Prevent Bulk Material Flash Freezing in Hoppers and Chutes

Heaters in stalled on a chute.

A phenomena know as “flash freezing” occurs when aggregate material with trace amounts of absorbed water comes into contact with very cold metal surfaces, resulting in the aggregate instantaneously freezing.  The frozen material then instantly bonds to steel chutes or hoppers (which are at sub-freezing temperatures) causing an immediate, and possibly catastrophic, block in the hopper or chute.

Once this occurs, the cure is often a jack-hammer or other type of brute force method to clear the obstruction It's common for any coal mine, quarry, cement manufacturer, mining facility, or power plant to have a sledge or jack hammer on call for just this purpose. A far better approach is to prevent  sand, cement, ores, and mined products from freezing in the first place. 

The best solution are electric FRP heating panels. FRP heating panels are waterproof, dust tight, and vibration resistant electric heater panels that mount to the exterior walls of the hoppers and chutes. 

Specially designed for use in high shock and high vibration applications, their robust construction and corrosion resistance provides long life. 

Multiple heaters on a round hopper.

Because these atmospheres are normally dusty, and occasionally ignitable,  FRP panels are available with FM approval for use in hazardous areas. Furthermore, because hoppers, ducts, and chutes come in a never-ending variety of sizes and shapes, FPR panels are easily customized to conform in shapes and size to virtually application. 

If you work in a plant or facility where bulk material absorbs ambient moisture, and the possibility of freezing exists, you should learn more about FRP heating panels and their benefits they provide in reducing downtime, and more efficient operations. 

Electric Heating and Control Solutions for Power Generation

Hotfoil-EHS specializes in electric surface heating systems in power plants for fly ash hoppers on electrostatic precipitators or baghouses, coal and material handling systems, tanks, and pipes.

For more information, visit http://www.hotfoilehs.com.

Don't Let Frozen Aggregate Clog Your Process Equipment

FRP hopper heaters

FRP chute heater

Processing lines in coal mines, quarries, cement plants, mining facilities, and power plants have a special problem in very cold weather. The coal, sand, cement, ores, or other mined products they handle can freeze and cause equipment outages. The combination of trace moisture mixed with aggregate material, plus freezing temperatures, combine for major problems with conveyors, hoppers and chutes. When the aggregate hits the cold steel surface, it instantly freezes (flash freezing). The bond between the frozen aggregate and the steel wall is virtually unbreakable, and can cause long down-times with the equipment. Maintenance people have their own, time-tested curative solutions - torches and hammers - but installing preventative measures is clearly preferable.

FRP trough heater

The FRP heating panel, a waterproof, dust tight, and vibration resistant heater is an excellent preventative solution. FRP heaters are designed to be used in the high vibration, corrosive and dirty areas where they are installed. Available with FM approval for use in hazardous areas, they provide an easily customized panel that conforms to the shape and size needed to fit any chute or hopper. Additionally, they are lightweight, can be applied to flat or curved surfaces, and are very easy to install and maintain.

FRP trough heater

For more information on chute, conveyor, hopper or pipe heating, contact the experts at Hotfoil-EHS by visiting www.hotfoilehs.com or calling 609-588-0900.

Freeze Protection and Temperature Maintenance for Metallic & Non-Metallic Tanks and Vessels

Hotfoil ELP heating panel construction.

With winter around the corner, manufacturing plants need to consider the possibility of freezing or low process temperatures effecting outdoor storage tanks and transfer vessels. The most common approach is to install electric heating panels on the outer surface of these tanks and vessels to prevent the contents from freezing. Lower than normal ambient temperatures can also have negative effects on the flow of liquids for a given process. In these situations it is important to maintain liquids at a constant temperature. Electric heating panels are easy to install on tanks and vessels and provide the flexibility to heat a large area of the tank surface. They can also be used to target heat to specific areas on a tank.

Typical Hotfoil ELP
heating panel placement

Hotfoil ELP heating panels are suitable for installation on metallic tanks and vessels for freeze protection or process temperature maintenance up to 79°C/175°F. They incorporate flat foil resistive elements that are laminated by heat and pressure in a multi-layer fiberglass construction with epoxy resin. The resulting electric heater design is a semi-flexible panel that is waterproof and durable. They are used in a variety of heating applications spanning from freeze protection to process heating with exposure temperatures ranging from -40 F to +212 F.

ELP heating panels can be used on either vertical or horizontal tanks with diameters of 48" and above, with either metallic or non-metallic construction.  They can be used in dry, wet, or corrosive environments, are available in 120 and 240 volts, and are approved for hazardous and non-hazardous areas.

For more information, visit www.hotfoilehs.com or call 609.588.0900

Prevent Flash Freezing in Hygroscopic Aggregate, Mined or Quarried Materials with FRP Heaters

FRP heaters installed
(click for larger view)

When aggregate material with trace amounts of absorbed water comes into contact with very cold metal surfaces, the aggregate can instantaneously freeze, a phenomena know as “flash freezing”. When wet or frozen material encounters steel chutes or hoppers at sub-freezing temperatures, an instantaneous bond is formed. This bond causes immediate and often catastrophic blockage of the hopper and chutes. The bond and resultant blockage can be severe enough to require pneumatic drilling equipment to free up the system. Generally, this a problem for manufacturing and processing plants who utilize conveyors, chutes, and hoppers, such as coal mines, quarries, cement manufacturers, mining facilities, and power plants. Coal, sand, cement, ores, and mined products require a materials handling system that takes into consideration very cold weather and a strategy to prevent flash freezing.

FRP heaters installed
(click for larger view)

An excellent solution to this problem are electric FRP heating panels, a waterproof, dust tight, and vibration resistant heater. FRP heaters are designed to be used in the rugged landscapes where they are required and are very strong and corrosion resistant. They are available with FM approval for use in hazardous areas and are easily customized to conform in shapes and size to virtually and chute or hopper. Furthermore, they are lightweight, can be applied to flat or curved surfaces, and are very easy to install and maintain.

Flash Freeze Animation