JP2003083949A - System for measuring floating substance in fine particle shape for ship, and exhaust gas dilution equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a measurement system of a floating substance in a fine particle shape for ships that can measure the floating substance in a fine particle shape in an exhaust gas easily even on a ship that oscillates conforming to the regulation of the International Standardization Organization. SOLUTION: The system comprises a dilution air supply apparatus 3 having a dry cleaning apparatus 31 and an amount-of-supply adjustment valve 32, exhaust gas dilution equipment 4 for mixing clean air that is transmitted from the dilution air supply apparatus 3 and the exhaust gas in an engine, a carbon gas-measuring instrument 10 for measuring a carbon dioxide gas contained in the exhaust gas in the engine or a diluted exhaust gas that is transmitted from the exhaust gas dilution equipment 4 via a switching cock 8 and a pretreating apparatus 9, and a beta ray absorption type floating fine particle-like substance measuring instrument 5 for measuring floating substances in a fine particle shape in the diluted exhaust gas that is transmitted from the exhaust gas dilution equipment 4. A dilution coefficient is obtained from the carbon dioxide gas measurement value of the exhaust gas of the engine and the diluted exhaust gas by the carbon dioxide gas-measuring instrument 10, and the amount of transmission of clean air in the dilution air supply apparatus 3 is adjusted so that the dilution coefficient becomes an appropriate one.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a measuring system for airborne particulate matter in exhaust gas of a marine engine and an exhaust gas diluter used in the measuring system.

[0002]

2. Description of the Related Art Floating particulate matter is said to adversely affect the global environment or the human body. Most of the ships are operated by diesel engines, and low-quality fuel, which is said to generate a lot of airborne particulate matter, is used in many cases, but their actual emissions have not been clarified. This is partly due to the fact that measuring instruments suitable for measurement on ships have not been developed.

There are few examples of measurement of airborne particulate matter on a ship, but an example of measurement by mounting a dilution tunnel in accordance with the regulations of the International Organization for Standardization on a ship, or an ejector type diluter and filter vibration type. There is an example of measurement by mounting an automatic measurement system for ship particle concentration, which is a combination of measuring instruments for airborne particulate matter.

However, since the measurement of airborne particulate matter by a dilution tunnel is presumed to be a land-based engine, it requires a large-scale device to be mounted on a vessel for measurement, and the loading / unloading or installation location. Be restricted by. In addition, after maintaining a constant temperature and humidity with a thermo-hygrostat before and after using the filter used to collect airborne particulate matter,
Since it is necessary to weigh with a precision balance, the measurement result cannot be instantaneously obtained on the ship.

An automatic particle concentration measuring system for ships, which is a combination of an ejector diluter and a filter vibration type floating particulate matter measuring instrument, is compact and is advantageous at the loading / unloading or installation site. In addition, the measurement result is instantly indicated, which is advantageous for grasping the progress of the discharge state of the airborne particulate matter.

However, in the filter vibration type floating particulate matter measuring device, the weight is obtained by utilizing the fact that the natural frequency of the taper element attached to the collection filter changes due to the collection of the floating particulate matter. Because it is
Since the indicated value is greatly affected by the shaking of the hull, it is impossible to measure it when shaking is involved.

Further, the ejector type diluter of the ship particle automatic concentration measuring system has a constant diluting coefficient under the condition that it is used for a certain range of diluting air flow under normal temperature and pressure by reducing the diameter of the ejector nozzle. Is designed to be. However, the exhaust gas of a diesel engine has a drawback in that, when the conditions are different from those described above, a large amount of airborne particulate matter is precipitated in the ejector nozzle having a small pipe diameter, and accurate measurement cannot be performed.

Further, the International Organization for Standardization stipulates that the suction is performed at the same speed as the exhaust gas, but in the ejector diluter of the ship particle automatic concentration measurement system, the exhaust gas flowing through the exhaust pipe of the diesel engine is When suctioning, the ability is not sufficient to perform constant-speed suction as defined by the International Organization for Standardization.

[0009]

SUMMARY OF THE INVENTION Therefore, the present invention is capable of easily measuring the floating particulate matter in the exhaust gas according to the provisions of the International Organization for Standardization even on a ship accompanied by shaking. An object of the present invention is to provide a substance measurement system and an exhaust gas diluter useful for implementing the system.

[0010]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems. The first invention is a dilution air supply device having a dry cleaning device and a supply amount adjusting device, and this dilution air supply device. An exhaust gas diluter that mixes clean air sent from the air supply device and engine exhaust gas, a carbon dioxide gas contained in the exhaust gas of the engine or the diluted exhaust gas sent from the exhaust gas diluter, and a switching cock and a pretreatment device. A carbon dioxide gas measuring device for measuring via a carbon dioxide gas measuring device, and a beta ray absorption type floating fine particle measuring device for measuring floating fine particles in the diluted exhaust gas sent from the exhaust gas diluter. From the measured values of carbon dioxide gas of the engine exhaust gas and diluted exhaust gas measured by, the dilution coefficient is obtained, and the dilution air supply device is adjusted so that the dilution coefficient becomes an appropriate dilution coefficient. A floating particulate matter measurement system for vessels, which comprises adjusting the purification air delivery quantity.

A second aspect of the present invention is an exhaust gas diluter useful for carrying out the first aspect of the present invention, in which one end of a main body provided with a mixing chamber is inclined from several places around the exhaust gas inflow path toward the jet outlet side thereof. An air gun equipped with a nozzle for ejecting clean air is installed on the opposite side, and an outlet nozzle is provided on the opposite side with the separation tube protruding toward the inside of the mixing chamber. An exhaust gas diluter having an overflow discharge port.

The floating particulate matter measuring system for a ship according to the first aspect of the invention is intended to collect the exhaust gas flowing through the exhaust pipe of a diesel engine on a ship and measure the floating particulate matter in the exhaust gas. As a measuring instrument, a beta ray absorption type floating particulate matter measuring instrument used for measuring airborne particulate matter (dust) was selected and used. The main part of this measuring instrument consists of a suspended particulate matter trapping mechanism, a filter paper feeding mechanism, a beta ray source and detector, and an arithmetic controller, all of which are fixed during measurement.
Moreover, since there are no movable parts, it is not easily affected by shaking. Moreover, the size of the filter vibrating particulate matter measuring device is comparable to that of the filter vibrating type particulate matter measuring device, and it is easy to carry in / out and select the installation place. In addition, the beta ray absorption type suspended particulate matter measuring device is capable of continuous measurement, so this was made a component of the system.

However, since this beta ray absorption type buoyant particulate matter measuring instrument measures dust in the atmosphere, it cannot be used as it is for exhaust gas of a marine engine. .

When the exhaust gas of a marine engine is used, it is necessary to measure the exhaust gas in a diffused state in the atmosphere, that is, in a diluted state. Therefore, the exhaust gas diluter is used in the measurement system of the present invention.

However, when a known ejector type diluter is used as the exhaust gas diluter, the exhaust gas pressure in the exhaust pipe of the diesel engine changes depending on the load state, and accordingly, the dilution coefficient of the ejector diluter changes. The problem arises. Therefore, in the present invention, in order to solve this problem, the present invention measures the carbon dioxide concentration x in the exhaust gas of a diesel engine, and additionally provides a sampling port for measuring carbon dioxide in the body of the ejector diluter to measure the carbon dioxide concentration in the diluted exhaust gas. x'is measured,
Dilution coefficient x /
The problem is solved by finding x ′ and setting the supply amount of the dilution air so that the dilution coefficient becomes an appropriate value (set to 4 or more according to the rule).

Further, with respect to the speed of the exhaust gas flowing through the exhaust pipe of the diesel engine, the problem that the ejector type diluter does not have sufficient capacity to perform constant velocity suction, and in the present invention, the air gun type exhaust gas diluter was developed and used. .

The cylinder of this exhaust gas diluter is the same size as the ejector diluter, and one end of the cylinder is equipped with this commercially available air gun. This air gun is originally used for cleaning, transporting or spraying powder, particles, smoke and the like.

Therefore, if an air gun having a suction capacity adapted to the exhaust gas velocity of the diesel engine is used, uniform velocity suction can be easily performed, and the flow rate of the exhaust gas can be adjusted by adjusting the amount of clean air sent from the dilution air supply device. By adjusting and changing the amount, the amount of exhaust gas to be sucked can be adjusted, and it is possible to suck at a constant speed.

Further, since the minimum inner diameter is larger than that of other pipes, the deposition of suspended particulate matter is small. Although the dilution coefficient changes due to this, the correction is easy because the dilution coefficient is obtained from the carbon dioxide gas concentration as described above.

[0020]

1 is a block diagram showing the overall construction of an embodiment of the present invention. 1 is an exhaust pipe of a diesel engine, 2 is a measurement probe for buoyant particulate matter, and 3 is a dry probe. The dilution air supply device includes a cleaning unit 31 and a valve 32 (supply amount adjusting device).

Reference numeral 4 is an exhaust gas diluter, 5 is a beta-ray absorption type floating particulate matter measuring instrument comprising a suspended particulate matter trapping mechanism, a filter paper supply mechanism, a beta ray source and a detector, and an arithmetic controller, and 6 is the above-mentioned. A suction pump controlled by an arithmetic controller, 7 is a probe for measuring carbon dioxide gas, 8 is a switching cock, 9 is a pretreatment device, and 10 is a carbon dioxide measuring device.

FIG. 2 is a detailed view of the exhaust gas diluter 4, which shows the main body 4
A mixing chamber 42 and a separation chamber 43 communicating with the mixing chamber 42 are provided in the body of No. 1.
The air gun 11 is attached to the upper end of the main body 41.

The exhaust gas taken out from the exhaust pipe 1 is sucked from the suction port 11a of the air gun 11 and jetted into the mixing chamber 42 from the jet port 11b. Then, the clean air supplied from the dilution air supply device 3 passes through the intake port 11c of the air gun 11 and the axial center from four nozzles N1, N2, N3, N4 (not shown) obliquely provided in the injection port 11b direction. Toward the interior of the mixing chamber 42 and is mixed with the exhaust gas to dilute the exhaust gas.

At the lower end of the body 41, a mixing chamber 42
An outlet nozzle 45 having a separation pipe 44 protruding is provided in a separation chamber 42 communicating with the separation chamber 42, and a main body 41 on the side of the separation pipe 44 is provided with a carbon dioxide gas measurement collection port 46 and an overflow discharge port 47. .

The above-described structure is used for discharging the measurement diluted exhaust gas containing no water droplets from the outlet nozzle 45, and for discharging the remainder of the diluted exhaust gas into the atmosphere from the overflow outlet 47. This is because the inside is set to the atmospheric pressure and the diluted exhaust gas taken out from the outlet nozzle 45 can be measured by the beta ray absorption type floating particulate matter measuring device 5.

The operation of the whole floating particulate matter measurement system for a ship shown in the embodiment is performed by the exhaust pipe 1 of the diesel engine.
When part of the exhaust gas is guided to the exhaust gas diluter 4 from the buoyant particulate matter measuring probe 2 attached to the exhaust gas diluter 4, the exhaust gas is diluted with clean air. Then, the diluted exhaust gas is supplied to the main body 4 of the exhaust gas diluter 4.
From the outlet nozzle 45 provided in the body of No. 1 to the beta ray absorption type floating particulate matter measuring instrument 5, the concentration of the floating particulate matter in the exhaust gas diluted here is measured and used for the measurement. The diluted exhaust gas is discharged into the atmosphere by the suction pump 6.

Next, the measurement of the carbon dioxide concentration in the exhaust gas of the diesel engine and the diluted exhaust gas will be described.

A part of the exhaust gas reaches the carbon dioxide measuring instrument 10 from the carbon dioxide measuring probe 7 attached to the exhaust pipe 1 through the switching cock 8 and the pretreatment device 9, and the carbon dioxide concentration X is measured there.

On the other hand, a part of the diluted exhaust gas reaches the carbon dioxide measuring instrument 10 through the carbon dioxide measuring sampling port 46 provided in the body of the exhaust gas diluter 4 through the switching cock 8 and the pretreatment device 9, and here. The carbon dioxide concentration x'is measured, the dilution coefficient x / x 'is obtained as described above, and the valve 32 is adjusted so that the dilution coefficient becomes 4 or more.

Next, the operation of the exhaust gas diluter 4 will be described. The exhaust gas is guided to the suction port 11a of the air gun 11. On the other hand, the compressed air that has become clean air in the dry cleaning unit 31 is guided from the air supply port 11c of the air gun 11 to the nozzles N1 to N4 to suck the exhaust gas and at the same time mix it with the exhaust gas from the injection port 11b. Eject to 42. In the mixing chamber 42, the discharged exhaust gas and the clean air are uniformly mixed here, and become diluted exhaust gas.

Then, a part of the diluted exhaust gas escapes to the atmosphere through an overflow outlet 47 provided in the cylinder. At the same time, the pressure of the mixing chamber 42 is kept at atmospheric pressure, and the measurement conditions of the beta ray absorption type floating particulate matter measuring instrument 5 are adjusted. Then, the diluted exhaust gas is guided to the beta ray absorption type floating particulate matter measuring instrument 5 from an outlet nozzle 45 provided at the lower part of the body, and the floating particulate matter is measured.

[0032]

[Effects of the Invention] In an experimental medium-sized medium-speed 4-cycle diesel engine, a comparison was made between an engine-specific dilution tunnel and the ship floating particulate matter measurement system according to the present invention. The results of measurement of airborne particulate matter emission concentrations were in agreement. From this, it can be said that the measurement results of the floating particulate matter measurement system for ships according to the present invention comply with the regulations of the International Organization for Standardization.

A filter vibration type floating particulate matter measuring instrument and a beta ray absorption type floating particulate matter measuring instrument were actually mounted on a ship and comparative measurement was carried out. Although the natural frequency of the taper element changed with the fine particle measuring instrument, the zero point of the beta ray absorption type floating particulate matter measuring instrument did not change, and the measurement was possible even when the ship was swaying.

Therefore, the buoyant microscopic particulate matter measuring system for a ship according to the present invention having the beta ray absorption type buoyant particulate matter measuring device as one of its constituent elements can be applied to the measuring side of a ship, It becomes possible to investigate the actual discharge of airborne particulate matter discharged from ships, and the actual discharge becomes clear.

[Brief description of drawings]

FIG. 1 is a block diagram showing the overall configuration of an embodiment of the present invention.

FIG. 2 is an enlarged sectional view showing details of an exhaust gas diluter.

[Explanation of symbols]

1 exhaust pipe 2 Probe for measuring airborne particulate matter 3 dilution air supply device 31 Dry Cleaning Unit 32 valves 4 Exhaust gas diluter 41 body 42 mixing chamber 43 Separation chamber 44 Separation tube 45 outlet nozzle 46 Sampling port for measuring carbon dioxide 47 Overflow outlet 5 Beta-ray absorption type floating particulate matter measuring instrument 6 suction pump 7 Carbon dioxide measurement probe 8 switching cock 9 Pretreatment equipment 10 Carbon dioxide measuring instrument 11 Air Gun 11a suction port 11b injection port 11c Air supply port

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 2G001 AA03 BA11 CA03 KA01 MA04                       PA11 RA08                 2G052 AA02 AB22 AC19 AD04 AD24                       AD44 BA05 BA14 CA03 CA04                       CA11 DA22 EA03 FB02 FB09                       GA09 GA19 HA15 HC02 HC09                       HC24 HC43 JA04

Claims (2)

[Claims] 1. A dilution air supply device including a dry cleaning device and a supply amount adjustment device, an exhaust gas diluter for mixing clean air sent from the dilution air supply device and engine exhaust gas, and exhaust gas of the engine or A carbon dioxide gas measuring device for measuring carbon dioxide gas contained in the diluted exhaust gas sent from the exhaust gas diluter via a switching cock and a pretreatment device, and floating fine particles in the diluted exhaust gas sent from the exhaust gas diluter. Equipped with a beta ray absorption type floating particulate matter measuring device for measuring a substance, the dilution coefficient is obtained from the carbon dioxide measurement value of the engine exhaust gas and diluted exhaust gas measured by the carbon dioxide measuring device, and the dilution coefficient is an appropriate dilution. A floating airborne particulate matter measuring system for a ship, wherein the amount of clean air delivered from the dilution air supply device is adjusted so as to obtain a coefficient. 2. At one end of the body with a mixing chamber,
An air gun equipped with a nozzle that jets clean air diagonally from several places around the exhaust gas inflow path toward the jet outlet side,
Exhaust gas dilution characterized in that an outlet nozzle with a separation pipe protruding toward the inside of the mixing chamber is provided on the opposite side, and a carbon dioxide gas measurement sampling port and an overflow discharge port are provided on the side body of the separation pipe. vessel.