Abstract

The present invention refers to a manufacturing process of artificial pozzolan which has the final color gray. In order to perform the processes in the desired way, the kiln atmosphere shall contain low oxygen concentration and the presence of reducing agents. However the presence of carbon monoxide at the kiln outlet is not desirable, due to environmental impacts and the increase in specific heat consumption of the kiln. So the process described in this invention comprises the following steps: heating (1), which consists of heating the raw materials to a temperature between 100-350° C. until drying of the material to a moisture mass fraction of 0-5% (wet basis); mixing (2), which consists of mixing the dry raw materials from the heating process with the right proportion of fuel, in from 1% to 5% in mass fraction, according to the concentration of hematite present in the raw material; calcining (3), which consists of heating the fuel and raw materials blend to a temperature between 700-900° C., with oxygen concentration between 1-5% and, finally, cooling (4), which consists of an initial step of rapid decrease in pozzolan temperature until 600° C. and a final step of slow decrease in pozzolan temperature until 120° C.

IPC Classes  ?

• C04B 7/13 - Mixtures thereof with inorganic cementitious materials, e.g. Portland cements
• C04B 7/44 - BurningMelting
• C04B 7/47 - Cooling

Abstract

The present invention refers to a manufacturing process of artificial pozzolan which has the final color gray. In order to perform the processes in the desired way, the kiln atmosphere shall contain low oxygen concentration and the presence of reducing agents. However the presence of carbon monoxide at the kiln outlet is not desirable, due to environmental impacts and the increase in specific heat consumption of the kiln. So the process described in this invention comprises the following steps: heating (1), which consists of heating the raw materials to a temperature between 100-350°C until drying of the material to a moisture mass fraction of 0-5% (wet basis); mixing (2), which consists of mixing the dry raw materials from the heating process with the right proportion of fuel, from 1% to 5% in mass fraction, according to the concentration of hematite present in the raw material; calcining (3), which consists of heating the fuel and raw materials blend to a temperature between 700-900°C, with oxygen concentration between 1-5% and, finally, cooling (4), which consists of an initial step of rapid decrease in pozzolan temperature until 600°C and a final step of slow decrease in pozzolan temperature until 120°C.

IPC Classes  ?

• C04B 7/47 - Cooling
• C04B 14/16 - Minerals of vulcanic origin porous, e.g. pumice
• C10L 5/02 - Briquettes consisting mainly of carbonaceous materials of mineral origin

Abstract

There is described a burner barrel (102) comprising a concentric multi-tubular structure, formed by pipes (111-115) and wherein at the end downstream the said burner barrel (102) is provided a burner tip (120) in which various nozzles to inject fuel and primary air (Ap) are perforated. Said burner tip (120) comprises at least one series of nozzles (121) intended to inject an external air flow; a second series of nozzles (122) intended to inject tangential air flow; a third series of apertures (123) intended to inject the fuel and transport air. The ends downstream the first (111) and second (112) burner pipes are joined and define a continuous external annular surface (131) of the burner tip (120), and wherein said nozzles (121) arranged within an inscribed area (141), being the dimension of the nozzles (121) limited by a rate between the open area A of the nozzles (121) and the complementary closed area A.

IPC Classes  ?

• F23D 1/00 - Burners for combustion of pulverulent fuel
• F23D 11/40 - Mixing tubesBurner heads
• F23D 1/04 - Burners producing cylindrical flames without centrifugal action

Abstract

The present invention relates to a system for gasifying solid and liquid fuels in a compact chamber. Metal reduction and ore calcination processes can be specifically mentioned among such processes. The system for gasifying solid fuels in a compact chamber comprises: (a) a combustion chamber (1) consisting of an internal shell (4) lined with a refractory material (19) and having various primary air injection apertures (21), one or more tangential water injection lances (11), one or more tangential solid fuel injection lances (22) next to the wall of the antechamber of the external shell (5), an auxilliary burner nozzle (25) and a pilot connection point (24); (b) a support and transport carriage (2); (c) an air supply system (3); (d) a solid fuel conveying air blower (13); (e) a solid metering system (12); (f) conveying air and primary air pipes (7); (g) a measurement and control panel (18) for auxiliary fuel (oil and natural gas).

IPC Classes  ?

• F23C 1/00 - Combustion apparatus specially adapted for combustion of two or more kinds of fuel simultaneously or alternately, at least one kind of fuel being either a fluid fuel or a solid fuel suspended in air
• F23C 1/06 - Combustion apparatus specially adapted for combustion of two or more kinds of fuel simultaneously or alternately, at least one kind of fuel being either a fluid fuel or a solid fuel suspended in air lump and pulverulent fuel