The present invention discloses a cooler for cooling particulate material which has been subjected to heat treatment in an industrial kiln, such as a rotary kiln for manufacturing cement clinker. This cooler comprises an inlet, an outlet, end wall, side walls, a bottom and a ceiling, at least three reciprocating supporting lanes for receiving, supporting and transporting the material to be cooled, the lanes are moving following the walking floor principles as well as means for injecting cooling gas into the material through grate plates in the lanes. With the present invention it is an aim to have an increase in the vertical shearing height, and still having stationary clinker on top of the grate plates.

High temperature furnaces, calcining, pyrolysis and other high temperature manufacturing processes, composition rearrangements, and equipment. Systems, equipment and processes using oxyfuel combustion using gaseous fuels for cement manufacture. Reactor furnaces using oxyfuel containing natural gas and gravity feed to process pellets forming a pellet bed into cement.

High temperature furnaces, calcining, pyrolysis and other high temperature manufacturing processes, composition rearrangements, and equipment. Systems, equipment and processes using oxyfuel combustion using gaseous fuels for cement manufacture. Reactor furnaces using oxyfuel containing natural gas and gravity feed to process pellets forming a pellet bed into cement.

A method of carbonating cement powder and use thereof. An amount of water is supplied to an initial cementitious powder to create a moistened cementitious powder. Carbon dioxide is supplied to the moistened cementitious powder, while mechanically stirring the moistened cementitious powder, to cause a reaction of the carbon dioxide with the moistened cementitious powder to produce a carbonated cementitious material. The carbonated cementitious material is dried and ground to produce a carbonated cementitious powder. The carbonated cementitious powder may be combined with ordinary cement and various ingredients or additives, such as retarders, accelerators and extenders for use in well cementing applications. Methods for cementing casing, liners and remedial operations such as plugging back, and squeeze cementing are also provided. Methods for producing a low alkaline cement suitable for high CO.sub.2 gas wells are also provided. Methods to achieve a stable retarded cement used in higher temperatures are provided.

A method of carbonating cement powder and use thereof. An amount of water is supplied to an initial cementitious powder to create a moistened cementitious powder. Carbon dioxide is supplied to the moistened cementitious powder, while mechanically stirring the moistened cementitious powder, to cause a reaction of the carbon dioxide with the moistened cementitious powder to produce a carbonated cementitious material. The carbonated cementitious material is dried and ground to produce a carbonated cementitious powder. The carbonated cementitious powder may be combined with ordinary cement and various ingredients or additives, such as retarders, accelerators and extenders for use in well cementing applications. Methods for cementing casing, liners and remedial operations such as plugging back, and squeeze cementing are also provided. Methods for producing a low alkaline cement suitable for high CO.sub.2 gas wells are also provided. Methods to achieve a stable retarded cement used in higher temperatures are provided.

A process for producing cement clinker may involve preheating raw meal in a preheater, calcining the preheated raw meal in a calciner, burning the preheated and calcined raw meal in a furnace to give cement clinker, cooling the cement clinker in a cooler, branching off a portion of the furnace offgases flowing out of the furnace as bypass gas, cooling the bypass gas in a mixing chamber with a cooling gas, and separating out dust present in the bypass gas. The cooling gas is formed at least partly or completely from the bypass gas and/or the calciner offgas and/or the preheater offgas. The cooling gas is introduced into the mixing chamber in a ratio of 2-10:1 relative to the bypass gas.

A process for producing cement clinker may involve preheating raw meal in a preheater, calcining the preheated raw meal in a calciner, burning the preheated and calcined raw meal in a furnace to give cement clinker, cooling the cement clinker in a cooler, branching off a portion of the furnace offgases flowing out of the furnace as bypass gas, cooling the bypass gas in a mixing chamber with a cooling gas, and separating out dust present in the bypass gas. The cooling gas is formed at least partly or completely from the bypass gas and/or the calciner offgas and/or the preheater offgas. The cooling gas is introduced into the mixing chamber in a ratio of 2-10:1 relative to the bypass gas.

A cement production plant may include a preheater for preheating raw meal, a calciner for calcining the preheated raw meal, and a furnace with a furnace burner for firing the raw meal to form cement clinker. The furnace has a combustion gas inlet for admitting a combustion gas with an oxygen content of 30% to 75% into the furnace. The cement production plant may also include a cooler for cooling the cement clinker. The calciner and the furnace each have at least one respective fuel inlet for admitting at least one fuel into the calciner and the furnace. The calciner and the furnace each have at least one respective inert gas inlet for respectively admitting inert gas into the calciner and the furnace.

A cement production plant may include a preheater for preheating raw meal, a calciner for calcining the preheated raw meal, and a furnace with a furnace burner for firing the raw meal to form cement clinker. The furnace has a combustion gas inlet for admitting a combustion gas with an oxygen content of 30% to 75% into the furnace. The cement production plant may also include a cooler for cooling the cement clinker. The calciner and the furnace each have at least one respective fuel inlet for admitting at least one fuel into the calciner and the furnace. The calciner and the furnace each have at least one respective inert gas inlet for respectively admitting inert gas into the calciner and the furnace.

A cement clinker producing system, capable of providing a gas containing a carbon dioxide gas at a high concentration by increasing a carbon dioxide gas concentration for a part of an exhaust gas, includes a cyclone preheater to preheat a cement clinker raw material, a rotary kiln to burn the preheated cement clinker raw material so as to provide cement clinker, a calcination furnace to promote decarbonation of the cement clinker raw material, a clinker cooler to cool the cement clinker, a kiln exhaust-gas discharge passages to discharge an exhaust gas generated in the rotary kiln, a combustion-supporting gas supply device to supply a combustion-supporting gas having a higher oxygen concentration than air, a combustion-supporting gas supply passage to guide the combustion-supporting gas to the calcination furnace, and a calcination furnace exhaust-gas discharge passage to discharge a carbon dioxide gas-containing exhaust gas generated in the calcination furnace.