Spray Coolers

What is spray cooler

Spray cooling is defined as a process by which a melt is formed into particles of spherical shape by spraying the melt into a cooling chamber through which ambient or cooled, low temperature air is passing. Rotary (wheel) atomizers and nozzles are used to spray the melt. Spray cooling finds applications in the chemical, food, and pharmaceutical industries. It is a most convenient method of transforming melted feed stocks into free-flowing particulates of controlled particle size.

Reference Products: spray cooler is used for following products

Ø  Fats Glycerides Hydrates

Ø  Inorganic / organic melts

Ø  Stearic acid/stearates

Ø  Waxes

Ø  GLYCEROL MONOSTEARATE(GMS) 

The selection of a spray cooling plant design depends upon the particle size specified as well as the need for post-cooling / crystallization for the cooled product

Fine particle products with mean particle size 50-150 micron; co-current conical based cooling chamber with high-speed rotary atomization.

Coarse particle products with mean particle size 150-300 micron; conical based cooling chamber with fountain nozzle.

Utilizing closed cycle spray cooling enables optimization of cooling energy requirements and product quality

Plant operation in warm and humid climates will normally require the ambient air supply to the spray cooler to be dehumidified and cooled. To reduce the extra energy consumption involved, it is common practice to recycle the process air, thereby minimizing the load on the dehumidification/cooling unit.

Main Components of Spray cooler-

Ø  Cooling Chamber

Ø  Conveying Duct

Ø  Cyclone Separator

Ø  Centrifugal fans

Ø  Heat exchanger

Ø  Feed tank- Jacketed

Ø  Feed Pump

Ø  Feed line and spraying nozzle

Ø  Instruments- Pressure Switch, SRV, Temperature controller, VFD

Working Principle of the spray Cooler-

Ø  Hot melt is sprayed in the cooling chamber consists of cool air.

Ø  Heat transfer takes place between hot particle and cool air, forming fine powder.

Ø  Proper cooing and particle hardening  of particle takes place in conveying duct.

Ø  In cyclone separator air and powder gets separated and powder is discharged through rotary vale.

Ø  Air containing less amount of fine particles comes to centrifugal fan.

Ø  The air gets chilled in heat exchanger and again supplied to the chamber.

Salient features of spray cooler manufactured by Supreet-

Ø  Single point collection of powder. This ensures less handling of finish product.

Ø  No mitre bends in the ducting avoids material deposition in the system.

Ø  Pressure from 10 kg/cm² to 200 kg/cm² can be achieved.

Ø  Thick slurries can be handled and sprayed by giving high pressure.

Ø  Very low maintenance is required (periodical cleaning of heat exchanger tubes).

Ø  All valves are jacketed only- avoids external heating of valve body during start up.

Ø  Total plant is automatic and no man interference is required. Only one man for the powder collection is required

 

The nozzle atomizer type spray coolers is used to spray the melt formed particles of spherical shape by spraying the melt into a cooling chamber through which ambient or cooled, low temperature air is passing. These are applied in the chemical, food, and pharmaceutical industries. This has proven to be most convenient method of transforming melted feedstock into free-flowing particulates of controlled particle size.