Abstract:
A lift station containing a tube, an access box connected to the tube, and an inner pipe that is removable, positioned in the tube that can be used to contain and discharge process water. The design aids in construction and maintenance and can detect leaks that can reduce process water contamination of surrounding soil.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    Not applicable. 
       FIELD 
       [0002]    The embodiments of the present invention relate to lift stations for the collecting and disposing of process water. 
       BACKGROUND 
       [0003]    Industrial processes typically involve the use of hydrocarbons, such as oil, and other compositions that require specialized disposal. During the course of operations of industrial processes, the oil and other compositions requiring specialized disposal can be mixed with water from various sources, such as for example pressure washing. The mixture of water with oil and/or other contaminants is typically referred to as process water. Process water cannot be directly disposed of due to the oil and/or other contaminants in the process water. 
         [0004]    Process water typically passes from work areas through an ordinary underground oil-water separator and then into a cleaning system. The pumps and switches which move the water from the separator to the cleaning system are not typically placed inside the separator itself in order to allow for maintenance access. Instead, the pumps and switches are placed in a lift station, which is essentially a tub positioned in a convenient location and supplied with water from the separator via gravity. Pumps and float switches in the lift station are designed to move the water into the cleaning system. 
         [0005]    Current lift stations are generally constructed by placing a length of cement culvert vertically in the ground and pouring additional concrete therein to form a bottom. However, the wet concrete poured into the ground may not seal with the culvert, which can result in underground leakage of process water. Lift stations can also be constructed from pre-formed fiberglass or plastic. However, these pre-formed lift stations can crack underground, which can cause process water to unknowingly leak into the soil. Additionally, pre-formed lift stations may not have the desired shape, size, or aspect ratio for each specific project. 
         [0006]    Since lift stations are normally buried at the same depth as the separator, cleaning soil contaminated by leaking process water can be extremely expensive and disruptive. Cleaning the surrounding soil typically requires the destruction of concrete, the removal of large amounts of dirt, and the replacement of piping. 
         [0007]    In view of the above, it would be desirable to have a lift station that can be customized to any construction project or installation area. It would also be desirable to detect an underground leak before process water has entered the soil. Furthermore, it would be desirable to have a lift station that allows for the easy removal and replacement of leaking parts. 
       SUMMARY 
       [0008]    An embodiment of the present invention is a lift station that includes a tube, an access box connected to the tube, and an inner pipe positioned in the tube. The inner pipe can be removable from the tube and the space between the tube and the inner pipe can form an inspection window where water can be observed if the inner pipe were to leak. There can be at least one centralizer positioned between the tube and the inner pipe, which can be made of rods, plates, or pad eyes. The inspection window can be a space of at least 0.5 inch (1.27 centimeters) between the tube and the inner pipe. 
         [0009]    A pump can be located at the bottom end of the inner pipe that can be activated by a float switch located inside the inner pipe. The pump can remove process water from the lift station. 
         [0010]    The inner pipe can have an inlet pipe attached to a side wall of the inner pipe that enables process water to enter the inner pipe. The tube can have a groove in its side wall that allows for the removal and/or placement of the inner pipe with the inlet pipe, where the inlet pipe is located within the groove. 
         [0011]    The tube and the inner pipe can be made of materials such as carbon steel, stainless steel, iron, aluminum, fiberglass, plastic, and any other polymeric material and any combinations thereof. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0012]      FIG. 1  is a side view of a lift station of an embodiment of the present invention. 
           [0013]      FIG. 2  is a bottom view of a lift station of an embodiment of the present invention. 
           [0014]      FIG. 3  is a top view of a lift station of an embodiment of the present invention. 
           [0015]      FIG. 4A  is an exploded view of a lift station of an embodiment of the present invention. 
           [0016]      FIG. 4B  is an exploded view of an inner pipe portion of an embodiment of the present invention. 
           [0017]      FIG. 4C  is an exploded view of a tube portion of an embodiment of the present invention. 
           [0018]      FIG. 4D  is a perspective cross-sectional view of an access box portion of an embodiment of the present invention. 
           [0019]      FIG. 5  is a perspective cross-sectional view showing component parts of a lift station of an embodiment of the present invention. 
           [0020]      FIG. 6  illustrates the function of a lift station of an embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0021]    The present invention provides for a lift station that allows for the early detection of leaks. In the case of leaks, the present invention also provides for easy removal and replacement or repair of the leaking components. 
         [0022]    Referring to  FIGS. 1 and 2  of the drawings, there is shown an embodiment of a lift station of the present invention.  FIG. 1  depicts a side view of the lift station  2  having a tube  4  that is connected to an access box  6 .  FIG. 2  depicts a bottom view of the lift station  2  having a tube  4  that is connected to an access box  6 . 
         [0023]      FIG. 3  depicts a top view of the lift station  2  containing a tube  4  connected to an access box  6  having a ladder  16 . The access box also contains an outer lip  20  that surrounds at least a portion of the top edge of the access box  6 . The outer lip  20  can be used to secure the lift station  2  to a foundation or other means of support. An inner pipe  8  is positioned within the tube  4  and held in place by centralizers  12 ( a - e ) such that a space, also referred to as an inspection window  10 , is created between the tube  4  and the inner pipe  8 . In an embodiment, the inspection window is a space of at least 0.5 inch (1.27 centimeters) between the tube  4  and the inner pipe  8 . In another embodiment, the inspection window is a space ranging from 1 to 5 inches (2.54 to 12.7 centimeters) between the tube  4  and the inner pipe  8 . A probe, float device or other means to detect water can be placed within the inspection window  10  to detect any water that may leak from the inner pipe  8 .  FIG. 3  also depicts where the inner pipe  8  is connected to an inlet pipe  14 , which is situated within a groove  18  in the tube  4 . The groove  18  enables the removal of the inner pipe  8  from the tube  4  with minimal disassembly of the lift station  2  components. 
         [0024]    In an embodiment, the lift station  2  can be constructed of any desired material. In an embodiment, the lift station  2  is constructed of materials selected from the group of carbon steel, stainless steel, iron, aluminum, fiberglass, plastic, and any other polymeric material and any combinations thereof. In an embodiment, the tube  4  is constructed of materials selected from the group of carbon steel, stainless steel, iron, aluminum, fiberglass, plastic, and any other polymeric material and any combinations thereof. In an embodiment, the inner pipe  8  is constructed of materials selected from the group of carbon steel, stainless steel, iron, aluminum, fiberglass, plastic, and any other polymeric material and any combinations thereof. 
         [0025]    Referring now to  FIG. 4A , a lift station  40  is depicted in an exploded view showing the component parts of the lift station  40 .  FIG. 4A  shows the lift station  40  as being composed of essentially three main parts, which include the access box  42 , the tube  44  and the inner pipe  46 . 
         [0026]      FIG. 4B  illustrates in detail the inner pipe  46 . This inner pipe  46  is capable of being lowered into and removed from the tube  44  (depicted in  FIG. 4A ), thus limiting the amount of work needed to replace a leaking inner pipe. In an embodiment, the inner pipe  46  has an inner diameter ranging from 1 inch to 100 inches (2.54 centimeters to 254 centimeters). In another embodiment, the inner pipe  46  has an inner diameter ranging from 10 to 50 inches (25.4 to 127 centimeters). In a further embodiment, the inner pipe  46  has an inner diameter ranging from 20 to 40 inches (50.8 to 101.6 centimeters). In an embodiment, the inner pipe  46  has a length ranging from 3 feet to 30 feet (91 meter to 9.14 meters). In another embodiment, the inner pipe has a length ranging from 5 feet to 20 feet (1.52 meters-to 6.1 meters). In an aspect, the inner pipe  46  is shorter than the tube  44 . In another aspect, the inner pipe  46  is at least 1% shorter than the tube  44 . In a further aspect, the inner pipe  46  is at least 10% shorter than the tube  44 . In the embodiment illustrated, the inner pipe is the same length as the outer pipe. However, it is only necessary that the inner pipe be of a length equal to the distance from the floor plate of the outer pipe to the top of the inflow pipe. 
         [0027]    An inner pipe floor plate  50  is connected to the bottom end  52  of the inner pipe  46 . In an embodiment, the inner pipe floor plate  50  is connected to the bottom end  52  of the inner pipe  46  creating a leak-free seal between the inner pipe  46  and the inner pipe floor plate  50 . In another embodiment, the inner pipe floor plate  50  is welded to the bottom end  52  of the inner pipe  46 . In a further embodiment, the inner pipe  46  is constructed, or molded, to create a one-piece construction such that the inner pipe floor plate  50  is integrated with the bottom end  52  of the inner pipe  46 . 
         [0028]    An inlet hole  54  is present on the side wall of the inner pipe  46  through which an inlet pipe  56  is positioned. The inlet hole  54  may be positioned at a point along the side wall of the inner pipe  46 . In an embodiment, the inlet hole  54  and inlet pipe  56  are positioned in the side wall of the inner pipe  46  such that the inlet pipe  56  faces the access box  42 . 
         [0029]    The inner pipe  46  contains an upper end  58 . Lifting hole(s)  60  can be located at the upper end  58  of the inner pipe  46  in order to aid in the installation and removal of the inner pipe  46  into and out of the tube  44  of the lift station  40 . The lifting hole(s)  60  can include holes, grooves, handles, gaps, or any other feature that can aid in the lifting of the inner pipe  46 . Centralizers  62 ( a - e ) may also be located at the upper end  58  of the inner pipe  46  in order to position the inner pipe  46  in the center of tube  44 . In an embodiment, the centralizers  62 ( a - e ) includes at least one centralizer. In another embodiment, the centralizers  62 ( a - e ) include 2 to 8 centralizers. The centralizers  62 ( a - e ) can include rods, plates, pad eyes, or any other projection. The centralizers  62 ( a - e ) can be welded to, integral with, fastened to, or otherwise attached to the exterior of the inner pipe  46 . In another embodiment, one or more of the centralizers  62 ( a - e ) serve as lifting lugs in addition to the centralizing the inner pipe  46  in the tube  44 . Additional centralizers can be located along the length of the inner pipe  46 , such as in the middle and/or bottom of the inner pipe  46 . 
         [0030]      FIG. 4C  illustrates in detail the tube  44 . In this illustration the tube  44  contains an outer hull  66  that is capable of receiving the inner pipe  46  (depicted in  FIGS. 4A and 4B ) and of restraining any leaks that may arise from the inner pipe  46 . In an embodiment, the tube  44  has an inner diameter ranging from 2 to 120 inches (5.08 to 304.8 centimeters). In another embodiment, the tube  44  has an inner diameter ranging from 15 to 75 inches (38.1 to 190.5 centimeters). In a further embodiment, the tube  44  has an inner diameter ranging from 25 to 50 inches (63.5 to 127 centimeters). In an embodiment, the tube  44  has a length ranging from 5 feet to 40 feet (1.52 meters to 12.19 meters). In another embodiment, the tube  44  has a length ranging from 7 feet to 30 feet (2.13 meters to 9.14 meters). In an aspect, the inner pipe  46  is shorter than the tube  44 . In another aspect, the inner pipe  46  is at least 1% shorter than the tube  44 . In a further aspect, the inner pipe  46  is at least 10% shorter than the tube  44 . The tube  44  also contains a groove  68 . Groove  68  is designed to allow for the passage of the inlet pipe  56  (depicted in  FIG. 4B ) attached to the inner pipe  46 , when the inner pipe  46  is lowered into the tube  44 . The groove  68  facilitates the removal of the inner pipe  46  for maintenance or repairs. The tube  44  may also contain a sump (not shown) for collecting water, sand, etc. In an embodiment, rods, plates, pad eyes, or any other projection may be welded to, integral with, fastened to, or otherwise attached to the inner surface of the tube  44  to space the inner pipe  46  within the tube  44 . In an embodiment, rods, plates, pad eyes, or any other projection may be welded to, integral with, fastened to, or otherwise attached to the outer surface of the tube  44  to space the tube  44  within the access box  42 . 
         [0031]    A tube floor plate  70  is connected to the bottom end  72  of the tube  44 . In an embodiment, the tube floor plate  70  is connected to the bottom end  72  of the tube  44  creating a leak-free seal between the tube  44  and the tube floor plate  70 . In another embodiment, the tube floor plate  70  is welded to the bottom end  72  of the tube  44 . In a further embodiment, the tube  44  is constructed, or molded, to create a one-piece construction such that the tube floor plate  70  is integrated with the bottom end  72  of the tube  44 . In an aspect, the tube floor plate  70  has an outer diameter greater than the outer diameter of the tube  44 . In another aspect, the tube floor plate  70  has an outer diameter ranging from 1 to 10 inches (2.54 to 25.4 centimeters) larger than the outer diameter of tube  44 . The larger tube floor plate  70  can be used to create an anti-flotation flange that could anchor the assembly and prevent the floatation of the tube  44  in case of high or rising ground water that could act to raise the lift station from its desired location. 
         [0032]      FIG. 4D  illustrates in detail an embodiment of the access box  42 . In this illustration, access box  42  contains a ladder  80  and a standing area  82 . The access box  42  contains a lip  84  that is designed to wrap around the top of the lift station  2  allowing the lift station  2  to rest on concrete or any other type foundation or support. The access box  42  also contains a hole  86  for bringing water into the lift station  2 . The access box  42  may also contain studs  88  on the outer surface of the access box wherein the studs  88  are designed to project into concrete or other type foundation in order to anchor the lift station  2 . In an embodiment the lift station  2  includes a lid for covering the top of the lift station to restrict rain water or surface water from entering the lift station. 
         [0033]      FIG. 5  depicts a perspective cross-sectional view of a lift station of the present invention. The lift station  100  contains an inner pipe  102  having a pump  104  located at the bottom of the inner pipe  102 . The pump  104  can be activated by a float switch  106  wherein the float switch is located in the inner pipe  102 . The pump  104  and/or float switch  106  can be located within or adjacent to the lift station  100 , such as in the access box. The access box can include areas for controls, switches, wires, pipes, etc. 
         [0034]    An oil-water separator  108  can be used to supply water to the inner pipe  102  via a first pipe  110  connected to the oil-water separator  108  on one end and to the inlet pipe  112  on the other end. The inlet pipe  112  may optionally contain a rubber boot and hose clamps  114  to aid in connecting the inlet pipe  112  with the first pipe  110 . Water may be removed from the inner pipe  102  via a second pipe  116  that is connected to the pump  104 . The first pipe  110  can be sealed within the hole in the access box for bringing water into the lift station. 
         [0035]    The first pipe  110 , inlet pipe  112  and inner pipe  102  can form a closed system that keeps the water from entering the access box. If a leak is present in any of these components the leaking water will enter the access box or the space between the inner pipe and the tube, which can be referred to herein as an inspection window. Water leaking into the inspection window and can rise to a height where it can pass through the groove/slot in the tube and enter the access box where it can be contained and detected. Water detectors can be included in the inspection window and/or in the access box which can detect and signal whether water has entered these areas. A tightly-fitting cap can be emplaced covering the top of the entire assembly (access box and outer tube) in order to prevent rain or other water from entering the access box and inspection window. 
         [0036]      FIG. 6  depicts a flow scheme of a lift station  200 . Arrow  210  shows water gravity feeding in from a separator (not shown). Arrows  220  show water gravity feeding through a rubber boot (not shown) connecting the separator outflow with the inner pipe  230 . Arrow  240  shows water being pumped out of the lift station, such as to water reclamation equipment. 
         [0037]    Various terms are used herein, to the extent a term used in not defined herein, it should be given the broadest definition persons in the pertinent art have given that term as reflected in printed publications and issued patents. 
         [0038]    Depending on the context, all references herein to the “invention” may in some cases refer to certain specific embodiments only. In other cases it may refer to subject matter recited in one or more, but not necessarily all, of the claims. While the foregoing is directed to embodiments, versions and examples of the present invention, which are included to enable a person of ordinary skill in the art to make and use the inventions when the information in this patent is combined with available information and technology, the inventions are not limited to only these particular embodiments, versions and examples. Other and further embodiments, versions and examples of the invention may be devised without departing from the basic scope thereof.