Research On Key Technology Of Phosphine Fumigation And Waste Gas Purification In Tobacco Mellowing Warehouse

In order to use pesticides phosphine safely, efficiently and effectively in processing of tobacco leafmellowing, the dosing way of phosphine, lethal effect to Lasioderma serricorne, gas purification, safedisposal of residues and other key technologies were studied in No.4warehouse mellowing layerreservoir of ShanDong Tobacco Industrial Co., Ltd. The main results are as follows:When56%aluminum phosphide was applied artificially under at the concentration with5g/m3,after48h, the phosphine concentration in the fumigation room and tobacco box reached the requiredinsecticide concentration.applied after72h, the concentration of the phosphine gas was consistence inthe fumigation room and tobacco box. The phosphine generator was used twice in the followingresearch, the phosphine density reached200mL/m3at every investigating point after12h with firstapplication of phosphine generator, After second application with phosphine generator, the phosphinegas density was even consistent. The method of phosphine generator showed some advantages includingthat elicited the36h reaction time, and complete reaction of aluminium phosphide tablet, and reduced2/3time cost in Compared with the artificial application.In the same temperature and humidity and under the same concentration of phosphine, thevirulence of phosphine on the adult of Lasioderma serricorne is greater than on the larvae. Temperaturehas significant effect on the insecticidal effect of phosphine sealed fumigation, high-temperaturefumigation is better than the low-temperature insecticidal effect. The death rate of Lasiodermaserricorne increases with the lethal dose CT value increasing within a certain phosephine concentrationand time range, it shows that the insecticidal effect of low concentration in long time treatment is betterthan that of high concentration in short-time treatment.The FJL2000phosphine gas purifier was used in this study under the way of “exhaust purification+fill of fresh air”. Air change once every two hours, in the fumigation storehouse the phosphine gasdensity drops from400mL/m3to about1mL/m3, the phosphine gas density drops from400mL/m3to6mL/m3in the htobacco box. Disperses and purification7h, purifier should close down settles for8h,which enables the smoke box interior high potency the phosphine gas to proliferate naturally to thefumigation storehouse, and enhance the efficiency of disperse. The decrease rate of the phosphine gas instorehouse was higher than that in smoke box, there were two downward gravities of the phosphine gas before and after close down purifier. The phosphine gas showed better penetrability to the leaf tobaccoand there was no significantly different among the different depth of tobacco box.The specific process formulations of aluminum phosphide residues was determined in this study,The12mL nitric acid, the6mL perchloric acid and the1.3g copper catalyst were added into100galuminium phosphide pesticide, then heated at90℃for30min. After application by using the abovemethods, the waster water may achieve GB8978-1996"Sewage Synthesis Emission standard" and thesecond-level emission standard of CJ3082-1999"Sewage Disperses into Urban Sewer Water standard".These methods realized the virulent aluminium phosphide waste residue or waste liquid detoxificationprocessing.