摘要 |
<p>A waste heat boiler for cooling a hot process stream comprising within a cylindrical shell a plurality of heat exchanging tubes (2) having an inlet end and outlet end; an outlet chamber (18) for withdrawing the cooled process stream; attached to the shell, means for introducing water (10) on shell side of the tubes; means for introducing the hot process stream (16) into the inlet end of the tubes and passing the process stream through the tubes (2) in indirect heat exchange with the water on shellside of the tubes to produce steam and to cool the introduced process stream; means for withdrawing produced steam (8), and means for withdrawing the cooled gas stream, which waste heat boiler being further equipped with an insulated by-pass tube (4) having an outlet end in the boiler outlet chamber (18), the outlet chamber (18) being provided with an injection nozzle (20) for control of flow of the hot process stream through the by-pass tube (4) by injection of a fluid into the by-pass tube outlet end. <MATH></p> |