JP2010175193A - Utilization method for liquid containing low concentration combustive organic substance, and combustion system using the liquid fuel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide highly safe utilization of liquid containing a low concentration combustive organic substance preventing blocking of a passage due to condensation of an atomized body of a high concentration combustive organic substance, and capable of avoiding danger of backfire or explosion. <P>SOLUTION: An ultrasonic atomizing device 1 is provided, atomizing the low concentration combustive organic substance, a blow fan F is provided, supplying the obtained atomized body as a fuel of a combustor 2 using carrier gas and supplying the exhaust gas from the combustor 2 as a carrier gas to the ultrasonic atomizing device 1, and an oxygen measurement part S2 is provided, measuring the oxygen concentration in the exhaust gas. It is characterized by that it has a control part 3 carrying out the control of stopping ultrasonic waves or the control of an ultrasonic vibration force of the ultrasonic atomizing device 1, or/and stopping of supply or the control of a supply amount of the carrier gas when a measured value of the oxygen measurement part S2 exceeds a predetermined value. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for using a liquid containing a low-concentration combustible organic substance and a combustion system using the liquid fuel. For example, the high-concentration alcohol obtained by atomizing a low-concentration alcohol solution with an ultrasonic atomizer It is related with the combustion system which uses the atomized body of this for the fuel of a combustion apparatus.

  Conventionally, a technique for atomizing and burning liquid fuel by ultrasonic vibration is known. When the liquid fuel is atomized in this way, an improvement in ignitability is expected, and it is considered that the control of the combustion amount becomes easier. Specifically, as illustrated in FIG. 3, an ultrasonic vibrator 113 is installed at the bottom of the fuel storage portion 117 of the apparatus main body A, and the liquid fuel is jetted from the fuel liquid level while being atomized by ultrasonic vibration. Further, an air supply chamber 118 and a fuel atomization chamber 119 are formed by a space portion on the liquid level, and an air guide plate 122 is provided to send combustion air along the liquid level to the fuel atomization chamber 119. An improved liquid fuel combustion apparatus has been proposed (see, for example, Patent Document 1). Here, by arranging the check valve 141 in the path from the spray outlet 121 to the combustion cylinder 132, it is possible to prevent odor and backfire during fire extinguishing.

  Further, a liquid fuel vaporization combustion apparatus having a configuration in which a mist fuel generated by an ultrasonic generator is supplied to a preheating burner for preheating a carburetor of a main burner and the mist fuel is combusted by the preheating burner head. It has been proposed (see, for example, Patent Document 2). These are methods in which liquid fuel is directly atomized by ultrasonic vibration. Liquid fuel has a high concentration of combustible substances, and can be easily ignited and burned by using any ignition means.

Japanese Patent Laid-Open No. 10-38220 JP-A-10-246408

However, the following problems may occur in the combustion apparatus using the atomized liquid fuel as described above.
(I) There is a problem that the atomized fuel is condensed and stays in the piping during the transfer from the ultrasonic atomizer to the combustion apparatus, and the atomized fuel cannot be sufficiently transferred. Further, such condensed atomized fuel may generate abnormal heat or ignite due to reaction with the carrier air.
(Ii) When the generated atomized fuel is conveyed by combustion air and burned by a combustion device (for example, a burner), there is a risk of backfire from the conveyance channel. In the configuration as shown in FIG. 3, a device provided with the check valve 141 is disclosed. However, a specific backfire prevention function is not clear, and in reality, a device having such a check valve 141 is used. Not put into practical use. For example, a method of disposing a backfire prevention material having pores such as sintered metal in the flow path is possible, but it may cause condensation of the atomized fuel and is not suitable for such a combustion apparatus.
(Iii) When it cannot be transported with combustion air for safety, the transport gas is limited to an inert gas (N ₂ or the like) that does not contain oxygen (O ₂ ), and a separate transport gas is prepared. Equivalent supply facilities are required.

  Therefore, the present invention has been made in view of the current state of the prior art, and atomized a solution containing a combustible organic substance by an ultrasonic atomizer, and atomization of the obtained high-concentration combustible organic substance When the body is supplied as fuel to the combustion apparatus, the blockage of the flow path due to condensation of the atomized body in the middle of the supply flow path is prevented, and the atomized body of the high-concentration combustible organic substance is conveyed by air An object of the present invention is to provide a method of using a liquid containing a low-concentration combustible organic substance that can avoid the risk of flashback or explosion. It is another object of the present invention to provide a combustion system with high energy efficiency by using a liquid containing a low concentration of combustible organic substance as a fuel for the combustion apparatus and effectively using the exhaust gas of the combustion apparatus.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have achieved the above object by the following method for using a liquid containing a low-concentration combustible organic substance and a combustion system using the liquid fuel. The present inventors have found that the present invention can be accomplished and have completed the present invention.

The present invention atomizes a low-concentration combustible organic substance-containing liquid using an ultrasonic atomizer, and uses a carrier gas for the high-concentration combustible organic-substance atomized body obtained by the atomization. In the method for using the liquid, which is supplied as a fuel for the combustion apparatus and disposes of the treated liquid after the atomization as an discharged liquid,
The exhaust gas from the combustion device is used as the carrier gas, the oxygen concentration in the exhaust gas is measured, and when the measured value exceeds a predetermined value, the ultrasonic atomization device is stopped or Control of the sonic vibration force or / and the supply gas supply stop and supply amount control are performed.

The present invention also includes an ultrasonic atomizer that atomizes a liquid containing a low-concentration combustible organic substance. The atomized body containing a high-concentration combustible organic substance obtained by the atomization is used as a carrier gas. A combustion system for use as a fuel for a combustion device,
A carrier gas passage connecting the exhaust gas discharge section of the combustion device and the ultrasonic atomizer, and exhaust gas from the combustion device is supplied to the ultrasonic atomizer as the carrier gas via the carrier gas passage. A conveying means and an oxygen measuring unit for measuring the oxygen concentration in the exhaust gas are provided, and when the measured value of the oxygen measuring unit exceeds a predetermined value, the ultrasonic atomization of the ultrasonic atomizer is stopped or It has a control part which controls vibration force or / and the supply stop of the above-mentioned carrier gas, and control of the supply amount.

  In combustion systems that use atomized fuel containing low-concentration combustible organic substances, it is important to prevent condensation of the atomized body in the transport channel and prevent backfire from the fuel device or transport channel. . In the present invention, the oxygen concentration in the exhaust gas of the combustion apparatus is usually 3 to 5%, the gas temperature is 200 to several hundred degrees Celsius, and is maintained at about 80 to 100 degrees Celsius exceeding the condensation temperature of the organic substance. Therefore, the exhaust gas was effectively utilized as a carrier gas for the atomized body. That is, the vaporization of the combustible organic substance using the latent heat of the exhaust gas can be promoted and condensation in the flow path can be suppressed, and the risk of backfire can be avoided as a low oxygen-containing gas. Further, as a safety net, by measuring the oxygen concentration in the exhaust gas and controlling the supply amount or supply stop of the atomized body, a method for using a highly safe and low-concentration combustible organic substance-containing liquid and the method It has become possible to provide a combustion system using liquid fuel. Furthermore, by using the energy of the low-concentration combustible organic substance-containing liquid as well as effectively using the heat quantity of the exhaust gas, it has become possible to ensure high energy efficiency as a whole system.

  Here, the “low concentration” is a concentration in a range where the liquid containing combustible organic matter does not spontaneously ignite or ignite / combust by the ignition means at room temperature (for example, average temperature 6 to 28 ° C.). However, if the combustible organic substance is an alcohol, for example, it is 20% or less. “High concentration” means the concentration of a combustible organic substance-containing atomized body in a range that can be ignited and combusted by an ignition means at room temperature, and differs depending on the combustible organic substance. If there is, it is 60% or more.

  The present invention is a method of using a liquid containing a low-concentration combustible organic substance, wherein the flame in the fuel supply passage from the ultrasonic atomizer to the combustion device is monitored and a flame is detected. The fuel supply flow path is blocked.

  Further, the present invention is a combustion system using the liquid fuel containing the low-concentration combustible organic substance, wherein the fuel is supplied to the fuel supply channel for supplying the atomized body from the ultrasonic atomizer to the combustion device. A flame detector for monitoring the occurrence of a flame in the supply flow path or the escape of the flame, and an on-off valve for shutting off the fuel supply flow path are provided. When the flame detection section detects a flame, the control section The fuel supply flow path is shut off by braking the on-off valve.

  In the above configuration, while utilizing the latent heat of the exhaust gas and the characteristics as a low oxygen content gas, the safety on the supply side to the ultrasonic atomizer by controlling the supply of the atomized body by monitoring the oxygen concentration in the exhaust gas A net is provided. The present invention further detects the flame in the fuel supply flow path from the combustion apparatus to the ultrasonic atomizer, and performs control to block backfire in the flow path, thereby providing the ultrasonic atomizer. The side safety net is configured. As a result, a safety mechanism can be configured for both the supply side and the supply side of the ultrasonic atomizer that stores a predetermined amount of liquid fuel, and a higher level of safety is ensured.

  The present invention is a method for using a liquid containing a low-concentration combustible organic substance, wherein a second fuel and combustion air are supplied to the combustion device, and a combustion amount necessary for the combustion device is ensured. In addition, in a state where the flow rate and temperature of the exhaust gas conveyed to the ultrasonic atomizer are stable, ultrasonic waves of the ultrasonic atomizer are supplied, and an ultrasonic vibration force is applied according to the combustion amount of the combustion device. Or / and the exhaust gas flow rate conveyed to the ultrasonic atomizer is controlled.

  With the above configuration, it has become possible to effectively use a low-concentration combustible organic substance-containing liquid as a fuel for a combustion apparatus. When the system is started up or when the supply amount of the liquid fuel varies, it is necessary to ensure the combustion amount with the combustion device alone. In order to cope with such a case, the present invention supplies a second fuel and combustion air to the combustion device and operates the ultrasonic atomizer under stable conditions, thereby achieving low-concentration combustion with high safety. It is possible to provide a method of using a liquid containing a conductive organic substance.

  The present invention is a method for using the low-concentration combustible organic substance-containing liquid, and detects the concentration of the combustible organic substance contained in the treatment liquid after being atomized in the ultrasonic atomizer. In the case where the concentration is lower than the predetermined concentration, the liquid is collected as the discharged liquid.

  As described above, for a liquid containing a low-concentration combustible organic substance, the organic substance atomized by ultrasonic waves is used as a fuel. On the other hand, if the organic substance is not sufficiently removed, combustion in the treatment liquid Organic materials are still valuable for use as fuel and may not be emitted as they are. The present invention detects the concentration of combustible organic substances in the treatment liquid, and selects the circulation for recovery and reuse as an exhaust liquid close to the clean liquid, thereby maximizing the liquid containing combustible organic substances. It was possible to use it effectively.

BRIEF DESCRIPTION OF THE DRAWINGS Explanatory drawing which illustrates the whole structure of the fuel provision system for the combustion apparatus which concerns on this invention. Explanatory drawing which illustrates the structure of the ultrasonic atomization apparatus which concerns on this invention. Explanatory drawing which illustrates the structure of the liquid fuel combustion apparatus which concerns on a prior art.

  Embodiments according to the present invention will be described in detail with reference to the drawings. A combustion system according to the present invention (hereinafter sometimes referred to as “the present combustion system”) includes an ultrasonic atomizer that atomizes a liquid containing a low concentration of combustible organic matter (hereinafter sometimes referred to as “liquid fuel”). A high-concentration combustible organic-containing atomized body obtained by the atomization is supplied as a fuel for the combustion apparatus using a carrier gas, and the combustion exhaust gas discharge unit of the combustion apparatus and the ultrasonic atomization apparatus A carrier gas channel connecting the gas, a carrier means for supplying exhaust gas from the combustion device as the carrier gas to the ultrasonic atomizer through the carrier gas channel, and measuring an oxygen concentration in the exhaust gas An oxygen measuring unit, and when the measured value of the oxygen measuring unit exceeds a predetermined value, the ultrasonic atomizing device is stopped and / or the ultrasonic vibration force is controlled or / and the supply of the carrier gas is stopped. And a control unit that controls the supply amount And wherein the Rukoto.

  Specifically, as illustrated in FIG. 1, the combustion system is configured mainly by an ultrasonic atomizer 1, a combustion device 2, and a control unit 3 that controls these functions. Liquid fuel is introduced into the ultrasonic atomizer 1 continuously or batchwise from the liquid fuel introduction part 1 a and is atomized inside the ultrasonic atomizer 1. The atomized atomized body is transported by the transport gas supplied from the transport gas introducing section 1b, and is fed from the atomized body feed section 1c to the fuel supply flow path L1. The atomized body supplied to the combustion apparatus 2 via the fuel supply flow path L1 via the atomized body supply section 2a is combusted inside the combustion apparatus 2, and is discharged as exhaust gas from the exhaust gas discharge section 2b to the exhaust gas flow path L2. To be discharged. A part of the exhaust gas is supplied to the ultrasonic atomizer 1 as a carrier gas via a carrier gas passage L3 provided by branching the exhaust gas passage L2, and the remaining exhaust gas is recovered as waste heat. It is supplied to a device 4 (for example, a boiler), and heat energy is recovered and exhausted. The liquid (drainage) atomized by the ultrasonic atomizer 1 is discharged continuously or batchwise from the liquid discharger 1d to the drainage flow path L4.

  At this time, in order to prevent backfire, the fuel supply flow path L1 is provided with a flame detection unit S1 that monitors the occurrence of a flame or the escape of the flame and an on-off valve V1 that can shut off the fuel supply flow path L1. Yes. The carrier gas flow path L3 has a heat exchanger 5 for preventing overheating due to the exhaust gas temperature, and an air supply fan F (corresponding to “conveying means”) that supplies the exhaust gas as the carrier gas to the ultrasonic atomizer 1. ) And an oxygen measuring unit S2 for measuring the oxygen concentration in the carrier gas (exhaust gas). As will be described later, when the exhaust gas temperature supplied to the ultrasonic atomizer 1 is relatively low (about 80 to 100 ° C.), the heat exchanger 5 is not required. The drainage flow path L4 is provided with a drainage pump P, an organic substance measuring unit S3 for measuring the concentration of the combustible organic substance contained in the treated liquid (drainage), and a switching valve V2. When the substance is below a predetermined concentration, it is recovered as an effluent, and when it is below the predetermined concentration, it is supplied again to the ultrasonic atomizer 1 via the circulation channel L5. The on-off valve V1 and the switching valve V2 are braked (ON-OFF) and the air supply fan F and the drainage pump P are braked (ON-OFF or flow rate control). In addition, the control unit 3 controls the detection signal of the flame detection unit S1 or the concentration signal of the oxygen measurement unit S2 or the organic substance measurement unit S3 as an index.

  Here, “combustible organic substances” are water-soluble hydrocarbon compounds such as alcohols and acetones, and examples thereof include methanol, ethanol, butanol, dimethyl ketone, and methyl ethyl ketone. “Low concentration” is a concentration in a range in which a combustible organic substance-containing liquid does not spontaneously ignite or ignite / combust by an ignition means at room temperature (for example, an average temperature of 6 to 28 ° C.). For example, in the case of alcohols, it is 20% or less. “High concentration” means the concentration of the combustible organic substance-containing atomized body in a range that can be ignited and combusted by the ignition means at room temperature, and varies depending on the combustible organic substance. It is. The ultrasonic atomizer 1 can form an atomized body having a concentration in the range of 60 to 99%, depending on the liquid containing combustible organic substances, the operating conditions, and the like. The “combustion device” is, for example, a burner or the like. The combustion device 2 is provided in, for example, a waste heat recovery facility (for example, a boiler) or a prime mover (for example, a gas engine, a gas turbine, or the like).

One feature of the present combustion system is that the exhaust gas from the combustion device 2 is used as a carrier gas. Air or oxygen can be used separately as the carrier gas,
(I) Transportation by a low oxygen-containing gas for avoiding the risk of ignition or flashback when the atomized or transpirated combustible organic substance is transported to the combustion device 2 under high-concentration oxygen conditions is preferable. Since the oxygen concentration in the exhaust gas of the combustion device 2 is 3 to 5%, this condition is being observed. (Ii) The atomized or evaporated flammable organic material is supplied to the combustion device 2 as fuel. In order to avoid condensation in the flow path L1 and ensure a predetermined concentration, it is necessary for the carrier gas to maintain a temperature equal to or higher than the condensation temperature of the combustible organic substance. Since the exhaust gas temperature from the combustion apparatus 2 is 200 to several hundreds of degrees Celsius and can be maintained at about 80 to 100 degrees Celsius exceeding the condensation temperature of the organic substance, such conditions have been seen,
That is, it is possible to avoid the risk of backfire as a low oxygen-containing gas and to promote the vaporization of the combustible organic substance using the latent heat of the exhaust gas and to suppress the condensation in the flow path.

[About ultrasonic atomizer]
As shown in FIG. 2, the ultrasonic atomizer 1 includes an ultrasonic transducer 11 and a liquid container 12. The principle or operating conditions (vibration frequency, etc.) of ultrasonic atomization are described in detail in the above-mentioned prior art documents, and thus are omitted in this specification. As the ultrasonic transducer 11, a known ultrasonic transducer can be used. Moreover, although the ultrasonic transducer | vibrator 11 is installed in the bottom part of the liquid container 12, you may install in parallel with a bottom part and may install it diagonally. The atomized body can be generated better when installed obliquely. A plurality of ultrasonic transducers 11 may be installed. When a plurality of ultrasonic transducers 11 are installed obliquely, it is preferable to install them so that the liquid columns do not interfere with each other. Further, the ultrasonic vibration force is controlled by the control unit 3, and is completely stopped when the oxygen concentration in the carrier gas exceeds a predetermined value or when a backfire is detected in the fuel supply flow path L1. There is.

  The liquid container 12 is provided with a liquid fuel introduction part 1a for supplying liquid fuel. The liquid fuel introduction part 1a is preferably installed on the lower side of the liquid level because the liquid flow can be reduced. Further, the liquid container 12 has an atomized body for providing the combustion device 2 with the carrier gas introducing portion 1b for introducing the carrier gas into the interior above the liquid level and the generated atomized body. The delivery part 1c is provided. The size, material, and the like of the liquid container 12 are not particularly limited as long as they can withstand the exhaust gas temperature, and can be set according to the specifications of the liquid fuel and the combustion device 2.

  The ultrasonic atomizer 1 also includes an atomizer concentration detection means (not shown) for detecting the atomized material concentration (combustible organic substance-containing concentration), the liquid container 12 inside, the atomized material delivery unit 1c. Or it is preferable to install in fuel supply flow path L1 grade | etc.,. The atomized body supply amount to the fuel device 2 can be monitored, and transient control such as the heat generation amount of the fuel device 2 can be appropriately performed. As the detection means, for example, when alcohols are contained as combustible organic substances, an alcohol concentration detector can be used.

  Furthermore, it is preferable to control the liquid temperature of the liquid container 12 according to the concentration value detected above. The liquid temperature can be adjusted by providing an electric heating jacket (not shown) on the wall surface of the liquid container 12 and controlling it. Moreover, it is preferable to similarly control the temperature of the liquid in the liquid fuel supply device 6 and the supply flow path L5. When the liquid temperature is, for example, a concentration value of about 60 mol% or less, an atomized body having a stable concentration and a stable property can be generated by controlling the liquid temperature within a range of 5 to 50 ° C.

  Moreover, it is preferable that the ultrasonic atomizer 1 includes a liquid level detector (not shown) that detects the liquid level height h (distance from the ultrasonic transducer 11 to the liquid level) of the liquid. For liquid fuels containing arbitrary organic substances, the correlation between the liquid level height, ultrasonic vibration force (and liquid temperature) and the concentration of the atomized body is obtained, and the desired liquid level height is obtained. By controlling the ultrasonic vibration force for securing the atomized body concentration or controlling the flow rate of the carrier gas supplied to the fuel device 2 from the atomized body concentration at a predetermined ultrasonic vibration force, It is possible to supply the atomized material with the optimum conditions that meet the specifications. The liquid level detection means is not particularly limited, and a known liquid level detection device can be applied. For example, an ultrasonic level sensor, a floating type detector, or the like can be used. It is also possible to control the amount of liquid combustion supplied from the liquid supply device 6 so as to keep the liquid level height detected above constant. For example, when the above-described ultrasonic vibrator is used, the liquid level is preferably 40 mm or less, preferably 20 mm or less.

[Combustion device]
In FIG. 1, the combustion apparatus 2 is a burner, for example. In order to obtain the required combustion amount in the combustion device 2, the supply amount of the carrier gas including the atomized body is set. At this time, it is preferable that the combustion apparatus 2 maintains a stable combustion state by supplying fuel A (corresponding to the second fuel) from the fuel supply unit 2c and combustion air from the air supply unit 2d. Regardless of whether or not the atomized body is supplied, by securing a predetermined amount of combustion in the combustion device 2, a combustion amount that is greater than the supply amount of liquid fuel is required, at the start-up of the combustion system, or the liquid fuel Even in the case where there is a fluctuation in the supply amount, the combustion amount can be secured by the combustion device 2 alone. In this case, since the exhaust gas contains carbon dioxide, water, or nitrogen and excess oxygen generated by the reaction between the fuel A and the combustion air, the excess oxygen concentration is reduced under the condition of no supply of the atomized body. By setting the combustion conditions of the combustion device so as to be within the safe concentration range of the ultrasonic atomizer 1, it becomes possible to ensure the safety of the entire combustion system. That is, when the atomized body is supplied, a part of the excess oxygen is consumed for the combustion, and the oxygen concentration in the exhaust gas becomes lower than the set value and shifts to a safer side.

Specifically, when the waste heat recovery device 4 is a boiler with an evaporation amount of 2000 kg / h, 90% of the heat amount is supplemented with fuel A, and the remaining 10% is supplemented with a combustible organic substance (for example, ethanol). In this case, it is necessary to supply about 35 kg / h of an atomized body having an ethanol concentration of 60 Vol%. The air equivalent amount required as the carrier gas of the ultrasonic atomizer 1 is 1 to 2.5 m ³ N / kg-atomized body. Since combustion air is a 3.0-3.5m < ³ > N / kg-atomization body, it is possible to cover conveyance air with a part of combustion air.

[About the flame detector]
The flame detector S1 is not particularly limited as long as it is a member that has resistance to the gas containing the atomized body and does not affect the gas. For example, the responsiveness to the flame is confirmed in advance. Temperature sensors, electrode-type flame detectors that detect ions in the flame, photo-detection type flame detectors that detect ultraviolet and infrared rays emitted from the flame, or multiple optical fibers in this application. A flame detector or the like that detects flicker can be used. In particular, the method for detecting light emission from a flame is excellent in safety and resistance because it can be detected in a non-contact manner with a test gas.

[About the oxygen measuring unit]
The oxygen measuring unit S2 is not particularly limited as long as the oxygen measuring unit S2 is a member that has resistance to a gas containing an atomized body and does not affect the gas. For example, a magnetic oxygen meter or a zirconia type An oxygen meter or the like can be used. In particular, in order to ensure safety, a continuous measurement type oxygen meter is preferable.

[About the organic substance measurement unit]
In the present combustion system, the organic substance measuring unit S3 often targets a specific organic substance such as alcohol, so that it is not necessary to selectively measure various components individually using a chromatograph. Therefore, it is not particularly limited as long as it is a member that has resistance to a gas containing an atomized body and does not affect the gas. For example, an infrared hydrocarbon analyzer or a conductivity measuring instrument. Or a combustion type hydrocarbon meter etc. can be used. In particular, in order to ensure safety, an infrared analyzer capable of continuous measurement without contact is preferable.

[Constituent elements in this combustion system]
For supply of the carrier gas, the above-described air supply fan F, a compressor of the carrier pressure source, or the like can be used as a carrier means. In addition, a combustion gas flow control mechanism (orifice, flow control valve, etc.), a temperature control mechanism (heat exchanger 5, etc.) and the like are provided, and in the present combustion system, an oxygen measuring unit S2 is provided and contained combustion. The risk of fire and flashback due to volatile organic substances is avoided. However, as will be described later, when the exhaust gas temperature supplied to the ultrasonic atomizer 1 is relatively low (approximately 80 to 100 ° C.), the heat exchanger 5 is not required. As the temperature adjusting mechanism, in order to control the temperature of the carrier gas, it is preferable to provide a temperature measuring means (not shown) in the carrier gas flow path L3, and the carrier gas temperature in the carrier gas flow path L3 is ultrasonically adjusted. It is preferable that the temperature is higher by about 10 to 20 ° C. than the temperature in the atomizer 1.

  The carrier gas flow rate control mechanism and the temperature control mechanism are controlled by the controller 3. The control unit 3 can be configured by a cooperative action of a hardware resource such as a CPU and a memory and a software program for realizing these functions, and can also be configured by a dedicated circuit, firmware, or the like.

<Utilization method of liquid fuel using this combustion system>
Next, a method of using liquid fuel using this combustion system will be described. In the method of using liquid fuel using the present combustion system, in addition to using the exhaust gas from the combustion device 2 that is a low oxygen-containing gas with a low risk of flashback as described above, the following functions are provided. It is characterized by having.

(I) Control of atomization body supply to fuel device using oxygen concentration in carrier gas as index As a safety net on the supply side to ultrasonic atomizer 1 for the use of low oxygen-containing gas as carrier gas, oxygen The oxygen concentration in the carrier gas is measured by the measuring unit S2, and the ultrasonic atomization apparatus 1 is stopped and the ultrasonic vibration force is controlled, or the supply of the carrier gas is stopped and the supply amount is controlled. That is, when the measured value exceeds, for example, the lower explosion limit of the flammable organic substance in the liquid fuel, the atomization body may be ignited or backfired from the ultrasonic atomizer 1 in the fuel supply flow path L1. Specifically, if there is a possibility of lack of safety due to a sudden change in oxygen concentration, the ultrasonic wave and the carrier gas are stopped at the same time, even if the oxygen concentration is within the limit value. When sudden changes occur, the supply amount of the carrier gas or the ultrasonic vibration force is reduced to ensure the stability of the combustion conditions of the combustion device 2 and to stabilize the oxygen concentration in the exhaust gas. The safety of the system can be ensured. For example, in the case of liquid fuel containing ethyl alcohol, the oxygen concentration in the carrier gas is 0 to 8%, and the control range of the ultrasonic wave and the carrier gas is set. Ensure safety by controlling

(Ii) Monitoring and supply control of flames in the fuel supply flow path from the ultrasonic atomizer to the combustion device As a safety net on the delivery side of the ultrasonic atomizer 1 that delivers a gas containing a high concentration organic substance, Control is performed to detect a flame in the fuel supply flow path L1 from the sonic atomizer 1 to the combustion apparatus 2 and to block backfire in the flow path. That is, the backfire of the flame from the combustion device 2 or the generation of flame due to condensation of the atomized body or adhesion of droplets in the fuel supply flow path L1 is caused by the ultrasonic atomizing device 1 in which a predetermined amount of liquid fuel is stored. Secondary danger may occur, and such danger can be avoided in advance by the safety net on the supply side. In particular, by combining with the control function (i), a safety mechanism for both the supply side and the supply side of the ultrasonic atomizer 1 can be configured, and higher safety can be ensured.

(Iii) Control of recovery and reuse of effluent after atomization In the treatment of effluent after atomization in ultrasonic atomizer 1, the combustion contained in the effluent by organic substance measuring unit S3 The concentration of the organic organic substance is detected, and when the concentration is lower than the predetermined concentration, it is collected as a highly safe effluent. For example, in the case where liquid fuel containing organic substances such as benzene and phenols is targeted, the concentration of the organic substances in the wastewater is the discharge standard concentration of wastewater (for example, benzene: 0.1 mg / L, phenols: 5 mg). / L) In the following cases, it can be discarded as an effluent purified by an atomization process. On the other hand, when the concentration of the organic substance exceeds the emission standard concentration, further purification treatment is required, but the organic substance contained therein is still valuable as a fuel. By recirculating to 1 and performing the atomization again (repeatedly), it can be effectively used as fuel. In this way, the liquid containing the combustible organic substance can be effectively utilized to the maximum extent.

[How to operate this combustion system]
In this combustion system, it is possible to perform system startup operation, steady operation, and shutdown operation that effectively utilize the above-described configuration and functions. That is, it is preferable to perform each operation as follows.

(I) Combustion system start-up operation When the ultrasonic atomizer 1 is switched from the ultrasonic OFF state to the ON state, a predetermined time is required until the generation amount of the atomized body from the liquid fuel is stabilized. To do. In addition, when the carrier gas is supplied from the carrier gas flow path L3 to the ultrasonic atomizer 1 in a state where the combustion device 2 is not started up, an insufficient atomization treatment or a low temperature at which a desired organic substance concentration cannot be obtained. There is a possibility of causing condensation of the atomized body or generation of droplets in the fuel supply flow path L1 due to the carrier gas. In this combustion system,
(I-1) The temperature of the system consisting of the combustion device 2 that supplies the fuel A and the combustion air to the combustion device 2 and includes the exhaust gas supply to the waste heat recovery device 4 and the exhaust gas flow path L2 and the waste heat recovery device 4 Stabilize the flow rate.
(I-2) Under the condition that the system is stable, the air supply fan F is turned on, and a part of the exhaust gas from the combustion device 1 is supplied as a carrier gas to the ultrasonic atomizer 1, and the ultrasonic atomizer 1. Stabilize the temperature and flow rate of the system composed of 1-fuel supply flow path L1-combustion device 2-exhaust gas flow path L2-carrier gas flow path L3.
(I-3) When the above two systems are stabilized, the ultrasonic wave of the ultrasonic atomizer 1 is turned on so that an atomized body having a stable organic substance concentration can be obtained in a relatively short time. Can be conveyed.
At this time, the measurement of oxygen concentration in the carrier gas and the monitoring of the flame play an important role as a response to the transient phenomenon at the initial action such as the occurrence of an abnormality of the atomized body, especially when the ultrasonic wave is turned on. There is.

(Ii) Steady operation of combustion system Under the above-mentioned stable conditions, ultrasonic vibration force or / and ultrasonic fog supplied according to the combustion amount of the combustion device 2 and the required heat generation amount of the waste heat recovery device 4 It is preferable to control the flow rate of the exhaust gas conveyed to the gasification apparatus 1. In addition, with respect to the liquid atomized by the ultrasonic atomizer 1, the control is performed by switching between the recovery operation as the discharged liquid and the recirculation operation for the re-atomization process using the organic substance concentration in the wastewater as an index. It is preferable to do.

(Iii) Combustion system deactivation operation In decommissioning the combustion system, it is necessary to consider safety and smoothing of the next activation operation. From the viewpoint of safety, there is a method of operating in the reverse order of the above (i) start-up operation.
(Iii-1) First, the supply of liquid fuel is stopped, and the recirculation system is operated until the liquid inside the ultrasonic atomizer 1 can be discharged as the discharged liquid.
(Iii-2) When it becomes possible to discharge as discharged liquid, the ultrasonic wave is stopped and generation and supply of the atomized body are stopped.
(Iii-3) The supply of fuel A to the combustion device 2 is stopped, and the system comprising the ultrasonic atomizer 1-fuel supply flow path L1-combustion device 2-exhaust gas flow path L2-carrier gas flow path L3 Reduce temperature.
(Iii-4) Supply of the combustion air of the combustion apparatus 2 is stopped, and the liquid inside the ultrasonic atomizer 1 is discharged as the discharged liquid.
(Iii-5) Supplying combustion air of the combustion device 2 to clean the system composed of the ultrasonic atomizer 1-fuel supply flow path L1-combustion device 2-exhaust gas flow path L2-carrier gas flow path L3 To do.
(Iii-6) Supply of the combustion air of the combustion device 2 is stopped, and a cleaning liquid is supplied from the liquid fuel introduction part 1a instead of the liquid fuel to clean the inside of the ultrasonic atomizer 1.

DESCRIPTION OF SYMBOLS 1 Ultrasonic atomizer 1a Liquid fuel introduction part 1b Carrier gas introduction part 1c Atomization body delivery part 1d Liquid discharge part 2 Combustion device 2a Atomization body supply part 2b Exhaust gas discharge part 2c Fuel supply part 2d Air supply part 3 Control part 4 Waste heat recovery device 5 Heat exchanger F Air supply fan (conveyance means)
L1 Fuel supply flow path L2 Exhaust gas flow path L3 Carrier gas flow path L4 Drainage flow path L5 Circulation flow path P Drainage pump S1 Flame detection section S2 Oxygen measurement section S3 Organic substance measurement section V1 On-off valve V2 Switching valve

Claims (6)

A liquid containing low combustible organic matter is atomized using an ultrasonic atomizer,
The high-concentration combustible organic-containing atomized body obtained by the atomization is supplied as a fuel for the combustion apparatus using a carrier gas, and the treatment liquid after the atomization is disposed as an exhaust liquid. In the usage of liquid,
While using the exhaust gas from the combustion device as the carrier gas,
When the oxygen concentration in the exhaust gas is measured and the measured value exceeds a predetermined value, the ultrasonic atomization of the ultrasonic atomizer is stopped, the ultrasonic vibration force is controlled, and / or the supply of the carrier gas is stopped. A method of using a liquid containing a low-concentration combustible organic substance, wherein the supply amount is controlled.   The low-concentration combustion according to claim 1, wherein a flame in a fuel supply channel from the ultrasonic atomizer to the combustion device is monitored and the fuel supply channel is shut off when a flame is detected. To use liquid containing organic organic substances Supplying the second fuel and combustion air to the combustion device to ensure the amount of combustion necessary for the combustion device;
In a state where the flow rate and temperature of the exhaust gas conveyed to the ultrasonic atomizer is stable, supply ultrasonic waves of the ultrasonic atomizer,
The low-concentration combustion according to claim 1 or 2, wherein the ultrasonic vibration force supplied and / or the flow rate of exhaust gas conveyed to the ultrasonic atomizer is controlled according to the combustion amount of the combustion device. To use liquid containing organic organic substances   The ultrasonic atomizer detects the concentration of the combustible organic substance contained in the treatment liquid after the atomization treatment. If the concentration is lower than the predetermined concentration, the concentration is recovered as the discharged liquid. The method for using a low-concentration combustible organic substance-containing liquid according to any one of claims 1 to 3, wherein the liquid is supplied to a sonic atomizer and recirculated. An ultrasonic atomizer that atomizes a liquid containing a low-concentration combustible organic substance, and an atomized body containing a high-concentration combustible organic substance obtained by the atomization using a carrier gas as a fuel for the combustor A combustion system to supply as
A carrier gas passage connecting the combustion exhaust gas discharge part of the combustion device and the ultrasonic atomizer, and exhaust gas from the combustion device is supplied to the ultrasonic atomizer as the carrier gas via the carrier gas passage. A conveying means for performing the measurement, and an oxygen measuring unit for measuring the oxygen concentration in the exhaust gas,
When the measured value of the oxygen measuring unit exceeds a predetermined value, the ultrasonic atomizer is stopped or the ultrasonic vibration force is controlled or / and the carrier gas supply is stopped or the supply amount is controlled. A combustion system using a liquid fuel containing a low-concentration combustible organic substance, characterized by comprising a part. A fuel supply channel that supplies atomized material from the ultrasonic atomizer to a combustion device, a flame detection unit that monitors the occurrence of a flame in the fuel supply channel or the escape of the flame, and the fuel supply channel. An on-off valve that shuts off,
6. The low-concentration combustible organic substance-containing liquid fuel according to claim 5, wherein when the flame detection unit detects a flame, the fuel supply flow path is blocked by braking the on-off valve by the control unit. Combustion system.

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