Concrete truckmixer powered by hydrogen slave engine

Abstract

"Concrete Truck-Mixer Powered by Hydrogen slave engine" is a vehicle mounted concrete Mixer (1) operated by means of a dedicated slave engine (3) which is an Internal Combustion Engine using Hydrogen gas as fuel and the said equipment is also provided with an emergency on- board Hydrogen Generator (5) which gives alternative supply of Hydrogen in case the main fuel storage is exhausted.

Description

TITLE OF THE INVENTION:“Concrete Truck-Mixer powered by Hydrogen Slave Engine”

[0001] TECHNICAL FIELD:This invention specifically relates to a Vehicle or Truck mounted Mobile Concrete Mixer which is not operated by the vehicle engine but by essentially is operated by means of an independent dedicated slave engine which is smaller in capacity than the Vehicle engine.In particular this invention does not relate to the chemistry of hydrogen burning and hydrogen production method but specifically relates to the mechanical construction of the equipment and the apparatus.

[0002] BACKGROUND ART:The vehicle mounted mobile concrete production and transportation equipment have been in existence for quite some time now and can be classified into various types depending upon their operating mechanism such as Weight based, Volume Based and a combination of weight and volume.These Vehicle Mounted Mobile Concrete Production & Transportation Equipment are provided with a plurality of separate material compartments for DRY bulk materials on the top and two or more tanks for liquid additives such as water and chemical additives. These equipment are provided with a batch type or Continuous Mixer to mix concrete at site by adding water & chemical additives.Our granted Indian Patent No. 287080, legally in force & commercialized, discloses a fully automatic concrete mixer which is installed on a rigid Truck chassis and is operated by means of an electric drive taken from an alternator coupled with a Truck PTO. Alternatively the equipment is operated by means of a dedicated slave engine using diesel fuel by hydraulic or electric means. iSUBSTITUTE SHEET (RULE 26)Our second granted Indian Patent No. 327661, legally in force & duly commercialized, discloses a fully automatic concrete mixer installed on a commercial Truck and having a custom designed Mixer wherein the machine is driven by means of a PTO drive or alternatively by a dedicated slave engine.Our Third granted Indian Patent No. 323780, legally in force, discloses a SCMD Transit Mixer installed on commercial Trucks essentially operated by means of small dedicated diesel slave engines.Our Fourth granted Indian Patent No. 395657, legally in force and duly commercialized, discloses a fully automatic mobile Concrete Mixer installed on a commercial Truck having VWT batching also typically uses a dedicated slave engine which is a Four Cylinder Air cooled Diesel engine.The above four separate granted patents therefore collectively represent the PRIOR ART No. 1 , wherein a Mobile Concrete Mixer having at-least one Mixer for mixing concrete & a water tank and the said mixer is powered by means of a dedicated Slave engine which typically uses Diesel fuel for its operation.The conventional Transit Concrete Mixer which has a rotating Mixing Drum is the PRIOR ART NO. 2, which is provided with a reversible Drum Mixer, a water tank and is typically operated by means of a dedicated slave engine which typically uses diesel fuel.It is needless to say that the use of fossil fuels such as diesel have been causing a Huge amount of city air pollution and a Huge Carbon foot print.Over the years the number of Truck- Mounted Concrete Mixers have gone up exponentially and thousands of such concrete mixers ply in and out of the cities causing air pollution and Green House gases.2SUBSTITUTE SHEET (RULE 26)

[0003] TECHNICAL PROBLEM ASSOCIATED WITH THE EXISTING PRIOR ARTS:The Prior art No. 1 which is collectively represented by our granted patents alternatively use dedicated slave engines which work on diesel fuel. Though the set of equipment as represented by the said PRIOR ART NO. 1 do not use the dedicated engines continuously but use them only when the Trucks on which they are installed are stationary. So these slave engines operate only when concrete is actually produced. However in comparison, the Prior Art No. 2 uses diesel engines continuously. Especially the concrete Transit Mixers represented by the Prior Art No. 2 are widely used to transport wet concrete from one location to another.Especially the problem is much bigger with the Concrete Transit Mixers due to the following reason:These Transit Concrete Mixers are fitted with diesel engines which do not fall under automotive vehicle emission norms because a concrete mixer in India has been specified as a Construction Equipment to which the Vehicular pollution norms are not applicable.Its very important to note here that it simply means that though the Truck engine is BS-6 Compliant, the slave diesel engine does not comply to BS-6 norms. Now when we particularly look at the Transit Concrete Mixers which are widely used all over India and thousands of such Concrete Mixers are plying in and out of our cities, there is a huge air pollution caused by the slave engines burning diesel to keep the wet concrete alive by rotating the drum continuously.Kindly refer to the Fig. No. 1 on sheet No. 1 which shows a Transit Concrete Mixer having a rotating drum mixer (1) and a water tank (2) which are the most identifiable components apart from the dedicated slave engine (3).The said dedicated slave engine (3) is a BS-3 or BS-4 Compliant engine However the Truck Engine is BS-6.3SUBSTITUTE SHEET (RULE 26)Further in order to keep the wet concrete ALIVE, the said engine has to operate continuously in loaded transit and has to rotate the DRUM continuously which needs huge amount of power. Typically the dedicated slave engines used by 6 cubic meter capacity transit mixers are 4 cylinder, air cooled diesel engines having a power rating of 42 to 49 KW (56 to 65 HP). These engines consume from 4 to 8 liters of diesel fuel per hour depending upon their loading. Therefore we can imagine how many lacs & lacs of liters of diesel fuel are burnt all over India by thousands of such machines operating 10-12 hours a day and 25 days in a month.The problem is much bigger since these vehicles ply in urban areas and congested city areas where the common citizen is completely exposed to the deadly diesel fuel pollution caused by such heavy vehicles having 56-65 HP slave engines not confirming to BS-6 norms.Further the very high diesel consumption means very high import bills for a country like India. The slave engines are therefore causing maximum damage to the city atmosphere and most importantly cause Particulate matter pollution such as PM 2.5 which is deadly and this results in deterioration of the city and urban atmosphere.So the problem especially with the equipment represented by the PRIOR ART No. 2 is Huge and there has to be a solution to the same as early as possible.

[0004] OBJECT OF INVENTION:The primary object of the present invention is thus to reduce the air pollution by Huge margin which is being caused today by any type of Truck-mounted concrete Mixer having a Mixer and a water tank and powered by a dedicated slave engine using a fossil fuel such as diesel and the said engine is below the automotive norms of BS-6. Especially the Prior art No. 2 represented by Transit Concrete Mixers as shown in the Fig. 1 on sheet No. 1 wherein the said Mixers typically use high power diesel engines.4SUBSTITUTE SHEET (RULE 26)Another important objection of the present invention is to retain the basic construction of the equipment so as to only reduce the damaging effect of the diesel fuel burning day in and day out to keep wet concrete alive.Another object of the present invention is to completely eliminate the carbon foot-print associated with concrete transportation.Another important objective is to have a concrete transportation equipment which is eco-friendly and most importantly citizen friendly so as to relieve the common citizen residing inside urban localities and congested areas.Another important objective is to cut down the import cost of fossil fuels such as diesel fuel thereby on a macro scale making a huge difference to the country's trade deficit.Another very important objective is to have a concrete transporting equipment which does not cause any carbon pollution and is useful in order to achieve the climate change targets.Another important objective is to have an emergency mechanism to ensure that the concrete mixer can be emptied in case the fuel is exhausted.Therefore there has been no alternative but to use a dedicated slave engine for operating the mobile concrete mixer which uses a clean fuel like Hydrogen. The Hydrogen gas is a unique fuel which produces water as exhaust and therefore completely eliminates the carbon foot-print associated with the concrete transportation. However the Concrete Mixer is a tricky piece of Equipment as concrete itself is a tricky material to transport and though Hydrogen can be used in custom designed IC engines with modifications taking into consideration the difference in Auto ignition temperatures, it remains a challenge to have Hydrogen fuel available everywhere. And in case if the mixer is having concrete inside, there also needs to be an on board hydrogen generator which can safely generate the Hydrogen fuel on board so as to unload the5SUBSTITUTE SHEET (RULE 26)concrete mixer completely even when the Hydrogen fuel is completely exhausted.Therefore the only effective solution to the above issue is to have an Internal Combustion Engine using Hydrogen fuel only for the Concrete Mixing Equipment while the Truck Engine can be still BS-6 diesel engine. This is a very practical invention because the use of Hydrogen as fuel will take huge amount of transition time considering the challenges in production and distribution of hydrogen. Therefore there is also a need of an alternative on-board hydrogen generator which can generate Hydrogen Fuel in the purest form without having the need to use very high pressure gas storage and thus the industry need not wait for the Hydrogen gas supply and distribution challenges are met.However, having said that, the hydrogen engine for Concrete transportation equipment is very much required & is a necessity because the concrete transporting activity is not only fossil fuel intensive but also has huge damaging effect on air quality and city atmosphere.As it is well known, getting an Internal Combustion Engine to run on Hydrogen is not difficult. However having alternative sources of Hydrogen fuel is a much bigger problem.This invention therefore not only offers a practical solution to the biggest pollution problem faced by the Concrete transport Industry and the common people who are subjected to deadly diesel pollution which is not compliant with BS-6 norms. It will take huge amount of time to actually have a complete vehicle running on Hydrogen or any other fuel other than fossil fuels or even for that matter electric batteries because of the very high power requirement of the Concrete Transport Industry. However on the other hand small slave engines using Hydrogen as fuel is a reality and the only practical solution is to start using the IC engines using Hydrogen as the slave engines with Vehicles powered by BS-6 engines immediately. However concrete is a tricky material to transport and when using a new fuel like hydrogen there has to be an emergency availability of hydrogen fuel even in remote areas and6SUBSTITUTE SHEET (RULE 26)hence there needs to be an alternative source of Hydrogen right on the vehicle.Therefore the present invention not only addresses the big issue of air pollution caused by non-compliant slave engines presently in rampant use but also effectively addresses the emergency requirement of clean fuel on board of the vehicle while using a fuel which is yet not available everywhere like the fossil fuels.History of Hydrogen Engines:The first Hydrogen engine was made in 1820.As said earlier, getting an IC engine to run on Hydrogen is not difficult. The earliest attempt at developing a Hydrogen engine goes to the credit of Reverend W. Cecil in 1820. In 1820, Mr. Cecil presented his work before the Cambridge Philosophical Society in a paper entitled "On the Application of Hydrogen gas to produce moving power in Machinery". The engine itself operated on the vacuum principle, in which atmospheric pressure drives a piston back against vacuum to produce power. The vacuum is created by burning a Hydrogen-Air Mixture, allowing it to expand and then cool. Although the engine operated satisfactorily, the vacuum engines never became practical.Sixty years later, in 1860-1870; N.A. Otto, the inventor of the Otto cycle reportedly used a synthetic producer gas for fuel which was believed to have a hydrogen content over 50%.Hydrogen has since been used extensively in space programs since it has the best energy to weight ratio of any fuel. Liquid Hydrogen is an ideal fuel for rocket engines and has been used in upper stages of launch vehicles on many space missions.In recent years, the concern for Cleaner Air along-with stricter air pollution norms and the desire to reduce the dependency on fossil fuels such as diesel and petrol has generated a new interest in use of Hydrogen gas as a fuel.Properties of Hydrogen in terms of use as a fuel:7SUBSTITUTE SHEET (RULE 26)The properties of Hydrogen that contribute to its use as a combustible fuel are:Wide range of flammabilityLow energy of ignitionSmall quenching distanceHigh auto-ignition temperatureHigh flame speed at stoichiometric ratiosHigh diffusivityVery low Density.Wide range of flammability:Hydrogen has a wide flammability range in comparison with all existing fuels. As a result Hydrogen can be combusted in an Internal Combustion Engine over a wide range of fuel-air mixtures. A very important advantage of this is that Hydrogen can run on a lean mixture. A lean mixture is one in which the amount of fuel is less than the theoretical, stoichiometric or chemically ideal amount needed for combustion with a given amount of air.This is why it is fairly easy to start an IC engine on Hydrogen.Also the fuel economy is greater & the combustion reaction is more complete when the vehicle is run on a lean mixture. Additionally the final combustion temperature is also lower reducing the amount of pollutants such as NOX emitted in the exhaust. However there is a limit to how much lean mixture can be used as leaner the mixture lower is the power produced.Low energy of Ignition:Hydrogen has very low ignition energy. The amount of energy needed to ignite Hydrogen is about one order of magnitude less than that required8SUBSTITUTE SHEET (RULE 26)to ignite Petrol. This enables IC engines using Hydrogen to ignite lean mixtures and ensures prompt ignition.Small quenching distance:Hydrogen has a smaller quenching distance than Petrol. Hydrogen flames travel closer to the cylinder walls than other fuels before they are quenched.High Auto-Ignition Temperature:Hydrogen has a relatively high auto-ignition temperature. The Autoignition temperature is an important factor in determining what compression ratio the engine can use, since the temperature rise during compression is related to the compression ratio.The temperature may not exceed the auto ignition temperature of Hydrogen gas without causing pre-mature ignition. Thus the absolute final temperature limits the compression ratio. The high auto ignition temperature of Hydrogen therefore allows larger compression ratios to be used in a Hydrogen IC engine than in a engine using a hydrocarbon fuel.This higher compression ratio is important as it is related to the thermal efficiency of the engine. On the other hand Hydrogen is difficult to ignite in a compression ignition like the diesel engine. This is because of the high auto-ignition temperature. Therefore the Hydrogen engine has to be custom made or custom modified keeping in view this important property of Hydrogen.High flame speed:Hydrogen has high flame speed at stoichiometric ratios. The Hydrogen flame speed is higher than Petrol. Which means that Hydrogen engine can more closely approach the thermodynamically ideal engine cycle.High Diffusivity:Hydrogen has a very high diffusivity. This ability to disperse in air is considerably greater than Petrol & Diesel and is beneficial for two reasons. Firstly it facilitates the formation of a uniform air fuel mixture. Secondly9SUBSTITUTE SHEET (RULE 26)in case of any accidental leakage, hydrogen disperses rapidly thereby avoiding or minimizing risk.Low Density:Hydrogen has very low density which results in two problems when used in an IC engine. Firstly a very large volume is needed to store enough hydrogen to give the engine an adequate range. Secondly the engine has to be little bigger to compensate for the power output.However when we use Hydrogen engine, the availability of Hydrogen is a matter of concern as the Green hydrogen which is generated by using an electrolyzer by separating Hydrogen and oxygen from water needs to use only the electricity which is essentially produced by means of renewable sources. Therefore Green Hydrogen alone will not be able to immediately suffice for all the fuel needs. And it will take a huge amount of time to develop the manufacturing & distribution network of Green hydrogen.Conventional Concrete Transit Mixers as shown in the Fig. No. 1 on sheet No. 1 as the prior art are provided with a rotating drum which transports wet concrete from one location to another. Wet Concrete is also a tricky material which sets quickly in case the drum rotation stops for variety of reasons. The hydrogen tanks are high pressure tanks to store higher amount of Hydrogen gas. However the Concrete mixers need huge amount of power approximately 56 to 65 Hp slave engines which consumes 4 to 5 liters of diesel per hour. Since the Hydrogen storage in tanks is limited due to many reasons and if 6 to 10 kg capacity Hydrogen tanks are provided, there might be insufficient fuel and frequent refilling may be needed. Since it will take a long time to have the distribution network like petrol & diesel, there also needs to be some emergency supply of Hydrogen fuel on board sufficient enough to operate the Mixer to empty the concrete in such situations.

[0005] SUMMARY OR DISCLOSURE OF THE INVENTION:"Concrete Truck-Mixer powered by Hydrogen Slave Engine" is characterized by-10SUBSTITUTE SHEET (RULE 26)A vehicle mounted Mobile Concrete Equipment having at least one Mixer (1) and a water tank (2) wherein the said mixer (1) is not operated by the Vehicle engine PTO but is operated by means of a dedicated slave engine (3);Wherein the said dedicated slave engine (3) is adapted to use Hydrogen gas as its primary fuel and is adapted to have a suitable capacity high pressure hydrogen gas storage cylinder (4) installed on the vehicle chassis.An emergency on-board Hydrogen generator (5) which is adapted to produce Hydrogen in a safe and automatic way so as to operate the concrete Mixer when the main storage cylinder (4) is exhausted;A selector switch to change the fuel supply between the main fuel tank (5) and the on-board tank (6) adapted to be filled by the said emergency on-board Hydrogen Generator.Since the Hydrogen fuel differs in many ways when compared to a diesel engine, the engine is adapted to be redesigned by keeping in view the properties of Hydrogen fuel as discussed earlier. A few very important points as follows:The basic problem with Hydrogen engines is pre-mature ignition because of the low ignition energy of Hydrogen. It happens when the air / fuel mixture in the combustion chamber becomes ignited before ignition by the spark plug which may result in an inefficient and rough running of the engine. Therefore the engine is adapted to be designed to avoid preignition by means of any hot spots or by suspended lubrication oil or by means of blow-by from crankcase.Re-designed fuel delivery systems, are also adapted to eliminate preignition.The fuel delivery system can be adapted by means of carbureted or port injection of direct injection in the chamber. Central or carbureted injection the injection is at the inlet of the air intake manifold. In the case of port injection, it is injected at the inlet port. However the direct injection involves forming the air-fuel mixture inside the combustion cylinder after air intake valve is closed. iiSUBSTITUTE SHEET (RULE 26)However the simplest methods include using a simple carburetor or central injection system. This has advantages especially in case of Hydrogen. First, it does not need high Hydrogen supply pressure, second, it is much easier to convert existing Petrol engines to Hydrogen engines.The hydrogen engine is adapted to use cold rated spark plugs so as to avoid any un-wanted ignition by the hot tip.The said engine is alternatively adapted to use a direct injection method though the simplest method is to use a carburetor or central injection in order to avoid pre-ignition in the intake stroke also the engine cannot backfire into the intake manifold.Due to the high diffusivity of Hydrogen, Hydrogen can diffuse into the crankcase and there can be a sudden pressure rise inside the crankcase due to ignition of hydrogen. The same is avoided by having an effective crank case ventilation.Accordingly a custom designed Hydrogen IC engine is provided.The Main Hydrogen storage Cylinder (4) is provided to have suitable capacity Hydrogen gas under high pressure. Since the Hydrogen fuel is not available everywhere, an on-board hydrogen generator (5) is adapted to produce Hydrogen depending upon the gas pressure inside the main storage tank (4).The on board Hydrogen generator (5) is characterized by: a custom designed solid material compartment (7) is adapted to have a small screw conveyor (8) at its bottom, adapted to operate by means of a small DC motor (9) operable by the vehicle battery; wherein the said solid material compartment (7) is installed on top of a liquid material compartment (10) in such a way that the said screw conveyor (8) is adapted to convey a pre-determined fixed flow of the solid material into the liquid material compartment (10) per each rotation of the screw (8);12SUBSTITUTE SHEET (RULE 26)the said liquid compartment (10) is also adapted to operate as a reaction chamber as the reaction is adapted to start by virtue of the screw conveyor (8) rotating & conveying the solid material into the liquid compartment (10); a DC compressor (11) is adapted to start along-with the said DC motor (9) and suck the gas produced in the liquid compartment (10) after the signal from pressure sensor (11) is received and is adapted to fill the another gas storage cylinder (6) wherein the said gas cylinder (6) is adapted to have another pressure sensor (12) pre-set with the maximum allowable pressure in the cylinder and is adapted to switch off the DC motor & the DC compressor once the preset pressure is reached so as to stop the gas production automatically;The said liquid compartment is provided means to add the liquid material & remove the products after consumption of the solid material.The solid material used is powdered Aluminum & the liquid material used is aqueous NaOH solution. Aluminum is anyway widely made and easily available along with caustic soda (NaOH) and aluminum scrap is easily available at low price where the current scrap price is Rs 105 per Kg even in retail.The only by-product Sodium Aluminate has many commercial applications as it is already being specially made and sold commercially and the selling cost of sodium aluminate is very high and therefore the overall cost of Hydrogen as fuel will be less than many other sources of Hydrogen. The by-product is collected at the time of re-filling and is processed and sold.It is important to note here that-The 1 kg Hydrogen production Model needs the following materials- : 8.92 kg of Aluminum, 13.22 kg of NaOH and 5.95 liters of water. In the process it produces 1 Kg Hydrogen and 27.10 Kg of Sodium Aluminate.13SUBSTITUTE SHEET (RULE 26)At current retail rates in Pune India as on date in INR -Rate of Al scrap: Rs 105 per KgRate of caustic soda in Pune: Rs 40 per KgRate of water per liter: Rs 1 per literSo the total input cost per Kg Hydrogen production is = 936.60 + 528.80 + 5.95 = 1471.35However the current rate of Sodium aluminate is between Rs 52 to Rs 100 depending on suppliers. Assuming the lowest cost which is Rs 52 per Kg, we have 27 Kg sodium aluminate worth Rs 1404.So the overall cost of 1 Kg Hydrogen is only Rs 67.35 (less than 1 dollar) which is much cheaper compared to any other method of Hydrogen production.Market Overview:The global sodium aluminate market is projected to grow from USD 1.02 billion in 2017 to USD 1.48 billion by 2030, at a CAGR of 4.5% from 2017 to 2030. The growth of the global sodium aluminate market can be attributed to the increasing demand for paper products, water treatment, cement additives, and the titanium dioxide industry across the globe.Paper industry was the largest application segment in 2015, accounting for over 50% of the global sodium aluminate market. The product is used as a pulp refiner and papermaker's agent. It improves the brightness, opacity and sheet resistance of the paper produced through chemical and water treatment processes.The product is also used in various applications such as bleaching powder, filler for newsprint, tissue former and pulp slurry feedstock14SUBSTITUTE SHEET (RULE 26)for kraft paper production. In addition to this, it finds application as an anti-scaling agent in hot press printing ink where it helps prevent scaling by forming a protective film on ink particles that prevents them from adhering to each other or fabric when exposed to water or moisture during washing or drying cycles at high temperatures commonly found in textile printing plants.The Asia Pacific was the largest market for sodium aluminate and accounted for over 50% of the global revenue in 2015. The presence of a large number of manufacturers coupled with rising demand from end-use industries such as paper, water treatment, and cement additives is expected to drive growth over the forecast period.The industry in the Asia Pacific is characterized by high production levels along with rapid expansion plans from domestic manufacturers looking to cater to growing regional demand. In addition, increasing investments by foreign players are expected to have a positive impact on industry growth over the next eight years.Growth Factors:Increasing demand of Sodium Aluminate from the construction industry for waterproofing and insulation products is expected to drive the growth of the sodium aluminate market over the forecast period.Rising demand for sodium aluminate in water treatment applications is also anticipated to fuel market growth over the next eight years. Growing use of sodium aluminate as a flocculant agent in various industries is projected to boost demand for this product during the forecast period.Increasing the application scope of sodium aluminate in pulp and paper processing is likely to propel market growth over the coming years.15SUBSTITUTE SHEET (RULE 26)Applications of Sodium Aluminate:Used as an effective source of Aluminum Hydroxide for many industrial and technical applications.In water treatment it is used as an adjunct to water softening systems also used as a coagulant aid to improve flocculation and for removing silica and phosphates.In Construction Technology, it is employed to accelerate the solidification of concrete mainly when working during frost.It is also used in paper IndustryIt is also used in fire brick productionIt is used for Alumina productionSodium Aluminate solutions are used as intermediaries in the production of zeolites.It is used in manufacture of milk glassIt is used in manufacturing of soaps and cleaning compounds.High purity Sodium Aluminate is used as raw material in semi-conductor industry.

[0006] BRIEF DESCRIPTION OF THE DRAWINGS:1. The fig. No. 1 on sheet No. 1 discloses a conventional Truck Mounted Concrete Transit Mixer which is Prior Art No.2.2. The fig No. 2 on sheet No. 2 discloses the present invention having a Hydrogen slave engine (3) & main Hydrogen Tank (4) & the emergency on-board generator.3. The fig No. 3 on sheet No. 3 discloses the detailed construction of the on-board Hydrogen Generator.16SUBSTITUTE SHEET (RULE 26)

[0007] DETAILED DISCRIPTION & WORKING OF THE INVENTION WITH REFERENCE TO THE DRAWINGS:Kindly refer to the Fig. No. 2 on sheet No. 2; which shows a vehicle mounted Mobile Concrete Equipment having one Mixer (1) for mixing & transporting concrete and a water tank (2) wherein the said mixer (1) is not operated by the Vehicle engine PTO but is operated by means of a dedicated slave engine (3);Wherein the said dedicated slave engine (3) is adapted to use Hydrogen gas as its primary fuel and is adapted to have a suitable capacity high pressure hydrogen gas storage cylinder (4) installed on the vehicle chassis.When the IC engine is adapted to use Hydrogen as Fuel, the following reaction takes place due to burning of Hydrogen inside the IC engine along-with intake air.Air / Fuel Ratio:The theoretical or stoichiometric combustion of Hydrogen and oxygen is given as-2 H2 + 02= 2 H20Moles of H2 for complete combustion: 2 molesMoles of 02 for complete combustion: 1 mole.Since, air is used instead of Oxygen, which is nothing but majority of Nitrogen.Moles of N2 in a ir= Moles of 02 X (79% of N2 in air / 21% of 02 in air)= 1 Mole of 02 X (79%of N2 in air / 21% of 02 in air)= 3.762 moles of N2Number of moles of air = Moles of 02+ Moles of N2 =1+3.762=4.762 moles.So weight of 02=1 mole of 02 X 32 g / Mole = 32 gram.17SUBSTITUTE SHEET (RULE 26)Weight of N2= 3.762 Moles of N2X 28 g / Mole = 105.33 gram.Weight of H2= 2 moles of H2 X 2 g of H2= 4 gram.Stoichiometric air / fuel ratio for Hydrogen & Air is :A / F based on mass = mass of air / mass of fuel= 137.33 +4 = 34.33:1A / F based on Volume= Moles of Air / Moles of Fuel= 4.762 / 2= 2.4:1Hence the percentage of the combustion chamber occupied by Hydrogen for a stoichiometric mixture= % of H2= moles of H2 / Total Volume= moles of H2 (moles of H2 +moles of air)= 2 / (4.762+2)=29.6%.Therefore, the stoichiometric or chemically correct A / F ratio for the complete combustion of Hydrogen in air is about 34:1 by mass. This means that for complete combustion, 34 kg of air is needed for each Kg of Hydrogen.In case when we use compressed Oxygen in place of air, all the NOX emissions shall be completely eliminated and the engine size also can be reduced considerably.However in practice, Hydrogen displaces almost 30% of the combustion chamber as shown above whereas Petrol displaces only 1 to % therefore the combustion chamber is redesigned in order to meet the requirement.Because of Hydrogen's wide range of flammability, hydrogen engines can run on air / fuel ratios of anywhere from 34:1 to 180:1.An Emergency on-board Hydrogen generator (5) is separately installed on the Truck Chassis having its own separate storage cylinder (6) which is adapted to produce Hydrogen in a safe and automatic way so as to18SUBSTITUTE SHEET (RULE 26)operate the concrete Mixer when the main storage cylinder (4) is exhausted;A selector switch is provided to change the fuel supply between the main fuel tank (5) and the on-board tank (6) adapted to be filled by the said emergency on-board Hydrogen Generator.Thus as shown the concrete mixer (1) is provided with a separate slave engine which is much smaller than the vehicle engine. This slave engine is adapted to use Hydrogen gas as fuel. The main storage tank or cylinder (4) is used to store Hydrogen gas at very high pressures. In normal operation when Hydrogen is available as refill, the slave engine (3) is adapted to operate on the Hydrogen fuel from the main tank. Alternatively the said slave engine is also adapted to operate on Hydrogen gas produced by an on-board Hydrogen generator (5) as shown in the Fig. No. 3 on sheet No. 3.Description & Working of the on -board Hydrogen Generator:Please refer to the Fig. No. 3 on Sheet No. 3 which shows an automatic on-board Hydrogen generator.The said on-board generator is made up of NaOH resistant steel. In practice SS 304 & 316 grade stainless steel is resistant to corrosion by NaOH upto a temperature of 80 deg. Since the disclosed hydrogen generator produces Hydrogen gradually and in small quantities only when it is needed it works below this range.As shown in the Fig, a custom designed solid material compartment (7) is adapted to have a small screw conveyor (8) at its bottom, adapted to operate by means of a small DC motor (9) operable by the vehicle battery; wherein the said solid material compartment (7) is installed on top of a liquid material compartment (10) in such a way that the said screw conveyor (8) is adapted to convey a pre-determined fixed flow of the solid material into the liquid material compartment (10) per each rotation of the screw (8).The said liquid compartment (10) is also adapted to operate as a reaction chamber as the reaction is adapted to start by virtue of the screw19SUBSTITUTE SHEET (RULE 26)conveyor (8) rotating & conveying the solid material into the liquid compartment (10).A DC compressor (11) is adapted to start along-with the said DC motor (9) and suck the gas produced in the liquid compartment (10) after the signal from pressure sensor (12) is received and is adapted to fill the another gas storage cylinder (6) wherein the said gas cylinder (6) is adapted to have another pressure sensor (13) pre-set with the maximum allowable pressure in the cylinder and is adapted to switch off the DC motor & the DC compressor once the preset pressure is reached so as to stop the gas production automatically.It is clear from the above description and the fig. no. 3 on sheet No. 3 that the screw (8) rotates only when the pressure in the tank (6) drops below a pre-set value along with the compressor and both are cut off once the gas pressure in the tank (6) reaches the maximum designed pre-set pressure.The said liquid compartment is provided means to add the liquid materials & remove the products after consumption of the solid material.The solid material used is Aluminum scrap & the liquid material used is aqueous NaOH solution. When the said screw (8) conveys the Aluminum to the liquid compartment (10), the hydrogen forming reaction takes place as follows:2 NaOH + 2AI +2 H2O= 2 NaAIO2 + 3 H2Thus 2 Moles of Sodium Hydroxide -NaOH (79.99 g) , 2 Moles of Aluminum Al (53.96g) and 2 Moles of water -H2O (36.03 g) react together to yield 2 Moles of Sodium Aluminate NaAIO2- (163.94 g) and 3 Moles of DiHydrogen H2- (6g).The molar mass of Sodium Hydroxide (NaOH) is 39.99 g; Molar Mass of Aluminum is 26.98 g and Molar mass of water (H2O) is 18.01 g. Molar mass of Sodium Aluminate Al is 81.97g and Molar Mass of Hydrogen- H2 is 2.01 g.20SUBSTITUTE SHEET (RULE 26)Therefore the emergency On-Board Hydrogen generator as disclosed above is made available in capacity sufficient to yield 1 Kg of hydrogen fuel (1000 g).The model which gives a yield of 1000 g of Hydrogen shall need around 8.92 kg of Aluminum Powder, 13.22 kg of NaOH and 5.95 liters of water and the containers are designed accordingly.Bigger capacity models such as 3Kg and 5kg yield can be easily manufactured when needed.The above weights are easily manageable as the Concrete Mixers are installed on 28 Ton GVW & above trucks and space is also not an issue. There are two main reasons why this is the ideal reaction to generate Hydrogen while many other solid & liquid materials can be used.

[0008] Techno-Commercial Significance:The use of hydrogen powered Internal Combustion Engines for Concrete Transportation as disclosed by the present invention shall completely eliminate the carbon foot print associated with the concrete transport activity.It will help in reducing the city air pollution and shall have a very positive effect on the environment and urban living.21SUBSTITUTE SHEET (RULE 26)

Claims

AMENDED CLAIMS received by the International Bureau on 16 May 2024 (16.05.2024)

1. [Amended]"Concrete Truck-Mixer Powered by Hydrogen slave engine" is characterized by: a. A vehicle mounted Mobile Concrete mixing Equipment having at least one Mixer (1) and a water tank (2) wherein the said mixer (1) is inoperative by the Vehicle engine PTO but is essentially operated only by means of a dedicated slave engine (3) at all times; b. Wherein the said dedicated slave engine (3) is adapted to use Hydrogen gas as its primary fuel and is adapted to have a suitable capacity high pressure hydrogen gas storage cylinder (4) installed on the vehicle chassis; c. An Emergency on-board Hydrogen generator (5) which is adapted to produce Hydrogen in a safe and automatic way by varying the flow of solid reactant using a screw conveyor (8) operated by a DC motor (9), so as to operate the concrete Mixer when the main storage cylinder (4) is exhausted.

2. [Cancelled]

3. [Cancelled)

4. [Cancelled]

5. [Cancelled]25AMENDED SHEET (ARTICLE 19)STATEMENT UNDER ARTICLE 19 (1)The amendments under Article 19 carried out as above do not have any effect on the drawings, abstract or any other part of the specification.The amendment of claim 1 is based on the following points.

1. Removal of negative expression: the words "not operated" have been replaced by synonym "Inoperative" so as to make if affirmative without changing the meaning of the same.

2. Please refer to para I - line 10 - of page no. 2 of the application body as filed- under the heading "[101]TECHNICAL FIELD" which is reproduced here as under-"This invention specifically relates to a Vehicle or Truck mounted Mobile Concrete Mixer which is not operated by the vehicle engine but by essentially is operated by means of an independent dedicated slave engine which is smaller in capacity than the Vehicle engine."Which clearly shows that the Mixer (1) is only operated by means of a independent dedicated slave engine at all times as the Mixer (1) is not operated by means of the Vehicle engine through PTO at any point of time. Kindly refer to the Claim 1 point a of the claim 1 as originally filed which also makes it clear that all prior arts where mixer (1) is operated by means of vehicle engine through PTO are not related arts.

3. Further refer to the Para II- line 15 of page no. 2 of the application body as filed which is also reproduced for immediate reference as under:"In particular this invention does not relate to the chemistry of hydrogen burning and hydrogen production method but specifically relates to the mechanical construction of the equipment and the apparatus." So there are many prior arts related to chemistry however the present invention is basically related to the mechanical construction of the equipment and the apparatus. Therefore it was essential to bring out the critical elements of the hydrogen generator of the present invention which are screw conveyor (8) and DC motor (9). Therefore this amendment was necessary to bring out the actual fact. Please refer to the “[005]SUMMARY AND DISCLOSURE OF THE INVENTION” - “point a” under the heading “An on board Hydrogen generator is characterized by-“. (on page no. 13-line 30, last para- of the application body as filed). From the same it is clear that the screw conveyor (8) and DC motor (9) are critical components which clearly brings out the Inventive step over related prior arts.Therefore the amendments are made in the interest of clarity as per article 6 of PCT and to incorporate actual facts in the claim 1.

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