Experimental investigation of the increasing thermal efficiency of an indirect water bath heater by use of thermosyphon heat pipe

Abstract

Natural gas must be preheated prior to pressure reduction in city gate stations. Indirect water bath heaters are employed in city gate stations for preheating, consume a considerable amount of natural gas for the process. This type of heater has a low efficiency therefore a significant amount of energy is wasted. Due to the high capacity of thermosyphon heat pipe, its utilization in city gate stations heater were investigated experimentally in this paper. For this purpose, a heater set-up was manufactured and its thermal efficiency was calculated. The thermosyphon heat pipe were then designed, manufactured, and utilized between the fire tube and the gas tube. Further the type of working fluid and the range of filling ratio were discussed and the most effective state was suggested. Moreover, the thermal efficiency of the heater in the presence of thermosyphon heat pipe was investigated. The obtained results showed that the thermal efficiency of the heater improved up to 13% with the addition of thermosyphon heat pipe. The most effective state of thermosyphon heat pipe was associated with the water as working fluid with 20% filling ratio in the front route and methanol as working fluid with 30% filling ratio in the back route of the fire tube.