Bath heaters using alternative heat transfer medium: a thermo-economic analysis

In this paper, the performance enhancement of a particular type of heater, i.e., water bath heater, with a wide range of industrial applications is proposed and assessed. The idea is centered around using an alternative working fluid with better heat transfer characteristics (heat transfer oil—HTO) to quantify the impacts not only from a technical point of view but also from an economic perspective. The indirect heater of Arkan CGS (located in North Khorasan province of Iran) is selected as the case study, and its laboratory model is constructed by dimensional analysis. The thermal analysis is done at different fluid flow rates in the heating coil of the experimental setup. The results are verified by both numerical simulation and available empirical correlation. The results show that using HTO as the heating medium leads to heater efficiency improvement by up to 158%, and it will also lead to energy savings of up to 36.5%. A comprehensive economic analysis is carried out based on the technical results. It is found that the internal rate of return and dynamic payback period are in the ranges of 42–67% and 1.53–2.17 years, respectively.