Providing a cement production apparatus in which raw material is supplied into a duct with being dispersed uniformly so that heat-exchanging efficiency is improved by even preheating and clogging and the like are prevented, so that stable operation can be carried out. Between cyclones at an upper stage and a cyclone at a lower stage disposed below cyclones at an upper stage, a duct 21 is provided to introduce exhaust gas to the cyclones at the upper stage with distributing after flowing upward from the cyclone at the lower stage; at a lower position than a distribution part 23 of the duct 21, a material-supplying pipe 22 is connected for supplying cement raw material; at a connected part of the material-supplying pipe 22 to the duct 21, a material-guiding chute 24 on which the cement raw material is supplied from the material-supplying pipe 22 and which drops it into the duct 21 is provided with protruding into the duct 21; and the material-guiding chute 24 is formed to have a flat upper surface and to be expandable by sliding so that insertion depth of a tip end 24a from an inner-wall surface 21b of the duct 21 is 0.15 to 0.5 times of an inner diameter of the duct 21.

Providing a cement production apparatus in which raw material is supplied into a duct with being dispersed uniformly so that heat-exchanging efficiency is improved by even preheating and clogging and the like are prevented, so that stable operation can be carried out. Between cyclones at an upper stage and a cyclone at a lower stage disposed below cyclones at an upper stage, a duct 21 is provided to introduce exhaust gas to the cyclones at the upper stage with distributing after flowing upward from the cyclone at the lower stage; at a lower position than a distribution part 23 of the duct 21, a material-supplying pipe 22 is connected for supplying cement raw material; at a connected part of the material-supplying pipe 22 to the duct 21, a material-guiding chute 24 on which the cement raw material is supplied from the material-supplying pipe 22 and which drops it into the duct 21 is provided with protruding into the duct 21; and the material-guiding chute 24 is formed to have a flat upper surface and to be expandable by sliding so that insertion depth of a tip end 24a from an inner-wall surface 21b of the duct 21 is 0.15 to 0.5 times of an inner diameter of the duct 21.

A process for heating a metal feedstock (31) fed in continuous to a smelting furnace (30) through a second horizontal heating section (34) through which hot discharge fumes collected from said furnace (30) pass, said fumes exerting a heating phase of said feedstock (31), characterized in that, immediately before entering said second heating section (34), the feedstock (31) is subjected to a preheating phase by heating means other than the discharge fumes collected from the smelting furnace (30). In a plant for the embodiment of said process, said different heating means are envisaged inside a first preheating section (33), which is operatively connected with said second heating section (34) by means of an intermediate fume evacuation section (35), the fumes coming from said sections (33) and (34) being conveyed to said section. Said sections (33, 34) preferably have a tunnel configuration.

An apparatus to move and preheat metal material (M) to be fed to a container comprises a containing structure, having an internal compartment and provided with a support wall, a conveyor for the material (M), a fume transit section whose volume reduces as it is distanced from said container along the longitudinal development of said containing structure, and a collector for hot fumes (F) whose volume increases in a manner correlated to said reduction in the fume transit section. The collector is located below said conveyor inside the internal compartment essentially along the entire longitudinal development of said containing structure. Moreover, one or more through apertures are made in said support wall to put the conveyor and the collector into fluidic connection.

Apparatus for continuously conveying and pre-heating a metal charge inside a container of a melting plant, includes at least a channel for conveying the metal charge, at least a hood disposed above the conveyor channel defining a tunnel and/or an expansion chamber, inside which at least part of the fumes exiting from the container advance, and apertures made in cooperation with lateral walls of the conveyor channel to discharge the fumes. The conveyor channel includes an activator that divert the fumes and/or delimit the zone occupied by the metal charge of the conveyor channel, and that cooperate longitudinally with at least part of the conveyor channel.

Apparatus for continuously conveying and pre-heating a metal charge inside a container of a melting plant, includes at least a channel for conveying the metal charge, at least a hood disposed above the conveyor channel defining a tunnel and/or an expansion chamber, inside which at least part of the fumes exiting from the container advance, and apertures made in cooperation with lateral walls of the conveyor channel to discharge the fumes. The conveyor channel includes an activator that divert the fumes and/or delimit the zone occupied by the metal charge of the conveyor channel, and that cooperate longitudinally with at least part of the conveyor channel.

The invention pertains to the heating of a metal strip, and relates to equipment for heating a metal strip that comprises a pre-heating housing provided with a device for projecting hot gases towards the strip, a heating housing with regenerative burners, a duct for discharging the gases from the heating housing, a three-way adjustable valve and an adjustment device including a sensor for detecting the setpoint temperature of the metal strip and a member for adjusting the three-way valve so that it can adjust the amount of hot gases fed to the projection device. The invention can be used in equipment for heating narrow strips before annealing the same.

The invention pertains to the heating of a metal strip, and relates to equipment for heating a metal strip that comprises a pre-heating housing provided with a device for projecting hot gases towards the strip, a heating housing with regenerative burners, a duct for discharging the gases from the heating housing, a three-way adjustable valve and an adjustment device including a sensor for detecting the setpoint temperature of the metal strip and a member for adjusting the three-way valve so that it can adjust the amount of hot gases fed to the projection device. The invention can be used in equipment for heating narrow strips before annealing the same.

An apparatus to feed and pre-heat a metal charge to a melting furnace of a steelworks comprises a feeding and pre-heating tower separate from the melting furnace provided with at least one compartment to temporarily contain said metal charge, transfer means to transfer said metal charge to said melting furnace and conveying means to convey the fumes exiting from the melting furnace to said compartment. The apparatus also comprises a post-combustion chamber, disposed adjacent to and below said compartment, and connected on one side to said compartment and on another side to said conveying means, the post-combustion chamber being configured to determine the expansion of the fumes introduced by the conveying means and to direct said expanded fumes toward said compartment along a path such as to determine a desired residence time of said fumes suitable to obtain at least the substantial complete combustion of the unburned gases present in said fumes.

An apparatus to feed and pre-heat a metal charge to a melting furnace of a steelworks comprises a feeding and pre-heating tower separate from the melting furnace provided with at least one compartment to temporarily contain said metal charge, transfer means to transfer said metal charge to said melting furnace and conveying means to convey the fumes exiting from the melting furnace to said compartment. The apparatus also comprises a post-combustion chamber, disposed adjacent to and below said compartment, and connected on one side to said compartment and on another side to said conveying means, the post-combustion chamber being configured to determine the expansion of the fumes introduced by the conveying means and to direct said expanded fumes toward said compartment along a path such as to determine a desired residence time of said fumes suitable to obtain at least the substantial complete combustion of the unburned gases present in said fumes.