379results about "Insulation" patented technology

The invention discloses a concentric tube geothermal well structure capable of improving heat exchange efficiency. The concentric tube geothermal well structure comprises a first well opening section and a second well opening section. The first well opening section comprises a first casing pipe, and first well cementation cement is arranged between the inner wall of the first well opening section and the first casing pipe; the second well opening section is provided with a second casing pipe, second well cementation cement and a central casing pipe; a distance is arranged between the second casing pipe and the well wall of the second well opening section, second well cementation cement is arranged between the center casing pipe and the second casing pipe, a water stopping device is arranged at the upper end of the second well cementation cement and is of a reducing structure with the diameter sequentially increased from top to bottom, and the inner wall of the top end of the water stopping device is connected with the center casing pipe. The bottom end of the water stop device is connected with the second sleeve; a packing structure is arranged at the bottom end of the second well cementation cement, and a permeable section is arranged at the lower end of the packing structure. The invention further provides a construction method of the geothermal well structure. The structure is reliable, the heat exchange efficiency is improved, and the industrial long-term operation requirement is met.

The utility model discloses a millimeter wave deep well drilling platform, which belongs to the technical field of drilling equipment and comprises a drilling machine, a drilling rod and a gyrotron, the drilling machine and the gyrotron are arranged above the ground surface, one end of the drilling rod is connected with a drilling winch on the drilling machine, and the other end of the drilling rod extends into the ground from a drilling well. The drill rod comprises a drill rod shell and a waveguide tube in the drill rod shell, one end of the waveguide tube is communicated with the waveguide collector, the other end of the waveguide tube is provided with an opening and extends into the ground along with a drill bit of the drill rod, and the gyrotron is provided with a dynamic waveguide and movably connected with the waveguide collector through the dynamic waveguide. The dynamic waveguide comprises a waveguide leading-in pipe, a tail pipe and a plurality of groups of waveguide transmission pipes which are connected in sequence, and a plurality of millimeter wave reflection devices are arranged in the dynamic waveguide. Millimeter wave drilling is utilized, the problems of drill bit abrasion, replacement and the like in traditional drilling are solved through millimeter wave drill bit drilling, and the drilling cost is reduced.

In some implementations, a plurality of thermoelectric devices may be arranged to cool one or more components of a downhole drilling component during drilling operations. A current can be applied to one or more thermoelectric devices to generate a cooling effect. The thermoelectric devices can be located and arranged so that they cool some or all of a bottom hole assembly or components thereof, such as one or more sensors, batteries, processors, electrics, and the like. The thermoelectric devices also may be located and arranged to cool sensors, batteries, other downhole components, and / or drilling mud in a wellbore during drilling operations. A plurality of thermoelectric devices may be used to generate electric power downhole from a temperature difference. The electric power may be used to power sensors, processors, charge batteries, and be used by one or more downhole electric components, such as those in a bottom hold assembly. One or more thermal storage devices may be used with the thermoelectric devices to store thermal energy for use when needed. A control system may be used to control the activation and / or deactivation of one or more thermoelectric devices to provide cooling when desired.

The invention discloses a seabed shallow casing section thermal insulation structure for polar region supercritical carbon dioxide drilling, which comprises a casing, a thermal insulation coating, a protective coating, an annular cement slurry layer, an electric heating pipe, a sensor module, a wireless conductive module, a ground system and a seabed wireless transmission module, and is characterized in that the electric heating pipe is fixed on the outer wall of the casing through a hoop; the outer wall of the casing pipe is sequentially coated with a heat preservation coating, a protective coating and an annular cement paste layer from inside to outside, the wireless conductive module is integrated at the end of the casing pipe, and the ground system comprises a ground data acquisition system and a ground control center. The sea surface platform is provided with a ground data acquisition system and a ground control center which are connected with the seabed wireless transmission module through an umbilical cable, and temperature and pressure data acquired by the sensor module are uploaded to the ground control center. According to the invention, the problems of rapid heat loss, annular air channeling, casing mechanical property degradation, poor drilling fluid fluidity and the like of the seabed shallow casing section in the polar region extreme low-temperature environment are solved.

The invention discloses self-adaptive variable-diameter drilling equipment for a high and cold frozen soil region and a stable-temperature construction method, and relates to the technical field of constructional engineering construction equipment, in particular to the self-adaptive variable-diameter drilling equipment for the high and cold frozen soil region, the self-adaptive variable-diameter drilling equipment comprises a main body, and the top of the main body is fixedly connected with a drilling assembly; a multi-blade structure is utilized, each blade is provided with an independent electric heating wire, the electric heating wires can preheat the blades in the drilling process, the blades are prevented from being embrittled due to low temperature, the service life of the drill bit is prolonged, the multiple telescopic auxiliary rotary drill bits are evenly distributed around the main drill bit, and the drilling efficiency is improved. The telescopic rod controls the auxiliary rotary drill bit to automatically adjust the telescopic length of the auxiliary rotary drill bit according to the hardness of the frozen soil layer and the drilling depth, so that the total diameter of the drill bit is changed to meet the drilling requirements of different diameters.

The invention belongs to the technical field of oil exploitation, and particularly discloses a sectional type electric heating auxiliary thickened oil exploitation system and method.The system comprises a power supply station, a voltage transformation power regulation cabinet, a junction box, an injection and production pry, a power supply section cable, a cable connector, a wellhead, a production sleeve, a main pipe, an auxiliary pipe, a heating section cable, a hanger and a screen pipe, the production sleeve is connected with a wellhead, the hanger is located in the production sleeve, the screen pipe is connected with the production sleeve through the hanger, the main pipe is located in the production sleeve, the auxiliary pipe is located in the production sleeve and the screen pipe, and the heating section cable is located in the auxiliary pipe. The heating section cable is composed of a central supporting line, a plurality of heating modules, a plurality of module spacing layers and a metal sheath from inside to outside, the plurality of heating modules are uniformly connected to the central supporting line in series, the plurality of module spacing layers are located between two adjacent heating modules, and each heating module is integrated with an SIC power switch. And the heating section cable is connected with the power supply section cable through a cable joint.

Systems and methods disclosed herein may comprise a bottom hole assembly; and a cable disposed in the wellbore. In examples, the cable may comprise a superconducting material configured to provide at least power to the bottom hole assembly; one or more liquid supply channels configured to supply a fluid to reduce temperature of the superconducting material; and one or more liquid return channels. Further, cryogenic liquid may be pumped through the liquid supply channels.

The utility model relates to the field of oilfield development, in particular to a double-hollow sucker rod heating device which comprises a heating tank, a sucker rod assembly, a stirring assembly, a heating assembly, a flow guide pipe, a threaded sleeve, a feeding hopper, a first hydraulic controller and a liquid discharging pipe. The heat conduction layer and the heat preservation and insulation layer are arranged in the inner pipe and the outer pipe of the sucker rod respectively, heat transfer between a heat carrier and the sucker rod can be enhanced through the heat conduction layer, it is ensured that heat can be efficiently transferred to the underground, heat loss of the heat carrier in the flowing process can be reduced through cooperation of the heat preservation and insulation layer, and the service life of the sucker rod is prolonged. The heating assembly capable of sensing the temperature of the heating carrier in the heating device in real time is arranged, and the heating temperature can be flexibly adjusted according to the actual temperature change of the heat carrier liquid to achieve rapid temperature rise of the heat carrier liquid; and the stirring assembly is arranged, so that the heat carrier liquid flowing back into the heating device can be quickly and uniformly stirred in a rotary stirring mode to accelerate temperature rise.

The well mouth electromagnetic heating device comprises a shell, the shell is of a hollow structure, an insulating layer is fixedly installed on the inner wall of the shell, a spiral electromagnetic induction coil is fixedly installed on the inner wall of the insulating layer, an inner ring of the electromagnetic induction coil is installed on a heat preservation layer in a winding mode, and a heating tank is fixedly installed on the inner wall of the heat preservation layer. The stirring column and the metal rod rotate along with the rotating rod to stir liquid in the heating tank, so that different parts of the liquid are fully mixed, the metal rod generates induction heat under the action of a magnetic field, the heat can be diffused in the liquid more quickly and uniformly, the phenomenon of temperature stratification is avoided, and the heating uniformity is further improved. Cleaning liquid is injected into the first channel of the rotating rod through the connector, the cleaning liquid is sprayed out of the nozzle through the second channel, the sprayed cleaning liquid comprehensively cleans the interior of the heating tank, meanwhile, the scraping plate can scrape the inner wall of the heating tank in the stirring process, and impurities or precipitates in the liquid are prevented from being attached to the inner wall.

Igniter assemblies for use with setting tools are disclosed. The igniter assemblies have an electronic heating element disposed adjacent to an energetic material within a setting tool. In some embodiments, the electronic heating element is a resistor or a PCB mounted resistor. Electrical connections are attached to the heating element to provide electrical current to activate the heating element. In some instances, the electrical heating element is disposed onto an insulator cap that is coupled to a pressure block attached to the setting tool, and in some instances the electronic heating element is attached to a non-explosive portion and the energetic material is disposed within an explosive portion. When the non-explosive portion and the explosive portion are assembled, the electronic heating element is adjacent to the energetic material. Other assemblies are described.

An electric submersible pump includes a heat exchanger, a shaft comprising an axial bore, and a motor, which includes a rotor rotationally coupled to the shaft, a stator concentrically disposed with respect to the rotor, and a journal bearing disposed between the stator and the shaft. There is a gap between the rotor and the stator. The electric submersible pump further includes a first pump mechanically coupled to the shaft and configured to pump production fluid through a tubular, and a second pump mechanically coupled to the shaft and configured to pump coolant through the axial bore, the gap, and the heat exchanger. The heat exchanger transfers heat from the coolant to the production fluid to cool the motor.

A system and method are provided for installing a well for a borehole heat exchanger. The method includes drilling a hole formation to a predetermined depth relative to a ground surface, including operating a bottomhole assembly (BHA) including a drill bit supported at a bottom end of a cable positioned within a flexible tube. After drilling the hole formation to a predetermined depth, the BHA is retracted through the flexible tube to remove the BHA from the hole formation while the flexible tube remains in the hole formation.

The utility model relates to the technical field of oil extraction pipes, in particular to an injection-production pipe for an electric heating heavy oil well. The injection-production pipe of the electric heating heavy oil well comprises an injection-production well pipe body, the outer wall of the injection-production well pipe body is sleeved with symmetrically-distributed supporting discs, and heat preservation assemblies are installed on the supporting discs and the injection-production well pipe body. According to the injection-production pipe of the electric heating heavy oil well, in the using process, the heat preservation barrel arranged outside the end opening of the injection-production well pipe in the heat preservation assembly in the sleeving mode can cover the end of the injection-production well pipe for heat preservation, and therefore the probability that the end opening of the injection-production well pipe is frozen when the air temperature is relatively low in winter can be reduced, and the service life of the injection-production well pipe is prolonged. And the influence on later oil extraction is reduced.

The invention relates to a process for removing an obstruction (13) caused by gas hydrates or water ice from the tubing (12) of a hydrocarbon production or injection well or a riser. The process comprises passing a microwave generating and emitting tool (5) on wireline (8) down the tubing (12) and supplying electrical power to the tool via the wireline (8) or from a battery to produce microwave energy and direct it to the gas hydrate and / or water ice deposit (13), thereby melting deposit and unblocking the well.

The invention discloses a method for establishing initial conditions of a gas reservoir through uniform initialization of a heterogeneous large rock plate model, and belongs to the technical field of gas reservoir development. On the basis that a conventional rock plate is provided with injection and production well inlets and outlets, the two sieve pipe injection channels are additionally arranged, the two ends of the sieve pipe are connected through the pipeline, and fluid can be injected into the sieve pipe; plugging or heating plugging removal operation is achieved by injecting a plugging agent into the four pipelines in good time, namely, an injection well and a production well are plugged firstly, formation water is injected through a screen pipe to make a rock plate saturated, and then formation water in the rock plate is displaced through gas injection of the screen pipe; the screen pipe is plugged, and a plugging removal injection and production well preparation experiment is carried out; the rock plate reaches an initial state of a gas drive / depletion experiment; the problem that the screen pipe becomes a high-permeability channel to affect a gas drive experiment and cause distortion of gas drive experiment data is avoided, the accuracy of a large flat plate model longitudinal heterogeneous gas reservoir water invasion failure or constant volume failure evaluation experiment can be improved, and the method has important significance on compact reservoir transformation and effective development.

An electric submersible pump includes a heat exchanger, a shaft comprising an axial bore, and a motor, which includes a rotor rotationally coupled to the shaft, a stator concentrically disposed with respect to the rotor, and a journal bearing disposed between the stator and the shaft. There is a gap between the rotor and the stator. The electric submersible pump further includes a first pump mechanically coupled to the shaft and configured to pump production fluid through a tubular, and a second pump mechanically coupled to the shaft and configured to pump coolant through the axial bore, the gap, and the heat exchanger. The heat exchanger transfers heat from the coolant to the production fluid to cool the motor.

A system for recovering ammonia from an endothermic reaction in a subsurface formation may comprise a subsurface formation; a wellbore fluidly connected to the subsurface formation; a tubing string positioned within the wellbore, wherein the wellbore and an exterior of the tubing string together define a wellbore annulus; a wellhead comprising one or more injection lines and one or more return lines fluidly connected to the wellbore; one or more fluid injection pumps configured to supply an endothermic fluid composition to the subsurface formation through the one or more injection lines and the tubing string, the endothermic fluid composition operable to form ammonia when reacted; and one or more ammonia retention vessels fluidly connected to the return lines for receiving the ammonia through the wellbore annulus.

A wellbore is drilled in a subterranean zone with a drill bit of a drilling string. The drilling string includes tubing and a fluid separator uphole of the drill bit. While drilling, a drilling fluid is flowed through an interior of the drilling string and through the fluid separator. The fluid separator separates, from the drilling fluid, a fluid stream having a higher water-to-oil ratio than a remainder of the drilling fluid Uphole of the drill bit, the fluid stream is diverted from the fluid separator to an annulus around the exterior of the drilling string based on a specified temperature of a drilling string component while the remainder of the drilling fluid flows from the fluid separator to the drill bit.

The present application relates to the technical field of soft coal seam drilling, and discloses an intelligent control drill rod and blowout hole device for soft coal seam drilling, which comprises a front-end sensing unit, a relay sensing unit, a hydraulic servo motor, a frequency converter, a shape memory alloy framework, a thermal-responsive polymer expansion gel layer and a control unit. The device can expand to 3 times the original diameter within 2 seconds through thermal triggering, forming a multi-stage labyrinth seal. The control unit is installed with an embedded AI chip to run an LSTM pressure time sequence prediction model, and combines temperature and vibration multi-source data fusion to judge the blowout risk level, solving the problems of lack of real-time gas pressure dynamic monitoring capability of traditional drill rods, reliance on artificial experience to judge blowout risk, and response lag. The single position pressure sensor is easily disturbed by local rock layer mutation, has a high false alarm rate, and cannot distinguish between normal pressure fluctuations and blowout precursors, so the device realizes early blowout warning and actively suppresses blowout accidents.

The utility model relates to the field of gas field production, in particular to a heatable throttle valve for a gas well, which comprises a throttle valve respectively communicated with an inlet pipeline and an outlet pipeline. The electromagnetic induction coil is arranged on the periphery of the throttling valve; the controller is in communication connection with the electromagnetic induction coil, and the controller can control the electromagnetic induction coil to be opened or closed. The throttling valve is directly heated through the electromagnetic induction coil, the heating efficiency is high, it can be ensured that the throttling valve is not blocked by ice in high-pressure gas well large-pressure-difference pressure reduction throttling or low-temperature weather in winter, and the normal use requirement is met.

The present invention relates to an annular barrier for expansion in an annulus between a first well tubular metal structure and an inner face of a borehole or a second well tubular metal structure for providing zone isolation between a first zone and a second zone of the annulus, the annular barrier having a first axial extension, where the annular barrier comprises a tubular metal part for mounting as part of the first well tubular metal structure, the tubular metal part having an outer face, an expandable metal sleeve surrounding the tubular metal part and having an outer face facing towards the inner face of the borehole or the second well tubular metal structure and an inner face facing the outer face of the tubular metal part, a second axial extension along the first axial extension, and each end of the expandable metal sleeve being connected with the tubular metal part, an annular space between the expandable metal sleeve and the tubular metal part, an expansion opening in the tubular metal part through which fluid may enter the annular space in order to expand the expandable metal sleeve, and wherein the annular barrier further comprises a eutectic material and / or a bentonite material which in a first condition is arranged on the outer face of the tubular metal part in a first axial position different from the second axial extension of the expandable metal sleeve, and in a second condition and a second axial position the eutectic material and / or a bentonite material abuts a face of the expandable metal sleeve, and in an intermediate condition the eutectic material and / or a bentonite material is positioned between the first axial position and the second axial position. The invention also relates to a downhole system comprising the annular barrier and a downhole tool string comprising a heating unit for heating the eutectic material and / or a bentonite material.

The invention discloses a magnetothermal refrigeration system and method for an underground while-drilling circuit, and relates to the technical field of thermal management of the underground while-drilling circuit, the system comprises a magnetothermal working medium module, a magnetic field generation and modulation module and a closed heat transfer fluid loop, and the closed heat transfer fluid loop is in thermal contact connection with the underground while-drilling circuit and the magnetothermal working medium module; the interior of the magnetocaloric working medium module is filled with a magnetocaloric material; the magnetic field generation and modulation module is used for applying a periodically changing magnetic field to the magnetocaloric working medium module, so that a magnetocaloric material in the magnetocaloric working medium module is periodically magnetized and demagnetized; the closed heat transfer fluid loop is used for completing heat transfer and transfer of an underground while-drilling circuit and the magnetic heat working medium module. By constructing the magnetothermal working medium module, the magnetic field generation and modulation module and the closed heat transfer fluid loop, the advantages that the magnetothermal effect theory is high in efficiency and free of spontaneous heating accumulation are utilized, and the long-term effectiveness and accuracy of underground while-drilling circuit heat management are improved.

A thermal system includes a borehole heat exchanger, a facility having a peak heating load, a data center including at least one heat generating electronic component, and a ground-source heat pump. The data center, the borehole heat exchanger, and the ground-source heat pump are connected in a dynamic downhole fluid circuit with a flow of a downhole fluid. The dynamic downhole fluid circuit is configured to reject heat from the data center to the facility and to the BHE, and a power capacity of the data center is less than the peak heating load of the facility.

The invention discloses a wellhead throttling anti-freezing and anti-blocking device and method for a carbon dioxide flooding well, and relates to the technical field of carbon dioxide flooding wells. Wherein the oil nozzle comprises a first-stage oil nozzle and a second-stage oil nozzle arranged at the upper part in the heating box which are connected; the inlet end of the primary oil nozzle is connected with an outlet oil nozzle sleeve of the Christmas tree; the outlet end of the primary oil nozzle is connected with the inlet end of the secondary oil nozzle; the outlet end of the secondary oil nozzle is connected with the inlet end of the coil in the heating box; the outlet end of the coil penetrates out of the heating box and is connected with a gathering pipe communicated with the lower side of an oil outlet pipe of the Christmas tree. The method is a production management method which can adapt to the production change rule of the carbon dioxide flooding well on the premise that the conventional carbon dioxide flooding well mouth process and the electric power facility design are not rebuilt and expanded, and is economical.

The utility model discloses a wellhead high-temperature fluid cooling device which comprises a shell. The first partition plates are arranged in the shell in parallel at intervals, and the upper ends and the lower ends of the first partition plates are fixedly connected to the top plate and the bottom plate of the shell correspondingly; the second partition plates are arranged in the shell in parallel at intervals, and the second partition plates and the first partition plates are arranged in a crossed mode; the upper end of the second partition plate is fixedly connected to the top plate of the shell, and a gap is formed between the lower end and the bottom plate of the shell; the plurality of third partition plates are arranged in the shell, are parallel to the second partition plates and are arranged at intervals; the lower end of the third partition plate is fixedly connected to the bottom plate of the shell, and a gap is formed between the upper end and the top plate of the shell; the petroleum flowing pipeline comprises multiple layers of pipeline units which are arranged at intervals in the height direction of the shell, and the pipeline units are reciprocating bending pipelines parallel to a bottom plate of the shell; the cooling water pipe is used for introducing cooling water into the shell; and the cooling water outflow pipe is used for discharging the cooling water after heat exchange in the shell.

The application discloses a "three plugging and one injection" low-temperature epoxy propane efficient gasification fracturing permeability improvement device and method, which comprises five functions of efficient hole sealing, hole cleaning and dust blocking, efficient heating, automatic control and safety and reliability. The device adopts a "three plugging and one injection + slip" technology to block the new fractures around the drilling hole, so that the artificial induced coal seam gas directional flow is realized. The coal seam is fractured by the high-pressure and low-temperature gas generated by the epoxy propane. The coal seam is fractured by the way that the low-temperature epoxy propane is injected into the fractured hole to make the low-temperature epoxy propane gasify. After the high-pressure gas enters the coal body, the high-pressure gas is uniformly distributed in the coal seam, the internal fractures of the coal body are promoted to develop, expand and penetrate, and the permeability of the coal seam is uniformly increased, so that the purpose of efficient fracturing and permeability improvement is realized, and the problem of significant disasters caused by gas over-limit is solved.

The utility model relates to a drilling tool deviation prevention device for a coring drill, which comprises a base capable of being arranged on the ground surface. The lower surface of the base is provided with a positioning insertion column assembly which can be inserted into the stratum to assist in limiting the position coordinates of the base on the earth surface. The freezing reinforcing assembly can be inserted into a stratum in a mode of surrounding a drill hole to form a frozen soil block surrounding the drill hole, and the anti-deviation assembly can be inserted into the expanded drill hole to limit and support a drilling tool in the drill hole. A plurality of refrigeration arc plates of the freezing reinforcing assembly are annularly arranged on an installation annular plate at intervals in the mode of surrounding the anti-deviation assembly, and the installation annular plate is detachably embedded in the lower surface of the base. According to the utility model, the stability and the limiting strength of a soil body can be improved by freezing a soil layer, and meanwhile, the drill rod is elastically buffered and pulled by utilizing the limiting support of the anti-deviation structure, so that the two-dimensional constraint of the drilling tool is realized.

The invention discloses an anti-waxing electric heating carbon fiber continuous sucker rod, belongs to the technical field of sucker rods, and aims to solve the problems that the sucker rod is heated by only depending on a heating cable to prevent wax precipitation of crude oil, such as power supply failure and insufficient power of the cable, a deposited wax layer can be hardened, so that softening is difficult in subsequent heating, extra hot washing or mechanical wax removal is needed, and the service life of the sucker rod is shortened. In order to solve the problems that an existing sucker rod is not provided with a heating cable, the heating cable only can prevent wax and cannot deal with scaling on the surface of the sucker rod, the invention comprises a sucker rod main body and a linkage mechanism, and the linkage mechanism used for automatic scraping is arranged in the middle of the inner side of the sucker rod main body. The outer surfaces of a bottom oil rod and a connecting oil rod can be scraped and cleaned through rotation of the scraper, the possibility of crude oil wax precipitation can be greatly reduced through cooperation of the scraper and heating of a heating cable on a sucker rod body, shutdown or additional operation is not needed, wax removal during operation is achieved, the device adapts to the working condition of continuous crude oil wax precipitation, the temperature influence is avoided, and the service life of the device is prolonged. The wax removal stability can be ensured.

The utility model discloses a vacuum negative pressure oil extraction device for an oil well, and belongs to the field of oil well exploitation. The vacuum negative pressure oil extraction device for the oil well comprises a heat dissipation body, a Teflon heating pipe is arranged in the heat dissipation body, heat conduction blocks are transversely and evenly distributed on the outer portion of the heat dissipation body, and adaptive grooves are formed in the outer portions of the heat conduction blocks in a sunken mode. The heating device solves the problems that the outer portion of an existing pipeline is prone to sinking and protruding, and the heating device in the patent cannot be well attached to the appearance of the pipeline, and the heat conduction block transversely slides on the outer portion of the heat dissipation body and is adjusted to make contact with the vacuum negative pressure oil extraction pipeline. When the outside of the vacuum negative-pressure oil extraction pipeline protrudes to influence the heat conduction block, the heat conduction block slides outside the heat dissipation body and can be prevented from colliding with the protruding position, and contact is avoided.

A system for recovering ammonia from an endothermic reaction in a subsurface formation may comprise a subsurface formation; a wellbore fluidly connected to the subsurface formation; a tubing string positioned within the wellbore, wherein the wellbore and an exterior of the tubing string together define a wellbore annulus; a wellhead comprising one or more injection lines and one or more return lines fluidly connected to the wellbore; one or more fluid injection pumps configured to supply an endothermic fluid composition to the subsurface formation through the one or more injection lines and the tubing string, the endothermic fluid composition operable to form ammonia when reacted; and one or more ammonia retention vessels fluidly connected to the return lines for receiving the ammonia through the wellbore annulus.