JP2008514898A - Catalyst transfer system - Google Patents

Abstract

The present invention can be used directly in the flame zone of the combustion reaction system, directly in the feed air, feed fuel, or fuel / air mixture, or directly into the hot exhaust gas of the combustion reaction, or these three types. A catalyst aerosol delivery system is provided that generates an aerosol that includes a chemical catalyst precursor for delivery in any combination of the above.
The systems and compositions of the present invention can reduce pollutants released from the combustion chamber and can ensure more efficient and clean combustion. The combustion system and composition of the present invention can improve fuel economy in most applications.

Description

  The present invention can be used directly in the flame zone of the combustion reaction system, directly in the feed air, feed fuel, or fuel / air mixture, or directly into the hot exhaust gas of the combustion reaction, or these three A catalyst aerosol delivery system is provided that generates an aerosol comprising a chemical catalyst precursor for delivery in any combination of the above. The system and composition of the present invention can reduce pollutants released from the combustion chamber and can ensure more efficient and clean combustion. The combustion system and composition of the present invention can improve fuel economy in most applications.

  Delivery systems for generating sparging gases containing catalyst particles and supplying them into the flame zone of the combustion system are known in the art.

  Non-Patent Document 1 discusses existing technologies that can meet EU and US emission regulations for diesel trucks and other commercial vehicles, or heavy vehicles. These technologies include diesel oxidation catalyst, DeNOx catalyst and nitrogen oxide (NOx) absorber, selective catalytic reduction (SCR) and diesel particulate removal device (DPF), and particulate matter crankcase emission control filter technology including.

  Catalytic converters were first introduced to passenger cars in the United States in 1974 and are now installed in over 275 million of the 500 million cars worldwide, accounting for nearly 90% of all new cars produced worldwide Is provided with a catalytic converter. However, the exhaust emission control technology for diesel-powered high horsepower engines is not so widespread.

  Another issue of concern is the sulfur content of diesel fuel. Since sulfur is strongly adsorbed on the catalyst surface, it has a significant negative effect on the catalyst performance. Thus, the surface area of the catalyst is reduced, resulting in a reduction in the amount of nitrogen dioxide formed on the oxidation catalyst. This creates a problem because some DPF and NOx absorbers rely on nitrogen dioxide to perform regeneration. Further, sulfur reacts more strongly with chemical NOx traps than NOx, thus reducing NOx storage capacity and requiring stronger and more frequent regeneration, thus increasing fuel consumption.

  Note that diesel oxidation catalysts convert carbon monoxide and hydrocarbons to carbon dioxide and water. Thus, these systems have been found to reduce the amount of particulate matter emissions but have little effect on NOx emissions.

  Diesel oxidation catalysts can also be used with NOx absorbers, DeNOx catalysts, DPF or SCR to reduce nitrogen dioxide levels or to purify injected hydrocarbon, urea or ammonia bypass.

Conventional automotive catalytic converters consist essentially of a ceramic honeycomb through which exhaust gases pass. The inside of the catalytic converter is coated with a fine particle layer of platinum or palladium, rhodium, and cerium catalyst. Platinum component of the catalyst to oxidize CO to CO _2, to oxidize the UHC to CO ₂ and steam, rhodium, reducing the level of NOx formed.

  Catalytic converters degrade over time and with use. Since 1984, catalytic converters have been installed in all German vehicles. As a result, trace amounts of platinum and rhodium are detected on the autobahn.

  Patent Document 1 discloses a sparging gas catalyst transport system in which a catalyst mixing receiver includes an inlet pipe, a secondary splash chamber, and an air inlet connected to a gas outlet. The gas is sparged into the liquid in the receiver through a tube with an outlet near the bottom of the liquid, and the resulting combination of gas, vapor from the liquid, liquid splash, and catalyst enters the combustion zone. Directed. However, according to the specification of Patent Document 1, it is important to note that the liquid vapor and the liquid catalyst splash are not carried to the combustion zone, and a secondary splash chamber is required in the literature. This chamber reduces the performance of the system and is therefore used to reduce the effectiveness of the liquid catalyst that splashes or condenses in the communication tube between the receiver and the combustion zone. Further, Patent Document 1 points out that such a splash is not desirable because it results in uncontrolled consumption of the catalyst mixture. This makes combustion unpredictable and / or the catalyst consumption rate too high.

  Further, Patent Document 2 includes a sparging pipe connected to a gas inlet, from which a gas, usually air, is passed while being bubbled into the catalyst mixture through a pipe having an outlet near the bottom of the liquid. A transport system is also disclosed. In this method, the catalyst particles can be fluidized without being evaporated and carried into the oxidation flame zone by bubbles being repelled at the liquid-gas interface by the gas flow. The catalyst particles are then carried into the flame zone by a gas stream through a transport line.

  A problem with using a sparging gas to introduce a catalyst or catalyst precursor into a combustion system is that some of the catalyst or catalyst precursor can adhere to the surface in contact with the gas stream. . Thus, some of the catalyst precursor used in the prior art adheres to the surface of any supply line through which sparging gas exiting the catalyst solution receiver flows before reaching the combustion chamber. This reduces the efficiency of the system and wastes expensive catalyst material.

  An aerosol is defined as a fine dispersion in which solid or liquid particles are dispersed in a gas. The aerosol delivery system used in the present invention functions in a manner similar to that used when spraying a dilute solution into a flame as used in atomic absorption spectroscopy. The process of generating an aerosol as a fine particle spray can be referred to as spraying or atomization. Aerosols are generated by sucking or pumping liquids, mixing with gas, usually air, under turbulent flow, and exhausting through one or more small orifices. The amount of air used depends on various parameters, including gas flow and liquid flow. Aerosols can also be generated by releasing only liquid under high pressure through one or more small orifices. Ultrasonic devices can also be used to generate finely dispersed aerosols. In the context of the present invention, the terms atomization and atomization can be used interchangeably to indicate the supply of aerosol, which aerosol is in the pre-combustion zone and / or in the combustion zone and / or after-combustion. It consists of a fine spray of catalytic material sent to the strip. Aerosol delivery systems are known in the art. To date, however, this type of system has not been used to deliver catalytic material to the combustion zone.

  The generation of aerosols according to the present invention should be distinguished from the principle of sparging, which involves the process of passing a chemically inert gas through the liquid to produce bubbles. In the case of the present invention, the aerosol is formed by turbulent mixing of a liquid containing a catalyst in a solution and a gas under pressure immediately before being discharged through a fine nozzle. Mixing and spraying in this manner provides a steady state and continuous supply of aerosol containing catalyst at trace levels.

International Publication No. 02/082831 Pamphlet US Pat. No. 6,776,606 Business Briefing: "Global Truck and Commercial Vehicle Technology"; London 'World Marketing Research Centre; 2000; p.97-102; EU Directive 1999/99 EC

  The object of the present invention is to eliminate or improve various drawbacks of the characteristics of systems according to the prior art. Accordingly, it is an object of the present invention to provide an aerosol delivery system that can be introduced into one or more of the intake or combustion zones, or directly into the hot exhaust gas of the combustion system.

  It is another object of the present invention to provide an aerosol delivery system that significantly improves the reduction of CO, NOx, UHC, and sulfur oxide emissions from the combustion system as compared to prior art systems.

  Another object of the present invention is to provide an aerosol delivery system that reduces the corrosion that occurs in combustion systems that employ low NOx burners, thereby extending the life of such combustion systems compared to prior art systems. That is.

  Another object of the present invention is to provide an aerosol delivery system that enhances the combustion efficiency of the combustion system as compared to prior art systems. Accordingly, it is an object of the present invention to maintain the flame temperature of the combustion system and reduce excess air levels to improve the thermal efficiency of the combustion system.

  It is also desirable for the aerosol delivery system of the present invention to reduce the amount of carbon and char deposited inside the combustion system.

  Furthermore, it is also desirable for the aerosol delivery system of the present invention to reduce noise and vibration associated with combustion systems as compared to prior art systems.

  Another object of the present invention is to provide an aerosol delivery system that can be used to revive inefficient converters, such as converters that have been operating for a period of time.

  Another object of the present invention is to provide an aerosol delivery system in which the catalyst is retained within the combustion system.

  Another object of the present invention is an aerosol that interacts with mercury present in coal and other combustible materials and hot gas streams to prevent or reduce the amount discharged into the exhaust gas. It is to provide a transport system.

  Applicant has surprisingly solved these and other problems by sending the catalyst or catalyst precursor directly into and around the combustion site by using an aerosol delivery system. I found out that I can do it. Therefore, the present invention achieves some or all of the above objects.

According to one aspect of the invention, an aerosol delivery system for use with a combustion device is provided, the system comprising:
A first inlet for supplying a source of gas to the chamber;
A second inlet for supplying a catalyst solution comprising one or more inorganic metal salts in a solvent to the chamber;
Comprising a chamber with an atomizing nozzle for discharging fluid in the form of an aerosol from the chamber;
The first and second inlets and the atomization nozzle are arranged so that the gas and fluid in the chamber are mixed and combined to form an aerosol when released through the nozzle, the nozzle being pre- In fluid communication with one or more of the combustion zone, the combustion zone, and the post-combustion zone.

  In one embodiment, the nozzle is in the combustion zone. In other embodiments, the nozzle is in a pre-combustion region where air and fuel are mixed prior to combustion. In other embodiments, the nozzle can be placed in a pre-combustion region with only fuel and / or the nozzle can be placed in a pre-combustion region with only air, ie the two components are mixed. Can be put before. In other embodiments, the nozzle can be placed in the post-combustion region. Thus, the nozzle supplies aerosol to the combustion products in the exhaust region. The nozzle comprises one or more nozzles that can discharge the fluid mixture in the form of an aerosol. The shape of the aerosol emissions exiting the nozzle depends on the size, number and arrangement of nozzle nozzles. Therefore, the aerosol shape can be made as needed. A substantially conical shape is preferred for the nozzle because a conical aerosol is obtained.

  In other embodiments, there can be multiple nozzles. As such, the nozzle can independently supply aerosol to one or more of the above regions. The catalyst solution may be the same or different in each case. The nozzle shape and nozzle array may be the same or different in each case where there are a plurality of nozzles.

  In one embodiment of the invention, the supply of gas and catalyst solution to the chamber is continuous and the aerosol can be continuously sprayed from the nozzle. Alternatively, the supply of gas or solution to the chamber can be interrupted so that the aerosol is sprayed intermittently from the nozzle.

  Aerosols can also be generated without the use of air. When the catalyst precursor solution is exposed to high pressure and discharged from a very fine nozzle, it emerges as an aerosol. Thus, in other embodiments of the above application, such a generation system is gas-free high pressure when the aerosol is described as being generated using a gas, such as air, in combination with a solution of the catalyst. It can be replaced by a system and does not require a supply of compressed gas. It is sufficient to simply supply a solution of the catalyst under pressure to the nozzle. This embodiment has application in all cases where aerosols are produced by mixing gas and solution, such as industrial burners, boilers and SI and diesel engines (ie open flame and Both systems of closed flame).

  Combustion can take place in direct flame or closed flame applications. Direct flame applications include boilers and furnaces powered by coal, gas, and petroleum. Closed flame applications include gasoline and diesel internal combustion engines. In one embodiment of the invention, the aerosol is used in a vehicle equipped with a catalytic converter.

  As used herein, a combustion zone refers to and includes a region where fuel oxidation occurs and a region directly surrounding that region, such as a combustion chamber.

  The one or more metal salts in the catalyst solution are catalysts for the combustion of the consumed fuel or the oxidation or reduction of the combustion products (exhaust) to harmless or clean products. The catalyst can be a simple compound, a binary compound, a complex metal salt, or an organometallic compound.

  Preferably, the catalyst solution of the present invention comprises platinum, palladium, rhodium, rhenium, ruthenium, osmium, cerium, iridium, indium, magnesium, aluminum, titanium, copper, zinc, lithium, potassium, sodium, iron, molybdenum, manganese, Contains one or more inorganic salts or organometallic compounds of gold or silver. Preferably, the solution of the present invention comprises one or more compounds of Group VIII elements (ie Fe, Ru, Os, Co, Rh, Ir, Ni, Pd, Pt), magnesium, or aluminum. Preferably, the compound is a platinum, rhodium, rhenium, magnesium, or aluminum compound. If only one compound is used, the solution must contain a platinum or rhodium salt.

  In one embodiment, the compound is present in the solution at a concentration from 0.1 to 2.0 mg / ml. More preferably, this concentration ranges from 0.2 to 1.0 mg / ml. The molar weight of the compound can be from 200 to 2000, more preferably in the range from 200 to 750.

Inorganic metal salts exist as H ₂ PtCl ₆ , RhCl ₃ , HReO ₄ , MgCl ₂ , and AlCl ₃ . Complex ions formed in water from such inorganic metal salts include [PtCl ₆ ] ²⁻ , [Rh (H ₂ O) ₆ ] ³⁺ , and [ReO ₄ ] ⁻ .

In a preferred embodiment of the present invention, the catalyst precursor solution concentrate comprises one or more metal salts wherein the metal is selected from platinum, rhodium, rhenium, or aluminum. In the catalyst precursor solution concentrate, H ₂ PtCl ₆ . The concentration of platinum present as 6H ₂ O is in the range of 0.2 to 1.0 mg / ml, more preferably in the range of 0.5 to 0.7 mg / ml, particularly preferably 0. A concentration of 6 mg / ml. The concentration of rhodium present as RhCl _{3 in the} catalyst precursor solution concentrate is preferably in the range of 0.04 to 1.2 mg / ml, more preferably 0.06 to 0.09 mg / ml. Within the range, the concentration is particularly preferably 0.07 mg / ml. The concentration of rhenium present as HReO _{4 in the} catalyst precursor solution concentrate is preferably in the range of 0.05 to 1.5 mg / ml, more preferably 0.08 to 1.2 mg / ml. Within the range, the concentration is particularly preferably 1.0 mg / ml. The concentration of aluminum present as AlCl _{3 in the} catalyst precursor solution concentrate is preferably in the range of 0.05 to 1.0 mg / ml, more preferably 0.07 mg / ml.

In another preferred embodiment of the present invention, the aluminum in the solution of the present invention has a concentration in the range of 0.05 to 1.0 mg / ml, more preferably MgCl _{2 at} a concentration of 0.07 mg / ml, etc. Replaced by magnesium.

  In yet another preferred embodiment of the present invention, only a portion of the aluminum is replaced with magnesium so that the catalyst precursor solution contains both aluminum and magnesium.

  In yet another preferred embodiment of the invention, when both platinum and rhodium are present in the catalyst solution, the ratio of platinum to rhodium is about 8.6: 1 and the ratio of platinum to aluminum is Is about 8.6: 1, the ratio of platinum to rhenium is about 6: 1, and when aluminum is replaced by magnesium, the ratio of platinum to magnesium is about 8.6: 1. is there.

  However, the ratio of the components of the present invention may be higher or lower than these ranges. Accordingly, the ratio of platinum to rhenium is preferably in the range of 30: 1 to 1: 1, more preferably in the range of 15: 1 to 2: 1. The ratio of platinum to aluminum or magnesium is preferably in the range of 30: 1 to 1: 1, more preferably in the range of 15: 1 to 2: 1. The ratio of platinum to rhodium is preferably in the range of 30: 1 to 4: 1, more preferably in the range of 15: 1 to 4: 1.

  In another preferred embodiment of the present invention, the catalyst precursor solution comprises platinum alone and one other inorganic metal salt of rhodium, rhenium, magnesium, or aluminum.

  The solvent can be one that can dissolve one or more metal salts (catalysts) and can form a stable aerosol. Ideally, the solvent has a significant vapor pressure at normal temperature and pressure, but the solvent should not be too volatile, otherwise the catalyst will be deposited early in the feed line. And / or may be consumed quickly. The most effective solvents are those with boiling points in the range of 80 ° C to 140 ° C at normal temperature and pressure. The solvent is preferably water. Alcohols (such as methanol or ethanol) or hydrocarbon solvents can also be used as solvents. The solvent may further be a suitable solvent mixture. Water is a preferred solvent because it has the ability to dissolve many inorganic metal salts and to form stable aerosols.

  The solvent can further include an antifreeze such as, for example, ethylene glycol. Other additives can be included as needed.

In another aspect, the present invention provides a method for catalytically combusting fuel, the method comprising:
a) providing a catalyst solution and a compressed gas to the chamber, the chamber comprising a nozzle in fluid communication with one or more of the pre-combustion zone, the combustion zone, and the post-combustion zone;
b) mixing the solution and gas in the chamber;
c) forcing the mixture of solution and gas through the nozzle and forming an aerosol in the pre-combustion zone, combustion zone, or post-combustion zone of the fuel combustion device.

  The aerosol and fuel of the present invention can be introduced simultaneously or separately into the combustion zone of a fuel-injected diesel or gasoline engine.

  In one embodiment of the invention, the aerosol can be introduced into the combustion zone of the engine along with air from the carburetor. In order to minimize the distance between the point where the inorganic metal salt is introduced into the combustion system and the required point of use (ie, the combustion zone), the aerosol is placed in the spark ignition engine's air stream just prior to entering the carburetor. Introduced and mixed with volatile fuel, the mixture enters the engine. In the case of a diesel engine, the aerosol is introduced into the air stream after passing through the air filter.

  Combustion requires the presence of radicals in and around the flame, and catalytic materials such as platinum and / or rhodium introduced by the system of the present invention into the combustion process significantly improve the process. This is accomplished by increasing the amount of radicals generated, thereby reducing the amount of excess oxygen normally required and thus saving fuel. This also improves emissions.

  In one embodiment, the invention introduces combustion system harmful emissions, particularly NOx, by introducing an aerosol comprising one or more inorganic metal salts into the final hot exhaust gas stream of the combustion system exiting the combustion system. Provide a way to reduce. These systems may or may not employ emission reduction systems within the combustion zone, before the combustion zone, or immediately after the combustion zone. Preferably, the aerosol of the present invention is introduced into the hot exhaust gas stream of an internal combustion engine (using diesel, gasoline, biodiesel, and alternative fuels, etc.), or power plant or process station boilers, burners, and dryers. The

  Coal is one fuel that can benefit from the combustion technology of the present invention. One of the major applications of the present invention is therefore the application of various NOx reduction technologies used in coal combustion. In particular, this process can be applied to coal combustion in furnaces and boilers that employ various NOx reduction devices and procedures to reduce carbon in ash and the like.

  The two main mechanisms of NOx formation in the combustion process are thermal NOx and fuel NOx. The former is dominant when the fuel does not inherently contain nitrogen (eg, natural gas), and the latter is dominant when the fuel is coal or heavy oil. Combustion improvement techniques aim to limit NOx formation in the early stages of the combustion process. The process of the present invention is compatible with and applicable to these methods.

  Preferably, the aerosol of the invention is added to the hot exhaust gas stream of the combustion system, either directly or indirectly, with ammonia or urea, and optionally added to obtain the required reaction temperature. Introduced with hydrogen and air. The aerosol of the present invention can be used in a hot exhaust gas stream of a combustion system that employs an ammonia / urea / hydrocarbon / air system for NOx, CO, and carbon reduction, or other suitable site, particularly SNCR (selection Can be introduced simultaneously or separately into coal power and similar oil or solid fuel power plants that employ a non-contact reduction strategy.

  In the air staging method for reducing NOx, combustion air is divided into a plurality of stages, the primary combustion zone operates at the total fuel excess theoretical air-fuel ratio, and the remaining air is injected downstream. In order to apply the process of the invention to this method, it is necessary to inject the catalyst at the appropriate point in both stages. Low NOx burners are designed to provide a staging effect by splitting the air flow and fuel flow inside the burner in such a way as to retard combustion, reduce oxygen utilization, and lower the peak flame temperature. All of these factors help reduce NOx. In order to apply the process of the present invention to this method, in addition, it enhances the radical reaction which reduces the NOx still formed, thereby improving its efficiency and the overall efficiency of NOx reduction, as well as the overall combustion process. It involves introducing an aerosol catalyst at all points so that the efficiency can be improved.

  NOx levels can also be reduced by flue gas circulation techniques that introduce diluent into the combustion chamber. Applying the process of the present invention to this method involves introducing an aerosol catalyst and mixing well with the diluent. Another way to reduce NOx is by reducing excess air levels. This reduces NOx but creates undesirable problems such as unstable combustion, reduced burnout, slagging, fouling, and corrosion. However, when the aerosol catalyst of the present invention is used, the fuel process can proceed normally, and these problems can be minimized. This is due to excess radicals generated in the flame.

  There are also many post-combustion NOx control technologies. These are generally referred to as exhaust gas treatments and can be classified as (a) selective catalytic reduction (SCR), (b) selective non-catalytic reduction (SNCR), and (c) non-selective catalytic reduction (NSCR).

  The method (b) uses injection of ammonia gas, ammonia water, or urea water into the combustion exhaust gas. The radical reaction that occurs essentially converts NOx to oxygen and nitrogen, but this reaction only occurs under limited reaction conditions. When an aerosol catalyst according to another aspect of the present invention is introduced into the flue gas (in the same way that the aerosol catalyst is introduced into the combustion zone or pre-combustion zone), these reactions are enhanced and the operating temperature range is expanded. According to the process of the present invention, the catalyst is injected into ammonia gas or ammonia water or urea water, or together with ammonia gas or ammonia water or urea water, and / or other salts are added to the flue gas as needed. .

  The catalysts supplied to the flue gas by the method of the present invention can also be used to maintain the efficiency of the SCR catalyst and extend the life of the SCR catalyst, provided that they are platinum based or otherwise This is the case where the catalyst material is recognized. The platinum and rhodium homogeneous catalyst in the gas stream entering the catalyst grid system helps the catalysis to occur on the catalyst and adheres to the platinum base or some other catalyst, and the platinum and rhodium staying there is carbon dioxide. Joining the oxidation to gas by employing a catalyst helps to prevent carbon and char deposition on the SCR catalyst.

  One example relates to a combustor that uses SCR, SNCR, or NSCR technology to reduce NOx. Some NOx remains intact and can leave the plant and enter the atmosphere through the final stack, and is common. The technique used to reduce the final stack NOx uses a final stack injection of ammonia or urea. If the temperature is not high enough, an open flame that burns a suitable hydrocarbon gas is also used to bring the outlet gas into the temperature range, thereby reacting ammonia or urea with NOx. The atomized catalyst can be injected into the spark prior to entering the radical reaction zone. This forms platinum and rhodium catalyst species, reduces the temperature range, makes the radical reaction more efficient, reduces the amount of gas needed for the ignition, and leads to fuel savings.

  The process of the present invention has many applications. The generated aerosol or spray is injected into an air stream that mixes with the fuel and enters the combustion zone. This concept can be extended to all high temperature reactions involving chemical and radical mechanisms. As such, the present invention further includes the concept of introducing an aerosol catalyst into all situations where a gas phase radical reaction is known or assumed to occur and the application of the process involves combustion. It can also include high temperature chemical reactions involving radicals, especially those involving homogeneous and heterogeneous catalysts in the petroleum refining industry. The oil refining industry and some related industries use platinum catalysts at high temperatures. This must be cleaned or replaced as it degrades over time and as usage progresses. The present invention has the potential to extend the life of such catalysts and increase efficiency.

  The technology of the present invention as described herein is further applied in the petroleum refining industry because the catalytic combustion process of the present invention enhances performance and production, and further reduces maintenance. One particular problem in this area is undesirable soot deposits in furnaces that supply thermal energy to, for example, petroleum distillation plants, and soot must be removed periodically. The present invention also provides a method for solving such problems.

  The process of the present invention can also be used for soot and char combustion along with CO purification. All of these processes can be enhanced by catalytic aerosol injection since radical reactions are involved in each of these processes. Applications include catalytic crackers, reformers and other refining processes, and fluidized bed combustion processes.

  In other embodiments of the present invention, aerosol sprays are used to perform sulfur capture using one or more additives based on compounds of Group II elements of the Periodic Table. There are a variety of chemicals and procedures used to remove sulfur oxides from exhaust and flue gas. Simultaneous injection of precious metal catalyst and these chemicals, or if the gas temperature is too low to produce elemental metal, will improve the sulfur removal efficiency and expand the low temperature limit of the reaction involved. It is considered.

  This process can also capture traces of mercury in a similar manner. Currently, techniques for removing mercury from coal during combustion are desirable, but have not been or have not been fully demonstrated. Mercury easily forms amalgam with most metals (except iron) except when it contains precious metals, and adheres to the platinum and rhodium coating surfaces formed under conditions associated with them in coal-fired boilers. It is considered. None of the mercury removal technologies currently being tested uses the properties of mercury to form amalgam.

  In one embodiment, the metal (catalyst) derived from the solution used in the present invention is either retained in the combustion chamber, attached to the surface through which the exhaust gas passes, or in the honeycomb structure of the catalytic converter. Be trapped. This is advantageous because the deposited metal (catalyst) is further involved in heterogeneous catalysis, thus providing a continuously regenerated catalyst surface where a continuous reaction occurs.

In another aspect of the invention, a method for pretreating fuel is provided, the method comprising:
a) providing a catalyst solution and a compressed gas to the chamber, the chamber comprising a nozzle in fluid communication with one or more of the pre-combustion zone, the combustion zone, and the post-combustion zone;
b) mixing the solution and gas in the chamber, forcing the mixture of solution and gas through a nozzle to form an aerosol, and adding the aerosol to the solid fuel to pre-treat the fuel prior to combustion Including.

  The fuel is preferably a solid fuel.

  Some embodiments of the invention include boilers, power plant or process station boilers, burners and dryers, furnaces, turbine engines, reciprocating engines, incinerator engines, direct flames, spark ignition engines, natural gas engines, gasoline engines Aerosol catalyst compositions in either direct flame or closed flame applications, such as rotary engines, diesel, gasoline, biodiesel, or internal combustion engines using gasoline engines and other alternative fuels, or systems in which the fuel is oxidized It may include using a transport system. Usually, fuel oxidation involves combustion in air or oxygen-rich media. Oxidation can be influenced by providing other oxygen generating sources that liberate oxygen under combustion conditions.

  The aerosol delivery system of the present invention includes a rigid container that is not affected by the solution contained therein. The container can be made from a material that is suitable for the desired use of the aerosol. In one preferred embodiment of the invention, the aerosol container is made from ceramic, metal, or plastic, or a combination thereof.

  The compressed gas of the aerosol delivery system is an aerosol such as a positively or negatively ionized or neutral gas selected from, for example, air, steam, nitrogen, argon, helium, carbon monoxide, carbon dioxide, and combinations thereof The gas can be suitable for the desired use. Preferably, the compressed gas is air. Under certain circumstances, the compressed gas includes air and an additional oxygen component or ammonia gas.

  Preferably, the aerosol delivery system gas is exposed to a pressure in the range of 30 to 90 psi. More preferably, a pressure in the range of about 50 to 70 psi is required.

  The solution in the aerosol delivery system is exposed to pressure. Preferably, the solution is exposed to a pressure in the range of about 20 to 70 psi. More preferably, the solution is exposed to a pressure in the range of about 30 to 50 psi.

  There are various ways to generate aerosols. A system that generates an aerosol can in principle be used to generate a catalyst aerosol, the choice depending on the intended application of the catalyst aerosol.

  The pH of the catalyst precursor solution used in the aerosol delivery system of the present invention must be such that it prevents degradation or degradation that occurs with subsequent formation of colloids or fine precipitates, and is preferably less than 5. More preferably, the pH of the catalyst precursor solution is in the range of 4 to 1, even more preferably in the range of 3.0 to 1.4, particularly preferably 1.6 to 2.2. Within the range.

  In a preferred embodiment, the present invention generates a plurality of catalysts in a flame or exhaust gas and introduces the precursors directly or using inlet air into the flame or exhaust gas. ing. This increases the oxygen atom concentration and free radical generation and improves the combustion rate, thereby improving the efficiency in residence time.

  Some of the inorganic metal salts and organometallic compounds decompose into elemental forms in hot flames or in hot exhaust gases and form as intermediates during conventional combustion elements and combustion processes that catalyze reaction with oxygen It is believed to produce molecules and radicals. In the present invention, platinum, palladium, rhodium, rhenium, ruthenium, osmium, cerium, iridium, indium, magnesium, aluminum, titanium, copper, zinc, lithium, potassium, sodium, iron, molybdenum, manganese, gold, or silver At least one elemental form is present in the flame or in the hot exhaust gas at a level in the region of ppm to ppb. Preferably, platinum and rhodium are present at a level in the range of ppm to ppb in the flame or in the hot exhaust gas. The concentration of inorganic metal salt or organometallic compound in the aerosol introduced into the combustion system or into the hot exhaust gas depends on the size and characteristics of the respective combustion system.

  The aerosol delivery system of the present invention comprises an amount of an inorganic metal salt or organometallic compound in a level from ppm to ppb depending on the heat output and size of the combustion system. Preferably, the one or more inorganic metal salts are present in the solution at a concentration in the range of 1 to 1000 ppb. More preferably, the one or more inorganic metal salts are present in the solution at a concentration in the range of 50 to 100 ppb. It has been found that very low levels of inorganic metal salts are necessary to act as a catalyst. This allows these catalyst precursors at levels from ppb to ppm to be carried into combustion chambers such as coal or gas powered industrial boilers or spark ignition and combustion chambers of diesel engines. Thus, the aerosol of the present invention effectively places an inorganic metal salt or organometallic compound in the region where combustion takes place.

  The dosage of the diluted catalyst precursor solution in the form of an aerosol of the present invention depends on the desired use. However, the dosage is preferably in the range of 0.1 to 1 US gallon (0.3785 liters to 3.785 liters) per hour. More preferably, the dosage is 0.5 US gallons (1.8925 liters) per hour. The degree of dilution depends on the rate at which fuel is consumed or heat energy is supplied by the boiler.

  In other embodiments of the invention, the aerosol is diesel fuel, gasoline, number 2 fuel oil, bunker oil, fuel oil refined from crude oil, compressed natural gas, liquefied natural gas, gasohol, hydrocarbons, corn oil, vegetable oil Used for combustion chambers using fuels such as mineral oil, coal, coal gas, asphalt steam, oxidizable steam, wood, paper, straw, biofuel, combustible waste, and combinations thereof.

  The operating temperature of the combustion system suitable for use with the aerosols of the present invention is preferably in the range of 500 to 2000 ° C, preferably in the range of 900 to 1600 ° C, more preferably 1000 to 1500. Within the range up to ° C.

  Referring to yet another aspect, the present invention provides a small aerosol delivery system for use with a diesel or gasoline engine. The size of the aerosol delivery system depends on the intended use of the aerosol. The system can be configured, for example, to avoid the high temperatures associated with coal fuel plants, so a small system that employs an ultrasonic generator (see above) can be used to generate a fine aerosol. .

  Preferably, the width of the small aerosol delivery system of the present invention can be between 10 cm and 2 m depending on the intended use.

  Another advantage of the present invention is that the engine vibration to which the aerosol delivery device and method of the present invention is applied allows for complete mixing of the catalyst precursor solution.

  Another advantage of the present invention is that the elemental forms of catalyst salts or organometallic compounds, such as platinum and rhodium, adhere to the interior of the furnace and other interiors derived from the components of the catalyst aerosol. Adhering to the compound, the catalytic activity therefore persists beyond the time period during which the catalyst mixture is sprayed into the system.

  Aerosol delivery systems can advantageously reduce the noise and vibration associated with combustion engines. For example, the presence of platinum is believed to cause the flame to burn at low temperatures in a diesel engine and therefore does not disappear before the piston reaches the end of its stroke. A characteristic of a diesel engine is “rattle noise”, often referred to as harmonics. This occurs when the energy of the expanding gas decreases beyond a certain point due to a temperature drop due in part to adiabatic expansion and when the flame is extinguished. When this happens, the piston will continue to travel approximately 1/4 of the stroke. The movement of the piston at this point changes from a pushing operation to a pulling operation, and generates a rattling sound. When the aerosol delivery system of the present invention is installed, the harmonics are significantly reduced and the engine is much quieter and smoother. Under normal circumstances, when combustion begins, the resulting expansion causes the cylinder to be pushed down. The platinum-containing aerosol system of the present invention is responsible for generating oxygen atoms, so that the flame and expansion will last long. Furthermore, platinum is believed to contribute to high speed combustion, thereby sustaining the flame and increasing the power level generated.

  The optimum conditions for operating a spark ignition engine with minimal CO and NOx emissions are somewhat in conflict. The higher the temperature in the combustion chamber, the less CO will be formed, thus minimizing CO emissions by operating the engine as hot as possible. However, the opposite is true for NOx formation, in order to minimize emissions, the temperature in the combustion chamber must be as low as possible. Currently, the engine is tuned for catalytic converter efficiency to be close to the intersection of plots of CO and NOx formation as a function of temperature.

  An inherent advantage of the aerosol delivery system of the present invention is that the combustion temperature is in the range centered on the intersection temperature to minimize CO, NOx, and unburned hydrocarbon levels in the exhaust gas from the combustion chamber. It is mentioned that it is not necessary to design to fit. Thus, in the low temperature regime, the amount of NOx formed is small and this amount is further reduced by the presence of rhodium in the combustion chamber. Another result and advantage is that the work load on the catalytic converter is now significantly reduced, thus increasing its efficiency and lifetime.

  Inclusion of rhenium in the catalyst concentrate of the present invention is believed to contribute to smooth and quiet operation of the engine, and therefore its role is to facilitate smooth flame combustion and smooth against flame. It is considered to be the forefront.

  Applicants have surprisingly discovered that the aerosol delivery system of the present invention improves the combustion characteristics of the fuel and thus reduces the carbon deposited in the combustion system. Furthermore, the amount of catalyst can be reduced later or thereafter. In some situations, the aerosol delivery system of the present invention produces a bright blue flame, which indicates particularly efficient fuel combustion. The advantage of this technique is that the combustion system has a clean interior, a clean fly ash, and a small but steady injection of catalyst and no catalytic corrosion or poisoning. Thus, the present invention can extend the life of the combustion system.

  The present invention is illustrated by several figures.

  In FIG. 1, the supply of air 1 is sent to a blower 2 and further to a mixing device 3 where it is combined with fuel from a fuel source 4. Oxygen can also be used to supplement the air or instead of air. The air / fuel mixture 5 is fed to a combustion chamber 6 where combustion takes place. The combustion product 7, ie the exhaust gas, then leaves the combustion chamber and passes through an exhaust region 8 with a heat exchanger 9.

  Reference characters a to i indicate injection sites suitable for the arrangement of the aerosol delivery system of the present invention. Therefore, the aerosol spray containing the catalyst solution can be supplied to any of the parts indicated by letters a to i. A plurality of such sites can be present in the device. When multiple sites are present, the catalyst solution supplied may be the same as or different from other aerosol supply sites in the same application. Preferred sites are one or more of a, c, and d because it improves combustion and reduces fuel consumption. In order to lower the NOx level, an aerosol supply site in the post-combustion zone is preferred. Therefore, supply by g, h, or i is preferable. The injection can also be performed with or without the addition of ammonia or urea (not shown in the figure) to these areas.

  FIG. 2 shows a simple injection device for supplying the catalyst solution into the vortex chamber 11 in the aerosol supply head 12 with a tangential inlet tube 10. The compressed gas is supplied to the vortex chamber 11 through the pipe 13. The atomizing nozzle 14 includes orifices 15 that are sized and arranged to provide a fine aerosol mist 16. In the embodiment shown in the figure, the atomizing nozzle 14 is generally conical and a conical aerosol mist 16 is obtained. The gas and catalyst solution are mixed well in the vortex chamber 11 prior to discharge through the orifice 15 in the nozzle 14 for positioning of the gas tube 13 and tube 10 in the vortex chamber 11.

  FIG. 3 shows a simplified top view of the aerosol delivery device of FIG. It can be seen that the nozzle holes 15 are arranged so as to draw a regular pattern around the atomizing nozzle 14. The orifice pattern depends on the shape of the desired atomized spray. FIG. 3 shows a conical atomization nozzle 14 which results in a conical spray of aerosol 15 with the most advantageous effects in terms of reducing fuel consumption and improving NOx levels.

  FIG. 4 shows a water-cooled atomizer 17 which passes through the furnace wall 18 and through the inner insulating ceramic brick tension 19 of the furnace. The atomizer 17 is made of metal and includes a water jacket 20 formed by providing a supply source of the cooling water 21 that passes through the flow path 22 in the main body of the atomizer 17. The catalyst solution 23 is supplied to the vortex chamber 25 through the flow path 24. The compressed gas 26, in this case air, is supplied to the vortex chamber 25 by the flow path 27. The catalyst solution and air mix in the vortex chamber 25 and pass through the atomization nozzle 28 to form an aerosol 29 spray cone.

  The following examples demonstrate the effectiveness of the present invention.

  Boilers (Johnston 800 hp rated 33 million BTU per hour) were less efficient at generating steam and the amount of gas supplied was increased to offset this. The boiler was inspected and found that combustion was incomplete and carbon was deposited in the furnace due to a faulty air supply. This boiler air delivery system was repaired and fitted with the aerosol delivery system of the present invention. Subsequent measurements showed that the noise level decreased from 107 dB to 97 dB after the aerosol of the present invention was installed. The boiler was operated for one month near the maximum load and operated with the aerosol delivery system of the present invention. After one month, the interior of the furnace was quite clean and the fuel savings were found to be about 4%. Further measurements showed that NOx levels decreased from 26.8%, 149 ppm to 109 ppm after 6.5 weeks. After operating with an aerosol delivery system for 13 weeks, the NOx level was reduced by 33% overall to 100 ppm and the overall fuel savings was found to be about 4%.

  Another boiler (Johnston 800 hp rated 33 million BTU per hour) was operated at about 25% load. After determining baseline NOx levels and oxygen excess, the aerosol delivery system of the present invention was installed and operated for 3 weeks. As a result, the boiler was found to be able to reduce excess oxygen by 45% and maintain it at 25% load, and thus fuel reduction was about 4%. The boiler's NOx level was reduced by 35% from 136 ppm to 87 ppm. The flame was described by the company's boiler engineer as the bluest flame that appeared to be the closest to a pure hydrogen flame.

1 is a schematic diagram illustrating a direct flame application according to an aspect of the present invention. 1 is a side view of an aerosol delivery system according to the present invention. FIG. FIG. 3 is a top view of the aerosol delivery system of FIG. 2. 6 is a side view of another aerosol delivery system according to another embodiment of the present invention. FIG.

Claims (18)

An aerosol delivery system for use with a combustion device,
A first inlet for supplying a source of gas to the chamber;
A second inlet for supplying the chamber with a catalyst solution comprising one or more inorganic metal salts in a solvent;
Comprising a chamber comprising an atomizing nozzle for releasing fluid in the form of an aerosol from the chamber;
The first inlet and the second inlet and the atomizing nozzle are arranged to mix and gas and fluid in the chamber together to form an aerosol when discharged through the nozzle; An aerosol delivery system, wherein the nozzle is in fluid communication with one or more of a pre-combustion zone, a combustion zone, and a post-combustion zone.   The aerosol delivery system according to claim 1, wherein the nozzle is present in the combustion zone.   The aerosol transport system according to claim 1, wherein the nozzle is present in a pre-combustion region where air and fuel are mixed prior to combustion.   2. The nozzle according to claim 1, wherein the nozzle is placed in a pre-combustion region in which only fuel exists and / or in a pre-combustion region in which only air exists before the two components are mixed. 2. The aerosol delivery system according to 2.   The aerosol delivery system according to claim 1, wherein the nozzle is placed after the combustion region.   The aerosol transport system according to claim 1, wherein the nozzle has a conical shape.   The aerosol transport system according to claim 1, wherein a plurality of nozzles can exist.   8. An aerosol delivery system according to any one of claims 1 to 7, wherein the supply of gas and catalyst solution to the chamber is continuous, so that aerosol is continuously sprayed from the nozzle.   The catalyst solution of the present invention is platinum, palladium, rhodium, rhenium, ruthenium, osmium, cerium, iridium, indium, magnesium, aluminum, titanium, copper, zinc, lithium, potassium, sodium, iron, molybdenum, manganese, gold, or 12. An aerosol delivery system according to any preceding claim, comprising one or more compounds comprising a metal selected from silver.   10. The aerosol delivery system according to any one of claims 1 to 9, wherein the compound is present in the solution at a concentration of 0.1 to 2.0 mg / ml. A method of burning fuel with a catalyst,
a) providing a catalyst solution and a compressed gas to the chamber, the chamber comprising a nozzle in fluid communication with one or more of the pre-combustion zone, the combustion zone, and the post-combustion zone;
b) mixing the solution and the gas in the chamber;
c) forcing the mixture of solution and gas through the nozzle to form an aerosol in the pre-combustion zone, combustion zone, or post-combustion zone of a fuel combustion device.   The method of claim 11, wherein the aerosol and the fuel can be introduced simultaneously or separately into a combustion zone of a fuel-injected diesel or gasoline engine.   13. A method according to claim 11 or 12, wherein the aerosol is introduced into a hot exhaust gas stream of a combustion system.   The fuel according to any one of claims 11 to 13, wherein the compressed gas is selected from air, steam, nitrogen, argon, helium, carbon monoxide, carbon dioxide, and combinations thereof. How to burn.   15. A method of combusting fuel with a catalyst according to any of claims 11 to 14, wherein the gas is placed under a pressure in the range of 30 to 90 psi.   16. A method for combusting a fuel according to any of claims 11 to 15, wherein the solution is placed under a pressure in the range of 20 to 70 psi. A method for pre-processing fuel,
a) providing a catalyst solution and a compressed gas to the chamber, the chamber comprising a nozzle in fluid communication with one or more of the pre-combustion zone, the combustion zone, and the post-combustion zone;
b) mixing the solution and the gas in the chamber, forcing the mixture of solution and gas through the nozzle to form an aerosol and pre-treating the fuel prior to combustion; Adding an aerosol to the solid fuel.   The method of claim 17, wherein the fuel is a solid fuel.

Images