GB1382084A - Heating of liquids - Google Patents

Abstract

1382084 Fluent fuel fired liquid heater; liquid heaters HUTNI DRUHOVYROBA 22 March 1972 [2 April 1971 9 Nov 1971] 13319/72 Headings F4B and F4A Liquid is heated by the combustion of a fuel/air mixture in a radiant bed. Gaseous, or vaporized liquid, fuel mixed with air is fed at a rate exceeding the flame propagation speed and a temperature below the ignition temperature to a bed 13, Fig. 3, of material surrounded by a water jacket 6. The cross-section of the bed is such that the temperature is the same throughout any cross-section, and the bed particles are cool between levels A-A- and B-B, complete combustion occurs between levels B-B and C-C, the bed materials emitting, radiation of wavelengths mainly between 0À5- 6 Ám, i.e. infra-red. The upper part of the bed cools the combustion gases to the desired flue temperature at level D-D. The gases may pass to the chimney through an outer jacket 11, and the wall of the combustion space may be finned. Several combustion spacers 24 in a single water jacket may be fed from a mixer 29, Fig. 4, and the system may operate with induced draught. The distribution of the fuel/air mixture may be obtained by nozzles or slots, or through a grate 25, Fig. 4. The cool bottom part of the bed prevents back-firing and protects the grate or nozzles, and the height of the bed is such that excessive flue temperatures are avoided. The bed particles may be zirconium silicate, oxides of thorium, zirconium or chromium, carbides of boron or silicon or metal such as tungsten or tantalum or other material stable at the operating temperature of about 1600‹ C. The size of the grains is chosen in accordance with the size of the combustion chamber and the required temperature distribution. The active bed material may be formed as a coating on a carrier.