Traveling Grate Kiln

The fluidized bed reactor is a vertical steel vessel to which TDF is fed through a side port. A fluidized bed of TDF is maintained with hot air. The abrasive action of the fluidized particles erode the char from the TDF, reducing the tire material to small pieces. As the TDF decomposes, ash and char are swept out of the reactor with the fluidizing air. The biggest disadvantages of a fluidized bed system are the need to remove entrained solids from the vapors, and the need to maintain the hot, fluidizing gas. 

The two main advantages are the good solids mixing and uniform solids temperature profile in the fluidized bed. These two advantages produce the finest grade char of any of the pyrolysis processes. 

---

Fig. 4. Multiphase fluid and fluid—solids reactors (a) bubble column, (b) spray column, (c) slurry reactor and auxiUaries, (d) fluidization unit, (e) gas—bquid—sobd fluidized reactor, (f) rotary kiln, and (g) traveling grate or belt drier.

The roasting process mostly applied to sulfidic sources is carried out in appliances of different types with different design features. Without describing their features and constructional details, it may simply be mentioned here that some of the widely acclaimed roasting units are traveling grate furnaces, multiple hearth furnace, rotary kilns, and fluid-ized-bed roasters. 

Dry process cement production facilities often have several other types of manufacturing equipment designed to increase fuel efficiency. First, many dry process kilns add a preheater to the feed end of the kiln to begin heating of the feed prior to its entrance to the kiln. Two main types of preheaters exist, the suspension preheater and the traveling grate preheater both use hot, exiting kiln air to facilitate a more efficient heat transfer to the feed than could occur in the feed end of the kiln itself.1 This... 

Pelletizing (cf. tumbling agglomeration ) Green balls or pellets of ore or minerals are hardened by heat treatment with attendant loss of moisture and volatile matter. Pellet induration, pellet firing Travelling grate, rotary kiln, vertical shaft furnace... 

Heat hardening of green iron-ore pellets is accomplished in a vertical shaft furnace, a traveling-grate machine, or a grate-plus-kiln combination (see Ball et al., op. cit.). 

Fig. 9.29 Schematic representation of the three most common heat induration (sintering) furnaces for iron ore pellets and sketches depicting the corresponding plants, (a) Shaft furnace, (b) straight (travelling) grate, (c) Grate-Kiln [B.42],...

Fig. 6.7-38 Traveling grate for the drying and partial calcination of pellets (agglomerates, nodules) prior to entry into the rotary kiln [B.69]...

Fig. 6.8-11 Diagrams of the three major furnace types used for the hardening of iron ore pellets a) shaft, b) traveling grate, c) grate-kiln D, Drying F, firing (sintering) C, cooling...

Fig. 6.8-17 I sometric drawings of the three major iron ore pelletizing processes [B.48, B.97], a) Balling drum circuits with shaft furnaces, b) Balling drum circuits with straight travelling grate machine, c) Balling drum circuit(s) or balling pan(s) with grate-kiln hardening system...

Various designs of lime cooler are used, and include planetary units mounted around the kiln shell, travelling grates and various types using louvres to contain the lime, while permitting the passage of air. 

ACL Kiln or Lepol Kiln. ACL is a trademark of the Allis Chalmers Mfg Co., USA Lepol is a trade-mark of Polysius Co., Germany. Both terms refer to a travelling-grate preheater for portland cement batch prior to its being fed to a... 

Large capacity, mixed feed, center burners Noncontact externally heated small capacity kilns used for niche applications Rotary hearth with traveling grate or calcimatic kilns... 

The main problems associated with the travelling grate cooler are those of achieving uniform distribution of the clinker across the width of the grate immediately after its discharge from the kiln. 

---