JP7569255B2 - Room Pressure Control System - Google Patents

Description

The present invention relates to a room pressure control system for multiple rooms with different degrees of prevention of particulate contamination and microbial contamination in pharmaceutical manufacturing plants, regenerative medicine product factories, regenerative medicine research facilities, animal breeding facilities, etc.

Among the above-mentioned facilities, clean rooms in regenerative medicine facilities, laboratory animal breeding facilities and the like often have a plurality of rooms with different cleanliness classes.
In the clean rooms, a difference in pressure is set between adjacent rooms to prevent air from flowing backwards from a room with a lower cleanliness level to a room with a higher cleanliness level, thereby causing contamination.
FIG. 7 is an example of a duct system diagram of an air conditioning system that uses a differential pressure damper method that has long been used in clean rooms with multiple rooms. An air conditioner 1 equipped with a supply air fan 2 and a return air (exhaust) fan 3 control the room pressure of three air conditioned rooms with different room pressure conditions, Room A (target room pressure 45 Pa), Room B (target room pressure 30 Pa), and Room C (target room pressure 15 Pa), by controlling the supply air volume, exhaust air volume, and flow rate of the differential pressure damper.

The main air supply duct 7 from the air supply fan 2 branches off into air supply ducts 8, 9, 10 leading to rooms A, B, and C respectively, and each air supply duct is connected to a constant air volume device 11, 12, 13, a reheat heater 14, 15, 16, an air volume adjustment damper 17, 18, 19, and an air supply vent 20, 21, 22 equipped with a high-performance filter.
The return air that has been conditioned in rooms A, B, and C flows from intakes 31, 32, and 33, respectively, through return air branch ducts 34, 35, and 36 to join the main return air duct 37.
A differential pressure damper 51 is provided at an opening in the chamber wall surface separating chambers A and B, and a differential pressure damper 52 is provided at an opening in the chamber wall surface separating chambers B and C.

In the above control system, the conditioned air supplied from the air conditioner 1 is distributed to each room at a constant volume by the constant air volume devices 11, 12, and 13, and is supplied to each room from the air supply and ventilator 20, 21, and 22 via air volume adjustment dampers 17, 18, and 19 for fine adjustment of the air volume.

In relation to this type of control, for example, an animal facility has been disclosed in which multiple sealed animal rooms are arranged in parallel, and a clean corridor and a dirty corridor are connected to each animal room by a differential pressure damper so that excess air can flow between the rooms in a prioritized order. The air conditioner's intake fan supplies outside air at a high pressure in the clean corridor and an intermediate pressure to each animal room, and the air flows between the rooms through differential pressure dampers installed on the walls between the rooms, into the dirty corridor, and is exhausted by an exhaust fan, thereby realizing a pressure difference between the rooms (JP Patent Publication No. 2-49687).

In the above facilities, to accommodate sudden fluctuations in room pressure caused by opening and closing doors or turning local exhaust on and off, differential pressure dampers are installed on the walls to absorb momentary fluctuations in differential pressure, which is a simple and effective method of controlling room pressure because it has a simple structure and functions without the need for electronic control.

Special Publication No. 2-49687

However, although a normal differential pressure damper will close in the event of an instantaneous reversal of the differential pressure, there is a risk that air from Room B will flow into Room A, where the pressure is higher, in the opposite direction to the direction that is originally desired for contamination prevention, due to turbulence in the airflow around the opening. When an instantaneous reversal of the differential pressure occurs, the differential pressure damper quickly closes due to pressure, but this may result in the airflow being pushed in the closing direction, which means that some of the air from the lower room pressure side may flow back into the higher room pressure side.
One way to prevent this is to use technology to electronically control room pressure by varying the air volume, but this is costly as it requires a complex system to respond to instantaneous fluctuations in room pressure.
In addition, because the differential pressure damper is a structure that opens into the wall, visible matter such as powder and body hair (in the case of animal breeding) tends to accumulate in the positive pressure side of the chamber, causing problems in cleaning.
Furthermore, from the worker's perspective, the opening and closing action in response to fluctuations in room pressure can be visually unpleasant.
SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to solve the above-mentioned problems of the conventional technology and to provide a room pressure control system that uses a normal differential pressure damper to control a plurality of rooms having different room pressures.

The present inventors have achieved the above object by the following means.
<1> A system for controlling room pressure in a case where a constant supply air volume determined for each of a plurality of air-conditioned rooms having different room pressure conditions is sent to each of the air-conditioned rooms and a positive pressure is formed by reducing the return air volume by a certain amount,
Each room is equipped with an air supply duct, a filtered air supply outlet, and a return air branch duct.
A return air branch duct provided in a room with a high target room pressure and a return air branch duct provided in another room are connected by a pressure adjustment duct on the upstream side where the return air branch duct is connected to a return air main duct for air conditioning return air;
A room pressure control system for multiple rooms, characterized in that when there are three or more rooms with high target room pressures, a differential pressure damper is provided in the pressure adjustment duct so that air flows from the return air branch duct side of the higher pressure room to the return air branch duct side of the lower pressure room, and when there are three or more rooms with high target room pressures, the return air branch duct provided in the room with the highest target room pressure, the return air branch duct provided in the room with the second highest room pressure, the return air branch duct provided in the room with the third highest room pressure, and the return air branch ducts provided in each room thereafter in order of decreasing room pressure are connected by a pressure adjustment duct upstream of the return air main duct for air conditioning return air, and the pressure adjustment ducts are connected upstream of the return air branch duct in order of decreasing average room pressure of the two rooms to be connected .

<2> A system for controlling room pressure in a case where a constant supply air volume determined for each of a plurality of air-conditioned rooms having different room pressure conditions is sent to each of the air-conditioned rooms and a positive pressure is formed by reducing the return air volume by a certain amount,
Each room is equipped with an air supply duct, a filtered air supply outlet, and a return air branch duct.
In order of the rooms with the highest target room pressure, a return air branch duct provided in the room with the highest target room pressure is connected to a return air branch duct provided in the room with the next highest room pressure by a pressure adjustment duct on the upstream side where the return air branch duct is connected to a return air main duct for air conditioning return air;
A room pressure control system for multiple rooms, characterized in that when there are three or more rooms with high target room pressures, a differential pressure damper is provided in the pressure adjustment duct so that air flows from the return air branch duct side of the higher pressure room to the return air branch duct side of the lower pressure room, and when there are three or more rooms with high target room pressures, the return air branch duct provided in the room with the highest target room pressure, the return air branch duct provided in the room with the second highest room pressure, the return air branch duct provided in the room with the third highest room pressure, and the return air branch ducts provided in each room thereafter in order of decreasing room pressure are connected by a pressure adjustment duct upstream of the return air main duct for air conditioning return air, and the pressure adjustment ducts are connected upstream of the return air branch duct in order of decreasing average room pressure of the two rooms to be connected .
<3> A room pressure control system for multiple rooms described in <1> or <2> , characterized in that a chamber is provided in a pressure adjustment duct connected between the return air branch ducts, and a differential pressure damper is provided in the chamber.
<4> A room pressure control system for multiple rooms described in any one of <1> to <3>, characterized in that a volume damper (air volume adjustment damper) that can fine-adjust the air volume is provided on the upstream side of the filter of the air supply vent of the supply air duct and on the upstream side of the pressure adjustment duct of the return air branch duct, thereby enabling fine-adjustment of the room pressure by adjusting the supply air volume and the return air volume.

The room pressure control system for multiple rooms of the present invention provides the following effects.
The configuration involves adding a pressure adjustment duct to the upstream part of the return air duct system in a normal air conditioning system, and simply placing the differential pressure damper, which has traditionally been widely used, in the pressure adjustment duct, thereby reducing costs.
In addition, by providing a differential pressure damper between each return air branch duct between rooms that require a differential pressure, it is possible to maintain an inter-room pressure difference that does not cause contamination within the room.
Furthermore, the opening and closing operation of the differential pressure damper is invisible to the worker, so it does not interfere with the workplace.

Configuration diagram of the clean room pressure control system of the present invention FIG. 1 is a diagram showing an installation state of a differential pressure damper in a room pressure control system for a clean room according to the present invention. A comparison diagram of the differential pressure damper of the prior art and the differential pressure damper of the present invention. FIG. 1 is a diagram showing an embodiment of maintaining the differential pressure order between different rooms by the differential pressure damper of the present invention; A plan view of the differential pressure damper according to the related art maintaining the differential pressure ranking between multiple rooms and a plan view of the differential pressure damper according to the present invention maintaining the differential pressure ranking between multiple rooms A plan view of the differential pressure damper according to the related art maintaining the differential pressure ranking between multiple rooms and a plan view of the differential pressure damper according to the present invention maintaining the differential pressure ranking between multiple rooms Piping diagram of an air conditioning system using a conventional differential pressure damper

An embodiment of a room pressure control system for multiple rooms according to the present invention will be described in comparison with a configuration diagram of a conventional air conditioning system using a differential pressure damper system.
FIG. 1 is a configuration diagram of a clean room pressure control system according to the present invention, and FIG. 2 is a diagram showing an installation state of a differential pressure damper in the clean room pressure control system according to the present invention.
FIG. 3 is a comparative diagram of (A) the maintenance of differential pressure priority among multiple rooms by a conventional differential pressure damper and (B) the maintenance of differential pressure priority among multiple rooms by a differential pressure damper of the present invention. FIG. 4 is a diagram showing an embodiment of the maintenance of differential pressure priority among multiple rooms by a differential pressure damper of the present invention. FIG. 4A shows a case where differential pressures between adjacent rooms B, C, and D are maintained with respect to room A. FIG. 4B shows a case where differential pressures in a cascade are maintained in the order of room A > room B > room C > room D. FIG. 5 shows a case where differential pressure priority among multiple rooms is maintained by a conventional differential pressure damper. FIG. 6A is a plan view of inter-room differential pressure priority maintenance by a differential pressure damper of the present invention, and FIG. 6B is a plan view of inter-room differential pressure priority maintenance by the differential pressure damper of the present invention, in which the differential pressure between room A and adjacent rooms B, C, and D is maintained. FIG. 6A is a plan view of inter-room differential pressure priority maintenance by a conventional differential pressure damper, and FIG. 6B is a plan view of inter-room differential pressure priority maintenance by the differential pressure damper of the present invention, in which the differential pressure is maintained in a cascade order of room A > room B > room C > room D.

In Figures 1 to 6, reference numeral 1 is an air conditioner equipped with a supply air fan 2, 2 is the supply air fan, and 3 is a return air fan. In the case of Figure 1, the air conditioner 1 and the return air fan 3 control the room pressure of three air-conditioned rooms, Room A 4, Room B 5, and Room C 6, which have different room pressure conditions, using a system connected by a main supply air duct, a main return air duct, and partially a return air duct.
Reference numeral 7 denotes a main air supply duct extending from the air supply fan 2, and reference numerals 8, 9, and 10 denote air supply ducts which are connected to room A 4, room B 5, and room C 6, respectively.
Reference numerals 11, 12, and 13 denote fixed air volume devices, 14, 15, and 16 denote reheat heaters, 17, 18, and 19 denote air volume adjustment dampers, and 20, 21, and 22 denote air supply and control ports each equipped with a high-performance filter, which are connected to the air supply ducts 8, 9, and 10, respectively.
Reference numerals 31, 32, and 33 denote intakes provided in room A 4, room B 5, and room C 6, respectively, and 34, 35, and 36 denote return air branch ducts connected to the intakes 31, 32, and 33, respectively. The return air that has been conditioned in room A 4, room B 5, and room C 6 flows from the intakes 31, 32, and 33 through the return air ducts 34, 35, and 36, respectively, to join the main return air duct 37.

41 is a pressure adjustment duct connected to the return air branch ducts 34 and 35, 42 is a pressure adjustment duct connected to the return air branch ducts 35 and 36, 43 is a chamber connected to the pressure adjustment duct 41, and 44 is a chamber connected to the pressure adjustment duct 42. A differential pressure damper 51 is provided in chamber 43, and a differential pressure damper 52 is provided in chamber 44 so that air flows from the return air branch duct side of the high pressure chamber to the return air branch duct side of the low pressure chamber (see Figure 2).

Using the example shown in FIG. 3, the maintenance of the differential pressure priority between two chambers by a conventional differential pressure damper (A) and the maintenance of the differential pressure priority between two chambers by the differential pressure damper of the present invention (B) will be compared and explained.
In the case of maintaining the differential pressure ranking between two chambers using a conventional differential pressure damper in FIG. 1A and the case of maintaining the differential pressure ranking between two chambers using the differential pressure damper of the present invention in FIG. 1B, the chamber pressure of chamber A is set to 30 Pa and the chamber pressure of chamber B is set to 15 Pa, and the chamber pressure of chamber A is set to be greater than the chamber pressure of chamber B.
The air balance (unit: CMH (m ³ /h)) in FIG.

Room A air balance: Input [1] 1000 = Output [2] 850 + [3] 150
Room B air balance: Input [4] 400 + [3] 150 = Output [5] 550

In this way, (1) 1,000 CMH of supply air is supplied to room A, (2) 850 CMH is discharged as return air, and (3) 150 CMH is supplied to room B through the differential pressure damper.

In addition, 400 CMH of supply air [4] is supplied to room B, and together with 150 CMH of air [3] supplied from room A via a differential pressure damper, 550 CMH of air [5] is discharged as return air.
The above is for the steady state, but in this state, when the door on the A side is opened and closed, air escapes through the door, and the pressure in A drops, the pressure difference between A and B becomes smaller and smaller, causing the pressure in A to drop more than that of B, eventually resulting in the reverse. At this time, the differential pressure damper closes quickly in proportion to the smaller pressure difference, and the amount of air flowing from A to B ([3] 150 CMH) decreases.
As a result, the pressure in chamber A increases and the pressure in chamber B decreases. When the door is then closed or the original set pressure difference is reached, the damper opening returns to the original position and the steady state is reached.
If the pressure in room A increases, the opening of the differential pressure damper increases, increasing the outflow air volume from room A ([3] 150 CMH), thereby rebalancing the room pressure difference.

The air balance (unit: CMH (m ³ /h)) in FIG.

Room A air balance: Input [1] 1000 = Output [2] 1000
Room B air balance: Input [4] 400 = Output [2] 400

However, because air moves from the return air duct from room A to the return air duct of room B [3] 150, the return air branch duct system has the same balance as (A) above. Here, the arrow tip of the return air branch duct of the return air system RA intersects with the return air main duct, and the return air flows to the return air fan. Between the return air branch ducts, the pressure adjustment duct is connected in parallel with the return air main duct.

In this way, exactly the same effect as the conventional differential pressure damper method can be obtained.
The exact numerical values differ from those of previous systems because they are due to pressure loss in the suction equipment and duct routes up to the installation of the differential pressure damper, but since the difference is only a few Pa, it is thought that this will not affect the differential pressure ranking (30 Pa > 15 Pa in the figure).

An embodiment of maintaining the differential pressure order among multiple chambers by the differential pressure damper of the present invention will be described with reference to FIG.
The same figure (A) shows the case where the differential pressure between chamber A (chamber pressure 30 Pa) and the adjacent chambers B (chamber pressure 15 Pa), C (chamber pressure 15 Pa), and D (chamber pressure 15 Pa) is maintained, and the return air branch duct connected to chamber A (chamber A RA) is connected to the return air branch duct connected to chamber B (chamber B RA), the return air branch duct connected to chamber C (chamber C RA), and the return air branch duct connected to chamber D (chamber D RA) are each individually connected by pressure adjustment ducts.

Figure 3 (B) shows the case where a pressure difference is maintained in a cascade: Room A (room pressure 45 Pa) > Room B (room pressure 30 Pa) > Room C (room pressure 15 Pa) > Room D (room pressure 0 Pa). The return air branch duct connected to room A (room A RA) and the return air branch duct connected to room B (room B RA) are connected by a pressure regulating duct, the return air branch duct connected to room B (room B RA) and the return air branch duct connected to room C (room C RA) are connected by a pressure regulating duct, and the return air branch duct connected to room C (room C RA) and the return air branch duct connected to room D (room D RA) are connected by a pressure regulating duct, and a pressure difference is created in that order.
Here, when there are three or more chambers with high target room pressures, the return air branch duct (room A RA) provided in the chamber with the highest target room pressure, the return air branch duct (room B RA) provided in the chamber with the second highest room pressure, and the return air branch duct (room C RA) provided in the chamber with the third highest room pressure are connected by pressure regulating ducts upstream of the return air main duct at the end of the arrow, and the pressure regulating ducts are connected upstream of the return air branch ducts in order of highest average room pressure of the two connected chambers.

The difference between maintaining the multi-chamber differential pressure ranking by a conventional differential pressure damper and maintaining the multi-chamber differential pressure ranking by the differential pressure damper of the present invention will be described with reference to Figs.
FIG. 5A is a plan view of a conventional differential pressure damper maintaining a differential pressure priority among multiple chambers, and FIG. 5B is a plan view of a differential pressure damper of the present invention maintaining a differential pressure priority among multiple chambers, where FIG. 5B shows a case in which the differential pressure between chamber A and adjacent chambers B, C, and D is maintained, and FIG. 6A is a plan view of a conventional differential pressure damper maintaining a differential pressure priority among multiple chambers, and FIG. 6B is a plan view of a differential pressure damper of the present invention maintaining a differential pressure priority among multiple chambers, where the differential pressure is maintained in a cascade order of chamber A > chamber B > chamber C > chamber D.

Figure 5 shows a case where room A (room pressure 30 Pa) is adjacent to room B (room pressure 15 Pa), room C (room pressure 15 Pa), and room D (room pressure 15 Pa).The example is made up of a process corridor (room A in the figure) and each manufacturing process room (rooms B to D) in a pharmaceutical manufacturing facility.
FIG. 1A shows a conventional differential pressure damper installed in the partition wall between chamber A and chamber B, which maintains differential pressure priority between chambers.

In the same figure (B), a return air branch duct connected to room A (room A RA), a return air branch duct connected to room B (room B RA), a return air branch duct connected to room C (room C RA), and a return air branch duct connected to room D (room D RA) are each individually connected by pressure regulating ducts.
In the same figure (B), if the pressure in the return air branch duct connected to room A (room A RA) is assumed to be 25 Pa , and the pressure in the return air branch duct connected to room B ( room B RA), the return air branch duct connected to room C (room C RA), and the return air branch duct connected to room D (room D RA) is assumed to be 10 Pa, the differential pressure damper will operate when the pressure reaches 25-10 Pa (differential pressure 15 Pa).

FIG. 6A is a plan view of a conventional differential pressure damper maintaining a differential pressure ranking among multiple chambers, and FIG. 6B is a plan view of a differential pressure damper of the present invention maintaining a differential pressure ranking among multiple chambers, in which the differential pressure is maintained in a cascade order of chamber A > chamber B > chamber C > chamber D.
FIG. 6 shows an example of a regenerative medical product manufacturing facility in which a cell processing room (Room A in the figure: room pressure 45 Pa), an airlock (Room B: room pressure 30 Pa), a dressing room (Room C: room pressure 15 Pa), and a preparation room (Room D: room pressure 5 Pa) are arranged side by side.

In FIG. 1A, a differential pressure damper is installed on the partition surface between each chamber.
In the same figure (B), the return air branch duct connected to room A (room A RA) and the return air branch duct connected to room B (room B RA) are connected by a pressure regulating duct, the return air branch duct connected to room B (room B RA) and the return air branch duct connected to room C (room C RA) are connected by a pressure regulating duct, and the return air branch duct connected to room C (room C RA) and the return air branch duct connected to room D (room D RA) are connected by a pressure regulating duct, and a differential pressure damper is installed in the chamber connected to each duct.

In the same figure (B), if the pressure in the return air branch duct connected to room A (room A RA) is assumed to be 40 Pa, the differential pressure damper will operate at 40-25 Pa. If the pressure in the return air branch duct connected to room B (room B RA) and the return air branch duct connected to room C (room C RA) is assumed to be 25 Pa, the differential pressure damper will operate at 25-10 Pa. If the pressure in the return air branch duct connected to room C (room C RA) and the return air branch duct connected to room D (room D RA) is assumed to be 10 Pa, the differential pressure damper will operate at 10-0 Pa.

In the above explanation, an intake port is provided at the bottom of the room, a return air branch duct is provided at the intake port, and a differential pressure damper is installed between each return air branch duct of rooms with different room pressures, but it is also possible to provide an intake port at the top of the room and a return air branch duct at the intake port. In this case, since the return air branch duct is installed inside the ceiling, the differential pressure damper is also installed inside the ceiling.

Based on the configuration described above, in the room pressure control system of the present invention, even if the differential pressure between the rooms is momentarily disturbed due to the opening and closing of the door to the rooms, the airflow passing through the differential pressure damper in the return air branch duct does not affect the inside of the room, so contamination can be reliably prevented.
In addition, contamination can be reliably prevented even if the room pressure between multiple rooms is momentarily reversed when the air conditioner is started or stopped.

As explained in detail above, the room pressure control system of the present invention can be used in pharmaceutical manufacturing plants that have multiple rooms with different pressure differentials, regenerative medicine product factories, regenerative medicine research facilities, or animal breeding facilities.

REFERENCE SIGNS LIST 1 air conditioner 2 supply air fan 3 return air fan 7 main supply air duct 8, 9, 10 supply air duct 11, 12, 13 constant air volume device 14, 15, 16 reheat heater 17, 18, 19 air volume adjustment damper 20, 21, 22 supply air control port 31, 32, 33 intake port 34, 35, 36 return air branch duct 37 main return air duct 41 42 pressure adjustment duct 43 44 chamber 51 52 differential pressure damper

Claims (4)

A system for controlling room pressure when a constant supply air volume determined for each of a plurality of air-conditioned rooms having different room pressure conditions is sent to each of the air-conditioned rooms and a positive pressure is formed by reducing the return air volume by a certain amount,
Each room is equipped with an air supply duct, a filtered air supply outlet, and a return air branch duct.
A return air branch duct provided in a room with a high target room pressure and a return air branch duct provided in another room are connected by a pressure adjustment duct on the upstream side where the return air branch duct is connected to a return air main duct for air conditioning return air;
A room pressure control system for multiple rooms, characterized in that when there are three or more rooms with high target room pressures, a differential pressure damper is provided in the pressure adjustment duct so that air flows from the return air branch duct side of the higher pressure room to the return air branch duct side of the lower pressure room, and when there are three or more rooms with high target room pressures, the return air branch duct provided in the room with the highest target room pressure, the return air branch duct provided in the room with the second highest room pressure, the return air branch duct provided in the room with the third highest room pressure, and the return air branch ducts provided in each room thereafter in order of decreasing room pressure are connected by a pressure adjustment duct upstream of the return air main duct for air conditioning return air, and the pressure adjustment ducts are connected upstream of the return air branch duct in order of decreasing average room pressure of the two rooms to be connected . A system for controlling room pressure when a constant supply air volume determined for each of a plurality of air-conditioned rooms having different room pressure conditions is sent to each of the air-conditioned rooms and a positive pressure is formed by reducing the return air volume by a certain amount,
Each room is equipped with an air supply duct, a filtered air supply outlet, and a return air branch duct.
In order of the rooms with the highest target room pressure, a return air branch duct provided in the room with the highest target room pressure is connected to a return air branch duct provided in the room with the next highest room pressure by a pressure adjustment duct on the upstream side where the return air branch duct is connected to a return air main duct for air conditioning return air;
A room pressure control system for multiple rooms, characterized in that when there are three or more rooms with high target room pressures, a differential pressure damper is provided in the pressure adjustment duct so that air flows from the return air branch duct side of the higher pressure room to the return air branch duct side of the lower pressure room, and when there are three or more rooms with high target room pressures, the return air branch duct provided in the room with the highest target room pressure, the return air branch duct provided in the room with the second highest room pressure, the return air branch duct provided in the room with the third highest room pressure, and the return air branch ducts provided in each room thereafter in order of decreasing room pressure are connected by a pressure adjustment duct upstream of the return air main duct for air conditioning return air, and the pressure adjustment ducts are connected upstream of the return air branch duct in order of decreasing average room pressure of the two rooms to be connected . The room pressure control system for multiple rooms described in claim 1 or 2, characterized in that a chamber is provided in the pressure adjustment duct connected between the return air branch ducts, and a differential pressure damper is provided in the chamber. A room pressure control system for multiple rooms as described in any one of claims 1 to 3, characterized in that a volume damper (air volume adjustment damper) capable of finely adjusting the air volume is provided upstream of the filter of the air supply duct's air supply outlet and upstream of the pressure adjustment duct of the return air branch duct, and room pressure can be finely adjusted by adjusting the supply air volume and the return air volume.

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