Marine methanol engine starting preheating device

The invention relates to a preheating device for starting of a marine methanol engine, and belongs to the technical field of preheating equipment for cold starting of methanol engines. The marine methanol engine starting preheating device comprises a feeding pipe system, a heat exchanger is arranged on the feeding pipe system, the heat exchanger is communicated with a liquid storage mechanism, and the liquid storage mechanism is connected with an exhaust pipe of a marine methanol engine; a heat supply pipe system is arranged between the liquid storage mechanism and the heat exchanger, a heat absorption pipe system is arranged between the liquid storage mechanism and the exhaust pipe, and a first bypass pipe system is arranged on the heat absorption pipe system. The waste heat of the exhaust pipe of the engine is used for preheating methanol fuel during cold start, and when the marine methanol engine stops running, hot water in the heat absorption pipe system is introduced into the liquid storage mechanism, so