JP2006329438A - Emulsion fuel manufacturing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To continuously and stably supply emulsion fuel in which fine droplets are uniformly dispersed, to a combustion device without impairing its quality. <P>SOLUTION: In a static mixer 14, fuel oil, an emulsion agent and water are divided and primarily mixed to prepare the emulsion fuel, and the emulsion fuel is delivered from the static mixer 14 to a magnetic cascade pump 15, and secondarily mixed by shearing. Here, a part of the emulsion fuel is returned to an upstream side of the pump 15 from a return pipe 16 connecting the upstream and downstream of the pump 15, and the secondary mixing in the pump is urged by adjusting the flow of emulsion fuel flowing in the pump 15, thus the emulsion fuel in which fine droplets are uniformly dispersed is manufactured, and delivered to the combustion device 21. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an apparatus for producing emulsion fuel by mixing water and an emulsifier with fuel oil and supplying the emulsion fuel to a combustion apparatus such as a boiler. The fuel oil, water and the emulsifier are combined into an apparatus combining a mixer and a pump. The present invention relates to a means for continuously and stably producing an emulsion fuel in which fine droplets having a diameter of 20 μm or less are uniformly dispersed in fuel oil.

It is widely performed to add water and an emulsifier to fuel oil, and spray and burn emulsion fuel in which water droplets are dispersed in fuel oil in a furnace of a combustion apparatus. A large number of fine water droplets are present in the sprayed emulsion fuel droplets, and these water droplets are rapidly heated in the furnace and explode (micro explosion), whereby the emulsion fuel droplets are atomized. This micro explosion improves combustion efficiency and suppresses the generation of NOx and soot. In order to burn the emulsion fuel and obtain good combustion characteristics, it is important to uniformly disperse fine water droplets in the fuel oil. In JP-A-5-157221 and JP-A-10-185183, fuel oil and water are supplied to one mixer without using an emulsifier and mixed, and the obtained emulsion fuel is immediately burned using a pump. There is a description of the method of supplying to the device.
JP-A-5-157221 JP-A-10-185183

  However, conventionally, fuel oil and water are mixed in one mixer, so it is difficult to produce an emulsion fuel in which fine water is uniformly dispersed in the fuel oil, even if fine water droplets are evenly dispersed. Even if the obtained emulsion fuel is obtained, since the emulsifier is not used, the water droplets are aggregated and the dispersion of the water droplet diameters becomes non-uniform. Black smoke is generated.

  The present invention supplies a predetermined amount of fuel oil, water and an emulsifier, performs primary mixing with a static mixer, and further performs secondary mixing with a magnet cascade pump that supplies emulsion fuel to a combustion device, thereby providing fine water droplets. It is an object of the present invention to provide an emulsion fuel production apparatus that can continuously and stably supply an emulsion fuel in which oil is uniformly dispersed to a combustion apparatus without degrading its quality.

  In order to achieve the above object, the present invention provides a static mixer for mixing water, fuel oil, and an emulsifier, and a magnet cascade pump for further supplying a dispersion (emulsion fuel) to a combustion device by further mixing the mixture from the static mixer. And a feedback unit for refluxing a part of the dispersion from the downstream side to the upstream side of the magnet cascade pump.

  According to the present invention, water, fuel oil, and emulsifier are firstly mixed by a static mixer, and the mixed solution that is primarily mixed by a static mixer is sent to a magnetic cascade pump and further mixed by a second, and a fine particle having a diameter of 20 μm or less. Emulsion fuel is produced continuously and stably in which water droplets are uniformly dispersed (emulsion fuel) and the amount of water contained in the emulsion fuel is adjusted to a maximum volume ratio of 6: 4 by the volume ratio of fuel oil to water. Thus, it is possible to supply the fuel device, and there is an effect that reduction of fuel consumption and reduction of NOx and soot emission can be realized.

  Embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows an emulsion fuel production apparatus. In the practice of the present invention, Concor-S (trade name) was used as the emulsifier, and A heavy oil was used as the fuel.

The emulsifier stored in the emulsifier tank 1 is supplied to the fuel supply pipe 12 through the emulsifier supply pipe 2, the volumetric pump 3, and the check valve 4. By controlling the rotational speed of the pump 3 by the inverter 5, a predetermined amount of emulsifier is sent. The supply amount of the emulsifier is 1: 250 to 1: 500 in volume ratio with the fuel.

The water stored in the water tank 6 is supplied to the fuel supply pipe 12 through the water supply pipe 7, the volume measuring pump 8 and the check valve 9. By controlling the rotational speed of the pump 8 by the inverter 10, a predetermined amount of water is sent. The supplied water can be adjusted from 10: 0 to 6: 4 in volume ratio with the fuel.

The fuel oil stored in the fuel oil tank 11 is combined with water through the fuel supply pipe 12 and the check valve 13 and then sent to the static mixer 14.

In the static mixer 14, as shown in FIG. 2, a large number of elements 26 are installed in the circular pipe 25, and fuel oil, emulsifier, and water are divided and primarily mixed every time they pass through the elements. Thus, an emulsion fuel is obtained. The emulsion fuel flowing out from the static mixer is sent to the magnet cascade pump 15.

In the pump 15, as shown in FIG. 3, the outer magnet 28 is rotated by the motor 27, and the inner magnet 29 and the shaft 31 are rotated along with the rotation. The impeller 30 is rotated by the rotation of the shaft 31, the emulsion fuel is sucked into the casing 32 by the rotation of the impeller 30, and the emulsion fuel is sheared in the gap between the impeller 31 and the casing 32, so that the emulsion fuel is subjected to secondary mixing. Is done. The secondary mixed emulsion fuel is discharged from the pump 15.

A part of the emulsion fuel discharged from the pump 15 is returned to the upstream side of the pump 15 by providing a return pipe 16 that connects the upstream and downstream sides of the pump 15. By adjusting the opening of the needle valve 17 provided in the middle of the return pipe 16 to maintain the rotation speed of the pump 15 at about 3000 rotations and adjusting the flow rate of the emulsion fuel flowing through the pump 15, secondary mixing in the pump is performed. Prompt and produce emulsion fuel with fine water droplets uniformly dispersed.

The emulsion fuel passes through a pressure gauge 18, a flow meter 19, and a needle valve 20 provided downstream of the pump 15, and is sent to the combustion device 21. The flow rate of the emulsion fuel is adjusted by the flow rate control device 22 and the inverter 23 so that the flow rate in the flow meter 19 becomes a predetermined amount. By adjusting the opening degree of the needle valve 19, the discharge pressure of the emulsion fuel sent to the combustion device 20 can be kept constant.

In the present embodiment, emulsion fuel in which fine water droplets having a diameter of 10 to 20 μm are uniformly dispersed by performing primary mixing with a static mixer and further providing return piping to the magnet cascade pump and performing secondary mixing in the pump. Can be easily produced. The supply amounts of water and emulsifier are also adjusted by controlling the rotation speed of the water and emulsifier pump via an inverter.

Further, a signal indicating the operation state of the combustion device is input to the control device 24, and the number of rotations of the water and emulsifier pumps is controlled to set the water and emulsifier flow rates, so that they are included in the emulsion according to the operation state. The amount of moisture that can be changed can be changed. For example, at the start of the combustion device, ignitability is improved by sending only fuel to the combustion device, and after reaching a state where the combustion device is operating to a certain extent, water and an emulsifier are supplied to burn the emulsion fuel Let

In the above embodiment, water and A heavy oil are mixed, but instead of water, wastewater that has been subjected to water purification treatment of waste liquid in various industrial processes, lubricating oil for machinery and equipment, automotive engine oil, food oil instead of A heavy oil It is possible to use waste oil having a kinematic viscosity at 50 ° C. in the range of 20 cst or less.

A combustion test was conducted by applying the emulsion fuel production apparatus of the present invention to a horizontal cylindrical combustion furnace (diameter: Φ300 mm, length: 1,000 mm). In this combustion furnace, emulsion fuel is sprayed by a six-hole two-fluid nozzle, and combustion air is supplied into the combustion furnace through a swirler around the nozzle. The supply amount of the emulsion fuel was 0.15 L / min, and A heavy oil was used as the fuel. The amount of water contained in the emulsion fuel was changed by 0, 10, 20, and 30%, and the combustion furnace exhaust gas temperature and gas composition at each water amount were measured. Concor-S was used as the emulsifier, and the ratio of the emulsifier to the fuel was 1: 350.

When emulsion fuel is combusted, the concentration of NOx, SO2 and CO is lower than when A fuel oil is combusted, and the concentration of these gas components further decreases as the amount of water contained in the emulsion fuel increases. Obtained. On the other hand, the exhaust gas temperature decreased from 951 ° C. to 840 ° C. as the water content increased. This is because the amount of heavy fuel oil A contained per unit mass of the emulsion fuel decreases with the increase in the amount of water, and the calorific value of the emulsion fuel decreases. However, since the CO concentration is lower when the water content is increased, the combustion characteristics are improved by the micro-explosion of the emulsion fuel as the water content increases in the range up to 30%. I understand that. Accordingly, since the NOx and SO2 concentrations also decrease with the increase in the amount of water, the use of emulsion fuel enables low NOx and low SOx combustion, indicating the effectiveness of the emulsion fuel production apparatus of the present invention.

Table Measurement results of exhaust gas temperature and gas analysis Fuel A heavy oil emulsion Emulsion Emulsion
(10% water) (20% water) (30% water)
Exhaust gas temperature [° C] 951.0 884.5 852.0 829.5
NOx [ppm] 115 99 88 71
CO [ppm] 25 6 3 0
CO2 [%] 12.06 11.93 11.64 10.47
O2 [%] 497 5.15 5.52 7.08
SO2 [ppm] 126 103 98 87

The conceptual diagram which shows one Embodiment, when the emulsion fuel manufacturing apparatus which concerns on this invention is applied to a combustion apparatus The schematic diagram showing the form with which primary mixing is performed in the emulsion fuel manufacturing apparatus of this invention Schematic of a magnet cascade pump in which secondary mixing is performed in the emulsion fuel production apparatus of the present invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Emulsifier tank 2 ... Emulsifier supply piping 3 ... Volume measuring pump 4 ... Check valve 5 ... Inverter device 6 ... Water tank 7 ... Water supply piping 8 ... Volume measuring pump 9 ... Check valve 10 ... Inverter device 11 ... Fuel oil tank 12 ... Fuel supply pipe 13 ... Check valve 14 ... Static mixer 15 ... Magnet cascade pump 16 ... Return pipe 17 ... Needle valve 18 ... Pressure gauge 19 ... Flow meter 20 ... Needle valve 21 ... Combustion device 22 ... Flow control Device 23 ... Inverter 24 ... Control device 25 ... Element 26 ... Circular tube 27 ... Motor 28 ... Outer magnet 29 ... Inner magnet 30 ... Shaft 31 ... Impeller 32 ... Casing

Claims (1)

A static mixer that mixes water, fuel oil, and emulsifier, a magnetic cascade pump that further mixes the liquid mixture from the static mixer and supplies the dispersion (emulsion fuel) to the combustion device, and a downstream side to an upstream side of the magnetic cascade pump An emulsion fuel production apparatus comprising a feedback unit for refluxing a part of the dispersion liquid.