Abstract: Based on the double compressor semi-open heat pump drying system, the experimental test bench was established, and the semi-open heat pump drying system used for tobacco drying was analyzed. The experimental results showed as follows: (1) During the whole tobacco curing process, the average performance coefficient of the integrated heat pump system was 2.90, the maximum instantaneous performance coefficient of the integrated system was 3.26, and the SMER was 2.42 kg/(kW•h), showing high energy efficiency. (2) Compared with coal-fired flue-cured tobacco, the average SMER of the semi-open heat pump drying system is 3 times higher than that of coal-fired flue-cured tobacco, and the cost of drying 1 kg of dried tobacco leaves is saved by 28.6%, with significant energy saving advantages and economic benefits.

Key words: Semi-open heat pump drying, Tobacco curing, Coefficient of performance, SMER