HEAT EXCHANGE BLOCK FOR REGENERATIVE BURNER

 Modern regenerative burners for heating and thermal furnaces  have rather larger sizes and small heat exchange period time that is  connected with a low thermal capacity of the refractory materials  applied to production of a nozzle. Considerable decrease in the sizes  of nozzle and increase in heat exchange period time can be reached  by using the hidden warmth of metals melting, which can be placed  in the closed thin-walled reservoirs. In addition, the paper propose  section design and a heat exchange unit enable to solve the problem  of reducing the size of regenerative unit and increase the time of the  swap, compared to existing regenerators that are used for air heating  in regenerative burners. The proposed design can be used to create  regenerative burners, a new class of highly effective, high temperature air preheating, and considerable time of swap. Such reservoirs,  in which temperature of metal melting is equal, are packed in the sections. The next sections’ melting temperature differs approximately by 100  °C. It allows to maintain the fixed section temperature, which  is equal the temperature of metal melting in this section, and removing from its surface or giving it, by products of combustion, warmth,  which sets out in case of crystallization or is absorbed when metal  kernel melts. Calculation of the swap time and the metal mass in one  section, based on the joint solution of equations of heat balance and  heat transfer between the heated air and the surface of tanks, allows  to determine the overall dimensions of each section, filled with melting or crystallizing metal and its heat exchange surface. Fusible kernel mass, sizes of section and heat exchange period time calculations  for regenerative block consisting of ten sections with a fusible kernel  is given in this work. Calculation proves a possibility of decrease in  dimensions of a regenerative nozzle for a 200 kW burner, and increase in heat exchange period time, while air heating temperature  remains constant. The technical solution can be used in a thin-walled  container in which are placed the metals with different heat of fusion. Large size regenerative burners hamper their use in heating and  thermal furnaces, and fast parecidos leads to a decrease in period of  operation of the changeover valve.

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