Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
136 words
In apparatus for the heat treatment of fine-grained material having a multistage preheater communicating with a kiln via an upwardly extending exhaust gas duct forming a precalcination zone into which fuel is introduced between said kiln and said preheater, and a cooler into which heat treated material is delivered from said kiln, the improvement comprising a pair of cooling air ducts extending between said cooler and said exhaust gas duct and communicating with the latter at vertically spaced zones; means for introducing said fuel into each of said ducts to form a mixture of fuel and air for delivery into said exhaust gas duct adjacent each of said zones; and material duct means communicating between said preheater and the lower one of said cooling air ducts for delivering preheated material to the latter from said preheater.
Claim 2
Dependent Claim
136 words
In apparatus for the heat treatment of fine-grained material having a multistage preheater communicating with a kiln via an upwardly extending exhaust gas duct forming a precalcination zone into which fuel is introduced between said kiln and said preheater, and a cooler into which heat treated material is delivered from said kiln, the improvement comprising a pair of cooling air ducts extending between said cooler and said exhaust gas duct and communicating with the latter at vertically spaced zones; means for introducing said fuel into each of said ducts to form a mixture of fuel and air for delivery into said exhaust gas duct adjacent each of said zones; and material duct means communicating between said preheater and the lower one of said cooling air ducts for delivering preheated material to the latter from said preheater.
Claim 3
Dependent Claim
36 words
Apparatus according to claim 1 wherein one of said air ducts communicates with said exhaust gas duct substantially diametrally thereof and the other of said air ducts communicates with said exhaust gas duct substantially tangentially thereof.
Claim 4
Dependent Claim
22 words
Apparatus according to claim 1 wherein each of said air ducts communicates with said exhaust gas duct along a downwardly inclined path.
Claim 5
Dependent Claim
22 words
Apparatus according to claim 1 wherein the air duct at the higher zone communicates with said exhaust gas duct substantially tangentially thereof.
Claim 6
Dependent Claim
24 words
Apparatus according to claim 1 wherein the air duct at the lower of said zones communicates with said exhaust gas duct substantially diametrally thereof.
Claim 7
Dependent Claim
42 words
Apparatus according to claim 1 wherein the distance between said zones comprises a first precalcination section and the distance between the higher of said zones and said preheater comprises a second precalcination section, said first and second sections being of different lengths.
Claim 8
Dependent Claim
19 words
Apparatus according to claim 6 wherein said first precalcination section is shorter in length than said second precalcination section.
Claim 9
Dependent Claim
20 words
Apparatus according to claim 6 wherein said first precalcination section has a length of between about 4 and 8 m.
Claim 10
Dependent Claim
20 words
Apparatus according to claim 6 wherein said first precalcination section has a length of between about 5 and 6 m.
Claim 11
Dependent Claim
20 words
Apparatus according to claim 6 wherein said second precalcination section has a length of between about 7 and 15 m.
Claim 12
Dependent Claim
20 words
Apparatus according to claim 6 wherein said second precalcination section has a length of between about 9 and 12 m.