JPS5911335B2 - How to modify the suspension preheater - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention replaces an existing suspension preheater such as a polyjuice type or Bedarg type that does not have a calciner in equipment for firing powder raw materials such as cement or alumina with a calciner. This article relates to a method for modifying a suspension preheater with a suspension preheater.

Traditionally, suspension kilns and suspension preheater kilns have been used extensively as firing equipment for cement raw materials, but in recent years suspension kilns with a calciner, which have a calciner installed between the rotary kiln and the suspension preheater, have been used. It has become to.

This is intended to increase the specific firing rate of the kiln by having the calciner share part of the heat load of the kiln.

In other words, in recent years, firing equipment that does not have a calciner has become obsolete, so disposing of the old firing equipment and installing a new one with a calciner would require enormous construction costs. This method requires a long construction period and is not a good idea.

The present invention reduces construction costs and shortens the construction period by modifying only a small portion of existing firing equipment that does not have a calcining furnace, and enables operation similar to newly built firing equipment. An embodiment of the present invention will be described with reference to the drawings.

Figure 1 is a front view of an existing suspension preheater without a calciner in cement firing equipment, and Figure 2 is a new suspension preheater installed to convert the suspension preheater in Figure 1 into a suspension preheater with a calciner. and a front view in which parts to be remodeled are shown with thick solid lines.

Moreover, FIG. 3 is a front view showing the state after remodeling.

First, in FIG. 1, 1 is a first distribution duct which distributes the kiln exhaust gas from the kiln inlet chamber 2 to the lowermost cyclones 3 and 3 which are symmetrically provided.

4 is a vortex chamber provided above the duct 1.

Reference numeral 5 denotes a second distribution duct which distributes the exhaust gas from the hortex chamber 4 to intermediate stage cyclones 6 and 6, which are provided symmetrically.

In addition, 7 and 7' are uppermost cyclones, 8 and 8 are cement powder raw material supply devices, and 9 is an exhaust duct connected to an exhaust fan (not shown).

Next, the first distribution duct 1 and the vortex chamber 4 of the suspension preheater shown in FIG. A calcining furnace 10 is provided.

This calcining furnace 10 includes a combustion secondary air introduction section 11 that is made up of an air chamber that introduces exhaust gas from a tarinka cooler (not shown) as secondary combustion air, and a plurality of calcining burners 1.
2.

Then, the bottom of the combustion secondary air introduction part 11 of the calciner 10 is connected to the kiln inlet chamber 2, and the positions of the inlets of the final stage cyclones 3 and 3 are changed, and the inlets and the calciner 10 are connected to each other. The upper part is connected by each descending duct 13 and 13.

Further, cyclones 14 and 14' are newly installed symmetrically on the outside and above the cyclones 3 and 3, and supported by newly installed frames 15 and 15', respectively.

The gas outlets of these newly installed cyclones 14 and 14' are connected to the second distribution duct through rising ducts 16 and 16, respectively, and the raw material outlets of the cyclones 14 and 14' are temporarily connected to raw material chutes 17 and 17', respectively. It is connected to the furnace 10, and the inlets of the cyclones 14 and 14' are connected to the gas outlets of the cyclones 3 and 3, respectively, by connecting ducts 18 and 18, respectively.

That is, the cyclones 3 and 14 on the right side are connected to the duct 18.
The left cyclones 3' and 14' are connected by a duct 18'.

Then, the suspension preheater shown in FIG. 1 which does not have a calcination furnace, that is, the existing suspension preheater, is modified into the suspension preheater with a calcination furnace shown in FIG. 3.

In constructing the calcining furnace 10, it is advisable to cut off a part of the existing first distribution duct 1 and the vortex chamber 4 and utilize the usable parts as much as possible.

It is also advisable to utilize the existing ducts associated with the vortex chamber 4 as much as possible.

In the suspension preheater with calciner modified as shown in FIG.
One flow is from the descending duct 13 → the lowest stage cyclone 3 → the connecting duct 18 → the new cyclone 14 → the rising duct 16 → the second distribution duct 5, and the other flow is from the descending duct 13 → the lowest stage cyclone 3 → the connecting duct 18 ′ → Newly installed cyclone 14 ′ → Rising duct 16 → Flows to second distribution duct 5,
After joining at this duct 5, it is divided into two parts, one of which is
One flows from the intermediate cyclone 6 to the top cyclone 7 to the exhaust duct 9, and the other one flows from the middle cyclone 6 to the top cyclone 7' to the exhaust duct 9.

The flow of the powder raw material is as follows: powder raw material supply device 8 → uppermost cyclone 7 → second distribution duct 5 → middle stage cyclone 6 → connection duct 18 → new cyclone 14 → raw material chute 17, and then the calciner 10. One more thing,
Powder raw material supply device 8'→uppermost cyclone 7'→second distribution duct 5→intermediate cyclone 6'→connection duct 18'
→ Newly installed cyclone 14' → The raw material goes through the raw material chute 17' and reaches the calcination furnace 10, where it merges and is calcined, and then splits into descending ducts 13 and 13 and reaches the final stage cyclones 3 and 3. , is fed to the kiln inlet chamber 2.

That is, in the existing suspension preheater shown in Fig. 1, the preheated powder raw material was directly supplied to the kiln inlet chamber 2, but in the modified suspension preheater with calciner shown in Fig. 3, the preheated powder raw material The powdered raw material is calcined in a calcining furnace 10 and then supplied to a kiln inlet chamber 2.

As mentioned above, the suspension preheater modification method of the present invention involves removing the existing first branch duct and vortex chamber, and using the removed space to install a vertical cylindrical calciner. Since only a small portion of the existing equipment is modified, and most of the existing equipment can be used as is, construction costs can be reduced and construction can be completed in a short period of time. .

In addition, a new cyclone was installed between the existing bottom cyclone and the cyclone above it, and a calciner was installed to partially change the flow of gas and raw materials.
As for the existing parts that will not be modified, there will be no problems at all due to the installation of the calciner.

[Brief explanation of drawings]

FIG. 1 is a front view of the existing suspension preheater, FIG. 2 is an explanatory diagram of the modified portion, and FIG. 3 is a front view of the modified state. 1...First distribution duct, 2...Kiln inlet channel, 3,3...Lowest cyclone,
4... Vortex chamber, 5...
2nd distribution duct, 6, 6'...Middle stage cyclone, 7.7'...Top stage cyclone, 8,8...
... Powder raw material supply device, 9 ... Exhaust duct, 10 ... Calciner, 11 ... Secondary air introduction part for combustion, 12 ... ...Calculating burner, 13,
13... Descending duct, 14, 14'...
・Newly installed cyclone, 15, 15... Newly installed frame,
16.16... Rising duct, 17.17'...
...Raw material chute, 18,18'...Connection duct.

Claims (1)

[Claims] 1. A first distribution duct for distributing kiln exhaust gas to the lowermost cyclones arranged symmetrically, a portex chamber arranged above this duct, and a portex chamber arranged symmetrically above the lowermost stage. a second distribution duct for distributing exhaust gas to the cyclone, and
The first distribution duct and the vortex chamber of an existing suspension preheater that does not have a calcination furnace are removed, and the vertical type has an introduction part for combustion air and a calcination burner in the removed part. A cylindrical calciner is provided, and the bottom of the calciner is connected to the kiln inlet chamber, and the upper part is connected to the inlet of each of the lowermost cyclones by separate descending ducts; New cyclones were installed symmetrically above the cyclone, and the gas outlets of these newly installed cyclones were connected to the second distribution duct through separate ducts, the raw material outlets were connected to the calciner through separate raw material chutes, and the inlets were connected to the calciner through separate chutes. A method for modifying a suspension preheater, which comprises connecting each duct to the gas outlet of the lowermost cyclone on the same side to transform it into a suspension preheater with a calciner.