WO1986007129A1

WO1986007129A1 - Method and device for optimum heating, ventilation and exhaust air decontamination in industrial locals

Info

Publication number: WO1986007129A1
Application number: PCT/EP1986/000299
Authority: WO
Inventors: Christian Koch
Original assignee: Christian Koch
Priority date: 1985-05-21
Filing date: 1986-05-16
Publication date: 1986-12-04
Also published as: EP0225896A1; DE3518143A1

Abstract

Supplied air is sucked into a tower (1) on top of the roof, heated by heat exchangers (8, 10) and blown into the working area of the locals. The cooled water or brine quantity (17, 19) is used for the cooling and condensation of exhaust air in the heat exchangers (11, 12).

Description

Process and device for optimal heating, ventilation and

Exhaust air cleaning of industrial halls Summary of the patent application and additional patent application Process and device for optimal heating, ventilation and exhaust air cleaning of industrial halls P 35 18 143.5 and P 36 11 434.0 as well as G 85 14 955.1 and G 86 09 196.4

Process and device for optimal heating, ventilation and exhaust air purification of industrial halls

The invention relates to a method and a device for energy-saving heating, ventilation and exhaust air purification of industrial halls with a high air quality in the worker zone and high-quality exhaust air purification of the exhaust air discharged from the hall.

According to the state of the art, halls are today heated directly by warm air, arm water or radiant heating, vented with an exhaust air fan and possibly dust filter in the exhaust air and ventilated by partial recirculation of the exhaust air or by open windows or doors.

When returning the exhaust air, both recirculated air and fresh air additive are used, with the air being led into the hall in the form of an air heater. Disadvantages of the current solution are a high energy expenditure for heating the hall, mixing in the bad air from the upper region of the hall and the return of bad air during the air recirculation.

The energy expenditure is also partially attempted to be reduced by the exhaust air being combined with the supply air in heat exchange is brought regularly. In this case, however, only a very modest amount of heat is removed from the moist exhaust air compared to the dry supply air, so that this measure brings only modest success. It has now been found that the heating and ventilation problem can be solved independently of the different hall heights by supplying the lower air layer or the lower room with a height of 2 m with an optimal air and sensation temperature quality without being too large - the poor air quality of the upper hall layers was due to this layer.

A central element for the implementation of the invention is a supply air tower which sucks in fresh air through air intake openings above the roof as well as recirculated air through intake openings below the hall roof by a fan. The suction openings above and below the roof are connected to an interchangeable lockable mechanism, which on the one hand closes the outside suction during the heating phase and opens the outside air suction, on the other hand opens the outside suction and closes the outside air suction when the exhaust air blowers go into operation.

It has been shown to be advantageous if the fan speed is adapted continuously or in stages to the performance of the suction fans by means of a central comparison of the two systems, for example static converters for the motors of the air tower fans. The supply air, which is drawn in via the roof, is heated and additionally humidified via heat recovery from the high-energy exhaust air.

With regard to the humidification, it has been shown that preheating the air before the injection is not necessary, so that it is favorable for thermodynamic reasons to carry out the injection before the heat exchanger package, the spraying of the water being carried out as finely as possible in order to avoid the residues remaining during evaporation Discharge salts in dry form from the heat exchanger without accumulating them there.

It has also been found to be advantageous in the case of humidification that a single row of the heat exchanger package is connected upstream of the humidification in order to prevent the spray nozzles from freezing in winter.

Since the outlet openings of the processed fresh air are close to the work zone of the personnel, it has proven to be advantageous to set the four sides of the outlet openings separately by means of pre-throttle grilles. In the event of changes in employment relationships, this default setting must be easy to readjust. This means that both the direction of discharge and the quantity can be set separately on each side. The different supply and exhaust air volumes in the hall ventilation also have their effects on the heat recovery. It has now proven to be advantageous to gradually regulate the heat pump depending on the return temperature of the evaporator circuit, since the reduced supply of exhaust air also increases in the heat pump leads to strong cooling of the brine in the evaporator of the heat pump, so that in that case the heat pump switches back gradually and the circulating amount of brine in the evaporator circuit is reduced. In the supply air flow, heat exchange in countercurrent with the fresh air produces water temperatures so low in the heat exchangers that this water or brine in the heat exchangers of the exhaust air not only cools the exhaust air, but also condenses the moisture contained in the exhaust air at least is partially achieved.

This condensation of the water vapor in the exhaust air leads to a coupled separation of the solid, liquid and gaseous or aerosol-type pollutant particles contained in the exhaust air and represents an excellent exhaust air purification. The pollutant purity achieved often significantly exceeds the required purity.

To improve exhaust air purification and heat utilization, a cooling circuit can also be switched on in the water circuit between the supply air towers and the exhaust air heat exchangers, which improves the effects, particularly also at higher outside temperatures, with regard to heat recovery and exhaust air purification.

In the case of exhaust air quantities containing a lot of dust, a solid matter separator or filter can also be connected upstream of the cooling section of the exhaust air.

To cover the heat requirement, in particular the transmission heat requirement in the heating phase and at particularly low outside temperatures, or at low machine temperatures. heat build-up, the supply air in the towers can also be heated up further by heating the air with heat from a heating circuit via a heat exchanger. The use of a radiation or heat wave system has also been shown to be advantageous, which supplies the heat in the hall in particular in the morning heating-up phase without excessive vertical mixing of the air in the hall. The heating-up time can be shortened due to the special nature of the heat transfer by radiation. However, it is also conceivable to combine the supply air heating by means of heat recovery and low-temperature heating and possibly waste heat recovery from liquid-cooled machines, waste incineration and radiant heating or heat wave heating. 1 shows the construction of the supply air tower according to the invention. The weather protection grilles, which are located on two opposite sides, are designated by 1. On the inside thereof are the supply air flaps 2, which are connected via a linkage 5 to the recirculation air flaps 4 arranged underneath.

6 designates the fan, which is driven by a steplessly adjustable three-phase motor 14 and which, contrary to the buoyancy by the heat exchangers, leads the air through the tower via the outlet grilles 11 directly into the working zone of the hall. A heat exchanger element 8 is arranged between the nozzle assemblies of the air humidification device 9, which can also be used for occasional cleaning of the heat exchangers, and the fan 6, thus in winter the cold supply air is warmed up to such an extent that the nozzle pieces 9 are protected against freezing. The humidified air is heated to a comfortable temperature in the heat exchanger 10. A filter is arranged downstream of this heat exchanger, in which, among other things, the dusty salts are removed from the air humidification. The two heat exchangers 8 and 10 can also be designed as 1 heat exchanger, as can be seen in FIG. 2 if the humidification 9 is arranged above the heat exchanger, for example, and is equipped with an electric heater 15 as protection against freezing of the line. The tower can be made of galvanized sheet steel or plastic if the relatively heavy heat exchangers are self-supporting in the lower part of the tower.

The individually adjustable outlet grilles are designated by 11, which enable the fresh, heated outside air to be fed individually into the work area of the hall on all sides. The drip water trough is designated by 12, which drains off excess injection water in winter or condensate accumulating in extreme summer conditions. The small condensate drain 14 conducts the moisture in a targeted manner, for example through the floor of the hall into the gravel-containing layer below.

In the foot of the supply air tower there is an empty space 13 which can be used to accommodate the electrical equipment. The heat exchangers 8 and 10 in FIG. 1, or the heat exchanger 10 in FIG. 2, symbolize the supply of heat from: 1.) cooling of the exhaust air in the 1st stage with water flow through the heat exchanger 2.) cooling of the exhaust air in the second stage with brine-flow heat exchanger, which is connected in a heat pump circuit working as a refrigerator. 3.) Low-temperature heating, for example from waste incineration, waste heat recovery from liquid-cooled machines and / or a heating or district heating system. 3 shows the interaction of the components according to the invention. In the supply air heating, 1 is the supply air tower with the heat exchangers 8 and 10, in the heat recovery part of the exhaust air 11 is the water heat exchanger which cools the exhaust air with the cooled water of the supply air tower and thereby heats the water. A further heat exchanger 12 can be arranged downstream of this heat exchanger, which uses the evaporator 41 of a heat pump 16 to extract further heat and moisture from the exhaust air. The resulting dirty condensate 13 is cleaned by a condensate treatment 14 and introduced at 15 into the drain line.

The heat pump 16 cools the exhaust air in winter through the brine of the evaporator 41 and in summer it heats the exhaust air with the water from the evaporator circuit 17. In this case, the heat exchanger 12 is cooled by the exhaust air cooled with the injection of water from the nozzles 18. This water Steam-containing exhaust air is then no longer heated to such a high level via the warm water accumulating in the condenser circuit 19, so that the heat pump delivery number is not worse in summer than in winter. Another effect of the injected water is to take over the cleaning of the exhaust air, which is caused in winter by the condensation of the water vapor when the air cools down. The regulation of the heat pump by different supply and exhaust air quantities is accomplished via the return temperature 28 of the evaporator circuit 17 in such a way that, with a reduced exhaust air quantity and a constant return temperature, the brine flow quantity is reduced by throttling the control valve 30. As a result, the heat available in the evaporator 41 of the heat pump 16 becomes smaller, which results in a reduction in the output of the compressor 29 of the heat pump.

Fig. 4 shows the piping with the fittings necessary for the summer-winter changeover. The direction of the arrow indicates the direction of flow of the water or brine circuit during winter operation. With 50 the connection direction to the supply air towers is indicated, with 51 the connection direction of the supply air towers. 5, based on FIG. 4, shows the direction of flow of the water or brine circuit during summer operation.

In summer, the circuit according to the invention thus stands by cooling the water in the heat exchanger 11 and the cold brine of the heat pump has a cooling capacity potential for the supply air towers which can limit the hall temperature in summer by 22 ° C in most hours. The circuit water 19 in FIG. 3 for the heating or cooling of the supply air towers thus passes through 1, 2 or 3 stages on the heating or cooling side, depending on the embodiment, both in summer and in winter. In winter, the circulating water is heated by the heat which is extracted from the exhaust air via the heat exchangers 11 and 12 with the connected heat pump and by the reheating of a warm water-heated reheating heat exchanger 25. The cooling of the water takes place in countercurrent from bottom to top . The temperature of the supply air is heated to the humidification temperature, humidified and reheated to supply air quality with the evaporation of injected water.

In summer, the circulating water is cooled with the cooled and moisture-saturated exhaust air in a heat exchanger (11). This circulating water is further cooled by the heat exchanger, which is cooled with the brine of the evaporator circuit.

The circulating water cooled in this way cools the supply air flow from the supply air towers in counterflow. The hot water generation for the reheating of the air in winter is done by the low temperature heater 20, which can be coupled with a heat wave heater 21. With this hot water, the heating circuit 22 can do not only that Continue heating circuit for the supply air towers, but also heat conventional radiators, in particular for the low-temperature heating of offices (23), and heat service water in a heat exchanger 24. The special features of the method according to the invention are explained in more detail in a special embodiment (winter operation).

An 18,000 m2 and 9 m high production hall is to be kept at a temperature of 5 grdC outside of production time in winter and at 20 grdC during production time, whereby an operational exhaust air volume of 160000 m3 / h is required. The supply air is supplied directly from the roof via supply air towers, whereby each tower is designed for a supply air volume of 10,000 m3 / h each. In the production-free time, the hall is kept at temperature by a pure recirculation mode, which is characterized in that the exhaust air blower is switched off, the supply air flaps 2 are closed and the recirculation air flaps 4 are open. The required transmission heat of 490 kW is covered by the fact that the fan 6 of each tower sucks in 3800 m3 / h and pushes it through the heat exchangers 8 and 10. By supplying 30.7 kW per supply air tower, the circulating air is heated back to 25 ° C and passed through the outlet grille 11 into the hall. In air recirculation mode, there is no air humidification and the heat pump unit is also switched off. Supply and exhaust air quantities can be throttled accordingly for special production conditions. This happens both by reducing the air volume per tower by reducing the speed of the supply air fans and by switching off the fan. Outlet temperature limiters ensure that the circulating water in the heat exchangers of the supply air towers is cooled evenly.

The -15 grdC cold supply air is sucked in through the roof into the supply air towers and heated to a humidification temperature of 7 grdC in heat exchanger 2 with the supply of heat of approx. 55.8 kW / supply air tower. So much moisture is supplied to the air via the humidification device until a rel. Humidity of 95% is reached. The addition of moisture itself can take the form of a vapor or aerosol, since in both cases the salts dissolved in the moisture fall out in dust form when heated in the heat exchanger 10 and are separated out in the filter 7.

The required evaporation arms of 60 kW / tower and the remaining heat of also 60 kW / tower for the natural heating of the air to comfort temperature takes place in the heat exchanger 10. On the way through the supply air tower, the circulating water is cooled from 35 ° C to 6 ° C. At this temperature, it reaches the heat exchanger 11, where 870 kW are supplied to the water by cooling the exhaust air from the hall. During this heat exchange, the exhaust air in stage I cools down to 10 ° C, while the water is heated from 6 to 15 ° C. In the second cooling stage, the exhaust air reaches a temperature of 5 ° C. The condensate 13 which precipitates at this rate of approx. 540 l / h binds on the one hand the most finely distributed in the air Dust and flushes it out; on the other hand, the condensate binds the aerosols coming from the spraying, so that a max. possible exhaust air purity is achieved.

The heat of 445 kW extracted from the exhaust air in the second cooling stage is fed to the circulating water via a heat pump circuit, which warms up to 20 ° C when flowing through the condenser 42 and then to 35 ° C in the post-heating heat exchanger 25. The 35-degree water is pumped to the supply air towers, where it cools down again, the circulating water circuit is closed.

In the heat exchanger of the low-temperature heating 20, the water heats up from approx. 40 grdC to 61 grdC. A partial flow is branched off for the hot water preparation 24, which requires 30 kW. The water cools down to an average of 60 grdC.

After the hot water preparation, a further partial flow of water with a heat content of 290 kW reaches the heating system 23 for the office wing and the social rooms. In the post-heating heat exchanger 25, 1450 kW are reduced, the temperature on the low-temperature heating falling from 60 to 40 ° C, while on the side of the circulating water for ventilation rises from 20 to 35 ° C, the heating circuit is closed. Another exemplary embodiment is intended to explain the device according to the invention in more detail.

The warm brine flow is introduced into the heat exchangers of the supply air towers at a height of 3 m. The heat exchanger 10 of a supply air tower has the dimensions 1.33 m and 1.17 m and one Height of 1.5 m. It is located in a supply air tower made of galvanized sheet steel with cross-sectional dimensions of 1.38 and 1.22 m. About 0.5 m above the heat exchanger 10 are the air humidification nozzle sticks, which add about 50 l / h of water to the air stream in a vapor or aerosol state.

Below the heat exchanger 10 there is an approximately 5 cm thick filter mat across the air flow, which fills the entire cross section, below which the adjustable outlet grilles with the outer dimensions of 1 mx begin at a height of approximately 2.5 m on the side walls of the supply air tower 0.5 m. At a height of 2 m, the cross-sectional area of the tower is filled with a drip tray, which also forms the ceiling for the electronics room located in the base of the tower. Immediately above the nozzle sticks for air humidification is a narrow heat exchanger element at a height of 4.5 m and 5 m, above which, at a height of 6 m, is the fan.

Below the hall ceiling, at a height of approx. 7 m above the hall floor, there are two opposite air circulation flaps measuring 1 m x 0.5 m. They are connected via a motor-controlled linkage to the fresh air flaps above the hall roof, which have the same dimensions. When the exhaust air blowers, which are located in a separate filter house, start, the air recirculation flaps close while the supply air flaps are opened.

The cold water pipe of the circulating water is in the heat exchanger for the hall exhaust air with the dimensions 4.4 mx 4.5 m and the spraying exhaust air with the dimensions 2.5 m x 2.5m conducted. Both heat exchangers have a depth of 0.7 m. Immediately behind is the condensation heat exchanger with the same dimensions, but with a depth of 0.3 m. At the end of the cold water pipe of the circulating water are the condenser of the heat pump circuit with the dimensions 0.5m x 0.5m xl, 5m and the heat exchanger for reheating with the dimensions 1.0m x 1.0m x 2.0m. The heat exchangers of the heat pump unit and the reheating, including all pumps, are installed compactly in one room. In the same room is the heat exchanger for the low temperature heating with the dimensions 1.5m x 1.5m x 0.5m. The distribution station for the inflows and outflows of the heating system for the office wing and the social rooms is located on the supply and return sides of the low-temperature heat exchanger.

Claims

1. Process for generating a high air quality from industrial halls with high air exchange, heat recovery from the exhaust air and exhaust air purification of the exhaust air, characterized in that the supply air is drawn in through a roof with a fan via one or more heat exchangers heated and possibly moistened with an injection and the air thus prepared is blown into the working zone of the hall, usually of a height of 2 m, via supply air grilles or nozzles and the amount of water or brine cooled in the heat exchanger zone in winter for cooling and condensing the Exhaust air is used, the condensation of the water vapor in the exhaust air cleaning the exhaust air from aerosols, dust and vapors.

2. The method according to claim 1, characterized in that the supply air tower enables the warming and heating of the hall by heating in recirculation mode and the treatment of the outside air as supply air for the extracted exhaust air.

3. The method according to claim 1, dg that the switchover from the heating phase to supply air operation takes place in that the openings located below the roof are closed by a control flap and the supply air flaps above the roof are opened analogously. The command to do this is triggered by switching on the exhaust air fans.

4. The method according to claim 1, characterized in that the injection is connected upstream of the heat exchanger package of the Sole¬ heat exchanger, wherein if necessary a single heat exchanger layer can be connected upstream to prevent the spray nozzles from freezing.

5. The method according to claim 1, d. G. that the heat recovery for heating the brine for the supply air tower takes place when the heat pump is switched on in such a way that the reduced suction quantity leads to a reduced brine flow quantity of the heat pump evaporator and thus to a gradual switching back of the heat pump. ■

6. The method according to claim 1, characterized in that for increasing the effect of heat recovery, a further cooling of the exhaust air with the brine of a heat pump is carried out and the resulting heat of condensation of the heat pump is used to further heat the liquid circulation for the supply air tower.

7. The method according to claims 1 to 6, characterized gekenn¬ characterized in that the circulating liquid is further heated by heat exchange with a medium of a heating circuit, so that the supply air generated in the supply air tower reaches the desired temperature.

8. The method according to claims 1 to 7, characterized gekenn¬ characterized in that for cooling the supply air, the Kreislaufwas- water_ cooled by the humidified exhaust air, if necessary by the cooling capacity of the evaporator of the heat pump further cooled, also in counterflow to the supply air is heated in the supply air tower.

9. Apparatus for carrying out the method, characterized in that it consists of a flow envelope which stands on the floor of the hall and has an opening through the hall roof and which has the following elements in the plastic or metal flow envelope from top to bottom: Rain cover, supply air and recirculation air openings with shut-off flaps, fan, lighting device, heat exchanger, fine filter, adjustable supply air grille or nozzles, drip water drip tray and condensate drainage

10. The device for carrying out the method characterized in that the supply air tower has two mutually closable suction openings, each of which is above and below the roof, equipped with a motor-operated adjustment mechanism which is operated by the switch-on mechanism for the suction fans is that the openings above the roof open when the suction is switched on.

11. A device for performing the method, characterized in that a nozzle assembly for injection water are located above the heating heat exchanger of the brine heater, which may also have a small heat exchanger part upstream to prevent icing of the nozzle assembly in winter.

12. Device according to claims 9 to 11, characterized gekenn¬ characterized in that at least one liquid line leads to heat exchanger units which are in the exhaust air flow and from there via a pump directly or to one Return another hot water heat exchanger of a heating circuit to the heat exchanger of the supply air tower.

13. Device according to claims 9 to 12, characterized gekenn¬ characterized in that there is a water injection valve in the exhaust air flow before the exhaust air heat exchangers and, if appropriate, a humidification grille behind it with an underlying drip water pan.

14. Device according to claims 9 to 13, characterized gekenn¬ characterized in that a heat pump for the heat transfer between the exhaust air and supply air is available.

15. A device for performing the method according to claims 9 to 14, characterized in that in the brine circuit of. Evaporator of the heat pump is a throttle valve, which throttles the circulation close by a thermostat.

16. The device according to claims 9 to 15, characterized gekenn¬ characterized in that a condensate agreement is turned on in the condensate drain of the exhaust air.

17. Device according to claims 9 and 12, characterized in that a heat wave heating takes over or supports the heating phase of the hall.