CN102274703A - Large-scale continuous energy-saving fluidized bed spraying, granulating and drying process - Google Patents

Abstract

The invention discloses a large-scale continuous energy-saving fluidized bed spraying, granulating and drying process, belonging to the granulating and drying technology. The process comprises the following steps of: conveying a feed liquid to a two-fluid spray gun to be atomized into tiny drops under the effect of compressed air; uniformly spraying and coating the tiny drops on the surface of a seed crystal granule in a granulation fluidized bed; meanwhile, drying the seed crystal granule under the common heating effect of hot air and a built-in heater; firstly screening out lump materials and oversize granule materials from the discharged materials, and then sending the rest materials in a cooling fluidized bed; after the discharged materials are screened, crushing the materials of which the size is more than the qualified grain size by using a crushing machine; then mixing the crushed materials and the materials of which the size is less than the qualified grain sizes as the seed crystal which is returned to the granulation fluidized bed to be re-granulated; and sending the materials with the qualified grain size into a finished product warehouse as a product. The spraying, granulating and drying process is strong in material adaptability; the granule products which are large in specific weight, high in strength, good in sphericity, uniform in granularity and hard to absorb moisture can be obtained, and the continuous large-scale production is realized; and the material is free from the problem of pyrolysis, and the discharged tail gas has less pollution to the environment.

Description

The energy-saving fluidized bed spray granulation drying process of Large Scale and Continuous

Technical field

The present invention relates to a kind of granulating and drying technology, the energy-saving fluidized bed spray granulation drying process of especially a kind of Large Scale and Continuous.

Background technology

In every field such as chemical industry, food, pharmacy and environmental protection, there is a large amount of liquid materials to need dry the processing, the main drying mode of liquid material has: spray-drying, slurry-spraying pelletizing rotary drying, one-step palletizing drying, roller drying etc.Different drying modes has different drying properties and material application scope.Wherein the material adaptability of spray dryer is stronger, and the production capacity wide ranges is most widely used, by spray-drying can be loosened, tiny powdery product.The unit treating capacity of slurry-spraying pelletizing whizzer is bigger, by force, easily glue the dry materials of wall applicable to moisture absorption, can produce closely knit bulky grain product, be applied to the biological compound fertilizer production field, the slurry-spraying pelletizing rotary drying need adopt high-temperature hot air or hot flue gas as thermal medium more, material temperature height in the dry run, easy pyrolytic, tail gas has pollution to environment, and along with improving constantly of environmental requirement, its application is restricted.The one-step palletizing drying be in small-sized fluid bed by mist projection granulating and drying, once obtain the mode of production of granular product, intermittent operation, unit production capacity is little, is mainly used in multiple batches of, small lot batch manufacture in the pharmaceutical industry.

And the spray dryer of employing and fluid bed combination, with the resulting powder-product of spray-drying in fluid bed, spray agglomeration granulation and redrying, can be loosened, porous, frangible and bulk density smaller particles product, the resulting product of this drying mode has good flowability and dissolubility usually, uses comparatively extensive at field of food.

But a large amount of liquid materials is arranged still in industrial production, multiple tunning and spherical calcium chloride, granular urea etc. as the biochemical industry industry, because in dry run, have the strong moisture absorption, easily characteristic such as sticking wall caking is difficult to drying, perhaps, take above-mentioned traditional drying mode to solve because dried product granularity, granule strength, dissolution characteristics etc. are had specific (special) requirements.Tunning with the biochemical industry industry is an example, sweat is the critical process process of multiple antibiotics production such as several amino acids such as lysine, tryptophan, threonine and salinomycin, terramycin, aureomycin, penicillin, in the sweat except that generating active ingredient, also can generate a lot of accessory substances, especially active ingredient is purified and separate the biological waste liquid that the back produces, these tunning amounts are big, complicated component, separate, dry difficulty, in dry run because have the strong moisture absorption, easy characteristic such as sticking wall, mobile difference and be difficult to handle.At present, good solution is not also arranged.

Summary of the invention

Technical assignment of the present invention is to provide a kind of Large Scale and Continuous energy-saving fluidized bed spray granulation drying process at above-mentioned deficiency of the prior art, it is strong that the energy-saving fluidized bed spray granulation drying process of this Large Scale and Continuous has material adaptability, is particularly suitable for because the strong moisture absorption, easily characteristic such as sticking wall causes the liquid material that can't adopt spray-drying to produce; Can to obtain big proportion, high strength, good sphericity, epigranular, be difficult for the grain products of the moisture absorption, can be fit to mix the requirement of using in order satisfying with other granule materials as fields such as feed addictive, fertilizer; Realized Large Scale and Continuousization ground large-scale production; There is not the pyrolytic problem in material, and the discharge tail gas environmental pollution is little.

The technical solution adopted for the present invention to solve the technical problems is: the feed liquid in the slurry tank is pressed and delivered to two Fluid sprayers by feed pump, under the compressed air effect, be atomized into fine drop, be sprayed on the seed particles surface that is in fluidized state in granulating fluidized bed equably, grow up gradually by reunion and coating effect, simultaneously hot-air and granulating fluidized bed in the common heat effect of internal heater under be dried, the material of discharging through the first discharging rotary valve from granulating fluidized bed has the particle size range than broad, earlier send into first vibratory sieve and screen out piece material and excessive granule materials through first elevator, send into cooling bed then, carry out depth drying and cooling and reach needed moisture of finished product and temperature requirement, the material of discharging through the second discharging rotary valve from cooling bed is sent into second vibratory sieve through second elevator, after screening, greater than the material of qualified particle diameter by after the crusher in crushing, return granulating fluidized bed again granulation as crystal seed through the charging rotary valve with the material less than qualified particle diameter, the material of qualified particle diameter is sent into finished product bin as product.

Granulating fluidized bed and cooling bed adopts air as fluidizing agent, air is via first air blast and the pressurization of second air blast, by aerodynamic effect solid particle is formed the fluidized-bed layer with fluidization character in granulating fluidized bed and cooling bed, be provided with internal heater in granulating fluidized bed, dryer section and cooling section in the cooling bed are respectively equipped with internal heater and built-in cooler, dry materials and needed heat of cooling and cold, a part is provided by hot-air and cold air, and a part is provided by the internal heater and the built-in cooler that are submerged in the fluidisation bed of material in addition.

Described enter granulating fluidized bed hot-air for first air blast with granulating fluidized bed between be provided with first air heater, heat by first air heater and obtain hot-air; The described hot-air of cooling bed dryer section that enters is for being provided with second air heater between second air blast and cooling bed, obtain hot-air by the heating of second air heater, before air is through first air blast and second air blast, filter through first air cleaner and second air cleaner earlier.

The tail gas of granulating fluidized bed discharge passes through cyclone separator earlier, most of fine granular materials of carrying secretly in the tail gas is collected, rotary valve through the cyclone separator bottom returns granulating fluidized bed as crystal seed, the tail gas of discharging from cyclone separator carries out after the dedusting by the first air-introduced machine emptying through first sack cleaner, turn back to slurry tank after the powder processization slurry jar dissolving that first sack cleaner is collected, utilize again again.

The tail gas that cooling bed is discharged directly enters second sack cleaner, and fine grained of being collected by second sack cleaner and dust return granulating fluidized bed as crystal seed, and the tail gas after the purification is by the second air-introduced machine emptying.

The energy-saving fluidized bed spray granulation drying process of Large Scale and Continuous of the present invention is compared with prior art, have following outstanding beneficial effect: (1) material adaptability is strong, is particularly suitable for because the strong moisture absorption, easily characteristic such as sticking wall causes the liquid material that can't adopt spray-drying to produce; (2) can obtain big proportion, high strength, good sphericity, epigranular, be difficult for the grain products of the moisture absorption, can be fit to mix the requirement of using in order to satisfy with other granule materials as fields such as feed addictive, fertilizer; (3) serialization, large-scale production have been realized; (4) energy-conservation remarkable with emission reduction effect, adopt low temperature drying, there is not the pyrolytic problem in material, and the discharge tail gas environmental pollution is little.

Description of drawings

Accompanying drawing 1 is the flow chart of the energy-saving fluidized bed spray granulation drying process of Large Scale and Continuous;

Description of reference numerals: 1, first air cleaner, 2, first air blast, 3, first air heater, 4, slurry tank, 5, feed pump, 6, two Fluid sprayers, 7, granulating fluidized bed, 8, cyclone separator, 9, first sack cleaner, 10, first air-introduced machine, 11, change the slurry jar, 12, rotary valve, 13, the charging rotary valve, 14, the first discharging rotary valve, 15, first elevator, 16, first vibratory sieve, 17, second air cleaner, 18, second air blast, 19, second air heater, 20, cooling bed, 21, second sack cleaner, 22, second air-introduced machine, 23, the second discharging rotary valve, 24, second elevator, 25, second vibratory sieve, 26, disintegrating machine, 27, conveying worm, 28, finished product bin, 29, internal heater, 30, built-in cooler.

The specific embodiment

With reference to explaining below the energy-saving fluidized bed spray granulation drying process work of 1 pair of Large Scale and Continuous of the present invention of Figure of description.

The energy-saving fluidized bed spray granulation drying process of Large Scale and Continuous of the present invention the steps include: that mist projection granulating and dry run finish in granulating fluidized bed 7.Feed liquid in the slurry tank 4 is pressed and delivered to two Fluid sprayers 6 by feed pump 5, under the compressed air effect, be atomized into fine drop, be sprayed on the seed particles surface that is in fluidized state in granulating fluidized bed 7 equably, grow up gradually by reunion and coating effect, be dried under the common heat effect of the internal heater 29 in hot-air and granulating fluidized bed 7 simultaneously, the material of discharging through the first discharging rotary valve 14 from granulating fluidized bed 7 has the particle size range than broad, earlier send into first vibratory sieve 16 and screen out piece material and excessive granule materials through first elevator 15, send intocooling bed 20 then, carry out depth drying and cooling and reach needed moisture of finished product and temperature requirement, the material of discharging through the second discharging rotary valve 23 from cooling bed 7 is sent into second vibratory sieve 25 through second elevator 24, after screening, greater than the material of qualified particle diameter by after disintegrating machine 26 fragmentations, return granulating fluidized bed 7 again granulations as crystal seed through charging rotary valve 13 with the material less than qualified particle diameter, the material of qualified particle diameter is sent into finishedproduct bin 28 as product.

Granulating fluidized bed 7 andcooling bed 20 adopt air as fluidizing agent, air is viafirst air blast 2 and 18 pressurizations of second air blast, by aerodynamic effect with solid particle granulating fluidized bed 7 andcooling bed 20 in form fluidized-bed layer with fluidization character, be provided with internal heater 29 in granulating fluidized bed 7, dryer section and cooling section in thecooling bed 20 are respectively equipped with internal heater 29 and built-incooler 30, dry materials and needed heat of cooling and cold, a part is provided by hot-air and cold air, a part is provided by the internal heater 29 and the built-incooler 30 that are submerged in the fluidisation bed of material in addition, because the thermal efficiency height of built-in heat exchanger, can savesteam consumption 20～30%, reduce installedpower 20～30%, reduce exhaust emissions amount about 50%.

Described granulating fluidized bed 7 the hot-air of entering is for being provided with first air heater 3 between first air blast 2 and granulating fluidized bed 7, heat by first air heater 3 to obtain hot-air; The described hot-air ofcooling bed 20 dryer section that enters is for being provided with second air heater 19 betweensecond air blast 18 andcooling bed 20, obtain hot-air by 19 heating of second air heater, before air is through first air blast 2 andsecond air blast 18, filter through first air cleaner 1 and second air cleaner 17 earlier.

Granulating fluidized bed 7 tail gas of discharging are earlier by cyclone separator 8, most of fine granular materials of carrying secretly in the tail gas is collected, rotary valve 12 through cyclone separator 8 bottoms returns granulating fluidized bed 7 as crystal seed, the tail gas of discharging from cyclone separator 8 carries out after the dedusting by 10 emptyings of first air-introduced machine through first sack cleaner 9, turn back to slurry tank 4 after powder processization slurry jar 11 dissolvings that first sack cleaner 9 is collected, utilize again again.

The tail gas thatcooling bed 20 is discharged directly enters second sack cleaner 21, and fine grained of being collected by second sack cleaner 21 and dust return granulating fluidized bed 7 as crystal seed, and the tail gas after the purification is by 22 emptyings of second air-introduced machine.

Described first sack cleaner 9 and second sack cleaner 21 also can adopt wet scrubber, for extremely strong materials of hygroscopicity such as spherical calcium chloride, granular ureas, can not adopt sack cleaner, can only use wet scrubber.

Described first elevator 15 and second elevator 24 are bucket elevator or pneumatic conveyer.

Described two Fluid sprayers 6 adopt exterior mixing two Fluid sprayers, are used for feed liquid is atomized under compressed-air actuated effect, make it to spray to equably the seed particles surface in granulating fluidized bed 7.

Adopt this technology can obtain big proportion, high strength, good sphericity, epigranular, be difficult for the grain products of the moisture absorption.The particle diameter of the granule materials of being produced can be adjusted arbitrarily between 0.3～5mm.

This technology can be applicable to the large-scale continuous drying-granulating production of liquid materials such as the multiple zymotic fluid (as multiple antibiotic such as several amino acids such as lysine, tryptophan, threonine and salinomycin, terramycin, aureomycin, penicillin) of biological chemical field and spherical calcium chloride, granular urea.

Except that the described technical characterictic of specification, be the known technology of those skilled in the art.

Claims (5)

1. the energy-saving fluidized bed spray granulation drying process of Large Scale and Continuous, it is characterized in that: the feed liquid in the slurry tank is pressed and delivered to two Fluid sprayers by feed pump, under the compressed air effect, be atomized into fine drop, be sprayed on the seed particles surface that is in fluidized state in granulating fluidized bed equably, grow up gradually by reunion and coating effect, simultaneously hot-air and granulating fluidized bed in the common heat effect of internal heater under be dried, the material of discharging through the first discharging rotary valve from granulating fluidized bed has the particle size range than broad, earlier send into first vibratory sieve and screen out piece material and excessive granule materials through first elevator, send into cooling bed then, carry out depth drying and cooling and reach needed moisture of finished product and temperature requirement, the material of discharging through the second discharging rotary valve from cooling bed is sent into second vibratory sieve through second elevator, after screening, greater than the material of qualified particle diameter by after the crusher in crushing, return granulating fluidized bed again granulation as crystal seed through the charging rotary valve with the material less than qualified particle diameter, the material of qualified particle diameter is sent into finished product bin as product.

2. the energy-saving fluidized bed spray granulation drying process of Large Scale and Continuous according to claim 1, it is characterized in that: granulating fluidized bed and cooling bed adopts air as fluidizing agent, air is via first air blast and the pressurization of second air blast, by aerodynamic effect solid particle is formed the fluidized-bed layer with fluidization character in granulating fluidized bed and cooling bed, be provided with internal heater in granulating fluidized bed, dryer section and cooling section in the cooling bed are respectively equipped with internal heater and built-in cooler, dry materials and needed heat of cooling and cold, a part is provided by hot-air and cold air, and a part is provided by the internal heater and the built-in cooler that are submerged in the fluidisation bed of material in addition.

3. the energy-saving fluidized bed spray granulation drying process of Large Scale and Continuous according to claim 2, it is characterized in that: described enter granulating fluidized bed hot-air for first air blast with granulating fluidized bed between be provided with first air heater, heat by first air heater and obtain hot-air; The described hot-air of cooling bed dryer section that enters is for being provided with second air heater between second air blast and cooling bed, obtain hot-air by the heating of second air heater, before air is through first air blast and second air blast, filter through first air cleaner and second air cleaner earlier.

4. the energy-saving fluidized bed spray granulation drying process of Large Scale and Continuous according to claim 1, it is characterized in that: the tail gas of granulating fluidized bed discharge passes through cyclone separator earlier, most of fine granular materials of carrying secretly in the tail gas is collected, rotary valve through the cyclone separator bottom returns granulating fluidized bed as crystal seed, the tail gas of discharging from cyclone separator carries out after the dedusting by the first air-introduced machine emptying through first sack cleaner, turn back to slurry tank after the powder processization slurry jar dissolving that first sack cleaner is collected, utilize again again.

5. the energy-saving fluidized bed spray granulation drying process of Large Scale and Continuous according to claim 1, it is characterized in that: the tail gas that cooling bed is discharged directly enters second sack cleaner, fine grained of being collected by second sack cleaner and dust return granulating fluidized bed as crystal seed, the tail gas after the purification is by the second air-introduced machine emptying.

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