822 reports an engine enhancement system and method that uses hydrogen as a combustion catalyst within an internal combustion engine, the hydrogen being preferably obtained and/or replenished from a supply of HHO gas feeding the engine's combustion chambers, and being located in interstitial locations in the walls of the combustion chambers. The document does not specify the composition of the hydrogen/oxygen mixture, limiting itself to the theoretical composition of 2:1 (H2:O2). The document also does not specify the types of electrodes used. The document also does not specify in detail which variables are sensitive to the action of the controller that regulates the potential difference applied to the electrolyzer. The document indicates the option of installing a controller capable of alternating the polarity of the electrodes, and in addition to not being mandatory, the exchange would only occur each time the vehicle is started.
Document U.S. Pat. No. 10,253,685 reports a method for reducing pollutant gases and saving fuel by admitting a hydrogen/oxygen mixture. The document relates to a manual, partially automatic or automatic monitoring and adjustment system for the admission of the gas mixture. The document does not describe the electrolyzer in detail, nor its components. Additionally, this document does not explore in detail the response of the variation in flow and composition of the gas mixture to operational variables.
Document CN 103789785 teaches a water electrolysis device for producing a hydrogen/oxygen mixture for an internal combustion engine, characterized by: an electrolytic cell, a general opening switch and a control detection component. The cell is composed of a graphite cathode and a titanium alloy anode separated by a separating device. The electrolyzer is very well described and makes it clear that it is a device with two independent compartments, a cathode containing the catholyte and an anode containing the anolyte, solutions that should preferably have the same pH, depending on the type of ion-permeable separator used, if any. The use of titanium alloy as the anode increases the stability of the catalyst in aqueous solution, as predicted in Pourbaix diagrams. However, the use of electrodes with different compositions prevents polarity exchange and makes it imperative to use a separator, which can increase the maintenance cost of the device, in addition to imposing additional polarizations due to ohmic drop.
The present invention was developed to solve problems in the prior art in order to make it technically and economically viable:
A hydrogen-generating device/electrolyzer was developed to improve diesel combustion in internal combustion engines that met the following requirements:
The following figures illustrate the invention from various aspects:
As its objective, the present invention has a hydrogen-generating device, combustion optimizer and pollutant emission reducer in diesel cycle engines, capable of producing an adequate and controlled quantity of hydrogen to be injected into the engine and comprises:
This invention relates to a hydrogen-generating device, combustion optimizer and pollutant emission reducer in diesel cycle engines, according to the invention, it generates small quantities of hydrogen to be injected into the engine and comprises:
The device features an alternation of polarity between the electrodes from one to three times per minute, preferably twice per minute.
The hydrogen-generating device is capable of injecting a quantity of up to 10%, preferably up to 9%, and more preferably up to 8% and even more preferably 6% of the hydrogen:oxygen mixture, in the ratio of 65:35, per liter of diesel consumed in a volume/volume ratio.
In mass/mass, the ratio between the hydrogen:oxygen mixture (65%:35%) and the diesel, in this invention, is of the order of 0.005:1 (5 thousandths). The generator maintenance time was strategically engineered to coincide with the average oil change time of a diesel cycle engine.
The electrolyzer based on cast aluminum alloy has heat exchanger fins on the outside.
The electrolyzer has an optimized electrolytic solution and catalytic electrodes inside. The electrolyzer comprises two electrodes in the same electrolytic solution.
The electrolytic solution may be composed of different concentrations of salts, bases and a stable organic additive. The salts promote ionic mobility, the base added to the salt is responsible for optimizing the pH, while the stable organic additive is responsible for promoting coloration. The non-toxic solution has different formulations, optimized for a commercial solution identified as GFNa, where “N” describes the composition and “a” describes the presence or absence of the additive.
According to a preferred embodiment of the invention, the aqueous electrolyte solution comprises from 0.01 to 0.50 mol L−1 of NaHCO3, 0.01 up to 0.50 mol L−1 of KOH and even 0.001 to 0.100 mol L−1 of an organic additive with formula C16H10N2Na2O7S2, or any other with the same role.
According to another preferred embodiment of the invention, the electrolyte solution comprises: 0.05 to 0.15 mol L−1 of NaHCO3, 0.05 up to 0.10 mol L−1 of KOH and an additive with formula C16H10N2Na2O7S2 to give an orange color, or any other type of dye with the same role.
Both the anode and the cathode may be composed of materials chosen from the group comprising: transition metals from group d, noble or non-noble metals, stainless steel, glass, thermosetting polymer and carbon, or their alloys. Preferably, for both, stainless steel or derivatives of different stainless steel alloys are used in formats such as: rods, helicoids or cylinders. Preferably, the rod format is used.
The hydrogen-generating device, combustion optimizer and pollutant emission reducer in diesel cycle engines, according to the invention, can be used in a diesel cycle engine with consumption of up to 20 liters/h, and the same vehicle can use one or more devices according to the invention.
For the production of hydrogen and oxygen, or electrolysis of water, the device according to the invention has an energy consumption of less than 3.0 Watts/liter of diesel, and this consumption depends on the operating conditions of the engine.
The hydrogen-generating device, which optimizes combustion and reduces pollutant emissions in diesel cycle engines, according to the invention, contributes to the environment by injecting into the engine a quantity of up to 10% of the hydrogen:oxygen mixture, in the ratio of 65%:35%, per liter of diesel consumed in a volume/volume ratio. The device has a long useful life due to the periodic alternation of polarity between the electrodes immersed in the electrolyte solution of the electrolyzer, with frequencies that can vary from one to three times per minute. The device has optimized heat exchange due to the presence of external fins in a cast aluminum alloy cell. The assembly produces a flow of a hydrogen/oxygen mixture preferably operating in a 65:35 (H2:O2) ratio of 10 to 50 mL/min, preferably 10 to 30 mL/min, and more preferably operating at an average of 12.5 mL/min in steady state and at 20 mL/min installed in the truck at average rotation on flat ground. Gas production is controlled by an electronic module sensitive to topography and rotation that operates potentiostatically, with direct control of the applied potential, or galvanostatically, with indirect control of potential due to direct control of the output current.
According to a preferred embodiment of the invention, the hydrogen-generating device, which optimizes combustion and reduces pollutant emissions in diesel cycle engines, generates a quantity of up to 9% of hydrogen:oxygen mixture to be injected, per liter of diesel consumed in a volume/volume ratio, and comprises:
This invention sought to solve the two main bottlenecks that have made it technically and economically unfeasible to adopt hydrogen-generating devices to improve combustion and reduce pollutant emissions in diesel cycle engines. These bottlenecks are the short lifespan of the electrodes involved in the electrolysis and the rapid deterioration of the engine's alternator/battery assembly.
According to another embodiment of the invention, the device comprises:
The device of this invention injects hydrogen into the engine in a variable manner, which is controlled by an electronic board that defines the engine's operating condition, according to its rotation and the topography of the track, without the need for connection to the vehicle's telemetry or WiFi network, which provides reliability and low operating costs for the device. The variation in the hydrogen generation rate aims to prolong the operational condition of the electrolyte and the useful life of the electrodes, as well as reduce energy consumption for the system.
Another innovation of this invention is the periodic and controlled change of the polarity of the electrodes. This is also controlled by the electronic module board that controls the device. With the periodic change of polarity, each electrode works for a period as an anode and then for a period as a cathode. This occurs thousands of times during the operating period and can be adjusted for different frequencies. This strategy minimizes the irreversible oxidation of the anode because the surface oxide is reduced when the polarity is reversed, which increases the stability of the electrodes and allows the use of low-cost materials, such as stainless steel-based alloys. This process assists in maintaining the physical-chemical composition of the electrodes and the electrolytic solution, which enables the production of gases with an unchanged composition throughout the operating period.
Another innovation of this invention is the dual operation of the electronic module, which can work both potentiostatically, with direct control of the voltage applied to the electrodes, and galvanostatically, with indirect control of the voltage due to the maintenance of the output current. In galvanostatic mode, the output current is kept constant, and to achieve this, resistors inserted in the electronic module are automatically exchanged, varying the voltage to deliver the same current, making the output gas flow unequivocally constant throughout the entire operating period. The galvanostatic mode also maintains the generator temperature, since, like the gas flow, the temperature is proportional to the current flowing through the system.
This invention is characterized by the injection of an adequate amount of hydrogen into hydrocarbon-based fuels, through a hydrogen-generating device, for use in diesel cycle engines, meeting at least 3 of the following parameters:
In a preferred version, the hydrogen generator and injector device for diesel cycle engines of this invention is characterized by meeting at least 4 of the following parameters:
In an even more preferred embodiment, the hydrogen-generating device for combustion engines of this invention is characterized by meeting each of the following parameters:
The device of this invention is preferably composed of the following parts:
The electronic module ensures that the system only turns on when the engine is running, controls the energy to be supplied to the system so that hydrogen production is consistent with operational demand, and promotes periodic changes in the polarity of the electrodes to optimize their use and useful life.
The foundations that support the operation of this invention are based on the use of an adequate amount of hydrogen to be injected into the intake air to optimize combustion in diesel cycle engines. This aims to produce a series of micro hydrogen explosions, which contribute to homogenizing the fuel mixture and standardizing dispersion in the combustion chamber, without consuming significant parts of the oxygen necessary for the combustion of hydrocarbons.
Because it has a lower ignition temperature than diesel, hydrogen explodes a little before it. However, since the quantity of hydrogen is adequate, its explosion does not consume a significant amount of oxygen from the fuel mixture, as would occur if the hydrogen concentration were higher. Thus, with the high diffusion speed of its flame, there is greater homogenization of the fuel mixture (diesel oil and oxygen) and greater uniformity of its distribution throughout the chamber. This is intended to provide more complete combustion, with greater conversion of thermal energy from the fuel into driving force and, consequently, lower emission of polluting gases, soot and partially oxidized compounds in general.
In order not to compromise the useful life of the alternator/battery assembly, the device of this invention must not consume more than 3 Watts/liter of diesel oil consumed by the engine.
By promoting an optimization of combustion in diesel cycle engines, there is less formation of combustion residues, thus reducing contamination of the lubricating oil. In other words, the device of this invention can also provide an increase in the lubricating oil change period and engine durability.
An example is provided below to better characterize the scope of the invention, and it should not be used for limiting purposes of the invention.
Tests were performed on 8 different diesel engines, equipped with one or more hydrogen generator/injector devices, according to this invention. The devices used were the same, sized for engines of up to 400 hp and consumed up to 12 Watts/hour each, according to the engine's operating conditions, captured by the electronic control module of the devices tested. Depending on the power of the engine tested, one or more devices were used, so that each device met up to 400 hp of the engine's capacity.
The installations in the vehicles were made using a hydrogen-generating and pollutant emission-reducing device characterized by:
Table 1 indicates the equipment tested WITHOUT and WITH the device according to the invention (GF). Table 1 also shows the volume and power specifications of each engine, as well as the type of use for which it was intended. The table also informs the duration, in kilometers driven or machine hours worked, of use of the engines WITHOUT and WITH the activation of the device of this invention (GF), in order to produce statistically reliable results for comparison. Finally, the table shows the diesel and hydrogen consumption of the engines during the test period.
The results in Table 1 show that engines M1 to M5 were installed in commercial trucks from a fleet used to transport tractors and tow trucks for automobiles. Engine M6 was installed in a loader of a mining company and engines M7 and M8 were stationary engines.
Table 2 shows the amount of hydrogen that was injected per liter of diesel consumed in each engine, during the period in which it was tested with the device of this invention activated. From the results presented, it can be observed that the injection of hydrogen, per liter of diesel consumed, varied from 1% to 8%, in volume/volume.
Table 2 also shows that the energy consumed by the device of this invention varied from 0.2 to 2.2 Watts/liter of diesel consumed by the engine when operating with the device (GF) activated. Engines M1 to M6 were tested with only one device installed, while engines M7 and M8 were tested with 4 devices installed.
indicates data missing or illegible when filed
Table 3 shows the reduction in diesel consumption and pollutant emissions, measured by opacity, by the engines tested, when operating with the devices of this invention activated.
The results presented in Table 3 show that the reduction in diesel consumption ranged from 4.1% to 17.5% when operating with the devices of this invention (GF) activated. Factors such as the type of work performed and the technological modernity of the engines are factors that certainly explain the variations in consumption reduction observed. However, all the engines tested showed economically significant reductions in diesel consumption, which makes the use of the device of this invention viable.
Table 3 also shows significant reductions in particulate pollutant emissions when each engine operated with the device activated. These emissions could be measured by varying the opacity of the emissions. The results presented in Table 3 show that the reduction in particulate pollutant emissions ranged from 40 to 98%. This is highly significant.
Although it is difficult to assess the economic return on reducing particulate pollutant emissions, there is no doubt that this is an environmental need and would justify the requirement for a green patent for this invention. This invention characterizes a device capable of reducing fuel consumption and mitigating pollutant emissions in diesel cycle engines.
Analysis of the outlet gases and operating conditions of the electrolyzers.
The chemical composition of the mixture of outlet gases from the electrolyzers covered in this example was evaluated.
These devices were individually connected to three voltage sources for 406 uninterrupted hours. The gas composition was determined by using a gas chromatograph model 310C from SRI Instruments. The samples were analyzed by a TCD detector after passing through a Molecular Sieve 5A column for gas separation, at a temperature of 60° C. For each sample, 50 μL of the gas generated inside the reactor was collected using a chromatographic syringe. To correlate the peak area of the chromatogram for each identified gas with its respective number of moles, calibration curves were constructed by injecting known volumes of gases with a purity of 99.999%. The gases used were: a mixture of 7% H2 in Ar and synthetic air (20% O2+80% N2), both with purity grade 5.0 (99.999%), obtained from White Martins. Additionally, the cells were monitored for input current at the source, output current at the electrolyzer and potential applied between the electrodes.
The morphology and relative chemical composition of the electrode surfaces were investigated by using a JEOL Scanning Electron Microscope (SEM) model JSM-6380LV and a Thermo Scientific Energy Dispersive X-ray Spectroscopy (EDS) system model Noran System Six coupled to the SEM. The steel electrodes were investigated immediately after the 406-h stability test.
Analysis of the outlet gases and operating conditions of the electrolyzers
The electrolyzers were monitored in constant operation for a period of 406 hours.
The input and output currents (experienced by the electrodes) were also monitored as a function of time, as illustrated in
In addition to the electrical operating properties, the electrolyzers were evaluated for the gases produced as a function of time. Measurements of the gas composition were taken every 24 h for a total period of 406 h.
For comparison purposes,
The composition of the gas mixture can also be interpreted by the H2/O2 molar ratio, as shown in
As shown in scanning electron microscopy (SEM) analyses, before being used for electrolysis, the electrode presented a flat, dense and uniform surface with some parallel scratches generated by the machining process, as shown in
From the EDX spectrum (
Table 4, below, shows the chemical elements and their atomic proportions found on the electrode surface before and after electrolysis:
Table 5, below, presents the comparative ratio between the steel constituent elements (Fe, Cr, Ni and Mo) of the electrode before and after electrolysis.
After investigating the electrolyzer components, the electrolyzer's operation on the bench and its applications in different vehicles, the system was validated by a reputable and unblemished company in the automotive sector, Netz. Using the SAE J1321 Standard—Fuel Consumption Test Procedure—Type II, the difference in fuel consumption related to the use of the Green Fuel equipment was determined. The measurements were made by using two identical Iveco Stralis Hi Way 600S44T (6×2) tractor trucks and their respective semi-trailers weighted at their nominal PBTC condition.
One vehicle called the Test vehicle was equipped with Green Fuel technology and the second, the Control vehicle, with the original factory configuration. The main technical characteristics of the Test and Control vehicles are presented in Table 6.
The two vehicles ran simultaneously during the tests, in a back-to-back situation in compliance with the requirements of SAE J1321 Standard, so that the Control vehicle could serve as a baseline for calculating the fuel consumption of the Test vehicle with and without the Green Fuel equipment activated. All test runs were performed with the vehicles in running order, considering the following conditions: full fuel tank; water and Arla 32 tanks filled; spare tire; tools; and Driver. Each of the vehicles had a Netz Technician present during all runs, as an Observer, in order to assist the Drivers in standardizing the laps and batteries.
Aiming to obtain results closer to a road operation, the basic loading condition simulates the vehicle's nominal GCW. The ballast was operated by means of loaded 2,700 ft3 containers. Beviani Transportes, the company that supplied the vehicles for testing, reported the following weights for each set: Test Set: 42,460 kg; Control Set: 43,240 kg.
The test was conducted on public highways between the cities of Balneario Picarras, Barra Velha and Penha, all in the state of Santa Catarina. Sections of Highway BR-101 (Governador Mario Covas Hwy.) and João Batista Sérgio Murad Hwy. were used.
The dynamic control of the runs was carried out in order to ensure repeatability and uniformity in the driving style in each cycle and in each set of batteries. The fuel was refueled at the end of each set of batteries, together with the weighing of the additional fuel tank. The operation of the vehicles was controlled by the Driver under the guidance of Netz's Technician, using the vehicle's cruise control to accelerate and maintain constant speeds on the straights of the track.
The “Constant Speed” methodology was adopted to meet the test evaluations. The runs consisted of seeking a constant speed of 70 km/h, in order to obtain an average operating speed of 58 km/h, compatible with the road operations of the company supplying the vehicles, Beviani Transportes. Each set of batteries consisted of 60.9 kilometers traveled on the round trip between the selected points.
The criterion selected for measuring fuel consumption was gravimetric analysis. Measuring fuel consumption by weighing the fuel is the most effective method due to the accuracy of the scale used and the exclusion of the temperature factor in the measurement. The weight of the fuel consumed is recorded after each battery run, for a total of three valid measurements for each Green Fuel condition: active or inactive. The vehicle was equipped with a 55-liter auxiliary portable tank. The fuel supply and return lines were removed from the vehicle's organic tank and temporarily connected to the auxiliary tank.
A small 10-liter auxiliary tank was used, similar to the fuel model, so that Arla-32 consumption measurements could be made. A NetzLog device was used to read the vehicle's CAN line and record engine operating parameters in a datalog, such as: rotation, speed, torque, acceleration and operating temperatures, at a rate of 1 second between each recording. The equipment also has a GPS location and tracking system, which is connected directly to the vehicle's OBD socket. A Racelogic V-Box, a performance navigator, was also used to measure and control acceleration and deceleration.
Throughout the test, the vehicles used S-10 Diesel fuel. Refueling took place at a commercial gas station located at km 103 of BR-101, in Balneário Piçarras, which was selected as the test base.
Every day, before the start of the tests, all tires were calibrated to 120 psi. The tires had their measurements controlled to ensure a service life of over 80%. The vehicle windows were kept closed throughout the test. Cruise control was used to maintain a constant speed of 70 km/h.
The fuel consumption comparison between the test vehicle with Green Fuel active and inactive was calculated for the tested speed of 70 km/h, by using the SAE J1321 Standard. Table 7 presents the driving information and calculation of the differences in fuel consumption, for the 70 km/h cycle, between the active and inactive Green Fuel situations. The Test vehicle with Green Fuel Activated presented a fuel consumption, by weight, 3.6% LOWER than the Test vehicle with Green Fuel Inactive.
Regarding the consumption of Arla 32, Table 8 shows the driving information and calculation of the differences in consumption for the 70 km/h cycle, between the active and inactive Green Fuel situations. The Test vehicle with the Activated Green Fuel presented an Arla 32 consumption, by weight, 4.9% LOWER than the Test vehicle with the Inactive Green Fuel.
It can be concluded that the comparative results for the 70 km/h cycle, suitable for highway operation, showed that the Test vehicle with the Green Fuel Electrolyzer active presents a fuel consumption, by weight, 3.6% LOWER than the inactive Green Fuel.
The consumption of Arla 32, by weight, was also 4.9% LOWER with the active Green Fuel, however, the standard deviation of each sample set was much higher than the limits allowed by the Standard. Such a result may demonstrate a trend but should not be assumed in an absolute way. It is important to emphasize that this is a secondary measurement report. The specific methodology for measuring Arla 32 consumption should be discussed in the case of greater accuracy required.
As mentioned above, at the end of an operating period, the electrolyte containing suspended particulates comprises the system residue. In order to understand the effects of the residue on the environment, an analysis of environmental toxicity assessment data was performed by using the Allium cepa test. In general, the Allium cepa test is widely recognized and recommended by several national and international organizations as an effective tool for assessing the genotoxicity of chemicals and environmental pollutants. For example, bioassays using Allium cepa roots are validated by the International Program on Plant Bioassays (IPPB) and the United Nations Environment Program (UNEP) as an efficient test organism for “in situ” analysis and monitoring of environmental contaminants [Mutation Research, 426 (1999) 103-106].
Allium cepa assays were performed using pesticide-free seeds. For each group studied, 120 seeds (3 subgroups of 40) of Allium cepa were placed in Petri dishes with a layer of filter paper, and were continuously exposed to the undiluted residue (hereinafter referred to as “X”) and to the residue diluted in water at different concentrations (in “X/10”, “X/100” and “X/1000” dilutions). Additionally, other groups of seeds were exposed to two control solutions: (i) positive control (PC), which was exposed to Trifluralin, a known mutagenic chemical agent; and (ii) negative control (NC), to distilled water, a non-toxic agent. Initially, 3 mL of the tested solutions were added to each Petri dish and, subsequently, another 1 mL was added after 48 h. Consequently, 6 groups were investigated (CN, CP, X, X/10, X/100 and X/1000), totaling 720 seeds analyzed. As represented in
During the bioassays, the seeds were placed in a germination and growth chamber, type B.O.D, with temperature control of 25° C., humidity of 80+5% and photoperiod of 12 h for 120 h. After this period, the Germination Index (GI) and the Mean Root Length (MRL) were determined. Subsequently, the roots of the germinated seeds were fixed (Carnoy's solution, alcohol solution and acetic acid in the ratio of 3:1 (v/v)). After 8 h of fixation, the Carnoy's solution was replaced by a new one, where the seeds remained until the slides were prepared. Subsequently, the roots underwent the washing process five times with distilled water in order to remove the Carnoy's solution. Then, by acid hydrolysis with 1 M HCl at 60° C. for 10 minutes, and then they were washed repeatedly again with distilled water. In addition, they were immersed in Schiff's reagent solution and the tubes were protected with aluminum foil to avoid contact with light.
To prepare the slides, the meristematic regions of the Allium cepa roots were collected and sectioned with a scalpel and placed on a glass slide, and then a drop of 45% acetic Carmine was added, covered with a coverslip and carefully crushed. For each sample, 5 slides were prepared, and then images of the cells were collected with the aid of a Nikon optical microscope, with a magnification of 40×. For each slide, 1,000 cells were observed and analyzed, totaling 5,000 cells per sample, with the aid of the ImageJ program. During this analysis process, the cells were checked and cataloged between the different cell types, divided into interphase and normally dividing cells, as shown in
Regarding cellular analyses, the results showed that none of the treatments altered the MI (
Finally, the findings also showed that only the water (CN) and residue samples diluted a thousand times (X/1000) did not present cell death, as shown in
Based on the results presented and the analyses of the germination, root growth, mitosis, micronucleus, chromosomal abnormalities and cell death rates, it is concluded that the sample has a harmful potential in case of direct disposal into the environment, as demonstrated by the inhibition of germination and observations of genotoxic and mutagenic alterations. However, the results also demonstrate that when an adequate dilution is performed, it is possible to obtain a diluted solution of the residue that does not present environmental toxicity through the Allium cepa test. This was obtained when the residue was agitated and subsequently diluted in water in a 1:1000 ratio of residue to water. In this context, disposal in the sewage system seems appropriate due to the dilution of the system itself.
Gas generation performance measurements of real cells and those in continuous operation were analyzed, as well as exploratory measurements of the morphology and elemental chemical composition of the electrodes. In general, the electrolyzers presented stable performance aiming at the production of H2 and O2 for administration in Diesel cycle engines.
After analyzing three electrolyzers in operation for 406 hours, we identified constant production of gases with a majority composition of H2; with an average composition in molar percentage of 60:40 of H2:O2. This result shows that both electrodes of the cell function well both as anode and cathode during the periodic alternation of polarization of the system.
Microscopic investigation of the electrode shows a thick film composed of agglomerates on its surface after 406 hours of operation. The energy-dispersive X-ray spectra obtained from scanning electron microscopy show intense corrosion, with an increase in oxygen and a significant decrease in the amounts of iron, chromium and nickel in the surface chemical composition of the electrode. However, this corrosion did not affect the production and composition of the gases.
The 70 km/h vehicle validation test, suitable for road operation, showed that the Test vehicle with the Green Fuel Electrolyzer active presented a fuel consumption, by weight, 3.6% LOWER than that with the Green Fuel inactive. Additionally, the consumption of Arla 32, by weight, was also 4.9% LOWER with the Green Fuel active, however, the standard deviation of each sample set was much higher than the limits permitted by the Standard. This result may demonstrate a trend but should not be assumed in absolute terms with regard to Arla.
Phytotoxicity tests performed on electrolyzer residues after a cycle of use showed that the residue needs to be diluted in water to avoid toxicity. It is suggested, therefore, that the material be discarded in water or even in the sewage system, to induce the residue to dilute.
| Number | Date | Country | Kind |
|---|---|---|---|
| 102022004276-4 | Mar 2022 | BR | national |
This application is the United States national phase of International Patent Application No. PCT/BR2023/050078 filed Mar. 8, 2023, and claims priority to Brazilian patent application Ser. No. 102022004276-4 filed Mar. 8, 2022, the disclosures of which are hereby incorporated by reference in their entireties.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/BR2023/050078 | 3/8/2023 | WO |
