flash-drying: a suitable technology for bulk solids · pdf filesurface moisture interstice...
TRANSCRIPT
July 12/13 2005
Flash-drying: a suitabletechnology for bulksolids processing
Ricard Fenollosa– Sales Manager Riera Nadeu S.A
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HOTorNOT Seminar
SOME BASIC CONCEPTS
Thermal separation: to form homogeneous groups of substanceswhichever mixed with other ones, applying heating energy.
Mix: Combination of 2 or more substances where all ingredientsare keeping its own physical identity. In a mix substances con be combined in any proportion. The properties of the mix are thecombined properties of all ingredients and these component can be recovered with no alteration from de mix without a chemicalreaction.
Drying operation is a contact mass transference (solid/liquid), where moisture mix will be transferred by means evaporation to thegaseous phase, based to the vapour pressure coming from the mixand the partial vapour pressure of the gas flow.
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More CONCEPTS
Vaporization: Runing of molecules from liquid phase to gas.
The molecules which run off are the more close to the hot surface.
So, evaporation is fastest; at same pressure level, when thetemperature is higher, due a large fraction of molecules haveenough energy to run off.
Effect of pressure:
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4
17910,0991,0
1586,0860,6
1202,0600,2
1708,0930,8
1434,0750,4
°C bar °C bar
Temp.PresiónTemp.Presión
Boiling temeperatures of H2O at different
pressures:
CONCEPT
Heat transfer: process where there is energy interchangeamong several parts or among different element of onebody whose are at same temperature.
The heat is transferred by means convection, radiationor conduction. These three processes can be carried out simultaneously, but it can occur that one of themechanisms will be predominant on the other ones.
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When is used a thermal solid-liquid separation process?
When the specs. for separation of final products are no possible toreach by means mechanical methods: centrifugation, decanting, filtration, …
When product value permits it.
Potential Secondary Effects of Drying
Tension and shrinkage (constriction) of dried material) (i.e. ceramicmaterials)
Chemical changes (pirolisis, oxidations, ….)
Bio-chemical changes (food, proteins, …)
Estrcuctural changes (modification on crystalline phase, shape, particlesize,…)
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Solid – liquid relation
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Surface moisture Interstice moisture Solvation moisture
- Easy drying Difficult drying +
POWER NEEDED BY A DRYER:
Q (total)= Q sólid + Q líquid + Q evaporation + Q others
Qsólido = ms · Ces · ∆T
Qlíquido = ml · (Cel · ∆T + Cev · ∆T’)
Qevap = ml · ∆Hvap
Qotros if there are dispersion fluid, agitation, no isolationlooses,heating of drying from outside, ….
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TYPE OF DRYERS
FLUID BED
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TYPE OF DRYERS
FLUID BED
• Batch and continuous
• Product cooling if needed.
• Only drying of wet solids
• OK for eliminate interstice and
solvation moisture.
• Low thermal efficiency.
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TYPE OF DRYERS
PADDLE DRYER
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TYPE OF DRYERS
PADDLE DRYER
• Batch and continuous.
• Only Drying of wet solids
• Lumps formation during drying (not desired)
• Low thermal efficiency.
• No possible drying of solutions/ supensions
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TYPE OF DRYERS
BICONE DRYER
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TYPE OF DRYERS
BICONE DRYER
• Batch
• Wet solids drying only.
• Low drying temperatures
• Vacuum application
• Lumps formation during drying (not desired)
• Sterilization permitted
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TYPE OF DRYER
CONE DRYER
• Batch
• Wet solids drying only.
• Low drying temeperatures
• Vacuum application
• Lumps formation during
drying (not desired)
• Sterilization permitted
• Possibility of particle
coating
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TYPE OF DRYERS
SPRAY-DRYER
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TIPOS DE SECADORES
SPRAY-DRYER
• Continuous drying
• Pump able solutions/suspensions could be dried
• High temperatures for drying possible
• Large surface and volume for drying
• Possible to obtain granules, powder.
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TIPOS DE SECADORES
SECADOR DE BANDEJAS
• Trabajo por batch
• Secado de sólidos húmedos
• Inversión económica
• Posibilidad de utilización
de vacío
• Secado no homogéneo
• Precisa molturación /
disgregación posterior
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TYPES OF DRYERS
TURBULENCE DRYING
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• Continuous drying
• Wearing effect
• Wet solids drying
• Obtaining fine powder
• High temperatures for drying
• Milling effect as complementary
TYPES OD DRYERS
LIOFILIZERS
• Batch operation.
• High operation cost
• Drying temperature very low.
• Freeze drying
• Sterile conditions
• Evaporation capacity quite limited.
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TIPOS DE SECADORES
FLASH-DRYER
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TYPES OF DRYERS
FLASH-DRYER
+ Continuous process
• Wet solids and solutions and sus
pensions able to be dried.
• Short residence time
• Nice for thermosensible products
• Possibility of sieving pneumatically
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• Fine powder obtention
• Deagglomeration of initial lumps
• Large surface of drying.
• Low operation cost
• Possibility of sterilization w/ steam
RINA - JET DRYER (TOROIDAL TYPE – HIGH TURBULENCE)
RINA - JET DRYER (P & I DIAGRAM – Flow sheet)
RINA - JET DRYER (P & I DIAGRAM – Flow sheet)
RINA-JET type S1008 unit
RINA-JET S3632 type evap 7/8 tn/h
RINA-JET (Straight type - low turbulence)
RINA-JET type S1008 R unit
RINA-JET Slurry/suspension feeding nozzle
RINA-JET Slurry feeding system
RINA-JET Operation cost calculation
RINA-JET Operation cost calculation
RINA-JET Internal heating recuperation
RINA-JET External heating recuperation
RINA-JET Heating recuperation. Loweroperation cost and low CO2 emission
RINA-JET Special performances
RINA-JET Complete Centrifugation+Drying+JetMilling set
RINA-JET ZrO-AA lining.
Wearing protection.
TABLE WITH PARAMETERS COMPARISON OF DRYERS
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SíBatch0.1-10ppm5-90 %LowLiofilizer
NoContinuo10-5.0000.1-1 %5-80 %HighTurbulence dryer
NoContinuo10-10.0000.1-1 %5-98 %HighFlash dryer
SíBatch10-1000.1-2 %10-70 %LowTray dryer
NoContinuo10-10.0000.1-5 %20-98 %HighSpray dryer
SíBatch10-100ppm5-50 %LowCone
SíBatch10-100ppm5-50 %LowBicone
Sí / NoBatch/
Continuo10-50000.1-5 %5-50 %MedPaddle dryer
Sí / No
Vacuum
necessary
5-1.000
Evap.
capacity
5-50 %
Initial
moisture
Batch/
Continuo0.1-5 %MedFluid Bed
Type of
process
Final
moisture
Thermal
power
CHOICE AND SIZING OF A DRYING SYSTEM
Physical properties of materials to be dried and dried product :
Presentation (wet solid, slurry, solution)
Viscosity,
Particle size distribution
Thermal conductivity,
Latent heat of liquid to evaporate,
Wearing (abrasion effect)
Porosity,
Fusion point - melting -,
Etc.
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CHOICE AND SIZING OF A DRYING SYSTEM
Chemical properties of dry solid and liquid:
Odour,
Thermal stability,
Flammability,
Reactivity in front drying gases,
Corrosion effect,
Existence of several crystalline phases,
Proportion solid – liquid
Etc.
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CHOICE AND SIZING OF A DRYING SYSTEM
Properties of flow of material to be dried:
Quantity of product to be dried per time unit,
Quantity od liquid to be separated,
Continuous or discontinuous process,
Material handling
Etc.
Drying kinetics
Lugar de instalación
Size of building or area to be sited.
ATEX area
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CHOICE AND SIZING OF A DRYING SYSTEM
Environmental conditions:
Noise restrictions,
Dangerous emission vapours of liquid to atmosphere.
Dangerous leakages of dried product by exhaust.
Etc.
Tech specs for dried product:
Bulk density,
Particle size distribution,
Crystalline structure,
Residual (final) moisture
Sterilization
Etc.
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CHOICE AND SIZING OF A DRYING SYSTEM
Economical considerations:
Value (added) of the product,
Operation cost (man power, energy costs, etc.)
Heat recovery possibilities,
Heat from exhausts to be used (cogeneration)
Etc.
Validation and certification:
Process validation FDA
GMP/GAMP
Certification CE-ATEX
HazOp studies
CIP Validation Riboflavin tests
SIP Validation
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SOME PRACTICAL APPLICATIONS
XXFumaric
Acid
XXIron oxide
XXXXBarium
Sulfate
X
X
X
Turb.
dryer
XXXXXXHerbicides
XXCalc.
carbonate
XXCeramic
enamels
XXXXXXAntibiótics
XXXXXXAminoacids
X
Spray
dryer
X
Flash
dryer
Tray d.
Waste water
ConeBiconePaddle
dryer
Fluid
bed
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SOME PRACTICAL APPLICATIONS
XXXXXXAPI’s
XXXXXPectine
XXXXXOxàlic àcid.
XrXSoda
bicarbonate
XXCopper
oxiclorure
XXXXXCopper
sulfate
XXXLactose
XXPlant extracts
X
Turb.
dryer
XXXPolimers
XXXKaolin
Spray
dryer
Flash
dryer
Tray d.ConeBiconePaddle
dryer
Fluid
bed
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SOME PRACTICAL APPLICATIONS
XXXOrg/Inorganic
pig,ments
XXXXXZinc Oxide
XXTartaric acid
XXrXStarch
XXXSulphur
XXXXTitanium
dioxixe
XXXXEstearates
X
Turb.
dryer
XXSilica gel
XMicro
celulose
Spray
dryer
Flash
dryer
Tray d.ConeBiconePaddle
dryer
Fuid
bed
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Some questions ...
… and t
hank yo
u for yo
ur atten
tion.