■ 概述 Descriptions
◎ 閉式循環(huán)噴霧干燥系統(tǒng)是在密閉的環(huán)境下工作，干燥介質為惰性 氣體，一般為N 2，適用于有機溶劑的物料干燥有毒氣的物料或干 燥過程中易發(fā)生氧化的物料的干燥；該系統(tǒng)采用惰性氣體作為循環(huán) 氣體，對干燥的物料具有保護作用，循環(huán)氣體經歷載濕、去濕的過 程，介質可重復使用；氮氣經加熱器加熱后進入干燥塔，液體物料 經螺桿泵輸送至離心噴頭處，液體被高速循環(huán)的霧化器霧化成液 滴，在干燥塔內完成熱質交換過程，被干燥后的粉狀物料從塔底排 出，被蒸發(fā)的有機溶劑氣體在風機負壓的壓力下，把夾在氣體中的 粉塵經旋風分離器、噴淋塔除塵后飽和的有機溶劑氣體經冷凝器冷 凝成液體排出冷凝器，不凝性氣體介質連續(xù)加熱后作為干燥載體在 系統(tǒng)內重新循環(huán)使用。而常規(guī)的普通的離心噴霧干燥是通過不斷的 送風、排風達到排濕的目的，這也是防爆型閉式離心噴霧干燥設備 與普通離心噴霧干燥設備的一個明顯區(qū)別；干燥系統(tǒng)內干燥介質為 N 2，內部為正壓操作，保持一定的正壓值，如果內部壓力下降，由 壓力變送器來自動控制N 2進量，保證系統(tǒng)壓力平衡。 ◎ Seal circulation spray drying system works in a seal circumstance. the drying gas is usually inert gas, such N 2. It’s applicable for drying material with organic solvent, toxic gas and the material easy to be oxidized. adopt inert gas as circulation gas, so to protect the material to be dried. The inert gas circulates after dehumidification process. N 2 is heated and then enters into drying tower. liquid material is conveyed to centrifugal nozzle by screw pump, and then it’s atomized into the liquid mist by the atomizer, the heat transferring process is finished in the drying tower. The dry product is discharged at the bottom of tower, the evaporated organic solvent is sucked by the vacuum generated by the fan. Power or solid material will be separated in the cyclone and sprinkling tower. the saturated organic gas is drained out after it’s condensed in the condenser. the gas not condensed recycles in the system after it’s heated continuously. Ordinary normal centrifugal spray drying process is realized by air conveying and exhausting process. this is the obvious difference between explosion proof type sealed circulation centrifugal spray dryer and ordinary centrifugal spray dryer. the drying media in drying system is N 2, the interior is under positive pressure. to keep positive pressure stable, the pressure transmitter controls the inlet amount of N 2 automatically.