mixes with the hot gases to provide an outlet gas stream 22 at the desired temperature the outlet gas stream is pulled i e sucker through the vaporizer 23 or another heat exchanger by a blower 24 the outlet gas stream leaving the blower at 24 a has been cooled by the heat exchanged the cooled outlet gas stream is exhausted at 25 to atmosphere other elements the same as those in fig1 bear the same numerals another direct waste heat recovery system is shown in fig3 that uses pipes with holes to suction the hot gas from the hot gas source 23 a metal header pipe 30 is attached 31 to the hot gas duct 80 pipes 27 with holes 28 facing the hot gas stream are inserted endwise into the metal header pipe 30 caps 29 are placed over projecting the ends of the pipes the fit of the pipes 27 into the metal header pipe and the fit of the caps 29 on the pipes can be a slip fit enabling thermal expansion of the pipes to occur and enabling the pipes to be constructed of a material different from the metal header pipe such as refractory or inconel alloy in the case of a vertical hot gas duct the pipes can seat or rest on top 31 a of the duct 80 or be inserted through holes in the ducting once again having a slip fit the outlet gas stream at 31 b is pulled through the vaporizer 31 c or another heat exchanger by the blower 31 d and exhausted to atmosphere at 31 e blower 31 d has its suction intake side connected to vaporizer chamber 90 other elements the same as in fig1 bear the.