LNG regasifi cation technology in natural gas applications mostly involves vaporizers heating liquefi ed natural gas and 

converting it into gaseous natural gas. Accurate evaluation of heat transfer characteristics is of great value for the optimal 

design of advanced regasifi cation devices such as submerged combustion vaporizer (SCV) and intermediate fl uid vaporizer 

(IFV). It is observed that the submerged combustion vaporizer (SCV) system has the problems of high energy demand 

and high operating cost. In contrast, the intermediate fl uid vaporizer (IFV) system has lower energy consumption and cost, 

but is greatly aff ected by environmental factors. Considering the advantages and disadvantages of these two methods, this 

paper proposes a hybrid operation method combining IFV and SCV to reduce the energy consumption and operation cost 

of LNG regasifi cation. In addition, the process simulation model is established by HYSYS software, and combined with 

genetic algorithm, some operating parameters are optimized by using unit energy consumption, unit cost and total natural 

gas output as objective functions. The results show that the combination of IFV and SCV can signifi cantly reduce energy 

consumption and cost compared with the use of SCV alone. This study provides a new idea for understanding the LNG 

regasifi cation system and provides a reference for the effi cient operation of SCV and IFV.