Dedert Spray Dryers
Dedert has pioneered the development of a new high speed rotary atomizer for the chemical and food industries. Dedert's new range of spray dryers, built around the innovative, patented atomizer, adds to its expansive portfolio of leading evaporation and drying technologies and enhances Dedert's reputation for quality and performance.
The new design, based on magnetic bearing technology, eliminates the need for high maintenance gear drives, bearings, shafts, oil lubrication and cooling systems, providing unparalleled flexibility for the most demanding applications. The cutting edge rotary atomizer is a robust mechanical and compact design, which offers lower maintenance and higher reliability over conventional rotary technology. The atomizer is provided complete with variable speed drive and a fully automated PLC-based utility and control system.
Key features of the rotary atomizer:
- Built around magnetic bearing technology.
- Capable of 16,000rpm, designed to run below first critical speed.
- High capacity units available up to 350hp.
- Immediately compatible with existing installations.
- Complete strategic units held in storage in Chicago, IL.
- Easy to maintain and service.
Spray drying is the process of atomizing a liquid feed in either a slurry or solution form into fine droplets. Heated drying gas then converts the atomized particles into a dry powder by evaporation of the liquid phase. The atomization process can be accomplished with a rotary wheel coupled to a high speed drive or a spray nozzle atomizing system. Both methods offer advantages for specific product properties, including particle size and distribution, density, shape and morphology, and dispersibility.
Rotary atomization is the most flexible method of controlling feed rate and dryer operation while maintaining the required dry product specifications. Combined with a specially designed atomizing wheel and liquid feed distributor, the rotary atomizer can accommodate a broad range of liquid feeds, including abrasive products.
The new spray dryer is enhanced with an innovative gas disperser to ensure optimum contact between the heated drying gas and atomized spray cloud, and thereby improve dryer performance and efficiency.
A proprietary explosion vent door protection system for new and existing installations meets the latest code requirements and is flush mounted, providing a sanitary tight seal design.
The spray drying systems are supplied with the most efficient product separation and gas cleaning technology available. High efficiency cyclones, bag filters or wet scrubbers are incorporated for pollution control to meet the most rigid plant emission requirements. Fully integrated thermal oxidation systems can also be included for removal of VOC and other emissions.
Energy integration and heat recovery offers the most energy efficient system. Combined with Dedert evaporation systems, Dedert can provide a complete liquid concentration to dry product plant for the food and chemical industries.
Dedert is well placed to offer spray dryer replacement, retrofits, upgrades and audits; we offer a complimentary review of existing spray drying plants.
Dedert spray dryers are used in the food industry for products such as: ingredients, spices, sweeteners, flavors, botanicals, nutraceuticals, vitamins, minerals, emulsions, flavors, proteins, yeast, starches and sugars.
For the chemical industry, Dedert spray dryers are used for products such as: specialty chemicals, inorganic chemicals, minerals, pigments and dyestuffs, and ceramics.
Single and Multi-Stage Spray Dryers
The spray drying system can be in single or multiple stages with integrated fluid bed processing. The fluid bed system is typically provided for post drying, agglomeration, conditioning and cooling. Dedert’s spray drying systems are available from pilot scale up to 20,000 kg/hr evaporation.
Single-Stage Spray Dryers
The single-stage spray dryer is the most common and flexible solution for drying a full range of products in the food and chemical industries. The process converts a liquid feed into a dry, free-flowing powder by atomization into small droplets. The main methods of atomization are centrifugal rotary wheel or hydraulic high-pressure nozzles. The final product is produced with an average particle size range of 25 -100 micron.
Dedert’s spray dryers are equipped with a proprietary hot gas distributor, which ensures optimum contact with the drying medium in the drying chamber. The liquid feed is dried to a fine powder in the drying chamber and discharged from the cone bottom or conveyed with the exhaust air to a primary separator, either cyclones or a dust filter. The drying configuration is primarily co-current but can be offered in other configurations depending on the specific application. For heat sensitive and difficult-to-dry products, integrated cooling for the chamber, roof and hot gas distributor are provided.
Multi-Stage Spray Dryers
Multi-stage spray dryers are used on products which are hygroscopic, sticky and require extended residence time at lower drying temperatures.
Dedert’s multi-stage spray dryers include the following equipment/features:
- Rotary or nozzle atomization with adjustable design for optimal contact of atomized droplet and powder fines
- Production of non-dusty, free-flowing products
- Powder is easily dispersible and re-wetable
- Lower bulk density and particle size from 100 – 500 microns
- Agglomeration using fines recycle and re-introduction to an atomization zone and/or Fluid Bed
- Integrated Fluid Bed design to handle more difficult products and improve drying efficiency
- External Fluid Bed design for final drying, processing and powder cooling
- Sanitary, hygienic design available for infant formula, food ingredients and pharmaceutical applications
- Complete ‘Clean In Place’ systems available
- Dust explosion protection to latest NFPA, Atex, VDI requirements
- Direct and indirect heating using a wide range of heat sources
- Proprietary 2-stage cyclone discharge systems for improved powder collection
- Wet ‘Clean In Place’ dust collector available
- Air de-humidification systems available
- Energy recovery