Patent Publication Number: US-2007094946-A1

Title: Modular industrial equipment facility

Description:
BACKGROUND OF THE INVENTION  
      This invention relates in general to a facility for use with industrial equipment, and in particular to a modular equipment facility for use with heavy industrial equipment such as, for example, air compressor/dryer units.  
      In certain circumstances, the use of prefabricated, modular buildings for purposes such as constructing electrical facilities and residential housing may be an acceptable alternative to more traditional on-site construction methods. The use of individual building modules or units may save time and may reduce the overall complexity associated with some construction projects. However, many modular buildings or structures, although often highly functional, are unacceptable for certain applications because they include multiple modules or units that are connected to one another in a manner that creates a structure or structures that appear to be incomplete, i.e., unfinished, or non-permanent. For example, many modular facilities used for industrial applications include a series of trailers that are connected together or that are simply placed near one another at an equipment site. Facilities of this nature are often undesirable because they are deemed unacceptable by labor unions or because they negatively impact the appearance of the physical environment in which they are located. Thus, there is a need for a modular structure that can be used as an industrial equipment facility and that when complete, has the appearance of a finished, unified, non-modular structure.  
      Certain industrial factories and plants utilize large-scale equipment facilities that operate on a substantially continuous basis so that manufacturing or production can proceed without interruption. However, many industrial equipment facilities, including those that are modular in nature, do not include adequate backup systems or system redundancies that provide for substantially continuous operation in the event that one or more individual components within the system fails. In the absence of adequate safeguards or redundancies, manufacturing operations may be interrupted or may cease if a partial system failure occurs. Furthermore, if manufacturing or production output must be increased or decreased, a rapid expansion or contraction of the equipment facility servicing the factory or plant may become necessary. Existing modular facilities are not typically expandable or reconfigurable without reconstruction of the entire facility. Reconstructing an entire facility to accommodate additional heavy equipment significantly reduces or basically eliminates most of the advantages realized by using a modular structure or system in the first place. Thus, there is a need for a modular industrial equipment facility that provides certain redundancies that assure substantially continuous operation in the event of a partial system failure and that can be reconfigured, i.e., expanded or re-arranged, without significant reconstruction of the entire facility.  
     SUMMARY OF THE INVENTION  
      Deficiencies in and of the prior art are overcome by the present invention, the exemplary embodiment of which provides a modular facility suitable for housing a variety of industrial equipment or devices such as, for example, high-output air compressor/dryers. In accordance with one aspect of the present invention, an industrial system is provided. This system includes a plant for performing one or more industrial processes and a modular industrial equipment facility connected to the plant. The modular equipment facility further includes a plurality of individual modules which may be situated on the end portions of the facility or which may be situated on the inside portion of the facility. Each of the inside or “internal” modules further comprises at least one non-weight bearing external wall and each of the end or “terminal” modules further comprises at least two non-weight bearing external walls. The internal modules and terminal modules may be arranged in a variety of geometric configurations to form a single, integrated structure that has the appearance of a unified, non-modular building.  
      In accordance with another aspect of the present invention, a modular industrial equipment facility is provided. An exemplary embodiment of this facility includes a plurality of pre-assembled, portable modules suitable for use with heavy industrial equipment such as air compressor/dryers or other equipment. The modules may be situated, i.e., placed, on the end portions of the facility or they may be situated on the inside portion of the facility. Each of the inside or “internal” modules further comprises at least one non-weight bearing external wall and each of the end or “terminal” modules further comprises at least two non-weight bearing external walls. The internal modules and terminal modules may be arranged in a variety of geometric configurations to form a single, integrated structure that has the appearance of a unified, non-modular building. Each of the modules (referred to herein as “equipment modules”) modules is typically configured to operate independent of the other equipment modules in the event of a partial system failure. In this embodiment, the terminal modules are typically used to house switchgear, computers, or other electrical equipment while the internal modules are typically used to house air compressor/dryer units. The construction and configuration of both the individual equipment modules and the facility itself creates an industrial facility in which each air compressor/dryer unit operates independent of the other air compressor/dryers in terms of environmental control, i.e., compressor cooling, but that is still fully integrated into the larger facility in terms of compressor air output. The internal environment of the facility itself does not significantly affect or limit the number of air compressor/dryer units that may be added to or removed from the system. Therefore, the output of the industrial equipment facility of this invention may be increased or reduced without the need to significantly reconstruct the entire facility to change internal airflow characteristics. This invention also includes a computerized control system that further includes a local component and a remote component. The local component is typically placed within the equipment facility and provides means by which to both monitor and control the operation of the equipment located within the facility. The remote component is typically placed at a location separate from the main equipment facility and also provides means by which to both monitor and control the operation of the equipment located within the facility.  
      In yet another aspect of this invention, a method for manufacturing, installing and operating a modular industrial equipment facility is provided. This method includes the general steps of: (i) fabricating a plurality of equipment modules for use with heavy industrial equipment such as air compressor/dryer units, wherein the equipment modules further include end or “terminal” modules each having at least two external non-weight bearing walls and inside or “internal” modules each having at least one external non-weight bearing wall; (ii) installing equipment in the equipment modules; (iii) transporting the equipment modules to a predetermined construction site; (iv) arranging the equipment modules to form a single, integrated structure, wherein the single, integrated structure has the appearance of a unified, non-modular building; and (v) connecting the equipment modules to a computerized control system, wherein the control system further comprises a local component and a remote component for monitoring and controlling the operation of the equipment installed in the modules.  
      Additional features and aspects of the present invention will become apparent to those of ordinary skill in the art upon reading and understanding the following detailed description of the exemplary embodiments. As will be appreciated, further embodiments of the invention are possible without departing from the scope and spirit of the invention. For example, the invention may be used to house and operate industrial equipment other than air compressor/dryer units. Accordingly, the drawings and associated descriptions are to be regarded as illustrative and not restrictive in nature. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      The accompanying drawings, which are incorporated into and form a part of the specification, schematically illustrate one or more embodiments of the invention and, together with the general description given above and detailed description of the exemplary embodiments given below, serve to explain the principles of the invention.  
       FIG. 1  is a generalized schematic representation of the industrial system of the present invention showing the factory or plant, the modular industrial equipment facility, the remote monitoring and control component, and the transformers and power source utilized by the equipment facility.  
       FIG. 2  is a side view of one of the equipment modules of the exemplary embodiment showing the ductwork and air compressor/dryer unit contained within the module.  
       FIG. 3  is a side view of one of the equipment modules of the exemplary embodiment showing various electrical components contained within the module.  
       FIG. 4  is a perspective view of an exemplary embodiment of the industrial equipment facility of the present invention under construction showing one of the equipment modules being lowered into position by a crane.  
       FIG. 5  is a perspective view of an exemplary embodiment of the assembled industrial equipment facility of the present invention showing the final placement of the internal modules and the terminal modules relative to one another.  
       FIG. 6  is a cross-sectional side view of an exemplary embodiment of the industrial equipment facility of the present invention showing the placement of air compressor/dryers and associated ductwork within the interior of two equipment modules that are facing one another.  
       FIG. 7  is a side view of the exterior of an exemplary embodiment of the industrial equipment facility of the present invention showing the placement of the internal modules and terminal modules relative to one another.  
       FIG. 8  is a schematic representation of the computerized local and remote components of an exemplary embodiment of the industrial equipment facility of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
      This invention relates to a reconfigurable modular industrial equipment facility for use with a factory, manufacturing plant or other industrial system or operation. An exemplary embodiment of this facility includes a plurality of pre-fabricated, portable equipment modules that are typically transported to and arranged at a predetermined location. These equipment modules further include: a plurality of internal equipment modules (i.e., for placement on the interior or middle portion of the structure), wherein each internal module is configured to operate independently of or in combination with the other internal modules in the event of a partial system failure; and a plurality of terminal modules (i.e., for placement on the end portions of the structure) for use in combination with the plurality of internal modules. When final construction/assembly of the facility of the present invention is complete, the internal modules and terminal modules form a single, integrated structure that has the appearance of a unified, non-modular building. This invention also includes a computerized control system that further comprises a local electronic/digital component that monitors and controls the operation of the various equipment modules and a remote electronic/digital component that is also capable or monitoring and controlling the operation of the equipment modules. This control system facilitates the substantially continuous operation of the industrial equipment facility of this invention. This invention is useful for use with large, heavy duty air compressor/dryers or other equipment, and includes a variety of computer-controlled dampers that allow each air compressor/dryer to operate in a substantially self-contained environment that is largely independent of the internal environment and airflow of the building housing the air compressor/dryers and/or other equipment.  
      Industrial System and Modular Equipment Facility  
      With reference now to the Figures,  FIG. 1  provides a schematic representation of an exemplary industrial system  10 . Industrial system  10  typically includes an industrial plant  20 , such as an automotive plant, which receives pressurized air from a modular industrial equipment facility  30  for operating equipment utilized in the plant. Modular industrial equipment facility  30  may be arranged in any of a variety of geometric configurations, i.e., floor plans, and includes a plurality of equipment modules that further include internal modules  32  and terminal modules  60 . In the exemplary embodiment shown in  FIG. 1 , there are twelve internal modules  32  (six per side and facing one another), ten of which house an air compressor/dryer unit  50  (designated as C 1 -C 10  in  FIG. 1 ) and, optionally, other equipment. Other embodiments of this invention include a greater or lesser number of equipment modules and in some embodiments, at least one of the equipment modules is free of equipment and is used as a “service” module for accessing the equipment in the other modules. The air compressor/dryers  50  direct compressed air into a plurality of air outlets  56 , which are connected to compressed air header  58 , which supplies compressed air to plant  20 . In  FIG. 1 , one of the two internal modules  32  that does not house an air compressor/dryer  50  houses the computer hardware and software included in local component  90 , which monitors and controls the equipment located in facility  30 . Local component  90  is in electrical/digital communication with remote component  100 , which is also capable of monitoring and controlling the equipment located in facility  30 . Control components  90  and  100  are typically in direct or indirect electrical/digital communication with each of the equipment modules. This communication may be wireless. In the exemplary embodiment of  FIG. 1 , there are also four terminal modules  60 . Two of these modules  60  are empty, although as shown in the Figure, compressor/dryer units C 11  and C 12  may be added to equipment facility  30  as needed. The other two terminal modules  60  shown in  FIG. 1  house electric switchgear  80 , which is connected to transformers T 1 -T 4 , which are connected to external power source  105  for providing electric power to industrial equipment facility  30 .  
      Numerous other arrangements of the equipment modules of facility  30  are possible, and it should be noted that  FIG. 1  illustrates only one such configuration. In the configuration shown in  FIG. 1 , the construction and arrangement of the individual equipment modules creates space on the interior of the building that may be used by maintenance workers to access the individual air compressor/dryers  50  and other equipment. Supports  66  provide structural support to each end module and supports  38  provide structural support to each internal module  32  making internal weight bearing walls unnecessary. The dashed lines in  FIG. 1  represent the physical boundaries of each individual module—there are no internal walls present in this embodiment, thereby permitting relatively unrestricted movement within industrial equipment facility  30 .  
      Construction of Equipment Modules  
      In the exemplary embodiment shown in the Figures, equipment modules  32  and  60  have been constructed for use with large, industrial capacity air compressor/air dryer units. Each equipment module is designed to be structurally stable independent of surrounding structures or modules and to accommodate very heavy equipment, if desired. In the exemplary embodiment shown in the Figures, each equipment module housing an air compressor/dryer unit weighs about 45,000 pounds.  FIG. 2  provides a side view of an internal module  32 , and illustrates the placement of an air compressor/air dryer unit  50  within the module.  FIG. 2  also shows the various dampers, ductwork, and other equipment that is typically pre-installed within the module prior to transporting the module to a construction site. As shown in  FIG. 2 , the enclosure portion of internal module  32  includes at least one exterior wall  34 , floor  36 , supports  38 , roof  40 , and aperture  42 . Equipment modules  32  and  60  are typically steel framed and supported over an I-beam framed, reinforced concrete base. Although not shown in the Figures, each equipment module  32  and  60  may be equipped with a monorail four-inch I-beam crane, trolley, and a half-ton hoist for facilitating lifting, placement, or replacement of equipment within the module.  
      The construction specifications of each equipment module may vary based on the site at which facility  30  is being constructed and/or on the equipment being housed and operated in each module. However, in an exemplary embodiment, the exterior walls of each equipment module are sided with 26-gauge “Span-Line  36 ” (Metal Sales Manufacturing Corp.). The exterior walls are metal studded with galvanized metal interior wall panels. The roofing consists of an EPDM membrane roof (60 mil, Firestone) on 3-inch rigid insulation over metal decking, and the insulation is 3.5-inch fiberglass insulation with a R13 rating. The metal deck is 3″×18′ gauge type 3N galvanized steel. The roof slopes 0.25″ per 12″ from a height of 11 ft, 6 inches. The equipment modules  32  and  60  may also include one or more doors  70 . Industrial equipment facility  30  is typically built to meet Zone  1  requirements as defined in the Uniform Building Code of the International Conference of Building Officials. Despite the specific application or equipment used, equipment facility  30  is typically built to be compliant with all relevant local building codes and standards for, but not limited to, building design and construction, steelwork and structural work, pressurized piping and vessels, and electrical wiring. Seismological factors are also typically considered in the construction of both the equipment modules and the facility itself. As will be appreciated by the skilled artisan, other materials may be used for the construction the equipment modules of the present invention.  
      Again with reference to  FIG. 2 , each internal equipment module  32  (or terminal module  60  if used to house an air compressor/dryer  50 ) is equipped with an air handling system that includes ductwork, dampers and computerized controls such that a high volume (e.g., 22,000 CFM) of compressor cooling air may be utilized by each air compressor/dryer  50  regardless of the volume of available air contained within the structure of equipment facility  30 . Although the specifications of each equipment module may vary, in an exemplary embodiment, the air handling system includes: (a) a Total Filtration (28VB10WX06H V) bank inlet filter housing and filter bank  44 ; (b) two Ruskin CDTI-50 low temperature intake air control dampers  48   a  with 110 volt 90 degree actuators; (c) two 15 HP Atlas Copco cooling fans  43 ; (d) a Modicon PLC  53 ; (e) an Atlas Copco compressor/dryer cooling system  51 , which includes an intercooler, an after-cooler, an oil cooler, and a dryer regeneration cooler; (f) discharge air ducts  52   a  and  52   b ; (g) two Ruskin CDTI-50 low temperature recirculation control dampers  48   b  with 110 volt 90 degree actuators; (h) a recirculation air duct  46 ; (i) a Ruskin CDTI-50 low temperature discharge control damper  48   c  with 110 volt 90 degree actuator; (j) a Ruskin CDTI-50 low temperature discharge control damper  48   d  with 24 volt modulating actuator; (k) an outside (ambient) air temperature sensor  41 ; and (l) an internal compressor cooling temperature sensor  45  (see  FIG. 2 ).  
      With reference to  FIGS. 1 and 3 , an exemplary embodiment of this invention includes a variety of industrial grade electrical components that provide power to equipment facility  30  and to the equipment operating therein. In general, the electrical system includes a main power source, a series of transformers, switchgear, power distribution panels, and a series of electrical feeds and lines. More specifically (see  FIG. 1 ), an exemplary embodiment of this invention includes a 13,800 V main switch house  106 , which is connected to four transformers  105 , which are connected to double-ended 480-volt GE AKD switchgear  80 . In this example, switchgear  80  includes two 4000-amp main breakers; four 800-amp individual compressor and/or building power breakers  86 , and one 4000-amp tie breaker. Each set of switchgear  80  includes one 800-amp breaker pre-wired to a GE distribution panel  81  for powering certain auxiliary equipment, such as space heaters, which may be installed in facility  30 , and the single phase 480V/220-110 V single-phase transformer  83 . Transformer  83  is pre-wired to a single-phase panel board  82 . A 600-amp safety disconnect switch  87  may also be included for each air compressor/dryer  50 . Each equipment module  32  and  60  may include pre-installed light switches, duplex receptacles, interior lighting, fluorescent lamps, and electrical wiring. To minimize on-site wiring requirements, “pig tails” or other devices for interconnecting lighting and outlet circuits between modular sections may be provided.  
       FIG. 4  shows modular industrial equipment facility  30  during the assembly process. In this Figure, one of the internal modules  32  is being lowered into place by crane  120 .  FIGS. 5-7  depict the assembled version of modular industrial equipment facility  30 . As is evident from  FIG. 5 , the fully constructed and assembled facility has the appearance of a single, unified, permanent, non-modular structure. As previously discussed, the internal modules  32  typically include a metal frame, a concrete floor  36 , a plurality of supports  38 , and a roof  40 . A single, non-weight bearing exterior wall or panel  34  is attached to the side of internal module  32  that faces the outside environment when industrial equipment facility  30  is assembled. Each terminal module  60  also includes a metal frame, a floor  64 , a plurality of supports  66 , and a roof  68 . Two non-weight bearing exterior panels or walls  62  are attached to the sides of terminal module  60  that face the outside environment when industrial equipment facility  30  is assembled. Terminal modules  60  may be used for housing air compressor/dryers  50  by removing one of the wall panels  62 , cutting an aperture  42  into the panel  62 , and re-attaching the cut panel to the module. Additionally, the roof portion of each equipment module (terminal and internal) typically includes protruding “curbs” that may be used to accommodate discharge air ducts  52   a  and  52   b.    
      With reference to  FIG. 5 , an air intake  72  is included at each end of equipment facility  30  for providing ventilation and cooling air to the interior of the assembled facility. In an exemplary embodiment, each air intake  72  includes a thermostatically controlled motorized damper and a 4′×4′ Total Filtration “v-bank” filter system. In the exemplary embodiment, an individually thermostatically controlled one-quarter HP exhaust fan is installed in discharge duct  52 a above each air compressor/dryer  50  to discharge any excess compressor/motor/piping radiant heat. Relatively cool outside air is then drawn into equipment facility  30  by operation of the air intakes  72 .  
       FIG. 6  provides a cross-sectional side view of two of the internal modules  32  as arranged in an exemplary embodiment of the final, assembled version of industrial equipment facility  30 . As previously indicated, each individual module is typically constructed at a first location and then transported to a second location, in some cases fully loaded with equipment. As discussed, each individual equipment module is constructed to include some, or for certain applications, all of the necessary electrical connections and other connectors that allow that module to be easily connected to the other modules that are included in the completed and functional equipment facility. In an exemplary embodiment, each internal module houses an Atlas Copco ZT275FF air compressor/dryer that is equipped with an air dryer having preinstalled interconnecting piping that includes  3 -way bypass piping. In the exemplary embodiment, each equipment module that houses an air compressor/dryer unit includes a  4 -inch Victaulic air-piping riser  56  connected to a 10-inch, Schedule  40  air header  58  with flanges on each end for quick and easy interconnection with the other equipment modules. Additionally, prior to shipping, the condensate drain discharges of each air compressor/dryer  50  are connected by way of tubing to a 3-inch PVC manifold pipe  59 , 10-feet in length (see  FIG. 6 ), which is installed over each air compressor/dryer  50  and permits easy interconnection with the condensate drain discharges of the other equipment modules.  
      The overall size of the final structure may be changed, or the geometric configuration altered, by removing individual modules or groups of modules, by adding modules, or by rearranging the modules already in use. Advantageously, the significant weight of each module allows the final facility to be assembled in most cases without actually connecting, to any significant degree in terms of structure, the individual modules to one another. Thus, essentially, the final facility is a group of freestanding equipment modules that have been placed close to one another. Once the facility is assembled, a roofing material may be used to seal seams between the roof portions  40  and  68  to prevent the elements, especially water, from entering the industrial equipment facility  30 . Metal siding filler pieces may also be used to cover seams between the exterior wall panels  34 .  
      Equipment Facility Control System (Hardware and Software)  
      With reference to  FIGS. 1 and 8 , the industrial equipment located in facility  30  is monitored and controlled by a computerized system that includes an on-site local component  90  and a separate remote component  100 . This computerized system allows the equipment in facility  30  to operate in a substantially autonomous or automated manner and typically very little human intervention is involved once the facility is brought on-line. The hardware and software included in this computerized system allows the equipment in each of the individual modules to function both in combination with and independent of the equipment in the other modules, and helps assure that the failure of equipment in one or more modules does not negatively impact the operation and output of the entire system. As shown in  FIG. 8 , an exemplary embodiment of local component  90  includes custom computer software for monitoring and controlling the equipment in the modules, a wireless router/switch  91 , a system control computer  92 , a power monitor damper control computer  93 , a security camera computer  94 , an ION® meter bank  95  for measuring power usage, and a bank of security cameras  96 . Local component  90  is in electronic/digital communication with remote component  100 . Remote component  100  typically includes custom computer software for monitoring and controlling the equipment in the modules, a remote access software component  101 , a data connection  102 , a remote access device or service (e.g., cell phone, Internet, or other means)  103 , and a remote server  104 . The ManagAIR® system (available from Ohio Transmission Corporation; Columbus, Ohio) is an example of a software-based system that may be used for local component  90 , and the MonitAIR® system (also available from Ohio Transmission Corporation; Columbus, Ohio) is an example of a software-based system that may be used for remote component  100 . These systems may be used to generate and send alarms and various reports by way of e-mail or other electronic/digital communications means. Both of these systems are useful for monitoring and controlling the operation of a compressed air facility. However, as will be appreciated by those skilled in the art, other custom or customizable software-based systems may be used with the present invention.  
      In an exemplary embodiment, each air compressor/dryer  50  contains a wireless communication device that provides at least two communications ports. A first port is used to connect to the compressor/dryer&#39;s Elektronikon (Atlas Copco) control system and power metering equipment located in the compressor/dryer disconnect. A second data port is used for connection to a Modicon programmable logic controller (PLC) that is added to each air compressor/dryer  50 . In general terms, programmable logic controllers are known computerized devices typically used for automating industrial processes. These devices are microprocessor-based and include either modular or integral input/ouput circuitry that monitors the status of field connected sensor inputs and controls attached devices (motor starters, solenoids, actuators, pilot lights/displays, speed drives, valves, etc.) according to a user-created program stored in battery-backed memory. The functionality of a PLC may include typical relay control, sophisticated motion control, process control, distributed control, and complex networking. The PLCs used with the present invention automate the process of regulating each air compressor/dryer&#39;s cooling air temperature in response to changes in ambient conditions and/or compressor heat loads. In this embodiment, the ManagAIR® system requests data from all the air compressor/dryers at predetermined intervals. These data include information such as current operational status; operating parameters such as pressures, temperatures and vibration levels; power information, warning and alarm status for each parameter, as well as service information. The ManagAIR® system analyzes this information and performs various operations based on these results. By communicating with the PLC used with each air compressor/dryer  50 , the ManagAIR® system may be used to: (i) log data for trending and diagnostics; (ii) start or stop machines based on demand; (iii) load and unload machines based on demand; (iv) adjust compressor sequence; (v) analyze data for predictive intervention; (vi) calculate energy efficiency; (vii) provide alarms by way of alphanumeric page; and (viii) provide e-mail and/or facsimile communications.  
      In addition to power monitoring equipment, which is typically provided for each air compressor/dryer  50 , in an exemplary embodiment, four ION power-metering devices are located in switchgear  80 . These devices are connected by an Ethernet cable to router  91 . A second complete computer system running ION Windows based software monitors all information from the ION power metering equipment. Also installed on this computer is software designed to monitor and control the Modicon PLCs located in each air compressor/dryer  50 . Communications between this computer and the PLCs are typically carried out over an encrypted wireless Ethernet connection. This computer also serves as a backup to the computer running the ManagAIR® software or other software.  
      In the exemplary embodiment, a third computer is also located at the facility site for the purpose of video surveillance. This surveillance system is a digital video recorder (DVR) system that includes a Windows-based computer that incorporates specialized video hardware and software. Attached to the computer is a plurality of cameras  96  located inside and outside of the building. Outdoor fixed cameras and indoor pan and tilt cameras are connected to the computer with standard video/power wiring. A portable wireless camera is also located inside industrial equipment facility  30 . The DVR system is equipped to record all motion detected by the cameras for the purpose of security. The system also allows visual inspections of the site to be performed remotely by way of the Internet or other remote means.  
      Equipment Facility Operation (Module Micro-environment)  
      Due to the unique modular construction of industrial equipment facility  30 , the operation of the equipment housed in each module, i.e., each air compressor/dryer  50 , is not significantly limited by the volume of air that can be drawn into the integrated structure itself. Because each air compressor/dryer  50  draws compressor cooling air and compressor intake air from the environment outside the facility and not from inside the facility, the operation of each individual air compressor/dryer  50  does not restrict or negatively impact the operation of the other air compressor/dryers  50 , nor does it limit number of air compressor/dryers that may be included in facility  30 . The air handling on the interior of facility  30  is used to dissipate radiant heat and is not used as a source of compressor cooling air or compressor intake air. Consequently, additional equipment modules and air compressor/dryers may be added to or removed from industrial equipment facility  30  without necessitating reconstruction of the entire building.  
      With reference to the exemplary embodiment of the present invention shown in  FIGS. 2 and 6 , each internal module  32  (or terminal module  60  if an air compressor/dryer  50  has been installed therein) includes an aperture  42  in exterior wall  34 . Inlet filter housing and filter bank  44  are connected to aperture  42 , and air from the outside environment is drawn into each air compressor/dryer  50  through aperture  42 . Air that is used by the components of air compressor/dryer cooling system  51 , i.e., the intercooler, after cooler, oil cooler, and dryer regeneration cooler, is drawn into air compressor/dryer  50  though filter housing and filter bank  44  by compressor cooling fans  43 . Compressor intake air is also drawn into the air compressor portion of compressor/dyer unit  50  through aperture  42 , but bypasses the filter bank and enters compressor air intake hose  110 , which is attached to roof  36  by support brackets  112 . Compressor intake hose  110  is attached to the air compressor portion of compressor/dyer unit  50  at housing  111 .  
      Each equipment module that contains an air compressor/dryer  50  includes a computerized system that operates dampers  48   a - 48   d  to control the intake, exhaust and recirculation of the cooling air utilized by the air compressor/dryer. This computerized system allows cooling air to be re-circulated to the extent necessary (based on temperature) to maintain the proper operating environment for the various coolers, and consequently, for each air compressor/dryer  50 . Cooling air is not drawn into the air compressor/dryers from the inside of the building that houses the air compressor/dryers; thus, the internal environment and internal air handling capacity of industrial equipment facility  30  does not limit the number of air compressor/dryers that may be included in or added to any particular facility. The exemplary embodiment of the present invention does typically include at least one filtered vent  72  on each end of the industrial equipment facility  30  for supplying cooling air to disperse the radiant heat generated by the air compressor/dryers; however, the primary source of cooling air is the environment external to industrial equipment facility  30 .  
      Regarding cooling air intake, exhaust and recirculation, Modicon PLC  53  monitors external temperature sensor  41 , mixed temperature sensor  45 , and the operating status of each air compressor/dryer  50  through an auxiliary motor starter contactor and controls the relative positions of the system&#39;s dampers and fans. When the temperature outside industrial equipment facility  30  is at or above 50° F., and an air compressor/dryer  50  is operating: Modicon PLC  53  opens the inlet control dampers  48   a , closes the recirculation dampers  48   b , and opens the discharge control dampers  48   c  and  48   d.  When the air compressor/dryer  50  begins running, 22,000 CFM of cooling air is drawn into the air compressor/dryer through the inlet filter housing and filter bank  44 . This air is then directed through the inlet air control dampers  48   a  into the air compressor/dryer&#39;s enclosure, up through the air compressor/dryer coolers  51  (which heats the cooling air), out of the air compressor/dryer enclosure into the discharge duct  52   a,  out through the two Modicon PLC-controlled discharge dampers  48   c  and  48   d,  and finally through discharge gooseneck duct  52   b  to the outside environment. The recirculation control dampers  48   b  remain closed during this operational mode. This procedure allows for a “once through” cooling air circuit which is preferable when air temperatures are relatively warm (i.e., above 50° F).  
      If external air temperature sensor  41 , which is connected to or in communication with Modicon PLC  53 , measures an outside temperature below 50° F., 22,000 CFM of cooling air is drawn into the air compressor/dryer through the inlet filter housing and filter bank  44 . This air is then directed through the inlet air control dampers  48   a  (opened by Modicon PLC  53 ) into the air compressor/dryer enclosure, up through the air compressor/dryer coolers  51  (which heats up the cooling air), out of the air compressor/dryer enclosure, and into discharge duct  52   a . At this point Modicon PLC  53 , which is measuring the mixed cooling air temperature with temperature sensor  45 , opens the recirculation damper  48   b  to allow warm air to recirculate and mix with the cold outside air in the inlet filter housing and filter bank  44 . The Modicon PLC  53  will also turn off one of the two cooling fans  43  and close one of the two intake control dampers  48   a  to reduce the cooling airflow and save energy. If the mixed cooling air temperature drops below 45° F., the Modicon PLC  53  closes the discharge control damper  48   c  and begins to modulate the discharge control damper  48   d  to maintain a mixed cooling air temperature between 45° F. and 55° F.; thereby preventing freeze-ups and/or air compressor/dryer malfinction. If compressor/dryer  50  is sensed as not operating (i.e., is not on), the Modicon PLC  53  closes the inlet control dampers  48   a  and the discharge control dampers  48   c  and  48   d . A heater inside of air compressor/dryer enclosure is then turned on to prevent air compressor/dryer coolers  51  from being “cold soaked” by cold outside air and ready for startup. In the exemplary embodiment, the Modicon PLC  53  used with each air compressor/dryer  50  is connected by way of an encrypted wireless connection to software running on the backup PC. This software allows for remote adjustment of temperature set points in each Modicon PLC  53  as well as full manual control and override capabilities.  
      Advantages of the present invention include, but are not limited to, the following: (i) the operation or malfunction of one compressor/dryer unit does not affect any of the other compressor dryer units, thereby substantially improving overall system reliability; (ii) pre-installing the ventilation and recirculation subsystem greatly accelerates the overall on-site system installation and also allows for prototyping and testing the system&#39;s operation prior to on-site installation and startup, thereby ensuring proper performance; (iii) starting or stopping any individual unit in the system does not adversely affect operation of the entire the system; (iv) adding or removing equipment modules requires little or no building redesign or modification, thereby reducing costs and complications associated with changing the size and/or capacity of a system (i.e., adding or removing compressor/dryer units) after the initial installation; (v) the number of air-cooled compressor units or other industrial equipment installed in a single building/facility can be substantially greater than current facilities, thereby allowing for much larger system capacities with less complicated and more flexible ventilation systems; (vi) significant energy savings is realized due to the recovery of the hot discharge air in winter and due to the shutting off of one of the  15  HP fans under certain operating conditions; and (vii) remote adjustments of the ventilation system are possible, as is full manual control when needed. Additionally, the facility has the appearance of an actual, integrated structure or building and not a trailer or series of trailers and can be expanded or contracted by adding or removing individual modules to or from the existing structure without reconstructing the entire facility.  
      While the present invention has been illustrated by the description of exemplary embodiments thereof, and while the embodiments have been described in certain detail, it is not the intention of the Applicant to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art. Therefore, the invention in its broader aspects is not limited to any of the specific details, representative devices and methods, and/or illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the spirit or scope of the applicant&#39;s general inventive concept.