JP3015642B2 - Gas sampling method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for sampling gas in a reaction process for gas analysis or the like.

[0002]

2. Description of the Related Art Sampling of a combustion gas is performed to analyze the concentration of oxygen in a gas during the reaction process, for example, the combustion gas. For sampling of such combustion gases,
As shown in FIG. 2, a water supply source 1, a gas sampling pipe 2,
A method using a gas sampling device in which the gas branch pipe 3 and the water ejector 4 are connected by the pipe 5 in this order is adopted.

[0003]

However, dust such as coal ash is contained in the above-mentioned combustion gas. Parts are included as dust. There is a problem that the dust is sucked from the gas sampling pipe 2 and enters the water ejector 4 to block the orifice portion.

[0004]

Means for Solving the Problems Accordingly, the present inventors have:
As a result of various studies to solve the problem of the method using the conventional sampling device described above, by using a self-priming water pump instead of the water ejector, there is no problem such as blockage due to dust, and continuous It was found that gas sampling could be performed by using this method, and the present invention was proposed.

That is, according to the present invention, a water supply source, a gas sampling pipe, a gas branch pipe and a self-priming water pump are connected in this order by piping, and a water supply pipe is connected to a water filling port of the self-priming water pump. Gas sampling characterized by using a sampling device in which a pipe from a gas branch pipe is connected to the water suction port, and sampling while always supplying water to the water filling port while the self-priming water pump is operating. Is the way.

The present invention will be described below in detail with reference to the drawings. FIG. 1 is a schematic diagram of an apparatus used for the gas sampling method of the present invention. As shown in FIG. 1, a water supply source 1, a gas sampling pipe 2, a gas branch pipe 3, and a self-priming water pump 6 are connected in this order by a pipe 5. The water supply source 1 may be any as long as it has a function of supplying water to the gas sampling pipe 2. For example, it may be a water storage tank, a water distribution pipe, or the like.

The gas sampling tube 2 is fixed so that the tip is located at a gas sampling point, and gas to be sampled is sucked from the tip. Gas sampling pipe 2
Is preferable to reduce the amount of dust accompanying the gas when the gas to be sampled contains dust. For example, a gas sampling pipe having a double pipe structure composed of an inner pipe 7 and an outer pipe 8, in which the tip of the inner pipe 7 is protruded from the tip of the outer pipe 8, and a number of holes are formed around the tip, is preferable. Can be used for The gas to be sampled is drawn from the outer tube 8. The inner pipe 7 is connected to the water supply source 1, and the gas sucked from the outer pipe 8 is washed by water jetted from around the tip of the inner pipe 7, and dust and the like contained in the gas are washed away. Further, it is possible to prevent dust from entering the gas sampling pipe.

[0008] When sampling the combustion gas with the apparatus used in the gas sampling method of the present invention, the gas sampling tube is installed in the high-temperature combustion gas. In this case, it is preferable that the gas sampling pipe has a triple structure and the outermost pipe 9 allows cooling water to pass therethrough.

The gas to be sampled is sucked from the outer pipe 8 together with a part of the water jetted from the inner pipe 7 of the gas sampling pipe 2 and the gas sampling pipe 2, the gas branch pipe 3 and the self-priming water pump 6 are moved. It passes through the connecting pipe 5. In the gas branch pipe 3, part of the gas in the mixture of gas and water is branched and sent to a gas branching device or the like. On the other hand, the mixture of water and gas after a part of the gas is separated by the gas branch pipe 3 is sucked by the self-priming water pump.

The self-priming water pump of the apparatus used in the present invention comprises a water suction port 10, a water discharge port 11, and a water filling port 1.
2, water is sucked from a water suction port 10, and a water discharge port 11
Any pump having a function of discharging the water sucked from the pump can be used without any limitation.

The pump of the type that sucks water by the rotating blades does not function as a pump if air is mixed into the pump chamber 13 and the rotating blades are exposed to the air. For this purpose, a method is usually adopted in which water is poured from a water filling port to fill the pump chamber with water, the water filling port is closed, and then the pump is started. However, in the present invention, although a part of the gas sucked from the gas sampling pipe 2 is branched from the gas branch pipe 3, most of the gas enters the pump chamber of the suction type water pump 6. In the present invention, a water supply pipe is connected to a water filling port of the self-priming water pump 6 in order to prevent the pump from stopping due to gas entering the pump chamber of the self-priming water pump 6. During operation, water is always supplied from the water supply pipe to the water filling port, and the pump chamber is always filled with water so that the gas seal does not break the water seal. The water filling port of the self-priming water pump is normally used to fill the pump chamber with water before starting, and remains closed during operation. However, in the present invention, the water filling port is always used as the water supply port so that the water seal is not broken by the gas mixed into the pump chamber. It is the first time.

In the present invention, the gas branched from the gas branch pipe 3 contains water vapor. If water vapor affects the subsequent analysis, heat the gas to increase the saturated vapor pressure so that the relative humidity decreases, or cool the gas to reduce the saturated vapor pressure, Examples of the method include a method in which water vapor contained in a gas is dewed to reduce the humidity of the gas.

The gas which can be suitably sampled by the present invention is preferably insoluble or hardly soluble in water. For example, gases such as oxygen, nitrogen, and hydrogen can be used.

[0014]

According to the gas sampling method of the present invention, a gas to be sampled is sucked together with water, and a self-priming water pump is used as a driving force for the suction.
According to the present invention, even if dust is contained in the gas to be sampled, the dust does not block the self-priming pump, and gas sampling can be continuously performed for a long period of time.

[0015]

EXAMPLES Examples of the present invention will be shown below, but the present invention is not limited thereto.

Example 1 A combustion gas was sampled using the gas sampling device shown in FIG. Inner tube with inner diameter 9mm, inner diameter 16
Water was supplied at a rate of 5 L / min to an inner tube of a gas sampling tube having a triple tube structure consisting of an outer tube having a diameter of 41 mm and an outermost tube having an inner diameter of 41 mm. The mixture of gas and water is sucked from the outer pipe, and a part of the gas is led to the analyzer through the pipe and the gas branch pipe. On the other hand, a mixture of most of the gas and water enters the pump chamber through the water suction port of the self-priming water pump via a pipe, and is discharged from the water discharge port. Even after three months from the start of the operation, the gas suction amount from the gas sampling tube was 3 L / min, which was the same as at the beginning of the operation.
In addition, gas sampling could be continuously performed without clogging of the gas sampling tube and the suction type water pump.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a gas sampling device of the present invention.

FIG. 2 is a schematic diagram of a conventional gas sampling device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Water supply source 2 Gas sampling pipe 3 Gas branch pipe 4 Ejector 5 Piping 6 Suction type water pump 7 Inner pipe 8 Outer pipe 9 Outer pipe 10 Water suction port 11 Water discharge port 12 Water filling port 13 Pump room

Claims (1)

(57) [Claims] A water supply source, a gas sampling pipe, a gas branch pipe, and a self-priming water pump are connected in this order by piping, and a water supply pipe is connected to a water filling port of the self-priming water pump. A gas sampling method, wherein a sampling device having a pipe connected to a gas branch pipe is used for sampling while supplying water to a water filling port while the self-priming water pump is operating.