Pulse combustion flash dryer

FIGURE 23.15 Pulse combustion flash dryer developed by Novadyne, Ltd, Canada. 

Figure 14.8 Flowsheets of (a) the pulse combustion flash dryer and (b) pulse combustion dryer. (Courtesy of Novadyne Ltd., Hastings, Ontario.)...

Table 14.2 Test Data for Wood Waste Dried in a Pulse Combustion Flash Dryer...

Buchkowski A, Kitchen J. Pulse combustion flash dryer. Technical Report. Hastings, Canada Novadyne Ltd, 1995. 

Buchkowski AG. The development of a pulse combustion flash dryer. Proc. Combustion 96, Ottawa, Canada, 1996. 

Tab. 2.4 Test data for wood waste dried in a pulse combustion flash dryer (courtesy of Novadyne, Ltd, Hastings, ON, Canada).

Use of superheated steam in direct dryers Increased use of indirect (conduction) heating Use of combined (or integrated) heat transfer modes Use of volumetric heating (microwave [MW]/radio-frequency [RF] fields) in specialized situations Use of two-stage (or multistage) dryers Use of intermittent heat transfer Use of novel combnstion technologies (e.g., pulse combustion for flash drying)... 

Figure 23.15 shows the flow diagram of one prototype pulse combustion dryer designed by Novadyne Ltd (Canada) (Kudra and Mujumdar, 1995, 2002 Kudra et al., 2003). In the flash dryer configuration, the unit consists of a pulse combustor, a pneumatic duct that extends from the tailpipe of the pulse combustor, and devices for materials feed and discharge. The pulse combustor uses a self-actuated flapper valve, and its operating frequency is about 70 Hz. The rated capacity of the combustor equal to 300 kW offers an evaporative capacity of about 275 kg/h of water. Wet particulate materials such as sawdust, hog fuel, corn fibers, or spent coffee grounds are injected directly into the tailpipe... 

Kudra T, Pallai E, Bartczak Z, Peter M. Drying of paste-like materials in screw-type spouted bed and spin-flash dryers. Drying Technology 7(3) 583-598, 1989. Kudra T, Buchkowski AG, Kitchen JA. Pulse combustion drying of white pine. Proc. 4th lUFRO Inti. Wood Drying Conf., Rotorua, New Zealand, 1994, pp 396-403. 

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