EP0667495B1 - Laboratory air feed and exhaust device - Google Patents

Abstract

The system has air consumers (1,3) which are all provided with a built-in air extraction regulator (2,6) and are adjusted to more or less the same pressure drop. The air consumers are connected to a single common air extraction channel (12) which forms the air extraction facility. A ventilation controller (8), to which are communicated the actual values of air extraction mix of the consumers, forms from them a regulated quantity for controlling the inlet air regulator (17) of the inlet air gallery (16).

Description

The invention relates to a laboratory ventilation system for a laboratory that has multiple air consumers including at least one deduction after which Generic term of patent claim 1.

In such a known from WO-A-92/08082 Laboratory ventilation system is the pressure loss of the Laboratory with the help of regulators to a constant Value regulated.

Laboratories generally use a large number of air consumers, which are fume cupboards that are manufactured in various widths and depths and in various designs, in particular for special applications in schools, for digestion work, biochemical work and isotope work. A large number of different fume cupboards are therefore available on the market, the suction air volumes of which range from 300-2000 m ³ per hour, the pressure losses fluctuating between 20 and 1000 pascals. In addition to the fume cupboards, open extraction units, source extraction systems and storage cabinets with extraction systems for all kinds of chemicals are used as air consumers. There are also under-floor extraction systems, ventilated substructures and ventilated cupboards. Finally, in some laboratories, floor suction systems or ceiling suction systems are also used, whereby some of these suction systems run continuously while others are switched on as required.

The supply air required for room ventilation must be draft-free are supplied, also the room air conditioning and keeping the room temperature constant have to. Especially in the summer with buildings with large glass surfaces due to the devices built into the laboratories as well as a high cooling load from the sun. If only a few deductions are provided to determine these cooling loads in the In summer the necessary supply air volume, while in the colder months the necessary supply air quantities are rather determined by the fume cupboards become.

The laboratory ventilation and ventilation systems previously used in practice represent complicated systems that in particular in laboratories with elaborate equipment it can hardly be overlooked are.

2 of the accompanying drawing is a conventional laboratory ventilation system shown, which with an exhaust air line 31 for Aspirating ventilated cabinets 32, an exhaust air duct 33 for Extracting fume cupboards 34 and an exhaust air duct 35 for others Suction is provided. The supply air is via a supply air duct 36 supplied from adjacent rooms and there is room air 37 pushed because there is always a negative pressure in the laboratory must rule.

In the example of a conventional one shown in FIG. 2 Laboratory ventilation systems are therefore three different exhaust air lines 31, 33, 35 and a supply air duct 36 in the room.

Given the wide spread of pressure drops, it happens moreover, that for fume cupboards with two different exhaust systems must be driven, since with large deductions Line pressures are not sufficient. This is then complicated Pipe guides necessary, which in turn increase the room heights and therefore increase the cubature of the building and the investment costs drive up.

The object underlying the invention is therefore in it, a laboratory ventilation system to create that simply built is and in which the exhaust air and supply air lines in a central Exhaust and supply air systems are integrated. By the invention Training should include investment needs, space requirements and operating costs be reduced.

This object is achieved according to the invention through training solved, which is specified in claim 1.

In the training according to the invention is therefore only a single exhaust duct is provided, which works with all consumers is connected, and supply air and exhaust air are controlled via a central Ventilation controller regulated, on which all exhaust air volume values of the consumer and accordingly the manipulated variable for the Supply air control device delivers. Such a laboratory ventilation system is simple and flexible to set up, both at Retrofits as well as conversions and rescheduling.

Particularly preferred refinements and developments the laboratory ventilation system according to the invention are the subject of claims 2 to 7.

If especially the main consumers, namely the deductions automatically when not in use in a state of minimal energy consumption or minimum exhaust air volume is switched it is possible for the entire exhaust air and supply air system to 50% of the to design the necessary peak capacity by using the Ventilation controller also reduces the incoming air becomes. This contributes significantly to a reduction in investment requirements of space requirements and operating costs.

Furthermore, it is when using the invention Laboratory ventilation system possible, the previously necessary Floor height of, for example, 4 m, for example 3.5 m be reduced since only a single air duct can be provided got to.

Fig. 1 eine schematische Darstellung des Ausführungsbeispiels der erfindungsgemäßen Laborbe- und -entlüftungsanlage und

Fig. 2 eine schematische Darstellung einer herkömmlichen Laborbe- und -entlüftungsanlage.

A particularly preferred exemplary embodiment of the invention is described in more detail below with reference to the accompanying drawing. Show it

Fig. 1 is a schematic representation of the embodiment of the laboratory ventilation system according to the invention and

Fig. 2 is a schematic representation of a conventional laboratory ventilation system.

In the laboratory ventilation system shown in Fig. 1 are all exhaust air extraction points on a common exhaust system connected. The suction points that work all the time such as the cupboards 1 for storing chemicals or the base cabinets, medicine cabinets, drying cabinets and the like have mechanically fixed air volume flow controllers or flaps 2, which regulates firmly are. These are facilities that help a spring construction, the volume flow regardless of the form keep constant.

The deductions 3 as larger consumers are with a control system 5, 6 equipped that built into the fume cupboards, and is also formed in the following manner. On every trigger a motion detector is provided so that the sliding window the trigger automatically goes down and one for it Operation provides the necessary minimum volume flow, if nobody works on the trigger for a certain period of time.

All controllers 6 use a data line 7 volume flows currently used, i.e. the actual exhaust air values a central ventilation controller namely a room controller 8. All values of, for example, are still on the room controller 8 on the flaps 2 of the cabinets 1 set constantly Volume flows. The room controller 8 forms from the adjacent ones Values a manipulated variable, which via a data line 9 as a control signal is due to the building management system, a flap 17 in Supply air line 16 is controlled so that the laboratory space in the supply air-exhaust air balance is held. The room controller 8 can the flap 17th also operate directly.

The room is operated at a constant negative pressure, so that a volume flow 18 from the adjacent rooms into the laboratory flows.

If in addition room suction 20 of the ceiling or floor suction 21 are provided and connected, then these are regulated via fixed volume flow controllers 19 and 22, which are lockable and from the sliding window regulator 6 Deductions are controlled. Also the settings of these consumers are at room controller 8.

All consumers are on a single exhaust air line 12 connected, which is possible because they all on the approximately the same pressure loss are set.

The laboratory ventilation system shown in Fig. 1 works in the following way:

The data lying on the room controller 8 via the data line 7 via the fixed or variable at consumers 1, 3 regulated exhaust air volumes are converted into a corresponding manipulated variable converted to adjust the flap 17 of the supply air line 16, such that for a corresponding to the required amounts of exhaust air Air supply is ensured.

If a user wants to work on trigger 3, then he can raise the trigger's sliding window which means that the controller 6 of the fume cupboard starts up the volume flow of the fume cupboard and thereby enables safe work on the fume cupboard. The corresponding one Data for the changed exhaust air volumes are available on Room controller 8. When the user leaves the fume hood, it will registered by a motion detector 4 on the trigger 3, whereupon the sliding window closes automatically. After closing the Sliding window regulates the controller 6 via the control flap 5 Volume flow back down to the minimum.

The air values of all fixed values are thus on the room controller 8 Aspirations as well as via bus or analog lines from all controllers the currently used volume flows, i.e. the Actual values of the exhaust air quantities. The controller 8 adds these values and sends a corresponding bus or analog signal to the room building control center further. This regulates the supply air line 16 in such a way that via the flap 17, the room supply air of the required amount of exhaust air is adjusted. There remains a small amount of residual air 18, which is drawn in through corridor doors to create a negative pressure maintain in the laboratory.

All fume cupboards and suction devices are designed so that a maximum pressure drop of 150 pascals is not exceeded is, so that this as a constant value for the on-site Exhaust air can be prescribed. Deductions with increased Volume flow, for example through filters, is given a push fan to ensure the uniformity of the exhaust system. By consistently closing the sliding window of the Deductions if not used are all deductions that are not in Operation are kept at the minimum air volume value. Thereby can have a maximum of 50% simultaneity the peak demand are assumed, so for this reason all supply and exhaust air lines are reduced by a factor of 50% can.

The room controller 8 can, if no building management system is provided, which is the case, for example, when none Laboratory air conditioning takes place via analog output signals Actuate flap 17 directly.

If that from the volume flow values of the consumers on Room controller 8 formed signal for controlling the flap 17 in Supply air line 16 assumes a value that is below the value for the smallest prescribed supply air quantity, then the flap 17 set so that this minimum prescribed supply air quantity is ensured. This value, which is usually used for a There is an eightfold change of room air when controlling the Flap 17 never fell below.

If the laboratory is equipped with air conditioning then there are different ones in the room of the laboratory Temperature and air quality sensors for air conditioning technology. It can happen that when using many devices in the Laboratory the amount of exhaust air especially when closed Sliding window of the deductions 3 is no longer sufficient to ensure a safe To ensure cooling. If the air conditioner detects that the extracted and the supplied air quantities too small are, it can the room controller 8 a higher via a line 10 Specify the setpoint. The room controller 8 can then in turn the subordinate controllers, for example controller 6 of the Deduction 3, so that the air volume flows also closed sliding window can be increased, so that more fresh air is also supplied to the room. It is also possible, to open the sliding window accordingly, so that the Controller 6 automatically increases the exhaust air volume. One for the air conditioner own room exhaust air with own room exhaust air controller and A separate room air damper is therefore unnecessary, since these functions by the regulators integrated in the fume cupboards can.

The signal transmission between the room controller 8 and the connected units can be used with analog signals up to 10 V or 4 to 20 mA signals. However, it is also possible a bus technology, for example a two-wire or Three-wire bus technology. Reduced to this case the number of interfaces is considerable and is guaranteed that the building management system at any time from the room controller 8 via the Operating states can be informed.

The laboratory ventilation system described above has the advantage a simple ventilation system, with all measuring and control elements are basically integrated into the laboratory equipment. These include all deductions, all other suction systems, all ventilated cupboards as well as the necessary ceiling and Floor air outlets. These components are required on site only a predetermined minimum pressure and regulate their air volume flows automatically after fluctuations. The furniture manufacturer therefore only needs a single connection point for the total indoor air per line.

Preferably, the training is such that in vertical Shafts the exhaust pipes run through the building, whereby the central fans sit in the roof or in the basement. This makes it possible to control the entire exhaust air flow in the laboratory to standardize. Standardized ones are therefore sufficient Ventilation ducts that go across the entire width of the laboratory. These can be prefabricated in the factory, delivered to consumers attached and connected to the on-site through line. Also on the supply air side can be done in the same way be moved. Another part of the room is also running vertical supply line through the room. This too Supply lines can be connected to prefabricated supply air systems become. It is only necessary to put a flap between the supply lines and the room line, which controls the volume flow. Especially with the supply air can instead of supply air ducts also brick walls or lightweight concrete walls serve as supply air lines.

With such a design, there is an almost non-crossing Operation of exhaust and supply air lines. The structure, a large number in the laboratory ventilation systems that have been used up to now of different pipelines, can reduced in height and cubature and clearly become cheaper. This is made possible by the fact that everyone Components as well as the self-regulating consumers who make it possible to use measuring and actuating elements in the tightest of spaces, have uniform pressure drops.

In a specific embodiment of the above laboratory ventilation system are vertical through lines for the Exhaust air in a vertical passage through the corresponding building Arranged in a wall between the hallway and shaft is integrated into the laboratory. Branch in front of this shaft Laboratory branch lines leading to individual consumers, for example lead to two deductions. However, others can Suction devices are connected. On the other side of the The supply duct for the supply air is located in the room. This can be inside the room but also outside the building to be appropriate. Supply lines branch from this supply air shaft for the room from that represented by that in Fig. 1 Flap 17 can be controlled. On these supply lines hang the actual room air outlets that run extra can, but can also be integrated in the channel. Because of the intersection-free operation of supply air and extract air and due to the simple pipes only need a room height of approx. 3.20 m, which leads to a floor height of 3.40 m. Standard laboratories are planned and built about 1 m higher so far this results in considerable cost savings. With the above For example, the location and location of the inlet and outlet pipes can be replaced at any time, so that the exhaust air lines too can run outside the building while the supply air lines run in the building.

Another reason for the lower design of the building is that the building is no longer for the peak load must be interpreted, but for a simultaneity of approx. 50% can be built. The previous laboratory ventilation systems work in continuous operation and are at 100% peak load designed. The reason for this is that experience is shown has that even with sliding window controlled deductions Many sliding windows are open that the system is at maximum load must be built. In that in the manner described above the sliding windows when the fume cupboards are not used the system can be dimensioned in advance to 50% of the peak load become. That means, for example, that in a laboratory with multiple deductions the basic load with all continuous Consumers and all suits in the closed sliding window position is set. If a sliding window is opened, the deduction increases to 50% of the peak load. We then worked two deductions, so the system can briefly over the Supply line in the room can also reach peak load operation. However, it can be assumed that times are relevant are limited. The 50% peak load that is obtained relates all of the building management systems, which can be reduced by 50%. Can in a laboratory a peak load can be driven for a short time.

Claims (7)

1. A laboratory ventilation and aeration system for a laboratory room having several air consumers (1, 3) including at least one exhaust with a sliding window which are connected to a single common exhaust air duct (12), with a room air controller (8) which receives the actual values of the exhaust air volumes of the air consumers and forms from them, a control value for controlling the air intake control devices (17) of the air intake line (16), characterized in that all the air consumers are constructed such that they do not exceed the same maximum pressure drop of 150 Pa, all the air consumers have an exhaust air control device (2, 6) and at least one exhaust is designed so that it automatically closes the sliding window and is thus converted to an operating state with lowest exhaust volume when no one is working in front of the exhaust.
2. A laboratory ventilation and aeration system according to Claim 1, characterized in that the air intake line (16) and the exhaust air duct (12) are dimensioned for a maximum of 50 % of the peak air exhaust and intake volumes.
3. A laboratory ventilation and aeration system according to Claim 1, characterized in that the value of a specified minimum exhaust air volume is also supplied to the room air controller (8), and the room air controller (8) controls the intake air control devices (17) so that the specified minimum exhaust air volume is always ensured regardless of the required exhaust air volumes of the air consumers (1, 3).
4. A laboratory ventilation and aeration system according to claim 1, 2 or 3 for a laboratory room equipped with an air conditioning system, characterized in that the value of the air demand of the air conditioning system is applied to the room air controller (8), and when the control value for the air intake control equipment (17) resulting from the exhaust air volumes of the air consumers (1, 3) is below a value which ensures the air demand of the air conditioning system, the room air controller (8) controls the air intake control devices (17) primarily according to the air demand of the air conditioning system.
5. A laboratory ventilation and aeration system according to Claim 3, characterized in that when an air intake volume greater than the value obtained on the basis of the control value of the room air controller (8) from the exhaust air volumes of the air consumers (1, 3) is needed, the sliding window of the exhaust (3) is opened so that the exhaust air volume whose actual value is applied to the room air controller (8) is increased accordingly.
6. A laboratory ventilation and aeration system according to any one of the preceding claims, characterized in that the control value for the air intake control devices (17) is applied by the room air controller (8) to a building control system which in turn controls the air intake control devices (17).
7. A laboratory ventilation and aeration system according to any one of the preceding claims, characterized in that all the measurement and control systems are integrated into the laboratory room equipment.

Images