Abstract:
A burner reformer is provided for a power generating system using fuel cell. A burner is contained inside the reformer. The reformer absorbs heat from the burner and other heat source to reduce heat loss and save connecting wires. The present invention avoids flashing back of hydrogen. When fuel is lean, flame would not easily die and the system can thus work stably.

Description:
TECHNICAL FIELD OF THE INVENTION 
     The present invention relates to a reformer; more particularly, relates to providing a burner reformer used in a power generating system using fuel cell. 
     DESCRIPTION OF THE RELATED ARTS 
     Oil consuming brings in problems of environmental contamination and resource wasting, which also leads to green-house effect. Hence, new energy technologies are developed. Wind power is limited to local environment, tide power is the same, geothermal energy has no difference, and solar cell has problem in low conversion rate. Yet, fuel cell has low pollution rate, small noise, high efficiency and wide application. Hence, it has become one of the key energy technologies to be developed. Fuel cell does not burn a traditional fuel to generate heat, but convert chemical energy into electric energy to generate heat, which usually consumes hydrogen as a fuel. 
     Since hydrogen usually does not exist alone in nature, hydrogen generating system becomes one of the critical issues. Methane, methanol, ethanol, gas, liquefied petroleum gas, oil, etc. can be sources for generating hydrogen through reformation. A reformer can be used to reform a fuel selected from the above sources into a hydrogen-rich gas in a high-temperature environment. The reformer needs different type of heat according to its own type. For improving system efficiency, residual fuel obtained after electrochemical reaction in a burner is usually recycled for combustion to improve heat in a high-temperature tail-gas for processing reformation in the reformer. 
     However, the reformer is usually operated above 800 Celsius degrees (° C.) and the burner is set aside from the reformer, so that the burner has to connect to the reformer through tubes or pipes. But, the high temperature is hard to be kept. For solving the problem, the burner is sometimes operated under 1000° C., which raises operational risk. 
     In the U.S. Pat. No. 7,156,886 B2 patent, a burner is integrated with a reformer. But, it only stacks the burner and the reformer. The burner is position under the reformer to provide tail gas after combustion to the reformer for reformation. Yet, heat loss is still great. In US 2010/0136378 A1 patent, the burner avoids flashing back of hydrogen. Yet, when the fuel is lean, flame may die and the whole system may be thus stopped. Hence, the prior arts do not fulfill all users&#39; requests on actual use. 
     SUMMARY OF THE INVENTION 
     The main purpose of the present invention is to provide a burner reformer having a simple structure to be easily operated with improved efficiency, reduced contamination and lowered cost. 
     The second purpose of the present invention is to not only avoid flashing back of hydrogen but also help system run stably to keep from flaming out even when fuel is lean. 
     To achieve the above purposes, the present invention is a burner reformer for a fuel cell power generating system, comprising a gas inlet, a residual fuel inlet, an oxidant inlet, a spraying device, a porous media burner, a fuel inlet, a pre-heater, a distributing ring, a spreading plate, a plurality of fuel reformers, an igniter, a first tail-gas outlet, a plurality of tail-gas deflectors, a guiding channel, a guiding blade, a second tail-gas outlet, a plurality of outlets of burner reformer and an reformate gas outlet, where a hydrogen-rich gas generated from the burner reformer is directly provided for electrochemical reaction in solid oxide fuel cell (SOFC) or, for electrochemical reaction with proton exchange membrane (PEM) to generate electric energy coordinated with removing carbon monoxide and cooling down temperature. Accordingly, a novel burner reformer for a fuel cell power generating system is obtained. 
    
    
     
       BRIEF DESCRIPTIONS OF THE DRAWINGS 
       The present invention will be better understood from the following detailed description of the preferred embodiment according to the present invention, taken in conjunction with the accompanying drawings, in which 
         FIG. 1  is the sectional view showing the preferred embodiment according to the present invention; 
         FIG. 2  is the view showing the spraying device; 
         FIG. 3  is the view showing the distributing ring; 
         FIG. 4  is the view showing the state of use of the present invention. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The following description of the preferred embodiment is provided to understand the features and the structures of the present invention. 
     Please refer to  FIG. 1  to  FIG. 4 , which are a sectional view showing a preferred embodiment according to the present invention; a view showing a spraying device; a view showing a distributing ring; and a view showing a state of use of the present invention. As shown in the figures, the present invention is a burner reformer for a fuel cell power generating system, comprising a gas inlet  101 , a residual fuel inlet  1011 , an oxidant inlet  102 , a spraying device  103 , a porous media burner  104 , a first tail-gas outlet  105 , a plurality of tail-gas deflectors  106 , a guiding channel  107 , a guiding blade  108 , a second tail-gas outlet  109 , an igniter  201 , a fuel inlet  301 , a pre-heater  302 , a distributing ring  303 , a spreading plate  304 , a plurality of fuel reformer  305 , a plurality of outlets of burner reformer  306  and a reformate gas outlet  307 . 
     The gas inlet  101  guides a gas to enter. 
     The residual fuel inlet  1011  is connected with the gas inlet  101  to guide an unreacted residual hydrogen-rich gas to enter. 
     The oxidant inlet  102  guides an oxidant to enter for providing an oxygen-contained gas or fuel. Therein, the oxidant is a high-temperature oxygen-contained gas at cathode outlet of a cell stack; a general normal- or high-temperature gas; or a cooled-down gas from the cathode outlet of the cell stack. 
     The spraying device  103 , as shown in  FIG. 2 , is positioned in a combustion chamber  100  and is connected with the gas inlet  101  and the residual fuel inlet  1011 . The spraying device  103  comprises a fuel tube  1031 ; a plurality of branch tube  1032 ; and a spraying hole  1033  located on each branch tube  1032 . The spraying device  103  guides the gas or fuel to enter from the fuel tube  1031  to be directly sprayed from the spraying hole  1033 . The gas or fuel is sprayed in the porous media burner  104  to process a burning reaction with gas entered from the oxidant inlet  102 . 
     The porous media burner  104  is located on the spraying device  103  in the combustion chamber  100  to burn the fuel entered from the spraying device  103 , which is mixed with the oxidant entered from the oxidant inlet  102 . 
     The first tail-gas outlet  105  is connected at an upper terminal of the combustion chamber  100  to output a high-temperature tail-gas obtained after combustion. 
     The tail-gas deflector  106  surrounds the first tail-gas outlet  105  and the combustion chamber  100  at outside to guide the high-temperature tail-gas entered from the first tail-gas outlet  105  for providing heat to process reformation with a catalyst in the fuel reformer  305 . 
     The guiding channel  107  penetrates through a loading plate  3051  to pass the high-temperature tail-gas from the loading plate  3051  to the spreading plate  304  without contacting the distributing ring  303 . 
     The guiding blade  108  surrounds the combustion chamber  100  and is located on a lower surface of the distributing ring  303 . The guiding blade  108  is an area for processing pre-heating to the high-temperature tail-gas entered from the guiding channel  107 . 
     The second tail-gas outlet  109  outputs the high-temperature tail-gas to be collected. 
     The igniter  201  is located on the porous media burner  104  to obtain energy for activating the burner reformer  305  to process burning in the porous media burner  104 . 
     The fuel inlet  301  guides a to-be-reformed fuel to enter, where the to-be-reformed fuel comprises gas, air and water and is changeable according to fuel formula and reforming method. 
     The pre-heater  302  surrounds the combustion chamber  100  at outside to absorb heat of a high-temperature tail-gas to pre-heat fuel. 
     The distributing ring  303 , as shown in  FIG. 3 , surrounds the combustion chamber  100  at outside and is located above the pre-heater  302 . The distributing ring  303  has a plurality of fuel distributing holes  3031  to uniformly spray the pre-heated fuel by the fuel distributing holes  3031 . Thus, the fuel is uniformly sprayed to enter the spreading plate  304  for reformation in the fuel reformer  305 . 
     The spreading plate  304  surrounds the combustion chamber  100  at outside and is located on the distributing ring  303 . The spreading plate  304  has a plurality of spreading holes  3041  to uniformly spread the sprayed fuel by the spreading holes  3041 , where the distributing ring  303  and the spreading plate  304  are combined to form a distribution spreading area. 
     The fuel reformer  305  surrounds the combustion chamber  100  and is located on the spreading plate  304  to be loaded on the loading plate  305  for reformation to generate hydrogen-rich gas. 
     Each of the outlets of burner reformer  306  is located on the fuel reformer  305  to output a reformed hydrogen-rich gas. 
     The reformate gas outlet  307  is located on the outlets of burner reformer  306  to guide the hydrogen-rich gas to a cell stack to generate electric energy through electrochemical reaction. 
     On using the present invention for generating hydrogen, gas entered from the spraying device  103  and air entered from the oxidant inlet  102  are mixed in the porous media burner  104  for burning through activating the burner reformer  306  by the igniter  201 . The high-temperature tail-gas obtained after combustion enters into the tail-gas deflector  106  through the first tail-gas outlet  105  for reformation with a catalyst in the fuel reformer  305 . Then, through the guiding channel  107 , the high-temperature tail-gas penetrates through the spreading plate  304  and the distributing ring  303  of the distribution spreading area. Then, the high-temperature tail-gas enters the guiding blade  108  to provide heat to pre-heat fuel. At last, the high-temperature tail-gas is output to a heat exchanger  401  through the second tail-gas outlet  109  (as shown in  FIG. 4 ) to absorb extra heat for fully using the heat in combustion. For reformation, the fuel flows into the pre-heater  302  from the fuel inlet  301  to absorb heat from the high-temperature tail-gas for pre-heating. Then, the fuel enters into the distributing ring  303  to be sprayed by the distributing ring  303 . Then, after being uniformly spread through the spreading plate  304 , the fuel enters into the fuel reformer  305  for reformation to generate hydrogen-rich gas. At last, the reformate gas enters into the cell stack  501  from the reformate gas outlet  307  for generating electric energy through electrochemical reaction. Un-reacted residual hydrogen-rich gas is guided to the anode residual fuel outlet  1011  to enter the burner reformer  100  for combustion through the spraying device  103 . At the same time, the gas entered from the gas inlet  101  can be reduced to none gradually until the whole system is stably run without inletting any gas. 
     As shown in  FIG. 4 , the hydrogen-rich gas thus generated is directly provided for electrochemical reaction in solid oxide fuel cell (SOFC) to generate electric energy; or, for electrochemical reaction with proton exchange membrane, (PEM) to generate electric energy coordinated with removing carbon monoxide and cooling down temperature. Then, the residual fuel obtained after the electrochemical reaction is guided to the spraying device  103  of the burner reformer  100  for recycling to improve system efficiency and reduce environmental contamination. Thus, the present invention has a simple structure and is easily operated with improved efficiency, reduced contamination and lowered cost. Furthermore, the temperature distribution in area of the combustion is very uniform for high practicality, whose gradient is within 30 Celsius degrees (° C.). 
     Concerning characteristics of the present invention, a burner is contained inside of a reformer; heat of a high-temperature generated after combustion in the burner is absorbed; and, conductive and radiating heat of the burner is absorbed. Thus, surface temperature is reduced and no pipes are required for connecting the reformer and the burner. Heat loss is reduced and operational temperature of the burner is lowered as well to diminish operational risk. The burner used in the present invention is a non-premixed porous media burner, which not only avoids flashing back of hydrogen but also helps system run stably to keep from flaming out even when fuel is lean. 
     To sum up, the present invention is a burner reformer for a fuel cell power generating system, where the present invention has a simple structure and is easily operated with improved efficiency, reduced contamination and lowered cost. 
     The preferred embodiment herein disclosed is not intended to unnecessarily limit the scope of the invention. Therefore, simple modifications or variations belonging to the equivalent of the scope of the claims and the instructions disclosed herein for a patent are all within the scope of the present invention.