WASTEWATER TREATMENT APPARATUS AND SYSTEM FOR OIL AND GAS PRODUCTION WELLS

Abstract

The present invention comprises a closed loop system for the removal of contaminants from wastewater while evaporating the water by utilizing a continuously running evaporator in communication with a separation tank wherein water is returned to the evaporator and solids are left in the separation tank for disposal.

Claims

1. A wastewater treatment system comprising: a holding tank for wastewater wherein said wastewater includes solids therein and wherein said holding tank has an inlet for receiving and an outlet for passing said wastewater; an evaporator for evaporating said wastewater, having an inlet for receiving said wastewater from said holding tank outlet, an outlet for passing said wastewater that is unevaporated and said solids from said wastewater; and a separator for separating and collecting said solids from said wastewater, having an inlet for receiving from said evaporator said wastewater that is unevaporated and said solids from said wastewater and an outlet for passing said wastewater to said holding tank inlet.

2. The wastewater treatment system of claim 1 wherein said evaporator is a submerged combustion evaporator.

3. The wastewater treatment system of claim 2 wherein said wastewater is from a producing oil and gas well.

4. The wastewater treatment system of claim 3 wherein said evaporator outlet is in communication with a pump for passing said wastewater and said solids to said separator inlet.

5. The wastewater treatment system of claim 4 wherein said pump is a diaphragm pump.

6. The wastewater treatment system of claim 5 wherein said separator outlet further includes a filter for filtering said wastewater before passing said wastewater to said holding tank inlet.

6. The wastewater treatment system of claim 6 wherein said filter is made from fabric.

8. The wastewater treatment system of claim 7 further including a skid adapted to support said separator at a slope with said separator outlet at the bottom of said slope.

9. The wastewater treatment system of claim 8 wherein said separator is adapted to be utilized as a roll-off for transportation.

10. The wastewater treatment system of claim 9 wherein said skid further includes a drip pan.

Description

BRIEF DESCRIPTION OF THE PICTORIAL ILLUSTRATIONS, GRAPHS, DRAWINGS AND APPENDICES

[0031] The invention will be better understood and objects other than those set forth above will become apparent when consideration is given to the following detailed description thereof. Such description makes reference to the annexed pictorial illustrations, graphs, drawings and appendices wherein:

[0032] FIG. 1 is a general illustration of a preferred embodiment of the invention.

[0033] FIG. 2 is general illustration of a preferred embodiment of the invention but not depicting an evaporator.

[0034] FIG. 3 is a general perspective view illustration of a preferred embodiment of the invention but not depicting an evaporator.

[0035] FIG. 4 is general side view illustration of a preferred embodiment of the invention but not depicting an evaporator.

[0036] FIG. 5 is a general perspective view illustration with a partial cut away of a preferred embodiment of the invention but not depicting an evaporator.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0037] Referring to the illustrations, drawings, and pictures and to FIG. 1 in particular, reference character 10 generally designates a new and improved apparatus, system and method of using same constructed in accordance with the present invention. Invention 10 is generally used with a well utilized for the retrieval of hydrocarbons below the surface. It is understood that invention 10 may be utilized in numerous other applications where it is desirable to treat wastewater and the current invention should not be considered limited to just oil and gas applications. Furthermore, it is also to be understood that the current invention is not limited to flow back water operations, well production, drilling operations, permanent placement and so forth. It is understood that numerous other applications in the oil and gas supply chain are contemplated where it is desirable to treat wastewater by concentrating and or separating solids from liquids. It is therefore understood that the current invention may be utilized with multiple applications.

[0038] Invention 10 contemplates providing solids management for a submerged combustion process through solids removal, solids storage, solids dewatering and generally forming a dewater cake to meet landfill requirements and or will pass a paint filter test. Invention 10 contemplates a process that allows continuous or intermittent operation to manage solids such as but not limited to transfer via pressure pumping, separation via gravity, separation via retention, separation via filter media, separation via crystallization caused by temperature change and or transfer via gravity.

[0039] Therefore, invention 10 may generally comprise a wastewater source 20 such as but not limited to a holding tank, staging tank, inlet pipe and so forth, an evaporator and or treating tank system 30 for treating influent water and or wastewater 40, a separation tank 50 in communication with evaporator 30. It is contemplated that evaporator 30 may utilize submerged combustion heating for evaporation although it is understood that the current invention is not limited to such. Other forms of wastewater treatment systems known in the art are contemplated to be used in association with the current invention as well as other types of evaporators. Treating tank 30 may be referred to in the specification as evaporator, evaporator tank, evaporation tank, evaporator system and so forth. Separation tank 50 may be referred to in the specification as separator, separator tank, resting tank, separation tank system and so forth. Wastewater source 20 may also be referred to as holding tank, stock tank, staging tank and so forth.

[0040] As known in the prior art, submerged combustion heating is generally a method whereby hot products of combustion are forced through a liquid or liquid-solid mixture to heat the liquid or liquid-solid mixture. An advantage of this heating system is that the heat exchange occurs directly between the hot gaseous products of combustion and the liquid. In a submerged combustion system and or evaporator, the hot combustion is typically fuelled by a combination of air and natural gas. Another benefit of such application is the natural gas needed to fuel the evaporation may come from the well operation thereby eliminating the need for transporting a fuel.

[0041] In a desalination process, solids 35 such as but not limited to salts, minerals and other various matter are generally dissolved, broken down, burned and or suspended for separating from the wastewater 40. Solids 35 are further discussed below regarding compositions types and the term “solids 35” should not be considered to limit the invention as such and is to be considered to generally refer to solid matter in the wastewater 40.

[0042] In a thermal process, as the influent water and or wastewater 40 is heated, the dissolved solids 35 become concentrated and turn into suspended solids 35. After the dissolved solids 35 become suspended, the concentrated solids 35 fall to the bottom of treating tank 30 in which the heat treating occurs, while the free wastewater moves towards the top of treating tank 30 in the form of a vapor 60. The vapor 60 then exits the treating tank 30 through an opening and or aperture 70, most commonly referred to as a stack or an exhaust. To continue the desalination process, the solids 35 eventually must be removed from the treating tank 30.

[0043] The output 80 from evaporator 30 that is not in the form of vapor 60 generally comprises heavy hydrocarbons 90, precipitated solids 100 once dissolved, small solids 110, formation solids 120 and high total dissolved solid in water and or liquids 130 also referred to as TDS water. Formation solids 120 may be dirt, rocks and other fines.

[0044] To move output 80 from evaporator 30 to separator 50, it is contemplated to utilize a pump 140. In a preferred embodiment, pump 140 may be located on the bottom of coned bottom treating tank 30, stand alone, be attached to separation tank 50, combinations thereof and so forth. It is also contemplated that more than one pump 140 may be utilized. Evaporator 30 may include an outlet and or aperture 150 such that suction end of pump 140 is connected to and or communicates with outlet 150. Invention 10 may include conduit or line 160, which may connect to discharge port of pump 140 to an inlet, opening or aperture 170 of separation tank 50. Pump 140 may be but is not limited to a diaphragm discharge pump equipped with check valves with heavy balls, coated internals and flanged connections.

[0045] Another conduit, line, pipe, aperture and or outlet 180 may move output 190 from separation tank 50 back to evaporator 30 as discussed further below. It is also understood that another pump may be utilized but not depicted to move output 190 from separator tank 50 back to evaporator 30 and it is also contemplated that output 190 from separation tank 50 may go to holding tank 20 and combinations thereof.

[0046] Separation tank 50 may be configured as a “roll-off” whereby the unit may be rolled on and or off a truck as known in the art. It is also understood that separation tank 50 may be configured to be moved in other various known methods in art and the current invention should not be considered limited to the depictions in the illustrations.

[0047] Separation tank 50 may include an access manhole 200, a top 210, a bottom 220, a door and or first end 230, a second end 240, a length 250, an interior 260. It is contemplated that first end 230 may open and use hinge(s) and or hinge system 270 to open door 230 for accessing interior 260. It may further include a wheel(s) and or wheel system 280. Interior 260 may generally have a smooth surface.

[0048] It is contemplated that separation tank 50 may further include a filter and or filter membrane 290 for allowing water to pass out of separation tank 50 while retaining larger particulates and solids in general. Filter 290 may be removable, attached to door 230, disposable, made from felt, felt like fabric, other known filter materials and so forth.

[0049] Invention 10 contemplates inlet 170 of separation tank 50 may communicate, connect, attach and so forth to trough 300 such that as output 80 from evaporator 30 enters separation tank 50 and is generally dispersed along the length 250 of interior 260. Trough 300 may be of numerous configurations such as but not limited to an open viaduct, closed and or covered viaduct with holes and or apertures along the length and so forth. Trough 300 may be generally horizontally positioned; although it is contemplated, it may be angled inside separation tank 50 as discussed further below.

[0050] Invention 10 contemplates resting tank 50 on support structure, platform, and or skid 310. Resting tank 50 may be constructed and or utilized without skid 310. In a preferred construction, resting tank 50 is set at an angle and or slope 320 such that output 190 generally utilizes gravity to move out to the line 180. Angle 320 may be about 5 degrees although greater and lesser angles are also contemplated. It is therefore contemplated that skid 310 may have a top surface 330 that is at an angle to provide angle 320 to resting tank 50. Resting tank 50 may incorporate an angle 325 such that no skid 310 is utilized. Resting tank 50 may include an angled interior surface by example.

[0051] It is contemplated that trough 300 is generally angled inside resting tank 50 to reversely correspond with angle 320. This will allow trough 300 to remain generally horizontally positioned while resting tank 50 is set at angle 320. Skid 310 may further include a drip pan 340 for catching liquids and or output 190 from outlet 180.

In Operation

[0052] Invention 10 contemplates that the addition of separation tank 50 increases operational efficiency of evaporator 30 through dilution of the return of output 190 and or water 130 with lower wastewater 40 and converting suspended solids 35 in return output 190 to dissolved form for more efficient evaporation processing. Further, invention 10 allows returning output 190 to heat the wastewater 40 feeding from stock tank 20 to encourage faster evaporation once the wastewater 40 enters the evaporation tank 30.

[0053] Separation tank 50 may dewater through crystallization initiated by temperature reduction achieved through tank design, combined with secondary nucleation via interaction with other non-salt solids, combined with gravity achieved through a sloped/angled separation tank design, combined with filter media placed at critical flow points in the separation tanks.

[0054] Therefore, invention 10 generally provides that solids 35 from wastewater 40 falls to the bottom of evaporator and or evaporation tank 30 as a result of evaporation such as but not limited to the submerged combustion process and are then removed through the use of a pump 140 from same. The discharge pump 140 may be timed and volume set to operate as needed to manage the volume and consistency of the solids continuously such as but not limited to from 5 gallons per minute to 50 gallons per minute although other amounts greater and lesser are also contemplated.

[0055] Solids 35 are then pumped from the discharge pump 140 through outlet 150 pipe or hose able to handle material heated such as but not limited to 200° Fahrenheit into the high temperature discharge pipe or hose to the separation tank 50 via inlet 170. Separation tank 50 may use time, gravity, pressure, filter media, cooling and secondary nucleation to separate free water from the solids 35.

[0056] As solids 35 settle to the bottom 220 of separation tank 50, solids 35 may form a cake like substance 45 that generally stays moist enough that it may slide out of separation tank 50 door 230 when door 230 is opened and separation tank 50 is tilted such that gravity allows substance 45 to slide out. It is understood that if substance 45 is too hardened and or dry substance 45 may not slide out as easily. Invention 10 contemplates substance 45 may meet and or exceed landfill requirements as evidenced by the passing of the paint filter test.

[0057] TDS water 130 and small solids 110 may then be returned from separation tank 50 to the staging tank and or holding tank 20 via gravity through line and or pipe 180. Pipe 180 may also be referred to as an outlet for separator 50. It is contemplated a pump may be utilized (not depicted). It is also contemplated that line 180 may go to evaporator 30 and combinations thereof. It is also contemplated to provide a lower total dissolved solids water 130 rinse that may be initiated in the return line 180 to prevent scaling.

[0058] Staging tank 20 may be designed to isolate the returned suspended solids 35 and may use air percolation 350 to agitate salt in the returned free water 130 to defeat settling and encourage return to circulation into the evaporation process. Returned suspended solids 35 may be isolated within the staging tank 20 to be quickly returned to the evaporation tank 30 via the inlet pump (not depicted) for further processing through the loop.

[0059] Holding tank 20 may include an outlet(s) 360 and an inlet 370. Evaporator 30 may have inlet(s) 380.

[0060] As needed, when solids 35 and or substance 45 are at the desired level in the separation tank 50, the separation tank 50 may be pulled with existing transportation equipment, transported to a landfill, tilted and emptied through gravity with no secondary clean out process needed. It is understood that clean out may not necessarily require tilting and that other forms of clean out may be utilized.

[0061] It is also understood that separation tank 50 may be used in combination with another separation tank 50 or others. One separation tank 50 may be hooked up to evaporator 30 while the other is emptied and so forth. It is also contemplated that evaporator 30 may continuously run while separation tank 50 is removed and then replaced. Separation tank 50 can process and separate solids continuously or intermittently as desired. It is also contemplated to run evaporator 30 and selectively utilize separator 50.

[0062] It is therefore contemplated that invention 10 may be wastewater treatment system comprising a holding tank for wastewater wherein said wastewater includes solids therein and wherein said holding tank has an inlet for receiving and an outlet for passing said wastewater; an evaporator for evaporating said wastewater, having an inlet for receiving said wastewater from said holding tank outlet, an outlet for passing said wastewater that is unevaporated and said solids from said wastewater; a separator for separating and collecting said solids from said wastewater, having an inlet for receiving from said evaporator said wastewater that is unevaporated and said solids from said wastewater; and an outlet for passing said wastewater to said holding tank inlet.

[0063] Invention 10 evaporator may be a submerged combustion evaporator, the wastewater from a producing oil and gas well, and the evaporator outlet is in communication with a pump for passing said wastewater and said solids to said separator inlet. Still further invention 10 pump may be a diaphragm pump, the separator outlet further includes a filter for filtering said wastewater before passing said wastewater to said holding tank inlet, and the filter is made from fabric.

[0064] Invention 10 may include a skid adapted to support said separator at a slope with said separator outlet at the bottom of said slope, the separator is adapted to be utilized as a roll-off for transportation, and the skid further includes a drip pan.

[0065] Changes may be made in the combinations, operations, and arrangements of the various parts and elements described herein without departing from the spirit and scope of the invention.