1. Phosphine circulating fumigation technology; use circulating fumigation equipment to force fumigant vapor circulation to promote full diffusion of fumigant vapors; 2. Phosphine generator outside the warehouse; Hydrogen gas generation equipment); 3, Phosphine generator; Adopt aluminum phosphide to add water to controllably generate phosphine gas and add it; 4. Decompression release equipment; Temperature release container, stainless steel hose, etc .; 5, Phosphine cylinders for drug delivery; Phosphine cylinders, decompression release devices, Circulation fumigation: 1. Phosphine circulation fumigation technology Circulating fumigation equipment is used to force the fumigant gas circulation to promote the fumigation insecticidal technology in which the fumigant gas is quickly and evenly distributed in the grain pile. 2. Phosphine generator outside the warehouse It consists of a phosphine generator outside the warehouse (or other phosphine gas generating equipment, carbon dioxide cylinders, decompression release equipment and control equipment, etc.). 3. Phosphine generator The phosphine gas is controlledly generated by the reaction of adding aluminum phosphide and water, and mixed with the added carbon dioxide gas in the machine to form a phosphine and carbon dioxide mixed gas application device. 4. Decompression release device It consists of a pressure reducing regulator, a temperature release device, and a stainless steel hose. Its function is to change the liquefied gas in the cylinder from a high pressure state to a low pressure state, from a liquefied state to a gas state, and to transport it safely into the circulation pipeline through the metering and control equipment. 5. Phosphine cylinder spraying equipment It consists of phosphine steel cylinder, decompression release device, metering device, control device and mobile device. 6.Circumferential fumigation with grain application The method of applying the aluminum phosphide agent to the grain surface is applied to the grain surface, and then by means of a circulating fan, The generated phosphine gas is circulated through the grain pile for fumigation. 7.Circumferential fumigation under the membrane The surface layer of the grain stack in the warehouse is covered and sealed with a film, and a circulating fumigation method is performed using a circulating device such as a return pipe buried under the film. 8.Circular fan Fans with airtight, explosion-proof (without motor) and anti-phosphine corrosion performance, the wind pressure does not exceed 1000 Pa, and the air volume does not exceed 1000 m3 / h. 9, fixed circulation equipment Installation for fixing the circulation fan and the circulation pipeline on the warehouse wall. 10, mobile circulation equipment The circulation fan is fixed on the movable vehicle body, and the return pipe of the circulation pipeline is fixed on the warehouse wall. The other pipes are installed during fumigation, and can be removed and moved after fumigation. 11. Gas sampling equipment It consists of sampling tip, sampling tube, sampling valve and detection box, etc., and is used to extract gas samples in the warehouse and pipeline. 12, phosphine detector, alarm, detection tube Phosphine detector: An instrument used to detect the concentration of phosphine in a gas sample. Phosphine alarm: An instrument used for leak detection of circulating equipment, environmental safety monitoring and alarm. Phosphine gas detection tube: a longer type detection tube for detecting the concentration of phosphine gas. 13.Maintaining the application method The operation mode of maintaining the concentration of phosphine gas in the fumigation environment by applying or replenishing according to the airtightness of the warehouse. 14. Fumigation concentration The minimum phosphine concentration at the detection point in the grain pile after the circulation is almost uniform, the unit is milliliters per cubic meter (ml / m3). 15. Confinement time After application, maintain the fumigation confinement time for the phosphine concentration in the grain pile to reach the set concentration or higher. 16, unit dosage The amount of aluminum phosphide (or phosphine) used per unit of fumigation volume is expressed in grams per force square meter (g / m3). 17.Fumigation volume The total volume of the fumigation in a closed environment. The total fumigation volume of the whole warehouse is the sum of the volume of the space and the volume of the grain pile. The total volume of the fumigation under the membrane is only the grain volume. Second, the quality requirements of phosphine circulation fumigation equipment and instruments Phosphine circulating fumigation equipment is composed of three parts: spraying equipment, circulating equipment, and testing equipment. The quality of the equipment and instruments used should meet the requirements of GB / T17913.
3. Phosphine circulation fumigation operation procedure
Basic situation investigation-making a plan-preparation before application-fumigation application-fumigation process inspection and problem treatment-gas diffusion and effect inspection-aftercare work.
1. Basic situation investigation
(1) Food situation inspection
1) Understand the type, origin, moisture, impurities, quantity, purpose, storage time, storage form, grain temperature, warehouse temperature, temperature, humidity and atmospheric humidity of the grain, and weather forecast.
2) Find out the type, density, occurrence state and location of the pests; if possible, try to understand or test the resistance of the pests.
(2) Warehouse and environmental investigation.
1) Understand the type, structure, tightness and related facilities of the warehouse.
2) Understand whether the surrounding environment of the warehouse can be fumigated.
3) Understand the past fumigation treatment.
2. Make a plan
The formulation of the circulation fumigation plan should be based on the principles of safety, economy, and effectiveness, with the purpose of killing all insect species and insect states in the grain pile, determining the method of application and maintaining the fumigation concentration, the amount of medication, and the fumigation confinement time.
(1) Application method
Circulation fumigation and application methods should be determined according to the conditions of stored grain, facilities, and the warehouse and its environment. There are three application methods for fumigation in the whole warehouse or under the membrane. That is: the application of phosphine generator outside the warehouse, the application of phosphine cylinders, and the application of aluminum phosphide flour. When using other application methods to carry out the phosphine circulation fumigation, ensure the safety of fumigation operation and fumigation environment.
(2) Determination of phosphine concentration and sealing time
环流熏蒸中不同密闭时间、温度和虫种时设定磷化氢浓度参照表 单位为毫升每立方米 当有强抗性谷蠹集中发生并导致发热，或有强抗性米象和锈赤扁谷盗时，建议磷化氢浓度采用300 ml/m3～500 ml/m3。 Phosphine concentration and confinement time for circulating fumigation are determined according to different food temperatures and insect species. Phosphine concentration is set for different confinement time, temperature, and insect species in circulating fumigation. The reference table unit is milliliters per cubic meter. It is recommended that the concentration of phosphine should be 300 ml / m3 ～ 500 ml / m3 when the radon occurs in a concentrated way and causes fever, or has strong resistance to rice elephants and rusty stalks.
选定单位用药量。 According to the set fumigation concentration, and taking into account factors such as grain pile adsorption and warehouse leakage, the unit dosage of medicine is selected. 浓度差值参照表2确定补充用药量；采用磷化氢的其它药剂形式时，可参考表2计算用药量；表2环流熏蒸磷化铝片剂（或丸剂）单位用药量； When supplementary application is needed, refer to Table 2 to determine the supplementary dosage according to the difference between the actual measured minimum concentration and the set concentration. For other forms of phosphine, refer to Table 2 to calculate the dosage; Table 2 Circulating fumigation of aluminum phosphide Tablet (or pill) unit dosage;
(4) Application method to maintain fumigation concentration; maintenance is determined according to the enclosed condition of the warehouse and the change in the concentration of phosphine in the warehouse; 1) one-time application; when the sealed performance of the warehouse reaches the required requirements, it is counted; The concentration of phosphine in the grain pile during the fumigation and confinement period is reduced to the set concentration or below;
(5) Set sampling points for radon gas; refer to Table 2 for the difference in room concentration to determine the supplementary dosage. The dose is the volume in the fumigation environment times the unit dose.
When using other forms of phosphine, refer to Table 2 to calculate the dosage.
Table 2 Unit dosage of fumigated aluminum phosphide tablets (or pills)
(6) Application method to maintain fumigation concentration