Working principle of the circulating fumigation machine: the scientific logic from gas circulation to sterilization and insecticidal treatment

　　1.Core principle:Forced circulation and concentration gradient control

　　The core of the operation of the circulating fumigation machine lies in"breaking the natural diffusion constraints and establishing a controllable airflow circulation".The process can be divided into three stages:

　　1.Gas generation stage:Produce fumigation gas through a dosing device(such as an aluminum phosphide generator),or generate high-temperature steam through a heating system.

　　2.Circulation and diffusion stage:The fan compresses gas into the main pipeline and evenly distributes it into the treatment space(such as grain piles,warehouses)through branch pipelines.At the same time,a closed-loop circulation is formed through the return air inlet,ensuring that the gas concentration gradient is controlled within±5%.

　　3.Action stage:The gas comes into contact with pests and microorganisms,achieving a killing effect by inhibiting respiratory enzymes and disrupting cell structure.The circulating airflow ensures that the gas concentration in every corner reaches the lethal threshold.

　　II.Synergistic effect of key parameters

　　1.Temperature:Most fumigants(such as phosphine)exhibit high activity at 25-30℃.The equipment controls the ambient temperature within an optimal range through a heating system,and the temperature can be increased at low temperatures to enhance the effect.

　　2.Humidity:For grain fumigation,the humidity should be controlled between 65-75%.Too high a humidity can easily lead to mold growth in the grain,while too low a humidity can affect the volatilization of the fumigant.The equipment adjusts in real-time through a humidity sensor.

　　3.Concentration:Set the concentration according to the type of pest(for example,the lethal concentration of phosphine for Sitophilus zeamais is 0.3g/m³),and adjust the dosage through feedback from the gas sensor.

　　4.Time:Set the fumigation duration based on the concentration parameters(usually 72-120 hours)to ensure the complete eradication of insect eggs,larvae,and adults throughout their entire life cycle.