Process Pumps and Related Methods of Treating a Process Line

This application is a divisional application of and claims the benefit of priority to U.S. application Ser. No. 17/937,687, filed on Oct. 3, 2022, the contents of which are hereby incorporated by reference.

This disclosure relates to dual-cylinder piston pumps and related methods of chemically treating a fluid within a process line.

Hydrocarbon operations facilities includes multiple chemical injection skids for effecting process treatment requirements. Such skids consume a significant amount of electrical energy over the course of carrying out treatment processes. Options for chemical injection include manual injection processes and pump-based injection processes. These conventional processes come with several disadvantages, such as high expenses of pump injection processes that are fully dependent on electrical energy sources and a low effectiveness of manual injection processes as a result of lengthy set-up processes and operator inefficiencies.

This disclosure relates to dual-cylinder piston pumps and related methods of hydraulically operating such a pump to chemically treat a fluid within a process line. The pump can be operated without an electric motor and thereby operates with a relatively low-energy consumption.

In one aspect, a method of treating a fluid within a process line includes flowing a treatment chemical and a first volume of the fluid into an injection chamber of a process pump, exerting an upward force on a lower cylinder of a piston of the process pump with a mixture of the treatment chemical and the first volume of the fluid within the injection chamber, exerting a downward force on an upper cylinder of the piston with a second volume of the fluid, and transmitting the downward force to the lower cylinder of the piston to force the mixture out of the injection chamber and into the process line.

Embodiments may provide one or more of the following features.

In some embodiments, the method further includes forcing a third volume of the fluid within the pumping chamber into a relief line and flowing the third volume of fluid into an outlet line.

In some embodiments, the method further includes flowing the second volume of fluid into the pumping chamber.

In some embodiments, the method further includes lengthening a positioning spring attached to the upper cylinder from a collapsed configuration to an extended configuration.

In some embodiments, the method further includes reducing an upper volume of an upper pressure transmission chamber adjacent the upper cylinder.

In some embodiments, the method further includes increasing a lower volume of a lower pressure transmission chamber adjacent the lower cylinder.

In some embodiments, the method further includes flowing a pressure transmission fluid from the upper transmission chamber to the lower transmission chamber.

In some embodiments, the pressure transmission fluid includes oil.

In some embodiments, the method further includes automatically actuating two or more valves that are in fluid communication with the process pump.

In some embodiments, the method further includes simultaneously actuating two or more valves that are in fluid communication with the process pump.

In another aspect, a fluid processing system includes a process pump. The process pump includes a housing including an upper chamber wall and a lower chamber wall and a piston that is movable within the housing. The piston includes a shaft, a lower cylinder fixed to a lower end of the shaft and disposed within the lower chamber wall, and an upper cylinder slidably coupled to an upper end of the shaft and disposed within the upper chamber wall.

Embodiments may provide one or more of the following features.

In some embodiments, the process pump further includes a positioning spring that is attached to the upper end of the shaft and to an upper surface of the upper cylinder.

In some embodiments, the positioning spring is biased to a collapsed configuration and is configured to lengthen to an extended configuration in response to a downward force directed on the upper cylinder.

In some embodiments, the upper cylinder and the lower chamber wall together form an upper pressure transmission chamber, and the lower chamber wall and the lower cylinder together form a lower pressure transmission chamber.

In some embodiments, the process pump further includes a conduit that extends between the upper and lower pressure transmission chambers

In some embodiments, the upper and lower pressure transmission chambers contain a pressure transmission fluid.

In some embodiments, the fluid processing system further includes a chemical tank, a process line containing a fluid to be treated by the process pump, and a fluid circuit by which the chemical tank fluidly communicates with the process pump and by which the process pump fluidly communicates with the process line.

In some embodiments, the fluid processing system further includes multiple automated valves positioned across the fluid circuit.

In some embodiments, the process pump is configured to pump a dose of a treatment chemical from the chemical tank through the fluid circuit and into the process line. In another aspect, a process pump includes a housing including an upper chamber wall and a lower chamber wall and a piston that is movable within the housing. The piston includes a shaft, a lower cylinder fixed to a lower end of the shaft and disposed within the lower chamber wall, and an upper cylinder slidably coupled to an upper end of the shaft and disposed within the upper chamber wall.

The details of one or more embodiments are set forth in the accompanying drawings and description. Other features, aspects, and advantages of the embodiments will become apparent from the description, drawings, and claims.

illustrates an example fluid processing system(e.g., a chemical injection skid) within an oil and gas processing facility. The fluid processing systemincludes a process linethrough which a fluid(e.g., industrial water) flows to various processing stations within the processing facility, a chemical tankthat stores a treatment chemical, and a process pumpthat pumps the treatment chemicalinto the process linefor treating the fluid. Example treatment chemicalsthat may be stored in the chemical tankinclude hypochlorite and other chemicals. The chemical tankis equipped with a level indicatorthat monitors a level of the treatment chemicalwithin the chemical tankand a gaugethat monitors a pressure of the treatment chemical.

The fluid processing systemalso includes several additional fluid lines by which the fluidand the chemicalare circulated throughout a fluid circuit. The fluid lines include an inlet line, an inlet line, a pressurization line, a chemical line, a chemical line, a relief line, and an outlet line. The fluid processing systemfurther includes several control valves (e.g., dosing valves CV, CV, CV, and CV) that are equipped with respective pressure and flow sensors, several check valves (e.g., one-way valves CHA, CHB, CH, CHA, CHB, and CH), and a relief valve RV. The fluid processing systemaccordingly includes a controllerthat controls opening and closing of the various valves in a synchronized manner to achieve a system logic based on signals received from the pressure sensors.

Referring to, the process pumpis designed to efficiently pump (e.g., dose) the treatment chemicalinto the process linewithout an associated electrical motor and any power that would otherwise be delivered from such a motor. The process pumpoperates automatically as a result of actions of the control valves. The process pumpincludes a housingand a dual-cylinder pistonpositioned within the housing. The housingincludes an upper chamber walland a lower chamber wall. The upper chamber wallincludes an upper side walland an upper ceiling wall. The lower chamber wallincludes a lower side wall, a lower ceiling wall, and a bottom wall.

The pistonincludes a shaft, a lower cylinderthat is fixed to a lower end of the shaft, an upper cylinderthat is slidably coupled to an upper endof the shaft, and a positioning springlocated at the upper end. The process pumpfurther includes a plug valve, a pressure relief port, an inlet port, and an inlet portlocated within the upper ceiling wall. The shaftextends through an openingin the lower ceiling wall. The lower side wallincludes an inlet port, an outlet port, and a lower pressure transmission port.

The lower cylinder, the lower side wall, and the bottom walltogether define an injection chamberthat receives the treatment chemicaland the fluid. The upper cylinder, the upper side wall, and the upper ceiling walltogether define a pumping chamberthat receives fluidfrom the inlet lineto force the pistonin a downward direction. The positioning springis attached to a stopperat the upper endof shaftand to an upper surface of the upper cylinder. Therefore, a fully extended length of the positioning springdefines a total distance by which the upper cylindercan move downward from the upper endof the shaft. The process pumpis equipped with a position sensorthat monitors a position of the upper cylinderduring delivery of a chemical dose to the injection chamber.

The lower side wall, the lower cylinder, and the lower ceiling walltogether define a lower pressure transmission chambercontaining a pressure transmission fluid(e.g., transmission oil). The upper side wall, the upper cylinder, and the lower ceiling walltogether define an upper pressure transmission chambercontaining the pressure transmission fluid(e.g., transmission oil). Accordingly, the upper side wallincludes an upper pressure transmission port. A pressure transmission conduitextends between the lower and upper pressure transmission ports,. The pressure transmission conduitis available to collect an overflow of pressure transmission fluidto accommodate a reduction in total volume of the lower and upper pressure transmission chambers,.

sequentially illustrate a smooth, cyclic process for treating the fluidwithin the process line(e.g., a chemical treatment cycle) by operating the process pump.illustrates a first stage of the process. During the first stage, a predetermined (e.g., preset) volume of fluidflows into the inlet lines,from the process linethrough a fluid circuit inlet. The fluidflows to CVand CV, which are closed during the first stage. Additionally, a predetermined volume (e.g., a preset dose) of treatment chemicalflows into the chemical lines,from the chemical tankthrough CV, CHA, and CHB, which are open during the first stage. The treatment chemicalflows further into the injection chamberand to CV, which is closed during the first stage. The plug valveis also closed during the first stage, which prevents fluidwithin the pumping chamberfrom flowing out of the pumping chamberduring the first stage.

illustrates a second stage of the process. During the second stage, CVcloses, CVopens, the plug valveopens, and RVopens simultaneously (e.g., synchronously) upon receiving respective instructions from the controller. Accordingly, the fluidin the inlet lineand the treatment chemicalin the chemical lineflow through CVand CHand CHA, respectively, into the chemical line, through CHB, and into the injection chamber. Within the injection chamber, a mixtureof the treatment chemicaland the fluid(e.g., having a volume larger than that of the initial dose of the treatment chemicalalone) exerts an upward force on a lower surface of the lower cylinder. Because a fluid pressure within the pressure transmission chambers,and the pumping chamberare all substantially equal, the upward directed force causes the entire pistonto move upward in a fixed configuration of the lower and upper cylinders,.

Upward movement of the pistonincreases a volume of the injection chamberand decreases a volume of the pumping chamberby substantially the same amount. The decreased volume of the pumping chamberforces the fluidto flow out of the pumping chamber, through the pressure relief portand into the relief line. The fluidflows to CHB, which is closed during the second stage. Volumes of the lower and upper pressure transmission chambers,remain substantially unchanged during the second stage of the process.

illustrates a third stage of the process. During the third stage, CVcloses, CHB closes, CVopens, the plug valvecloses, the inlet ports,open, CHB opens, and CVopens simultaneously (e.g., synchronously) upon receiving respective instructions from the controller. Accordingly, fluidin the inlet lines,flows through the inlet port, the pressurization line, and the inlet portinto the pumping chamber. The fluidis confined in the pumping chambersuch that a fluid pressure within the pumping chamberincreases and the fluidexerts a downward force on an upper surface of the upper cylinder.

The force causes the upper cylinderto slide downward along the shaftfrom the upper endof the shaftby the total length of the positioning springin its fully extended configuration. Thus, downward movement of the upper cylindercauses the positioning springto extend from a collapsed, biased configuration (e.g., shown in) to the fully extended configuration (e.g., shown in). Downward movement of the upper cylinderaccordingly increases the volume of the pumping chamberand decreases volume of the upper pressure transmission chamber. Compression of the upper pressure transmission chambercauses the pressure transmission fluidwithin the upper pressure transmission chamberto overflow into the pressure transmission conduitand further into the lower transmission chamber. This flow increases the volume of the lower pressure transmission chamberto and accordingly exerts a downward force on an upper surface of the lower cylinder.

The downward force on the lower cylinderforces the mixtureout of the injection chamber, through CVand CH, and into the outlet line. In this manner, the pistonoperates like a plunger in response to dynamic pressures within the process pump. Fluidin the relief linealso flows through CHinto the outlet line. From the outlet line, the mixture(e.g., including the treatment chemical) flows through the fluid circuit outletinto the process lineto treat the fluidin the process line.

The process may then be repeated as many times as necessary to achieve a desired level of chemical treatment within the process line(e.g., a desired number or frequency of doses to the fluidwithin the process line. Throughout the process, the level and the pressure of the treatment chemicalwithin the chemical tankare respectively monitored by the level indicatorand the gaugeto ensure that the treatment chemicalremains at a substantially low pressure. In some embodiments, the pressure of the treatment chemicalwithin the chemical tankis maintained between about 101.3 kilopascals (kPa) and about 344.8 Pa.

Utilizing hydraulic mechanical actuation of the process pumpavoids consumption of significant electrical power that would otherwise need to be produced by a motor to actuate a conventional treatment pump for dosing a process line with a chemical treatment. For example, carrying out the process illustrated into divert a stream of fluidfrom the process lineinto the fluid circuiteffectively provides the process pumpwith a self-renewing energy source. In this manner, a design and an implementation of the process pumpresults in a significant reduction in the number of components needed to treat a process line and a related operational cost savings. Furthermore, eliminating power sources (e.g., such as a motor) correspondingly eliminates carbon emissions that would otherwise accompany the utilization of such power sources. Additionally, owing to an automated functioning of the process pumpprovided by the control valves, human involvement in the chemical treatment is minimized and an efficiency of the chemical dosing is maximized.

is a flow chart illustrating an example methodof treating a fluid (e.g., the fluid) within a process line (e.g., the process line). In some embodiments, the methodincludes a stepfor flowing a treatment chemical (e.g., the treatment chemical) and a first volume of the fluid into an injection chamber (e.g., the injection chamber) of a process pump (e.g., the process pump). In some embodiments, the methodincludes a stepfor exerting an upward force on a lower cylinder (e.g., the lower cylinder) of a piston (e.g., the piston) of the process pump with a mixture (e.g., the mixture) of the treatment chemical and the first volume of the fluid within the injection chamber.). In some embodiments, the methodincludes a stepfor exerting a downward force on an upper cylinder (e.g., the upper cylinder) of the piston with a second volume of the fluid. In some embodiments, the methodincludes a stepfor transmitting the downward force to the lower cylinder of the piston to force the mixture out of the injection chamber and into the process line.

While the fluid processing systemand the process pumphave been described and illustrated with respect to certain dimensions, sizes, shapes, arrangements, materials, and methods, in some embodiments, a system or a pump that is otherwise substantially similar in construction and function to the fluid processing systemor the process pumpmay include one or more different dimensions, sizes, shapes, arrangements, configurations, and materials or may be utilized according to different methods.

Accordingly, other embodiments are also within the scope of the following claims.