JPS63163782A - Heating-temperature control method and device for forced combustion type gas kiln - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention relates to a method and device for controlling the heating temperature of a forced combustion type γ-stooth kiln. The application field is type gas windows.

(Prior art) As shown in Fig. 5, a forced combustion gas flame is blown from a burner r placed on the side surface of the lower part of a container a filled with objects to be heated such as ceramic products, and the gas flame is sent to the ceiling of the container. In this forced-burning forced combustion gas kiln 1, where the flame is blown up and discharged from the chimney e through the exhaust port d provided in the kiln floor C, the temperature of the ceiling and the temperature of the kiln floor C are equal to each other in the initial stage of heating. Create a gradient and average the temperature distribution inside the mold (requires two hours).

Figure 6 shows temperature measurement sensors installed in the ceiling part "Top A" and the kiln floor part "Root B" for the forced combustion gas furnace A using mold volume 4P and LP7yx in Figure 5. In order to suppress the temperature difference between "Ten A" and "Root B" as much as possible, the first 2 hours of the head are set to 50 + a / m A q according to the gas pressure scale P (+a / 1 IIAq) shown on the vertical axis on the right side of the figure. After the elapsed time, increase the pressure stepwise as shown in the figure to 7.5
After 8r, increase the maximum pressure to 450 to/'+a
With the fuel supplied to
This is a graph showing the results of measuring the temperature rise over time for "Root A" and "Root B". After one hour of heating, the temperature of "Ten A" rose to 440"C, but rm B J was 260 degrees Celsius, which already caused a temperature gradient of about 180 degrees Celsius. After that, the temperature gradient continued, and "Ten A" rose to 440"C. ”
It took about 9 hours for "Root B" and "Root B" to reach almost the same temperature and that there was almost no temperature gradient. The graph in Figure 6 shows that even if there is a temperature gradient between "Top A" and "Root B", net firing is possible fl1
8, and the gas supply amount was maximized after 7.5 hours, but the temperature of "Heaven A" was 1120℃.
After that, it takes 2 hours to further raise the core temperature to 1230°C, and the amount of gas required is 173.8 kg, assuming that the firing time is until the temperature gradient is almost eliminated.
(8Hr), the amount within the baking time is 60.5Kg (2
Hr), total usage i was 234.3 Kg (10 tlr).

(Problems to be Solved by the Invention) The problems to be solved by the present invention are to reduce gas consumption and shorten time. In other words, if the temperature gradient between "Ten A" and "Root B" is large as shown in Figure 5, the time required for the insect to almost eliminate the temperature gradient will increase, and the amount of gas consumed will also increase in proportion to that time. do. Conventionally, this has been overlooked as a matter of course, but the present invention aims to take this point into account and develop a method and device that can shorten the required time as much as possible and also reduce gas consumption. .

(Means for Solving the Problems) The present invention aims to solve the problems described in succession, and the first invention is to provide forced combustion from a burner disposed on the lower side of the kiln. A gas flame is blown into the kiln, the gas flame is blown up into a natural valve, and the gas flame is discharged into the chimney through a wandering flame opening in the kiln floor. The present invention relates to a heating temperature control method for a forced combustion gas kiln characterized by adding flame diluting gas such as outside air or exhaust gas that acts to weaken the buoyancy of the gas.

The second invention is characterized in that the combustion flame blowing burner disposed below the forced combustion double-flame gas kiln is provided with a blowing pipe for diluting gas such as outside air or exhaust gas to suppress the buoyancy of the blown gas flame. This relates to a temperature control device for a forced combustion gas kiln.

A preferred embodiment of the invention will now be described.

(Example) Figures 1 to 3 show an example of the invention of tJJ2 of the present invention,
Figure 1 shows the second invention applied to the forced combustion gas cylinder of the falling type.
2 is a side view of the same, and FIG. 3 is a longitudinal sectional view of a part of another embodiment.

A gas burner 8 is inserted into each of the gas flame blowing holes 2 arranged horizontally and vertically at the bottom of both sides of the kiln 1, and inside the chamber 3,
A large number of flame passageways 4 are provided which communicate with the rear chimney 7, and a large number of flame openings 5 are provided on the upper surface of the chimney 3, which communicate with the flame passageways 4. A gas flame abutting wall 6 is provided low between the upper surface of the gas flame and the upper surface of the gas flame.

A gas supply pipe 9 and an air supply pipe 10 whose supply amount is controlled by a blower 11 are connected to the gas burner 8 outside the gas furnace 1 .

The second invention of the present invention is the above-described known mold configuration,
Pass the exhaust gas return W12 inside the chimney 7, and connect the return pipe 1
A sirocco fan 13 is interposed in the gas flame inlet 2, and the tip of the exhaust gas return pipe 12 is opened at the outer periphery of the tip of the gas flame outlet of the burner 8 inserted into the gas flame inlet 2. The exhaust gas return pipe can be passed through the inside of the gas burner 8, and its tip can be opened as shown by the chain line in FIG.

The amount of exhaust gas sucked into the exhaust gas return pipe 12 is determined by a manually operated cock, and flame dilution gas is blown into the kiln. The temperature of the blowing is 700-500''C.

In Baiji, instead of the exhaust gas return pipe 12, an independent outside air blowing pipe 14 can be provided as shown in FIG. Outside air intake W14
The temperature of the flame dilution gas blown in is 15℃~25℃
It is.

A first aspect of the present invention performs heating temperature control using the wires illustrated in FIGS. 1 to 3.

(Effect) Figure 4 is! @Using the kiln illustrated in Figure 3 (see Figure tlS1), pack the dried dough for the 3-industry fired product as usual, and install temperature measurement sensors on the "Ten A" and the kiln floor part "Root B". , the gas pressure i shown in the vertical pongee on the right side of the figure is based on the trial fa error.
According to P(+a/mΔq), the supply pressure of diluted outside air and LPf
This is a graph of the measurement results obtained by formulating the correlation ratio of the supply pressure of f gas and applying the heating temperature control of the first invention based on the outside air supply shown by the 7α line and the LP >5" large supply shown by the solid line. Since Fig. 6 is a graph of combustion control performed with the outside air blower 9'14 of Fig. 3 (see Fig. 1) closed, the graphs of Fig. PlfJ4 and Fig. 6 can be compared with each other. Figure 7 shows the heat curve in Figure 4 and the heat curve in Figure 6 to clarify this contrast.
This is a graph that is also shown with the heat curve in the figure to facilitate comparison.

The first invention of the present invention shown in the graph of FIG.
The supply pressure for elf is set to 65I++/mAq, which is slightly higher than the supply pressure in Figure 6 at the beginning of the IHr, and then increases the subsequent IHr to 100m/m^q, and further increases the pressure by 0.5) (r). However, after the passage of 6.OHr, the gas supply pressure is increased to 6.
00 +n / +n At the same time as 8q, external air, which is flame dilution gas, is supplied from the beginning, and the supply is stopped after 6.58r, when the thermal gradient between "Heaven A" and "Root B" disappears, and combustion begins. This shows the results of combustion control that uses a gas flame to perform net firing.The combustion gas flame contains a flame diluting gas (outside air) that lowers the temperature of the flame and weakens the buoyancy of the gas flame. is added, the temperature of the flame decreases, the buoyancy of the gas flame is weakened, and the total amount of gas flame that reaches the sky AJ is suppressed, and a portion of the gas flame heats up by the time it rises to the sky Δ. Due to the gap force caused by stuff being packed together, things fall to “root B”,
The heat curve of "Ten A" shown by the solid line and the "Root B" shown by the dotted line
"The temperature gradient of the heat curve can be maintained at around 50°C, and the temperature gradient can be reduced to zero after about 6.58r, and the average mold temperature at that time is 1120'C-11.
It is clearly shown that the amount of gas flame blown into the first half and second half of the preliminary firing, which is carried out by increasing the mold temperature to 1230°C after sowing, can be maintained larger than that shown in the graph of FIG. 6. The amount of gas required is 161.9kg (6,58r) if the firing time is until the temperature gradient disappears, and the amount during the warming time is 32.4kg (IHr).The total amount used is 194.3k.
g (7,58 r), and the amount of diluent gas (outside air) supplied during the combustion time was 44,358 g (6,58 r). Below is a table that makes the comparison clear.

(Note) "Amount of firing gas" is the amount of gas consumed during firing time. "Nursing γ gas amount" is the amount of gas consumed during the counting time.

Figure f54 is a graph illustrating the effect of the first aspect of the present invention, and the effect of the present invention can be inferred from this graph.

(Effect) The first aspect of the present invention is to add flame diluting gas such as outside air or exhaust gas to the gas flame blown from the burner into the inside of the kiln, which acts to lower the temperature of the gas flame and weaken the buoyancy of the flame. However, this method suppresses the rise of flame gas to the ceiling and allows some of it to pass through the objects to be fired on the kiln floor during its rise and fall to the kiln floor. Even if it is sent, the gas flame lowers the flame temperature and weakens the buoyancy.
Unlike the conventional heating method, which raises the temperature of the ceiling and then uses the heating power to heat the kiln floor, the heating temperature of the kiln floor is low and does not cause an obvious temperature gradient, but only a slight temperature gradient occurs. However, since it is possible to perform almost ideal combustion control that averages the mold temperature early in terms of time, even if a large amount of combustion gas is blown in from the beginning of heating and the combustion consumption is increased, As a result, the time taken until the temperature gradient disappears is shortened, which results in a reduction in fuel consumption.In addition, it is possible to reduce the amount of gas injected into the flame gas at the beginning of the firing process and at the end of the temperature gradient elimination process. Since it can be maintained, there is no risk of new temperature gradients occurring, and the effect of shortening the heating time and improving the operation rate of the kiln, as well as the effect of saving fuel, can be fully realized by mold heating temperature control. It's something you get.

Further, the second invention has a configuration in which a diluent gas blowing pipe for lowering the temperature of the blown gas flame and suppressing the buoyancy of the flame is opened on the outer periphery of the burner for blowing the combustion flame into the gas burner.
This has the effect of simplifying the dyeing pattern and facilitating the implementation of the f51 invention.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional front view of a forced combustion type gas kiln according to the second invention of the present invention, Fig. 2 is a side view of the same, and Fig. 3 is a partial longitudinal sectional front view showing another embodiment. Figure 4 is a graph showing the heat curve of the second invention of the present invention, and also shows the supply curves of combustion gas and flame dilution gas. 6 is a graph showing a conventional heat curve under control of the heating temperature iIJ, and FIG. 7 is a graph showing the supply pressure of combustion gas as well. 7 is a graph showing both the heat curve of the graph and the heat curve of the conventional method shown in FIG. 6. 1 → Kiln 2 → Gas gas inlet 3 → Kiln floor 4 → Wandering flame path 7 → Chimney opening 8 → Gas burner 12 → Wandering gas return pipe 14 → Outside air blowing pipe procedure amendment 1. Description of the case Japanese Patent Application No. 61-817782, title of the invention Heating temperature control method and device for forced combustion gas kiln 3, person making the amendment Relationship to the case Applicant name Niimi Sangyo Co., Ltd. 4, agent (3) On page 6, line 11 of the specification, the phrase "temperature control device" is corrected to "heating temperature control device." Japanese Patent Application No. 61-81778 Attachment Claims 1) Forced combustion gas flame is blown from a burner placed on the side of the lower part of the kiln, and the gas flame is blown up to the ceiling through a wandering flame opening provided on the kiln floor. In the case of an overturned gas type that is discharged into the chimney, flame diluting gas such as outside air or exhaust gas is added to the gas flame blown into the kiln from the burner to lower the temperature of the flame and weaken the buoyancy of the gas flame. A heating temperature control method for a forced combustion gas kiln. 2) A combustion flame blowing burner placed below the forced combustion double-flame gas kiln is equipped with a blowing pipe for diluent gas such as outside air or exhaust gas that lowers the temperature of the blown gas flame and suppresses the buoyancy of the gas flame. A heating temperature control device for a forced combustion gas kiln characterized by being provided with an open opening. Procedural amendment

Claims (1)

[Claims] 1) A forced combustion gas flame is blown from a burner placed on the lower side of the kiln, the gas flame is blown up to the kiln ceiling, and is discharged into the chimney from a flame exhaust port provided on the kiln floor. In a type gas kiln, a forced combustion type gas kiln is characterized by adding flame diluting gas such as outside air or exhaust gas to the gas flame blown into the kiln from the burner, which lowers the temperature of the flame and weakens the buoyancy of the gas flame. How to control the heating temperature of a gas kiln. 2) A blower pipe for blowing diluent gas such as outside air or exhaust gas to lower the temperature of the blown gas flame and suppress the buoyancy of the gas flame is installed in the combustion flame blowing burner placed below the forced combustion type upside down gas kiln. A temperature control device for a forced combustion gas kiln characterized by being installed in an open state.