TEC Square’s model D spray dryer is a design based on years of hands-on experience with optimizing plants and installing world-class equipment. We believe in a design that is flexible in set-up and allows for additional options at a later stage.
Principle of Operation for a Spray Dryer
The principle of operation of a spray dryer is rather simple: A liquid stream is pumped into a hot chamber, where the solid part will separate from water by evaporation. The solid part will find its way down into the tower, and ends up in a secondary process, where we post-dry, cool and sieve the powder. Next, we store the final product in tote-bins, big-bags, or silos. At the other side of the operation, the evaporated water will go through a secondary treatment of filtration to recuperate any solids, after which, the system will send the moist air to an exhaust on the roof.
In a Spray Dryer we distinguish the following sub-systems:
- Hot air system: To dry a concentrated liquid we use hot air of at least 180°C. We use two different solutions for this purpose. For cost-effective solution, we use high pressure steam heaters, as these units are relatively inexpensive and easy to maintain. For high-end solutions, we mainly use gas-fired heaters.
- Pulverization: At the top of the tower we spray the concentrated liquid into a hot air stream in the form of tiny droplets. We use a multiple-nozzle pressure technology for the best results.
- Drying chamber: TEC Square uses turbulent drying conditions, to ensure the best possible product quality. We believe that the best drying conditions will be in relatively small chambers. The smaller the chamber, the lower the so-called “refresh rate”. As a consequence, the powder will have less time in the spray dryer, and the quality of the product will be higher.
- Powder Collection: We collect the powder at the bottom of the spray dryer. From here we feed the powder to an after-dryer and after-cooler to obtain the right moisture and temperature for storage. For some products there is also a sieving step.
- Air Treatment: The exhaust air exits from the tower at the top. Fine powder, which is normally present in the exhaust air, will be separated in a big-filter. Sometimes, (and this might be different for every application) we use cyclones for this purpose as well. The filtered moist air will then go to an exhaust on the roof.
Advantages of a TEC Square Spray Dryer
The process has several advantages over other processes:
- Simplicity: TEC Square designs its spray dryer plants simple. We believe that a good design should be functional and straight forward. We do not complicate a system if this is not needed.
- Capacity: Spray dryers can be delivered for small capacities (e.g. pilot plant drying) to very large capacities (10 Ton per hour is not an exception).
- Product characteristics: A spray dryer allows you to control and influence powder qualities with precision. Particle size, moisture content, color and other specific properties can be set, irrespective of dryer capacity.
- Small Footprint: We design plants in a very compact way. This approach delivers a lot of benefits to the operation:
- Supervision becomes easier
- Building costs and installation costs are less
Special TEC Square Spray Dryer Solutions
Our experience in designing and installing spray dryers is mainly gained on the manufacturing side of the business. All our key engineers have experience in running, maintaining or optimizing food multiple production plants over a period of many years. We developed extensive knowledge that is based on experience. And this in turn provides us with an insight in operational solutions that can make a difference in the operation of any spray drying plant.
For certain processes we provide special executions or technologies. We highlight in the section below some of these solutions. For more information please contact us directly.
Integrated solutions from the high-concentrator
The quality of a product remains high if the overall process time is kept as short as possible. For this reason, we provide integrated solutions with the high concentrator, avoiding investment in additional equipment as well.
For certain processes, we provide de-humidification. We work with chillers as well as desiccant-based solutions
Heat Recuperation on exhaust air
For high-end solutions, we provide energy recuperation on the exhaust air. In our quest to reuse energy to a maximum we do not shy away from unconventional methods.
We provide two different solutions for integrated agglomeration:
High-TS Spray Dryer
TEC Square provides solutions for additional capacity on a specific spray dryer by increasing the concentration of the liquid product.
We use a Rototherm-E for this purpose, as product losses are kept to a minimum. Often the hourly capacity can be increased by 10-20%.
Spray Dryer weekend storage mode
In some climates the humidity plays a huge part in the operation of a plant. For hygroscopic products this will result in the need to clean the spray dryer after a prolonged stop. We provide special solutions to “store” the equipment over a certain time.
Cleaning / CIP
TEC Square provides special solutions for CIP and/or cleaning. We aim to: