Concentration of liquid flashing dryer dryer efficiency and operational stability has a significant impactConcentration of liquid flashing dryer dryer efficiency and operational stability has a significant impact, as the solid content increases, the required dehydration rate is correspondingly decreased. But the corresponding increase in the viscosity of the liquid, is bound to bring difficulties to the spray, if uneven distribution of liquid in the dryer, inert surface layer is thick and difficult to evenly, significantly affect the boiling effect of inert particles. Layer thickening reduces the effect of mass transfer of water, diffusion is reduced accordingly, is not conducive to dry. While increasing solid content can reduce water evaporation, but due to the low rate of mass transfer could even more uneconomic.
flash dryer low solid content of the feed, no doubt the increased evaporation of water, calories consumed has also increased. But at this point you can use higher flow medium temperature the bed temperature has not increased significantly. Due to import and export gas has a greater temperature difference, so it will improve the efficiency of evaporation.
according to different source, in the actual production of the solid content of the feed is also a great difference. In fact, any kind of liquid has a critical rate of solid, under these conditions, water evaporation rate is very high, and inert particles on the membrane material can successfully cut down, this is the best argument, but to experiment to get it.
If you take intermittent spray method, solid content of the feed can be higher, because joined the stream of the liquid becomes bad, but stopped after the spray, with materials dry and inert particles from the surface of cutting down, good flow in fluidized beds and restore the original state, intermittent feeding is also commonly used as a method of operation. But in order to prevent stop charging when temperature of the layer, the best appropriate spray a small amount of low solid content feed to control the bed temperature.
flash dryer vibration source can make the original mass and heat transfer control of Jin is broken, thus have different effects on dry strength. Experimental results show that the effect of amplitude and frequency on an area of dry strength, viscosity also exhibit different characteristics of the feed, large drying viscous material, used big amplitude, amplitude carrier collision force could be improved, you can quickly update the contact surface of the material and the hot air to improve the transfer rate. But smaller for the viscosity of liquid vibration frequency on the strength of the effect is more noticeable, the amplitude is not obvious. Operation there is an extreme, experimental condition extremum 314 mm, when the amplitude exceeds this value, with the increase of amplitude, dry strength decreased. Because when the viscosity of the liquid is smaller, the carrier does not disperse materials is very important, improve the frequency of collisions between the carrier and the material increase transfer of heat energy, so drying intensity increases. High amplitude caused by carrier carrier reduced contact with the materials, and thus reduce the dryness.