Standard Fluid Bed Drying and Cooling
VENTILEX fluid bed dryers offer significant advantages over rotary drum dryers. This has led to the predominant use of fluid bed dryers in new dry mortar plants worldwide. In addition, VENTILEX is often called upon to replace rotary drum dryers in existing mortar and aggregate plants. Some of the reasons for this are:
· The drying air is more evenly distributed over the product in the VENTILEX fluid bed dryer than in a rotary dryer. Therefore, the temperature of the dried product can remain constant. This allows better control of the drying air temperature and the product temperature. Fluctuations in the amount and moisture of the product do not adversely affect the VENTILEX fluid bed dryer.
· The dryer and cooler are integrated in a unitary piece of equipment. A rotary drum dryer will need a separate cooler for the product, increasing the cost by 30% to 60%.
· Due to the multi-point PLC temperature controls, the exhaust air temperature can be lowered. As a result, the energy costs are lower than for a rotary dryer and most other conventional high-frequency vibrating or static fluid bed dryers.
· Energy usage on a VENTILEX fluid bed dryer is much lower than energy consumption on a rotary drum dryer (proven value at least – 30% and in many cases 60%). The VENTILEX fluid bed has far better control over the final temperature of the product and the air is in cross flow with the product instead of co- or counter-current flow. The exhaust from the cooler area can be recycled to the dryer area so that all energy in the product is reclaimed in the dryer.
· Multi-stage PLC controls make sure that the product temperature is not higher than necessary, so the cooling section can be economized.
· The VENTILEX fluid bed can handle wider varieties of grain [product] size and moisture content than rotary dryers.
Due to low-frequency/high-amplitude plug flow design, the VENTILEX fluid bed requires less maintenance and has low consumption of wear parts than
all high frequency vibrating Fluid Bed Dryers.Design Features of the VENTILEX Fluid Bed Dryer:
· Direct product contact parts of the fluid bed are manufactured in stainless steel, no corrosion even with use of fuel oil (sulphur).
· Unlike other fluid bed dryers, the VENTILEX fluid bed can handle an abrasive product without excessive wear. This is due to the high-amplitude, low-frequency fluidized conveyance.
· Product inlet and product outlet are provided with serviceable wear plates [AR-400].
· Exact control of product end moisture is possible with variations in inlet moisture content.
· No need to clean out stones or larger particles like in static fluid beds and many vibrating fluid bed dryers. The high amplitude motion of the dryer transports these as well.
· The burner housing and the undercase of the dryer are built in high temperature resistant steel instead of stainless steel or carbon steel [we use 16MO3].
· The construction of the dryer is designed to avoid problems associated with thermal expansion. Construction details include:
- Hatches are round to avoid cracks.
- The bedplate is mounted in such a way that the plate can move freely.
- The undercase is mounted with a slide construction to the frame to allow for thermal expansion.
- No sharp corners or edges. These are places where cracks start, especially with vibrating units
- Strengthening strips are mounted in such way that the dryer can expand.
Standard Drying | Recirculation Drying | Evaporative Cooling |Ventura 130
