WO2015074100A1

WO2015074100A1 - System and apparatus for mine face cooling

Info

Publication number: WO2015074100A1
Application number: PCT/AU2014/001062
Authority: WO
Inventors: Neil Mccoubrey
Original assignee: Individual
Current assignee: Individual
Priority date: 2013-11-20
Filing date: 2014-11-20
Publication date: 2015-05-28
Anticipated expiration: 2016-05-20
Also published as: AU2018267592A1; AU2018267592B2; AU2014353870A1

Abstract

An assembly for cooling air in a mine environment comprising: a water supply, a source of compressed air, a chiller unit having at least one inlet and an outlet. The chiller unit receives water from the water supp!y and compressed air from the source of compressed air. A venturi receives chilled water from the chiller unit and compressed air from the source of compressed air. The venturi delivers cooled air via a mist nozzle associated with the venturi into the environment requiring air cooling.

Description

SYSTEM AND APPARATUS FOR MINE FACE COOLING

BACKGROUND

[0001] This invention relates to mine cooling apparatuses and systems and more paiticularly the present invention relates to a self contained cooling assembly which is particularly useful, though not exclusively in underground mine environments and which is safe to use in high risk environmental mine conditions prone to ignition. The invention further relates to a portable mine environment cooling system which employs a Venturi air mover and chiller unit using compressed air and water supplied at ambient temperature which is delivered to a hot and humid air space to cool the space to comfortable and safe levels. The system and assembly of the present invention is arranged to ensure safety in a mine environment and to create a more favourable working environment to enhance comfort and productivity.

[0002] The cooling assembly according to the invention is .lightweight, self contained and is constructed to ensure suitability for transportation and deployment in mines and ease of assembly and disassembly. The present inventio is particularly advantageous where there is difficult access to a work space or where cooling is required in a confined space.

PRIOR ART

[0003] it is important to ensure compliance with strict regulatory frameworks that mine environments be well modulated to ensure safety, good air quality and tolerable ambient conditions for mine face workers. There are in existence a variety of apparatuses for cooling the environmental air mine environments.

[0004] Once such example is disclosed in publicatio W 20I2025839 (A2) which discloses an invention which L¾$"irelates to a central, air-conditioning system for mine excavations, in particular for cooling mine excavations in mines. The central air- conditioning system for mine excavations comprises a surface climate station connected in a closed system with mine face coolers via a pressure exchanger. The invention comprises a primary high pressure cycle equipped with at least two pressure exchangers connected in parallel with each other and a separate secondary low- pressure cycle connected to a pump system with air coolers situated in exploitation sites. The system is equipped with three pressure exchangers connected in a secondary low pressure cycle with a cooling units assembly and air-coolers. The cooling medium in the primary high pressure cycle is ice water.

[0005] Another example of a ventilation and cooling apparatus for mines is disclosed in Abstract of GB534432 (A). This apparatus comprises a suction conduit extending from the surface to the working faces, and is connected with a pump for evacuating the mine air and causing adiabatie expansion into the conduit t cool it thereby utilizing the conduit system as heat exchange means to cool the mine air. One inlet is restricted by a Venturi throat which leads into an expansion chamber having fins , or a constricted, opening leads to a chamber, a blower being arranged in the conduit and a vacuum gauge is provided. A nozzle is controlled by a valve. The conduit itself acts as heat exchanging means. A filtering head controlled by a valve may be employed. The walls of the conduit may be fluted longitudinally to increase their effective area. An expansion chamber may be connected to the suction duct b a pipe with the inlets for mine air with valves controlling the rate of air flow. The rate of air flow may be controlled automatically by a valve opening against a spring in compression, or controlled either thermostatically by a heat sensitive strip, or by electrical means, or by a governor actuated by a wind vane in the conduit.

[0006] In a mine environment there are dangerous gases which can be easily ignited. To avoid this risk mine equipment must be flash and spark proof. Ideally any part of any mine system which is a source of ignition is ideally placed away from dangerous environments. Cooling should be mechanical and if powered by electrics the power sources should be located remote from the mine face.

[0007] Another cooling unit is disclosed in DE I 547422 (CI) which teaches an inflow unit comprising a number of concentrically arranged double wall cooling cylinders, which between them form ring-shaped inflow channels. The outflow unit is a nozzle tube, connected coaxially to the inflow unit. The drive nozzle is located centrally in the commencement part of the outflow unit. The double wall cooling cylinders are connected to a deep cooling medium conduit and the drive nozzle is connected to the compressed air conduit and produces a drive jet in the outflow unit. The cooling power can be controlled or regulated by the adjustment of the quantity flow of the deep cooling medium and/or the quantity flow of the compressed air.

[0008] Another unit is disclosed in DE19517633 (Al) which teaches concentric double-walled cooling cylinders as heated-air entry giving annular inflow channels and a cooled-air ejector nozzle tube coaxially adjoining the inflow unit. The nozzle lies in the centre of the initial sector of the ejector unit and the cylinders are joined to the cooling agent line and are flowed by this agent to produce an ejecting jet in the nozzle. Cooling performance is adjusted by varying the flow volume of the agent and or that of the compressed air. The cylinders are preceded by inflow blades and the nozzle forms a cylindrical tube or again a venturi nozzle with attached diffuser. all within a sound-absorbing pipe encased in perforated sheet metal

[0009] There are methods of cooling the air in underground mine workings and like places which consists in providing a suction conduit system extending from the surface to the underground shafts and working places and which includes means at the surface for evacuating air from the conduit system so as to create a partial vacuum therein. There are means to cause controlled adiabatic expansion of the mine air into the conduit system to cool it, and to utilise the conduit system as heat exchanging means to extract heat from the mine air in contact therewith. The work areas are cooled by the heat exchange from the position of the controlled adiabatic expansion of the mine air into the conduit system, upwardly to the surface. Expansion chambers acting as additional heat exchangers are provided at intervals throughout the conduit system with large cooling surfaces provided to ensure maximum transfer of heat from the mine air to the cooled air passing out through the conduit system.

[0010] Chinese publication CN101344009 discloses a cooling system used for a mine and a cooling method. The system comprises an ice slurry preparation device, a high/low pressure heat exchanger and a working face cooler. The ice slurry formed by the ice slurry preparation device is communicated with the high pressure side of the high/low pressure head exchanger by an ice slurry conveying pipe and a return water pipe. A high pressure ice slurry conveying pump is arranged on the ice slurry conveying pipe. The working face of the cooler if communicated with the low pressure side so as to form cooling circulation under the mine and a cooling and temperature reduction to the mine by the flowabiiity and the large latent heat of the flowing ice slurry and has the advantages of good temperature reduction effect, small occupied space and small facility investment and low operation cost.

[001 1] Another cooling system is disclosed in Chinese publication CN200971787 which discloses a mine work face cooling system adopting a cold wind preparing device comprising a spray wind box and a blower. The spray wind box is composed of a wind in fence, a wind out mouth a water spray calandria whose top is provided with tlie nozzle are arranged between the wind in fence and the wind out mouth. The water spray calandria is lead into the ref igeration machine set through the water in main pipe to produce chilled water. The bottom of the spray wind box is the wind box water falling pool which is internally provided with the wate our main pipe. The water out main pipe sends the falling chilled water back to tlie refrigeration machine set. The blower which is connected with the wind out mouth forms wind box sub pressure and sends the cold wind to the underground through a ventilating pipeline. Utilizing the chilled water spray to realize the preparing cold wind with big flow rate big temperature difference and big enthalpy difference can reduce the times of heat changing process bring down the heat transferring temperature difference and reduce the refrigerating capacity loss of the middle process applicable for sub vertical tnineshafts and extending to the coal extracting work face to reduce the temperature.

[0012] Other cooling and dehumidification systems are disclosed in Chinese publications CN 201344042 and CN 2016795513 which are incorporated by reference herein.

[0013] There is an on going need to provide a more efficient alternative to the known mine cooling systems and which is simple to install, efficient in operation, portable and which is both safe and economic to ran and manufacture. INVENTION

[0014] The present invention provides a self contained mine cooling system and apparatus which is particularly useful, in underground mine environments. The present invention is safe to use in high risk environmental mine conditions prone to ignition and pollution. The invention further relates to a portable mine environment cooling system which employs a Venturi air mover and chiller unit using compressed air and water supplied at ambient temperature which is delivered to a hot and humid air space to cool the space to comfortable and safe levels. The system, and assembly of the present invention is lightweight, self contained and is constructed to ensure suitability for transportation and deployment in mines and ease of assembly and disassembly. The apparatus is arranged to ensure safety in a mine environment and to create a more favourable working environment to enhance comfort and productivity. The cooling assembly according to the present invention is particularly advantageous where there is difficult access or where cooling is required in a confined space, remote

[0015] Although the invention will be predominantly described with reference to its application in a mine environment, it will be recognised b persons skilled in the art that the invention has a variety of field applications beyond those to be described by way of example. The present inventio is particularly advantageous where a self contained portable unit which is readily assembled, i required for mine cooling. Each portable assembly is constituted by the necessary safety and maintenance equipment and fittings for performing in mine cooling. The present invention is particularly advantageous where there are no maintenance and repair facilities readily available as the apparatus has parts which a durable and require little or no maintenance. 0016] In. one broad form the present invention comprises: an assembly tor cooling air comprising: a water supply, a source of compressed air, a chiller unit having at least one inlet and an outlet; the chiller unit receiving water from the water supply and compressed air from the source of compressed air, a venturi which receives chilled water from the chiller unit and compressed air from the source of compressed air, wherein the venturi delivers cooled air via a mist nozzle associated with the venturi.

[0017] In another broad form the present invention comprises: a venturi for delivery of cooled air in an assembly for cooling air comprising: a water supply, a source of compressed air. a chiller unit having at least one inlet and an outlet; the chiller unit receiving water from the water supply and compressed air from the source of compressed air, the venturi receiving chilled water from the chiller unit and compressed air from the source of compressed air, wherein, the venturi delivers cooled air via a mist nozzle associated with the venturi when charged with cooled water and compressed air.

[0018] In another broad form of a method aspect the present invention comprises; a method of cool ing a m ine en vironm ent air using an assembly comprising: a water supply, a source of compressed air, a chiller unit having at least one inlet and an outlet: the chiller unit receiving water from the water suppl and compressed air from the source of compressed air, a venturi which receives chilled water from the chiller unit and compressed air from the source of compressed air, wherein the venturi delivers cooled air via a mist nozzle associated with the venturi; the method comprising the steps of; a) a connecting a water supply line to a chiller unit b) connecting a compressed air supply to the chiller unit; c) connecting a venturi unit to the compressed air supply d) connecting a water supply line from an outlet in the chiller unit to an inlet to the venturi; e). delivering air from the venturi unit chilled by water from the chiller unit. [0019] in another broad form the present invention comprises: an assembly for cooling a mine environment the assembly comprising: a chiller box including a water inlet line and a compressed air inlet line which respectively deliver water and air into the chiller box; a water exit line and air exit line exiting the chiller box; water exit line and air exit line respectively delivering water and air to a venturi air mover; wherein the venturi a chilled mist of air to a mine face thereby cooling the ambient air at the location of the mine face.

[0020] The present invention provides an alternative to the known prior art and the shortcomings identified. The foregoing and other objects and advantages will appear from the description to follow. In the description reference is made to the accompanying representations, which forms a part hereof, and in. which is shown by way of illustratio specific embodiments in which the invention may be practiced. These embodiments will be described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that other embodiments may be utilized and that structural changes may be made without departing from the scope of the invention, hi the accompanying illustrations, like reference characters designate the same or similar parts throughout the several views. The following detailed description is, therefore, not to be taken in, a limiting sense, and the scope of the present invention is best defined by the appended claims.

BRIEF SUMMARY OF DRAWINGS

[002 Ϊ] Figure 1 shows a schematic layout of a venturi assisted air cooling assembl according to one embodiment;

Figure 2 shows an elevatio view of the major components of the venturi cooling assembly according to one embodiment.

Figure 3 shows a graph of temperature versus time indicating the effect of the venturi cooling assembl on the ambient temperature.

Figure 4 shows a front elevation view of a. cooling unit housing assembled according to one embodiment. Figure 5 shows a rear elevation view of the cooling unit of figure 5.

Figure 6 shows an elevation view of an operational schematic layout of the cooling system according to an alternative embodiment.

DETAILED DESCRIPTION [0021] Although the present invention will be described with reference to its application i remote mine applications in the cooling of mine faces, it will be appreciated by persons skilled in the art that the assembly to be described below is suitable for alternative cooling operations.

[0022] The invention provides a pneumatic system that suppresses the air temperature directly in front of a cooling assembly unit to provide operato comfort, improved safety and productivity.

[0023] Figure 1 shows according to one embodiment, a schematic side elevation view of a cooling assembly 1 according to one embodiment. Assembly I comprises a compressed air source 2 which delivers iinfiltered compressed air to at least one filter, Preferably the compressed air is delivered to a first air filter 3 which is preferably a Micron 0.0 lw filter with an automatic drain. In series with filter 3 is a second filter 4 which includes activated carbon with automatic drain. Assembly 1 further comprises a water source 5 which delivers unfiltered water to a chiller unit 6. According to a preferred embodiment a series of water filters are provided comprising a Unicel 10, 20, 50 micron filter 7, a carbon filter 8 and a Doulton Sterasyl Sub Micron filter 9. The chiller unit 6 is preferably a vortex pneumatic chiller which includes at least one inlet and an outlet and which receives water from the water supply 5 and compressed air from the source of compressed air 2. A venturi air blower 10 receives chilled water from the chiller unit 6 and compressed air from the source of compressed air 2, wherein the venturi air blower 10 delivers cooled air via a mist /atomiser nozzle 12 injected with air and water, associated with the venturi air blower. Assembly 1 also comprises a water flow controller 13 and a heat exchanger 14 vented to the atmosphere 15. The venturi cooler assembly I comprising the chiller unit 6 and a venturi air blower 10 , fitted wit a spray nozzle mechanism 12 produces a chilled airflow (mist). Compressed air and water delivered at ambient temperature enter the venturi cooler and a chilled airflow spray mist is produced that supresses the air temperature in front of the air blower 10. Venturi Air blower is preferably manufactured from stainless steel and is mounted in a suitable mines approved housing which can be mounted on tripod, monorail or bolted to a support. The Venturi Cooler unit is designed to be easily relocatable. It can be placed on. the ground, attached to a monorail or mobile piece of equipment. The temperature is suppressed in front of the venturi air mover.

[0024] Figure 2 shows with corresponding numbering an elevation schematic view of the major components of the venturi cooling assembly 1 according to one embodiment. Shown is a water supply 5 which is fed to chiller unit 6 via supply line 20. At the same time compressed air 2 is deli vered to chiller unit 6 via line 21 and also to venturi 10 via supply line 22. Water from chiller unit 6 is delivered to venturi 10 via supply line 23, Cooled air flow 24 exits mist nozzle 12. The chiller unit 6 has two inlets comprising a water inlet 26 and an air inlet 27 and a water outlet 28. Venturi unit 10 includes an air inlet 29 and a water in!et 30.

[0025] Figure 3 shows a graph of temperature versus time indicating the effect of the venturi cooling assembly on the ambient temperature of the environment. From the graph a measured ambient temperature of 33C is supressed to a temperature of around ISC at a location of up to 5 meters from the outlet of the nozzle 12 of venturi 10.

[0026] Example Results of Use.

The following test example represented in figure 3 shows the results acliieved during a hot day. The aim for this test was to record the effects of the Venturi Spot Cooler (VSC), over a 5m distance and quantif - the wind chill levels that could be achieved. The schematics of Figure 2 shows the VSC and apparatus used in the test. The tests were carried out inside a warehouse in order to minimise cross flow effects from wind. Example operating parameters of The Venturi Spot Cooler. [0027] The following parameters were held constant during the collection of data. Compressed Air temperature 40C, Inlet water temperature 24C. Ambient Air temp 33C, Inlet Air Pressure 6bar, Distance to weather station 5m. The results are shown in figure 3.

[0028] A table of parameters which show temperature variations for various distances is set out below: Distance (m) Ambient Temp C Wind Chill C Velocity M/s 2 18 9.3 1 1.5

2.5 18 9.9 H

3.0 18 .10.7 9.5

3.5 18 12.2 7

5 18 14.5 2.8

[0029] An advantage of the present invention is that it is portable, lightweight, easy to assemble and is suitable for use in a potentially unsafe environment, such as a mine,

[0030] A source of water and compressed air is adapted to the basic equipment of a chiller unit 6 and venturi 10 to achieve the temperature reductions. According to the methodology the set up requires connection of a water suppl line along with the compressed air to the chiller unit 6. The Chiller unit 6 is connected to the venturi unit 10 along with the compressed air for delivery to the venturi unit.

[0031 ] The venturi enabled cooler has been provided to xtse compressed air and water supplied at ambient temperature to cool a hot and humid air space to comfortable and safe levels. Assembly 1 has been designed to meet the strict guidelines for equipment used in underground coal mines. The application of die Venturi cooler in underground mines is expected to reduce the dry bulb temperatures creating a more favourable working environment increasin human comfort and productivity. [0032] The embodiment previously described is one example only and it will be appreciated by persons skilled in the art that the configuration may be adjusted to accommodate size, weight and portability constraints such as its own transportation in land, sea and air vehicles. The present invention obviates the disadvantages of the prior art and provides other advantages which are apparent from the description herein.

[0033] For installation in a standard transport vehicle, aircraft or the like the assembly is constituted by an integrated assembly of equipment and fittings, so enabling it to be conveniently assembled and disassembled and loaded or unloaded at its place of use. Dimensions of components are defined according to the particular application or applications and according to the activities earned out. Ideally the In certain cases the dimensions may be adjusted to accommodate prescribed applications as well as fitting into a transport vehicle so the assembly may be moved conveniently from locat on to another.

[0034] Figure 4 shows a front elevation view of a cooling unit housing 30 assembled according to one embodiment. Figure 4 shows a unit housing assembled according to one embodiment. Housing 30 which is preferably of heavy dut stainless steel construction comprises at least one movable panel which is capable of movement between a first state in which the at least one panel encloses at least one internal space or compartment and a second state i which the at least one panel allows access to the at least one internal space or compartment 39. Included are a compressed air two stage filtration station 31 supplied by air lines 36 and 37 which includes a 0.01. micron particulate and activated carbon filter rated to 125 bar G. it will be appreciated that alternative filtration capacities and pressure ratings can be selected depending upon circumstances. Also included is a pneumatically operated water chiller station 32 which chilis water to a predetermined temperature within the preferred range of 5C-15C and a 3 stage water filter system 33 supplied by lines 34 and 3Swhich is rated to 80 bar G. There are automatic drains on the filters and isolation valves fitted to compressed air and water inlets and outlets. The venturi air delivery unit 10 as shown in figure 2, is preferably of lightweight fibre construction, requires almost no maintenance and has no moving parts. It is also resistant to chemicals and salt water and can be reversed and used as an extractor. The venturi cooler allows air flows of up to 1 lOOi/second at lOOpsi. Also operation is relatively quiet at around 85 decibels.

[0035] The first stage filter cartridge filters harmful bacteria such as E colt, salmonella, Cholera, Rust, giardta, Cryptosporidium and parasites as well as dirt and debris, rust and sediment. This protects the carbon block filter. The carbon block filter removes all chlorine, chemicals, aluminium, chlorine, cadmium, copper, iron, lead, mercury, zinc, pesticides and unpleasant tastes and odours along with heavy metals. The filters are capable of delivering potable water quality. An advantage of the assembly is that no electricity is required and the chiller unit does not use a refrigerant. Water usage of around 15 litres per hour is relatively low. [0036] Figure 5 shows with corresponding numbering a rear elevation view of the cooling unit of figure 5.

[0037] Figure 6 shows an elevation view of an operational schematic layout of the cooling assembly 40 according to an alternative embodiment. According to the embodiment shown the assembly is mounted on a monorail 41 at a mine face 42. Assembly 40 comprises a chiller box 43 similar to the chiller bos described earlier with reference to the schematic layout of figure 1. Chiller box 43 receives a water inlet line 44 and a compressed air inlet line 45 which respectively deliver water and air into chiller box 43, Exiting chiller box 43 is a water line 46 and air line 47. Water line 46 delivers cooled, filtered water to venturi air mover 48. Air line 47 also delivers filtered dried air to venturi 48. A chilled mist of air 49 is delivered to mine face 42 which cools the ambient air at the location of the mine face 42.

[0038] The present invention obviates the disadvantages of the prior art and provides other advantages which are apparent from the description herein. Thus the cooling apparatus is defined according to the particular application or applications and activities to be carried out,

[0039] It will be recognised by persons skilled in the art that numerous variations and modifications may be made to the invention described herein without departing from the overall spirit and scope of the in vention .

Claims

THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS:

1. An assembly for cooling air comprising: a water supply, a source of compressed air , a chiller unit having at least one inlet and a outlet; the chiller unit receiving water from the water supply and compressed air from the source of compressed air, a venturi which receives chilled water from the chiller unit and compressed air from the source of compressed air; the venturi delivering cooled air via a mist nozzle associated wit the venturi into an environment requiring air cooling.

2, An assembly according to claim 1 wherein the source of compressed air deli vers uofiltered compressed air via at least one filter.

3. An assembly according to claim 2 wherein a first of said air filters is a MicronG.Oly filter with an automatic drain.

4. An assembly according to claim 3 wherein a second filter is disposed in series with said first filter.

5. An assembly according to claim 4 wherein the second filter includes activated carbon with an automatic drain.

6. An. assembly according to claim 5 wherein the water source delivers filtered water to the chiller unit.

7. An assembly according to claim 6 further comprising a plurality of water filters;

8. An assembly according to claim 7 wherein the wate filters are selected from a micron filter, a carbon filter and a Doulton Sterasyl Sub Micron filter. 9. An assembly according to claim 8 wherein the chiller unit is a vortex pneumatic chiller which includes at least one inlet and an outlet and which receives water from, the water supply and compressed air from the source of compressed air . I, 0. An assembly according to claim 9 wherein the venturi is an air blower which receives chilled water from the chiller unit and compressed air from the source of compressed air .

I I . An assembly according to claim 12 wherein the venturi air blower delivers said cooled air via a mist /atomiser nozzle.

12. An assembly according to claim 1 1 wherein the nozzle is injected with air and water, associated with the venturi air blower.

13. An assembly according to claim 1:2 wherein further comprising a water flow controller and a heat exchanger vented to the atmosphere. 14. An assembly according to claim ! 3 wherei the venturi cooler assembly includes a venturi air mover fitted wit a spra nozzle mechanism which produces a chilled airflow (mist).

15. An assembly according to claim 14 wherein compressed air and water enter the venturi cooler at ambient temperature thereby providing a chilled airflow spray mist that supresses the air temperature in the vicinity of the air blower as the mist exist the ventun

16 An assembly according to claim 15 wherein the water is fed to the chiller unit via a first water supply line. i 7. An assembly according to claim .16 wherein the compressed air is fed to the chiller unit via a first air supply line. 38. An assembly according to claim 17 wherein the water is fed. to the venturi via a second water supply line.

19. An assembly according to claim 18 wherein the compressed air is fed to the venturi via a second air suppl line.

20. An assembly according to claim 19 wherein the chiller unit has two inlets comprising a water inlet and an air inlet and a water outlet.

21. An assembly according to claim 20 wherein the venturi unit has an air inlet and a water inlet.

22. An assembly according to claim 21 wherein the temperature suppression enabled by the venturi is within the range of 20 degrees C up to 6 metres from the venturi outlet.

23. An assembly according to claim 22 wherein the environment requiring cooling is located in a mine.

24. An assembly for cooling a mine environment the assembly comprising: a chiller bo including a water inlet line and a compressed air inlet line which respectively deliver water and air into the chiller box; a water exit line and air exit line exiting the chiller box; water exit line and air exit line respectively delivering water and air to a venturi air mover: wherein the venturi a chilled mist of air to a mine face thereby cooling the ambient air at the location of the mine face.

25. A venturi for delivery of cooled air in an assembly for cooling air comprising: a water supply, a. source of compressed air, a chiller unit having at least one inlet and an outlet: the chiller unit receiving water from the water supply and compressed air from the source of compressed air, the venturi receiving chilled water from the chiller unit and compressed air from the source of compressed air, wherein, the venturi delivers cooled air via a mist nozzle associated with the venturi when charged with cooled water and compressed air.

26. A method of cooling a mine environment air using an assembly comprising: a water supply, a source of compressed air, a chiller unit having at least one inlet and an outlet; the chiller unit receiving water from the water supply and compressed air from the source of compressed air, a venturi which receives chilled water from the chiller unit and compressed air from the source of compressed air, wherein the ventari delivers cooled air via a mist nozzle associated with the venturi; the method comprising the steps of; a) a connecting a water supply line to a chiller unit b) connecting a compressed air supply to the chiller unit; c) connecting a venturi unit to the compressed air supply d) connecting a water supply line from an outlet in the chiller unit to an inlet to the venturi; e) delivering air from the ventoxi unit chilled by water from the chiller unit.