Lamina Drying & Cooling

Tobacco machinery sales

Super Lightweight Rotary Dryer (LWD)

The Garbuio Super Lightweight Rotary Dryer overcomes the disadvantages of earlier types of rotary dryer. Light Weight Dryer

Responsive Advanced Technology
Advances in manufacturing techniques including laser welding have allowed the construction of a lightweight shell and lifting paddles. These are manufactured from thin stainless steel sheet material laser welded together and then hydraulically inflated to provide steam and condensate flow passages. The lightweight shell is specially supported in such a way that the weight of the shell is evenly distributed around the circumference of the track rings. The dryer is designed to operate with a relatively low product loading, thus enabling drying to take place with a short process dwell time. This gives considerable advantages in the ease with which the dryer is controlled, since small changes in process conditions can be made with virtually immediate effect. For the same reason, over-dried product at the start and finish of a batch is minimised. The use of minimal contra-flow process air ensures that final product fill value is maximised, together with the energy efficiency of the process. The high humidity process air condenses on and warms the relatively cool product entering the dryer. This enhances the product fill value and prevents over-drying of the tobacco surfaces or ‘Case-Hardening’. With this system, additional pre-processing equipment such as a steaming tunnel is unnecessary and is not required. Warm air is introduced into the exhaust ducting to ensure that deposits of wet dust do not build up in the duct and give rise to cleaning and maintenance problems.

EVA

EVA drying technology is well established and has been proven over many years in a number of International Tobacco groups. EVA

High performance drying versatility
EVA is a closed loop, low Oxygen system which uses superheated steam as the drying medium. The low Oxygen allows relatively high process temperatures to be used without the risk of oxidising or changing the nature of the tobacco. The rapid drying effect, which is due to the high drying gas temperature and its composition, results in enhanced fill value. The pressure inside the dryer is controlled to be slightly positive, thus minimising any inward or outward leakage. This enables low Oxygen levels to be maintained with relatively small amounts of steam injection. One of the major advantages of the EVA process is that product can be fed directly from the cutter to the dryer without the need for any additional pre-process equipment for conditioning or heating the product. The soft cutting features of the Garbuio SD cutters make this machine particularly suitable for directly feeding the EVA dryer. Product leaving the EVA dryer is immediately lifted and pneumatically conveyed in a classifying pneumatic transport system. This performs the dual function of removing any unwanted heavy particles, and rapidly cools the tobacco close to ambient conditions in order to maintain the fill value achieved in the EVA dryer. The EVA process exhaust passes through an air blast condenser which converts it to a cool, biodegradable liquid which can be simply disposed of in the normal sewer system. The small quantities of non-condensables remaining in the exhaust present little problem since they are cool, but for critical applications in sensitive locations these are easily treated by additional equipment. Energy efficiency of the EVA dryer is high, with a specially designed gas or oil fired process heater. Hot gases from the burner are recirculated over a tubular heat exchanger, resulting in relatively low temperatures for those parts in contact with the process gas. This minimises potential degradation of volatiles present in the process gas, which might otherwise affect the taste of the product. For even higher thermal efficiencies, combustion air preheat can be offered for the larger sizes of EVA dryers. Depending on the type of tobacco being processed, optional clean-in-place features can be provided to clean critical areas of the dryer internals. In any case, the EVA is designed to provide excellent access for internal cleaning and inspection of the product infeed and drying column.

Annular Dryer

Responsive Drying Technology
The Garbuio Annular Dryer is well established for a wide variety of applications, including cut lamina, cut expanded stems, cloves and snuff. The unique form of construction, with the cylinder supported on a central shaft carried by trunnion bearings, eliminates the need for track rings, support rolls and their associated maintenance. The use of one drying cylinder within a larger outer cylinder provides an increased heated surface area in a relatively compact space envelope. The Annular Dryer can be provided with suppressed contra-flow process air, or alternatively in-line (co-current) air according to the process requirements. It is suitable for conventional steam heating, or High Pressure Hot Water (HPHW) where extremely rapid control is required with a wide range of evaporative duties. The short distances through which the tobacco cascades from the outer cylinder to the inner and back result in very low degradation and enhanced fill value. This is further contributed to by the short product transit times though the dryer, which also facilitate excellent control of final product moisture.

XL rotary dryer

The Garbuio XL rotary dryer is a well proven system which has gained acceptance throughout the industry.

Versatile, efficient and well proven
In its steam heated form, the dryer shell is comprised of steam tubes connected together by flat strips of steel welded to the outside of the tubes. Thus the only welds subject to steam pressure are those at the ends of the tubes. The dryer is suitable for steam pressures up to 10 bar(g) or process temperatures up to 180 C if required. In the gas/oil heated XL dryer, hot flue gases are circulated around the outside of a thin stainless steel cylinder by high volume centrifugal fans. These flue gases do not come into contact with the product, but transfer their heat to the tobacco through the 3 mm thick walls of the cylinder and paddles. The gas heated version offers a much wider turn-down capability than any steam heated dryer, and is also able to process both blond and black tobaccos. If required, this dryer may be configured to provide a torrefaction effect for black tobaccos. The use of minimal contra-flow process air ensures that final product fill value is maximised, together with the energy efficiency of the process. The high humidity process air condenses on and warms the relatively cool product entering the dryer. This enhances the product fill value and prevents over-drying of the tobacco surfaces or ‘Case-Hardening’. With this system, additional pre-processing equipment such as a steaming tunnel is unnecessary and is not required. Fast acting accurate moisture control is provided by means of a finely atomised modulating water spray at the delivery end of the dryer. This provides a small additional moisture loading which is automatically modulated in order to correct small deviations from target moisture. Over-dried product at the start and finish of a batch is minimised by a special run-in and runout sequence control. This ramps the cylinder temperature set point and process air flow to avoid over or under drying. During runout, the process airflow direction is reversed to hasten the tobacco out of the dryer.

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Super Lightweight Rotary Dryer (LWD)

  • Lightweight shell construction
  • Fast process transit time
  • Excellent moisture control
  • Minimal off-spec tobacco
  • High humidity process maximises fill value

EVA

  • Well proven cost effective expansion process
  • Maximises fill value
  • Suitable for both lamina and stem
  • No pre-processing required
  • Simple and compact
  • Energy efficient
  • Simple, effective exhaust treatment
  • Minimal off-spec tobacco

Annular Dryer

  • Low degradation
  • Enhanced fill value
  • Steam or High Pressure Hot Water heating
  • Short process time and rapid control response
  • Suppressed contra-airflow
  • Alternative in-line (co-current) airflow
  • No track rings or support rollers
  • For Cut Lamina, Cut Expanded Stem, Cloves, Snuff

XL rotary dryer

  • Simple shell construction
  • Excellent moisture control
  • Minimal off-spec tobacco
  • High humidity process maximises fill value
  • Available in both steam and indirect gas heated versions
  • Gas heated version provides torrefaction capability if required