Rotary dryers are ideally suited to handling a wide range of particle sizes, or where material needs to be dried at a high temperature over a long period of time.
Energy efficiency and low emissions are top priorities for our design engineers. Heat recovery – utilising heat from the exhaust system – is an important focus, as is the development of highly efficient seals. As well as minimising environmental emissions, our high quality sealing systems create more closely controlled processing conditions resulting in more efficient, cost-effective production.
- Robust, durable dryer design with a long service life
- A wide range of process temperatures can be achieved
- Waste heat recovery can be included to enable energy saving
- Smaller units are frame-mounted to speed installation
- Installation is carried out in just a few days, even with larger models
- Highest quality materials used in construction
- Suitable for indoor and outdoor installation
- Noise emissions matched to local regulations or site requirements
Directly heated rotary dryers are typically used for inorganic chemicals, fertilisers, sand and food substances. Each system we supply is designed to meet specific client requirements.
With directly heated dryers, wet material is fed into a revolving drum through which hot gases are blown. The hot gases can either be fed in the same direction as the wet material (co-current operation), or in the opposite direction to the material (counter-current operation). Internal lifting flights cause the material to shower through the air stream. This promotes better heat transfer and efficient drying, which means faster processing and lower energy usage.
Steam tube systems are used for drying a range of materials from fine powders to large particulate solids and sludges. Typical applications include spent grains, activated carbon, powdered plastics, soybean, corn fibre, germ, fish meal, bio-solids, industrial and municipal sludges, and TA and PTA.
The steam tube rotary dryer consists of a horizontal rotating shell fitted with a large number of heating tubes. The saturated steam admitted to the tubes maintains the necessary drying temperature and the product is tumbled around the hot tubes with the moisture driven off as vapour.
Depending on the downstream processing requirements, an air cooler or water cooler can be supplied with the drying system.
With an air cooler the material is fed into a rotating shell similar to a rotary dryer, then lifted and cascaded by the internal flights through the cooling air stream. Counter-current flow enables the product temperature to approach closely that of the ambient air stream. For added efficiency, the exhausted air from the cooler can be fed into preceding dryer stages.
With a water cooler, water is normally applied externally to the shell by spray pipes. The cold cylinder walls in turn cool the material inside. A shroud containing the water pipes encloses the centre portion of the shell.
A cooling section is often incorporated at the end of an indirectly heated rotary dryer, a single shell serving both operations.