Factors To Consider While Choosing Right Rotary Dryer

Factors To Consider While Choosing Right Rotary Dryer

For optimum efficiency and operation, how a fuel dryer operates in conjunction with other equipment in the facility must be considered.

Energy Efficiency And Heat Recovery

Low temperature dryers, such as conveyor dryers, can best take advantage of heat recovery opportunities. Drying of biomass under vacuum reduces the boiling point of the water in the wet material and so reduces the temperature required for drying, increasing opportunities for heat recovery. Vacuum dryers generally use hot water as the heat source and so heat can be more easily transferred to the dryer from process equipment

Environmental Emmissions

Volatile organic compounds, such as terpenes and other wood oils, are exhausted from hog fuel dryers and must be monitored. In addition, particulate emissions from the dryer may need to be reduced by utilizing filtration or other type of particulate removal system. Direct-fired rotary dryer have greater emission of VOCs and particulates than indirectfired dryers. Conveyor dryers have lower emissions of VOCs and particulates than rotary dryers. Flue-gas dryers can have more emission problems due to VOCs

Feed And Discharge Systems

Superheated steam dryers have more problems with leakage from the feeding and discharge systems compared to flue-gas dryers. This results in superheated steam dyers having lower availability; that is, more down time for maintenance.. Plug-screw feeders have worked better than other types of feeders but need to be replaced frequently due to wearing.

Fire Hazard

Superheated steam dryers have no fire hazard. In other types of dryers, fire hazard is lower in dryers that operate at lower temperatures, such as conveyor dryers. Fires result from ignition of dust or combustible gases, either inside the dryer or after the dryer. To reduce the potential for fire with hog fuel, the drying medium should not have an oxygen concentration greater than 10%.