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Welcome to the

“KERONE”

ESTABLISHED IN 1976

RADIO FREQUENCY HEATING In a radio frequency heating system the RF generator creates an alternating electric field between two electrodes. The material to be heated is conveyed between the electrodes , where an alternating energy field causes polar molecules in the material to continuously reorient them to face opposite electrodes much like the way bar magnets move to face opposite poles in an alternating magnetic field. Friction resulting from this molecular movement causes the material to rapidly heat throughout its entire mass. The illustration below depicts a radio frequency drying system with material between the electrodes. Polar molecules within the material are represented by the spheres with plus (+) and minus (-) signs connected by bars. The amount of heat generated in the product is determined by the frequency, the square of the applied voltage, dimensions of the material and its the dielectric loss factor which are essentially measures of the ease with which the material can be heated by radio frequency waves.

I N T R O D U C T I O N

DIAGRAM OF RF EQUIPMENT SCHEMATIC

A basic schematic of a Radio Frequency dryer is shown below. The dryer receives standard power (i.e. 480V, 60 Hz) through the Switchgear. In the Power Supply section, line voltage is stepped up to high voltage AC through a transformer and then changed to high voltage DC through rectifiers. In the Oscillator section, high voltage DC is changed to high frequency, high voltage RF energy and transmitted to the applicator or electrodes where it is applied to the work. All of this is controlled by a modern control system.

An RF Dryer works very much like a microwave oven which creates high frequency vibration of water molecules which thereby selectively heats materials containing water while other materials heat very little.

The key to effective application of RF energy for drying is the right applicator, or electrode design. Traditionally, heating was accomplished

by creating a uniform electric field between two parallel plates. This approach is capable of heating thicker materials uniformly because a high voltage gradient can be established in the material. However, it

does not work well for thin materials such as webs. In order to establish a high voltage gradient in a thin web material, the plates must be very

close together which can cause arcing between the plates.

For thin materials, the KERONE electrode design was developed. This design creates an electric field between alternating parallel rods that

gives a higher voltage gradient in the web for faster heating. A variation on this electrode design for thicker webs is the staggered KERONE

design. This allows for more uniform heating of thicker webs. This has also been used for thin beds of ceramic powders. As a general rule,

materials under 1/4” thick use the KERONE design, materials 1/4 ” - 1/2” use the staggered KERONE design, and materials over 1/2” use the

parallel plate design. In all of these electrode designs, the material can be either self-supporting or can be transported on a conveyor.

Materials have a major effect on the success of RF heating. Some materials heat very well and some do not heat well at all. The key measure of “heatability” is the loss factor of the material. The loss factor is a material property that determines how well the material absorbs the RF energy. If the material has a high loss factor, it

absorbs energy quickly and thus heats quickly. If a material has a low loss factor, it absorbs energy slowly and thus heats slowly. In general, polymers tend to have low

loss factors and thus do not heat well. Water, on the other hand, has a high loss factor so it heats rapidly. This is why RF lends itself to drying so well, it heats the

water quickly but does not heat most base materials.

It is important to remember every material reacts differently and loss factors (the ability to absorb RF energy) can change with frequency and temperature. A material

that does not absorb RF energy at room temperature might absorb the energy at higher temperatures. This is especially important in a composite product with a high loss factor material (RF heats rapidly) and low loss factor material (RF heats slowly).

As the high loss factor material is heated by the RF energy, it will heat up the low loss factor material through normal conduction. If this heat raises the temperature of the low loss factor material to where it now absorbs RF energy, both products are heated and could be overheated. In rare cases, this can lead to a runaway situation where as the temperature increases, it absorbs more energy, which increases the temperature, which increases the energy absorbed, and it continues until the material overheats.

In most cases, the product can be heated faster than the solvent can be removed so the heating rate must be scaled back to get the

right balance of heat transfer and mass transfer. If the heat transfer rate is too high, steam will be generated which can

damage the product.

The complexity of the interaction between materials and the RF field is why it is critical to consult with an expert in RF drying and

conduct trials on your product.

APPLICATIONS

• Conventional mode of Drying Textiles after they have been dyed is a slow process. Textile industries can increase Throughput and fill orders more prominently using Radio Frequency (RF) Dryers. RF system has capability to accelerate the drying process and shorten production time. RF drying offers High Volume, High speed and High quality drying which is what exactly needed in textile industries. As wet garments of Acrylic, Cotton, Nylon and Polyester Blends pass through the drying chamber , the radio waves vibrates the contained Water molecules million times per second, vaporizing them. Ventilator Fans are used to remove damp air from the Drying Chamber.

The dryer system comprises the 125kW industrial high frequency generator in conjunction with a drying chamber incorporating an electrode applicator and air extraction system. The equipment is suitable for drying most types of Fabric which have had prior mechanical moisture extraction in either, cone, muff, bump or loose stock form. Many types of fibcriccan be dried. The machine incorporates a modular polypropylene conveyor band and conveyor system.

• Conventional mode of Drying Textiles after they have been dyed is a slow process. Textile industries can increase Throughput and fill orders more prominently using Radio Frequency (RF) Dryers. RF system has capability to accelerate the drying process and shorten production time. RF drying offers High Volume, High speed and High quality drying which is what exactly needed in textile industries. As wet garments of Acrylic, Cotton, Nylon and Polyester Blends pass through the drying chamber , the radio waves vibrates the contained Water molecules million times per second, vaporizing them. Ventilator Fans are used to remove damp air from the Drying Chamber.

• The dryer system comprises the 125kW industrial high frequency generator in conjunction with a drying chamber incorporating an electrode applicator and air extraction system. The equipment is suitable for drying most types of fibres which have had prior mechanical moisture extraction in either, cone, muff, bump or loose stock form. Many types of fibre can be dried. The machine incorporates a modular polypropylene conveyor band and conveyor system.

• Because of the RF waves concentrate in the wettest, densest portion of the garments. RF drying has a leveling effect that practically eliminates any problems of uneven shrinkage and over drying. The RF drying times depend on the type of fabric, the percentage of moisture in the fabric going in to the dryer, and the degree of dryness desired.

ONLINE RADIO FREQUENCY (RF) DRYER

ADVANTAGES:

The major advantage is that it gives thorough, consistent drying in less time and also occupies less space. In addition to these following advantages are prominent: •Faster Drying

•Faster Production

•Increased Labor Production

•Less work in progress

•Energy Saving

•Less Down Time

•Lower Maintenance

•Space savings

FEATURES: Energy applied by radio waves at a frequency of 40.68 MHz. Volumetric heating keeps the temperature low and uniform throughout the web to prevent overheating. BARRIERS TO MARKET ACCEPTANCE price risk of failure benefits not understood priorities not on benefits of new technology lack of technology awareness

TEXTILES INDUSTIRIES

1.ONLINE TEXTILE RF DRYERS • Conventional mode of Drying Textiles after they have been dyed is a slow process. Textile

industries can increase Throughput and fill orders more prominently using Radio Frequency (RF) Dryers. RF system has capability to accelerate the drying process and shorten production time. RF drying offers High Volume, High speed and High quality drying which is what exactly needed in textile industries. As wet garments of Acrylic, Cotton, Nylon and Polyester Blends pass through the drying chamber , the radio waves vibrates the contained Water molecules million times per second, vaporizing them. Ventilator Fans are used to remove damp air from the Drying Chamber.

• The dryer system comprises the 125kW industrial high frequency generator in conjunction with a drying chamber incorporating an electrode applicator and air extraction system. The equipment is suitable for drying most types of fibres which have had prior mechanical moisture extraction in either, cone, muff, bump or loose stock form. Many types of fibre can be dried. The machine incorporates a modular polypropylene conveyor band and conveyor system.

2.DRYER FOR NONWOVEN WEBS The RF Web Dryer rapidly removes moisture from the web at low temperatures and prevents the migration of coating solids caused by conventional drying which increases web strength and product quality.

This dryer eliminates the need for accumulation rollers required by festooned convection and infrared type dryers and saves floor space by generally requiring one-fifth of the floor space needed for hot-air and IR dryers as well as lowering maintenance costs.

Features: • Volumetric heating keeps tEnergy applied by radio waves at a frequency of 40.68 MHz. • he temperature low and uniform throughout the web to prevent overheating.

FOOD PROCESSING INDUSTRIES

1.POST-BAKING DRYER The combination of conventional oven heating with RF heating in the final stage of the drying process is an extremely

efficient way to produce many types of baked products, and it's easy to do. Radio frequency post-baking dryers are generally supplied as stand-alone turnkey systems, which can be ordered for retrofit to an existing or new oven line.

RF post-baking dryers automatically adjust power to respond to varying moisture loads resulting from oven burner failures, minor dough moisture and sheet thickness variations. A pre-adjustment assures that the product is still produced within moisture specifications despite varying incoming moisture levels

Benefits Increased Throughput: Up to 30% increase for crackers and often up to 40% for cookies. Elimination of Checking: By greatly reducing the moisture variation throughout the thickness of the product, checking caused by differential shrinkage is eliminated. Excellent Control of Final Moisture Content: Final moisture is controlled to approximately +/-0.25%. Independent Color Control: Since moisture is controlled in the RF dryer, color development in the oven can be done without concern for final moisture content

ADVANCED BOOKBINDER DRYER

In-Line Radio Frequency Drying System for Sewn and Perfect-Bound Books Using Water-based Adhesives

Features: 1.Compact one-piece design saves floor space. 2.High performance electrode arrays resist belt abrasion. 3.Automatic mechanical belt tracking. 4.Adjustable for books .5" (13mm) to 3.15" (80mm) thick. 5.Opposite-hand dryer configuration is available for dual installations handled by one operator. 6.Does not radiate heat or affect the working environment. Custom-design automated glue drying systems are also available for new and existing installations. 1.Fast and easy belt replacement. 2.Four-zone drying applicator for precise control of glue temperature

Benefits: •Use water-based glue at high production speeds. •Bind continuously in-line without handling and stacking before trimming. •Binder-to-trimmer time is reduced. Eliminates trimmer blade fouling. •Glued area of the book is selectively heated and dried, while dry areas receive little or no heating. Minimum cooling is required. •Glue charring, blistering and skinning-over is eliminated. •Requires a fraction of the floor space of conventional dryers. •Efficient use of energy. RF power is instant-on-off. •Improved book quality, flexibility and recyclability.

CHEMICAL INDUSTRY

1.VERTICAL RADIO FREQUENCY WEB DRYERS FOR ON-PRESS DRYING OF WATER BASED COATINGS, ADHESIVES AND INKS

Benefits: •Wet areas on the web are selectively heated and dried, while dry areas absorb little or no energy. •Aqueous materials can be dried in the shortest line length to production speed of any drying method known. •Instant-on R.F. power eliminates start-up delays. •Requires a fraction of the floor space of conventional dryers. •Highest productivity is achieved with aqueous materials. Solvent emission and disposal problems are eliminated. •Energy saving. The electrical power consumed by the dryer automatically adjusts to the amount of water present on the web.

Features: •Convenient access doors facilitate web threading. •Waste heat from the RF generator is channeled through the applicator to scavenge moisture released by dryer. •Solid State controller provides soft-start and maintains power at preselected level. •Optional auto-threading system is available to minimize make-ready time.

BULK SOLIDS

This drying system uniformly heats filter cake material throughout the thickness of the product depth and rapidly removes the water without overheating, at a fraction of the time and expense associated with conventional dryers.

BENEFITS: 1.PRECISE MOISTURE CONTROL: Selectively heats products where the moisture content is the highest. The product output will be uniform in moisture content throughout, regardless of the non-uniformity going in. 2.INCREASES PRODUCTION THROUGHPUT: Product throughput on many applications can be increased 50% to 100%. 3.MINIMIZE DRYING TIMES: Rapid volumetric heating eliminates the long dwell time required by conventional heating and is a suitable replacement for tumble-, spray-, tray-, spin flash-, and belt/tunnel dryers. 4.OTHER BENEFITS: Energy savings and floor space savings. Typically requires one-fifth the floor space of conventional drying systems.