With a wide range of end-product specifications and customer requirements, SPX has developed an extensive range of processing options to suit each particular customer requirement. In general, processing can be divided into three main stages:
- Liquid milk processing
Liquid milk processing
SPX FLOW's vast range of expertise in this area is described in the "Liquid" section of the dairy capability.
SPX FLOW has specialist capability in evaporation technologies and is able to offer a wide range of process options to suit particular customer requirements.
- We have an extensive reference list of over 3,000 evaporation systems worldwide
- Experience covers a wide range of food, dairy and chemical liquids
- The range of evaporator options includes tubular and plate types
- Falling film, rising film, rising/falling film and forced circulation types are available, with optional mechanical vapour recompression or thermal vapour recompression to minimise energy usage
- This broad capability enables the optimum solution to be selected in terms of running economy, product quality and capital cost
SPX FLOW has specialist capability in drying technologies and is able to offer a wide range of drying equipment to suit the particular needs of the dairy industry.
- Single-stage spray drying
- Two-stage spray drying with fluid bed
- Three-stage spray drying with integrated and external fluid bed
- Cooling and powder agglomeration
Spray drying is a continuous operation during which milk can be converted into a free-flowing powder in a few seconds. Because of the very short residence time, the spray drying method is applicable to heat-sensitive products which have to meet very high powder quality demands. Most dairy and food products require special heat conditions in order to retain valuable nutrients and flavors.
One of the latest designs of flexible spray dryer for high-quality powder production is the spray dryer with integrated fluid bed. It consists of a spray dryer with a static fluid bed integrated in the conical bottom of the drying chamber.
Drying is achieved by spraying the feed product into the hot drying air in the drying chamber. The hot air provides the necessary heat for evaporation, which takes place almost instantaneously due to the very large liquid surface created by the atomization.
The resulting powder is taken out at the bottom of the chamber and conveyed for further handling, storage and packing. The spent drying air containing powder is cleaned in highly efficient cyclones. In many cases, the air is further cleaned in a bag filter or a wet scrubber.
The energy contained in the spent drying air can be used for preheating the incoming air, the feed to the spray dryer, or for other heating purposes.
After the drying process, the powder can be cooled in an external fluid bed or in a pneumatic cooling/conveying system. The cooled powder is ready for packing or it can be stored in silos.
Spray bed drying
SPX FLOW has developed the spray bed dryer, which produces powders that are dust-free, agglomerated, easily dispersible and free-flowing. The spray bed dryer also offers other important plant benefits such as continuous, fully-automated operation, low energy consumption, gentle product treatment and attractive capital investment.
The spray bed dryer is suitable for production of agglomerates in larger sizes and with fewer fine particles than single-stage spray dried powder. The particles are uniform because their size can be controlled by means of the air velocity in the fluid bed.
By adjusting design and process parameters it is possible to influence the structure if the agglomerates and control bulk density and dispersibility.
Fluid bed technology
Ourfluid bed dryer ensures good heat transfer coefficients and avoids degradation reactions in heat-sensitive products.
Intimate air-to-product contact ensures good heat transfer. The principle of cooling together with further processing can be particularly applicable after spray drying.
Dust-free and instantized products can be obtained by agglomeration and controlled to give optimum particle size distribution. Wettability, dispersibility and solubility properties can be improved using this technique.
Process Diagrams and Benefits
Skimmed Milk Process
Whole Milk Process
- SPX FLOW's global experience as a supplier of processing technology and equipment for dairy products is a key factor in our ability to deliver cost-effective solutions tailored to individual customer requirements.
- Ourwide range of plate and tubular evaporators allow the optimum processing conditions to be selected to ensure consistent, high quality product.
- Spray bed drying gives improved agglomeration of powders and results in less deposits and narrower particle size distribution.
- Fluid bed systems have separate drying regions and directional air flow which result in improved performance.
- To minimise the need for cleaning, APV's plants can be supplied with an efficient high pressure air broom which reduces powder deposits in the dryer,thereby achieving longer run times.
- We offer an enormous range of resources to the dairy industry in process engineering, equipment manufacturing, project management - for both large and small projects - and world-class development facilities.