Study On Themonitoring Of Phosphine Fumigation Environment Exhaust Gas Dissipates

Fumigationexhaust gas is in an airtight fumigation treatment of residual fumigant chemical gas, fumigation exhaust gas containing high concentrations of toxic gases.If it was discharged directly into the atmosphere, the potential threats to human health and ecological environment will be occurred.To inquiry phosphine fumigation and degassing process in the phosphine of diffusion and dissipated law and the effect factors, security, efficient, reasonable and effective control storage grain pest, different dosing and administration dosage hydrogen phosphide gas release rates and spatial diffusion and grain in the warehouse of Sinograin Huizhou deport in 2014~2016.Inthe tall warehouse,aluminium phosphide of different dosing way and dosing dose phosphine gas release rate and in warehouse within space and grain heap in the of diffusion situation, and phosphine on to control of red flourbeetleTribolium castaneum(Herbst)and rusty grainbeetleCryptolestes ferrugineus(Stephens), insecticidal effect, dissipating in the process of suffocating exhaust gas is studied, the main results are as follows:56% purity of aluminum phosphide tablets based on 5 g/m3 standard was used for routine fumigation in large warehouse number 01 by artificial feeding aluminum phosphide tablets and fumigation on bulk grain surface, sealed off the warehouse and started monitoring changes in the concentration of Phosphine.After 48 h space and air duct the internal concentrations of phosphine gas insecticidal concentrations after 300 m L/m3,72 h provided all the concentration of phosphine gas detection points are basically the same. Warehouse space in 6 d peak concentration, peak grain Interior 7 d, phosphine gas reaching more than 300 mL/m3 of 32 days.Low dose of slow-releasing fumigation of grain film seal, dosage is 2.5 g/m3 standard, reduction in chemical usage is more than half the bin and grain low concentration of phosphine gas in, keeping more than 300 mL/m3 for 8 days, on some of the more difficult to control the insecticidal effect of the rustygrainbeetle.Through on from barn bulk air intake different distance of sampling points of concentration detection found, in bulk gas of early, regardless of used what way bulk gas, escape of exhaust in the phosphine of concentration are to far above phosphine of contact limit, especially away from barn bulk air intake more near of distance(5m within) range within, in North-South(vertical door axis peace line door axis) of different distance sampling points, detection found, in vertical door axis of sampling points than parallel door axis of sampling points of concentration value high, A series of points located near the warehouse wall detection value is higher than the concentration of sample points away from the warehouse, so the gas concentration to slow after fumigation.In away from bulk air intake of up distance, from bulk air intake more far, bulk gas of time more security, pressure into type mechanical ventilation continuous ventilation 2~3 d can Basic will residues of phosphine removal, sucking out type mechanical ventilation needed 5~6 d, and natural ventilation bulk gas is needed 7~10 d, in fumigation bulk gas of limit time paragraph within, the test results can for fumigation bulk gas of time select and on phosphine harmful gas of control up to guide role, this during, on bulk gas warehouse around 15~20 m within set warning or isolation, Do not allow other persons entering the area unintentionally.