Optimization Design of Phosphine Absorption System and Air Conditioning System in Warehouse for Tobacco Aging

In order to save capital investment in construction of warehouse for tobacco aging and rationalize the arrangement of auxiliary facilities, the purification system for exhaust gas after phosphine fumigation and air conditioning system were optimized with HVAC (heating, ventilating and air conditioning) technology. The ventilation pipe was designed in accordance with centralized double duct air conditioning system, comprising of phosphine purification equipment and modular air conditioning units, and PLC was adopted to automatically adjust the temperature and humidity in the warehouse and monitor the phosphine concentration in exhausted air during fumigation. The results of practical application showed that optimal design shortened the duration of phosphine purification and realized the zero emission of harmful gas. Tobacco leaf aging could be conducted at different layers or areas in warehouse, and the emission of phosphine gas after fumigation was safe and reached the standard. The air conditioners were installed in a separate room, and the warehouse space was increased relatively, which saved 5310 thousand RMB yuan per warehouse building. The operation of air conditioning units could be controlled according to the amount of aged leaves, which reduced the consumption of electric power and the cost of leaf aging.