JPS5822693B2 - Collection device for mist samples in exhaust gas containing dust - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for collecting a mist sample in exhaust gas containing dust.

At the source, many wet dust collectors and hazardous gas treatment equipment are used to prevent air pollution.

However, the exhaust gas discharged into the atmosphere from these devices contains mist (usually fine liquid particles having a particle size of 1 to several tens of micrometers) containing moisture, cleaning liquid, absorbing liquid, and the like.

When measuring the mist concentration of such exhaust gas, a mist sample is collected using a filter material or the like.

Dust (solid particles) usually coexists in exhaust gas in addition to mist, so when collecting a mist sample, dust is also collected at the same time.

For this reason, the filter material is likely to become clogged or damaged, and the collected mist may leach into the filter material and flow outside.

These are the main causes of reducing measurement accuracy or making measurement difficult or impossible.

The present invention prevents various obstacles to sample collection due to mist when collecting a mist sample from exhaust gas containing dust, and also separates and collects coexisting dust as much as possible, thereby improving not only the mist concentration but also the mist concentration. This also makes it possible to measure dust concentration.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

The figure shows an embodiment of the apparatus for collecting a mist sample in exhaust gas according to the present invention.

In the figure, reference numeral 1 denotes a bag-like filter storage tube, which has an opening 2 at its front end and a reservoir opening 3 at its rear end for connection to the suction side of a suction pump (not shown).

4 indicates the hollow lid member, and the storage tube 1
It is removably fitted into the front end opening 2 of the holder so as to maintain airtightness.

That is, a conical part 5 is formed in the front part of the lid member 4, and its outer circumferential surface can be brought into close contact with the inner circumferential surface of the opening 2 of the storage tube 1 by a rubbing structure, so that airtightness is maintained.

A cylindrical body 6 is formed at the rear end of the lid member 4, and a bag-shaped filter 7 is attached and fixed thereto by a tightening band 14.

An exhaust gas introduction nozzle 8 is inserted into the conical portion 5 substantially along its central axis, and the tip of the nozzle 8 is constricted to form an injection port 9.

On the other hand, a tube body 10 is provided at the center of the rear end of the lid member 4 so as to be substantially coaxial with the cylinder body 6, that is, substantially coaxially with the nozzle 8.

One end of the tubular body 10 is open 9 toward the inside of the bag-shaped filter 7, and the other end faces the injection port 9 of the nozzle 8.

A collision plate 11 is disposed at the other end of the tube body 10, that is, in front of the injection port 9, and a vent hole 12 through which the sucked gas passes is provided in the wall surface of the tube body behind the collision plate 11.

Reference numeral 13 denotes a holding plate provided to prevent the bag-like filter 7 from coming off from the cylindrical portion 6 of the lid member 4 during use, and is biased by a spring or the like.

Next, the operation of the above-mentioned shingle collection device will be explained.

The exhaust gas is sucked by operating a suction pump (not shown), passes through a nozzle 8, and is injected from an injection port 9 as shown by an arrow.

The inner diameter of the injection port 9 is normally about 21nrIL, and the sucked exhaust gas collides with the collision plate 11 at high speed from here.

At this time, dust and mist in the exhaust gas are separated from the gas flow and collected on the collision plate 11 based on the principle of inertial collision.

The dust and mist collected here depend on the flow rate of the suction and exhaust gases, but at a flow rate of 104/rrlin, particles with a particle size of about 0.8 μm or more are collected.

Therefore, almost all of the mist is collected here, while the coexisting dust is usually smaller in particle size than the mist.
Most are not collected.

Mi was captured. The dust and a small part of the dust are removed from the collision plate 11.
It flows down along the conical part 5 and is accumulated in the conical part 5, and does not flow out to the outside.

On the other hand, the dust and a small portion of the mist that are not collected by the collision plate 11 are introduced into the bag-shaped filter 7 from the opening of the tube body 10 through the ventilation hole 12 as shown by the arrow, where all Too many people are arrested.

It is preferable to use a fluororesin type bag-shaped filter 7 with a collection rate of 99% or more.

Note that the small amount of mist collected in the bag-shaped filter is extremely small, so it will not leak out through the bag-shaped filter, but even if that happens, the storage pipe 1 Since it accumulates inside, it does not leak outside.

As described above, according to the present invention, most of the mist in the exhaust gas is collected by the collision plate, and there is no interference from the mist to the bag-shaped filter, and the separation and collection of mist and dust samples can be carried out smoothly, and measurement accuracy can be improved. It also improves.

Also, regardless of whether the collection device is installed horizontally or vertically,
One of its basic features is that it has a structure that prevents the collected mist from leaking outside.

[Brief explanation of drawings]

The figure is a side sectional view of a mist collection device according to the present invention. In the figure, 1... bag-shaped filter storage tube, 4...
・・One piece member, γ・・・・Bag filter, 8・・
...Exhaust gas introduction nozzle, 11...Collision plate,
14...Tightening band.

Claims (1)

[Claims] 1. A bag-shaped filter storage tube having an opening at the front end and an opening connected to the suction side of the suction pump at the rear end, and a bag-shaped filter that is removably fitted into the front end opening of the bag-shaped filter storage tube. an exhaust gas introduction nozzle is inserted into the lid from the center of the front end of the lid, and its tip is narrowed to form an injection port;
A tube body is inserted from the center of the rear end of the lid member so as to face the nozzle injection port, and a collision plate is disposed at the tip of the tube body, and a wall surface of the tube body behind the tube body is provided with a collision plate. A device for collecting a mist sample in exhaust gas containing dust, characterized by having pores.