Single tube dryers are commonly used in the quartz sand drying process, but
many customers have reported that the drying speed slows down after running the
equipment for a period of time, and the moisture content of the discharged
material cannot be reduced. The problem usually lies in three aspects: heat
source, plate reading, and speed.
Insufficient heat source temperature or heat loss is the primary reason for
slow drying. When the carbon deposition on the nozzle of a gas burner exceeds
2mm, the heat output can decrease by more than 30%. When inspecting, first check
the color of the burner flame. If it turns yellow or red, it indicates
insufficient combustion. Clean the nozzle and adjust the air door opening to 30%
-40%. At the same time, check whether the insulation layer of the cylinder is
intact. If the insulation layer is damaged or missing, a large amount of heat
will be lost. If the surface temperature of the cylinder exceeds 60 ℃, it
indicates that the insulation effect is not up to standard and rock wool
insulation layer should be installed or replaced.
The copied board is worn or detached, and the material cannot be lifted. When
the wear of the lifting plate (copying plate) exceeds one-third of the original
height, the quartz sand cannot be fully lifted and scattered, and a large amount
of wet sand accumulates at the bottom of the cylinder to form a "dead material
zone", greatly reducing the heating area. It is recommended to check the wear of
the copied board once a month, and replace the same specification parts directly
if the wear becomes thinner or breaks. During installation, the bolts must be
tightened to prevent them from falling off again due to vibration during
operation.
The rotational speed of the cylinder is not suitable and the residence time
is not enough. When the rotational speed exceeds 4 r/min, the material residence
time is less than 15 minutes, and the water cannot evaporate in time; When the
speed is below 2r/min, the material accumulates too thick and the hot air flow
cannot penetrate. Suggest adjusting the speed to 2.5-3 r/min, and reducing the
speed appropriately to extend the drying time when the moisture content is too
high.
If the dryer is drying slowly, don't rush to change the equipment. First
check if the heat source temperature is sufficient, if the board is not ground,
and if the speed is appropriate. For equipment operation related issues, please
feel free to contact the technical team of Shandong Heavy Industry: Manager
Zhang at 13583776655 (same as WeChat).