Rotary Kilns

Multiple Options – Flexible Service

At IBU-tec, 16 different rotary kilns are available for your projects, trials and production needs, giving you a full range of size and configuration options. This diverse spectrum of equipment is designed to be as versatile and adaptable as possible – as such, IBU-tec can offer clients almost any degree of thermal treatment necessary for project completion.

How Rotary Kilns Work

Rotary kilns (sometimes called calciners or rotary furnaces) are used for thermal treatment processes such as calcination, sintering, pyrolysis and firing, as well as for oxidation and reduction. These treatments can be applied to powders, granulates, suspensions and green bodies. A rotary kiln consists of a cylindrical, rotating body mounted between stationary material feed and outlet housings. The constant turning of the kiln body mixes the material, ensuring that it is processed homogeneously. Rotary kilns are heated either directly (inside the kiln chamber) or indirectly (from outside), depending upon the requirements of the application.

Direct Fired Rotary Kiln

In a direct-fired rotary kiln, the burner is situated inside the kiln body, that is, inside the reaction chamber. The material is heated directly by the burner flame and the stream of hot gas produced by the burner. These kilns are usually lined with refractory (heat-resistant) material so that they can be operated at higher temperatures than kilns with plain metal tubes. Directly fired kilns are highly robust and easily scalable and can be used to achieve high throughput rates with relatively low production costs.

Facts & Data

  • 4 direct heated rotary kilns
  • Temperature range: 100 – 1550°C
  • Residence time: 15 – 180 minutes
  • Reaction modes: continuous, batch, co-current, counter-current
  • Typical Processes: calcination , sintering , reduction , oxidation and drying
  • Rotary Kiln
  • Characteristics & Capacities

    Kiln
    name

    Heated
    kiln
    length
    [m]

    Inner diameter
    [m]

    Heating
    type

    Temperature
    range
    [°C]/[°F]

    Raw material
    throughput
    [kg/h]

    Mode of operation

    Special features

    GDO

    12

    1

    natural gas

    up to 1,500 / 2,732

    150 – 1,500

    counter-current (co-current)

    raw material silo, 10 m rotary cooler, cyclone preheater

    MDO

    4

    0.6

    natural gas

    up to 1,400 / 2,552

    50 – 500

    counter-current

    rotary cooler, cyclone preheater

    KDO

    7

    0.3

    natural gas

    up to 1,550 / 2,822

    10 – 100

    counter-current or co-current

    vibration cooler, rotary cooler, reducing gas atmosphere possible, afterburner

    BDO

    0.6

    0.35

    natural gas

    up to 1,400 / 2,552

    15 l per batch

    batch operation only

    batch kiln for small quantities

  • Downloads
    • IBU-tec Fact Sheet Directly Fired Rotary Kilns

      pdf, 1 MB

      Download

Indirect Fired Rotary Kilns

In contrast to directly fired kilns, indirect fired rotary kilns (also called rotary calciners) are equipped with natural gas burners or electric heating elements located outside the reaction chamber, so that the heat is transferred to the interior through the kiln shell. This arrangement makes it easy to operate the kiln with a controlled gas atmosphere in the reaction chamber (e.g. inert or reducing). Because combustion gases are kept out of the reaction chamber, the gas volume flow in an indirectly fired kiln is generally lower than in directly fired kilns. This means the indirect rotary kilns are excellent for treatment of very fine powders. They are also easier to clean, so that cross-contamination of materials can be more effectively prevented.

Facts & Data

  • Rotary Kiln
  • Characteristics & Capacities

    Kiln
    name

    Heated
    kiln
    length
    [m]

    Inner diameter
    [m]

    Heating
    type

    Temperature
    range
    [°C]

    Raw material
    throughput
    [kg/h]

    Mode of operation

    Special features

    IDO 10

    7

    1

    natural gas

    300 - 1,150

    100 - 1,000

    counter-current

    5 heating zones

    IDO 9

    7

    1

    natural
    gas

    300 - 1,100

    100 - 1,000

    counter-current

    defined gas atmposphere,
    5 heating zones, thermal oxidizer

    IDO 11*4.70.6electrical100 – 1,15040 – 400counter-current

    Inert and reducing, hydrogen-atmosphere,
    thermal oxidizer

    IDO 3

    4

    0.5

    natural
    gas

    300 - 1,150

    25 - 250

    counter-current or
    co-current, batch operation possible

    defined gas atmosphere,
    6 heating zones, thermal oxidizer

    IDO 6*3.750.45electrical100 – 90015 – 150counter-current

    3 heating zones,
    thermal oxidizer, DeNOx

    IDO 5

    3.5

    0.4

    natural gas

    300 - 1,100

    10 - 100

    counter-current or
    co-current

    defined gas atmosphere,
    3 heating zones, thermal oxidizer

    IDO 1

    3

    0.4

    electrical

    50 - 1,150

    10 - 100

    counter-current or
    co-current, batch operation possible

    defined gas atmosphere,
    3 heating zones, thermal oxidizer

    IDO 2

    2.5

    0.35

    electrical

    50 - 1,200

    10 - 75

    counter-current or
    co-current, batch operation possible

    4 heating zones

    IDO 7*2.30.254electrical100 – 9003 – 30counter-current

    Inert and reducing,
    thermal oxidizer

    IDO 4

    1

    0.1

    electrical

    50 - 1,100

    0.1 - 2

    counter-current or
    co-current, batch operation possible

    defined gas atmosphere, thermal oxidizer

    IDO 8

    1

    0.1

    electrical

    100 - 1,400

    0.1 - 2

    counter-current or
    co-current, batch operation possible

    ceramic & metal tube, defined gas atmosphere, thermal oxidizer

    IDO 120.90.4electrical50 - 1,100ca. 30 l / batchbatch operation only 

    *in construction

  • Downloads
    • IBU-tec Fact Sheet Indirectly Heated Rotary Kilns

      pdf, 1 MB

      Download

Your Benefits:

  • Unparalleled rotary kiln portfolio that is diverse and adaptable to all types of applications
  • Modular kiln design enables quick and easy adaptation to the specific challenges of your project
  • Ability to execute even the most challenging process conditions your project may demand
  • Decades of experience with rotary kilns for material development and production
  • Monitoring of the project and continuous quality control in our laboratories