JPH09243052A - Method of burning highly viscous heavy oil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce nitrogen oxides produced at combustion of highly viscous heavy oil, by supplying the emulsifying oil of highly viscous heavy oil at high temperature and high pressure obtained by adding water into fuel in an emulsifier, to a high-pressure air current type of burner while keeping the emulsified condition, and atomizing it for combustion. SOLUTION: A specified quantity of water sent from a water pour line 1 to a water pour line 1' by a lubricating water pump 2 is heated to a specified temperature by a poured water heater 3, and flows into an emulsifier 4. On the other hand, the highly viscous heavy oil which has flowed out from a highly viscous heavy oil tank 9 to a highly viscous heavy oil supply line 8' with a highly viscous heavy oil supply pump 10 flows into an emulsifier 4 via a highly viscous oil heater 11. Then, water and the highly viscous heavy oil are mixed and emulsified in an emulsifier 4, and is sent to a high-pressure air current type of burner 7 via a pressure adjusting valve 6. In this case, the temperature of the water at emulsification is made 100 deg.C, and the highly viscous heavy oil whose viscosity at 50 deg.C is 400cSt or over is emulsified, and it is burned, keeping the stable condition.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combustion method for burning high-viscosity heavy oil for power generation or steam generation.

[0002]

2. Description of the Related Art Conventionally, high-viscosity heavy oil has been used as a fuel, heated to improve fluidity, and burned by using a high-pressure airflow burner to remove nitrogen oxides and soot dust generated in the combustion gas. It is widely practiced to remove them and obtain heat and power with a removal device provided for this purpose. According to this combustion method, heat and power can usually be obtained at a lower cost than using general heavy oil as a fuel.

However, when burning high-viscosity heavy oil,
Nitrogen and high carbon content in high-viscosity heavy oil are higher than general heavy oil, so a large amount of nitrogen oxides and soot are generated, and when trying to obtain the same amount of heat and power as general heavy oil, nitrogen in combustion gas Nitrogen oxides and dusts will be generated that exceed the throughput of the removal device that removes oxides and dusts.

Nitrogen oxides and soot that are not treated by the removing device are released into the atmosphere and pollute the atmosphere, so that the high-viscosity heavy oil has the disadvantage that it cannot be used as practically as general heavy oil.

[0005]

SUMMARY OF THE INVENTION In order to reduce the nitrogen oxides and soot dust generated during the combustion of such high-viscosity heavy oil, the present invention adds water to the fuel to obtain a high-viscosity, high-viscosity high viscosity. An object of the present invention is to provide a combustion method in which an emulsified oil of heavy oil is supplied to a high-pressure airflow type burner while maintaining an emulsified state, atomized and burned.

[0006]

In order to solve the above problems, a method for burning high-viscosity heavy oil according to the present invention comprises an oil supply means for supplying high-viscosity heavy oil, a heating means for the high-viscosity heavy oil, and water. And a water heater for supplying water, a high-viscosity heavy oil supplied from the oil supply means via the heating means, and water supplied from the water supply means via the heater. Using a system having an emulsifier for emulsification and a high-pressure airflow burner, operating at 100 ° C. or higher, emulsifying a high-viscosity heavy oil having a viscosity of 400 cSt or higher at 50 ° C. and burning it while maintaining a stable state. Characterize.

The high-viscosity heavy oil used in the present invention has a viscosity at 50 ° C. of 400 cSt or more. The upper limit of the viscosity is not particularly limited. These high-viscosity heavy oils are heated to have a kinematic viscosity suitable for burner combustion of about 25 cSt. The heating temperature varies depending on the type of high-viscosity heavy oil, but is about 100 ° C. in the case of high-viscosity heavy oil having a viscosity of 400 cSt at 50 ° C.

In the present invention, the above-mentioned high-viscosity heavy oil is mixed with water in an emulsifier, emulsified, and then sent to a burner and burned. The mixing is performed at a temperature at which the high-viscosity heavy oil has sufficient fluidity, for example, a temperature at which the above-mentioned high-viscosity heavy oil has a kinematic viscosity of 25 cSt. The water mixed with the high-viscosity heavy oil is heated by a heater in advance. This is because at the time of emulsification, the temperature and thus the fluidity of the high-viscosity heavy oil are not lowered. The temperature of water at the time of emulsification is 100 ° C. or higher, and preferably the temperature of high viscosity heavy oil at the time of mixing or higher. The lower one is allowable within -20 ° C as compared with the temperature of the high-viscosity heavy oil during emulsification. Since emulsified oil has a temperature above the boiling point of water at atmospheric pressure, holding pressure is required. That is, it is necessary to maintain the pressure in the system above a pressure at which water does not vaporize (heated high-viscosity heavy oil or saturated water vapor pressure at a higher temperature of water). This is because, for example, when the pressure in the system between the emulsifier and the burner becomes equal to or lower than the saturated steam pressure, the water is bumped to destroy the emulsified state and the supply of fuel to the burner is interrupted, so to prevent it. Is. Therefore, the high-viscosity heavy oil heater, the water heater, the emulsifier, and the pipes connected to these must be able to withstand the temperature and pressure determined by the high-viscosity heavy oil used as described above.

The emulsifier used in the present invention is for obtaining water-in-oil type emulsified oil of water and highly viscous heavy oil, which is optimum for combustion.

The high-pressure air flow type burner can be used without particular limitation as long as it is a burner that can atomize the emulsified high-viscosity heavy oil to a particle size necessary for combustion without changing the emulsified state.

The pressure control valve can be set to any pressure so that the pressure of the emulsified oil of the high-viscosity heavy oil can be maintained above the saturated vapor pressure at the temperature of the water droplet in the oil under any operating condition of the combustion apparatus. It is provided in order to prevent the emulsified state from being destroyed by boiling of water-in-oil drops due to the pressure drop of the emulsified oil. The pressure of the emulsified oil is preferably 5 atm or higher.

According to the present invention, a high-viscosity heavy oil and heated water are supplied to the emulsifier, and the produced emulsified oil is held by a check valve to be supplied to a high-pressure air stream type burner, which is a series of operations until atomization. I do.

[0013]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a system diagram of a combustion apparatus for high-viscosity heavy oil which can be used in the present invention.

A predetermined amount of water sent from the water injection line 1 to the water injection line 1'by the water injection pump 2 is heated to a predetermined temperature by the water injection heater 3 and flows into the emulsifier 4. On the other hand, the high-viscosity heavy oil that has flowed out from the high-viscosity heavy oil tank 9 to the high-viscosity heavy oil supply line 8 ′ by the high-viscosity heavy oil supply pump 10 flows into the emulsifier 4 via the high-viscosity heavy oil heater 11. Then, the water and the high-viscosity heavy oil are mixed and emulsified in the emulsifier 4, and the high-pressure airflow burner 7 is passed through the pressure control valve 6.
Sent to The amount of high-viscosity heavy oil supplied is adjusted to a predetermined amount by the oil amount adjustment valve 5. The pressure control valve 6 is
It has a built-in pressure gauge and adjusts the passage amount of emulsified oil so that the pressure on the emulsifier side becomes a predetermined value (for example, 5 atm or more).
Further, even when the pressure at the burner source is lowered for extinguishing the fire, it also has an effect of preventing the emulsified oil whose emulsified state is destroyed from being supplied to the burner.

[0016]

EXAMPLES The present invention will be specifically described below with reference to Examples, Comparative Examples and Test Examples. Example Using the combustion apparatus shown in FIG. 1, high viscosity heavy oil A having the properties shown in Table 2 was burned, and the concentrations of nitrogen oxides and dust in the combustion gas were measured. The temperatures of the high-viscosity heavy oil A and water were adjusted to 130 ° C ± 2 ° C at the inlet of the emulsifier. The concentration of nitrogen oxides in the combustion gas was measured according to JIS B7982, and the concentration of soot and dust in the combustion gas was measured according to JIS Z8808. Table 1 shows the measurement results.

[0017]

[Table 1]

Comparative Examples 1 to 3 In the apparatus shown in FIG. 1, each heavy oil in Table 2 is heated to a temperature at which the kinematic viscosity (25 cSt) suitable for burner combustion in Table 2 is reached.
It was sent directly to the burner 7 through the bypass line 13 and burned without passing through the emulsifier 4. At that time, the concentrations of nitrogen oxides and soot in the combustion gas were measured by the same method as in the example. Table 1 shows the measurement results.

[0019]

[Table 2]

As is clear from the results of Tables 1 and 2,
According to the method of the present invention, the high-viscosity heavy oil A could be burned with the same amount of nitrogen oxides and dust as in the case of burning general heavy oil by the usual method without using an emulsifier.

[0021]

Scope of application of the invention The present invention is not limited to the above-described embodiments, but can be modified in various ways. For example, as shown by the broken line in FIG. 1, a thermometer or a temperature sensor is provided in the emulsifier, and the controller 14 automatically controls the heater of the injected water based on the measured value of the temperature measured here. However, the temperature may be maintained at a predetermined temperature.
In addition, a pressure gauge or pressure sensor is provided in the emulsifier, and the controller 14 automatically controls the pressure control valve or the water injection pump and the high-viscosity heavy oil supply pump based on the measurement value of the pressure gauge or sensor to obtain the required pressure. May be configured to be retained.

Further, if necessary, a device for controlling the flow rate and temperature of high-viscosity heavy oil and water supplied to the emulsifying device and a device for controlling the viscosity of the emulsified oil may be provided.

Instead of the pressure control valve, a check valve for stopping the supply of the emulsified oil to the burner when the pressure on the emulsifier side is below a predetermined value may be used. Furthermore, a safety device may be provided that automatically stops the heating of water when the pressure of the emulsified oil reaches a pressure at which its stability is not maintained.

[0024]

As described above, according to the present invention, when burning high-viscosity heavy oil, generation of nitrogen oxides and soot dust can be suppressed to about the same level as when burning general heavy oil.

[Brief description of drawings]

FIG. 1 is a system diagram showing a combustion device for high-viscosity heavy oil according to an embodiment of the present invention.

[Explanation of symbols]

(1, 1 ', 1 "): Water injection line, 2: Water injection pump,
3: Water injection heater, 4: Emulsifier, 5: Oil amount control valve, 6: Pressure control valve, 7: High pressure air flow type burner, (8, 8 ',
8 "): high viscosity heavy oil supply line, 9: high viscosity heavy oil tank, 10: high viscosity heavy oil supply pump, 11: high viscosity heavy oil heater, (12, 12 '): high viscosity heavy oil return line, 1
3: Emulsifier bypass line, 14: Controller.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Jun Uehara 8th Chidori-cho, Naka-ku, Yokohama, Kanagawa Japan Central Research Institute

Claims (1)

[Claims] 1. An oil supply means for supplying high-viscosity heavy oil, a heating means for the high-viscosity heavy oil, a water supply means for supplying water, the water heater, and the heating means to the heating means. Operating at 100 ° C. or higher using a system having an emulsifier for mixing and emulsifying high-viscosity heavy oil supplied through the heater and water supplied from the water supply unit through the heater, and a high-pressure airflow burner And the viscosity at 50 ° C is 400c
A method of burning high-viscosity heavy oil, which comprises emulsifying high-viscosity heavy oil of St or higher and burning it while maintaining a stable state.