JPS61295445A - Ventilating and air-conditioning device in atomic power plant - Google Patents

Abstract

PURPOSE:To prevent the surface of a filter from adhesion of snow, which invades from an atmosphere intake port, by a method wherein a pre-filter for collecting the snow and removing it from atmosphere is provided between the atmosphere intake port and the former filter. CONSTITUTION:A louver 2, having a structure which makes invasion of snow difficult, is mounted at the atmosphere intake port 1a and a punching plate 21, which serves as the pre-filter, and an infrared rays heater 22, for heating the punching plate 21, are arranged in a space 20. According to this method, invasion of snow and particles is reduced remarkably and invaded small amount of snow and particles may be removed by melting or stall while atmosphere passes through the punching plate 21. Accordingly, clogging of the surface of bag type filter 4 due to adhesion of snow or particles, especially snow, may be prevented effectively. On the other hand, the punching plate 21 has also flow regulating effect of air stream at the inlet side of the bag type filter 4, therefore, the provision thereof is also effective in seasons except snow falling season.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a ventilation air conditioning system that controls temperature and humidity in each room of an atomic coupler plant and maintains cleanliness. The present invention relates to a ventilation air conditioning system for an atomic coupler that can prevent malfunctions caused by.

(Technical Background of the Invention) The ventilation air conditioning system in Atomic Kaburan maintains the environment necessary for the normal operation of each key of the plant, and also maintains the appropriate environmental conditions for operators and workers (indoor temperature, humidity,
cleanliness, ventilation flow, etc.).

Figures 14 to 16 show this type of conventional ventilation air conditioner, in which a louver 2 is attached to an outside air intake port 1a provided in a building 1, and a louver 2 is installed to draw outside air into the supply air processing device 3. , preventing rainwater from entering the building 1.

Inside the supply air processing device 3, a bug-type filter 4 for removing foreign matter such as dust and particulate salt from the outside air, and a heating coil 5 and a cooling coil 6 for controlling the temperature of the outside air are installed, respectively. The outside air after being processed by the supply air processing device 3 passes through the supply air duct 7 on the right side of the damper 7a.
50% capacity 3 units (one of which has a defect) or 100%00
% capacity 21 units 1 (reserve) JM I 8 allows air to be supplied to each air-conditioned space 9 in spaces with high radiation levels (so-called contaminated areas) or spaces where radioactive materials do not exist (so-called clean areas). ing.

By the way, in the case of air conditioning for contaminated areas, the purpose is to prevent radioactive materials from stagnation in the air conditioned space 9, so as shown in FIG. 14, the air supply duct 7 is
The same volume of air as that supplied to the air conditioned space 9,
Bug type filter 10a and high performance particle filter 1
Exhaust duct 11 equipped with exhaust treatment device 10 having 0b
A one-time type is adopted in which the air is discharged outdoors from the exhaust pipe 13 via the blower 12. The exhaust treatment device 10
Similarly to the blower 8, the blower ta12 has a 50% capacity ff in order to ensure plant safety, reliability, and redundancy.
13 units (one of which is a spare) or 100%00% capacity2
One unit is a spare).

On the other hand, in the case of air conditioning for clean areas, the accumulation of radioactive materials is not a problem, so a part of the air that has been heat exchanged in the air conditioned space 9 is returned to the supply air processing device 3, and the remaining air is A return duct for exhaust air] is adopted.

[Problems with background technology]

In the conventional atomic couplant ventilation air conditioner having the above configuration, foreign objects (birds,
To prevent the intrusion of bird feathers, etc., the length of the − side is 10.
It is customary to arrange a wire mesh called a bird screen with a wire diameter of 1.5 to 2.3 φ.

However, if an atomic couplant is constructed in an area where snowfall changes frequently, snow may adhere to the blades of the bird screen or louver 2 in the case of falling snow with a high moisture content ω.
There is a risk that it will freeze and narrow the air flow path, making it impossible to take in the required amount of air necessary for building ventilation.

On the other hand, in the case of powder snow with a low moisture content, the snow passes through the bird screen and the louver 2 and enters the air supply processing device 3 along with the outside air, and is deposited and collected on the bug-type filter 4, especially at the top. If there is a large amount of air, the bug-type filter 4 may become clogged in an extremely short period of time, and the health of the ventilation air conditioning system may not be maintained.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a ventilation air conditioning system that can effectively prevent snow entering from an outside air intake port from adhering to a filter surface.

[Summary of the invention]

The present invention is an atomic coupler in which outside air taken in from an outside air intake port is guided to a filter to remove foreign matter in the outside air, and the outside air after foreign matter is removed is passed through a temperature controller to adjust the temperature and send the air to an air-conditioned space. In ventilation air conditioners, a pre-filter is installed between the outside air intake and the filter to capture snow and remove it from the outside air, so that even if snow gets in, it will not stick to the filter surface. Features.

[Embodiment of the Invention] An embodiment of the present invention will be described below with reference to FIGS. 1 to 12.

In FIG. 1, reference numeral 1 indicates a building, and a louver 2 is attached to an outside air intake port 1a provided in this building 1, which allows outside air to enter the supply air processing device 3 and allows rainwater to enter the building 1. It prevents you from doing so.

As shown in Fig. 1, the louver 2 has its upper end tilted toward the outdoor side by a predetermined angle so that each blade faces vertically downward. The suction surface near the louver 2 has an inclination, so that the contact surface with snow and particles falling from the sky can be reduced.

As shown in FIG. 1, the supply air processing device 3 includes a bug-type filter 4 for removing foreign matter such as dust and particulate salt from the outside air, and a heating coil 5 for controlling the temperature of the outside air.
Cooling coils 6 are respectively installed, and the outside air after being processed by the supply air processing device 3 passes through a supply air duct 7 having a damper 7a, and is sent to each air-conditioned space in a contaminated area or a clean area by a supply lIa machine 8. (not shown).

Space 20 between the louver 2 and the bag type filter 4
Inside, as shown in FIG. 1, a punching plate 21 and an infrared heater 22 for heating the punching plate 21 are arranged.

As shown in FIGS. 2 and 3, the punching plate 21 is made by punching a large number of holes 21a of about 5φM in a rigid plate material such as an aluminum plate, a stainless steel plate, or a hot-dip galvanized steel plate that is resistant to rust and can withstand high temperatures. It is manufactured by bending and forming the trapezoidal waveform into a trapezoidal waveform, which is designed to have a sufficiently low pressure loss and a high snow protection effect. As shown in FIG. 4, this punching plate 21 is vertically installed in the space 20 via a mounting member 23.

A plurality of the infrared heaters 22 are arranged at the upstream side of the punching plate 21 together with the heater cover 24 so that the punching plate 21 can be heated by radiated heat of infrared rays. As shown, the position is fixed via a mounting member 25.

Next, the operation of this embodiment will be explained.

When the supply air processing device 3 is activated during snowfall, the outside air flows through the louver 2.
The air is guided into the space 20 through the bag-type filter 4 to remove foreign matter in the outside air, and then heated by the heating coil 5 and sent to the air-conditioned space (not shown). At the entrance 1a, as shown in Fig. 1, there is a louver 2 whose upper end is tilted toward the outdoor side so that the blade faces vertically downward.
are arranged, the intrusion of snow into the space 20 can be significantly reduced.

In other words, the effect of reducing snow intrusion ω when the two louver surfaces are tilted by 0 degrees is qualitatively considered to be as shown below.

[Calculating the amount of snow that enters from the louver]

A speed ring exists near the louver suction port, and snow and particles falling at a certain speed are caught in the speed ring and sucked into the louver. Therefore, when the suction speed of the louver is high, snow particles that are light and falling at a low speed are sucked into the louver in a large amount. Snow and particles that enter the louver are sucked in when they approach a ring with a velocity greater than their falling velocity.
By setting the speed ring near the louver, it is possible to calculate the snow intrusion m per unit time sucked into the louver.

The velocity ring near the louver is a turbulent flow and the louver shape is three-dimensional, so the equation of motion of the fluid (NaVier-3
It is difficult to solve the equation (tOkO3') strictly using words. Therefore, here, we will give an overview by expanding the two-dimensional model.

As shown in the elevational view and cross-sectional view of FIGS. 5 and 6,
When the suction opening is regarded as a straight line, the virtual constant velocity surface line can be calculated using the following formula.

Q=AO-V =A-V.

C However, Q: Exhaust flow m L: Length of the suction port Ao-Vo: Louver opening area and passing speed A -V: Total surface area of constant velocity surface J: C and passing speed Modifying equation (1), 3 Dimensionally, Figures 7 to 9
As shown in the figure, the constant velocity surface can be approximated to the surface of an ellipsoid.

The equation of the ellipsoid surface shown in FIGS. 7 to 9 is as follows.

2y2z2 From formula (1), 2π-2a-VC(Z) ax (Z)= −〒♂−xr (Z
) ・・・・・・・・・・・・
......(6) Substituting equations (3) to (6) into equation (2), on the other hand, the falling speed of snow particles is V, (m/s), and the snowfall m is H (G/S- ), and the density of snow particles in the air is ρ(g
/TIt], the following formula holds true.

(m/s) C9/foot) (Q/S-foot) v,
X ρ −H ・・・・・・・・・(8) Actually, in equation (8), V1ρ is determined depending on natural conditions and varies, but here, its representative value (average value) is used. and constant.

Snow and particles with a falling speed of 5 are sucked in by y~2 in FIG. 10 and enter the louver by 1'. Therefore, the amount of snow that enters the louver is expressed by the following formula.

When the louver mounting surface is inclined, the area of the constant velocity surface (the surface of the inner body of the louver) through which snow and particles enter can be determined from FIG. Therefore, the snow fullG(θ) entering the louver at that time is G(θ)-8' (Z)XV,
Xρ From equations (10) and (11), -1-10π (12) The relationship between equation (12) is shown in FIG. If the angle of the louver mounting cylinder is 30 degrees, it is possible to prevent snow intrusion by 33% from FIG. 11.

For reference, the exhaust flow ff1Q is based on equation (10).

FIG. 12 shows a graph regarding snow intrusion IG using snow falling speed vS as a parameter.

As is clear from Fig. 12, snow intrusion ff1G is Q
It is proportional to the square of v8 and inversely proportional to the square of v8. Therefore, in order to reduce snow intrusion mG, the important parameters are to reduce Q and increase ■8.

In this way, with the louver 2 tilted at θ=30°, θ=
Although it can reduce the amount of snow intrusion by about 33% compared to the conventional specification of 0゛, it cannot completely prevent snow intrusion. Therefore, the snow and particles that cannot be removed will enter the space 20 together with the outside air.

However, a punching plate 21 having a large number of holes 21a is disposed in the space 20, and this punching plate 21 is heated by an infrared heater 22, so that the snow that has entered with the outside air will not penetrate the punching plate 21. Most of the particles that are melted and removed while passing through the punching plate 21 are decelerated and stalled when they collide with the punching plate 21, and are dropped and removed by their own weight.

By the way, since the infrared heater 22 heats the punching plate 21 by radiating infrared heat, other general heating methods (heating by hot air, gas lamp, sheathed heater, etc.) can be used.
It has advantages such as shorter heat-up time, less influence by airflow, and compactness.

Further, although the infrared heater 22 has a sufficiently long life, its replacement is extremely easy as it is the same as the replacement method of a general fluorescent lamp.

In addition, atomic couplers are generally installed in coastal areas, and equipment installed outdoors is subject to severe salt damage. If you install it just before the end of the season, you can extend its life even further.

Next, the required logarithm of the infrared heater 22 will be considered.

The amount of snowfall varies greatly depending on the region, but here we assume a region with extremely heavy snowfall and consider the following conditions.

[Conditions] At a snowfall rate of 1cIR/h, the amount corresponding to 1TIt per sec is 0.28g, assuming the specific gravity of snow to be 0.1.

(100X100XIX0.1/3600) If the falling speed of snow is 1TrL/SeC, then 0.28g of snow is contained in the air at 11d.

Since the correlation between snowfall m and snowfall m is unknown, calculations are made under the above conditions.

[Removal, etc.]

As an example, at the 1.1 million W nuclear power plant, the most
As an example of a system with a large supply air M, consider a facility with a capacity of 500,000 rd/h.

500.000 boxes xo, 28=14ON9...
(13) The energy required to turn ice at 0℃ into water at 0℃ is 80
Cal/g 3, 1 to cal/5ecx 4, 2 J/cat
=13 KJ/5ec= W to 13
-・= (15) From the above, ff150 for air supply
The amount of heating required by the infrared heater 22 for an air supply device of 10,000 Td/h is 13 W.

The required number of infrared heaters is determined by taking into account heater efficiency and heat transfer loss due to airflow in contact with the punching plate 21 in order to obtain the above-mentioned required heating amount.

In this way, the outside air intake port 1a is equipped with the louver 2 with a structure that prevents snow from entering, and the punching plate 21 and the infrared heater 22 for heating it are arranged in the space 20, so that snow and particles are prevented from entering. Intrusion can be greatly reduced, and the nine minutes of snow and particles that have entered can be removed by melting or stalling while the outside air passes through the punching plate 21. Therefore, it is possible to effectively prevent snow or particles, especially snow, from adhering to the surface of the bag-type filter 4 and causing clogging.

Furthermore, since the punching plate 21 also has the effect of rectifying the airflow on the side of the four bag-type filters, its installation is effective even at times other than snowfall.

In addition, since the infrared heater 22 is used to heat the punching plate 21, the heat-up time is extremely short, and the operator can turn on the light only when necessary at his/her discretion, reducing the burden on the operator and running costs. can be suppressed.

FIG. 13 shows another embodiment of the present invention, in which the structure of the punching plate 21 side is changed.

That is, as shown in FIG. 13, the outside air intake port 1a of the building 1 is provided to be offset downward with respect to the supply air processing device 3, and the outside air taken in from this outside air intake port 1a is first 30, and is then guided to the space 20 of the air supply processing device 3 via a bird screen 31 arranged on the top surface 30a.

The lower chamber 30 has an outside air intake port 1a as shown in FIG.
The surface 30b facing the bird screen 31 is formed on a slope with the upper end facing toward the indoor side, and the bird screen 31 has a surface 30b facing the top surface 30.
It is installed at a position closer to the outdoor side than the connecting portion with the facing surface 30b of the portion a.

As a result, the opposing surface 30b and the portion of the top surface 30a from the end of the bird screen 31 to the connecting portion with the opposing surface 30b constitute an interference plate 32 having a V-shaped cross section.

4 [Other parts have the same configuration as the previous embodiment.

Next, the operation of this embodiment will be explained.

When the air supply processing device 3 is activated during snowfall, snow is taken into the building 1 through the outside air intake port 1a along with the outside air. This outside air accompanied by snow flows upward in the lower chamber 30 after passing through the outside air intake port 1a, but at this time, the snow hits and adheres to the interference plate 32 due to inertial force, and most of the snow is deposited here. removed. Snow attached to the interference plate 32 is removed from the inclined opposing surface 30.
b and is discharged outdoors from the outside air intake port 1a.

The outside air from which most of the snow has been removed by flowing upward inside the royal house 30 is guided into the space 20 through the bird screen 31, but at this time, some of the snow in the outside air is
It adheres to the bird screen 31 and is removed.

The outside air introduced into the space 20 through the bird screen 31 is bent in an L shape within the space 20 and then introduced to the punching plate 21, but at this time, some of the snow is sieved off. The remaining snow is removed from the outside air by the punching plate 21.

The snow melted and removed by the punching plate 21 is
It becomes snowmelt water that flows on the floor surface of the space 20 and flows down from the bird screen 31 to the upper elevation 30, but at this time,
The snow on the floor of the space 20 and the snow adhering to the bird screen 31 is melted by the snow melting water, and the snow adhering to the bird screen 31 is melted by the snow melting water,
The water is drained outdoors from the outside air intake port 1a along with the snow that had arrived on the 2nd floor.

Even with this configuration, the amount of snow that enters into the space 20 is reduced, and the snow that enters into the space 20 is removed by the punching plate 21, so that the same effects as in the embodiment described above can be obtained. .

Furthermore, in this embodiment, since there is no need to provide the louver 2 at the outside air intake port 1a, the outside air intake port 1a can be made smaller. That is, when arranging the louver 2, it is customary to consider the aperture reduction rate of the outside air intake port 1a by about 40%, but in this embodiment, only the bird screen 31 needs to be considered, so the aperture reduction rate It is sufficient to consider about 10%. Therefore, compared to the case where the louver 2 is provided, the outside air intake port 1a
The opening area can be reduced by about 30%.

In both of the above embodiments, the punching plate 21 is heated by the infrared heater 22. However, in areas where snowfall is not so heavy, the infrared heater 22 may be omitted and the collision effect of the punching plate 21 alone can be avoided. The desired effect can also be expected. Similarly, even if the structure of the outside air intake port 1a is the same as the conventional structure, sufficient effects can be obtained by the punching plate 21.

Further, in both of the above embodiments, the punching plate 21 is used as a pre-filter installed in the space 20, but the same effect can be obtained even if a rough filter is used instead.

〔Effect of the invention〕

As explained above, the present invention includes a pre-filter that captures snow and removes it from the outside air between the outside air intake port and the filter, thereby preventing snow from adhering to the filter surface. The functions of the ventilation air conditioning system can be maintained in a healthy manner.

[Brief explanation of the drawing]

Fig. 1 is a configuration diagram showing an embodiment of the present invention, Fig. 2 is a front view of the punching plate, Fig. 3 is a plan view thereof, Fig. 4 is a detailed view of the main part of Fig. 1, and Fig. 5 is a An elevational view of a virtual constant velocity surface line when the suction opening is regarded as a straight line, Figure 6 is a cross-sectional view of the same,
Fig. 7 is a schematic diagram of uniform velocity distribution at the louver suction port, Fig. 8 is its X-Z plan view, Fig. 9 is its y-z plan view, and Fig. 10 is the uniform velocity distribution when the louver suction surface is inclined. Figure 11 is a graph showing the relationship between snow penetration level and louver slope;
The figure is a graph showing the relationship between snow penetration depth, flow rate, and snow falling speed, and Figure 13 is a diagram equivalent to Figure 1 showing another embodiment of the present invention.
Fig. 14 is a system diagram showing a conventional ventilation air conditioner, Fig. 15 is a perspective view of the atomic couplant showing the louver installation position,
FIG. 16 is an enlarged sectional view taken along the line x vi -X Vl in FIG. 15. 1... Building, 1a... Outside air intake, 2... Louver, 3... Air supply, processing device, 4... Bug type filter, 5... Heating coil, 6... Cooling Coil, 9...
・Air conditioned space, 20... Space, 21... Punching plate, 21a... Hole, 22... Infrared heater, 3
0... Lower chamber, 30a... Top surface, 30b... Opposing surface, 31... Bird screen, 32... Interference plate. Applicant's agent Kiyoshi Inomata Figure 2 Figure 312i Figure 7 Figure 1o Figure 11 b5 2 L77/77 stone cough: vs
(---) Figure 12 0a Figure 14 Figure 150

Claims (1)

[Scope of Claims] 1. Outside air taken in from the outside air intake port is guided to a filter to remove foreign matter from the outside air, and the outside air after foreign matter is removed is passed through a temperature controller to adjust its temperature and is then sent to the air-conditioned space. A ventilation air conditioning system for a nuclear power plant, characterized in that a pre-filter is provided between the outside air intake port and the filter to capture snow and remove it from the outside air. 2. The ventilation air conditioner for a nuclear power plant according to claim 1, wherein a punching plate or a rough filter having a large number of pores is used as the pre-filter. 3. The ventilation air conditioner for a nuclear power plant according to claim 1 or 2, wherein the pre-filter has heating means for melting captured snow. 4. The ventilation air conditioner for a nuclear power plant according to claim 3, wherein the heating means is an infrared heater. 5. Claims 1, 2, 3, or 4, characterized in that a louver whose upper end is tilted toward the outdoor side so that the blade faces vertically downward is attached to the outside air intake port. Ventilation and air conditioning equipment in nuclear power plants as described in Section 1. 6. Claim 1, characterized in that the outside air intake port is deviated downward with respect to the filter, so that the outside air taken in from the outside air intake port is bent and guided to the filter.
A ventilation air conditioning system in a nuclear power plant according to paragraph 2, paragraph 3, or paragraph 4.