Abstract

Cement clinkers are produced by the dry method using a rotary kiln, wherein a portion of the gas emitted by the kiln is aspirated as bypass gas in the region between the rotary kiln (40) and the calcinator (20). The bypass gas is cooled by being mixed with a cooling medium which is heated by the mixing process and separated from the mixture, and the separated cooling medium is returned to the burning process, as a result of which the heat, which was taken over by the cooling medium from the bypass gas, is returned once again to the burning process. The preheater (10) for the raw meal can have multiple cyclone steps (11 to 15). Cooling meal is the cooling medium and is heated, and the bypass gas is cooled to a temperature which corresponds to the meal temperature of the second lowest cyclone step (14) of the preheater (10) for the raw meal. The cooling meal can be charging meal for the preheater or meal from one of the upper cyclone steps (11).

IPC Classes  ?

• F27B 7/20 - Details, accessories or equipment specially adapted for rotary-drum furnaces
• C04B 7/60 - Methods for eliminating alkali metals or compounds thereof

Abstract

The system for producing cement clinkers from raw meal comprises a reactor (20) for gasifying or carbonizing solid fuels, substitute fuels and/or secondary fuels for use of the fuel energy thereof for raw meal decarbonization in a calciner (12) and partially already in the reactor (20), wherein the reactor (20) is supplied with circulating hot air from the clinker cooler (16) via a tertiary air line (18). The reactor (20) overall has the outer shape of an oblique tube piece, cube or cuboid and is provided on the inside with a plurality of steps (22).

IPC Classes  ?

• F27B 7/20 - Details, accessories or equipment specially adapted for rotary-drum furnaces
• C04B 7/44 - BurningMelting

Abstract

According to the invention, raw meal is fed into the calciner (10) of an installation for producing cement clinker, the raw meal being delivered pneumatically to the calciner (10) by means of a gas stream. The gas stream is introduced into the calciner (10) in an essentially horizontal manner. The gas stream is conducted with the least possible flow resistance in the calciner (10). The gas stream that delivers the raw meal to the calciner (10) is the tertiary air stream (12). A tertiary air line or bifurcated tertiary air line (12) opens into the calciner and a raw meal feed line (15) opens into the tertiary air line (12) at a short distance upstream of the calciner or bifurcation.

IPC Classes  ?

• F27B 7/20 - Details, accessories or equipment specially adapted for rotary-drum furnaces
• C04B 7/43 - Heat treatment, e.g. precalcining, burning, meltingCooling

Abstract

According to the invention, raw meal is fed into the calciner (10) of an installation for producing cement clinker, the raw meal being delivered pneumatically to the calciner (10) by means of a gas stream. The gas stream is introduced into the calciner (10) in an essentially horizontal manner. The gas stream is conducted with the least possible flow resistance in the calciner (10). Solid fuel is delivered pneumatically to the calciner (10) by means of a delivery air stream (34) via a raw meal feeder skip (22). The gas stream that delivers the raw meal to the calciner (10) is the delivery air stream (34) for the fuel and said stream (34) is conducted parallel to the lateral walls (26) of the raw meal feeder skip (22). The device for this purpose has a meal feeder skip (22) comprising a meal chute (32) and the fuel delivery line (34) opens into the meal chute (32) from the rear in an essentially horizontal manner.

IPC Classes  ?

• F27D 3/00 - ChargingDischargingManipulation of charge
• C04B 7/43 - Heat treatment, e.g. precalcining, burning, meltingCooling

Abstract

The invention relates to the production of cement clinker in a dry process wherein the raw material is ground in a raw mill (20) to form cement raw meal, the raw meal is preheated in a raw meal preheater (16) and is precalcinated in a calcinator (14), the remainder of the hot meal is calcinated in a rotating kiln (12) and is burnt to form cement clinker. The cement clinker in cooled in a grate cooler (10), the waste gas of the rotating kiln (12) is guided to the calcinator (14) and the primary air is guided to the rotating kiln (12) by means of a primary air ventilator (36). Said system can be operated in a combined operation with raw meal grinding and in a direct operation without raw meal grinding. In the combined operation of the rotating kiln (12), the raw meal prewarmer (16) and the raw mill (20) work in a gas compound, in which the hot gas of the raw meal prewarmer (16) is guided to the raw mill (20) and is then released into the open as waste gas by a waste gas flue (30). In direct operation, the hot gas of the raw meal prewarmer (16) is directed past the raw mill (20) to the waste gas flue (30). In the combined operation, one part of the waste gas is guided to the rotating kiln (12) as primary air and in the direct operation, one part of the waste gas is guided together with the fresh air to the rotating kiln (12) as primary air.

IPC Classes  ?

• F27B 7/36 - Arrangements of air or gas supply devices
• C04B 7/44 - BurningMelting

Abstract

The container-calcinator (12) is used to precalcinate raw meal (31) in the production of cement clinkers. The calcinator (12) is a container in which it joins below the calcinator waste gas line of the rotating kiln (16) and leads away over the calcinator waste gas line. Devices for guiding the raw meal, fuel and tertiary air are provided. The combustion chamber of the calcinator (12) is sub-divided in the vertical direction into a lower reaction area (51), a central reaction area (52) and an upper reaction area (53). One first part of the fuel (42) and one first part of the raw meal (31) is evacuated at the end of the lower reaction area (51). One second part of the fuel (42) and one second part of the raw meal (31) is evacuated at the lower end of the central reaction area (52) and one first part of the tertiary air (44) is fed. One second part of the tertiary air is guided to the lower end of the upper reaction area (53). Each amount of tertiary air flows through two or more connection opening in the calcinator.

IPC Classes  ?

• F27B 7/20 - Details, accessories or equipment specially adapted for rotary-drum furnaces
• C04B 7/43 - Heat treatment, e.g. precalcining, burning, meltingCooling

Abstract

The mixing chamber (30) is arranged in a calcinating step (12) of a system for producing cement clinker. The calcinating step (12) comprises an ascending branch of a pipe conduit (24) and a descending branch of a pipe conduit (26), on which the upper end of the waste gas flow is deviated from the ascending branch of a pipe conduit (24) into the mixing chamber (30) in the descending branch of the pipe conduit (26). The mixing chamber (30) is formed such that the ascending branch of the pipe conduit (24) and the descending branch of the pipe conduit (26) meet each other in a pipeline fork (32) at an angle of 25 to 45° and a chamber (34) is arranged over the pipeline fork (32). The diameter and the height of the chamber (34) corresponds approximately to the diameter of the ascending branch of a pipe conduit (24) or to the descending branch of the pipe conduit (26). One of the two branches of the pipe conduit is usually oriented vertically.

IPC Classes  ?

• F27B 7/20 - Details, accessories or equipment specially adapted for rotary-drum furnaces
• C04B 7/43 - Heat treatment, e.g. precalcining, burning, meltingCooling