Patent Publication Number: US-2015075071-A1

Title: Biofuel Gasification Reactor

Description:
FIELD 
     This invention relates to the field of alternative energy sources. More particularly, this invention relates to a biofuel gasification reactor. 
     INTRODUCTION 
     Facilities in remote areas often require electricity, either for the convenience and comfort of the facility personnel, or to run some of the equipment installed at the facility. Various methods are used to provide this electricity, including installing lengthy runs of power transmission lines, solar cells, batteries, and generators that run on a variety of different petroleum products. 
     Unfortunately, each of these power sources tends to suffer from a variety of different limitations or problems. For example, installing power lines can provide an adequate supply of electricity at relatively low on-going costs, but tends to have enormous up-front costs—costs that cannot be justified if the run is too lengthy, or the facility will not be operational long enough. Solar cells and batteries tend to only provide a limited amount of energy. Gasoline, diesel fuel, or other petroleum distillates must typically be trucked-in to the facility site to supply a generator, which complicates the supply logistics for the facility, and can also be quite expensive. 
     What is needed, therefore, is a system that reduces problems such as those described above, at least in part. 
     SUMMARY 
     The above and other needs are met by a biofuel gasification reactor for producing effluent gases that are combustible in an internal combustion engine. The reactor includes an elongate vessel disposed in an upright orientation. A biofuel loading port is at the top of the vessel, has a cover, and is sized to receive biofuel of at least about eight inches in diameter and twenty inches in length. A biofuel storage zone is disposed below the loading port, and stores and provides the biofuel to lower zones within the reactor via gravity feed only. 
     A plasma zone is below the storage zone, and oxidizes the biofuel into char and precursor gases containing at least carbon dioxide and water vapor. The plasma zone has a tapered configuration that is wider at the top and narrower at the bottom. Air nozzles are radially disposed through a circumference of the vessel at the plasma zone for providing air to the plasma zone. A helical air preheater is disposed outside the vessel and wrapped around the circumference of the vessel at the plasma zone for receiving air from an ambient environment and providing the air to the nozzles. A reduction zone is below the plasma zone for receiving the precursor gases and char from the plasma zone, having a diameter that is less than the diameter of the vessel. 
     A char zone is below the reduction zone and receives the precursor gases and char from the reduction zone. The char zone has a tapered configuration that is wider at the bottom and narrower at the top. The precursor gases are substantially converted to effluent gases of hydrogen and carbon monoxide within at least one of the reduction zone and the char zone. 
     A grating is below the char zone and holds the char until it is oxidized to ash, then permitting the ash to fall through. The grating is disposed in a substantially fixed and immovable configuration during the operation of the reactor. The grating passes substantially all of the effluent gases to an ash cone that is beneath and partially surrounds the vessel, and receives the ash through the grating. An effluent gas outlet port in the ash cone above the bottom of the vessel provides the effluent gases to an internal combustion engine. 
     In various embodiments, the plasma zone, reduction zone, and char zone are all formed of refractory brick inside the reactor vessel. In some embodiments the reactor vessel is formed of steel. In some embodiments the grating is formed of steel. In some embodiments the reduction zone has a diameter of about 27 inches. In some embodiments the vessel has a diameter of about 108 inches. In some embodiments the vessel has a length of about 200 inches. In some embodiments the plasma zone and the reduction zone each have a height of about 28 inches. In some embodiments the grating is about 24 inches square. In some embodiments the preheater makes about three complete revolutions around the vessel. 
     According to another aspect of the invention there is described a biofuel gasification system that includes the reactor described above, which produces effluent gases. A cyclone receives the effluent gases from the reactor, and dries, cools, and purifies the effluent gases at least in part. A selectively by-passable blower draws the effluent gases from the cyclone during a startup phase of the system. A condenser selectively receives the effluent gases from the blower during at least a portion of the startup phase of the system, and dries, cools, and purifies the effluent gases at least in part. A first flare receives the effluent gases from the condenser and indicates the presence of the effluent gases by igniting them. A cooling tower selectively receives the effluent gases from the blower during at least a portion of the startup phase of the system, and selectively receives the effluent gases from the cyclone during an operational phase of the system, and dries, cools, and purifies the effluent gases at least in part. A filter receives the effluent gases from the cooling tower, and dries, cools, and purifies the effluent gases at least in part. A second flare selectively receives the effluent gases from the filter during at least a portion of the startup phase of the system, and indicates the presence of the effluent gases by igniting them. An output selectively receives the effluent gases from the filter during the operational phase of the system. 
     According to various embodiments according to this aspect of the invention, an internal combustion engine receives the effluent gases from the output, and burns the effluent gases to produce motive power. Some embodiments include first and second separate filters, where the first filter receives the effluent gases from the cooling tower, and the second filter receives the effluent gases from the first filter. 
     According to another aspect of the invention there is described a method for producing effluent gases that are combustible in an internal combustion engine, by receiving biofuel through a loading port at the top of an elongate vessel, where the loading port sized to receive biofuel of at least about eight inches in diameter and twenty inches in length. Dropping the biofuel through a storage zone disposed in the vessel below the loading port, the storage zone providing the biofuel to lower zones within the reactor only via gravity feed. Oxidizing the biofuel into char and precursor gases containing at least carbon dioxide and water vapor in a plasma zone disposed in the vessel below the storage zone, the plasma zone having a tapered configuration that is wider at the top and narrower at the bottom. Providing air to the plasma zone with air nozzles that are radially disposed through a circumference of the vessel at the plasma zone. Receiving the air from an ambient environment and providing the air to the nozzles through a helical air preheater disposed outside the vessel and wrapped around the circumference of the vessel at the plasma zone. Restricting passage of the biofuel through the plasma zone with a reduction zone that is disposed in the vessel below the plasma zone and has a smaller diameter than the plasma zone. Receiving the precursor gases and char from the reduction zone with a char zone disposed in the vessel below the reduction zone, the char zone having a tapered configuration that is wider at the bottom and narrower at the top. Substantially converting the precursor gases to effluent gases comprising hydrogen and carbon monoxide within at least one of the reduction zone and the char zone. Holding the char from the char zone with a grating until the char is oxidized to ash and then permitting the ash to fall through the grating. Retaining the grating in a substantially fixed and immovable configuration during operation. Passing substantially all of the effluent gases through the grating, and then providing the effluent gases to an outlet. 
     In various embodiments according to this aspect of the invention, the effluent gases are filtered to reduce particulate content. In some embodiments the effluent gases are cooled. In some embodiments the effluent gases are dried. In some embodiments the effluent gases are burned in an internal combustion engine. In some embodiments the effluent gases are used to power an electrical generator. 
    
    
     
       DRAWINGS 
       Further advantages of the invention are apparent by reference to the detailed description when considered in conjunction with the figures, which are not to scale so as to more clearly show the details, wherein like reference numbers indicate like elements throughout the several views, and wherein: 
         FIG. 1  is a functional block diagram of a biofuel gasification reactor system according to an embodiment of the present invention. 
         FIG. 2A  is a representation of a first phase of construction of a biofuel gasification reactor according to an embodiment of the present invention. 
         FIG. 2B  is a representation of a second phase of construction of a biofuel gasification reactor according to an embodiment of the present invention. 
         FIG. 2C  is a representation of a third phase of construction of a biofuel gasification reactor according to an embodiment of the present invention. 
         FIG. 2D  is a representation of a fourth phase of construction of a biofuel gasification reactor according to an embodiment of the present invention. 
         FIG. 2E  is a representation of a fifth phase of construction of a biofuel gasification reactor according to an embodiment of the present invention. 
         FIG. 2F  is a representation of a sixth phase of construction of a biofuel gasification reactor according to an embodiment of the present invention. 
         FIG. 3  is a top plan view of a grating for a biofuel gasification reactor according to an embodiment of the present invention. 
         FIG. 4  is a perspective view of a top hatch for a biofuel gasification reactor according to an embodiment of the present invention. 
     
    
    
     DESCRIPTION 
     System Overview 
     With reference now to  FIG. 1 , there is depicted a functional block diagram of a biofuel gasification reactor system  100  according to an embodiment of the present invention. The biofuel, such as wood, is loaded into the reactor  102  and oxidized to produce carbon dioxide and water. The carbon dioxide and water are then reduced in an oxygen deprived region to form hydrogen and carbon monoxide, generally referred to as gases herein. 
     In some embodiments the gases pass from the reactor  102  to a cyclone  104 , in which the gases are, to some extent, cooled, dried, and cleaned. In some embodiments the gases enter the cyclone  104  through a six inch pipe at a bottom peripheral position of the cyclone  104 , and exit through a top central position of the cyclone  104 . In one embodiment the cyclone  104  is a metal tank that is about eight feet tall and about three feet in diameter. In some embodiments a valve at the bottom of the cyclone  104  allows collected water that condenses out of the gases to be drained off. 
     In some embodiments the gases are at least initially drawn out of the reactor  102  and through the cyclone  104  by a blower  106 . In some embodiments, the blower  106  is only used at the start of the reaction process, while later in the process other forces, such as pressures within the reactor  102  or vacuums formed by the operation of later pieces of equipment as described more fully hereafter, provide all of the motive force required to move the gases through the system  100 . In some embodiments the blower  106  selectively passes the gases to at least one of a cooling tower  112  and a condenser  108 . 
     The condenser  108  is used to further cool, dry, and clean the gases. In one embodiment the condenser  108  is a metal cylinder about six feet tall and about four feet in diameter. In some embodiments the gases are introduced into the condenser  108  through a six inch pipe that enters the tank  108  at a position about half way up the length of the sidewall of the tank, and the gases exit the condenser  108  from a central position at the top of the condenser  108 . A valve is provided at the bottom of the condenser  108  in some embodiments, so as to drain off the water that condenses out of the gases that flow through the condenser  108 . 
     In some embodiments the condenser  108  provides the gases through a six inch pipe to a first flare  110 . The first flare  110  is used, for example, to determine when the reactor  102  is producing combustible gases. At a point in time when the reactor  102  is producing combustible gases, a valve between the blower  106  and the condenser  108  is closed and a valve to the cooling tower  112  is opened, so that the gases are not wasted by just flaring some portion of them off with the first flare  110 . This diverts all or a selectable amount of the gases to the cooling tower  112 . 
     In some embodiments the cooling tower  112  is used to further cool, dry, and clean the gases. In one embodiment the cooling tower  112  is a metal cylinder about sixteen feet tall and about three feet in diameter. In some embodiments the gases are introduced into the cooling tower  112  through a six inch pipe that enters the cooling tower  112  at a position about four feet up the length of the sidewall of the cooling tower  112 , and the gases exit the cooling tower  112  from a central position at the top of the cooling tower  112 . A valve is provided at the bottom of the cooling tower  112  in some embodiments, so as to drain off the water that condenses out of the gases that flow through the cooling tower  112 . 
     In some embodiments the gases that leave the cooling tower  112  are provided to a filter  114 , such as through a six inch metal pipe, which filter  114  is used to further cool, dry, and clean the gases. In one embodiment the filter is a rectangular metal box that is about four feet tall, four feet wide, and two feet deep. In some embodiments the gases enter one side of the filter  114  at a position that is about three feet up the sidewall of the filter  114 , and exit the filter  114  at a similar position on the opposing side of the filter  114 . Inside the filter  114 , the gases pass through a first set of one or more particulate filters, such as spun fiberglass filters. In some embodiments the gases then pass through a second set of electrostatic filters before exiting the filter  114 , such as through a six inch metal pipe. In some embodiments a condensate drain area is provided at the bottom of the filter  114  and a valve is provided at the bottom of the filter  114 , so as to drain off the water that condenses out of the gases that flow through the filter  114 . In some embodiments more than one filter  114  is used. In some embodiments two filters  114  are placed in series, and in some embodiments two filters  114  are placed in parallel. 
     The gases output from the filter  114  are selectively provided, such as through a six inch pipe, to at least one of a second flare  116  and an engine  118 . In one embodiment, the gases are initially fed to the second flare  116 , so that it can be determined that combustible gases are being provided to that point in the operation of the system  100 . In some embodiments, once the presence of gases at the second flare  116  has been determined, the second flare  116  is isolated from the flow of gas, and the gases are provided exclusively to the engine  118 , so that the gases are not wasted by just flaring some portion of them off with the second flare  116 . 
     The gases that arrive at the engine  118  are used to power the engine  118 . The engine  118  in some embodiments is a spark-type engine, such as an internal combustion engine. The motive power produced by the engine  118  can be used for a variety of purposes. For example, the engine  118  can be used to turn a generator and generate electricity. Alternately, the engine  118  can be used to drive machines such as a pump, winch, or hoist. 
     The benefit of the system  100  as described is that the system  100  uses a variety of biofuels that can be more easily and economically either found in the vicinity or brought to the location of the facility that is serviced by the system  100 . 
     Reactor 
     One embodiment of the construction of the reactor  102  is now described, with reference to  FIGS. 2A-2F . It is appreciated that other dimensions and constructions are contemplated within the scope of the present invention. Unless otherwise described herein, the components of the reactor  102  are all formed of a durable material, such as steel. However, not all of the components need to be formed of the same material, or even of the same kind of steel. Instead, the material for each component can be selected as desired to fit the environment, purpose, and use of each component, as described herein. It is also appreciated that the various elements of the reactor  102  can be joined together in a variety of different way, even though welding might be specified at various places herein. 
     With reference now to  FIG. 2A , a reactor vessel  200  is formed by fabricating a tube with a radius of about 54 inches and a length of about 200 inches. As depicted in  FIG. 1 , the right end of the vessel  200  will be disposed in a downward position when the reactor  102  is operational, and is therefore commonly referred to herein as the bottom of the vessel  200 . Also as depicted in  FIG. 1 , the left end of the vessel  200  will be disposed in an upward position when the reactor  102  is operational, and is therefore commonly referred to herein as the top of the vessel  200 . 
     An ignition port  244  is formed through the sidewall of the vessel  200 , at a position that is a bit higher than about 62 inches from the bottom end of the vessel  200 . The ignition port  244  has a diameter of about 4 inches. A cover that can be selectably opened and closed is fabricated for the ignition port  244 . 
     A series of about 15 equally-spaced holes are drilled through the sidewall of the vessel  200 , and an air injection nozzle  204  is welded on the inside of each hole, with each air injection nozzle  204  disposed in a radial orientation. The air injection nozzles  204  have a diameter of about 1.5 inches and a length of about 6 inches. They are disposed at a position of about 44 inches up from the bottom of the vessel  200 . A base ring  202  is welded on the inner diameter of the vessel  200 . The base ring has a radial width of about 4 inches. 
     With reference now to  FIG. 2B , a cone ring  208  is welded to the vessel  200  at a position that is about 28 inches from the end of the vessel  200 . The cone ring  208  has a radial width of about 10 inches. About four grating brackets  210  are welded to the underside of the cone ring  208 , equally disposed around the circumference of the cone ring  208 , and having a length that is substantially similar to the radial width of the cone ring  208 , which in this embodiment is about 10 inches. 
     A bullet-shaped ash cone  206  is welded onto the cone ring  208 . The cylindrical portion of the ash cone  206  has a radius of about 74 inches and a length of about 48 inches, at which point the ash cone  206  has a hemispherical shape with a radius of about 74 inches. A gas exhaust port  248  is formed in the ash cone  206 , at a position that is about half-way along the portion of the vessel  200  that extends into the ash cone  206 . The gas exhaust port  248  has a diameter of about 6 inches. Additional support structure can be added, as desired, to hold the ash cone  206  to the vessel  200 . 
     With reference now to  FIG. 2C , a reduction ring  212  is attached to the inside of the vessel  200  at a position that is about 31 inches up from the bottom of the vessel  200 . The reduction ring  212  has a radial width of about 13.5 inches. An ash removal port  218  is formed in the bottom end of the ash cone  206 , with a diameter of about 20 inches. A cover that can be selectably opened and closed is fabricated for the ash removal port  218 . 
     A section formed of refractory brick that is mortared smooth extends above and below the reduction ring  212  to a distance of about 31 inches in each direction from the reduction ring  212 . The refractory brick section includes a plasma zone  214  and a char zone  216 , with a reduction zone  246  disposed between the two at the reduction ring  212 . The thickness of the refractory brick is about 4 inches at the tapered ends and about 13.5 inches at the tapered center portion. Thus, the reduction zone  246  has a diameter of about 27 inches. The air injection nozzles  204  are positioned to extend just into the plasma zone  214 , at a position along the length of the vessel  200  where the refractory brick is about 6 inches thick. Both the reduction ring  212  and the base ring  202  help to support the weight of the refractory brick when the reactor  102  is in its upright position. 
     In one embodiment the refractory brick of the plasma zone  214 , reduction zone  246 , and char zone  216  forms an hour-glass cross section. In other words, the inner walls of the plasma zone  214  have a somewhat paraboloid cross-sectional shape to them, as do the inner walls of the char zone  216 , which are substantially mirror-image of one another at the reduction ring  212 . This particular shape provides great benefits in staging the fuel through the plasma zone  214 , reduction zone  246 , and char zone  216  in such a way that it is appropriately oxidized and the precursor gases are efficiently and substantially converted into effluent gases. 
     With reference now to  FIG. 2D , a grating  222  is placed over the bottom end of the vessel  200 , and is held in place by supports  220 , such as chains suspended from the grating brackets  210 . The grating  222  is sized so as to completely cover the bottom end of the vessel  200 , but fit within the inner diameter of the ash cone  206 . The center of the grating  222  can be supported, such as by a length of about 1.5 inch wide angle bracket extending completely across the grating  222 . 
     In some embodiments the grating  22  is formed in sections so as to fit into the reactor  102  through the service port  224 . For example, the grating  222  can be formed of three sections that are sized so that they can fit through the service port  224  to be installed or removed, and then can be assembled inside of the ash cone  206  and hung on the grating chains  220  so that the grating  222  is held in its proper position beneath the char zone  216  at the bottom of the vessel  200 . In one embodiment the grating  222  is held fixed and immovable during operation of the reactor  102 . 
     More detail for the grating  222  is provided in  FIG. 3 . The grating  222  has grating pegs  234 , to which the grating supports  220  are attached. The bars  236  of the grating  222  are rounded, so that char that decomposes on top of them can fall more easily through the grating  222  as it reduces in size. The bars  236  in one embodiment are formed of about 0.75 inch diameter solid stainless steel rods set at a spacing of about 0.75 inches. The spacing between the bars  236  is selected so as to retain char above a desired size within the char zone  216 , and to allow char below a desired size to drop into the ash cone  206 , from whence it can eventually be removed through the ash removal port  218 . 
     One problem with the design of some gasification reactors is that they cannot use large biofuels, such as the logs described above, and the gratings must be agitated so as to not become clogged with ash. Putting large biofuels into such reactors tends to increase the clogging problems with the grating. By selecting characteristics such as those described above in regard to the grating  222 , the reactor  102  as described herein is able to accommodate large biofuel sizes, and yet operate without clogging the grating  222 , even without any means by which the grating  222  is agitated or shaken to clear it. It is noted that this is a valuable benefit of the present system  100  as described, because the size of the reactor  102  would make it very difficult to shake it, and the inclusion of an agitator for the grating  222  would create additional complexity and expense. 
     With reference now to  FIG. 2E , a service port  224  is formed in the side of the ash cone  206 , with a position where the top of the service port  224  (when the reactor  102  is disposed in its upright position) is about the same level as the bottom of the vessel  200 , where the grating  222  is disposed. The service port  224  has dimensions of about 32 inches square. A cover that can be selectably opened and closed is fabricated for the service port  224 . 
     An annular preheater  226  is placed around the vessel  200  just above the ash cone  206 . The annular preheater  226  receives ambient air through an air inlet port  228 , circulates it around the vessel  200 , such as in about three helical passes around the circumference of the vessel  200 , and provides it to the plasma zone  214  through the air injection nozzles  204 . During the operation of the reactor  102 , the annular preheater  226  heats the air that is provided for the gasification of the biofuel within the reactor  102 . In some embodiments, the air inlet port  228  has a diameter of about 6 inches, and the circumferential passes of the annular preheater  226  have cross-sectional dimensions of about 8 inches square. In some embodiments a blower is connected to the air inlet port  228 , so as to force air into the reactor  102 . 
     With reference now to  FIG. 2F , the reactor  102  is depicted in its operational orientation. Legs  230 , or some other means, are attached so as to keep the reactor  102  upright. In some embodiments, the legs  230  are formed of about 6 inch diameter steel pipe, with a length of about 222 inches. Support plates with a thickness of about 0.3.75 inches can be secured near the top of the legs  230 , and platform feet with a size of about 24 inches square and about 2 inches thick can be secured at the bottom of the legs  230 . A personnel platform  232  with safety railings and an access ladder are provided at the top of the reactor  102 . 
       FIG. 4  provides detail in regard to the top port  242 , through which the biofuel is loaded into the reactor  102 . Top port has dimensions of about 24 inches square, and is covered with a door  240  that is about 27 inches square and about 0.375 inches thick. The door  240  slides on roller bearings along rails  238 , such as about 1.5 inch diameter tubes. The rails  238  and door  240  are formed such that when the door  240  is in position above the top port  242 , a relatively tight seal is formed. 
     Operation 
     In one method of operation, the reactor  102  is loaded through the top loading port  242  to the top of the vessel  200  with biofuel. In one embodiment the biofuel is wood, such as logs or split logs that are about four inches to about eight inches in diameter, and from about sixteen inches to about twenty inches in length. In other embodiments, wood briquettes or pucks are used as the biofuel. In other embodiments, animal waste or vegetation is used. The biofuel need not be dried, but in general, drier fuel presents a better reaction effluent. Once the reactor  102  is loaded, the door  240  on the top of the reactor  102  is closed by sliding it along the rails  238 . 
     During the startup phase of operation, the blower  106  is started, the valves to the first flare  110  and the second flare  116  are open, and the valves to the cooling tower  112  and the engine  118  are closed. An ignition source is used to ignite the biofuel within the reactor  102 . In one embodiment, a rag is soaked with about one quart of diesel fuel, lit, and tossed into the reactor  102  through the ignition port  244 , which is then closed. The draw from the blower  106  sucks air in through the air inlet port  228 , the annular preheater assembly  226 , and the air injector ports  204 , pulling the flaming rag into and igniting the biofuel in the reduction zone  246 . 
     The startup phase lasts approximately six hours, after which combustible gases are produced in sufficient quantity by the reactor  102 . During the startup phase, the biofuel is gasified in a plasma ball that forms in the plasma zone  214 . If the vessel  200  has a diameter that is substantially bigger than that as described herein, then the plasma in the plasma zone  214  tends to form a ring instead of a ball, and the gasification of the biofuel is less efficient. If the vessel  200  has a diameter that is substantially smaller than that as described herein, then the reactor  102  is not able to receive biofuel of the large size as described herein. The temperature within the plasma zone  214  reaches approximately two thousand degrees Fahrenheit, depending upon the biofuel that is used and the amount of oxygen that is present. 
     The restricted diameter of the reduction zone  246  tends to prevent the biofuel from falling down past the plasma zone  214  until it is partially converted to a char, at which point it falls through the reduction zone  246  and into the char zone  216 , where it is stopped by the grating  222 , and the charring process continues. The temperature in the char zone  216  is not as high as the temperature in the plasma zone  214 . The gases are drawn down through the reactor  102  into the ash cone  206  and out through the gas outlet port  248 . 
     The first flare  110  can be configured so that a flame ignites automatically when volatile gases are present there or, alternately, the output at the first flare  110  can be repeatedly manually checked for volatility. At the end of the startup period, the first flare  110  will ignite, indicating that the gases are ready to move through the rest of the system  100 . 
     At the end of the startup period, when volatile gases are detected at the first flare  110 , the valves to the first flare  110  are closed, the flame at the first flare  110  is extinguished, and the valves to the cooling tower  112  are opened. When the second flare  116  lights, the gas has made its way to that point in the system  100 . Similar to that as described above in regard to the first flare  110 , the second flare  116  can be configured so that a flame ignites automatically when volatile gases are present there or, alternately, the output at the second flare  116  can be repeatedly manually checked for volatility. 
     At this point, the valves to the second flare  116  are closed, the flame at the second flare  116  is extinguished, the valves to the engine  118  are opened, and the engine  118  is started, using the gas as its fuel. In some embodiments about a 1:1 ratio of gases to air is used as the intake mix for the engine  118 . Once the engine  118  is running, the valves around the blower  106  can be selectively adjusted to by-pass the blower  106 , which can then be shut down, as the draw from the intake from the engine  118  is sufficient to provide all the suction that is necessary to draw the gases through the system  100 . 
     The reactor  102  can be opened at the top port  242  during processing, to replace biofuel that has fallen by gravity through the reactor  102  as it has been converted first to char and then to ash in the process. In some embodiments it is preferred to reseal the door  240  on the port  242  once the biofuel reloading process is completed. This can be done again and again as the biofuel is spent, such that the output of gases from the system  100  is substantially continuous. In other words, it is not necessary to stop production of the gases to open the top port  242  and refuel the reactor  102 . The biofuel can be provided to the top of the reactor  102  such as with a conveyor belt or other means. 
     While it is best to start with a relatively dry biofuel in some embodiments, the various components of the system  100  tend to reduce the amount of water in the gases to an acceptable level. For example, in some embodiments the gases delivered to the engine  118  have a relative humidity that is no more than about 20 percent, and are filtered for particulates that are no greater than about 20 microns. Further, the gases are cooled through the system  100  from an initial exit temperature from the reactor  102  of about 600 degrees Fahrenheit to a delivery temperature at the engine  118  of about 80 degrees Fahrenheit. A reactor  102  of the size as described herein can produce about 15,000 cubic feet per minute of volatile gases. However, the engine  118  might only consume about 3,000 cubic feet per minute of the gases. Thus, the system  100  in some embodiments is capable of supplying as many as about 5 engines simultaneously, or alternately, could be scaled to drive the desired number of engines  118 , or to merely store the gases produced. 
     The foregoing description of embodiments for this invention has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the invention to the precise form disclosed. Obvious modifications or variations are possible in light of the above teachings. The embodiments are chosen and described in an effort to provide illustrations of the principles of the invention and its practical application, and to thereby enable one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when interpreted in accordance with the breadth to which they are fairly, legally, and equitably entitled. 
     REFERENCES 
     
         
           100  Biofuel Gasification Reactor System 
           102  Reactor 
           104  Cyclone 
           106  Blower 
           108  Condenser 
           110  First Flare 
           112  Cooling Tower 
           114  Filter 
           116  Second Flare 
           118  Engine 
           200  Vessel 
           202  Base Ring 
           204  Air Injection Nozzles 
           206  Ash Cone 
           208  Cone Ring 
           210  Grating Brackets 
           212  Reduction Ring 
           214  Plasma Zone 
           216  Char Zone 
           218  Ash Removal Port 
           220  Grating Chains 
           222  Grating 
           224  Service Port 
           226  Annular Preheater 
           228  Air Inlet Port 
           230  Reactor Legs 
           232  Reactor Platform 
           234  Grating Pegs 
           236  Grating Bars 
           238  Top Port Rails 
           240  Top Port Door 
           242  Top Port 
           244  Ignition Port 
           246  Reduction Zone 
           248  Gas Exhaust Port