Flash Dryer
Flash Dryer
Clair Flash Dryers are used for drying a variety of wet cakes through a fully automatic process i.e. that require no handling or human involvement. The feed rate is adjusted automatically as per the variation in moisture content to ensure consistent product quality – every single time.
The principle of Flash Drying is to evaporate the surface moisture instantaneously. The word “flash” is used, as the drying time varies from a few milli seconds to few seconds. This makes it ideal for drying heat sensitive, easily oxidized, materials that cannot be exposed to process conditions for extended periods.
Flash Dryers operate effectively on throughput rates varying from a few kilograms per hour up to several tons per hour (based on the bulk density of the product). Clair Flash Dryers are an efficient method of drying products such as slurries, pastes and sludge (most with back mixing), friable filter cakes, powders and granules.
Flash drying is a continuous operation process where the wet material (to be dried) is fluidized in hot air and pneumatically conveyed along the height of the dryer. Hot air is taking from the hot air generator or from the available existing heat source in the plant. Since the system has relatively low residence time and the moisture is flashed off, a significant amount of evaporative cooling takes place in the system. This allows higher inlet temperatures to be used than in many other dryers without unduly heating the product. Higher inlet temperatures also increase the overall dryer efficiency.
Clair flash dryer is energy efficient, requiring no intermediate material handling. These unique features make it an ideal replacement for conventional tray and rotary drying equipment’s. The power consumption comparatively is ~15% lesser than the conventional type dryer and is ~40% less in annual maintenance cost.
Exclusive features of our Flash Drying system:
3D model of our Flash Dryer
We have 5 installations of Flash Dryers in India with capacities ranging from 20 TPH to 50 TPH for different applications such as drying of wet slag (GGBS), Pond Ash and Coffee spent. In case of Slag and Pond Ash, the moisture content was successfully reduced from as high as 25% to less than 1%, whereas in case of Coffee Spent, the moisture content was reduced from 65% to less than 35%.
Besides just the Flash Dryer, we have the provided the complete system for drying which includes Wet Raw Material handling, Screening, Hot Air Generator (HAG) system for generating hot air using coal / petcoke / biomass etc., Dried material handling and Conveying systems either to silos or up to transfer vehicles. The system is also provided with pollution control system (Cyclone/Process Bag House) for handling dust / fines emissions to restrict to < 10 mg/Nm3.
In one of our installations, Clair has provided flash dryer to reduce moisture percentage in the wet material from 25% (Max) in slag to <1% for one of the renowned Cement manufacturers in India. Hot air at 350°C was generated for this process using HAG using coal as fuel. Since HAG uses indigenous coal as fuel to generate hot air, which has a temperature range of up to 800°C, bleed air damper is provided to decrease the temperature of the hot air to 350°C. The dust arising after drying of wet slag was handled by the cyclone, followed by bag filter which is situated after the flash dryer tower. The specific power consumption is about 26k W/Ton of material. The Specific power consumption depends on the System scheme and quality of Heat source.
The Slag (GGBS) is fed in to the dryer through a double flap valve which falls in to the Flash Dryer and the typical conveying velocity and lifting velocity will be attained due to venturi provided in the dryer assembly. The GGBS particles are vented out through the top of the dryer assembly in to the cyclone and bag filter assembly provided. The particles which are not vented due to the suction created by the fan are collected at the bottom of the dryer; the Cyclone and Bag filter material is transferred to Dry Slag Storage bin.
| S. No. | Location | Country | Year | Industry | Material Dried | Capacity (TPH) | Inlet Moisture (%) | Outlet Moisture(%) |
| 1 | ORISSA | INDIA | 2017 | CEMENT | WET SLAG | 25 | 18 | 1 |
| 2 | ANDHRA PRADESH | INDIA | 2015 | COFFEE | SPENT COFFEE | 2 | 65 | 30 |
| 3 | GOA | INDIA | 2008 | CEMENT | WET SLAG | 20 | 20 | 1 |
| 4 | ANDHRA PRADESH | INDIA | 2006 | CEMENT | WET SLAG | 30 | 12 | 1 |
| 5 | RAJASTHAN | INDIA | 2022 | CEMENT | FLY ASH | 50 | 30 | 1 |
And many more…
We have 6 installations of Flash Dryers in India with capacities ranging from 20 TPH to 50 TPH for different applications viz. Moist Slag (GGBS), Pond Ash and Coffee spent. In case of Slag & Pond Ash, the moisture content was successfully reduced from as high as 35% to less than 1%, whereas in case of Coffee Spent, the moisture content was reduced from 65% to less than 30%.
Besides just the Dryer, the complete system was also provided for Wet Raw Material handling, Screening, HAG system for generating hot air using coal / petcoke / biomass etc., Dry material handling & Conveying systems either to silos or up to transfer vehicles, and most importantly pollution control system (Process Bag House) for handling dust / fines emissions to restrict to < 30 mg/Nm3.
Our working principle:
Clair Flash Dryers are used for drying a variety of wet cakes through a fully automatic process i.e. that require no handling or human involvement. The feed rate is adjusted automatically as per the variation in moisture content to ensure consistent product quality – every single time.
The principle of Flash Drying is to evaporate surface moisture instantaneously. The word “flash” is used, as the drying time is varies from a few milli seconds to a few seconds. This makes it ideal for drying heat sensitive, easily oxidized, materials that cannot be exposed to process conditions for extended periods.
Flash Dryers operate effectively on throughput rates varying from a few kilograms per hour up to several hundred tons per hour (based on the bulk density of the product). Our Flash Dryers are an efficient method of drying products such as slurries, pastes and sludge (most with back mixing), friable filter cakes, powders and granules.
Flash drying is a continuous process where the wet material to be dried is fluidized in hot air. Hot air is taking from the hot air generator or from the available existing heat source in the plant. Because the system has relatively low residence time and the moisture is flashed off, a significant amount of evaporative cooling takes place in the system. This allows higher inlet temperatures to be used than in many other dryers without unduly heating the product. Higher inlet temperatures also increase the overall dryer efficiency.
Unlike the descriptive name of most dryers such as rotary, spray or conveyor, flash drying refers to the mode of drying rather than the type of equipment. There is no single system configuration or component design for a flash drying system. The path of the gas stream may be a single long tube, camelback, loop design or series of cyclones, and each configuration offers unique characteristics.
Our flash dryer is energy efficient, requiring no intermediate material handling. These unique features make it an ideal replacement for conventional tray and rotary drying.
Exclusive features of our Flash Drying system:
3D model of our Flash Dryer
In one of the requirements, we provided flash dryer to reduce the 12% moisture present in slag to 1% for one of the renowned Cement manufacturers in India. Hot air at 350°C was generated for this process using a Hot Air Generator. Since HAG uses indigenous coal as fuel to generate hot air, which has a temperature range of up to 800°C, bleed air damper is provided to decrease the temperature of the hot air to 350°C. The dust arising after drying of wet slag was handled by the bag filter provided after the dryer tower.
The Slag (GGBS) is fed in to the dryer through a double flap valve which falls on to the Venturi provided in the dryer assembly. The GGBS particles are vented out through the top of the dryer assembly in to the cyclone filter assembly provided. The particles which are not vented due to the suction created by the fan are collected at the bottom of the dryer; the Cyclone & Bag filter material is transferred to Dry Slag Storage bin.
Please feel free to contact us for more details / our suggestions on drying systems.
Our Flash Dryer installation at one of the renowned Cement plants in India
