CN110319294B - Gas pipeline hydrate plugging and pipe replacing process - Google Patents
Gas pipeline hydrate plugging and pipe replacing process Download PDFInfo
- Publication number
- CN110319294B CN110319294B CN201910628518.2A CN201910628518A CN110319294B CN 110319294 B CN110319294 B CN 110319294B CN 201910628518 A CN201910628518 A CN 201910628518A CN 110319294 B CN110319294 B CN 110319294B
- Authority
- CN
- China
- Prior art keywords
- pipeline
- problem area
- natural gas
- ice
- sides
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
- F16L55/00—Devices or appurtenances for use in, or in connection with, pipes or pipe systems
- F16L55/16—Devices for covering leaks in pipes or hoses, e.g. hose-menders
- F16L55/1608—Devices for covering leaks in pipes or hoses, e.g. hose-menders by replacement of the damaged part of the pipe
Abstract
The invention discloses a gas pipeline hydrate plugging and pipe replacing process, which comprises the following steps: installing temperature control systems outside the pipelines at two sides of the pipeline in the problem area; pre-cooling the pipeline; tapping on a pipeline in a problem area under pressure, and installing an injection system and a monitoring system through the tapping; the injection system injects water, an accelerant and liquid nitrogen to two sides of the pipelines of the problem area, and ice and hydrate are formed in the pipelines at two sides of the pipelines of the problem area to plug the pipelines of the problem area; determining the plugging length of the hydrate and the ice to the pipeline in the problem area; processing natural gas in the blocked pipeline of the problem area by adopting a venting combustion nitrogen replacement process; intercepting and replacing the pipeline in the blocked problem area; and (5) performing blockage removing operation on the pipeline after the pipe is replaced. The invention can avoid exhausting a large amount of natural gas at the interval of the combustion valves and replacing the natural gas concentration in the pipeline between the dilution valves by using a large amount of nitrogen when the long-distance natural gas pipeline stops transporting and replacing the pipeline, thereby saving time and resources and reducing cost and safety risk.
Description
Technical Field
The invention relates to the technical field of rush repair of a long-distance natural gas pipeline by replacing a pipeline, in particular to a gas pipeline hydrate plugging and replacing process.
Background
The pipeline replacement rush repair method for stopping transportation is the most mature and widely applied method in the pipeline replacement rush repair of domestic natural gas long-distance pipelines at present. The pipeline replacement rush repair method is characterized in that natural gas in a pipeline between combustion valves is discharged under the condition that a long-distance pipeline stops conveying, and pipeline replacement rush repair operation is carried out after the concentration of the natural gas is diluted by nitrogen replacement, but a large amount of natural gas in the valve interval of the long-distance pipeline is lost, a large amount of nitrogen resources are consumed, the operation time is long, and the cost is high.
Disclosure of Invention
In order to solve the technical problems, the invention provides a hydrate plugging and pipe replacing process for a gas pipeline, which does not need to exhaust a large amount of natural gas at the interval of combustion valves and replace and dilute the concentration of the natural gas in the pipeline between the valves by using a large amount of nitrogen when a long-distance natural gas pipeline stops transporting and replacing pipes, saves time and resources, and reduces cost and safety risk.
In order to achieve the purpose, the invention adopts the technical scheme that: a gas pipeline hydrate plugging and pipe replacing process comprises the following steps:
step S10, installing temperature control systems outside the pipelines at two sides of the pipeline in the problem area;
step S20, starting a refrigeration function of the temperature control system to pre-cool the pipeline;
and step S30, tapping holes on the pipelines in the problem area under pressure, and installing an injection system and a monitoring system through the holes.
S40, the injection system injects water, accelerator and liquid nitrogen to two sides of the pipeline of the problem area, and controls the injection drop point to move from a position far away from the opening hole to a position close to the opening hole, and ice and hydrate are formed in the pipeline at two sides of the pipeline of the problem area to plug the pipeline of the problem area;
s50, measuring the blocking ranges of hydrates and ice on two sides of the pipeline in the problem area by using an ultrasonic detector, and determining the blocking lengths of the hydrates and the ice on the pipeline in the problem area;
s60, processing natural gas in the blocked problem area pipeline by adopting an emptying combustion nitrogen replacement process, detecting the concentration of the natural gas in the problem area pipeline, and determining that the concentration of the natural gas meets the requirements of intercepting and replacing the pipeline;
step S70, performing intercepting and pipe replacing operation on the blocked problem area pipeline;
and step S80, performing unblocking operation on the pipeline after pipe replacement.
The further technical scheme is that the temperature control system in the step S10 has a cooling function and a heating function.
The further technical scheme is that after the refrigeration function of the temperature control system is started in the step S20, the operation state is kept until the pipe cutting and replacing operation is finished and then the operation is closed.
The further technical scheme is that the monitoring system in the step S30 has a pressure difference monitoring function and a natural gas concentration monitoring function.
The further technical scheme is that in the step S40, the pressure difference of the gas in the pipeline in the problem area and the pipelines on the two sides of the pipeline is monitored by the monitoring system, and when the pressure difference is kept stable for a long time, the complete blocking of the hydrate and the ice on the two sides of the pipeline in the problem area is completed.
The further technical scheme is that in the step S50, when the blocking lengths of the hydrates and the ice on the two sides of the pipeline in the problem area reach or exceed the safe blocking length of the pipeline which can be completely blocked by the hydrates and the ice under the pressure of the conveying medium of the gas pipeline, the blocking lengths of the hydrates and the ice on the pipeline in the problem area are determined to meet the requirement.
The further technical scheme is that the natural gas concentration in the pipeline in the problem area is monitored through the monitoring system in the step S60, and when the natural gas concentration in the pipeline in the problem area is smaller than the safety concentration during the operation of intercepting and replacing the pipeline, the fire operation can be carried out, and the pipeline in the problem area is intercepted and replaced.
The further technical scheme is that after the pipe replacement in the step S80 is finished, the refrigeration function of the temperature control system is closed, the heating function of the temperature control system is started, the pipelines on the two sides of the new pipeline after the pipe replacement are heated, natural gas hydrate formed during the plugging of the pipeline in the problem area is decomposed into natural gas, water and ice to be melted into water, and an ultrasonic detector is used for measuring the residual plugging length of the pipeline caused by the hydrate and the ice in the pipeline until the pipeline is determined to be completely unplugged. And (4) after the pipeline is completely unplugged, removing the temperature control system.
The invention has the beneficial effects that: compared with the prior art, the invention has the following advantages:
(1) natural gas in the valve spacing of the long-distance pipeline does not need to be discharged and combusted, so that the waste of natural gas resources is greatly reduced, the safety risk is low, and the requirements on construction equipment and technology are low;
(2) the concentration of the natural gas in the long-distance pipeline is not required to be replaced and diluted by nitrogen, so that the waste of nitrogen resources is greatly reduced;
(3) the pipeline is smooth after the pipe is replaced, and no accessories are left on the pipeline;
(4) the operation time is short, and the operation cost is low.
Drawings
FIG. 1 is a schematic view of a pipeline structure of a hydrate plugging and pipe replacing process for a gas pipeline according to the present invention;
FIG. 2 is a block diagram of the process flow of the gas pipeline hydrate plugging and pipe replacement process of the present invention.
Reference numerals: a is a pipeline on one side of a problem area pipeline, B is a problem area pipeline, C is a pipeline on the other side of the problem area pipeline, 1 is a temperature control system, 2 is an injection system, and 3 is a monitoring system.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
Before the pipeline replacement and the pipeline stop in the problem area of the natural gas long-distance pipeline, preparation work is required, and the preparation work comprises the steps of determining the pipeline position of the problem area through site survey, stopping the pipeline of the long-distance pipeline, excavating an operation area, prefabricating a new pipeline and the like. In this embodiment, a hydrate plugging and pipe replacement process of a pipeline in a problem area in a gas pipeline is described based on that preparation work is completed.
As shown in fig. 1 and fig. 2, a gas pipeline hydrate plugging and pipe replacing process provided by the embodiment of the invention includes the following steps:
step S10, installing a temperature control system 1 with a refrigerating function and a heating function outside the pipeline A and the pipeline C on the two sides of the pipeline B in the problem area;
step S20, starting a refrigeration function of the temperature control system 1 to pre-cool the pipeline; after the refrigeration function of the temperature control system 1 is started, the operation state is kept until the pipe cutting and replacing operation is finished, and then the operation is closed;
step S30, tapping a hole at the position O on the pipeline B in the problem area under pressure, and installing an injection system 2 and a monitoring system 3 with a pressure difference monitoring function and a natural gas concentration monitoring function through the position O of the hole;
step S40, the injection system 2 injects water and accelerant and liquid nitrogen to two sides of the pipeline B of the problem area, and controls the injection drop point to move from the M1 point and the N1 point far away from the open hole O to the M2 point and the N2 point near the open hole O, so that ice and hydrate are formed in the M1-M2 area and the N1-N2 area on two sides of the pipeline B of the problem area to plug the pipeline B of the problem area;
monitoring the pressure difference of gas in a pipeline B of the problem area and a pipeline A on one side of the pipeline B and the pressure difference of gas in a pipeline C of the problem area and the other side of the pipeline B of the problem area through a monitoring system 3, and when the pressure difference is kept stable for a long time, completely plugging both sides of the pipeline B of the problem area by hydrates and ice is completed;
the natural gas and the water can form hydrates under the conditions of high pressure and low temperature, because sufficient high-pressure natural gas exists in the long-distance natural gas pipeline, the temperature can be quickly reduced to be far lower than the low temperature required by the formation of the hydrates by the gasification of the liquid nitrogen and the absorption of a large amount of heat, and the accelerator has an effect of promoting the formation of the hydrates, the natural gas and the water can quickly form the hydrates in the pipeline by spraying a proper amount of water into the pipeline under the combined action of the liquid nitrogen and the accelerator, the water quickly forms ice, and the plugging of the pipeline is quickly completed, so that the time can be saved, and the cost can be reduced;
s50, measuring the blocking ranges of hydrates and ice on two sides of the pipeline B in the problem area by using an ultrasonic detector, and determining the blocking lengths of the hydrates and the ice on the pipeline B in the problem area;
when the plugging lengths of hydrates and ice in M1-M2 areas and N1-N2 areas on two sides of the pipeline B in the problem area reach or exceed the safe plugging length of the pipeline when the hydrates and ice can completely plug the pipeline under the pressure of a conveying medium of the gas pipeline, determining that the plugging length of the hydrates and ice on the pipeline B in the problem area meets the requirement;
s60, processing the natural gas in the blocked problem area pipeline B by adopting an emptying combustion nitrogen replacement process, detecting the concentration of the natural gas in the problem area pipeline B, and determining that the concentration of the natural gas meets the requirements of intercepting and replacing the pipeline;
monitoring the natural gas concentration in the pipeline B in the problem area through the monitoring system 3, and when the natural gas concentration in the pipeline B in the problem area is less than the safe concentration during the pipeline intercepting and replacing operation, performing fire operation to intercept and replace the pipeline B in the problem area;
because the plugging of the hydrate to the pipeline is only carried out on two sides of the pipeline in the problem area with short length, the residual natural gas in the pipeline in the problem area with very small content only needs to be discharged and burned after the plugging is finished, the natural gas in the valve interval of the long-distance pipeline does not need to be discharged and burned, the waste of natural gas resources is greatly reduced, the safety risk is low, and the requirements on construction equipment and technology are low; the natural gas in the valve spacing of the long-distance pipeline does not need to be discharged, and the nitrogen resource does not need to be consumed to replace and dilute the concentration of the natural gas in the long-distance pipeline, so that the waste of the nitrogen resource is greatly reduced; furthermore, the natural gas in the long-distance pipeline is not subjected to emptying combustion and nitrogen replacement, so that the operation time of plugging and pipe replacing operation is short and the cost is low;
step S70, performing intercepting and pipe replacing operation on the blocked pipeline B in the problem area;
because the pipeline is blocked by the hydrate and the ice at two sides of the pipeline in the problem area and is far away from the opening position of the pipeline in the problem area, all devices connected at the opening position on the pipeline in the problem area can be intercepted during intercepting and replacing the pipeline, the pipeline is smooth after intercepting and replacing the pipeline, and no accessories are left on the pipeline;
step S80, performing deblocking operation on the pipeline after pipe replacement;
after the pipe is replaced, the refrigeration function of the temperature control system 1 is closed, the heating function of the temperature control system 1 is started, the pipeline A and the pipeline C on the two sides of the new replaced pipeline are heated, natural gas hydrate formed when the pipeline B in the problem area is plugged is decomposed into natural gas and water, ice is melted into water, and an ultrasonic detector is used for measuring the residual plugging length of the pipeline caused by the hydrate and the ice in the pipeline A and the pipeline C until the pipeline is completely unplugged. And (4) after the pipeline is completely unplugged, removing the temperature control system.
Although the present invention has been described with reference to the above embodiments, it should be understood that the present invention is not limited to the above embodiments, and those skilled in the art can make various changes and modifications without departing from the scope of the present invention.
Claims (2)
1. The gas pipeline hydrate plugging and pipe replacing process is characterized by comprising the following steps of:
step S10, installing temperature control systems outside the pipelines at two sides of the pipeline in the problem area;
step S20, starting a refrigeration function of the temperature control system to pre-cool the pipeline;
step S30, tapping holes on the pipelines in the problem area under pressure, and installing an injection system and a monitoring system through the holes;
s40, the injection system injects water, an accelerant and liquid nitrogen to two sides of the pipeline of the problem area, and controls the injection drop point to move from a position far away from the opening hole to a position close to the opening hole, and ice and natural gas hydrate are formed in the pipelines at two sides of the pipeline of the problem area to plug the pipeline of the problem area;
in the step S40, the pressure difference between the pipeline in the problem area and the gas in the pipelines on the two sides of the pipeline is monitored by the monitoring system, and when the pressure difference is kept stable for a long time, the natural gas hydrate and the ice completely block the two sides of the pipeline in the problem area;
s50, measuring the plugging ranges of the natural gas hydrate and the ice on two sides of the pipeline in the problem area by using an ultrasonic detector, and determining the plugging lengths of the natural gas hydrate and the ice on the pipeline in the problem area;
in the step S50, when the plugging lengths of the natural gas hydrate and the ice on the two sides of the pipeline in the problem area both reach or exceed the safe plugging length of the pipeline which can be completely plugged by the hydrate and the ice under the pressure of the gas transmission pipeline transmission medium, determining that the plugging lengths of the natural gas hydrate and the ice on the pipeline in the problem area meet the requirements;
s60, processing natural gas in the blocked problem area pipeline by adopting an emptying combustion nitrogen replacement process, detecting the concentration of the natural gas in the problem area pipeline, and determining that the concentration of the natural gas meets the requirements of intercepting and replacing the pipeline;
step S70, performing intercepting and pipe replacing operation on the blocked problem area pipeline;
step S80, performing deblocking operation on the pipeline after pipe replacement;
after the pipe replacement in the step S80 is finished, the refrigeration function of the temperature control system is turned off, the heating function of the temperature control system is started, the pipelines on the two sides of the new pipeline after the pipe replacement are heated, so that the natural gas hydrate formed when the pipeline in the problem area is plugged is decomposed into natural gas and water, and ice is melted into water, and the remaining plugging length of the pipeline caused by the natural gas hydrate and the ice in the pipeline is measured by using an ultrasonic detector until the pipeline is determined to be completely unplugged; and (4) after the pipeline is completely unplugged, removing the temperature control system.
2. The gas pipeline hydrate plugging and pipe replacing process as claimed in claim 1, wherein the monitoring system in the step S30 has a pressure difference monitoring function and a natural gas concentration monitoring function.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910628518.2A CN110319294B (en) | 2019-07-12 | 2019-07-12 | Gas pipeline hydrate plugging and pipe replacing process |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910628518.2A CN110319294B (en) | 2019-07-12 | 2019-07-12 | Gas pipeline hydrate plugging and pipe replacing process |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110319294A CN110319294A (en) | 2019-10-11 |
| CN110319294B true CN110319294B (en) | 2021-10-08 |
Family
ID=68122056
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910628518.2A Expired - Fee Related CN110319294B (en) | 2019-07-12 | 2019-07-12 | Gas pipeline hydrate plugging and pipe replacing process |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110319294B (en) |
Family Cites Families (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CH468589A (en) * | 1966-10-31 | 1969-02-15 | Scheidler Berthold | Method and device for the auxiliary closing of pipelines |
| US4220012A (en) * | 1976-09-13 | 1980-09-02 | Brister Beryle D | Apparatus for freezing a slug of liquid in a section of a large diameter fluid transmission line |
| DE3511726A1 (en) * | 1985-03-30 | 1986-10-02 | Immanuel 3203 Sarstedt Jeschke | Device for shutting off gas pipes |
| JP2697338B2 (en) * | 1991-03-11 | 1998-01-14 | 株式会社大林組 | Piping repair method using ice plug and ice plug generator used for the method |
| JP3551284B2 (en) * | 1996-08-28 | 2004-08-04 | 日立プラント建設株式会社 | Piping freezing method |
| JP2000065281A (en) * | 1998-08-18 | 2000-03-03 | Hitachi Plant Eng & Constr Co Ltd | Determining method for ice plug completion in piping freezing construction method |
| US20110056240A1 (en) * | 2009-09-08 | 2011-03-10 | Consolidated Edison Company Of New York, Inc. | Freeze plug system and method of operation |
| CN101865348B (en) * | 2010-05-22 | 2012-01-18 | 西南石油大学 | Freeze temporary blocking method and device for large-diameter gas pipeline |
| TWI551803B (en) * | 2010-06-15 | 2016-10-01 | 拜歐菲樂Ｉｐ有限責任公司 | Cryo-thermodynamic valve device, systems containing the cryo-thermodynamic valve device and methods using the cryo-thermodynamic valve device |
| CN205579026U (en) * | 2016-04-11 | 2016-09-14 | 单玉健 | Residential building water line refrigeration type maintenance device |
-
2019
- 2019-07-12 CN CN201910628518.2A patent/CN110319294B/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| CN110319294A (en) | 2019-10-11 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110319294B (en) | Gas pipeline hydrate plugging and pipe replacing process | |
| CN111288647A (en) | Anti-freezing gas water heater | |
| CN202001082U (en) | Steam-blowing silencing device | |
| CN214008828U (en) | Drainage monitoring device for steam pipeline | |
| CN103511044B (en) | Scr temperature control system | |
| CN110375146A (en) | Plumber's skill is changed in a kind of closure of oil pipeline hydrate | |
| CN109630241B (en) | Diesel engine side exhaust seawater cooling control method and system | |
| CN209524628U (en) | Water heater and its winterization system | |
| CN106482410A (en) | Refrigeration compressor on off control method | |
| JP2014214974A (en) | Heating system | |
| CN214948125U (en) | Intelligent lubricating system | |
| CN113112024B (en) | Prediction and control method and system for random multi-crack random expansion | |
| CN103742270A (en) | Purging pipeline monitoring method of combustor | |
| CN205024169U (en) | Adopt regenerator of nitrogen gas to get heat facility | |
| CN216894804U (en) | Air compressor wind packet drain line freeze-proof device | |
| CN102828833B (en) | For running the method for the fuel supply system of heat engine | |
| CN211635781U (en) | Steam water trap | |
| KR102394831B1 (en) | Method for Controlling Stability of Exhaust Gas Supply and Vehicle thereof | |
| CN103775214A (en) | Monitoring device for scavenging line of gas turbine | |
| CN220623224U (en) | Pipeline structure for preventing fusible medium from being blocked by crystallization | |
| CN204459141U (en) | For the Sealing of shutoff flange gasket damaged part | |
| CN219198894U (en) | Steam heating pipeline freeze-proof device and detection control system | |
| CN219208792U (en) | Tunnel water fire-fighting intelligent anti-freezing system based on micro-pressure self-circulation and fixed-point heat supply | |
| CN217612584U (en) | Steam fire extinguishing device for desulfurizing tower | |
| CN204513871U (en) | A kind of filling of the cold-producing medium for random air-conditioning refrigeration system energy-saving mechanism |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20211008 |