Rotary Drum dryer

rotary drum dryer

What is a rotary dryer?

The rotary dryer also known as rotary drum dryer is a kind of industrial dryer that can dry high humidity moisture materials by direct or indirect heating, It is a tilted or horizontal and rotating cylinder,  Rotary drum dryer occupies a very important position in the chemical, agricultural, coal, building materials, and light industrial industries.

Advantages and Features-Rotary dryers manufacture

  • Rotary drum dryer by Qingdao Palet Machinery is specially designed for drying the sawdust, wood shavings, wood chips, woodblocks, rice hull, chicken manure, grass, bean dredges, cassava residue, cassava residue, sludge, etc.
  • The structure of the rotary dryer adopts the means of cylinder marginal transmission, flange connection, direct heat transfer.
  • Large capacity and fully automatic.
  • Low energy cost and low resistance.
  • suitable for a wild range of material sizes.
  • Stainable, low cost of operation, product the average humidity reduction is good.

Rotary dryer working principle

Rotary dryers specification and parameter

ModelSpecification (m)Capacity(T/h)Rotate speed(r/min)Power(kw)Install angle(°)weight(T)

Rotary dryer systems

rotary dryer system
1Materials7Feeding Cover13Pinion gear19Cyclone separator
2Feeding Conveyor8Roller Ring14Couplings20Pipe
3Fuel elevator9 Carrier Roller15Motor21Chimney
4Hot air furnace/Gas Stove10Rotary dryer16Retaining Wheel22Fan
5Hot air pipe11Gear Box17Sealing Ring23Discharging Conveyor
6Inlet12Large Gear18Outlet24Finished product

What is the principle of the rotary dryer?

Rotary dryers work by tumbling and drying material in a rotating drum. The Materials to be dried enter into the dry zone of special combination plates are thrown by the drying plate for vertical movement because of angle difference and rotational motion of the drying plate. After making heat exchange with the materials, the high-temperature furnace gas discharged into the cylinder evaporates water and drys the material, it can prevent the material from sticking on the inside of the cylinder. It is a part of the pellet mill plant.

Rotary drum dryer design(Rotary Dryer Calculations)

Qingdao PALET Machinery can design and manufacture the Rotary Dryer Machine, dryer equipment for the customers especially according to the information of material. This raw material is wood chips, sawdust, etc.

The information as follows:

the production is 2 ton per hour.

A:Drying intensity (38kg/m3h)

G1:Dry Material Production (2t/h)

V:Dry Space needed(m3)

W1:Initial Moisture Content(60%)

W2:Final Moisture Content(15%)

Material Calculation:

For every 1000kg wet material evaporation and moisture content:


For every 1000kg wet material quantity after evaporate:


To produce 1000kg of end product need to feed in:

G=1000/470.5×1000=2125.3kg(wet raw material)

Rotary Dryer Calculation:

Volume calculation:




Provided Rotary  Dryer dimension:φ2.0×20m

V=πr²L=3.14x(1)²x20=62.8>59.2m3(fulfill requirement)

Classification of rotary dryers

  1. Direct-heated rotary dryer. The parallel current type, counter-current type, and staggered flow type. Parallel flow type is the hot air and materials moving in the same direction, but Counter current type is the direction of hot air flow is opposite to the direction of material movement.
  2. Indirect-heated rotary dryer. The built-in heating tube type and cylinder wall heating type.
  3. Special types, such as triple pass rotary drum dryer

Rotary drum dryer details show

inside structure

transmission systerm

rotary dryer transmission

small gear and big gear

small gear and big gear

rotary dryer riding wheel

riding wheels

Rotary dryers application

  1. Building materials industry: drying raw materials used in construction and engineering, mainly sand, river sand, yellow sand, cement, clay, grass charcoal soil, etc.
  2. Agriculture: drying wine lees, chicken manure, straw and sawdust, alfalfa, wood chips, wood shaving, etc.
  3. Industrial industry: drying industrial products or by-products, such as drying paper mill offcuts waste paper pulp, plastic waste, desulfurization gypsum, fly ash and industrial sludge, etc.
  4. Mineral processing industry: used in the process of processing various mineral products after mining, to play a role in bulk drying, can dry materials such as: coal processing industry coal sludge, lignite, cinder, flotation coal, etc.; smelting processing industry ore, mineral powder, slag, copper ore, laterite nickel powder, tailing slag, etc.; sand and gravel industry quartz sand, limestone, active lime, etc.

Advantages and disadvantages of rotary dryer

1.Rotary dryer has strong overload resistance, large processing capacity, low fuel consumption, and low drying cost;

2. Rotary Drum dryer can change the operating parameters according to different material properties so that the material can form a stable full break fabric screen in the dryer cylinder, and the quality heat exchange is more adequate;

3. Rotary Drum dryer adopts new feeding and discharging device, which eliminates the phenomenon of vertical dryer feeding blockage, discontinuity, unevenness, and material return, and reduces the load of dust removal system;

4. If the dryer is larger and the airflow speed is faster, there will be dust entrainment, so dust removal equipment and dust recovery equipment are needed.

What are the Rotary dryer parts?

The  Dryer riding wheel、Gear Box、pinion gear、large gear、rolling ring.  Qingdao PALET produces a wide range of rotary dryer parts. Qingdao palet machinery is one of the biggest rotary dryer manufature in china.

Rotary dryer riding wheel

rotary dryer gear box

Transmission-Gear box

Rotary dryer large gear

How to Correctly Operate Rotary Drum Dryer ?

we prepare the teaching videos in terms of installation, operation, parts replacements, repair and maintenance parts. And 7/24 email and phone call service is available.

The videos of rotary drum dryer

For detail and price of rotary dryer , please refer to:


Mobile: +86-13406817961

Note: Please feel free to give your inquiry in the form below. We will reply to you with details within 24 hours!