5-20rpm Rotating Speed KJG-5 Blade Paddle Vacuum Drying Machine

The continuous horizontal paddle dryer consists of a jacketed trough and two hollow shafts with hollow paddles. On the trough is a cover with the inlet for the material to be dried. The material is dried by heat transfer with the heating medium like steam, thermal oil or hot water which is flowing through the hollow shafts, hollow paddles and dimple jacket or half pipe jacket. The dried product is removed from the discharge chute via a shaftless screw conveyor. The exhaust vapors leave the dryer through an exhaust outlet on the cover. The absence of air during the drying process results in a very safe operation due to lowest oxygen content, a small and compact odour treatment and it offers the possibility of a heat recovery system in the vapour condensing unit due to the high dew point of the off-gas.

The trough is omega shaped with a jacket. The material is fed at one end of the machine and will be transported by gravity, under a slight angle of the trough or by asymmetric paddles, to the outlet of the machine at the other end. During the residence time of the material in the machine, a perfect plug flow is maintained, guaranteeing perfect uniform product quality. The product level inside the machine is secured by an adjustable overflow weir. Overflow weir at the product outlet side has manually operated emptying valves at the bottom of the product removal before a production stop. Product outlet chute at the bottom of the trough has a rectangular flange to connect to the downstream equipment.

A horizontal spiral screw conveyor is mounted underneath the rectangular outlet flange of the discharge chute, to remove the product from the trough. The spiral screw conveyor has two bottom outlets, one on each end of the conveyor. In combination with the bi-directional rotation of the screw conveyor, the product can be transported to either one of these product outlets.

The dryer has two hollow shafts with hollow wedge-shaped or cuneiform shaped paddles arranged in staggered position. Heating medium is introduced at one side of the shafts and flows in parallel through the paddles. The paddles are wedge shaped for optimal contact with the product and consequently good heat transfer at the product side as well. The heating medium leaves the shafts at the same side as it comes in. To protect against abrasion, the paddles will be coated with tungsten carbide abrasion-resistant coating. The hollow design of the paddle shafts means that the entire interior surface acts as one large heat exchanger. Controlled agitation by the rotating shafts with paddles deliver superb product-to-surface interaction, for an optimal heat transfer rate. Energy requirements are modest, especially if compared to direct drying with its associated large hot air flows. The heat transfer in the paddle dryer is very high. The two rotating paddle shafts in the trough ensure optimal heat transfer and mixing.

On the dust tight cover are the product inlet, the vapour outlet, two inspection ports and a man hole. Together with the upper part of the trough a gas/vapour dome is created. The cover can be optionally heat traced to prevent any risk of condensation. Sweep gas can be introduced through nozzles at the product inlet- and outlet side.

The main shaft seals are effected with stuffing boxes. The stuffing boxes are flexibly connected with the trough end plates, such that they can follow small movements of the shafts and still maintain tightness. On the shafts wear sleeves at the sealing area prevent shaft damage by abrasion. The stuffing boxes have a lantern ring for a gas purge. The bearings are roller bearings with oil lubrication. The heat transfer medium is introduced into and removed from via the same rotary joints on one side of the shaft. The shaft is drive by a motor with hard faced gearbox. Between the shafts are two meshing spur gears which can ensure identical rotational speed. Speed is fixed and doesn’t require variation. The rotational speed can only be regulated by VFD.

KJG-5 Horizontal Hollow Paddle Dryer Main Feature

The main structure is a W-shaped shell with a jacket, which is equipped with a pair of hollow low-speed rotating hollow shafts. A number of mixing blades are welded on the shaft. The jacket and the hollow mixing blades are all equipped with heat carriers, and the two heating surfaces heat the materials at the same time. The heat carrier is usually fed from the middle of the dryer and discharged from the other side through the surface of the material layer in the agitated state.

Wedge-shaped hollow blades are densely arranged on the hollow shaft, and the thermal medium flows through the blades through the hollow shaft. The unit effective volume has a large heat transfer area. The temperature of the thermal medium ranges from - 40 ° C to 320 ° C, which can be water vapor or liquid type: such as hot water, heat transfer oil, etc. Indirect conduction heating does not carry air to take away heat. Heat is used to heat materials. The heat loss is only the heat dissipation to the environment through the insulation layer of the reactor body. The heat transfer surface of the wedge-shaped blade has the function of self-cleaning. The relative movement of the material particles and the wedge-shaped surface can wash off the attached materials on the wedge-shaped surface, so that the clean heat transfer surface is kept in motion all the time.

KJG-5 Horizontal Hollow Paddle Dryer Working Principle

Hollow shaft dense arrangement with the wedge-shaped hollow blade, the heat medium through the hollow shaft flow through the blade. The effective volume of heat transfer area is very large, the heat medium can be water vapor, can also be hot water or heat conducting oil. The heat transfer medium flows through the shell jacket and the hollow stirring shaft through the rotating joint, and the hollow stirring shaft has a different internal structure according to the type of the heat medium to ensure the best heat transfer effect.

In the pulp and jacket access to hot oil, heating at the same time, the upper part of the discharge port at the same time through the heated dry air after further drying, thus greatly increasing the drying strength of the device. Evaporated moisture from the tail gas out of the dryer, wet air discharged by the induced draft fan outdoors.

KJG-5 Horizontal Hollow Paddle Dryer Technical Parameters

No.	Item	Parameters	Note
1,	Model	KJG-5
2,	Paddle heat transfer area [m2]	3.5	Including shaft surface area
3,	Jacket heat transfer area [m2]	1.5
4,	Total heat transfer area [m2]	5
5,	Water evaporation [kg/h]	50
6,	Output capacity [kg/h]	15-20
7,	Diameter of paddle [mm]	260
8,	Effective volume [m3]	1
9,	Speed of rotation [rpm]	1-15
10,	Standard motor rating [kW]	3
11,	Carrier gas flow [m3/h]	300-500
12,	Carrier gas exhaust fan motor rating [kW]	0.75
13,	Machine floor space [L×W×H]	2816X760X1370
14,	Standard lifting weight [kg]	1500

KJG-5 Horizontal Hollow Paddle Dryer Show

Contact us