CN1054304A - Double-layer fluidized drying technology - Google Patents

Abstract

A kind of double-layer fluidized drying technology, by feeding part, the heat supply part, drying nest, air draft part and output section are formed, being used for that solid granular article such as cereal are carried out drying handles, because of in drying machine, being provided with the opposite fluid bed of two-layer incline direction, prolonged the drying time of thing to be dried in machine, reduced thing temperature inside gradient to be dried and moist gradient, thereby improved the quality of article such as cereal, and saved the energy.

Description

Double-layer fluidized drying technology

The fluidized drying method is the application of fluid technology aspect the solid particle drying, usually by the heat supply part, drying nest, feeding part, air draft part and discharging portion branch are formed, and heat supply partly provides the high hot-air with uniform temperature and flow velocity, enters drying nest, thing to be dried also enters drying nest by the feed part, but the two flows on the contrary.Drying nest mainly is a drying machine, include frame, hothouse, feed hopper, orifice plate and hot blast chamber etc., the hole of arranging by certain requirement is arranged on the orifice plate, and hothouse and hot blast chamber separated, material enters behind the hothouse promptly along the orifice plate slippage of tilting, and the indoor hot-air of hot blast enters hothouse along the hole on the orifice plate, because of the effect in hole on the orifice plate makes that hot blast is that the temperature of drying medium was both high, and flow velocity is fast again, drive the thing to be dried on the orifice plate, make it be in the suspension slippage and promptly be fluidization.The result has increased the touch opportunity of thing to be dried and drying medium, has improved drying effect.

There are two defectives in this drying process, at first, and moist thing to be dried such as cereal, one advances machine promptly contacts with high temperature gas flow, and the cereal chemistry composition is changed, and causes that cereal viscosity reduces, edible quality worsens, and protein produces thermal denaturation under temperatures involved, influence the baking quality of food.Especially under the rapid draing situation, the drying medium temperature is too high, can cause the imbalance of vaporization of cereal surface and diffusion inside, cause the cereal case-hardening, in addition Nei Bu moisture content when external diffusion to the wedge pressure effect on top layer, cause seed to crack, influence processing broken rice rate is again because heat exchanger time is very brief, the temperature height of heating, the thermograde of cereal kernel and moist gradient interact more outstanding, and after promptly cereal was heated, surface temperature sharply rose, and its kernel temperature ecto-entad progressively reduces, the temperature ecto-entad of seed conduction under the effect of temperature partial pressure, because the cereal surface is heated, surperficial moisture content is vaporized rapidly, the low also ecto-entad of its outside of a kernel humidity progressively raises, under the effect of moisture content partial pressure, moisture content spreads from inside to outside, like this, the moisture content partial pressure spreads from inside to outside, and the conduction of temperature partial pressure ecto-entad, the moisture content that hinders cereal inside to a certain extent influences dewatering effect rapidly to external diffusion.

Secondly, the energy loss of this machine is bigger, because thing to be dried and drying medium only carry out damp and hot exchange on one deck bed, drying time is short again, and exhaust heat is bigger.

The objective of the invention is to develop that a kind of to treat dry goods matter influence little, drying effect is good, the novel dried technology that capacity usage ratio is high.Be characterized in casing, being provided with the opposite two-layer orifice plate of incline direction, the upper strata orifice plate is that the feed end of upper strata fluid bed is positioned at the charging aperture place, discharge end links to each other with connection bucket, lower floor's orifice plate is that the high-end and connection bucket of lower floor's fluid bed links, low side and discharging opening link, the hot blast chamber is arranged under orifice plate, high hot-air enters down hothouse through the hole on the orifice plate earlier after entering the hot blast chamber, enter the primary drying chamber through the hole of upper strata orifice plate again, discharge by exhaust outlet then, thing to be dried is during along the up-hole plate slippage, effect because of hot-air, be fluidization, after carrying out damp and hot exchange with hot-air, enter orifice plate through connection bucket, carry out damp and hot exchange with hot-air again, make thing drying to be dried, divide fluidization regions and boiling section on the orifice plate, the percent opening of fluidization regions is littler than the percent opening of boiling section, and percent opening is the area sum of certain regional open interior on the fluidisation bed board and the percentage of the ratio of this regional fluidized bed area, and the purpose of fluidization regions is to make the solid particle fluidised formization, boiling section is for hot-air is contacted fully with thing to be dried, moisture is taken away, and boiling section has two at least, often forms by 4-6.

Advantage of the present invention is that structurally to make drying medium be that hot-air is at first by lower floor's orifice plate, behind the thing to be dried such as cereal of dry lower floor, the drying medium that has higher temperature passes through the cereal of upper strata orifice plate more for the second time, cereal is carried out the heat drying second time, and then enter atmosphere, this moment, EGT was very low, compared with original individual layer, and its capacity usage ratio is higher.

Secondly thing to be dried is continuously through two-layer fluid bed, and the dry time has increased by one times, and a precipitation rate of thing to be dried is increased.

The drying medium of thing to be dried is by the damp-heat air behind the thing to be dried in the hothouse under heating in the 3rd heating primary drying chamber, its temperature is about tens degree, play a part the preheating and drying thing, the thing to be dried vaporization that progressively heats up, make thermograde and moist gradient be tending towards relaxing, help the quality of the precipitation of thing to be dried and the thing that keeps dry.

Fig. 1 is a structure chart of the present invention.

Fig. 2 is a fundamental diagram of the present invention.

Thing to be dried as shown in the figure is after feed hopper 1 enters primary drying chamber 4, A end along the up-hole plate 10 that tilts flows to the B end, enter down hothouse 8 through connection bucket 11, hold to D by the C end of orifice plate 7 to flow to discharging opening 6,7 times hot blast chamber 9 is arranged at orifice plate, hot-air enters 9 backs, hot blast chamber and enters down hothouse 8 in the hole on orifice plate 7 earlier, enter primary drying chamber 4 through the hole of up-hole plate 10 again, discharged by waste gas outlet 5 then, 2 is casing among the figure, the 3rd, observation window is used for the operating mode in the observation machine.

Thing to be dried is sent into double-layer fluidized drying machine 13 tops through elevator 12 among Fig. 2, and hot blast is sent into drying machine 13 bottoms by heater 17 through blower fan 16, and waste gas is discharged by blower fan 15 after ash bin 14 dedustings, sends into the warehouse through the material of super-dry by elevator 18 and preserves.

Claims (4)

1, a kind of fluid drying, form by feeding part, heat supply part, drying nest, air draft part and output section, it is characterized in that the opposite fluid bed of two-layer at least incline direction is arranged in the casing 2 of drying nest, wherein the A of upper strata fluid bed 9 end links to each other with feeding part, and the D end of lower floor's fluid bed 7 links to each other with the output section.

2, drying process according to claim 1 is characterized in that between the C end of the B of upper strata fluid bed 9 and lower floor's fluid bed 7 connection bucket 10 being arranged.

3, drying process according to claim 1 is characterized in that fluid bed includes fluidization regions and boiling section, and the percent opening of fluidization regions is littler than the percent opening of boiling section.

4, drying process according to claim 1 is characterized in that the boiling section on the fluid bed has two at least.

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