Abstract:
A method and apparatus for eliminating noxious products in the emissions of hydrocarbon combustions exhaust gases includes the combination of three forms of radiant energy production which all together and/or also separately concur to eliminate all the carbon particulates and the unburnt hydrocarbons, as well as the volatile gases (SOV) deriving from combustion processes of any kind. The three forms of radiant energy are: radiant energy by means of radiant tubes; radiant energy produced by bombarding the material by means of microwaves due to a quantum effect; and radiant energy created by pulsed laser rays properly sent upon a graybody.

Description:
PRIORITY CLAIM 
       [0001]    This application claims priority to PCT Application No. PCT/IT2005/000173 filed Mar. 30, 2005, which is incorporated herein by reference. 
     
    
     TECHNICAL FIELD 
       [0002]    Embodiments of the invention relate to innovative technologies for eliminating the noxious emissions produced by hydrocarbon burning. 
       BACKGROUND 
       [0003]    The state of art shows various techniques to raise the temperature of the burning hydrocarbons aftergases in order to reduce, by post-combustion or catalysation processes, the quantity of noxious residues in the emissions of hydrocarbons combustion. 
         [0004]    These techniques are represented, for example, by the apparatus FAP (filter anti particulate) produced by some car makers, consisting of a device which raises for a few moments at a temperature of about 400° C. the fumes in order to better eliminate the noxious emissions. By post-combustors boosted by gas flame are already applied at industrial level on big plants of electric energy production and plants for waste disposal. 
         [0005]    Nevertheless all the existing systems present in some way various faults which make their application unsatisfactory. For instance a too low exercise temperature, a too high energy consumption, the possibility of creating further pollutant gases by the same post-burning process and in any case the impossibility of dramatically reducing the carbon particles and the unburnt hydrocarbons which today represent the most noxious component of the emissions. The ineffectiveness of these solutions is demonstrated today by the clear fact that no unique and general system exists that is able to satisfy people&#39;s demands due to an increased sensibility and intolerance to the atmospheric pollution which produces a highly negative environmental impact. 
       SUMMARY 
       [0006]    Embodiments of the present invention are directed to the total elimination of noxious pollutants in the emissions produced by hydrocarbons combustion by means of the innovative association of three ways of producing radiant energy whose destructive power is used against carbon particles, unburnt hydrocarbons and all the volatile noxious gases (SOV). 
         [0007]    The three forms of radiant energy are the following:
   1. radiant energy by means of radiant tubes   2. radiant energy produced by bombing the material by microwaves due to a quantum effect; and   3. radiant energy created by laser pulsed rays properly directed on a graybody.   
 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
         [0011]      FIG. 1  is a graph showing two inverse temperature profiles and the lambda zone of a material. 
           [0012]      FIG. 2  is a cross-sectional view of a linear radiant reactor according to one embodiment of the present invention. 
           [0013]      FIG. 3  is a cross-sectional view of U-tube reactor according to one embodiment of the present invention. 
           [0014]      FIGS. 4 and 5  are diagrams of double U-tube reactors according to embodiments of the present invention. 
           [0015]      FIGS. 6 and 7  show W- or M-shaped reactors according to embodiments of the present invention. 
           [0016]      FIG. 8  illustrates a double-spiral reactor according to one embodiment of the present invention. 
           [0017]      FIG. 9  illustrates a reactor including multiple tubes according to one embodiment of the present invention. 
           [0018]      FIG. 10  illustrates a spiral reactor in a spherical container according to one embodiment of the present invention. 
           [0019]      FIG. 11  illustrates a Moebious ring reactor according to one embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION  
       [0020]    The association between heat created using gas burners or electric resistance elements and heat created by microwaves has been used for cooking ceramics. 
         [0021]    In fact, since ceramic is a bad conductor of heat, the transfer of heat created by gas or electric burners on ceramic&#39;s surface was not very effective in order to reach uniformly the center of the same ceramic material. On the contrary for its nature the heat transfer obtained by microwaves inside the material rectified this shortcoming. Nevertheless, microwaves by themselves do not heat perfectly since the surfaces lose heat and get cold. All this brings to two inverse temperature profiles which join very well ( FIG. 1 ). 
         [0022]    In a similar way also resistances applied to the radiant tubes cannot maintain a constant temperature because the smokes flux tends to collect and remove the heat from the system. 
         [0023]    The aim of embodiments of the present invention is to combine the traditional gas or electric radiant energy with a simultaneous volumetric energy due to microwaves in the same reactor. 
         [0024]    A further innovation is the use of pulsed low or medium power laser able to hit deep layers of the fluid and contemporarily to maintain a very high and constant temperature of the radiant reactor (curve C— FIG. 1 ). 
         [0025]    This complex three-way-energy system enhances over four times the capacity of destroying pollutants in comparison with the traditional means and allows a high energy savings of more than 50%, improving the system quality which offers a remarkable rationality and clean practice. 
         [0026]    Embodiments of the present invention include a high-temperature post-combustion process which utilizes three different phenomenon of combustion: 1) the first one based on the radiant capacity of radiant tubes faces (or combustion chamber of the reactor); 2) the second one based on the destruction of PM by microwaves; and 3) the third one characterized by heat transfer through pulsed laser on the surface of the reactor&#39;s combustion chamber of the complex of gases and materials (PM, unburnt hydrocarbons, SOV, NOx) while passing inside the reactor. 
         [0027]    Heat transfer and the related temperatures produced by the radiant energy systems of the radiant tubes and radiant energy by microwaves have different and opposite diagrams in function of the penetration into the material on which the heat transfer is made, as it is shown in  FIG. 1 . 
         [0028]    In fact if we examine a particle of particulates of a size around 5 micron, the heat transfer with successive potential destruction by radiant tube radiation is the highest on the particle&#39;s external surface and lowers proportionally up to zero in the particle&#39;s core. There is a “k” absorption coefficient linked to the nature of the material, to its structure and dimension, to the starting temperature, and to the temperature of the material itself. 
         [0029]    In fact it is wellknown from the state-of-the-art that particulates are reduced from micron to nanometric dimensions. At these dimensions the microwaves energy begins immediately to function and acts positively destroying the particulate&#39;s core and so eliminating also that of nanometric dimensions. 
         [0030]    The use of radiant energy with radiant tubes for eliminating the noxious pollutants of diesel and petrol engines and more generally speaking of all the engines working with hydrocarbons and/or composite hydrocarbons has been dealt in the patent PCT/EP03/51113, which is incorporated herein by reference. The radiant energy following the curve A of  FIG. 1  will be more efficient on the outer part of the pollutant particle. 
         [0031]    The microwaves source may be a vacuum cavity where an antenna calibrated for the purpose will send electromagnetic waves able to produce in a shielded closed space a temperature in a range between 500° C. and 1400° C. according to the requirements of the system to which it will be applied. In point LAMBDA, triple point of meeting of the three phases of heat transferring ( FIG. 1 ), a synergy will be created between the heat generated by the radiant energy originated by radiant tubes and the heat produced by microwaves. Microwaves acting in the material&#39;s depth, as shown in curve B of  FIG. 1 , will be able to destroy the pollutant particle&#39;s core while the radiant energy will act on the outer part of the same. 
         [0032]    The frequency range of microwaves in embodiments of the present invention is set forth below: 
         [0000]    
       
         
               
               
               
               
             
           
               
                   
               
             
             
               
                 from 300 Mhz 
                 from 1 m 
                 from 10 −6   
                 microwaves UHF 
               
               
                 to 3 Ghz 
                 to 100 mm 
                 to 10 −5   
               
               
                 from 3 Ghz 
                 from 100 mm 
                 from 10 −5   
                 microwaves SHF 
               
               
                 to 30 Ghz 
                 to 10 mm 
                 to 10 −4   
               
               
                 from 30 Ghz 
                 from 10 mm 
                 from 10 −4   
                 microwaves EHF 
               
               
                 to 300 Ghz 
                 to 1 mm 
                 to 10 −3   
               
               
                   
               
             
          
         
       
     
         [0033]    By using microwaves, the thermal gradient within the stack of fired goods as well as within the product itself can be lowered, especially if used in conjunction with radiant energy (gas firing or radiant electric heating elements) from outside. 
         [0034]    Firing time can be reduced up to a quarter compared to regular radiant firing techniques. 
         [0035]    Energy cost can be reduced by up to 50 percent. 
         [0036]    Microstructure and crystalline phases can be influenced to modify specific properties, i.e. forming more uniform grain sizes throughout the ceramic body. 
         [0037]    Lower fluorine emissions in the brick industry, as well as lower hydrocarbon emissions are possible based on shorter soak times. 
         [0038]    Pores incorporated in the green (unfired) ceramic body will remain open longer during the firing process and allow the body to sinter to maximum density. 
         [0039]    The use of a pulsed laser in order to trigger a radiant reactor for eliminating the noxious pollutants of diesel and petrol engines and more generally speaking of all the engines working with hydrocarbons and/or composite hydrocarbons has been dealt with in the patent PCT/EP03/51115, which is incorporated herein by reference. 
         [0040]    The technologies of radiant energy in embodiments of the present invention for eliminating the noxious pollutants existing in the exhaust gases of auto and/or Diesel cycle internal combustion engines, are applied to a reactor in different forms, as already described in patents PCT/EP03/51113 and PCT/EP03/51115, which are incorporated herein by reference. The forms of the radiant reactor can be: linear tube ( FIG. 2 ), “U” tube ( FIG. 3 ), “double U” tube ( FIGS. 4 and 5 ), “W” or “M” tube ( FIGS. 6 and 7 ), “double spiral” ( FIG. 8 ), multiple tubes with the recycle of exhaust gases ( FIG. 9 ), and “spiral” ( FIG. 10 ) included in a spherical container in which the base of maneuvering and controlling of this sphere will be a GPS program based on an inertia ellipsoid. 
         [0041]    In the embodiments of  FIGS. 2-11  the operation is as follows. The exhaust gases coming from the internal combustion engines are routed inside the radiant reactor are hit by one, two or all the three described systems of radiation: 
         [0042]    radiant energy generated by 1 or more electric resistances; 
         [0043]    radiant energy generated by microwaves; and/or 
         [0044]    radiant energy generated by pulsed laser 
         [0045]    One embodiment of the invention includes materials resistent to high temperatures (range 600° C.-1400° C.). Moreover, some embodiments include a waterproof case perfectly free of parasitic and/or galvanic currents, of heat injections and of humidity and insulated with proper materials and thickness in relation with the demands of any applications, and with a depression produced by a soft and/or strong vacuum pump. 
         [0046]    The system as combined may be applied as a KIT on the collector of any Otto or Diesel engine. The system may be supplied with a control exchange with by-pass at high temperature or at smoke alarm or in presence of any other irregular working. 
         [0047]    The high temperatures field reachable by processes of transfer of heat without flame, and by that definable under the name of radiant processes and microwaves processes, is a sector in very rapid expansion and, as already outlined, it is possible to find interesting points in the already existing applications, but simply in specified sectors of any single technology and not related to their interconnection for a well defined aim which in our case is the elimination of any kind of pollutant included into the exhaust gases from the combustion of cycle Otto or cycle Diesel engines fuelled by hydrocarbons of various kinds and anyway derived from fossil material. 
         [0048]    Embodiments of the invention may also be applied to the combustion of public and private land carriers which burn fossil fuel, as well as river crafts, internal sea and ocean marine carriers, to heating plants either for single units or for big housing estates, in addition to all heating plants of public buildings, and big power plants for the production of electricity from fossil fuel. 
         [0049]    A further application for embodiments of the invention is aviation, where the almost quadratic rising in the flights number per year is producing pollution either on the soil level in low atmosphere or in high atmosphere with heavier and heavier effects in time. 
         [0050]    Referring to  FIG. 2 , a linear reactor includes an external case ( 201 ) where is set the pulsed laser heating system ( 202 ), by an inner box ( 211 ) where are the cavities of microwaves ( 212 ) and the radiant body ( 221 ) made by a simple linear tube heated by radiant energy supplied by one or more electric resistances ( 222 ) and passed through by the exhaust gases ( 231 ). 
         [0051]      FIG. 3  illustrates a U-tube reactor including an external case ( 301 ) where is set a pulsed laser heating system ( 302 ), by an inner box ( 311 ) where are cavities of the microwaves ( 312 ) and a radiant body ( 321 ) in “U” form, heated by radiant energy supplied by one or more electric resistances ( 322 ) and passed through by exhaust gases ( 331 ). 
         [0052]      FIGS. 4 and 5  are diagrams of double U-tube reactors which, instead of the electric resistances put as spirals on the radiant tubes, utilizes panels ( 401 ) with one or more electric resistances ( 402 ) in which the radiant body ( 403 ) in “U” shape is passed through by the exhaust gases ( 404 ).  FIG. 5  illustrates a radiant body ( 501 ) in “double U” form heated by radiant energy supplied by one or more electric resistances ( 502 ) and passed through by the exhaust gases ( 503 ). 
         [0053]      FIGS. 6 and 7  show W- or M-shaped reactors, with the reactor of  FIG. 6  including an external case ( 601 ) where is located the pulsed laser heating system ( 602 ), by an inner box ( 611 ) where are the microwaves cavities ( 612 ) and the radiant body ( 621 ) in “W” or “M” form heated by radiant energy supplied by one or more electric resistances ( 622 ) and passed through by the exhaust gases ( 631 ).  FIG. 7  shows a reactor which, alternatively to the electric resistances, put as spirals on the radiant tubes, utilizes panels ( 701 ) with one or more electric resistances ( 702 ) where the radiant body ( 703 ) in “U” or “M” shape, is passed through by the exhaust gases ( 704 ). 
         [0054]      FIG. 8  illustrates a double-spiral reactor including an external case ( 801 ), by an inner box ( 811 ) where are located the microwaves cavities ( 812 ) and the radiant body ( 821 ) in a “double toroid” shape heated by radiant energy supplied by one or more electric resistances ( 802 ) and passed through by the exhaust gases ( 831 ). 
         [0055]      FIG. 9  illustrates a multiple-tube reactor including a shell ( 901 ) in which is located the heating system by means of electric resistances, by one or more microwave s cavities ( 912 ) and the radiant body ( 921 ), made up by a multiple composition of radiant tubes laid-out in order to allow the exhaust gases recycle, is heated by radiant energy supplied by one or more electric resistances ( 922 ) and passed through by the exhaust gases ( 931 ). 
         [0056]      FIG. 10  illustrates a spiral reactor including an external case ( 1001 ) in spheric form where is located the heat transfer system by pulsed laser ( 1002 ) fixed and/or rotating around the external body, by an inner box ( 1011 ) where are the microwaves cavities ( 1012 ) and the radiant body ( 1021 ) in “volute” form where the exhaust gases ( 1031 ) are contemporarily or in order pushed and bombarded by pulsed laser ( 1002 ) and by microwaves ( 1012 ). 
         [0057]      FIG. 11  illustrates a Moebious ring reactor including a radiant body ( 1101 ) having a Moebious ring form and is passed through by the exhaust gases ( 1102 ) which are bombarded contemporarily or in order by the pulsed laser and by the microwaves. 
         [0058]    From the foregoing it will be appreciated that, although specific embodiments of the invention have been described herein for purposes of illustration, various modifications may be made without deviating from the spirit and scope of the invention.