JPS6255567B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of spraying a fuel consisting of pulverized coal, water and oil.

Mixing pulverized coal with oil such as heavy oil and burning it while atomizing it with a spray burner increases the calorific value and reduces the amount of oil required, which is attracting attention from the perspective of energy conservation. The problem with such oil containing pulverized coal is that the adjusting device for such oil fuel containing pulverized coal is abraded by the highly hard pulverized coal and is damaged early.

In addition, in oil fuel containing pulverized coal, the pulverized coal must be uniformly dispersed in the oil, and if such uniform dispersion is not achieved and some parts settle, it may cause combustion spots. Otherwise, the nozzle of the spray burner may become clogged. In order to improve the dispersion of pulverized coal in oil, there are two methods: adding an expensive dispersant and mixing water into an emulsion state without using such a dispersant. It is more advantageous than the former because water acts to promote combustion. However, even with such dispersants or emulsions,
There is a problem in that it is not always possible to completely prevent pulverized coal from settling.

The purpose of the present invention is to solve the above-mentioned problems with oil fuel containing pulverized coal, to effectively activate water-in-oil type emulsion fuel, to suppress damage to emulsion fuel adjustment equipment, etc. caused by pulverized coal, and to prevent damage caused by pulverized coal sedimentation. It is an object of the present invention to provide a method and device for spraying fuel consisting of pulverized coal, water and oil, which prevents combustion spots and nozzle clogging of a spray burner from occurring.

The method of spraying a fuel consisting of pulverized coal, water, and oil according to the present invention achieves the above object, after preparing a water-in-oil type emulsion fuel, when spraying the emulsion fuel from a spray burner, immediately before the spray burner. At the position, a mixture of pulverized coal and oil is injected into the emulsion fuel, and the pulverized coal, water and oil are uniformly mixed and dispersed by a motionless mixer, and then in the uniformly mixed and dispersed state. It is characterized by being immediately sprayed from the spray burner.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically explained below using embodiments shown in the drawings.

FIG. 1 shows a schematic diagram of a device for carrying out the method of the present invention, in which 1 is a water-in-oil emulsion fuel conditioning device, 2 is a pulverized coal and oil mixing device, and 3 is a spray burner. be. The water-in-oil type emulsion fuel adjustment device 1 has a motionless mixer 4 as its mixing means.Oil O is supplied to the motionless mixer 4 by a pump 5, and water W is supplied to the motionless mixer 4 by a pump 6. are now being supplied. The oil O may be preheated by the heater 7 before being supplied to the motionless mixer 4 by the pump 5.
Reference numerals 8 and 9 are flow meters for the pumps 5 and 6, respectively, and the flow signals from the flow meters 8 and 9 are used to control the amount of oil and water supplied to the pumps 5 and 6 through the control panel 10 so that the mixing ratio is constant. controlled by. The motionless mixer 4 is a so-called static mixer that does not have any moving parts.
The remerging can be performed by the configuration of the flow path, and any known method can be applied. With this motionless mixer 4, the pumps 5, 6
Oil and water supplied from the fuel tank are mixed to form a uniform water-in-oil emulsion fuel. The water-in-oil emulsion fuel adjusted by the motionless mixer 4 passes through the supply path 13 and is heated by the heater 11 as required, after which it is stirred by the next motionless mixer 12 to be used in a boiler or the like. It is designed to reach a spray burner 3 provided in the combustion chamber.

On the other hand, the pulverized coal and oil mixing device 2 includes an agitator 15
Screw feeder 16 for mixing tank 14 with
The pulverized coal C is supplied by the pump 17, and the oil O' is supplied by the pump 17. In this mixing tank 14, pulverized coal C and oil are mixed at a certain ratio.
A mixture with O' is being prepared.
The mixture of pulverized coal and oil prepared in the mixing tank 14 is injected and mixed into the water-in-oil emulsion fuel supply path 13 by the pump 18 . Reference numeral 19 denotes a flow meter, and the flow rate signal from the flow meter 19 is used to control the amount of the mixture supplied by the pump 18 via the control panel 10 so that it has a constant mixing ratio with respect to the emulsion fuel. The injection position of the mixture into the water-in-oil emulsion fuel is spray burner 3.
After being injected, the water-in-oil emulsion fuel is mixed to be uniformly dispersed in the water-in-oil emulsion fuel by a motionless mixer 12, and then combusted while being atomized by a spray burner 3.

The control panel 10 automatically controls the mixing ratio of oil O and water W via the flowmeters 8 and 9, and the mixing ratio of the mixture of pulverized coal C and oil O' and emulsion fuel via the flowmeter 19. However, the mixing ratio of water in the water-in-oil emulsion fuel is preferably 2 to 40 wt%, and the mixing ratio of pulverized coal in the water-in-oil emulsion fuel is preferably 2 to 45 wt%. Further, the mixing ratio of pulverized coal in the mixture injected into the emulsion fuel is 5 to 90 vol%, more preferably 30 to 90 wt%, and even more preferably
It is preferable to set it as 50-90wt%. The oils O and O' may be of the same type, but it is preferable that the oil O' has a higher viscosity than the oil O.

As described above, the fuel made of pulverized coal, water, and oil obtained before the spray burner 3 has pulverized coal dispersed very uniformly. This is because pulverized coal C is mixed with oil O' and is injected into the water-in-oil emulsion fuel while particles are kept separated from each other by the oil, so there is no agglomeration. Extremely good dispersion is achieved, and since the mixture is mixed before the spray burner 3, the spray is immediately sprayed from the spray burner 3 in a uniformly dispersed state, without settling through a long flow path. Moreover, since the mixture containing pulverized coal is only added before the spray burner 3, it is possible to prevent the pulverized coal from wearing out and damaging various devices such as the water-in-oil emulsion fuel adjustment device 1. will be done.

FIG. 2 shows a schematic diagram of an apparatus according to another embodiment for carrying out the method of the invention.

In this embodiment, in addition to the water-in-oil type emulsion fuel adjustment device 1 in the device shown in FIG.
2 are connected in series in this order to form a closed circuit. In this circulation line, the water-in-oil emulsion supplied to the mixing tank 20 via the motionless mixer 4 is circulated by the pump 21, and the water droplets in the oil are finely dispersed each time it repeatedly passes through the motionless mixer 22. This distributed state is maintained. When circulating emulsion fuel in this way, valve 2 in the circulation line
3 is open, and the valve 24 on the flow path 13 side is closed. When the predetermined circulation is completed, the valve 23 is closed or left open.
The valve 24 may be opened to supply the adjusted water-in-oil emulsion fuel to the spray burner 3 through the flow path 13. Injecting and mixing the mixture of pulverized coal C and oil O' into the channel 13 in front of the spray burner 3 is the same as in the previous embodiment.

The valves 23 and 24 are operated by adjusting their respective openings to appropriate degrees, and while the emulsion fuel is being circulated through the circulation line, a portion of the valves 23 and 24 is continuously fed into the flow path 13.
Alternatively, the liquid may be discharged to. 25 is a level meter, which is connected to the control panel 10, and which is connected to the mixing tank 20.
When the emulsion fuel reaches the upper limit U, the pumps 5 and 6 are stopped, and when it reaches the lower limit L, the pumps 5 and 6 are started, so that the emulsion fuel can be stopped and supplied automatically.

FIG. 3 shows a schematic diagram of a further embodiment of an apparatus for carrying out the method of the invention.

In this embodiment, in the apparatus of the embodiment of FIG. The system is equipped with a circulation line driven by. A mixture of pulverized coal and oil is injected into the emulsion fuel in this circulation line, and is uniformly dispersed while being circulated through the circulation line together with the emulsion fuel. At this time, the flow rate Q circulating through this circulation line is set to be sufficiently larger than the flow rate q discharged to the spray burner 3 side. With the circulation line set such that the flow rate Q>q, the water droplets in the emulsion fuel are more finely dispersed, and the pulverized coal is evenly dispersed.

Even in the case of the embodiments shown in FIGS. 2 and 3 described above, since the mixture of pulverized coal and oil is injected and mixed before the spray burner 3, the pulverized coal is uniformly dispersed and sedimentation does not occur. It can be sprayed from a spray burner in a uniformly dispersed state within a short period of time. Furthermore, damage to various devices such as the emulsion fuel adjusting device due to wear caused by the pulverized coal is also suppressed.

As described above, the method of spraying a fuel consisting of pulverized coal, water, and oil according to the present invention involves injecting a mixture of pulverized coal and oil into a water-in-oil type emulsion fuel at a position immediately before a spray burner, and Since the fuel consisting of pulverized coal, water and oil is uniformly mixed and dispersed by a motionless mixer and then immediately sprayed from a spray burner in the uniformly mixed and dispersed state, the emulsion fuel adjustment device is not damaged by the pulverized coal. It is suppressed.
Moreover, since the pulverized coal is mixed with oil and injected into the emulsion fuel, the dispersion is much smoother than when pulverized coal is injected alone. Since the pulverized coal reaches the spray burner, it is possible to spray the pulverized coal in a uniformly dispersed state without causing sedimentation.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of an apparatus for carrying out the method of the invention, FIG. 2 is a schematic diagram of an apparatus according to another embodiment of the invention, and FIG. 3 is a schematic diagram of an apparatus according to a further embodiment of the invention. It is. 1... Adjustment device for water-in-oil emulsion fuel, 2... Mixing device for pulverized coal and oil, 3... Spray burner, 4, 12... Motionless mixer, 5,
6, 18... pump, 8, 9, 19... flow meter,
10... Control panel, 14... Mixing tank, O, O'...
Oil, W...water, C...pulverized coal.

Claims (1)

[Claims] 1. After preparing a water-in-oil emulsion fuel, when spraying the emulsion fuel from a spray burner, injecting a mixture of pulverized coal and oil into the emulsion fuel at a position immediately in front of the spray burner, and The fuel consisting of pulverized coal, water and oil is uniformly mixed and dispersed by a motionless mixer and then immediately sprayed from a spray burner in the uniformly mixed and dispersed state. Spraying method.