JPS6344665Y2 - - Google Patents

Description

Detailed Description of the Invention Industrial Applicability Field The present invention relates to an improvement in a liquid fuel combustion device having a combustion system for feeding two types of liquid fuel with different viscosities, and combusting each liquid fuel in a common burner.

BACKGROUND TECHNOLOGY As shown in FIG. 3, a conventional liquid fuel combustion device of this type has a feed line 1 of a combustion system A (hereinafter referred to as system A) that feeds a high viscosity liquid fuel 14 and a low viscosity liquid fuel 14. The feed line 2 of the combustion system B (hereinafter referred to as system B) that feeds the liquid fuel 15 is the burner 7.
When only the liquid fuel 14 is to be used for combustion, the burner inlet valve 5 that controls the liquid fuel 14 is fully opened, the burner inlet valve 6 that controls the liquid fuel 15 is fully closed, On the other hand, when only the liquid fuel 15 is to be used for combustion, the operations described above are reversed.

Then, either the liquid fuel 14 or the liquid fuel 15 is supplied by a liquid fuel pump (not shown).
They are fed under pressure through a feed line 1 and a feed line 2, respectively, and are adjusted to a predetermined pressure by a pressure regulating valve 3 of a system A and a pressure regulating valve 4 of a system B, respectively, and then injected from a common burner 7 into a furnace (not shown). It is now ready for burning.

In addition, 8 is a pressure detector for the liquid fuel 14 of system A, 9 is a pressure detector for the liquid fuel 15 of system B, 10 is a pressure transmitter for the liquid fuel 14 of system A, and 11 is a system 12 is a regulator for the liquid fuel 14 of system A, and 13 is a regulator for the liquid fuel 15 of system B.

However, in such conventional liquid fuel combustion systems A and B, the liquid fuel 14 and the liquid fuel 15 are not simultaneously flowed and used for combustion, except for a temporary period when switching fuels. In addition, the fuel flow rate is adjusted by detecting the pressure upstream of the confluence of the liquid fuel 14 feed line 1 and the liquid fuel 15 feed line 2, and adjusting the liquid fuel flow rate by the pressure control valve 3 or the pressure control valve 4. The pressure is automatically adjusted to maintain a predetermined flow rate.

In such a conventional liquid fuel combustion device, when two types of liquid fuels having a large difference in viscosity are switched and burned, the high viscosity liquid fuel 14 is burned in the burner 7.
The passage resistance up to the outlet is large, and in order to maintain the same flow rate as the liquid fuel 15, the pressure setting value described above needs to be higher than in the case of the liquid fuel 15.

Figure 4 shows an example of a flow rate characteristic diagram obtained by separately injecting commercially available heavy oil H and a coal-oil mixture (hereinafter abbreviated as COM) using the same burner.

From Figure 4, the flow characteristics of the two are different, especially in the region of large flow rates, and heavy oil H, which has a low viscosity, has a high viscosity.
Compared to COM, the rate of increase/decrease in the flow rate with respect to the increase/decrease in the burner 7 inlet pressure is large, and the absolute value of the flow rate is also large.

As mentioned above, this is because the higher viscosity COM has a higher passage resistance in the burner. In order to maintain the same flow rate as heavy oil H,
It is necessary to inject the COM at higher pressure.

Problems to be solved by the invention As a result, in the conventional liquid fuel combustion device, a)
When two types of liquid fuels with large differences in viscosity are used, the pressure on the feed line 1 side of the high viscosity liquid fuel 14 is adjusted to be higher than that on the feed line 2 side of the low viscosity liquid fuel 15. When switching to high viscosity liquid fuel 14 during combustion of viscous liquid fuel 15, low viscosity liquid fuel 15 is added to the fuel feed line.
While this remains, the rapid pressure rise causes the fuel flow rate to become excessive, causing combustion deterioration. b),
When liquid fuels with extreme viscosities are used in the same burner 7, the capacity of the burner 7 is planned to be suitable for the liquid fuel 14 with a high viscosity that is difficult to flow. Therefore, for low viscosity liquid fuel 15, the burner 7 has an excessive capacity, which has drawbacks such as making flow rate control very difficult.

The present invention was devised in view of and to solve the problems of the conventional technology, and it provides stable and easy fuel switching when two types of liquid fuels with different viscosities are shared in the same burner. enable,
Moreover, it is an object of the present invention to provide a novel liquid fuel combustion device equipped with a liquid fuel fuel system whose flow rate can be easily controlled.

Means for Solving the Problems In order to achieve this objective, the liquid fuel combustion device of the present invention is equipped with a combustion system that feeds two types of liquid fuels with different viscosities, and a common burner is used to feed each liquid fuel. In a liquid fuel combustion device that burns fuel, a resistor is provided in the low viscosity liquid fuel line just before the high viscosity liquid fuel line and the low viscosity liquid fuel line join, and the pressure is taken out for the pressure control valve of the low viscosity liquid fuel line. It is characterized in that the relationship between the partial pressure and the flow rate of the low viscosity liquid fuel is configured to be the same as that of the high viscosity liquid fuel line.

Embodiments The present invention will now be described in detail with reference to illustrative embodiments.

In FIG. 1, a combustion system A is shown in which one feed line 21 at the starting end branches into four lines at the end and is connected to each of the four burners 27 in order to feed high viscosity liquid fuel 34. , consists of a combustion system B in which one feed line 22 at the starting end branches into four lines at the end and is connected to each of the burners 27, respectively, in order to feed low viscosity liquid fuel 35; A resistor 3 is connected to the feed line 22 of the combustion system B side of the low viscosity liquid fuel 35 immediately before the respective feed lines 21 and 22 of the combustion systems A and B merge on the side.
There are 6. The resistor 36 is constructed by selecting the passage area of the feed line 22 so that the flow characteristics of both fuels are equivalent when the burner 27 has a planned flow rate, based on the above-mentioned FIG.

In Fig. 1, 23 is a pressure control valve on the side of combustion system A (hereinafter referred to as system A), and 24 is a pressure control valve on the side of combustion system B.
(hereinafter referred to as system B) side pressure control valve, 25 is the burner inlet valve on the system A side, 26 is the burner inlet valve on the system B side, 28 is the pressure detector on the system A side, 29 is the pressure on the system B side Detector 30 is a pressure transmitter on the system A side, 31 is a pressure transmitter on the system AB side, 32 is a regulator on the system A side, and 33 is a regulator on the system B side.

In FIG. 1, the burner inlet valve 25 on the system A side is fully closed, and the burner inlet valve 26 on the system B side is fully closed.
When switching the high viscosity liquid fuel 34 to the low viscosity liquid fuel 35 by fully opening the pressure control valve 2 of the low viscosity liquid fuel 35 feed line 22,
The relationship between the pressure of the pressure detection unit 4 and the flow rate of the liquid fuel 35 becomes equivalent to that of the high viscosity liquid fuel 34 in the feed line 21.

FIG. 2 shows experimental results regarding the flow rate characteristics of heavy oil H and the flow rate characteristics of COM when a resistor 36 is provided in the feed line of heavy oil H.

The resistor 36 is connected to the burner 2 based on the above-mentioned FIG.
The passage area was selected so that the flow characteristics of both fuels would be the same at the planned flow rate of 7, and as shown in Figure 2, the flow characteristics of heavy oil H and COM match well up to the low load region.

Effects of the invention As described above, in the liquid fuel combustion device of the invention,
By installing an appropriate resistor in the low-viscosity fuel line, even when two types of fuel with large viscosity differences are used in the same burner, it is possible to equalize the flow characteristics of both fuels, resulting in a low-viscosity fuel line. Switching to high viscosity fuel during fuel combustion is smooth, and flow rate adjustment is also easy.

[Brief explanation of the drawing]

Figure 1 is a schematic diagram of the liquid fuel combustion device of the present invention.
Figure 2 is a chart showing the relationship between fuel flow rate and pressure in the above combustion device, Figure 3 is a schematic diagram of a conventional liquid fuel combustion device, and Figure 4 is a chart showing the relationship between fuel flow rate and pressure in the same combustion device. be. 21...High viscosity liquid fuel line, 22...Low viscosity liquid fuel line, 27...Burner, 34...High viscosity liquid fuel, 35...Low viscosity liquid fuel, 36...
...Resistor.

Claims (1)

[Scope of utility model registration request] In a liquid fuel combustion device that is equipped with a combustion system that feeds two types of liquid fuels with different viscosities and burns each liquid fuel in a common burner, immediately before the high-viscosity liquid fuel line and the low-viscosity liquid fuel line merge. A resistor is installed in the low viscosity liquid fuel line of
A liquid fuel combustion device configured such that the relationship between the pressure at a pressure outlet for a pressure control valve of a low viscosity liquid fuel line and the flow rate of the low viscosity liquid fuel is the same as that of a high viscosity liquid fuel line.