The invention discloses a negative-pressure 
microwave uniform spraying and 
drying device and application, belonging to the technical field of uniform 
drying devices. The negative-pressure 
microwave uniform spraying and 
drying device comprises a circulating 
material storage device, a feeder, a negative-pressure spraying 
pipe, a 
microwave heating cavity, a 
cyclone separator, a vacuum 
storage tank, a 
discharger, a water ring 
vacuum pump, a circulating 
pipe and microwave sources. The circulating 
material storage device is used for storing materials dried circularly, the feeder is used for feeding dry materials to the negative-pressure spraying 
pipe which is a channel for drying and circulating the materials, and the microwave sources are uniformly distributed inside the microwave heating cavity, two ends of which are sealed. The 
cyclone separator is connected with an outlet of the negative-pressure spraying pipe inside the microwave heating cavity and is connected with the vacuum 
storage tank and the 
discharger through a channel. The 
discharger is connected with the circulating 
material storage device through the circulating pipe. Because the materials can be sprayed under negative pressure, the device can be used for spraying, rotating and circulating the materials under a microwave 
vacuum drying condition so as to achieve the purpose of drying the materials efficiently and uniformly, meanwhile, is favorable for shortening the 
drying time by above 40% and reducing the cost of large-scale production.