Underground LNG storage tank heat tracing system and method

The invention relates to a buried LNG storage tank heat tracing system and method.The system comprises a tank bottom fluid heat tracing system, the tank bottom fluid heat tracing system comprises a temperature collecting module, a pressure collecting module, a flow collecting module, a heat tracing module and a working medium pump module, and the temperature collecting module and the heat tracing module are installed in a bearing platform of an LNG storage tank; the pressure acquisition module and the flow acquisition module are both mounted at a total inlet and a total outlet through which fluid enters the heat tracing module, and the working medium pump is mounted at the total inlet of the heat tracing module and provides pressure for heat exchange of the fluid; the tank wall electric heat tracing system comprises a temperature acquisition module and an electric heat tracing module, and the temperature acquisition module and the electric heat tracing module are laid in the concrete outer tank wall of the LN