JPS589828A - Heat-recovery in glass smelting furnace - Google Patents

Abstract

PURPOSE:To improve the thermal efficiency of a glass smelting apparatus furnished with a regenerator or a recuperator, by utilizing the hot exhaust gas of the glass smelting furnace furnished for the preheating of the glass raw material and the combustion air using ceramic spheres as a heat medium. CONSTITUTION:Hot gas 5 exhausted from the glass smelting furnace 1 is heat- exchanged and accumulated in the regenerator 3. A part of the gas discharged from the regenerator 3 is introduced into the ceramic sphere pre-heater 8 to the ceramic spheres used as the heat medium. A part of the heated ceramic sphere is introduced into the secondary air preheater 9 to preheat the secondary air 4. The preheated secondary air is further heated in another regenerator 2 of the smelting furnace 1, and used as the combustion air for the furnace 1. The remaining part of the ceramic spheres is utilized for the preheating of the raw material glass batch 16 in the rotary heat-exchanger 10, and returned to the ceramic sphere preheater 8. The remaining part of the exhaust gas discharged from the regenerator 8 is transferred to the glass cullet preheater 15 and utilized for the preheating of the raw material glass cullet.

Description

[Detailed Description of the Invention] Book I! The present invention relates to a heat recovery method for a glass melting furnace equipped with a heat storage chamber or a heat exchange chamber.

Conventionally, the problem with melting glass in large quantities at lukewarm temperature is the heat!
Tank furnaces with station round heat storage or heat exchanger chambers are used. Lightning-stripped heavy oil is used as fuel, and in the heat storage l1lO tank furnace, heavy oil is injected from a burner attached to the wall of the melting section in the latter half of the furnace, and is blown out from the boat. It is combusted by secondary air for the hook. The exhaust gas from the inboard boat enters the heat storage chamber, which is a heat recovery device, and heats the checker brick inside the room, and then goes to the flue,
It is released into the atmosphere after a mourning process. In a tank furnace with a heat exchanger lid, a requieperator chimney is used instead of a checker brick, and the exhaust gas is discharged into the atmosphere through a flue and an AIW after heating the secondary air. The exhaust gas discharged from the heat storage room or heat exchange room is usually 45G-6! ! Since the temperature is as low as 0°C, O heat recovery from this exhaust gas is carried out by generating and extinguishing low-pressure steam in the waste heat boiler, and the thermal energy is transferred to the system of the glass melting furnace itself. There is almost no attempt to restore it as such. Recovery of heat from such low-temperature exhaust gas is possible using equipment I! The disadvantage is that the heat collection efficiency is low compared to the conventional method.

The object of the present invention is that it was completely developed by Mr. −
It is possible to increase the film thickness of relatively simple equipment by combining the rotary heat exchanger using ceramic balls as the heating medium shown in No. 20854 Kll and the glass cullet preheating device disclosed in Japanese Patent Publication No. 49-29284. The objective is to recover heat from the exhaust gas of the glass melting furnace, and to make it possible to directly reduce and use the thermal energy generated by wAIIL for melting the girth.

The heat recovery method for a glass melting furnace of the present invention is for recovering heat from the combustion exhaust gas of a glass melting furnace equipped with a heat storage chamber or a heat exchanger, and includes a part of the exhaust gas discharged from the heat storage chamber or the heat exchanger. The other part of the exhaust gas is led to a preheating device for ceramic balls, which is circulated and used as a heat medium, and is brought into contact with ceramic balls. Cell by touching 11I)1
Preheating the ceramic bulb S: A step of introducing a part of the preheated ceramic bulb into a rotary heat exchanger and bringing it into countercurrent contact with the glass patch to preheat the glass patch; The preheated ceramic bulb Another part of the glass cullet is introduced into a secondary air preheating device and brought into contact with the secondary air. and a step of feeding the preheated secondary air into the combustion chamber of the furnace through a heat storage chamber or a heat exchange chamber.

According to the present invention, when heat is extracted from the combustion exhaust gas of a glass melting furnace equipped with a heat storage chamber or a heat exchange chamber, if the heat is passed through the preheating device described below from the middle or end of the heat storage chamber or heat exchange chamber. If you use a high-temperature secondary 9 gas, then take out the high temperature exhaust gas 11 from the overcharge, and introduce a part of it to the cullet preheating device to preheat the cullet, and heat the majority of the other part. The preheated ceramic balls are guided to a ceramic ball preheating device (moving bed heat exchanger) which is circulated as a medium, and are exchanged countercurrently with the ceramic balls that descend at a constant screen rate, and the preheated balls are discharged from the preheating device. The flow of the two ceramic spheres is divided into two, one of which is guided to the rotary heat exchanger to preheat the raw material patch, and the other is guided to a secondary air preheating device (a moving bed type similar to the two ceramic sphere preheating device). By introducing the heat exchanger (heat exchanger cover) and exchanging heat with the secondary air at room temperature, the secondary air, which conventionally was sent to the heat storage chamber without being preheated, is preheated and the boat heats up. increases the final temperature of the secondary air blown into the combustion space of the furnace from the
This increases the temperature of the exhaust gas discharged from the heat chamber, allowing for more efficient heat exchange.

In general, the water equivalent of the exhaust gas from a glass melting furnace is sufficiently larger than the water equivalent of the raw material (patch 10 cullets) (including the amount of heat required for crystallization water and the latent heat of vaporization of water), so the unit is If the volume of the exhaust gas and the circulating weight of the ceramic bulbs are appropriately distributed to each heat exchange device, it is possible to raise the temperature of not only the raw material but also the secondary air to a predetermined temperature. Focusing on the above rotary heat exchange equipment,
Previously proposed methods for preheating glass raw materials using exhaust gas require initial investment due to larger equipment lids, increased maintenance costs, contamination of raw materials, segregation of raw materials, and 110m exhaust gas treatment facilities [the various drawbacks of Misaka Misaki] By solving all of these problems, we were able to complete a compact and highly efficient waste heat collection system using nine exhaust gases.

The details of the present invention will be explained with reference to the schematic cross-sectional views of each device in the 70-sheet of FIG. 1, S2, and S of FIG.

FIG. 1 shows a 70-sheet for implementing the invention in a glass melting furnace with a side boat type regenerator.

In the figure, 1 indicates the melting tank of the glass melting furnace [1, 2, and 5 #'i indicates the heat storage chambers provided on both sides of the furnace.

Secondary air is supplied to the combustion space in the upper part of the four-layer melting tank through the heat storage chamber 2, and 5 indicates the combustion exhaust gas discharged from the combustion space through the heat storage chamber 3.

6 and 7 indicate exhaust gas and secondary air exchange valves.

The exhaust gas S#i passes through the heat storage chamber 3) and enters the ceramic bulb preheating device 8 via the exchange valve 6, where it comes into contact with the ceramic bulb and preheats it. The cellar two-ball preheating device 8 is a single moving bed heat exchange device as shown in Fig.
1, ceramic balls at a temperature of 70 to 150°C are supplied quantitatively and successively fall downward. -1 The exhaust gas 5 discharged from the heat storage device 5 is 1. The exhaust gas is introduced into the device through the inlet 22 provided in the middle of the device, and is brought into contact with the ceramic bulb in countercurrent @L2, and then heated to a desired temperature, usually SOO ~ 70°C.
Preheating is performed at 0''Ct. The preheated ceramic sphere is discharged from the apparatus through the ceramic sphere outlet 23 at the bottom of the apparatus.

-1 exhaust gas is cooled to 120 to 2001 m: and is sucked into the fan 14 from the exhaust gas outlet 24 to reach the acls.

The secondary air is sucked in by 4 77 tons of room temperature secondary air 13.
Enter the air preheating device 9. The secondary air preheating device 9 is a moving bed type heat exchanger lid similar to the ceramic ball preheating device 8, and the preheated cellar 2 discharged from the ceramic ball preheating device 8 is used as a secondary air preheating device 9.
The pick ball enters the device through the input port 25 at the top and falls toward the outlet 27 at the bottom. Secondary air enters through the inlet 26 and contacts the ceramic sphere countercurrently to a desired temperature typically 15
0 to 2501: preheated to outlet 28] Exchange valve 7
It then enters heat storage chamber 2. Since the secondary air is preheated in this way, the temperature of the exhaust gas also rises, and the temperature of the exhaust gas at the outlet of the heat storage chamber 3 is 450 to 60℃ when room temperature air is used.
While it is 50°C, it ranges from 40fl to 800°C.

15 indicates the glass cullet 1A O preheating charge, which is W
llIO moving bed heat exchanger, upper input port 2! Glass cullet is introduced into the chamber and discharged from the outlet 31 at the bottom. On the other hand, a part of the exhaust gas from the heat storage IIS contacts the gas inlet 30 of the device countercurrently with the internal glass cullet 17, preheating the cullet to about 450 to 550°C.
After 7 hours, the exhaust gas exits from the exhaust gas outlet 32 and heads toward the chimney 18. The glass cullet is sent to a preheated glass cullet 2 xer 19.

10 is a rotary heat exchanger described in detail in Japanese Patent Application No. 56-20854. Glass patch 16 is sent from patch hopper 11 to screw feeder S5)!
1! One end of the station is sent to the Myoki station. Meanwhile, preheated ceramic spheres 12 are fed into the apparatus by a screw feeder 54 at the other end of the apparatus. The device is #l311
As shown in FIG. 1, a cylindrical outer tube 35 and an inner wall having a mesh structure that is surrounded by the outer tube K and rotates integrally with each other are provided.
By rotating the inner cylinder and the outer cylinder, the ceramic sphere is advanced toward the other end of the inner cylinder, and the glass patch is passed through the mesh of the inner cylinder to pass between the outer cylinder and the inner cylinder. Move it in the opposite direction to the two dragon balls. Therefore, the inner cylinder has a screw blade @sy inside E2, and the inner cylinder rotates KfP to advance the ceramic sphere. On the other hand, the glass patch is 111m towards the exit of the patch! It moves by tilting and rotating.

Additionally, there is a space between the outer cylinder and the inner cylinder that is +'
A plurality of segment plates 3B are provided to support the inner cylinder, and as the outer cylinder rotates, the glass patches in each partition chamber partitioned by the segment plates sequentially fall into the inner cylinder. It comes into contact with the ceramic bulb and is preheated.

The ceramic sphere, preheated to about 500-700°C, contacts the glass patch and preheats the tube to 400-600°C. As a result, the temperature of the two-seater ball has dropped to about 100℃, and the ball is ready for exit 5! 1) ill? The raw material cullet is sent to the glass melting furnace 19, where it is heated and charged with glass cullet, and then fed into the raw material hopper 20 provided in front of the input port of the glass melting furnace.

〔Example〕

When manufacturing bottle glass by the conventional method in a side-port type heat storage glass melting furnace with a metal body capacity of 200'/, the amount of heavy oil used is S2'/, and the glass withdrawal amount is 2.
00 'r/D) Glass 1 - The amount of heavy oil used in Todoroki is 1
It was 60 tons.

In a glass melting furnace under such conditions, a heat recovery device was attached according to the method of the present invention, and glass was made into a glass melting furnace.

Exhaust gas at approximately 650℃ at the outlet of the heat storage chamber 14,00ONdlH
Of these, 12.100 Md1M t ceramic sphere preheating device, 1,90ON 4 was guided to the glass cullet preheating device, ceramic ball with circulation volume 14.80047'+, glass cullet with processing amount 2.5004/H and heat. The temperature of the ceramic bulb was raised from 100°C to 600°C, 600°C to 500°C. The temperature of the exhaust gas drops to 15g1℃ and rises to 6600℃.・11 Kp/H is guided to the rotary heat exchanger, 400 yen is guided to the secondary air preheating device, and the throughput is 7. S OOKv'F10 patch 50° → 50
0℃, 1zsooNII//u secondary air sO → 2
It was possible to raise the temperature to 00°C. On the other hand, the temperature of the ceramic bulb was lowered from 400°C to 100°C, and a circulation system was constructed in which it was discharged and returned to the preheating device. The ceramic ball used is an average ball @9-O→ra ball. As a result of raising the secondary air temperature to 200°C, it is possible to raise the exhaust gas temperature, which is normally SaO°C, to the above-mentioned 450 tl, increase its sensible heat, and perform efficient heat exchange.

It was found that when the glass melting furnace was operated continuously under the above conditions, the amount of heavy oil used was reduced to 2 & y Jl/D in order to maintain a glass draw-out amount of 20 OV in a steady state. The amount of heavy oil used (fuel consumption rate) for the glass 1t6n Todoroki is 1ssst.

Table 1 shows the above operating conditions and results in comparison with the conventional method as an example.

1! -1 Glass patch preparation using the @ rotary heat exchanger of the present invention
Thermal system 041 color is as follows).

(1) From the exhaust gas and raw material om*@x (compared to the direct contact method) 1) There is no deterioration of the raw material or separation.

The deterioration of the raw material can be avoided by selecting a material for the heat medium, the cera 2 ivy bulb, that is a part of the raw material components or one that is similar to the heat exchanger.

2) #Complicated gas processing can be avoided.

Even with the direct contact method, the packed bed method in which the raw material patch is pelletized has no intervening layer and the equipment is relatively compact), but the cost of the pelletizing equipment and maintenance in the previous stage is high, and it is difficult to introduce water into pellets. This amount results in heat consumption during preheating.

In the general direct contact method, patch fine powder is scattered in a large amount of exhaust gas, and the entire amount of exhaust gas cannot be sent to the exhaust gas section equipment unless it is Ikl [Ikl] in the final stage.

(2) It is a kind of indirect contact method, but compared to other indirect contact wheels, 1) It is a kind of ## contact method, but it is a two-stage direct contact method between the exhaust gas and the ceramic ball, and the ceramic ball and the patch. It can also be said to be a direct contact method.

Making the diameter of the two spheres uniform and making the shape spherical
Yoshisera 2-Tsuku ball preheating device O suppresses the increase in pressure loss and 1
If you have a large direct contact area with exhaust gas,
) Improves heat exchange efficiency and requires only a combination of equipment.

For single-turn heat exchange scissors, there are two Cera bulbs! ! Due to the large area and high heat exchange efficiency due to the raw material and O countercurrent flow, direct flow, and repetition *@, the Yabari equipment becomes compact.

Therefore, compared to the conventional lIJ**@ method, even with two stages, it is more compact and has higher heat exchange efficiency.

[Brief explanation of drawings]

slm is a 70-sheet explaining the direction of the present invention, Diagram 2 is a cutaway diagram of the apparatus used in the method of the present invention, and Figure 3 is a 92-sheet.
The A-A' section of the figure is shown. 1... Melting tank 2.3... Heat storage dust 4
...Secondary air 5...Exhaust gas6.
7... Exchange valve 8... Ceramic bulb preheating device 9... Secondary air preheating device 10... Single transfer heat exchanger

Claims (1)

[Scope of Claims] (1) To remove heat from the working exhaust gas of a glass melting furnace equipped with a heat storage chamber or heat exchanger, and to convert a part of the exhaust gas discharged from the heat storage chamber or heat exchanger into glass. The other part of the exhaust gas is introduced into the cullet preheating device and brought into contact with the cullet F, and the other part of the exhaust gas is introduced into the preheating device for the ceramic balls used as a heat medium, and the cullet is brought into contact with the cullet F. II. Preheating the ceramic sphere by touching it;
'A part of the preheated ceramic bulb is introduced into the rotary heat exchanger IIIlllI and the glass batch is counter-currently heated.
A process of preheating the ballast patch by tightening the shaft; A process of introducing a part of the preheated ceramic bulb into the secondary air preheating device and bringing it into contact with the secondary air to preheat the secondary air. feeding the preheated glass cullet and the preheated glass batch into a glass melting furnace l1; and feeding the preheated secondary air into the combustion space of the furnace through a heat storage chamber or heat exchanger. A heat recovery method for a glass melting furnace that does not involve any process. (Kon) The glass cullet preheating device is a moving bed type O heat exchange device, and the glass cullet is supplied,
Patent-requested range m 1 in which exhaust gas is fed downward, and the glass cullet in the straw rack comes into contact with the exhaust gas countercurrently and is preheated.
The method described in section. (3) The preheating device for the ceramic balls is a moving bed heat exchanger, and the ceramic balls are supplied from above the device and descend at a constant speed. Claim lI No. 1, which is preheated by contacting countercurrently with
The method described in section. ■ The secondary air preheating device is a moving bed heat exchange device, and the secondary air introduced from below the device comes into countercurrent contact with preheated ceramic spheres supplied from above the device and descending. 2. A method according to claim 1, wherein the method is preheated. (5) The single-transformer heat exchange device includes a cylindrical outer cylinder;
This is composed of an inner wall having a side wall of a mesh structure that is surrounded by the inner wall and rotates integrally, and a ceramic bulb, which is a preheated heat medium, is supplied from one end of the inner wall, and a glass patch is supplied from the other end of the inner wall. is supplied, and by rotating the inner tube and the outer tube, the ceramic sphere is advanced toward the other end of the inner tube, and the glass patch is passed through the mesh of the inner tube to connect the outer tube and the inner tube to the ceramic sphere. The method according to claim 1, wherein the ball is moved in a direction opposite to the ball. (&) The above-mentioned details include cleaning the screw blade inside, stopping the rotation of the inner cylinder to advance the two cera balls, and separating the outer cylinder in the radial direction between the front outer ring and the inner cylinder. A patent in which a plurality of segment plates are provided, and the scissors segment plate supports the inner cylinder, and along with the surrounding plate of the outer cylinder, the glass patches in each partition chamber partitioned by the segment plates are sequentially dropped and supplied into the inner cylinder. The method according to claim 5.