Objective With the aim of improving the efficiency of vacuum distillation furnaces, Feyzin refinery decided to preheat the combustion air by the waste gases going to the stack. Rather than using a proven solution with a conventional heat exchanger (static or rotating), ELF FRANCE chose to test a heat pipe exchanger disigned and manufactured in France. This demonstration was European "first".Inlet air temperature : same as ambiant airPreheater air temperature : 354 deg.Temperature of waste gases at heater outlet : 400 deg.Temperature of stack : 160 deg.Increase in heater efficiency : 14 %Energy saving : 2 200 toe/year- The furnace has a power capacity of 15,400 th/h. It is of the vertical cylindical type. a) UPSTREAM EXCHANGER : this exchanger (classical type) receives flue-gas from the furnace (400 deg. ) which is then lowered to a temperature of 330 deg. by exchange with the combustion air. b) HEAT-PIPE EXCHANGER : flue gas from the upstream exchanger (330 deg. ) passes across the heat-pipe exchanger and emerges at 160 deg. The rated heat transfer output is 1300 KW.Characteristics : . finned heat-pipes : length 5 m - OD 44,5 mm - t 2,6 mm thickness. number of heat-pipes : 345 (15 rows of 23 pipes). materials : TU 42 C steel. contained fluid : toluenec) EXTRACTOR FAN : to overcome pressure drops within this exchanger assembly, a blowing fan and an extractor are installed in the air and flue gas circuits respectively. Programme(s) ENG-ENALT 2C - Programme (EEC) of demonstration projects relating to the exploitation of alternative energy sources and to energy saving and the substitution of hydrocarbons, 1983-1985 Topic(s) 3.4 - ENERGY INDUSTRY Call for proposal Data not available Funding Scheme DEM - Demonstration contracts Coordinator Elf Aquitaine Production EU contribution No data Address 26 avenue des Lilas 64018 Pau France See on map Total cost No data