Abstract:
A pre-manufactured natural gas delivery station is presented to a client that filters, measures, controls, pre-heats, pressure reduces, odorizes, and provides communication, provides excess power, and provides excess heat for a host site. The design is pre-approved by supply pipeline, end users and regulatory bodies. The final configuration is welded, assembled, wired, painted, tagged, and tested, at a factory site and then shipped to an installation site in accordance with customer&#39;s requirements. The station is commissioned, operators are trained and a three volume project DATA book is installed in the control room for documentation. The pre-manufactured natural gas delivery station can include a high pressure gas metering room and regulating room that can be selectively coupled to other prefabricated modular rooms or modules. Preferably, the other prefabricated modules include an odorant room, a heating room, an energy generation room and an electrical control and communications room. The equipment and control systems for each room is preinstalled and secured to the building structure in each of the different modules at the factory site. The energy generation room and the electrical control room allows the gas metering station to be operated by electrical energy from a local utility line or from an internal generator that is fueled by the gas being metered.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention generally relates to portable pre-manufactured modular natural gas delivery stations. More specifically, the present invention relates to prefabricating modular units that are combined to form a pre-manufactured natural gas delivery station at a power plant, gas distribution company or an industrial site. This invention utilizes separate stand alone or combined rooms. There is a high pressure gas metering and regulating room, an odorization room, a glycol heater room, a data acquisition and control room and a co-generation room. This entire code compliant and pipeline approved facility can be placed upon an ⅛ of an acre and cost less than half of the cost of previous facilities of similar size. 
     2. Background Information 
     Natural gas is a widely used source of energy throughout the world. For example natural gas is widely utilized in many countries for power generation, heating and/or cooking. Natural gas is often transported via high pressure (e.g., 1440 psig) natural gas pipelines to various gas delivery stations or distribution points around a country. The gas from the natural gas pipeline is typically measured, odorized and controlled by a utility company or a natural gas distributor, and then the gas is distributed by the utility company or distributor to the customers at pressures as low as 7″ of water column. In addition, the gas must be preheated prior to pressure reduction. There is a specific reason for this pre-heat. When decompression takes place heat loss occurs at a rate of seven degrees F. of heat loss for each 100 psi of decompression. For example, gas delivered at 35 degrees F. and 600 psig would drop in temperature to 0 degrees F. If the pressure were dropped to 100 psig and no preheat was applied this could cause equipment failures or frost heaves in earth around a buried pipeline. 
     Deregulation of the Energy Sector and Clean Air Policies have created an unprecedented demand for new interconnects to be installed within the Natural Gas Transmission systems throughout the world. The vast amount of new interconnects, both in the inner cities and remote rural locations, and limited resources of various companies have created a need for a complete, portable, low profile, quiet, code compliant, insurance compliant, environmentally friendly, pre-approved solution to the complex interconnection to a gas transmission pipeline. 
     At each of these distribution points, typically there is a natural gas city gate station or natural gas delivery station that is the delivery point of natural gas from the pipeline to its customers. In the past, the gas companies utilized in-house expertise for engineering and project management of the new city gate stations. However, deregulation and clean air regulations have created situations that have resulted in shortage of in house expertise. In particular, deregulation has forced many companies to downsize their staffs to a point where much of the in-house talent is gone. Moreover, traditional college curriculums do not educate new graduates adequately in the uniqueness of compressible fluid dynamics, and other properties of natural gas. Demand in the use of natural gas has created an unprecedented demand for new interconnects. Accordingly, new companies have entered the marketplace who are unfamiliar with the engineering, and regulatory requirements of the natural gas industry. 
     In the past, these natural gas city gate stations were typically constructed completely on site from scratch. Each of the natural gas city gate stations tend to be slightly different depending upon the utilities needs and/or desires and the pipeline company needs and/or desires. However, most natural gas city gate stations typically have certain common equipment that is needed to accomplish the desired tasks of metering, regulating, preheating, odorizing and controlling of the high pressure gas pipelines. These natural gas city gate stations often include a metering building, a regulating building, a data acquisition control building, an odorant building and a heating area. Because these natural gas metering stations are typically constructed completely on site from scratch, they often are quite expensive and time consuming to construct. 
     Moreover, these natural gas city gate stations were constructed of several separated buildings. This was mainly due to the fact that the pipeline company would own certain equipment and buildings and the utility company and/or distributor would own certain other equipment and buildings. 
     Construction of these natural gas city gate stations can be complicated by the fact that sometimes these stations are located in exclusive neighborhoods that are sensitive to noise, odor, hazardous waste, air quality and aesthetics or in remote rural areas. This increases the difficulty in economically and rapidly constructing natural gas city gate station. In addition, natural gas city gate stations that are located in rural areas are more frequently prone to power outages and are difficult to service during power outages. 
     Design and construction of these natural gas city gate stations can be further complicated by the fact that a supplier and end user must conceptualize this new interconnect, develop operating agreements, develop lines of responsibility, locate land, secure permitting, for a large, noisy, visible and smelly site. 
     In view of the above, there exists a need for a method of prefabricating modular units for forming a natural gas delivery station, which overcomes the above mentioned problems in the prior art. Moreover, there exists a need for a natural gas delivery station that can produce its own electrical energy. This invention addresses these needs in the prior art as well as other needs, which will become apparent to those skilled in the art from this disclosure. 
     SUMMARY OF THE INVENTION 
     One object of the present invention is to create a pre-manufactured, portable, modular, single building, innovative approach that combines filtering, metering, preheating, pressure regulation, flow control, odorization, electrical power distribution, electronic control, gas analysis, backup power, can provide excess power to a host site, and can provide excess heat to a host site. The invention illustrates a portable pre-manufactured single building innovative approach. 
     One object of the present invention is to provide a pre-manufactured natural gas delivery station that can be manufactured in accordance with customer specifications and then shipped to the installation site as a completed unit. 
     Another object of the present invention is to provide a pre-manufacturcd natural gas delivery station that reduces the on-site installation time and costs. 
     Another object of the present invention is to provide a natural gas delivery station that is more economical to manufacture than prior art natural gas delivery stations. 
     Still another object of the present invention is to provide a pre-manufactured natural gas delivery station that can generate its own electricity from the gas being metered therethrough. 
     Still another object of the present invention is to provide pre-manufactured natural gas delivery station that can operate either utilizing electrical energy from an electrical power line or from the gas being metered therethrough. 
     Another object of this invention is to implement a project approach that allows for a pre-approval from pipelines, the Federal Energy Regulatory Commission (FERC), end users, local, county and state regulatory bodies. The present invention utilizes a pre-manufactured or standardized approach in which the plans, documentation, and specifications for all of the rooms or modules can be quickly submitted to and approved by the necessary parties. This allows for a fast pre-approval of the natural gas delivery from pipelines, the Federal Energy Regulatory Commission (FERC), end users, local, county and state regulatory bodies. 
     Another object is to eliminate large in line heaters which use thousands of gallons of ethylene glycol, and which are low efficiency, noisy, and difficult maintenance. The present invention accomplishes this objective by using remote heaters that are located within a specially designed building. Preferably, low reservoir propylene glycol heaters are used along with shell and tube heat exchangers. This eliminates the need for large in line heaters. By placing the heaters inside a building, the noise to the surrounding area is reduced. Moreover, emissions are contained within the building and can be filtered. 
     Another object of the invention is to decrease the visibility of this facility. The low profile design decreases the visibility of this facility and thus, can be more readily concealed from the surrounding community. 
     Another object of the invention is to decrease the noise of this facility. Noise attenuation, acoustical panels, and low noise heaters are used in the buildings to decrease the noise of this facility to less than 40 DBA at the property lines. 
     Another object of the invention is to decrease site size requirements. In the prior art facilities, the various buildings are separated from each other. The single building station of the present invention decreases land use to approximately ⅛ of an acre. 
     Another object of the invention is to eliminate odors and noise during operation of the natural gas delivery station. By building the natural gas delivery station at the factory site, certain construction techniques can be used which are not suitable for construction at the installation site. For example, special welding techniques can be used that prevent odors leaking out of the piping during operation of the natural gas delivery station. 
     Another object of the invention establishes a cost sharing mechanism between pipelines and end users. The benefit of such a design can make cost sharing very acceptable. 
     Another object of the invention is to decrease project cost. The combined facility can be one half the cost of the traditional pipeline interconnects. 
     Another object of the invention is to utilize approved designs in measurement, hazardous area classifications and equipment selection that will simplified approval from pipelines, regulators and insurance inspectors. American Gas Association (AGA) approved designs in measurement, hazardous area classifications and equipment selection can be used in the natural gas delivery station, which simplified approval from pipelines, regulators and insurance inspectors. 
     Another object of the invention is to develop a solution that helps expand the use of gas and is repeatable. The invention helps expand the use of gas with ease of new interconnects and seems exceptionally attractive for new power plant feeds as well as new franchises. 
     Another object of the invention is to be able to use each room or module of the present invention independently or together. Each room of the design can stand alone. For example the odorant room can serve as a mainline odorizer. The heater room can be utilized to replace inline heaters. 
     Another object of the invention is to use the invention in other applications relating to liquefied natural gas, or propane systems. The present invention has other uses in the energy business. The invention can be put on a site with liquefied natural gas storage tanks or propane storage tanks and provide a complete system for measuring, heating, odorizing, controlling, the process for a remote feed. 
     This invention is intended to provided a cost effective, environmentally benign, low visibility, small footprint, alternative to traditional pipeline interconnects. These traditional natural gas interconnects from the high pressure pipeline facilities traditionally have consisted of as many as five buildings and covered several acres of land. 
     In accordance with one aspect of the present invention, a method of pre-manufacturing a natural gas delivery station is carried out by performing the following steps: prefabricating at a factory site a high pressure gas metering and regulating room having high pressure gas piping with a gas inlet adapted to be coupled to a first gas transmission line and a gas outlet adapted to be coupled to a gas distribution line; prefabricating at the factory site a predetermined set of modular buildings that are configured to be coupled to the high pressure gas metering and regulating room; combining at the factory site the high pressure the gas metering and regulating room with at least one of the predetermined set of modular buildings at the factory site to form a customer selected gas delivery station; and shipping the customer selected gas delivery station from the factory site to a customer installation site, which is remote from the factory site. 
     In accordance with this method of the present invention, the customer can select predetermined set of modular buildings or rooms, which preferably includes a gas metering and regulating room, an odorant room, a boiler room, a energy generation room and an electrical and control room. Of course, other modules or rooms can be included in the predetermined set of modular buildings from which the customer can create the high pressure gas delivery station. Moreover, it is possible that a room or module can be constructed which is not one of the prefabricated rooms or modules. In other words, the customer can have a high pressure gas delivery station that includes both the prefabricated rooms or modules and completely customized rooms or modules. The prefabricated rooms or modules are typically outfitted such that certain basic equipment is built into all similar prefabricated rooms or modules. Of course, additional custom features can be added to the basic pre-manufactured rooms or modules at the factory site as needed and/or desired by the customer. 
     In accordance with another aspect of the present invention, a gas delivery station is provided with co-generation of electrical energy. Basically, the gas delivery station has a high pressure gas metering and regulating room, a generation room and a dual power control unit. The high pressure gas metering and regulating room has high pressure gas piping with a gas inlet adapted to be coupled to a first gas transmission line and a gas outlet adapted to be coupled to a second gas distribution line. The high pressure gas piping has a high pressure gas metering unit and gas regulating equipment and a gas heat exchanger coupled between the gas inlet and the gas outlet. The generation room is provided with a gas operated generator having a gas conduit fluidly coupled to the high pressure gas piping so that the generator is powered by the natural gas being metered. The dual power control unit is electrically coupled to the gas operated generator to receive electrical energy therefrom and configure to be electrically coupled to an electrical utility line for receiving electrical energy therefrom. 
     The gas delivery station of this aspect of the present invention further includes an odorant room, a boiler room and an electrical control room. These rooms are constructed as module that are fixedly coupled together to form a single integrated building. 
     These and other objects, features, aspects and advantages of the present invention will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses a preferred embodiment of the present invention. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Referring now to the attached drawings which form a part of this original disclosure: 
     FIG. 1 is a perspective view of a pre-manufactured gas delivery station installed at an installation site in accordance with the present invention; 
     FIG. 2 is a top plan view of the pre-manufactured gas delivery station illustrated in FIG. 1 in accordance with the present invention; 
     FIG. 3 is an enlarged, top plan view of the high pressure gas metering and regulating module or room illustrated in FIGS. 1 and 2 in accordance with the present invention; 
     FIG. 4 is an enlarged, top plan view of the odorant module or room illustrated in FIGS. 1 and 2 in accordance with the present invention; 
     FIG. 5 is an enlarged, top plan view of the gas heating module or room illustrated in FIGS. 1 and 2 in accordance with the present invention; 
     FIG. 6 is an enlarged, top plan view of the energy generation module or room illustrated in FIGS. 1 and 2 in accordance with the present invention; 
     FIG. 7 is an enlarged, top plan view of an electrical control module or room illustrated in FIGS. 1 and 2 in accordance with the present invention; 
     FIG. 8 is a schematic diagram for the pre-manufactured gas delivery station illustrated in FIGS. 1 and 2 in accordance with the present invention; and 
     FIG. 9 is an alternate schematic diagram for the pre-manufactured gas delivery station illustrated in accordance with the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring initially to FIGS. 1 and 2, a pre-manufactured gas delivery station  10  is illustrated in accordance with the present invention. Pre-manufactured gas delivery station  10  basically has five modules or modular rooms  11 - 15  that can be selectively coupled together at a factory site to form a single prefabricated building. 
     The natural gas delivery station  10  is low profile, odorless, quiet, and small. The pre-manufactured natural gas delivery station  10  can be constructed to be a single building that is 12 feet wide and 55 to 75 feet long. Preferably, the five modules or rooms  11 - 15  include a high pressure gas metering and regulating module or room  11 , an odorant module or room  12 , a gas heating module or room  13 , an energy generation module or room  14  and an electrical control module or room  15 . Of course, it will be apparent to those skilled in the art from this disclosure that additional modules can be utilized. 
     Documentation is prepared prior to manufacturing the customer selection of modules or rooms  11 - 15  and the individual pieces of equipment contained therein. This documentation also serves as submittal to Federal Energy Regulatory personnel and to the pipeline, end user, insurance inspector, and town building officials for pre-approval. This documentation can be quickly generated since each of the modules or rooms  11 - 15  will be completely and separately documented. Thus, the documentation for the gas delivery station  10  can be generated by combining the documentation of each version of the modules or rooms  11 - 15  that are selected. Because the same basic modules are used with each gas delivery station, the documentation will be familiar to the various individuals purchasing or approving the gas delivery station. 
     Each of the building rooms or modules  11 - 15  are designed to be prefabricated as separate rooms, which are assembled as a single prefabricated at a factory site and then transported to an installation site as seen in FIG.  1 . In other words, each of the rooms or modules  11 - 15  is designed as a stand-alone unit that can be coupled in any order and/or combination with the other modules. 
     Generally speaking, prefabricating at a factory site, rooms  11 - 15  with standard equipment, carries out the method of prefabricating of gas delivery station  10  in accordance with the present invention. The basic building of gas delivery station  10  is the high pressure gas metering and regulating room  11 . Several different versions of the high pressure gas metering and regulating room  11  can be prefabricated at the factory site to accommodate different requirements. For example, FIG. 8 illustrates one embodiment of the gas delivery station  10 , and FIG. 9 illustrates another embodiment of the gas delivery station  10 . In addition to the basic gas metering and regulating room  11 , a predetermined set of modular rooms  12 - 15  is prefabricated at the factory site. These modular rooms  12 - 15  are configured to be coupled to the high pressure gas metering and regulating room  11  and each other to form a single unit. Preferably, these rooms  11 - 15  are combined together at the factory site in accordance with the customer&#39;s request. The rooms  11 - 15  can be fastened together utilizing conventional construction techniques, which are well known to those skilled in concrete construction. 
     While FIGS. 1 and 2 illustrate a gas delivery station  10  with all five modules or rooms  11 - 15 , it will be apparent to those skilled in the art from this disclosure that any combination of rooms can be combine together to meet the customer&#39;s requirements. In other words, the high pressure gas metering and regulating room  11  can be combined with one or more of the modular rooms from the predetermined set of modular rooms  12 - 15  at the factory site to form a customer selected pre-manufactured gas delivery station. Moreover, the order or arrangement of the rooms  12 - 15  can be changed as required by the customer(s). Alternatively, two or more predetermined set of modular rooms  12 - 15  are combined together to form a building that can be used with a preexisting delivery station. Once the selected prefabricated rooms are fastened together at the factory to form a single building, the pre-manufactured gas delivery station selected by the customer is then shipped from the factory site to a customer installation site, which is remote from the factory site. Accordingly, the pre-manufactured gas delivery station  10  is easily installed at the installation site in considerably less time and with considerably less expense. 
     In the preferred embodiment, the customer is basically selecting one or more of the prefabricated modular buildings  11 - 15  which, as mentioned above, preferably includes high pressure gas metering and regulating room  11 , odorant room  12 , boiler room  13 , energy generation room  14  and electrical control room  15 . Of course, other modules or rooms can be included in the predetermined set of modular buildings from which the customer can create a pre-manufactured gas delivery station  10 . Moreover, it is possible that in addition to the prefabricated rooms  11 - 15 , the customer can request a custom build room or module, which is not one of the prefabricated rooms or modules. In other words, the customer can have a pre-manufactured gas delivery station  10  that includes both the prefabricated rooms or modules and completely customized rooms or modules. The prefabricated rooms or modules  11 - 15  are typically outfitted with certain basic equipment that is built into all similar prefabricated rooms or modules  11 - 15  as discussed below. Of course, additional custom features can be added to the basic or standard equipment of prefabricated rooms or modules  11 - 15  at the factory site or the installation site as needed and/or desired by the customer. 
     In accordance with another aspect of the present invention, pre-manufactured gas delivery station  10  is provided with energy generation room  14  so that pre-manufactured gas delivery station  10  can produce its own electrical energy. Basically, when station  10  has at least both the high pressure gas metering and regulating room  11  and the energy generation room  14 , the station  10  will be able to operate either from an outside source of electrical energy or create its own electrical energy as explained below. 
     Preferably, the pre-manufactured gas delivery station  10  is installed on two reinforced concrete grade beams at the installation site. When the rooms or modules  11 - 15  are joined together, the resulting station  10  will be a complete integral waterproof building structure. The rooms or modules  11 - 15  can be fixedly coupled together using mortar or other fastening techniques such that station  10  can be shipped as a single building with multiple rooms. Each building module  11 - 15  is preferably of room-size dimensions such that it can easily contain the necessary and/or desired control system equipment, and personnel can easily move about therein. Preferably, the overall dimension of the assembled station  10  is approximately 55 to 75 feet long and 12 feet wide. While the final assembly of pre-manufactured gas delivery station  10  occurs at the factory site, it will be apparent to those skilled in the art from this disclosure that the various modules and/or equipment can be manufactured at other locations and transported to the factory site for final installation and assembly of station  10  before being shipped to the installation site. 
     At the factory site, all of the standard equipment, the electrical wiring and the piping are installed into each of the building modules  11 - 15 . All of the equipment is preferably bolted down or otherwise secured within its particular building module or room so that it will remain at a fixed location therein during transportation. The various pieces of equipment that are installed in each of the modular rooms  11 - 15  are interwired and/or piped with one another at the factory site to form the pre-manufactured gas delivery station  10 . 
     Preferably, all of the equipment installed in the building modules  11 - 15  is thoroughly tested at the factory site. This testing preferably includes individually testing all of the equipment as well as testing the equipment after the equipment is interconnected so as to operate as a single unit. All major and, if necessary, minor adjustments are preferably made at the factory so that minimal amount of adjustments will be needed at the installation site. As a result of prefabricating and pre-testing of the control system equipment, the pre-manufactured gas delivery station  10  is easily installed at the installation site in considerably less time and with considerably less expense. 
     As shown in FIGS.  1 - 3 , the high pressure gas metering and regulating room  11  is preferably fabricated of concrete, which is designed to be fire-rated and gas impermeable in accordance with the industries&#39; safety regulatory requirements. The phrase “fire-rated and gas impermeable” as used herein to refer to the construction of the walls of gas delivery station  10  means the existing fire rating requirements and gas impermeable rating requirements for walls of a gas metering station at the time of construction thereof. 
     As shown in FIGS.  1 - 3 , high pressure gas metering and regulating room  11  basically has a flat base  20 , a pair of flat end walls  21 , a pair of flat side walls  22  and an angled roof  23 , which together form a three-dimensional, rectangular building module. As mentioned above, high pressure gas metering and regulating room  11  can be fixedly coupled to the other rooms or modules  12 - 15  to form a single building. When two or more of the rooms or modules  11 - 15  are coupled together, the bases, the side walls and the roofs of the rooms or modules  11 - 15  are contiguous with the adjacent rooms or modules regardless of their order. Accordingly, high pressure gas metering and regulating room  11  is a three-dimensional module having substantially the same cross-sectional configuration as the other rooms or modules such that it can be mated with the other rooms or modules. In the preferred embodiment, this is accomplished by having end walls  21  of high pressure gas metering and regulating room  11  being substantially the same size and shape as the end walls of the other rooms or modules  12 - 15 . 
     In the preferred embodiment, one of the end walls  21  is provided with a pair of doors  24  for accessing the interior of high pressure gas metering and regulating room  11 . Doors  24  can be optionally provided with panic hardware if needed and/or desired. The other end wall  21  is designed to mate with any one of the other modules  12 - 15 . The end wall  21  with doors  24  also has a pipe inlet opening  25  and a pipe outlet opening  26  so that the gas to be metered and/or regulated can enter and exit high pressure gas metering and regulating room  11 . The side walls  22  can be provided with vents  27  for allowing fresh air to circulate therein. One of the side walls  22  preferably also has one or more access openings  28  for running piping and/or wires into high pressure gas metering and regulating room  11  from the other modules  12 - 15 . The various electrical components and/or lighting fixtures  29  are mounted on the concrete end walls  21  and/or side walls  22  and/or roof  23  of high pressure gas metering and regulating room  11  in a conventional manner as needed and/or desired. 
     High pressure gas metering and regulating room  11  is preferably equipped with conventional metering and regulating equipment. Since such metering and regulating equipment is well known within the art, such metering and regulating equipment will not be discussed or illustrated in detail herein except for as it relates to the uniqueness of the present invention. 
     As seen in FIG. 2, a high pressure gas piping system  30  is installed within high pressure gas metering and regulating room  11  for metering and regulating gas such as natural gas from a first gas pipeline A to a second gas pipeline B, as seen in FIG.  1 . More specifically, high pressure gas piping system  30  includes inlet piping  31  fixedly coupled to first gas pipeline, a high pressure gas metering unit  32 , a flow control valve  33 , a heat exchanger  34 , a conventional regulating unit  35  and outlet piping  36 . Of course, high pressure gas piping system  30  is provided with other piping and components which will not be discussed or illustrated in detail herein. For example, high pressure gas piping system  30  can include various gas bypass piping, pressure and temperature sensors, and other components that are well known in the natural gas industry. 
     The metering unit  32  is shown with an 8″ Equimeter Auto-Adjust turbine meter. Of course, other types of metering units can be used. The metering unit  32  has a maximum rating of approximately 3,345 Mcfh at the inlet pressure of approximately 800 psig and a minimum rating of approximately 27.3 Mcfh at an inlet pressure of approximately 1200 psig. Dual outputs from main and correcting impellers of metering unit  32  are split and isolated with a Pepperl-Fuchs barrier. Standard electronic readouts will be provided to perform the adjustment calculations. Preferably, a flow control valve  33  is installed on the high pressure gas piping system  30 . The flow control valve  33  can be, for example, an 8″ Grove B-ball valve with a Becker actuator. 
     The high pressure gas metering and regulating room  11  is also preferably equipped with a forced ventilation system, which will be designed to provide fresh air to the high pressure gas metering and regulating room  11  several in an hour when activated. An explosion proof electric heater can also be installed to keep the high pressure gas metering and regulating room  11  above a predetermined temperature such as 50° F. Explosion proof incandescent lighting  29  can also be installed to provide an appropriate illumination level for the high pressure gas metering and regulating room  11 , for example an illumination level of approximately 50 footcandles. Referring now to FIGS. 1,  2  and  4 , odorant room  12  is designed to add odor to the natural gas exiting the gas delivery station  10 . Specifically, natural gas in its pure form is an odorless gas. Accordingly, odor is often added to natural gas so that the end user or consumer can smell the gas in the event of a gas leak. Accordingly, odorant room  12  can be added to the gas delivery station  10  when it is necessary to add an odor to the natural gas exiting the gas delivery station  10 . Odorant room  12  basically includes a flat base  40 , a pair of flat end walls  41 , a pair of flat side walls  42  and an angled roof  43 , which together form a three-dimensional, rectangular building module. 
     As shown in FIG. 1 and 2, end walls  41  are designed to mate with two of the other rooms or modules. For example, end walls  41  can be mated with one of the end walls  21  of high pressure gas metering and regulating room  11  and one of the end walls boiler room  13  to form a continuous integrated building. When high pressure gas metering and regulating room  11  and odorant room  12  are fixedly coupled together, side walls  42  of odorant room  12  form a continuous wall with side wall  22  of high pressure gas metering delivery room  11 . Likewise, base  40  of odorant room  12  forms a continuous base with base  20  of high pressure gas metering and regulating room  11 , and roof  43  of odorant room  12  forms a continuous roof with roof  23  of high pressure gas metering and regulating room  11 . Odorant room  12  is preferably fabricated of concrete that is designed to be fire-rated and gas impermeable in accordance with the safety regulatory requirements for the industry. One of the side walls  42  is preferably provided with a pair of doors  44 , which can be equipped with panic hardware. Also, one or more access openings are provided in one or both of the side walls  42  such that piping and/or wiring can be easily brought into or out of odorant room  12 . 
     Odorant room  12  is preferably provided with an odorant tank  46  and an odor injection system  48 . Odor injection system  48  is a conventional odor injection system that controls and regulates the odor being added to the natural gas. Since such odorant tanks and odor injection systems are well known within the art, odorant tank  46  and odor injection system  48  will not be discussed or illustrated in detail herein except for as it relates to the uniqueness of the present invention. Of course, it will be apparent to those skilled in the art from this disclosure that odorant room  12  can be provided with other piping and components which will not be discussed or illustrated herein. 
     Odor injection system  48  is fluidly coupled between odorant tank  46  and outlet piping  36  via piping  49 . Piping  49  extends from odor injection system  46  out of odorant room  12  via an access opening and then runs along the exterior of high pressure gas metering and regulating room  11 . Piping  49  is then coupled to outlet piping  36 . Accordingly, no openings are formed in the end walls of either of high pressure gas metering and regulating room  11  or odorant room  12 . 
     Odorant tank  46  and odor injection system  48  are fixedly secured to base  40  and/or end walls  41  and/or side walls  42  of odorant room  12  in a conventional manner. Likewise, the various electrical components and/or lighting fixtures  45  of odorant room  12  are mounted on the concrete end walls  41  and/or side walls  42  of odorant room  12  in a conventional manner as needed and/or desired. 
     Referring now to FIGS. 1,  2  and  5 , boiler room  13  preferably includes a flat base  50 , a pair of flat end walls  51 , a pair of flat side walls  52  and an angled roof  53 , which together form a three-dimensional, rectangular building module that can be fixedly coupled to other modules. Accordingly, boiler room  13  is a three-dimensional module having substantially the same cross-sectional configuration as the other rooms or modules such that it can be mated with the other rooms or modules. In other words, end walls  51  of boiler room  13  are sized and shaped to be mated with the end walls of one or more of the other rooms or modules  11 ,  12 ,  14  and  15 . When boiler room  13  is fixedly coupled to the end walls of the other rooms or modules  11 ,  12 ,  14  and  15 , a continuous integrated building is formed. The boiler room  13  is preferably fabricated of concrete that is designed to be fire-rated and gas impermeable in accordance with the safety regulations for the industry. 
     Boiler room  13  preferably includes a pair of heaters  54  and a pair of circulating pumps  55  coupled via piping to heat exchanger  34 . Of course, it will be apparent to those skilled in the art from this disclosure that boiler room  13  can be provided with other standard or customized components which will not be discussed or illustrated herein. Heaters  54  are designed to transfer heat to the natural gas flowing through piping system  30  in a non-hazardous manner. Preferably, heaters  54  are propylene glycol/water heaters that are arranged in series with circulating pump  55 . 
     By placing heaters  54  within a separate boiler room  13 , noise to the surrounding environment can be minimized. In particular, the concrete walls  51  and  52  will reduce the amount of noise, which can be heard from gas delivery station  10 . Moreover, noise attenuation devices and/or acoustical panels can be installed to walls  51  and  52  as needed and/or desired. 
     The propylene glycol/water heaters  54  preferably utilize natural gas at a pressure of 7-9″ water column, with each having the maximum input of approximately 3,050,000 Btu/h for a total maximum usage of approximately 6.1 MMBtu/h. More specifically, heaters  54  and pump  55  are fluidly coupled to heat exchanger  34 . The heat exchanger  34  is preferably a shell and tube heat exchanger with a three-way valve connected to the supply line and return line for heaters  54  and pump  55 . 
     In the heat exchanger  34 , natural gas enters one side of the inner tube of heat exchanger  34  at pipeline pressure, and glycol/water enters the shell of the heat exchanger  34  from the opposite side via the supply line. As the gas flows through the tube of the heat exchanger  34 , the gas is heated by the glycol/water surrounding the outside of the inner tube and is preheated to a desired temperature. In other words, the glycol/water fluid is pumped through the heaters  54  to the heat exchanger  34  via pump  55  thereby warming the natural gas in the tubes. The glycol/water fluid is then returned to the heaters  54  via one or more pumps  55 . A temperature controller mounted in the gas metering and regulating room  11  senses the downstream temperature. The temperature controller is preferably set to maintain a predetermined set point temperature of downstream gas such as 40° F. The temperature controller sends a signal to the three-way valve that controls the amount of fluid entering the heat exchanger  34  based on the downstream gas temperature. While heat exchanger  34  is located downstream of the metering unit  32  in FIGS. 2,  3  and  8 , heat exchanger  34  can be located upstream of the metering unit  32  as seen in FIG.  9 . 
     The benefit of placing the heat exchanger  34  upstream of the metering unit is that a more accurate measurement of the gas being withdrawn from the pipeline can be obtained. More specifically, sometimes the gas from the pipeline separates into two phases, i.e., a liquid phase and a vapor phase. This may result in an erroneous reading by the metering unit  32 . By preheating the gas prior to entering metering unit  32 , the system ensures that the gas is in its proper phase and at the proper temperature for accurately determining the amount of gas being withdrawn from the pipeline. In other words, this arrangement gives better control of all the conditions of the gas to be metered. 
     Heaters  54  preferably have aquastats and operate on water bath control. A backup aquastat can be provided to shut the unit off with a manual reset to reactivate heaters  54 . Standard IRI burner controls provide high and low fuel pressure protection as well as double lock and lead protection. A low water cut off with manual reset is also preferably provided. A flow switch is preferably mounted on the inlet of each heater  54 . A common trouble contact closure indicates problems on the unit that can activate a 24 volt DC signal as a digital input to the remote terminal unit located in electrical room  15 . A 24 volt DC signal is then sent as a digital output from the remote terminal unit to shut the unit down. A combustible vapor detector and heat detector can also be installed in the boiler room  13 . 
     Boiler room  13  is preferably provided with vents  56  to provide adequate combustion air without using power venting. The lighting level for this room is approximately 50 footcandles. The electrical control room  15  will also have an HVAC unit installed to maintain environment as needed for the equipment installed in the room. The lighting level for this room is approximately 50 footcandles. The doors  57  can be optionally equipped with panic hardware if needed and/or desired. 
     Referring now to FIGS. 1,  2  and  6 , energy generation room  14  basically includes a flat base  60 , a pair of flat end walls  61 , a pair of flat side walls  62  and an angled roof  63 , which together form a three dimensional, rectangular building module. Accordingly, energy generation room  14  is a three-dimensional module having substantially the same cross-sectional configuration as the other rooms or modules such that it can be mated with the other rooms or modules. In other words, end walls  61  of energy generation room  14  are sized and shaped to be mated with the end walls of the other rooms or modules  11 ,  12 ,  13  and  15 . When energy generation room  14  is fixedly coupled to the end walls of one or more of the other rooms or modules  11 ,  12 ,  13  and  15 , a continuous integrated building is formed. The energy generation room  14  is preferably fabricated of concrete that is designed to be fire-rated and gas impermeable in accordance with the natural gas industries&#39; safety regulatory requirements. 
     Each of the side walls  62  are preferably provided with a door  64  that can be equipped with panic hardware if needed and/or desired. Energy generation room  14  preferably includes a natural gas generator  65  which is fluidly coupled to high pressure gas piping system  30  such that natural gas generator  65  can operate on the natural gas which is being metered. Preferably, a natural gas supply line  66  runs from generator  65  to the downstream end of gas piping system  30  for supplying natural gas to generator  65 . Supply line  66  preferably exits room  14  via the rear side wall  62  and then runs along the exterior of station  10 . The supply line  66  then enters room  11  via access opening  28  for connection with gas piping system  30 . Accordingly, gas metering station  10  is completely self-sufficient in that it can provide its own source of electrical power via generator  65 . 
     Preferably, generator  65  is a 560 kW natural gas generator with a storage battery and charger unit  67  coupled thereto for storing and utilizing electrical energy generated from generator  65 . Also, a generator control panel  68  and a utility interface panel  69  are also preferably mounted within energy generation room  14  and electrically coupled to gas generator  65  for controlling the electrical energy being supplied to gas metering station  10  via gas generator  65 . Generator control panel  68  and utility interface panel  69  act together as a dual power control unit which allows the gas metering station to be operated either off of electrical energy provided from an electrical utility line or from generator  65 . Of course, it will be apparent to those skilled in the art from this disclosure that energy generation room  14  can be provided with other components and/or lighting fixtures which will not be discussed or illustrated herein. For example, generator  65  can be provided with heat exchangers and pipings that are connected to the piping of the boiler room  13  to utilize heat produced by generator  65 . 
     Referring now to FIGS. 1,  2  and  7 , electrical control room  15  is provided with conventional supervisory control and data acquisition (SCADA) equipment having communications equipment. The flow computer and SCADA interface for the supply pipeline and the end user reside in this room. The electrical control room  15  basically includes a base  70 , a pair of end walls  71 , a pair of side walls  72  and a roof  73 , which together form a three dimensional, rectangular building module. Accordingly, electrical control room  15  is a three-dimensional module having substantially the same cross-sectional configuration as the other rooms or modules such that it can be mated with the other rooms or modules. In other words, end walls  71  of being sized and shaped to be mated with the end walls of the other rooms or modules  11 ,  12 ,  13  and  14 . When electrical control room  15  is fixedly coupled to the end walls of the other rooms or modules  11 ,  12 ,  13  and  14 , a continuous integrated building is formed. The electrical control room  15  is preferably fabricated of concrete that is designed to be fire-proof and gas impermeable in accordance with the natural gas industries&#39; safety regulatory requirements. 
     Each of the side walls  72  preferably has a door  74  for accessing electrical control room  15 . Electrical control room  15  is preferably provided with standard electrical equipment, including an electrical service unit  75  which is designed to be a 277/480 volt, three phase, 200 amp service. The electrical service unit  75  can be provided with a transfer switch to allow for addition of on-site electrical generation either permanent or temporary. An uninterrupted power source (UPS)  76  is also preferably provided to supply standby power to the emergency instruments and control devices for eight hours, and emergency lighting for a minimum of fifteen minutes. The non-hazardous electrical control room  15  contains the electrical service termination at the breaker panel, an electric meter, and voice and data telephone for the pre-manufactured gas delivery station  10 . Of course, it will be apparent to those skilled in the art from this disclosure that electrical control room  15  can be provided with other electrical components such as a remote terminal unit. 
     The electrical design for the pre-manufactured gas delivery station  10  is based on a hazardous designation for the high pressure gas metering and regulating room  11  and a non-hazardous destination for the remaining rooms, i.e., the odorant room  12 , the boiler room  13 , the energy generation room  14  and the electrical control room  15 . The flow controllers as well as the explosion-proof transmitters are installed in the hazardous area to control the valves and to send back the pre-requisite, temperature and flow information to the remote terminal unit which is connected to electrical control room  15 . Explosion-proof and incandescent lighting and outlets are installed in the hazardous areas. The power and controllers for all of the rooms or modules  11 - 15  are provided by the electrical control room  15 . The glycol/water pump  55  and the glycol/water heaters  54  are also located in a non-hazardous room and are wired with standard non-hazardous fittings and controls. The pump  55  operates on  208 , three-phase for power, while the heaters  54  requires 120 volt AC for power. The electrical control room  15  also contains non-hazardous incandescent lighting fixtures  79  and outlets in addition to a combustible gas detector. 
     As previously mentioned, a basic concept of the present invention is to create a pre-manufactured gas delivery station at relatively low costs and more quickly than if built at the installation site. This method of the present invention requires a predetermined set of modular buildings  11 - 15  to be prefabricated at a factory site for constructing the building that either forms a pre-manufactured gas delivery station  10  or forms part of an existing gas delivery station. As mentioned above, these modular buildings  11 - 15  are configured to be coupled together to form a single integrated unit. In the preferred embodiment, the predetermined set of modular buildings  11 - 15  includes at least a high pressure gas metering and regulating room  11 , an odorant room  12 , a boiler room  13 , an energy generation room  14 , and an electrical control room  15 . These modular rooms  11 - 15  are combined at the factory site such that at least one of the predetermined set of modular rooms  11 - 15  is combined with at least one other of the predetermined set of modular rooms  11 - 15  at the factory site to form a customer selected building. Once the rooms are assembled, the building is shipped from the factory site to the installation site, which is remote from the factory site. 
     In accordance with this method of the present invention, the customer can select predetermined set of modular rooms which preferably includes a high pressure gas regulating and metering room, an odorant room, a boiler room, an energy generation room and an electrical control room. Of course, other modules or rooms can be included in the predetermined set of modular buildings  11 - 15  from which the customer can create the pre-manufactured gas delivery station  10 . Moreover, it is possible that a module can be constructed which is not one of the prefabricated modules. In other words, the customer can have a pre-manufactured gas delivery station  10  that includes both the prefabricated modules and completely customized modules. The prefabricated rooms or modules are typically outfitted such that certain basic equipment is built into all similar prefabricated rooms or modules. Of course, additional custom features can be added to the basic prefabricated rooms or modules at the factory site as needed and/or desired by the customer. 
     The building modules are loaded with control system equipment and thoroughly tested at the factory site to ensure that all systems are operational. Thereafter, the fully pre-fabricated gas delivery station  10  is transported to the industrial or commercial installation site and installed at such installation site utilizing conventional techniques. Gas delivery stations  10  constructed in accordance with the present invention can be used in a wide variety of applications, which require the use of relatively complex electrical and electronic equipment. As indicated above, the present invention can be used to erect a fully equipped ready-to-operate gas metering station with minimal time and labor at the installation site. The present invention affords substantial advantages and savings in that a very large portion of the equipment installation work, equipment adjustment work and testing is efficiently and economically performed at the factory or manufacturing site which is better equipped and better staffed to manufacture the gas metering station. 
     At the factory site, the equipment, the electrical wiring and the piping are all installed into each of the building modules  11 - 15 . All of the equipment is preferably bolted down or otherwise secured within its particular building module or room so that it will remain at a fixed location therein during transportation. The various pieces of equipment that are installed in each of the building units are interwired and/or piped with one another at the factory site to form the gas delivery station  10 . All of the equipment installed in the building modules  11 - 15  are thoroughly tested at the factory site. This testing includes combined testing of the equipment interconnected so as to operate as a single unit. All major and, if necessary, minor control equipment adjustments are preferably made at the factory so that minimal amount of adjustments will be needed at the installation site. 
     While only one embodiment has been chosen to illustrate the present invention, it will be apparent to those skilled in the art from this disclosure that various changes and modifications can be made herein without departing from the scope of the invention as defined in the appended claims. Furthermore, the foregoing description of the embodiments according to the present invention are provided for illustration only, and not for the purpose of limiting the invention as defined by the appended claims and their equivalents.