MXPA06000002A - Method and system for process gas entrainment and mixing in a kiln system - Google Patents

Abstract

A method and system for mixing process gas flow by adding or in -jecting suitably-directed high momentum turbulent gas into dust -laden stratified process gas flow at approximately 850 to 1400°C to entrain the process gas flow such that stratification is reduced and mixing of both gases and suspended solids is im -proved. The jet entrainment of the process gas flow by appropri -ate injection of gas serves to enhance the contact of reacting materials, such as residual fuel and available oxygen, and fur -ther serves to improve the completion of reactions, such as com -bustion of the fuel and the transfer of heat to the raw mate -rial/kiln feed.

Description

METHOD AND SYSTEM FOR DRYING AND MIXING GAS FOR PROCESSES IN AN OVEN SYSTEM FIELD OF THE INVENTION The present invention deals with a method and system for gas entrainment for processes and mixing in a furnace system. More particularly it concerns a method and system in which a gas flow for process and which facilitates the combustion and removal of classes of chemicals present in the gas flow for process during combustion in a furnace system. BACKGROUND OF THE INVENTION Furnace systems are known to process cement clinker and various metallic and non-metallic minerals such as iron, gold and lime. In this application, the text focuses on kiln systems for producing cement clinker, however, one skilled in the art will understand that the presented concepts may have application in other types of kiln systems. Cement clinker is the material that, when in very fine powder forms cement, which is mixed with water and inert materials to form concrete and mortar. In cement clinker it is conventionally produced by heating raw materials at very high temperatures in a furnace system. There are various types of furnace systems known in the art, including wet long furnace systems systems and various types of furnace systems with preheater. The following arrangement will focus on preheater furnace systems, however, similar processes occur and similar difficulties may arise in long furnace systems. A conventional preheater kiln system used for the production of cement clinker usually consists of two sections, the preheater section and the kiln section. The preheater section consists of a gas riser and a series of turbulence burners, typically four or more in number installed in a vertical structure, where the last turbulence burner in the series advances to the furnace section through a feeding gutter. The oven section includes a tilted rotary oven, which provides primary heating for the oven system. The tilted rotary kiln includes a fuel inlet and spark plug in its lower part to heat the oven. In some kiln systems with preheater there may also be a secondary heating system in the gas riser or a pre-calcining kiln (which is also sometimes referred to as a kiln), supplied to burn most of the raw material before to enter the oven section. The precalcining oven can be placed between the preheating section and the furnace section, although it can also be part of a section of the preheater. For convenience, it is common practice to use a pair of turbulence burners in parallel at the highest stage of the preheater, and for high total efficiency systems, a single furnace may have a complete set of double burner turbine of preheater in series, being provided one or both of these preheater rows with a precalcination furnace gas or secondary heating system. In a preheater furnace system, a mixture of powdered raw material having the appropriate chemical composition (primary powder) is fed into the higher turbulence burner. The raw powder used in the production of clinker in a kiln system is traditionally prepared from natural quarry products that are mainly comprised of limestone (a source of calcium carbonate), which is calcined to be converted to lime during the treatment of heating. With release of carbon dioxide through an endothermic reaction, and slate (a source of silicates, aluminates and iron oxide). When necessary, local reserves of raw materials are supplemented with corrective amounts of components such as sand (a source of silica), bauxite (a source of alumina), pyrites (an oxide source) of iron) and / or limestone (often reserves with a very high purity) to prepare the raw powder. The raw material is finely ground and mixed to form the pure powder before it is added to the higher turbulence burner. The raw powder provides a mixture of basic chemicals that, when calcined and combined with fossil fuel ash or other fuels in the kiln system, allows the formation, in an aluminum-ferrite stream, of a mixture of calcium silicates and aluminates (called "clinker"). This is finely ground with the addition of a fixed control agent such as gypsum to form Portland cement and when mixed with water, silicates and aluminates undergo hydration reactions (ie set and increase in consistency to produce concrete or mortar). ). When the raw powder is fed into the higher turbulence burner it is dispersed and preheated by means of a gas flow emanating from the next turbulence burner down the series. Within each turbulence burner there is a whirlwind that disperses and collects dust. The vortex facilitates the movement of the powder from the first turbulence burner to the second turbulence burner in the series. As the powder goes down from turbulence burner to burner Turbulence is heated and partially can be calcined, and if there is combustible material present, part of it can be found in combustion, finally leaving a final mixture known as kiln charge. The vortex in each of the turbulence burners facilitates the movement of the powder down the series until it reaches the last turbulence burner. During the preheating stage, before the powder reaches the tilted rotary kiln, the temperature thereof rises to approximately 600 to 900 degrees Celsius. Once the raw powder passes through the last turbulence burner, it reaches the hearth of the furnace and (now referred to as "furnace charge") passes to the upper end of the tilted rotary kiln through a feed chute. When entering the inclined rotary kiln, the kiln charge can also be referred to as hot powder. The hot powder advances towards the lower end of the rotary kiln inclined countercurrently with the gaseous products produced during combustion of the fuel at the lower end of the inclined rotary kiln. As described above, the inclined rotary kiln has a call at the lower end of the inclined plane ("the flame zone"), which heats the contents of the rotary kiln. The temperature of the hot powder rises about 1450 ° C before going out the outer end of the rotary kiln. At this temperature the hot powder reaches a semi-molten state in which the chemical reactions, which form the clinker, are carried out. The temperatures of the flame and gas at the lower end of the tilted rotary kiln should be considerably higher than 1450 ° C to ensure that hot powder reaches this temperature. Once the clinker is produced at the end of the tilted rotary kiln it flows into the clinker cooler where it is cooled by air. The hot air produced from the clinker cooling can then be reused to heat other sections of the furnace system, such as the preheater or precalciner, in an effort to conserve energy. To move the hot air, the furnace system can be operated under negative pressure with exhaust gases pulled towards it under a current of air induced by a fan. The fan can be placed on or beyond the preheater outlet. In the furnace system, the process gases travel upwards through the rotary kiln, the rising gas conduit and the turbulence burners generally in countercurrent to the raw powder and can absorb many contaminants present. Before released into the atmosphere, the gases are typically dusted to meet the stringent regulatory limits and if necessary also cleaned of impurities such as NOx before being released into the atmosphere. A development in conventional preheater ace systems is that fuel combustion can also be carried out in the secondary heating system (as described above), by supplying appropriately prepared fuel for the rising gas conduit. This practice increases the performance of a ace system at the same time that it has little effect on thermal performance. In addition, it also raises the degree of decarbonisation (calcination) of the file entering the inclined rotary kiln, in turn reducing the thermal load in the ace flame zone and often reducing the volume of combustion gases, which flow towards the kiln. the rotary oven. The other development, the secondary heating can be extended to a greater degree in the oven systems adapted with a precalcining oven. A pre-calcination ace is a conventional combustion tank or ace that is located in or near the base of the preheater when it is food with the appropriate fuel and air, preferably preheater. The preheated air for the precalcining oven can be taken from the exhaust produced from the Clinker cooler, as described above. The preheated air can be moved through the rotary kiln in a "separate air" system, where it is practical to do so. Alternatively, the air can be received from the rotary kiln in an air passage variant. Other advantages can be gained with the operation of a precalcining ace, similar to those described above for heating the riser. One of the primary advantages is that the precalcining ace allows a greater scope and selection of the operating conditions, which in turn allow a reduction in the level of nitrogenous oxides (NOx) that pass through the preheater to the atmosphere. Another variation of a conventional oven system includes the use of a grid preheater system, which is commonly referred to as a "Lepol grill". At present, a mixture of crude, finely ground powder is formed in a pellets / beads by the addition of water to a rotating tilted pan. The pearls are then fed to the end of a moving grate where they are swept by the exhaust gases of the ace in order to be dried and preheated. The supplemental heating can be done in and after the ascending gas conduit connecting the upper end of the ace to the hot end of the grate, known as heating on the grate. This process it has benefits and problems analogous to those described for preheater systems with turbulence aces, such as the stratification of combustion gases in the various parts of the ace system. Clinker production uses natural resources intensively, both in terms of energy and raw materials. Due to the natural origin of the raw powder charge / kiln charge and fuels used in a kiln system, smaller amounts of other kinds of chemicals can also enter the kiln system. These other kinds of chemicals can enter in amounts that have adverse influence on the conditions within the ace system. In addition, ace systems produce an exhaust gas stream that requires cleaning to ensure that any potentially harmful chemicals that may be produced during the process are reduced in concentration before the gas stream is released into the extreme environment and atmosphere. Manufacturers are concerned about reducing their impact on the environment. For example, the use of select reserves is using alternative raw materials and / or fuels, such as secondary products from agricultural, process and commercial companies. These alternative substances can have a double role in a ace system. Some of the alternative substances that they are used as partial substitutes for raw materials they can have a fuel content in them and some alternative fuels can have an important content of ash, and as such they play a double role since these two are necessary in a furnace system. A consequence of using alternative substances instead of traditional ones, however, it may be that additional organic matter and carbon are present for combustion in the regions of the system different from the expected combustion in the flame zones. A disadvantage to using either a conventional fuel or an alternative fuel (before processing the crude fuel) is often the need for expensive and energy-intensive pre-preparation, examples of this would be the fine grinding of solids or the atomization of liquids . In accordance, there is a desire to use fuels effectively in the process and minimize the required preparation. Alternatively, there is another trend in the pipeline to use fuels that are more difficult to burn (due to their hardness, moisture content or adhesiveness) as long as no undue additional expenses are incurred in preparing them, and depending on whether their distribution and maintenance in a properly oxidizing gaseous medium (as required by its combustion characteristics). By way of example, this This tendency can be observed in the techniques established in several patents that address the introduction of used vehicle tires at the upper end of long furnaces that are generally not equipped with preheaters. An example is U.S. Patent No. 5,078,594, issued to Cadenee Chemical Resources, Inc., and Ash Grove Cement Company. The benefits of using alternative materials and fuels include reducing the demands of select reserves and eliminating the problem of otherwise disposing of waste and by-products and the concomitant effects on the environment. The furnace systems are well adapted for the use of various non-refined fuels or flammable pieces of low quality, since the ash can be assimilated into the clinker product. The reason for these is due to the fact that combustion occurs under controlled conditions and high temperature, with residence times important for the fuel particles at these temperatures. Various difficulties arise in the operation of conventional furnace systems, which include preheater furnace systems when using traditional fossil fuels prepared according to conventional methods and / or alternative fuels prepared by less conventional means As a consequence, there are limitations in the amount of one or more fuels, in a certain state of preparation, that can be supplied to a precalcining oven, rising gas conduit or upper end of an oven while still maintaining adequate clinkerization conditions. suitable at the lower / outlet end of the furnace system. Conventional preheater furnace systems may have one or more of the following difficulties: (a) accumulation of a solid material in the resulting system either in a partial or complete block; (b) an increase in the generation of one or more pollutants, such as NOx (or a limitation in the degree of reduction possible within the process); (c) an increase in energy consumption per ton of product and / or (d) a reduced production rate. Several of the above-mentioned difficulties have the additional advantage of limiting the possibilities of reducing the consumption of selected fossil fuels with a consequent additional limitation of the scope of reducing the generation and emission of greenhouse gases, such as carbon dioxide. Some of the difficulties, in principle, can be alleviated by more intensive treatment and fuel preparation, in addition to using more complex procedures for controlled delivery in the process. Implementing these solutions, however, is often not cost effective. Ideally, when more fuel energy is put into some part of the furnace system, such as a preheater riser duct, which is downstream with respect to the combustion products, from the main clinker deformation zone, the result it must be an increase in overall volume of solids consumption where there is either no change or only a small change in the temperature of the gases that emerge from that part of the furnace system. Higher gas outlet temperatures would suggest that the additional energy has not been efficiently applied in its entirety to heat the solid materials, but rather has been wasted in creating and heating the gases. The techniques directed to promote beneficial mixing of gases in furnace systems are known, however, the included momentum and turbulence levels are typically not large enough to be fully effective in the aerodynamic. Consequently, techniques that can have the most beneficial effect on gas flow and heat transfer to and from fuel and charge particles are not present in the parts of the process where they can best contribute to solve the problems that arise with respect to the conclusion of the combustion and other chemical reactions in the furnace systems. As such, there is a need for an improved method and system for the mixing of process gases in the furnace system in order to increase the combustion and environmental efficiency of the furnace systems. Summary of the Invention It is therefore an object of the present invention to provide an improved method and system for mixing process gases in furnace systems that address at least some of the problems identified above. In particular, one embodiment of the invention is a method and system for adding or injecting high-moment turbulent gas suitably directed to stratified process gas loaded with dust at about 850 to 1400 ° C to eliminate stratification and increase the mixing both process gases and suspended solids. Gas injection serves to improve the contact of reactive materials, such as residual fuel and available oxygen, also serves to improve the termination of reactions, such as fuel combustion and heat transfer to the raw powder / furnace / powder charge hot . The projected benefits of the form of embodiments of the invention include the increased substitution of fossil fuels, lower carbon monoxide emissions, lower emissions of nitrogen oxides, ammonia and dioxins, higher levels of petroleum coke, use and increased clinker production. According to an embodiment of the invention, there is provided a system for mixing a gas flow of processes flowing through a housing of a drying oven system, the mixing system includes at least one injector equipped in the housing and a gas supply system connected to at least one injector to supply the gas to the injector at a predetermined pressure, wherein the injector and the predetermined pressure are arranged and selected to inject gas into the housing at a sufficiently high moment to produce a jet having the appropriate characteristics of turbulent regime such that the process gas flow is carried by the injected gas. According to another embodiment of the invention, a system is provided for mixing a process gas flow flowing through a housing along a housing axis. The system includes an injector equipped in the housing and approximately on the shaft and directed in the direction of the process gas flow and a gas supply system connected to the injector for supplying gas to the injector at a predetermined pressure, wherein the injector and the predetermined pressure are positioned and selected to inject gas into the housing at a sufficiently high moment to produce a jet having the appropriate characteristics of the turbulent regime so that the flow of process gas is carried by the injected gases. In any of the aforementioned embodiments, the injector may be equipped with cyclonic deflectors, and in a preferred case, the cyclonic deflectors have an angle of approximately 10 to 35 degrees. As an alternative or in combination with the cyclonic baffles, the injector may also be equipped with flared diffusers and / or a flat-faced wide body to increase drag. Preferably, the flared diffusers are in mid-angles of approximately 5 to 20 degrees. In these embodiments, the system for injecting the gas is preferably arranged in such a way that the flow of process gas is drawn substantially before the injected gas flow is converted to piston-type expense along with the gas flow for process or before the flow of injected gas has an effect on the inside of the housing. According to another embodiment of the invention, invention, there is provided a system for mixing a process gas flow flowing through a housing along a housing axis, the system includes a plurality of injectors provided in the housing and arranged at predetermined intervals around a section transverse of the gas flow of processes and in communication with the interior of the housing, and a gas supply system to feed gas to the injectors at a predetermined pressure, where the injectors are directed to inject gas and incise tangentially in a centered circle of the axis of the process gas flow and cover at least approximately 5 to 15 percent of the cross-sectional area of the process gas flow. In particular, the plurality of injectors and the predetermined pressure preferably are arranged and selected to inject gas into the housing at a time sufficiently high to produce a jet having appropriate characteristics of turbulent flow so that the flow of process gas is entrained. by the gas injected. In this case, the process gas flow is preferably dragged substantially before the flow of injected gas is converted to gas flow together with the process gas flow or before the flow of injected gas impinges on the inside of the accommodation. In a preferred case, the circle covers at least approximately 5 to 10 percent of the cross-sectional area of the housing. In the above embodiment, the injectors may be equipped with cyclonic deflectors and, in a preferred case cyclonic deflectors having an angle of approximately 10 to 35 degrees. As an alternative in the combination with cyclonic deflectors, the injectors can also be equipped with flared diffusers and / or bodies with wide flattened front to increase the drag. Preferably, the flared diffusers are in average angles of approximately 5 to 20 degrees. In another preferred case, the plurality of injectors is directed towards an angle of approximately 0 to 60 degrees in the direction of the process gas flow. In this case, the plurality of injectors can also be preferably directed at an angle of approximately 25 to 40 degrees in the direction of the process gas flow. In another preferred embodiment, the plurality of injectors comprises a first group of injectors and the system further includes a second group of injectors that includes at least one injector that is equipped in the housing, placed in a second cross section of the housing and that is in communication with the interior of the housing and that at least one injector is directed to inject gas for incising tangentially in a second circle centered on the anchor of the housing having a different diameter than the circle of the first group of injectors. One skilled in the art will understand that the injection gas can be supplied to the second group of injectors by means of the same gas supply system as the first group of injectors or by a second gas supply system. Preferably, the second circle has a diameter larger than the circle of the first group of injectors and the second cross section is separated from the cross section of the first group of injectors in the direction of the process gas flow. . In the above embodiments, the injected gas can be, for example, air or oxygenated air or the like and the injected gases can be preheated depending on the particular application of the system. In the above embodiments, the system can be applied to a drying oven system for preparing hydraulic cement clinker and, in particular, can be applied with benefits in a region of the drying oven system where the process gas temperature it is between approximately 850 to 1400 degrees Celsius. Depending on the place of the system within the kiln systems to dry, for example, in a rotary kiln, the temperature of the process gas may preferably to be between about 1000 to 1200 degrees Celsius, while in a region near the gas outlet of a precalcining furnace the gas temperature may be between about 900 to 1250 degrees Celsius. Furthermore, when the system is applied in such a way that said system will improve the performance and the completion of the reactions with ammonia, the system is preferably applied to a region where the temperature of the gas is approximately between 850 to 1050 degrees Celsius. It should be understood that the various embodiments of the system can be applied to a housing in one or more locations in a drying oven system, for example in the preheater section including the rising gas line or the precalcination oven, a system of exhaust gas passage or in the rotary kiln. According to another embodiment of the invention, a method is provided for mixing a process gas flow of a furnace system that includes providing a high pressure injection gas source, and injecting the injection gas into the flow of process gas at moments sufficiently high to produce a jet having appropriate characteristics of turbulent regime so that the flow of process gas is carried by the injected gas.

According to yet another embodiment of the invention, a method is provided for mixing a process gas flow in a housing of a furnace system that includes providing a source of high pressure injection gas, and injecting the gas injection into the housing, so that the injection gas incisively tangentially in a circle centered on the axis of the process gas flow and covers at least about 5 to 15 percent of the cross-sectional area of the process gas flow. In a preferred case of the two embodiments. mentioned above, the method may include imparting eddy movement to the injection gas as it enters the housing, for example, using cyclonic deflectors. Alternatively or in combination, the turbulent regime and entrainment can be improved by using flared diffusers and / or bodies with crushed wide front. In another preferred case, the total moment of the injection gas during the injection is approximately 50 to 150% of the moment of the process gas flow. In another preferred case, the injection gas is injected at or more than about 150 meters / seconds. Preferably, the Reynolds number due to mixing is increased by approximately 2.5 times higher than that found in a process gas flow typical without the mixture and in a similar region of a furnace system. In addition, the turbulent frequency due to the mixture preferably increases by approximately 100 times higher than that found in a typical process gas stream without mixing. Still further, it is preferable if the total momentum, turbulence and whirlwind movement of the injected gases are selected based on an aerodynamic calculation and / or mathematical model indicating that the injected gas would be substantially entrained in the entire gas flow. of processes. Other embodiments of the present invention include a rotary kiln, precalcining furnace, exhaust gas passage system, riser gas conduit or other appropriate component of a kiln system having the system for mixing a process gas stream. described above applied to it. The mixture provided by the injection of gas results in an increase in the combustion of solid fuels in pieces (such as tires, wood chips and plastics) to stimulate total combustion, controlled and non-polluting with the release of energy. The mixture provided by the injection of gases also increases the heat transfer from gas to particle and makes better use of the oxygen available in a furnace system. Other aspects and characteristics of this invention will be apparent to those skilled in the art at the time of reviewing the following description of the specific embodiments of the invention together with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS Embodiments of the present invention will be more clearly understood with reference to the following description of the preferred embodiments and drawings, wherein: in Figure 1 illustrates a furnace system with preheater; Figure 2 illustrates vortex air systems ("SAS") according to the embodiments of the invention as applied to the preheater furnace system of Figure 1; Figure 3 illustrates a vortex air system placed in a precalcination furnace between tertiary air inlets and loading according to an embodiment of the invention; Figure 4 illustrates a transverse vertical view of the vortex air system with injectors positioned on the periphery of a section of the rotary kiln, - Figure 5 illustrates a cross-sectional view of a vortex system placed in a conduit carrying dust-laden gases; in a furnace system; Figure 6 illustrates a vertical transverse view of a vortex air system comprising two vortices of concentric counter rotating turbulence according to another embodiment of the invention; Figure 7 illustrates a transverse side view of the vortex air system of Figure 5; Figure 8 illustrates a transverse vertical view of a portion of a precalcining furnace; which forms part of the preheater furnace system comprising two vortices of concentric counter rotating turbulence according to another embodiment of the invention; Figure 9 illustrates a portion of a furnace system that includes the vortex air system of the figure 8; Fig. 10 illustrates an injector for the vortex air system of Fig. 6 and 7; Figure 11 illustrates a portion of the furnace system that includes a vortex air system according to another embodiment of the invention; Figure 12 illustrates a furnace system with secondary heater preheater supplied to the riser gas conduit including two possible locations for a vortex air system according to the embodiments of the invention; and Figure 13 illustrates a furnace system of separate air calcination including two possible places for a vortex air system according to the embodiments of the invention. DETAILED DESCRIPTION Figure 1 illustrates a typical preheater furnace 20 having a preheater section 22 and an oven section 24. Preheater section 22 includes a raw powder feeder circuit 26, which feeds the raw powder to the upper turbulence burners 28a, 28b of a series of interconnected turbulence burners 29a, 29b and 20 through which the raw powder passes, an ascending gas conduit 34 conveying the gases from the section of furnace 24 towards the turbulence burners, and a forward rack (or furnace hearth) 38, which is connected to the lower turbulence burners and also connects the section of the preheater 22 to the furnace section 24. The section of The preheater also includes one or more fans of applicators 36, which maintain appropriate pressure levels within the preheater section 22 and the rotary kiln 42. The section of. Rotary oven 24 includes an inclined rotary kiln 42, which is connected via a seal 44 to furnace hearth 38 at an upper end 46 of the rotary kiln 42, and a fuel charge 48, which is provided at a lower end 50 of the kiln rotary 42 and supplies fuel to provide a flame 40 for heating the interior of the rotary kiln 42. The kiln section 24 also includes a clinker cooler 52 which is connected through a seal 54 at a lower end 50 of the rotary kiln 42 near the fuel load 48. In the operation, the crude powder travels through the raw powder feed circuit 26 and enters the first series of turbulent burners 28a and 28b. The raw powder is collected from the turbulence burners 28a and 28b by vortexing and travels in a conduit 56 which is connected at the base of the turbulence burners 28a and 28b and then continues to enter a subsequent turbulence burner for redispersion in the gas stream. Eventually, the raw powder reaches feed 28 by the action of gravity and turbulence burners. At the same time that the raw powder traverses the preheater section 22, the hot process gases from the furnace section 24 rise through the ascending gas conduit 34 and through the turbulence burners in a normally reverse direction to the flow of the raw powder. As such, the raw powder is heated while it is dispersed at each stage in the hot process gases, which come from the turbulence burner below or through the ascending gas conduit 34 of the oven section 24. The hot raw powder in the shelf of food 38 (sometimes called oven charge) then enters the oven section 24 at the upper end 46 of the rotary kiln 42 where the kiln charge (now referred to as hot powder) continues to travel through the rotary kiln 42 by gravity and by rotating the rotary kiln 42, promoting mixing by sliding and tumbling. The hot powder continues to heat through this process undergoing chemical reactions and forming the clinker that eventually reaches the lower end 50 of the rotary kiln 42 where it is discharged into the clinker cooler 52 and is cooled by means of an air stream. This air stream is typically also used in other parts of the furnace system 20 to make use of the heat contained in the air after exposure to the clinker. In this conventional preheater 20 furnace system, additional fuel can also be added in the riser 34 or in the feed rack 38 of the preheater section 22 to provide additional pre-heating of the raw powder before it enters the kiln section 24. Some of the fuel can also be added directly to the upper end 46 of the rotary kiln 42, for example, used tires. In a kiln system, the combustion of Fuel and the chemical reactions that occur in the raw powder and hot powder result in the release of various kinds of chemicals in the process gas flow within the furnace system. Classes of minor chemicals in an oven system include compounds that contain elements such as chlorine, sulfur, sodium and potassium along with other elements within the same families. These are volatilized to a greater or lesser extent in the hottest regions in the furnace system and are transported in the process gas stream (sometimes referred to as "process gas flow") to the colder regions where they are condensed and where they can form solutions with low melting temperatures. The volatile classes can then join particles of solid feed material and join the pipeline of the furnace system. This process can lead to partial and / or larger seals and as a result the kiln system will require cleaning or other intervention to maintain adequate production. In some situations a permanent set of air sanders can be installed to reduce the problem of clogging. After condensing, some volatile classes that do not bind to the pipeline can travel down hot from the furnace system again and experience the volatilization process again. This cyclic pattern can increase the concentrations of volatile classes and aggravate the concomitant problems. The degree of volatilization of the compounds can be affected by the following: (1) the composition of the local gaseous atmosphere; (2) come into contact with other kinds of chemicals in the fact of solids; (3) the temperature of the furnace system; and / or (4) the behavior at the time of condensation, for example, the decomposition of calcium sulphate is affected by concentrations of oxygen and carbon monoxide, by contact with solid carbon, and by temperature. The decomposition of calcium sulphate can have unfortunate consequences when the amount of sulfur entering the furnace system is greater than that which can enter in combination with available alkalis (combined with non-halides) as alkali sulfates. When this happens, the excess sulfur tends to react to form calcium sulfate or potassium calcium sulfate otherwise known as "calcic langbeinite" which can decompose and volatilize as local conditions vary. It is preferred that the sulfur leaves the kiln with the product of the clinker in a chemically combined stable state, instead of composing, volatilizing and aggravating the recirculation, the phenomena of accumulation and obstruction. When extreme levels of circulating volatile compounds are encountered, it may be necessary to adapt a pass-through system (exhaust gas passage system).

This involves purging a fraction of the exhaust gases from the rotary kiln of the riser gas conduit through a discharge pipe 80 of an exhaust gas passage system (not shown), rapidly cooling it to condense the volatile compounds and then the Remove in a separate gas cleaning system that deviates from the preheater section. Under certain conditions, halide classes can be precursors in the formation of organic pollutants. Such conditions may exist when there are traces of organic ampurities released from the pure powder and fuel that are being preheated. If there are adequate conditions of temperature, residence time and concentrations of chemical classes, then undesirable contaminants could form and potentially get lost in the atmosphere once they are condensed into dust or vapors. When oxidizing gases are not immediately available, the residual carbon ("lower quality coke") of traces of solid fuel within the components of raw materials or the unrefined or lumpy fuel that is used in secondary heating or of the precalcining furnace sometimes persists throughout the preheater 22 and enters the inclined rotary kiln 42. The combustion of the residual lower quality coke then produces local reduction conditions for the sulphate, aiding volatilization and inhibiting condensation. To avoid this occurrence, attempts have sometimes been made to operate the furnace system with a higher level of excess air than otherwise required. The additional air aids in the combustion of lower quality coke but leads to energy losses due to the related heating of the nitrogen in the additional air. This adversely affects the clinker production potential when production is limited by the capacity of the induced current exhaust fan 36. Inadequate combustion in a secondary heating system, such as the pre-calcining furnace 58, may also be a source of residual lower quality coke that passes to the rotary kiln 42. The heating of the rising gas conduit typically does not achieve useful benefits in the total efficiency of the kiln unless there is adequate heat transfer to the solid material being processed. In practice, this is observed for heating up to about 10 to 15% of the fuel in furnace systems where replacement of the furnace fuel by pulverized coal or good quality oil in the secondary heating stage is used. When heating up the riser gas duct is implemented, higher levels of excess air may need to be used to address other "difficult" fuels that are not very volatile, such as petroleum coke (known as "petcoke"). Higher levels of surplus air work in the present to ensure total combustion while keeping the probability of accumulation acceptably low, but, as discussed above, it brings a waste of energy by heating large amounts of nitrogen in the air surplus, as well as a performance reduction in the furnace's rate of return. In addition to the above, when very low quality fuels are used, the additional air also needs to be passed through the kiln system which causes a reduction of the temperature of the main flame 40. As a result, part or all of the extra energy it will not be transferred to the raw material and raw fuel, which in turn results in a greater volume and temperature of the exhaust gas being operated by the induced current fan 36. If the current fan 36 lacks the - ability to cope with the new work required, may also present a bottleneck in the furnace system 20 with respect to increased rates of yield. In this situation, transient crests of carbon monoxide can also be observed due to the quality of the fuel or variations in the speed of the load, resulting in a generally higher level of carbon monoxide emissions from the system. The carbon monoxide resulting from incomplete combustion will tend to rise towards the upper layers of gas within the rotary kiln 42 and will not mix positively to react with the residual oxygen present. Contrary to carbon monoxide, carbon dioxide tends to concentrate to a greater degree near the solid event 66 in the rotary kiln 42. By leaving the section of the rotary kiln 42, the stratification of the gas may persist in the lower regions of a preheater and the heating system of the riser. The stratification does not aid the rapid complete combustion of the crude fuel and more particularly the fuel in lump aggregate to the feed rack of the furnace 38 or when it is allowed to fall to the solid 66 at the upper end 46 of the rotary kiln 42, which on occasion It is the practice for materials such as used tires. The volatile chemicals released from a fuel in lump as it is ignited and burned enter the flow of process gas and typically do not have the opportunity to react with all traces of oxygen present until they are subsequently mixed in the preheater section 22 or the 58 pre-calcining oven. This occurs frequently at lower temperatures and as As a result, traces of volatile hydrocarbons may occasionally emerge into the atmosphere as unwanted contaminants. Unwanted contaminants may also be accompanied by higher than desired traces of unburned carbon monoxide. As described above, the conventional solution is to operate the furnace system at a higher level of excess air. This also has potential drawbacks which may limit the amount of lump fuel that can be added at the upper end 46 of the rotary kiln 42. A possible solution is to enrich the combustion air oxygen content (very rarely an economic proposition). ) and / or undertake major and costly reconstruction and expansion of furnace hearth 38 (if possible) with a concomitant loss of production during modifications. Another drawback of using scrap fuels is that they can limit the potential use of high sulfur fuels in the process, such as petcoke due to their influence on deposition, volatilization and sulfate removal. . Said petcoke is often cheaper to obtain since it can not be easily used in some types of heaters and processes that do not inherently absorb the additional sulfur. There is a need to obtain a more complete and uniform combustion of the lower quality coke, carbon monoxide and the volatile material of "difficult" alternative fuels and avoid the operation of furnace systems at unduly high levels and waste of excess air that can undermine the total yield. At present, "difficult" refers to the idea that almost all alternative fuels have one problem or another, either due to the residual carbon caused by the initial size or the lack of volatile material (tires, wood chips, petcoke ), sudden volatile release due to either feeding (eg, whole tires or bags / bales of commercial waste) or high volatile content (eg drilling chips) or slow burning (eg coconut husks, petcoke) In addition, it is possible that the concentrations of carbon dioxide in the boundary layer of process gas around the raw powder and the fuel in the kiln 58 precalcining is high, as well as the high levels of carbon monoxide in the process gas surrounding the fuel particles, due to the process gas flow and the turbulence conditions that normally prevail. or carbon monoxide may require the operation of the precalciner 58 (see Figure 13) at temperatures that are higher than ideally convenient from the point of view of the total yield and reactivity of the material. The times of residence for effective mixing and combustion in many existing pre-calcination furnaces 58 are not sufficient to allow the oxidation of all carbon in solid low-combustion fuels. Increasing the temperature in the pre-calcination furnace 58 will also increase the exit temperature and change the location of the regions where volatile materials condense, often to non-accessible areas. The stratification of the process gas may occur within the conduits leaving a pre-calcination furnace 58- and in the same pre-calcination furnace 58. Improper mixing in a pre-calcination furnace 58 may lead to an increase in the temperature of the process gas which leaves the pre-calcination furnace 58 for an apparently unchanged level of calcination of the crude charge. This is the average result of a non-uniform mixture of overcalcined and / or subcalcined material that may eventually adversely affect the clinkerization reactions as well as the patterns for sulphate deposition. As a result of stratification, attempts to reduce the concentration of nitrogen oxides ("NOx") through re-burning reactions that include fuel injection in appropriate process areas may fail to achieve their full potential, driving back to the possible undesirable and unnecessary emissions. The NOx annealing reaction includes the introduction of fuel and volatile materials into an oxygen deficient process gas stream at a temperature between about 1000 to 1400 ° C. The reaction is. more efficient at higher temperatures and lower levels of local stoichiometry. Another method to reduce NOx is by using a combustion in stages. This is achieved by allowing volatile substoichiometric combustion of the fuel, then introducing the rest of the oxygen to complete the combustion, serving to reduce the concentration of NOx formed from the reaction of "NOx from fuel - oxidation of nitrogen in the fuel" . In the appropriate mixture of the solid and gaseous components in the reaction is beneficial, both before and after the graduation. For the further reduction of NOx, a selective non-catalytic reduction ("SNCR") method can be used with the injection of appropriate amounts of ammonia or ammonia compounds (or solutions of these) at an appropriate temperature and in the presence of certain oxygen concentration index, since this gas participates in the chemical reaction as stipulated: 2NH3 + 2NO + 0.502 2N2 + 3H20 The active component is the radical of NH2 *, which can also be supplied by alternative reactive agents. In theory, the optimum temperature range for efficient reduction is approximately between 850 to 1050 ° C. In practice, this is not always possible to ensure adequate complete reaction of the injected ammonia by providing sufficient residence time for the reaction molecules under the appropriate conditions of temperature and gas composition. A consequence will be the emission into the atmosphere of unwanted traces of ammonia and / or not being able to obtain the emission level of the nitrogen oxides below the desired level. The ammonia emission presents a double problem since it can 'violate the operation permits as well as lead to the formation of a dark colored plume over the chimney flue. This occurs according to the gases emitted are cooled, through the formation of a fine vapor of ammonia salts (usually sulfate or chlorine) which is very effective in scattering light. It has also been observed that the use of fuels that are difficult to burn in secondary heating systems, such as coal in pieces, or of fuel that is incompletely burned in the precalcining furnace 58, can be associated with the detection of dioxins and / or furans in the dust from an exhaust gas passage system, which allows the furnace operator to purge a fraction of the exhaust gases as described in more detail above (where a proportion of the gas stream is extracted, cooled and dedusted for volatile condensed compounds removed). This is attributed to the non-burner fuel, such as carbon or volatile materials, which are brought to the discharge pipe 80 and the exhaust gas passage system and which act as impellers for the de novo dioxin synthesis reaction. It is convenient to prevent such transfer and use the fuel energy productively. There is a variety of geometrical designs of preheater 22 (including turbulence conduits and burners) and precalciner 58 which can be connected to an inclined rotary kiln 42. The use of any specific variant in these descriptions is not intended to limit the shape embodiment of the invention, if not only indicate the general principles that can be applied to solve the problems in a furnace system. The same is true for the variety of fuels that can be used and the methods of preparing and delivering fuel to the furnace system. In addition, although the descriptions are generally made based on a symmetrical distribution of the equipment, sometimes the difficulties in practice may prevent this from being achieved in a particular place, and in such circumstances appropriate adaptations may be necessary. Again, these variations are not intended to limit the scope of the invention. As will be evident from the following text, it is useful to examine and try to overcome some of the problems in conventional furnace systems through fluid dynamics. A vortex air system ("SAS") 82 according to an embodiment of the invention will first be described generally with reference to Figure 2 and then described in more detail. Generally speaking, a SAS 82 according to one embodiment of the invention is a system for injecting gases into the gas stream of processes at time and turbulence sufficient to jet a substantial portion of the process gas stream to provide mixing of the process gas stream and reduce or eliminate stratification within the process gas stream. As shown in Figure 2, a SAS 82 can include either a single injector 84 or multiple injectors 86 and can be placed in various places within the furnace system 20. In a particular embodiment, an injector 84 is placed in the axis of the furnace system, pointing at the flow direction of process gas (an axial SAS) 88. The injector 84 is configured to create a cyclonic swirl 90 within the process gas stream to cause mixing of the process gas stream. In this example, the axial SAS 88 is positioned axially towards the upper end 46 of the rotary kiln 42, where the gas temperature is approximately 1200 ° C. In another embodiment, which also appears in Figure 2, multiple injectors 86 can be placed around the periphery of a housing 92 of an element of the furnace system 20, for example, the ascending gas conduit 34, for injecting gases along the process gas stream (a peripheral SAS) 94. In this case, the injectors 86 may have an angle towards a specific central or tangential location, for example, for a virtual circle of 0.3R (10% of area) at the center of the process gas flow, to create a free initial swirl 96 that decreases with additional turbulent mixing for a Swirl Ranking. In addition, the injectors 86 can possibly be tilted in the range of 20 ° to 60 ° pointing upwards in the direction of the process gas flow. This arrangement allows NOx annealing to help eliminate or reduce these gases. In general, an SAS 82 embodiment can be placed in many areas of the furnace system 20. example, in the gas riser 34, the pre-calcination furnace 58, the exhaust gas passage exhaust pipe 80, or the rotary kiln 42. In these cases, the SAS 82 may also be referred to as a "SAS of preheater "," SAS of ascending gas duct "," SAS of precalcining oven "or similar. Typically the details of each design of SAS 82 will be specific to the process and the plant but with preference based on the rules of the dynamics of the fluids for jet drag. Each SAS 82 is designed using jet drag equations • to provide. Generally advantages to the particular installation of interest. As an example, in the axial SAS 88, all of the downstream process gas of the axial SAS 88 is generally and fully drawn into the jet stream before the new piston-type expense region. At Peripheral SAS 94, a relative proportion of all the process gas is generally carried to each sprinkler before its meeting point in the central toroidal swirl 96, for greater mass and heat transfer (for example, a quarter of the gas flow of process for each of the four injectors). As an example, the dynamics equation of the fluids that are used can be: Mj / Mo = [Kl (K2 + K3 * S) x] / [Do * (Tf / To) ^] Where: Mj, Mo Total mass in sprinkler at distance x, initial mass in sprinkler. Kl Constant, depending on the size of the body with crushed broad forehead and the degree of cross flow, range 1 to 1. 4; K2 Constant - 0.35 (experimentally derived) K3 Constant - 4 (experimentally derived) S Vortex number of the injector X Axial distance Do Diameter of the effective injector Tf Temperature of the liquid to be drawn To Temperature of the liquid in the jet The calculation of the actual design for the specific embodiments of SAS 82 it can be determined alternatively using computational fluid dynamics ("CFD") techniques. However, at the time of writing, CFD probably only value the value of comparing the effects of possible changes with the geometry or operation of an existing system because CFD is not able to predict or model vortical flows so applying the above equation due to the current inability of the turbulence models available for excess vortex fluid flows.

As described above, the SAS 82 is equipped to inject a high momentum vorticial turbulent stream of air (or other gases) into the gas stream of stratified gas and particle in an area having a temperature of about 850-1. 00 ° C in an oven 42, the ascending gas conduit 34, precalcining furnace 58 or the like, in order to mix the process gas flow, remove the stratification and improve • combustion and heat transfer from gas to particle, making better use of the available oxygen . The additional air - usually with a moment level similar to that of the gas flow of the main process, arrives through injectors 84 or 86, designed specifically for the plant of interest. In a preferred embodiment, the injectors 84 and 86 can also be configured to induce vortex motion or turbulence in the injected gases and thereby improve the entrainment of the process gas flow. Figures 4 and 5 show alternative arrangements of the peripheral SAS 94, wherein cyclonic baffles 100 are included within the injectors 84 and 86. The injectors 84 and 86 can also be provided with a flat-faced body squashed (not shown) or diffuser flared (does not appear). A body with a flattened wide front is a centrally placed solid disk or cone near the outlet of the injector 84 or 86 of maximum diameter slightly smaller than that of the 84 or 86 injector. The body with flattened wide front or flared diffuser further increases the jet drag. There are several advantages that can be observed when using a SAS 82 with a typical process gas flow. By way of example, the Reynolds number, which indicates a turbulent regime and mixing, is expected to be approximately 2.5 times higher in some 7.5 * 105 than in a typical main process gas flow, thereby increasing the turbulent mixture . In addition, the size of the minimum expected turbulent stream is approximately 50 times smaller, i.e., smaller than the size of pulverized coal particles and raw material (approximately 3 microns), thereby increasing heat transfer for both the combustion as for calcination. The turbulent frequency, which indicates the rapidity of fluctuations in the turbulent flow, is also expected to generally increase approximately 100 times or more than perhaps 1.5 * 105 sec-1 to 5 * 107 sec "1, facilitating the mixing again In addition, the jetting and mixing due to the cyclonic deflectors 100 and / or flared diffuser or body with crushed wide front is expected to be approximately 2.5 higher at a specific distance than for the injection without those elements to the same speed, that way the amount and pressure of the fan can be reduced for the same effect and give a more beneficial impact both in the installation and in the process. It should be noted that normally, in the cement kiln systems, the values of the Reynolds number, the size of the turbulent stream and the turbulent frequency such as the above are only found in the "main furnace flame" zone. illustrates the peripheral SAS 94 according to an embodiment of the invention As described above the peripheral SAS 94 can be applied to the rising gas conduit 34, the pre-calcining furnace 58 or the rotary furnace 42 in the furnace system 20 As shown in Figure 3, the peripheral SAS 94 includes four injectors 86 directed towards and through the process gas stream that is flowing through the ascending gas conduit 34 or the precalcination furnace 58. in particular, the four injectors 86 are directed tangentially to the circle 0.3R 98 which represents approximately 10% of the area through which the process gas flows (in goose) sions referred to as a "virtual circle" since this is a target area within the process gas flow rather than an element of the furnace system 20).

In this embodiment, the gases are injected tangentially at a high momentum level to eliminate the stratification of the gases at temperatures ranging from about 850 to 1400 ° C. This embodiment of the invention also improves combustion, other chemical reactions and heat transfer for solids, such as raw material and crude fuel in the furnace system. An important factor in eliminating the gas stratification that can lead to other improvements, is to achieve the jet drag of the majority of the process gas stream (preferably over 80% and ideally 100%) in a new current pattern where turbulence increases and predominates, at favorable temperatures for chemical reactions. The concept is to create a free vortex flow mixed in jet of all process gases that then decrease with additional turbulent mixing for an intermediate swirl. The direction of the gas injection preferably is not directly axial or directly orthogonal to the flow direction of the process gas stream. The gas injection is preferably directed tangentially from several injectors to one or more virtual circles centrally located within the process gas flow. Virtual circles must cover at least approximately 5% of the cross-sectional area of the gas flow for processes in the injection region. The injected gas may be air or oxygenated air, perhaps preheated and optionally directed at an angle of up to about 60 ° to the axial direction of the gas stream. In addition, the gas injection can be carried out through injectors 86 optionally adapted with cyclonic deflectors 100 at angles of about 10 to 35 °. In addition, bodies with wide squashed front or flared diffusers mean angles of approximately 5 to 20 ° can also be added for the increase of jet drag. In a particular case, bodies with crushed wide front or flared diffusers can be applied alone (ie without cyclonic deflectors), if the cyclonic baffles at the end of the injectors are subject to obstructions that can affect not so severely a simpler device . As will be understood by a person skilled in the art, suitable materials for the construction and protection of the injectors 84 and 86 in the furnace system 20 should be considered, for example, steel alloys and / or refractory ceramic products that can withstand high temperatures They are convenient. Internal self-cooling systems (not shown) can also be included. It may also be beneficial to include suitable mounting systems to facilitate maintenance and cleaning of the injectors 84 and 86 in the oven system 20.

For example, cleaning mechanisms can be added to loosen any accumulation of classes of chemicals, process vapors and / or powders that adhere to a portion of the SAS 82 within the furnace system 20. In addition, when the injectors 84 and 86 do not They protrude very far into the gas flow for processes and have openings near the inner lining of the housing, it may be necessary to adapt traps for solid particles together with an automatic means of removing the trapped material. It will also be understood that SAS 82 will include a gas feed system 102 (see Figure 8) that includes a fan or fan (not shown) (ie, air source) by injector or an air source for several injectors. The injected gases are preferably reused from other parts of the furnace system 20 or from other parts of the cement manufacturing process, when available. As a general guide, the moment of the gas required for the correct mixing of the gases for processes is approximately 50 to 150% of the gas flow for processes. In order to minimize the amount of excess air injected into the system, the velocity should be as high as possible, with a lower limit of approximately 150 m / s and preferably sonic or higher. As a general guideline, the approximate design criteria for a SAS 82 is a moment around 10 N / MW and the capacity to drag up to approximately 15 times the mass of the injected jet before reaching the center of the process gas stream (for injection at or near the walls of the process tank) or reach the furnace walls (for injection at or near the shaft). This involves a similar level of mixing energy to that used in a high-moment pulverized fuel burner for a furnace or boiler. Preferably, the injection should be at sonic speed or higher, if possible, and be commensurate with the available fan pressure. A more detailed SAS design is based on the laws of jet drag. for vortex regimes and bodies with crushed wide front, which take into consideration the geometries and individual mass flows of the furnace, calciner, preheater, etc., and which is directed to achieve complete mixing through the entrainment of the gas stream for relevant processes, before the relevant incident points with either the rotary kiln or with other jet streams. Preferably, directing injected gases from various points towards the circumference of a virtual circle occupying approximately 10% of the central gas flow area will generally create a central mixing vortex. Add weak axial turbulence to the injected gases it will increase the mixture in an additional way, while avoiding the creation of an internal recirculation zone. For a more beneficial effect, the gases must be injected into openings flush with the walls of the furnace system so that they can cross the maximum possible length of length within the process gas stream. However, some protrusion of the injectors may be desirable to avoid clogging in situations where solid particles could enter the injectors if they are not kept out by the aerodynamics of the incoming gases or when there are external obstacles that make it impractical to have long Straight lengths of Injector outside the region of the furnace system of interest. Figures 6 and 7 illustrate another embodiment of the peripheral SAS 94. In this embodiment, a first turbulent vortex 96 is generated as described above through injectors 86 directed to tangentially impinge on a virtual circle 98 of about 0.3. R and is supplemented by a turbulent vortex of concentric counter rotation 101, which is created by additional injectors 103 directed tangentially towards the circumference of a second virtual circle 104 of the gas stream for processes. In this case, the injectors 86 can be directed to a smaller diameter circle 98 located upstream in the gas flow for processes, such that an internal vortex 96 can develop before penetrating the larger diameter counter rotating vortex 101 created by additional injectors 103 directed toward the larger virtual circle 104 as it expands to envelop the process gas flow peripheral exterior. This will create both intense central mixing and extreme turbulence at the limits of the vortex. As discussed above, cyclonic deflectors 100 can optionally be used with nozzles to create even greater turbulence and bodies with crushed wide front or flared diffusers can also be added to further increase drag. Figures 8 and 9 illustrate a peripheral SAS 94 according to this embodiment of the invention. Figure 7 illustrates a cross-sectional view of a portion of a pre-calcination furnace 58, which forms part of a furnace system 20. In this case, the pre-calcining furnace 58 has a housing 92 that is circular in shape and conical inwardly. at its lower end. The pre-calcination furnace 58 includes two coil lines 110 for feeding the fuel in the housing 92. The peripheral SAS 94 is equipped to the housing 92 and includes a set of four injectors 86 directed tangentially to a virtual circle 98 located in the center of the pre-calcination furnace 58 and covering approximately 10% of the area of the gas flow for processes. These injectors 86 induce the rotational movement of the gas flow for processes traveling through the precalcining furnace 58. The peripheral SAS 94 further includes a group of two injectors 103 directed tangentially to a second virtual circle 104 in the center of the precalcining furnace. 58 which is approximately twice the area of the first virtual circle 98. In a preferred case, the injectors 103 are axially offset along the gas direction for processes by a distance of about one radius of the precalcining furnace of the first circle, 98. These injectors 103 are arranged to induce turbulence in counter rotation of the process gas flow to the turbulence produced by the group of four injectors 86. The peripheral SAS 94 further includes a gas supply system 102 for delivering the injection to the injectors 86 and 103. Figure 9 shows an elevation of the precalcining furnace 58 which shows that the injectors 86 are directed at an upward angle of about 30 ° in this particular embodiment. Figure 10 illustrates an injector 86 of the type included in the SAS 82. The injector includes a valve 112, a pressure sensor (not shown - preferably installed in the set of nozzle parts, just outside the the wall of the pre-calcination furnace tank) and a nozzle 114, which extends through the housing 92. In particular, some benefit can be obtained by having the outlet of the nozzle flush with the interior of the wall of the housing. The injector 86 may further include an intake port 116 for compressed air to purge the injector 86 from any potential obstruction or equivalent. As discussed above, depending on the embodiment of the furnace system type, the injector 86 may also be equipped with cyclonic deflectors 100 or, optionally, a. body with crushed wide front (does not appear) or a flared diffuser (not shown) to increase drag additionally. In order to exemplify the principles included, consider the group of chemical reactions included in NOx annealing where a preheater of an oven system 20 with an index of 2000 tons per day has NOx emission from the rotary kiln 42 to the preheater section 22 of 1200 ppm. If the emission in the chimney of the furnace system 20 is below 500 mg / Nm3 (corrected for an oxygen concentration of 10%, on dry basis), part of the solution is to substantially reduce the NOx generated in the oven. In this example 20% of the fuel secondary to the gas stream for processes that has arisen from a primary flame operation in the level of 10% excess air. The resulting stoichiometry will be 0.85, which approaches the optimum level of 0.88 for NOx reduction in a second residence time of 0.5 at a temperature of about 1200 ° or more preferably 1300 to 1400 ° C. To ensure intimate contact of the classes of chemicals involved after the annealing reaction, SAS 82 can inject air to produce stoichiometry up to 110% and ensure effective oxidation of carbon monoxide and residual hydrocarbons. The gas flow rate for processes for approximately 10% of excess air can be calculated from the combustion of the fuel and the loss of carbon dioxide from the calcined raw fuel. The gas velocity for processes at a certain temperature can then be evaluated for a given conduit diameter depending on its moment. If this is used as the target total SAS time, a minimum required injection speed can be assessed from the additional amount of air needed to reach the total excess air supply of 15% and assuming an injected air temperature of 20 ° C. Figure 11 shows the axial SAS 88 in more detail. The axial SAS 88 is useful to avoid probable problems with obstruction of the localized injectors with the inner liner of the rotary kiln (ie those on a peripheral SAS 94) because the axial SAS 88 includes an injector 84 which is centrally located in the rotary kiln 42 and has the same direction as the gas flow for processes (opposite towards the raw powder). In this case, the injector 84 is preferably equipped with cyclonic deflectors of 30 ° 100 and can also include a flattened wide front body or flared diffuser (as discussed above) and the injected air is provided with sufficient moment to entrain the flow of gas for processes as much as possible before the point of incidence on the furnace wall. This helps to ensure that the carbon in the process gas flow is burned off and allows the high sulfate-based buildup in the furnace system 20 to be prevented. As shown in Fig. 11, the injector 84 may additionally be equipped with a cleaning device 118 for removing any accumulated deposit that may block the injector 84. Figure 12 illustrates the location of an SAS 120 or SAS gas ascending 122 (either either an axial SAS or a peripheral SAS) in relation to the overall structure of a preheater 20 furnace system. In some cases, it may be useful to have the SAS 82 in both the rotary kiln 42 and the ascending gas conduit 34, for example, when attempting to use used tires.

In an annealing reaction, a furnace SAS 120 can help avoid accumulation problems and a gas riser 122 SAS can help bring in additional air to prevent CO formation. If the SAS 82 is applied to the rotary kiln 42 it is preferably placed in an area where the temperature of the gas is approximately 1200 ° C. Figure 13 illustrates the location of SAS 120 furnace or SAS 124 calciner relative to the overall structure of a separate air pre-calcining furnace system 126. In Figure 13, furnace system 126 includes a tertiary air duct 128 which takes heated air from the clinker cooler 52 to the pre-calcination furnace 58 and is thus referred to a separate air pre-calcination furnace system 126. The SAS 82 aims to assist in overcoming the typical difficulties related to combustion. Generally, these include reducing the impact of lump fuel on the sulphate-based accumulation in the ascending gas ducts 34, facilitating the use of petcoke with alternative fuels such as tires or other fuel in pieces, reducing the level of CO and the temperature produced at the outlet of gas risers and calcinators when both conventional and alternative fuels are used, reducing NOx, via annealing and / or combustion in stages, reducing the ammonia slip in the NOx SNCR procedure and reducing the amount of trace or furan dioxins formed in an exhaust gas passage system (although not all benefits will necessarily be present at the same time). As a form of examples, some of the benefits may be an increase in the use of more alternative (or less refined) fuels and / or an increase in the use of alternative fuels at the same time as petroleum coke. The use of SAS 82 is also intended to contribute to the benefits. resulting in the substitution of more coal or oil for petcoke, the reduction of CO emissions with the use of alternative fuels and the reduction of NOx emissions. The benefits mentioned above can be achieved at the same time as achieving the goals of a higher clinker production index and the increased depletion of the fuel traces that come with raw materials. The installation of a furnace SAS 120, with an appropriate moment, angle of cyclonic baffles 100, body size with crushed wide front or flared diffuser so that a significant portion of the gas flow for processes is drawn into the vortex flow, before start a new piston-type expenditure zone in the rotary kiln 42 approximately at the end of the zone of Calcination (gas temperature> 1200 ° C), is expected to encourage the combustion of an unburned fuel in the process gas flow. Furnace SAS 120 is expected to facilitate combustion in the process gas flow by making the CO concentration more uniform within the portion of the furnace system to which it is added. In addition, the furnace SAS 120 should facilitate removing by rubbing the CO layer that forms on the hot powder in the inclined rotary kiln 42. By exposing the unburned fuel more frequently to a higher concentration of 02 and stirring the bed of load, the combustion must increase especially in the furnace system 20. (Although there may be practical limits as to how much recirculation of dust can be tolerated). Increasing the combustion in the gas flow for processes, should facilitate such thing as the use of lower levels of 02 in the upper end 46 of the rotary kiln 42 for the same level of substitution of conventional fuel for fuel in pieces. This in turn should result in less impact on the clinker production rate. In addition, it should facilitate the use of higher and / or less refined levels of lump fuel for the same level of 02 at the upper end 46 of the rotary kiln 42. The installation of an Oven SAS 120 also Expected to facilitate the use of petcoke with alternative fuels. The advantage of using SAS 82 is that the use of fuel in chunks with petcoke usually produces a more severe accumulation of sulfates, for the reasons described above, even at modest levels of petcoke use. Therefore, the installation of a SAS 82 in the furnace system at the end of the calcination zone should facilitate the use of higher levels of petcoke and / or a higher S grade of petcoke. The installation of a rising gas SAS 122 or SAS precalcining oven 124 is expected to reduce the CO output and the temperature level of ascending gas conduits 34 and precalcining furnaces 58 with the use of alternative fuel. Due to the higher rates of release of volatile materials from alternative fuels and the stratification of the 02 supply from the kiln and the exhaust gas passage system, which in turn leaves insufficient locally available 02 for the combustion of the materials volatile, in an excess of 02, to produce OH radicals to facilitate the combustion of CO; the introduction of fuel in pieces, only (in fact, this also happens with the coal pulverized in a certain measure) to the ascending gas pipes and the calcinadores can produce increases in CO and exit temperatures. This it leads to the need for higher levels of 02 in riser 34 or precalciner 58, leading to increases in fuel and reductions in the clinker production rate. Therefore, the installation of a SAS 82 in a pre-calcination furnace 58 that is designed for the appropriate time, the angle of the cyclonic baffle 100 and / or the size of the body with wide crushed forehead or the flared diffuser to mix as much as possible The flow of the rising gas pipe or the precalcining furnace in the high moment vortex flows before the center point of the pipe is expected to reduce the stratification and CO, the level 02 necessary to remove the CO and the exit temperatures. In turn, the addition of SAS 82 must also result in better combustion of coal, petcoke or fuel in pieces, improving fuel consumption and clinker production rate by increasing the calcination rate through the removal of the border layer of C02. The installation of a SAS 82 is also expected to reduce NOx, via annealing and splitting in stages. When introducing volatile matters into the gas flow for processes at approximately 1000-1400 ° C it must reduce the NOx via the annealing reaction, on the understanding that there is a deficiency of 02. The performance of the annealing depends on the temperature (the higher the best, 1200 ° C they are a good level) and local stoichiometry (preferably 0.85). In addition, the combustion stages, by allowing the volatile materials in the coal to burn stoichiometrically and reintroducing the rest of the air afterwards, reduce NOx formation from the oxidation of nitrogen in the fuel. Therefore, both the annealing and the stages can be used in the cement manufacturing process to reduce NOx levels and even produce kiln systems for "low NOx" cements. SAS 82 can make the strategy more effective as it can facilitate the combustion of lower quality coke after introduction into the final exhaust gas passage system if a precalcining oven SAS 124 is added to the kiln system . When a different furnace SAS 120 is added it will also increase the effectiveness of the strategy by ensuring that, if fuel is used in piece for annealing, it will burn before the end of the calcination zone. In addition, the use of Furnace SAS 120 to facilitate combustion of the fuel will also help to burn producing a more uniform concentration of 02 at the upper end of the furnace of 46. When installing a SAS 82 downstream in the process gas flow from the injection point of ammonia in a plant that operates the CNCR procedure of NOx, the small amount of unreacted or slipped ammonia can be converted to NO, hence avoiding dark plume formation and ammonia emission problems and allowing more ammonia to be added for a better degree of NOx reduction. In addition to all the above mentioned advantages, the installation of a SAS 82 is also expected to reduce the dioxins of an exhaust gas passage system. It is noted that the chunked fuel is fed into the feed rack of the furnace 38 or into the pre-calcining furnace 58, the resulting deficient depletion can lead to the formation of dioxins in the branches. This has also been observed when coal is used as fuel. The potential for dioxin formation is due to unburnt carbon or volatile materials that are transported to the discharge tube 80 of an exhaust gas passage system and act as excitators for a de novo synthesis reaction. Therefore, the installation of a SAS 82 in the initial part of the passage tube (similar to a calciner or gas riser) should facilitate the depletion of unburned material and eliminate the formation of dioxins. The installation of a SAS 82 can also increase the production of clinker in a furnace system 20. The general use of the SAS 82 range facilitates a lower level of 02 inside the oven system 20; processing lower gas outlet temperatures, better combustion and better heat transfer to the solid material. Thus, as an alternative to take advantage of all these advantages to their maximum extent (exploiting the higher levels of fossil fuel substitution by other fuels or petroleum coke or looking for lower levels of NOx), an increase in the production rate of Clinker can be obtained. In the previous text, although "fuel" has been discussed, it will be understood that combustible material, animal coal or volatile particles can also arrive with raw materials. The animal carbon can survive the passage through the preheater or the material with a fuel content with volatile particles can be fed to a lower stage of a preheater 20 or possible to the pre-calcining furnace 58 in order to reduce the episodes of distillation and emission to the air of volatile particles, which can happen if such material was added closer to the gas outlet of the preheater. In addition, although the above embodiments discuss the injection of air or gas, steam could, in principle, be injected in place of or in addition to air (although more time is required to achieve the same mixing effect), if it is conveniently available under pressure.

As will be understood, steam alone will not provide the same oxygen levels, however, this may not be important in situations where producing the effect of mixing may be the most important feature of SAS 82. It will also be understood that the invention does not is limited to the embodiments described herein that are merely illustrative of embodiments. preferred to carry out the invention, and which are susceptible to modification in form, arrangement of the parts, steps, details and order of the operation. The invention, rather, is intended to encompass all such modifications within its scope, as defined by the claims, including the application of furnace systems that produce products other than portland cement clinker. Furthermore, the invention is not limited to the use of a SAS 82 at only one point in a furnace system and there may be circumstances where a second SAS 82 (or more) system will add to the advantages and / or produce different benefits. EXAMPLE A SAS system as described above was successfully applied in an off-line calcining furnace system of 4500 tpd. The furnace was 84 m long and 5.2 m in diameter; the calciner had a volume of 350 m3 with a gas residence time of 2.5-3.0 seconds.

If in the SAS, even at high oxygen levels that cause a drop in the rate of production, the calciner had significant problems with CO, resulting in levels of up to 1500 ppm of CO to the unit set (which corresponds to 10,000 ppm). in the calciner at normal levels of 02 of 2-3%). The high level of CO was thought to come from the poor mix, hence the SAS was attempted as a solution to the problem. SAS was installed with a 10,000 Nm3 / hr fan that could supply a 2500 mm measure of water in order to solve generation problems due to poor mixing conditions. The system had 4 vortex flow injectors with 20 ° cyclonic deflectors that injected in a circle of 0.3R radius (R = radius of the calciner duct) and two vortex flow injectors directed towards a circle of 0.5R (in the same plane) in a reverse rotation manner, generally as illustrated in this text. An important wording on the CO level of about 2500 ppm was obtained in the calciner and around 500 ppm in the unit set, together with a drop in NOx concentration. The analysis of the carbon content in the hot powder fed to the kiln and the drop in CO indicated that a fuel saving of 1.5% was obtained. Hot dust analysis indicated a drop in LOI (loss on) of 2 indicating better decarbonization of the load percentage, which will allow an increase in the production of the oven. It was not possible to reduce the CO level to zero, due to the instability of the coal fed at the time of the measurements, since during some periods there was insufficient oxygen to burn the surplus coal delivered in a passing manner. It was also evident that there should not be any significant imbalance in the construction or performance of any injector (when there is more than one of them). The differences in manufacturing and the important differences in the distribution of the ducts that connect the fan can result in different performance of each injector.

Claims (25)

1. CLAIMS 1. A system for mixing a gas flow for processes that is flowing through a housing 92 of a furnace system 20, the system comprising: at least one injector (84, 86) equipped in said housing (94); a gas supply system (102) connected to at least one injector (84, 86) for supplying the injection gas to the injector (84, 86) at a predetermined pressure; and wherein the injector (84, 86) and the predetermined pressure are arranged and selected to inject the injection gas into the housing (92) at a sufficiently high moment to produce a jet having the appropriate turbulent flow characteristics so that the gas flow for processes is carried by the injected gas; and wherein the injector (84, 86) is equipped with vortex means to provide axial turbulence to the injected gas. A system according to claim 1, wherein the injector is positioned so that the gas flow flows through the housing (92) along an axis of the housing (92). 3. A system according to claim 1 or 2, in wherein the vortex means comprises cyclonic deflectors (100). 4. A system according to claim 3, wherein the cyclonic deflectors have an angle of about 10 to 35 degrees. 5. A system according to any of claims 1 to 4, wherein the injector is equipped with flared diffusers to increase the drag. 6. A system according to any of claims 1 to 4, wherein the injector is equipped with a body with a flattened wide front to increase drag. 7. A system according to. • any of claims 1 to 4, wherein the injector is equipped with a body with flattened wide front and flared diffusers to increase the drag. A system according to any of claims 5 or 7, wherein the flared diffusers are in mid-angles of about 5 to 20 degrees. A system according to any one of the preceding claims, wherein the gas flow for processes is dragged substantially before the flow of injected gas is converted into a piston-type expense together with the gas flow for processes or before the flow of gas. Injected gas impinges inside the housing. 10. A system according to any of claims 1 to 9, the system comprises: a plurality of injectors provided in the housing and placed at predetermined intervals around a cross section of the gas flow for processes and in communication with the interior of the housing; and a gas supply system for supplying injection gas to the injectors at a predetermined pressure; wherein the injectors are directed to inject the injection gas to incise tangentially in a circle centered on the axis of the process gas flow and cover at least about 5 to 15% of the cross-sectional area of the process gas flow. A system according to claim 10, wherein the plurality of injectors and the predetermined pressure are positioned and selected to inject the injection gas into the housing at a sufficiently high moment to produce a jet having the appropriate turbulent flow characteristics of so that the flow of gas for processes is carried away by the injected gas. A system according to claim 11, wherein the gas flow for processes is substantially entrained before the flow of injected gas is converted into a piston-type expense along with the gas flow for processes or before the gas flow is injected into the interior of the housing. A system according to any of claims 10 or 11, wherein the circle covers at least about 5% of the cross-sectional area of the housing. 14. A system according to any of claims 10 or 11, where the circle covers approximately 10% of the cross-sectional area of the housing. 15. A system according to any of claims 10 to 14, wherein the vortex means comprises cyclonic deflectors. 16. A system according to claim 15, wherein the cyclonic deflectors have an angle of about 10 to 35 degrees. 17. A system according to any of claims 10 to 16, wherein the injectors are equipped with flared diffusers. 18. A system according to any of claims 10 to 16, wherein the injectors are eguipated with bodies with crushed wide front. 19. A system according to any of claims 10 to 16, wherein the injectors are equipped with squashed wide front bodies and flared diffusers. 20. A system according to any of the claims 17 or 19, wherein the flared diffusers are in mid-angles of approximately 5 to 20 degrees. 21. A system according to any of claims 10 to 20, wherein the plurality of injectors is directed at an angle of approximately 0 to 60 degrees in the direction of gas flow for processes. 22. A system according to claim 21, wherein the plurality of injectors is directed at an angle of about 25 to 40 degrees in the direction of gas flow for processes. 23. A system according to any of claims 10 to 22, wherein the plurality of injectors (86) comprises a first set of injectors (86) and the system further comprises a second set of injectors (103) comprising: at least an injector (103) provided in the housing, placed in a second cross section of the housing (92) and in communication with the interior of the housing (92), and a second gas supply system for supplying injection gas to at least an injector (103) at a predetermined pressure, wherein at least one injector (103) is directed to inject gas to incise tangentially in a second circle (104) centered on the axis of the housing (92) having a different diameter than the circle (98) of the first set of injectors (86). 24. A system according to claim 23, wherein the second circle (104) has a larger diameter than the circle (88). 25. A system according to any of claims 23 or 24, wherein the second cross section of the housing (92) is separated from the cross section of the first group of injectors (86) in the gas flow direction for processes. 26 '. A system according to claim 23, wherein the gas supply system (102) for the first group of injectors further comprises the second gas supply system. 27. A system according to any of the preceding claims, wherein the gas injected is air or oxygenated air. 28. A system according to any of the preceding claims, wherein the injected gases can be preheated. 29. A system according to any one of the preceding claims, wherein the furnace system (20) serves to prepare hydraulic cement clinker and the system is in a region of the furnace system (20) where the temperature of the gas is approximately between 850 to 1400 degrees Celsius. 30. A system according to claim 29, wherein the gas temperature is between about 1000 to 1250 degrees Celsius. 31. A system according to any of the preceding claims, wherein the housing (92) is - a housing of a rotary oven (42). 32. A system according to claims 1 to 30, wherein the housing (92) is a housing of an exhaust gas passage system. 33. A system according to claims 1 to 30, wherein the housing (92) is a housing of a precalcining furnace. 34. A system according to any of claims 1 to 29, wherein the housing (92) is a housing of an ascending gas conduit (34). 35. A system according to any of claims 1 to 29, wherein the housing (92) is a housing of a precalcining furnace in a region near the gas outlet where the gas temperature is between approximately 900 a 1250 degrees Celsius. 36. A system according to any of claims 1 to 29, wherein the housing (92) is a housing of the furnace system (20) in a region where the system will improve the performance and the completion of the reactions with ammonia where the temperature of the gas is approximately between 850 to 1050 degrees Celsius. 37. A method for mixing the gas flow for processes of a furnace system comprising: supplying a source of high pressure injection gas; and injecting the injection gas into the gas flow for processes through at least one injection at a time sufficiently high to produce a jet having the appropriate characteristics of turbulent regime so that the gas flow for processes is entrained by medium of the injected gas; it also includes the imparting of turbulence to the injected gas as it enters the housing. 38. A method for mixing a gas flow for processes according to claim 37, wherein the turbulence is imparted by cyclonic deflectors provided to the at least one injector. 39. A method for mixing a gas flow for processes according to any of claims 37 to 38, wherein the entrainment is further improved through a flat-faced wide body provided with at least one injector. 40. A method for mixing a gas flow for processes according to any of claims 37 to 38, wherein the entrainment is further improved through a flared diffuser provided in the at least one injector. 41. A system according to any of claims 37 to 38, wherein the drag further increases through a flattened wide front body and a flared diffuser provided in the at least one injector. 42. A method for mixing a gas flow for processes according to any of claims 37 to 41, wherein the total moment of the gas injected during the injection is approximately 50 to 150% of the moment of gas flow for processes. 43. A method for mixing a gas flow for processes according to any of claims 37 to 42, wherein the injected gas is injected at or above approximately 150 meters / second. 44. A method for mixing a gas flow for processes in a housing of a furnace system comprising: supplying a high pressure injection gas source; and injecting the injection gas into the housing via at least one injection so that the injection gas impinges tangentially on a circle centered on the axis of the injection. gas flow for processes and covering at least approximately 5 to 15% of the cross sectional area of the process gas flow. 45. A method for mixing a gas flow for processes according to claim 44, wherein injecting the injection gas into the gas flow for processes is at a sufficiently high moment to produce a jet having appropriate characteristics of turbulent regime in a manner that the flow of gas for processes is carried away by the injected gas. 46. A method for mixing a gas flow for processes according to any one of claims 44-45, which further comprises imparting turbulence to the injection gas as it enters the housing. 47. A method for mixing a gas flow for processes according to claim 45, wherein the turbulence is imparted by cyclonic deflectors provided in the at least one injector. 48. A method for mixing a gas flow for processes according to any of claims 45 to 47, wherein the entrainment is further improved by means of a flat-faced wide body provided in the at least one injector. 49. A method for mixing a gas flow for processes according to any of claims 45 to 47, in where the drag is further improved through a flared diffuser provided with at least one injector. 50. A method for mixing a gas flow for processes according to any of claims 45 to 47, wherein the entrainment is further improved by means of a body with flattened wide front and a flared diffuser provided in the at least one injector. 51. A method for mixing a gas flow for processes according to any of claims 45 to 50, wherein the total moment of the injection gas during the injection is approximately 50 to 150% of the moment of the process gas flow. . 52. A method for mixing a gas flow for processes according to any of claims 44 to 51, wherein the injection gas is injected at or above approximately 150 meters / seconds. 53. A method for mixing a gas flow for processes of a furnace system according to claim 44, wherein the Reynolds number due to the mixture is about 2.5 times higher than that found in the gas flow for typical processes without mix. 54. A method for mixing a gas flow for processes of a furnace system according to claim 44, wherein the turbulent frequency due to the mixture is approximately 100 times greater than that found in the gas flow for typical processes without mixing. 55. A method for mixing a gas flow for processes of a furnace system according to claim 44, wherein a total moment, the turbulence and the vortex of the injected gas are selected based on the mathematical model in such a way that the injected gas will drag substantially all the gas flow for processes before the injected gas flow becomes a piston type expense along with the flow of gas for processes or before the injected gas flow hits the interior of the housing. 56. A method for mixing a gas flow for processes of a furnace system according to claim 44, wherein a total moment, the turbulence and the vortex of the injected gas are selected based on the mathematical model so that the The injected gas will substantially drag the entire process gas flow before the process gas flow is converted into a piston-type expense along with the process gas flow or before the flow of injected gas impinges into the interior of the housing. 57. A rotary kiln of an oven system provided with a system for mixing a process gas stream according to any one of claims 1 to 30. 58. A pre-calcining oven of an oven system provided with a system for mixing a flow Of gas for processes according to any of claims 1 to 30. 59. A system for passing exhaust gases from a furnace system provided with a system for mixing a gas flow for processes according to any of claims 1 to 30. 60. A preheater section of an oven system provided with a system for mixing a process gas stream according to any of claims 1 to 29. 61. An ascending gas conduit of an oven system provided with a system for mixing a flow of gas for processes according to any of claims 1 to 29.