JPH033155B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fluidized sintering apparatus for powder raw materials such as cement and alumina.

In high-temperature firing of powder raw materials, it is effective to burn the fuel directly inside the fluidized bed, but in the case of large fluidized fluidized furnaces, the fuel is injected from burners arranged around the furnace, and the central high-speed wind It is difficult to mix the air from the tube and the air diffuser pipe in a short time and achieve complete combustion, and the movement of particles near the furnace wall is slow, resulting in local overheating that can cause raw material particles to burn or fuse. It is conceivable that this phenomenon may occur.

The present invention provides a fluidized fluidized firing device for powder raw materials that has no combustion delay even in a large fluidized fluidized furnace, can instantaneously equalize the entire temperature in the bed, prevents sintering of particles, and provides stable flow. The purpose is to

For this reason, the configuration of the fluidized firing apparatus for powder raw materials of the present invention includes a central high-speed wind pipe that blows out a high-speed airflow upward from the center of the lower part of the firing furnace to form a spouted layer in the center of the firing furnace, and a large number of a number of aeration tubes having aeration holes and installed horizontally around the central high-speed wind pipe at a position near the upper end level of the central high-speed wind pipe to form a fluidized bed around the spouted bed; a combustion furnace which is equipped with a fluidized firing furnace having a raw material input pipe for supplying powdered raw materials to the fluidized bed, and which is installed outside the fluidized bed and generates hot gas of at least the amount of heat required by the fluidized bed; , a hot gas duct for supplying the hot gas to the aeration pipe, and a low-speed wind pipe provided in communication with the lower end of the central high-speed wind pipe; It is characterized by having a hopper for taking out the clinker.

An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, 1 is a fluidized fluidized firing furnace, and 2 is the furnace 1.
5 is a central high-speed wind pipe that blows out a high-speed airflow upward from the center of the lower part of the high-speed wind pipe 2; 5 is a large number of diffuser pipes installed horizontally near the upper end level of the high-speed wind pipe 2; 4 is a raw material for supplying powder raw material to the furnace 1; Input pipe, 5 is airflow calcining furnace,
6 is a separation cyclone; 7 is a double damper; 8 is a low-speed wind pipe provided at the lower end of the high-speed wind pipe 2; 9 is a hopper provided at the bottom of the wind pipe 8 for taking out fired clinker; 10 is a clinker 11 is a combustion furnace which will be described later; 12 is its burner; 13 is a fuel supply line; 14 is its primary air fan; 15 is its secondary air line; 17 is a high-speed air supply pipe that supplies high-speed airflow to the high-speed wind pipe 2; 18 is a low-speed air supply fan that supplies low-speed air between the low-speed wind pipe 8 and the hopper 9; An air fan for cutting clinker; 20 and 21 are air fans for a cooler; 22 is a burner of the calciner 5;
23 is its heat supply line, 24 is its primary air fan, 25 is its secondary air line, and 26 is a freeboard of the firing furnace 1.

In FIG. 2, 27 is a header connecting the diffuser pipe 3 and the hot gas duct.

In FIG. 3, reference numeral 28 denotes a number of air diffuser holes formed laterally in the air diffuser pipe 3.

A powder raw material firing device configured as shown in the figure,
In this case, the powder raw material is supplied into the fluidized fluidized kiln 1 from the raw material input pipe 4. And central high speed wind pipe 2
has a classification mechanism using a high-speed air supply pipe 17 attached to the high-speed air pipe 2, a low-speed wind pipe 8 provided at the lower end, and a hopper 9. The air supplied from the low-speed air supply fan 18 is used to perform secondary classification in the low-speed wind pipe 8, and the air from both pipes 17 and 8 is combined to form a high-speed ascending airflow into the central high-speed wind pipe. Since the jet is ejected upward from the upper tip of 2, a spouted layer 29 is formed in the center of the furnace.
is formed. The hot gas supplied into the furnace from the diffuser holes 28 of the diffuser tube 3 turns into fluidized gas, and a fluidized bed 30 is formed around the spouted bed 29 . That is, in this embodiment, the entire amount of fuel required for the fluidized firing furnace 1 is completely combusted in the combustion furnace 11, and the hot gas is sent from the hot gas duct 16 to the diffuser pipe 3 via the header 27. When the gas is fed, the above-mentioned fluidized bed 30 is formed in the furnace by the hot gas from the diffuser tube 3, and the entire temperature in the bed is instantly uniformized. Therefore,
There is no local overheating in the fluidized bed 30, and particle combustion and fusion phenomena do not occur.

In this way, the clinker fired in the fluidized bed 30 circulates between the fluidized bed 30 and the spouted bed 29, and as the particle size increases and becomes heavier, it eventually becomes unable to be spouted up by the spouted bed 29, and the central high-velocity wind blows away. tube 2
It descends through the hopper 9, where the above-mentioned primary classification is performed, and then reaches the low-speed wind pipe 8, where the above-mentioned secondary classification is performed, and then passes through the hopper 9.
From this hopper 9, it reaches a clinker cooler 10, where it is cooled.

As shown in FIG. 3, in this embodiment, the air diffuser holes 28 provided in the air diffuser pipes 3 are oriented sideways, so if the distance between the air diffuser pipes 3 is too narrow, heat from the air diffuser holes 28 will be lost. Since the outflow of gas may be obstructed, an appropriate gap is provided between the diffuser pipes 3 to such an extent that the outflow of gas is not obstructed. Therefore, by providing the gap, it is possible that a part of the fired clinker will descend through the gap, so in this embodiment, as shown in FIG. The filled clinker is transported by a screw conveyor 31 and supplied to the clinker cooler 10 via an air valve 32.

As mentioned above, the present invention has a central high-speed wind pipe at the lower center of the fluidized combustion furnace and a large number of diffuser pipes installed horizontally around it, so it has two functions: a spouted bed and a fluidized bed. Moreover, since a combustion furnace that generates hot gas is installed outside and the hot gas generated in the combustion furnace is used for at least the heat and fluidization gas required for the fluidized bed, even large fluidized fluidized furnaces can avoid combustion delays. No problems occur at all, the temperature within the bed can be instantly uniformized, combustion and fusion of particles can be prevented, and stable flow can be obtained. Furthermore, since the large number of air diffusers are located near the upper end level of the central high-speed wind pipe, there is nothing that acts as a partition between the spouted bed and the fluidized bed in the combustion furnace, and both small and coarse particles are harmoniously integrated. Coupled with the ability to instantaneously equalize the entire temperature within the layer described above, it is possible to obtain uniformly fired clinker in a short time. Furthermore, since it is equipped with a low-speed wind pipe provided in communication with the lower end of the central high-speed wind pipe and a hopper provided at the lower part of the low-speed wind pipe, the fired clinker is transferred to the central high-speed wind pipe. is first classified in the hopper, and then secondly classified in the low-speed wind pipe, so that in the hopper,
It is possible to reliably obtain clinker with a precise target particle size.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention.
The figure is a front sectional view, and Figure 2 is a section line A-A in Figure 1.
FIG. 3 is an enlarged perspective view of the air diffuser. 1...Fluidized firing furnace, 2...Central high-speed wind pipe, 3...
... Diffusion pipe, 4 ... Raw material input pipe, 5 ... Air flow calciner, 6 ... Separation cyclone, 7 ... Double damper,
8...Low speed wind pipe, 9...Hopper, 10...Clinker cooler, 11...Combustion furnace, 12...Burner, 1
3...Fuel supply line, 14...Primary air fan, 15...Secondary air line, 16...Hot gas duct, 17...High speed air supply pipe, 18...Low speed air supply fan, 19...For cutting air fan,
26...Free board, 27...Hetsuda, 28...
...Diffuser hole, 29...Spouted bed, 30...Fluidized bed.

Claims (1)

[Claims] 1. A central high-speed wind pipe that blows out high-speed airflow upward from the center of the lower part of the firing furnace to form a spouted layer in the center of the firing furnace, and a large number of air diffusers near the upper end level of the central high-speed wind pipe. A fluidized firing furnace comprising a number of aeration pipes installed horizontally around the central high-speed wind pipe to form a fluidized bed around the spouted bed at a position, and a raw material input pipe for supplying powdered raw material into the firing furnace. and a combustion furnace that is provided outside the fluidized firing furnace and generates hot gas of at least the amount of heat required by the fluidized bed, and a hot gas duct that supplies the hot gas to the aeration pipe, Moreover, the powder powder is characterized by comprising a low-speed wind pipe provided in communication with the lower end of the central high-speed wind pipe, and a hopper provided at the lower part of the low-speed wind pipe for taking out the fired clinker. Fluidized firing equipment for raw materials.