CN104907292A

CN104907292A - High sour gas field gas gathering station sand flushing cleaning process

Info

Publication number: CN104907292A
Application number: CN201510174731.2A
Authority: CN
Inventors: 张波
Original assignee: Puyang Baojie Wanjia Industry Co Ltd
Current assignee: Puyang Baojie Wanjia Industry Co Ltd
Priority date: 2015-04-14
Filing date: 2015-04-14
Publication date: 2015-09-16
Anticipated expiration: 2035-04-14
Also published as: CN104907292B

Abstract

The invention provides a high sour gas field gas gathering station sand flushing cleaning process. By means of the process, sand flushing cleaning is conducted on devices in a gas gathering station through a sand flushing skid-mounted part without production halt, fluid in an existing pipeline firstly flows into a downstream device through a bypass device, the devices to be cleaned are turned off and are then passivated, cleaned through cleaning agent, flushed through clean water and the like, finally the fluid is adjusted to flow in the existing devices, the sand flushing skid-mounted part is detached, and the cleaning work is completed. The cleaning process is easy, convenient and rapid to operate and free of hoisting, safety of devices and personnel is high during cleaning, agent and water used in the cleaning process can be circulated, and resources are saved.

Description

Sand washing and cleaning process for gas gathering station of high-sulfur-content gas field

Technical Field

The invention relates to a sand washing and cleaning process for a gas gathering station of a high-sulfur-content gas field, in particular to a process for independently washing sand of equipment or a container in the gas gathering station of the high-sulfur-content gas field under the condition of no production stop.

Background

Natural gas produced from natural gas fields (hereinafter simply referred to as "gas fields") often contains a large amount of sulfides. For such high sulfur acid-containing natural gas, after water-gas separation, scale mainly comprising sulfur is easily deposited in gas collection and transportation pipelines and equipment containers. Particularly, in the production process of the high-sulfur acid gas field, because the pressure is gradually reduced and the temperature is continuously reduced in the process that natural gas flows from the well bottom to the well head and then to the gathering and transportation system, elemental sulfur is separated out, and in addition, residual substances of fracturing fluid returned from the well bottom and the like are continuously attached to the inner wall of a pipeline, so that the production system is seriously blocked, the production stop and other serious consequences are caused, and the blockage problems bring serious influence on the safe and stable production and operation of the gathering and transportation system.

Through analysis, the fouling is generated because sulfur deposited on the inner walls of pipelines and equipment during long-term operation of the pipelines and the equipment interacts with carbonate, ferrous sulfide, mercaptan, corrosive impurities and the like, and sulfur fouling which is mutually connected is formed in the pipelines and the equipment. The scale substance takes polysulfide as a framework, and iron oxide, carbonate particles and corrosive impurities as fillers. The scale is hard, has strong smell, is slightly soluble in ethanol and ether, and is easily soluble in carbon disulfide; however, the chemical drugs belong to toxic and harmful substances, and the environmental hazard is serious, so that the function of a human body is damaged; the second is that due to some debris produced by the formation, these impurities are carried by the natural gas into the vessel and form deposits within the vessel.

In order to avoid production stop or other safety problems caused by blockage of a gathering and transportation system of the high-sulfur-acid-content natural gas field, blockage removal is needed.

Because the sediment can not be completely dissolved by the cleaning agent, and because of the limitation of the tank body structure, the sediment such as sludge deposited at the bottom can only be opened by a manhole blind plate finally, and a manual cleaning method is adopted.

However, the volumes of the metering separator, the torch liquid separation tank, the acid liquor buffer tank and other containers in the natural gas gathering station of the high-sulfur-content gas field are not very large, the internal space is limited, and a sufficient working surface is not provided, and in addition, the sludge contains unpleasant and harmful gases such as hydrogen sulfide, and the like, and a great potential safety hazard exists in a manual tank-entering decontamination mode.

In addition, the blockage removing and cleaning work of the natural gas gathering station of the high-sulfur-content gas field is to clean the whole system under the condition of production stoppage, so that the time is long, generally 2-3 months are needed, and millions of dollars of economic loss can be caused in the gas gathering station every day of production stoppage; and the dirt amount in each setting or device in the system is all great, is easy to block up the pipe in the cleaning process, and brings extra pollutants for the part with small dirt amount.

Therefore, for equipment or devices such as metering separators and torch liquid separation tanks which are easy to deposit dirt, a process scheme which can achieve quick cleaning and ensure the safety of the equipment and operators needs to be developed.

Disclosure of Invention

In order to solve the above problems, the present inventors have conducted intensive studies and, as a result, have found that: before cleaning equipment in a high-sulfur-content gas field gas gathering station, the equipment to be cleaned is cut off, fluid in the system is introduced into a bypass device, the fluid continuously flows in a pipeline through the bypass device, then the equipment to be cleaned is skid-mounted and communicated with sand washing cleaning, and the sand washing cleaning is carried out on the equipment to be cleaned through the steps of pretreatment, sulfur dissolving and passivation, finally, flushing with clear water and the like, so that the operation of cleaning the equipment without stopping production is finished, and in the cleaning process, workers do not need to enter the equipment to be cleaned to carry out manual operation.

The object of the present invention is to provide the following:

in a first aspect, the sand washing and cleaning process for the gas gathering station of the high-sulfur-content gas field is characterized by comprising the following steps of:

(1) opening an inlet valve and an outlet valve of the bypass device, closing the inlet valve and the outlet valve of the equipment to be cleaned, and adjusting the fluid in the original pipeline to flow into downstream equipment through the bypass device;

(2) communicating the sand washing skid with equipment to be cleaned;

(3) injecting a cleaning agent into the sand washing agent tank to soak and wash the interior of equipment to be cleaned;

(4) after the interior of the cleaning equipment is cleaned, emptying the cleaning agent, and injecting clear water into the sand washing agent tank to enable the clear water to flow through the equipment to be cleaned;

(5) emptying clear water, closing a sand washing port and a waste liquid port of equipment to be cleaned, opening a passage valve of the equipment, closing a valve of a bypass device, and removing the connection between a sand washing skid and the sand washing port and the waste liquid port of the equipment to be cleaned.

In a second aspect, the present invention also provides the above process, which is characterized in that after step 2 and before step 3, the process further comprises the following steps,

(2') injecting a first passivating agent into the sand washing agent tank, and enabling the first passivating agent to flow through the equipment to be cleaned.

In a third aspect, the present invention also provides the above process, wherein,

the sand washing skid-mounted device comprises a sand washing agent tank 1 arranged on a transport vehicle; the sand washing agent tank 1 is provided with a medicine inlet 11, a medicine outlet 12, a first backflow port 131 and a second backflow port 132.

In a fourth aspect, the invention also provides the process, which is characterized in that the sand washing skid-mounted device further comprises a sand washing water pump 3, a diaphragm pump 4, a filtering separator 5, a cyclone separator 6 and a circulating pump 7, wherein,

the sand washing water pump 3 is arranged between the medicine outlet 13 and a sand washing port 21 of the equipment to be cleaned; and/or

One end of the diaphragm pump 4 is communicated with a pipeline between the waste liquid port 22 of the equipment to be cleaned and the filtering separator 5; the other end is communicated with a pipeline between the filtering separator 5 and the circulating pump 7; and/or

The filtering separator 5 is arranged between the waste liquid port 22 of the equipment to be cleaned and the first backflow port 131 of the sand washing agent tank 1; and/or

The cyclone separator 6 is arranged between the filtering separator 5 and the first backflow port 131 of the sand washing medicament tank 1; and/or

The circulation pump 7 is arranged between the filter separator 5 and the cyclone separator 6.

In a fifth aspect, the invention further provides the above process, which is characterized in that the sand washing skid further comprises a reverse washing pipeline, the reverse washing pipeline comprises a reverse liquid inlet pipe 23 and a reverse liquid outlet pipe 24, wherein,

one end of the reverse liquid inlet pipe 23 is communicated with a pipeline between the sand washing water pump 3 and the sand washing port 21 of the equipment to be cleaned, the other end of the reverse liquid inlet pipe is communicated with a pipeline between the waste liquid port 22 of the equipment to be cleaned and the filtering separator 5, and a valve is arranged on the reverse liquid inlet pipe; and/or

One end of the reverse liquid outlet pipe 24 is communicated with a reagent backflushing reserved port 25 on the equipment to be cleaned, and the other end of the reverse liquid outlet pipe is communicated with a second backflow port 132 on the sand washing reagent tank.

In a sixth aspect, the present invention also provides the above process, wherein the sand washing agent tank 1 further comprises a breather valve 14, an electric heating device 15, a first liquid level meter 16, a second liquid level meter 17, a deslagging port 18, a sewage draining port 19 and/or an industrial observation mirror 110, wherein,

the breather valve 14 is arranged at the top of the sand washing medicament tank 1; and/or

The electric heating device 15 is arranged inside the sand washing agent tank 1; and/or

The first liquid level meter 16 is arranged inside the sand washing agent tank 1; and/or

The second liquid level meter 17 is arranged in the middle of the right side wall of the sand washing agent tank 1; and/or

The deslagging port 18 is arranged at the bottom of the right side of the sand washing agent tank 1; and/or

The sewage outlet 19 is arranged at the bottom of the left side of the sand washing agent tank 1; and/or

The industrial observation mirror 110 is arranged in the middle of the left side wall of the sand washing agent tank 1; and/or

The pH detector 111 is arranged in the middle of the left side wall of the sand washing agent tank 1, below the industrial observation mirror 110 and above the electric heating device 15; and/or

The outlet 12 of the sand washing agent tank is communicated with the sand washing port 21 of the equipment to be cleaned, so that the first return port 131 of the sand washing agent tank is communicated with the waste liquid port 22 of the equipment to be cleaned.

In a seventh aspect, the present invention also provides the above process, wherein in step 2', the first passivation agent is prepared from the following components in parts by weight,

in an eighth aspect, the invention further provides the above process, wherein in step 4, the cleaning agent comprises the following components in parts by weight,

5-10 parts of sulfur dissolving agent

3-15 parts of dispersant

1-18 parts of a complexing agent;

wherein,

the sulfur dissolving agent is selected from water-soluble metal hydroxide, amine compounds and compositions thereof in any proportion, preferably sodium hydroxide, ethylenediamine, diethylamine, methyldiethanamine, diethylenetriamine and compositions thereof in any proportion; more preferably sodium hydroxide, diethylamine and combinations thereof in any proportion;

the dispersant is a surfactant and/or a coupling agent, preferably a composition selected from one or more of a cationic surfactant, an anionic surfactant, a nonionic surfactant, a zwitterionic surfactant, a titanate coupling agent, a silane coupling agent, an aluminate coupling agent and a bimetallic coupling agent, more preferably sodium dodecyl sulfate, 1,2, 4-butanetriol, isopropyl tri (dioctyl pyrophosphoryl) titanate TMC-201, isopropyl tri (dioctyl phosphatoryl) titanate TMC-102, isopropyl dioleayloxy (dioctyl phosphatyloxy) titanate TMC-101, monoalkoxy unsaturated fatty acid titanate TMC-105, pyrophosphoric monoalkoxy titanate TMC-114 and a composition thereof in any proportion, and further preferably sodium dodecyl sulfate, silane coupling agent, aluminate coupling agent and bimetallic coupling agent, 1,2, 4-butanetriol, pyrophosphoric acid type monoalkoxyl titanate TMC-114 and a composition thereof in any proportion;

the complexing agent is selected from aminotrimethylene phosphonic acid, polyaspartic acid, sodium hexametaphosphate, ethylene diamine tetraacetic acid and salts thereof, nitrilotriacetic acid (NTA), sodium nitrilotriacetate, di (2-ethylhexyl) phosphate and compositions thereof in any proportion, and the like, preferably the ethylene diamine tetraacetic acid, the sodium ethylene diamine tetracetate, the nitrilotriacetic acid (NTA), the polymerization degree of 300-500, and preferably the polyaspartic acid of 350-400, the di (2-ethylhexyl) phosphate and compositions thereof in any proportion.

In a ninth aspect, the invention also provides the process, which is characterized in that the medicine outlet 12 of the sand washing agent tank 1 is connected with the sand washing port 21 of the equipment to be cleaned through a high-pressure rubber pipe, and one end of the high-pressure rubber pipe, which is communicated with the equipment to be cleaned, is provided with a high-pressure rubber pipe matching quick connector.

In a tenth aspect, the present invention also provides the above process, wherein,

in step 1, before opening an inlet valve and an outlet valve of a bypass device, setting parameters of the bypass device to be the same as parameters of equipment to be cleaned in operation; and/or

In step 2, when the equipment is cleaned, the required chemical is added into the sand washing chemical tank 1 through the chemical inlet 11, the chemical in the sand washing chemical tank 1 is injected into the equipment to be cleaned through the sand washing port 21 of the equipment to be cleaned, the chemical flows out through the waste liquid port 22 of the equipment to be cleaned after the interior of the equipment to be cleaned is cleaned, and the chemical is regenerated and then injected into the sand washing chemical tank 1 through the first return port 131 for recycling; and/or

When the equipment to be cleaned is subjected to the back flushing operation, the medicament in the equipment to be cleaned flows out from the medicament back flushing reserved opening 25 and is directly injected into the sand flushing medicament tank 1 through the second backflow opening 132 without being processed for recycling; and/or

In the sand washing agent tank, the agent in the sand washing agent tank 1 is heated by an electric heating device 15, preferably to 70-80 ℃; and/or

In the step 2', the first passivating agent flows and washes in the equipment to be cleaned for 0.2-2 hours; and/or

In the step 3, monitoring the pH value of the cleaning agent in the sand washing agent tank 1 to keep the pH value of the cleaning agent at 9-13, preferably 10-12; and/or

Monitoring the liquid level height of a cleaning agent in the sand washing agent tank 1, and supplementing the cleaning agent into the sand washing agent tank 1 when the cleaning agent is lower than the preset liquid level height; when the cleaning agent is higher than the preset liquid level height, opening a drain outlet 19 of the sand washing agent tank 1 to enable the liquid level height of the cleaning agent to be within the range of the preset liquid level height; and/or

Monitoring the pressure of a cleaning agent entering the sand washing port 21 of the equipment to be cleaned, simultaneously monitoring the pressure of waste liquid flowing out of the waste liquid port 22 of the equipment to be cleaned, and stopping cleaning the equipment to be cleaned when the pressure of the waste liquid is close to or equal to the pressure at the sand washing port 21; and/or

In step 4, after the interior of the equipment to be cleaned is cleaned and the inner wall of the equipment to be cleaned is fully passivated, a drain outlet 19 of the sand washing agent tank 1 is opened to discharge the cleaning agent, and meanwhile, the diaphragm pump 4 is optionally opened to discharge the residual cleaning agent in the equipment to be cleaned out of the equipment to be cleaned as much as possible; and/or

Monitoring the pH value of the backflow water at the first backflow port 131 of the sand washing agent tank 1, and stopping injecting clear water into the equipment to be cleaned when the pH value of the backflow water reaches 7-9; and/or

And (3) intensively recovering the solid impurities separated by the filtering separator 5 and the cyclone separator 6 in any step of the step (1) to the step (5), and preferably, pressing and filtering the solid impurities into blocks for recycling.

Drawings

FIG. 1 shows a flow chart of a preferred sand washing cleaning process for a high sulfur content gas field gathering station according to the present invention;

FIG. 2 is a schematic diagram of a preferred sand washing agent canister according to the present invention;

FIG. 3 shows a photograph of the interior of a flare liquid separating tank in a Sichuan common light gas gathering station before cleaning;

FIG. 4 shows a photograph of the inside of a torch liquid separation tank in a Sichuan common light gas gathering station after cleaning;

FIG. 5 is a photograph showing the inside of a metering separator in a Sichuan common light gathering station before cleaning;

fig. 6 shows a photograph of the inside of the metering separator in the sichuan universal light header after cleaning.

The reference numbers illustrate:

1-sand washing medicament tank

11-medicine inlet

110-Industrial observation mirror

111-pH detector

12-medicine outlet

131-first return port

132-second Return Port

14-breather valve

15-electric heating device

16-first level gauge

17-second level gauge

18-slag removal port

19-sewage draining outlet

21-sand washing port

22-waste liquid port

3-sand washing water pump

4-diaphragm pump

5-filtration separator

6-cyclone separator

7-circulation pump

Detailed Description

The features and advantages of the present invention will become more apparent and appreciated from the following detailed description of the invention.

The word "exemplary" is used exclusively herein to mean "serving as an example, embodiment, or illustration. Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. While the various aspects of the embodiments are presented in drawings, the drawings are not necessarily drawn to scale unless specifically indicated.

The present invention is described in detail below.

According to a first aspect of the invention, a sand washing and cleaning process for a gas gathering station of a high-sulfur-content gas field is provided, which comprises the following steps:

step 1, opening an inlet valve and an outlet valve of a bypass device, closing the inlet valve and the outlet valve of equipment to be cleaned, and adjusting fluid in an original pipeline to flow into downstream equipment through the bypass device.

In the invention, before the equipment to be cleaned is closed, a bypass device is arranged outside the equipment to be cleaned, the bypass device is communicated with the upstream equipment and the downstream equipment of the equipment to be cleaned, when the bypass device is opened and the equipment to be cleaned is closed, fluid in an original pipeline can flow into the downstream equipment of the equipment to be cleaned from the upstream equipment of the equipment to be cleaned through the bypass device, namely, the fluid in the original pipeline can normally flow in the pipeline, so that the production continuity is ensured, and preferably, the bypass device and the equipment to be cleaned have the same function.

Before the equipment to be cleaned is closed, the inlet and outlet valves of the bypass device are opened, so that the fluid in the original pipeline flows into the bypass device, and then the inlet and outlet valves of the equipment to be cleaned are closed, thereby ensuring that the fluid in the original pipeline keeps flowing when the valves are switched, and further ensuring the uninterrupted production.

More preferably, the parameters of the bypass device are set to be the same as those when the apparatus to be cleaned is operating, before opening the inlet and outlet valves of the bypass device.

In the invention, for the pipeline designed with the bypass device, the valve can be directly adjusted to enable the fluid to pass through the bypass device; for pipelines without bypass devices, the bypass devices are first connected to the pipeline by three-way valves and/or other valves at both ends of the equipment to be cleaned.

And 2, communicating the sand washing skid with equipment to be cleaned.

In the invention, the sand washing skid-mounted device comprises a sand washing agent tank 1 arranged on a transport vehicle, wherein the sand washing agent tank 1 is provided with a medicine inlet 11, a medicine outlet 12, a first backflow port 131 and a second backflow port 132, and a required agent is added into the sand washing agent tank 1 from the medicine inlet 11 when equipment is cleaned; when the equipment is cleaned, the medicine outlet 12 is communicated with a sand washing port 21 of the equipment to be cleaned, so that the medicine in the sand washing medicine tank 1 is injected into the equipment to be cleaned from the sand washing port 21 of the equipment to be cleaned; the first backflow port 131 of the sand washing agent tank 1 is communicated with the waste liquid port 22 of the equipment to be cleaned, and after the inside of the equipment to be cleaned is treated, the agent flows out of the waste liquid port 22 of the equipment to be cleaned, is subjected to regeneration treatment, and is injected into the sand washing agent tank 1 again through the first backflow port 131 for recycling; the second backflow port 132 is communicated with the reagent backflushing reserved port 25 of the equipment to be cleaned, and when the equipment to be cleaned is subjected to backflushing operation, the reagent in the equipment to be cleaned flows out of the reagent backflushing reserved port 25 and is directly injected into the sand washing reagent tank 1 through the second backflow port 132 without being processed for recycling.

In a preferred embodiment of the present invention, as shown in fig. 1, the medicine inlet 11 is disposed on the top of the left sidewall of the sand washing medicine tank 1, the first backflow port 131 is disposed on the top of the right sidewall of the sand washing medicine tank 1, and the second backflow port 132 is disposed below the medicine inlet 11.

In a more preferred embodiment of the present invention, as shown in fig. 2, a breather valve 14 is further opened at the top of the sand washing chemical tank 1, and is capable of adjusting the pressure in the sand washing chemical tank 1 according to the amount of the drug in the sand washing chemical tank 1, so that the pressure in the sand washing chemical tank 1 and the atmospheric pressure difference are kept within a safe pressure difference range.

In a more preferred embodiment of the present invention, as shown in fig. 1, an electric heating device 15 is further disposed inside the sand washing agent tank 1, and when the temperature of the construction environment is low, the electric heating device 15 can heat the agent in the sand washing agent tank 1, in the present invention, the first passivating agent is suitably used at a temperature of 70 ℃ to 80 ℃, the cleaning agent is suitably used at a temperature of 70 ℃ to 80 ℃, and the clear water is suitably used at a temperature of 70 ℃ to 80 ℃, so that the agent can be used at a suitable temperature, and the flushing efficiency is high.

The inventor finds that when the temperature of the cleaning agent is higher than 70 ℃, the chemical dissolution effect of the sulfur dissolving agent and the scale substances in the cleaning agent is good, the passivation reaction between the passivating agent and the inner wall of the equipment to be cleaned is sufficient, the safety requirement of the gas field gas gathering station requires that the temperature of fluid in each equipment is lower than 80 ℃, and therefore, the temperature of the cleaning agent is selected to be 70-80 ℃.

The inventor also finds that when the temperature of the clean water is higher than 70 ℃, the clean water can be quickly and thoroughly washed clean by the cleaning agent remained on the inner wall of the equipment to be cleaned, the passivation layer is still attached to the inner wall of the equipment to be cleaned, and the temperature of the fluid in each equipment is required to be lower than 80 ℃ according to the safety requirement of the gas field gas gathering station, so that the temperature of the cleaning agent is selected to be 70-80 ℃.

In a more preferred embodiment of the present invention, as shown in fig. 1, a first liquid level meter 16 is further disposed inside the sand-washing chemical tank 1, and the first liquid level meter 16 indicates the liquid level of the liquid medicine in the sand-washing chemical tank 1, so as to control the liquid level of the liquid medicine above the electric heating device 15 and below the chemical inlet 11.

More preferably, as shown in fig. 1, a second liquid level meter 17 is further disposed in the middle of the right side wall of the sand washing chemical tank 1, and the second liquid level meter 17 is preferably a magnetic flap type liquid level meter and is used in cooperation with the first liquid level meter 16, so that when chemicals with different densities are added into the chemical tank, the liquid level height in the sand washing chemical tank 1 can be accurately displayed, and the safety of the sand washing chemical tank 1 during use is ensured.

In a more preferred embodiment of the present invention, as shown in fig. 1, a slag removal hole 18 is further opened in the bottom of the right side of the sand washing chemical tank 1, and solid impurities carried in the chemical recovered and reused by the first and second return ports 131 and 132 can be discharged out of the sand washing chemical tank 1 through the slag removal hole 18.

In a more preferred embodiment of the present invention, as shown in fig. 1, a plurality of sewage outlets 19 are further formed in the bottom of the left side of the sand washing agent tank 1, and when the agents in the sand washing agent tank 1 are replaced, the sewage outlets 19 can be opened first to discharge the waste agents, and the waste agents are contained in a designated container, and then the sewage outlets 19 are closed to charge new agents.

In a more preferred embodiment of the present invention, as shown in fig. 1, an industrial observation mirror 110 is further disposed in the middle of the left side wall of the sand washing agent tank 1, the industrial observation mirror 110 is disposed below the second backflow port 132 and above the electric heating device 15, and the condition of the agent inside the sand washing agent tank 1 can be observed through the industrial observation mirror 110, on the one hand, when the first liquid level gauge 16 and the second liquid level gauge 17 fail, the liquid level inside the sand washing agent tank can be observed through the industrial observation mirror 110; on the other hand, the color of the chemical liquid can be observed through the industrial observation mirror 110, thereby judging the cleaning degree of the equipment to be cleaned.

In a more preferred embodiment of the present invention, as shown in fig. 1, a pH detector 111 is further disposed in the middle of the left sidewall of the sand washing agent tank 1, below the industrial observation mirror 110, and above the electric heating device 15, for monitoring the pH of the agent in the sand washing agent tank 1, so as to maintain the agent in a pharmaceutically effective pH range. For example, the effective pH range of the first passivating agent is 7-10, preferably 8-9; the effective pH range of the cleaning agent is 9-13; the pH range of the clear water is 7-8.

In a more preferred embodiment of the present invention, as shown in fig. 1, the sand washing skid further comprises a sand washing water pump 3, and the sand washing water pump 3 is disposed between the chemical outlet 13 and a sand washing port 21 of the equipment to be cleaned, and is used for providing power for the chemical agent flowing to the equipment to be cleaned, so that the chemical agent can flow into the equipment to be cleaned.

In a more preferred embodiment of the present invention, as shown in fig. 1, a reverse flushing pipeline is further disposed in the sand washing skid, and the reverse flushing pipeline includes a reverse liquid inlet pipe 23 and a reverse liquid outlet pipe 24, wherein one end of the reverse liquid inlet pipe 23 is communicated with a pipeline between the sand washing water pump 3 and the sand washing port 21 of the device to be cleaned, and the other end is communicated with a pipeline between the waste liquid port 22 of the device to be cleaned and the filtering separator 5, and a valve is disposed thereon; one end of the reverse liquid outlet pipe 24 is communicated with a reagent backflushing reserved port 25 on the equipment to be cleaned, and the other end of the reverse liquid outlet pipe is communicated with a second backflow port 132 on the sand washing reagent tank.

When the waste liquid port 22 of the equipment to be cleaned is blocked or the cleaning is nearly finished, the valves on the reverse liquid inlet pipe 23 and the reverse liquid outlet pipe 24 are opened, the valve between the sand washing water pump 3 and the sand washing port 21 is closed, the inlet valve of the downstream equipment is closed, so that the liquid medicine is injected into the equipment to be cleaned from the waste liquid port 22 of the equipment to be cleaned, and flows out of the equipment to be cleaned from the reagent backflushing reserved port 25, and the reverse flushing of the equipment to be cleaned is realized.

In a more preferred embodiment of the present invention, as shown in fig. 1, the sand washing skid further comprises a filter separator 5, the filter separator 5 is disposed between the waste liquid port 22 of the equipment to be cleaned and the first backflow port 131 of the sand washing agent tank 1, the filter separator 5 is capable of filtering the waste liquid flowing out from the waste liquid port 22 of the equipment to be cleaned, and filtering solid impurities with larger particle size, such as solid impurities with particle size larger than 3mm, contained therein; more preferably, an inlet valve and an outlet valve are provided on the left and right sides of the filtering separator 5, respectively, and when the inlet valve and the outlet valve are opened, the fluid passes through the filtering separator 5 to be subjected to the filtering separation process, and when the inlet valve and the outlet valve are closed, the fluid does not pass through the filtering separator 5, that is, the filtering separation process is not performed.

In a further preferred embodiment of the present invention, a bypass pipeline 51 is disposed on one side of the filtering separator 5, one end of the bypass pipeline 51 is communicated with a left pipeline of the filtering separator 5, and the other end is communicated with a right pipeline of the filtering separator 5, more preferably, a valve is disposed on the bypass pipeline 51, when the cleaning of the device to be cleaned approaches the end sound, the content of solid impurities contained in the waste liquid is significantly reduced, at this time, the valve on the bypass pipeline 51 is opened, and the waste liquid directly enters downstream equipment through the bypass pipeline 51 without passing through the filtering separator 5, so as to accelerate the backflow speed of the waste liquid; when the waste liquid contains more solid impurities, the valve on the bypass pipeline 51 is closed, and the waste liquid is forced to pass through the filter separator 5 for solid-liquid separation.

In a more preferred embodiment of the present invention, as shown in fig. 1, the sand washing skid further comprises a diaphragm pump 4, the diaphragm pump 4 is disposed at one side of the filtering separator 5, the pipeline at the left side thereof is communicated with the pipeline at the left side of the filtering separator 5, the pipeline at the right side thereof is communicated with the pipeline at the right side of the filtering separator 5, and more preferably, an inlet valve and an outlet valve are disposed at both sides of the diaphragm pump 4, respectively, and when the inlet valve and the outlet valve are opened, the fluid flows from the diaphragm pump 4 to the downstream equipment; when the inlet and outlet valves are closed, the fluid does not pass through the membrane pump 4.

In the present invention, the waste liquid port 22 of the device to be cleaned is lower than the filtering separator 5 and the bypass pipeline 51 thereof, so that when the medicament or clean water in the device to be cleaned is emptied, residual liquid always remains in the device to be cleaned.

In a more preferred embodiment of the present invention, as shown in fig. 1, the sand washing skid further includes a cyclone separator 6, the cyclone separator 6 is disposed between the filter separator 5 and the first return port 131 of the sand washing agent tank 1, the cyclone separator 6 is capable of further performing solid-liquid separation on the waste liquid subjected to the preliminary solid-liquid separation by the filter separator 5 or the waste liquid which has a lower content of solid impurities and is not separated by the filter separator 5, and removing solid impurities with a smaller particle size, such as solid impurities with a particle size of less than 3mm, contained in the waste liquid, so as to obtain a recovered agent, so that the recovered agent returned to the sand washing agent tank 1 carries the solid impurities as little as possible.

More preferably, the flow rate of the cyclone separator is 1-7 m³Preferably 3 to 5m³/h。

In a more preferred embodiment of the present invention, as shown in fig. 1, the sand washing skid further comprises a circulation pump 7, the circulation pump 7 is disposed between the filter separator 5 and the cyclone separator 6, and the circulation pump can provide sufficient power for the waste liquid flowing into the cyclone separator 6, so that the waste liquid forms a vortex in the cyclone separator 6, thereby realizing solid-liquid separation and further separating solid impurities in the waste liquid.

In a more preferred embodiment of the invention, the medicine outlet 12 of the sand washing agent tank 1 is connected with the sand washing port 21 of the equipment to be cleaned through a high-pressure rubber pipe, and one end of the high-pressure rubber pipe, which is communicated with the equipment to be cleaned, is provided with a high-pressure rubber pipe adapting quick joint.

In a preferred embodiment of the present invention, as shown in fig. 3, the high-pressure hose-adapting quick connector is any commercially available adapting quick connector, which is manufactured by zeelanchier-free majestic stainless products ltd and has a model number of 3 "-6" R.

In a preferred embodiment of the present invention, step 2' is optionally included after step 2.

And 2', injecting a first passivating agent into the sand washing agent tank 1, and enabling the first passivating agent to flow through equipment to be cleaned.

The first passivator comprises the following components in parts by weight,

preferably, the first and second liquid crystal materials are,

more preferably, the first and second liquid crystal materials are,

the first passivating agent can passivate dangerous substances which are easy to generate oxidation reaction and cause spontaneous combustion or explosion, such as ferrous sulfide solids and/or hydrogen sulfide gas in equipment to be cleaned, so that the substances have stable chemical properties under the aerobic and normal-temperature conditions, and the operation safety during cleaning the equipment to be cleaned is ensured.

The first passivating agent is weakly alkaline under the combined action of sodium hypochlorite, nitrosamine, hydrazine, trisodium phosphate and sodium hexametaphosphate, and a large amount of acidic dirt such as hydrogen sulfide and ferrous sulfide is remained in equipment to be cleaned, so that the equipment to be cleaned is passivated by the first passivating agent and can be subjected to neutralization reaction with the acidic dirt, and strong oxidizing agents such as potassium permanganate, sodium chlorite and sodium nitrite can oxidize reductive substances such as ferrous sulfide in the dirt into a stable state, so that the safety of subsequent equipment to be cleaned is improved.

In a preferred embodiment of the invention, the first passivating agent is injected into the sand washing agent tank 1 through the agent inlet 11, the agent outlet 12 is opened, so that the first passivating agent is introduced into the equipment to be cleaned under the action of the sand washing water pump 3 and flows in the forward direction in the equipment to be cleaned, namely, the first passivating agent enters the equipment to be cleaned through the sand washing port 21 of the equipment to be cleaned and is discharged out of the equipment to be cleaned through the sewage outlet 22 of the equipment to be cleaned, the first passivating agent continuously reacts with ferrous sulfide and/or hydrogen sulfide and other substances in the equipment to be cleaned in the process of continuously washing the equipment to be cleaned, and the remaining first passivating agent can flow back into the sand washing agent tank 1 for recycling.

When the equipment to be cleaned is passivated for the first time, the valves of the filtering separator 5 and the cyclone separator 6 are opened, so that the waste liquid flowing out from the waste liquid port 22 of the equipment to be cleaned is separated and then recycled to the sand washing medicament tank 1.

In a preferred embodiment of the invention, the pH detector 111 is used for monitoring the pH value of the first passivating agent in the sand washing agent tank 1, so that the pH value of the first passivating agent is kept between 7 and 10, preferably between 8 and 9, thereby ensuring the passivating effect of the first passivating agent.

More preferably, the liquid level of the first passivating agent in the sand washing agent tank 1 is monitored, and when the first passivating agent is lower than the preset liquid level, the first passivating agent is supplemented into the sand washing agent tank 1; when the first passivating agent is higher than the preset liquid level height, the sewage discharge port 19 of the sand washing agent tank 1 is opened, so that the liquid level height of the first passivating agent is within the preset liquid level height range.

More preferably, the first passivating agent is flushed in the equipment to be cleaned for 0.2 to 2 hours, preferably 0.5 to 1.5 hours, such as 1 hour.

And 3, after the dirt in the cleaning equipment is passivated, emptying the first passivating agent, and then injecting a cleaning agent into the sand washing agent tank 1 to soak and wash the interior of the cleaning equipment.

The cleaning agent comprises the following components in parts by weight,

5-10 parts of sulfur dissolving agent

3-15 parts of dispersant

1-18 parts of a complexing agent;

wherein,

the sulfur dissolving agent is selected from water-soluble metal hydroxide, amine compounds and compositions thereof in any proportion, preferably sodium hydroxide, ethylenediamine, diethylamine, methyldiethanamine, diethylenetriamine and compositions thereof in any proportion; more preferably sodium hydroxide, diethylamine and combinations thereof in any proportion.

The dispersing agent is a surfactant and/or a coupling agent, and can attach effective components in the cleaning agent to the surface of dirt and the inner wall of equipment to be cleaned, so that the cleaning agent and the dirt are fully reacted, and the cleaning is more full and thorough.

The dispersant is preferably selected from the group consisting of a combination of one or more of a cationic surfactant, an anionic surfactant, a nonionic surfactant, a zwitterionic surfactant, a titanate coupling agent, a silane coupling agent, an aluminate coupling agent and a bimetallic coupling agent, more preferably sodium lauryl sulfate, 1,2, 4-butanetriol, isopropyl tris (dioctyl pyrophosphato acyloxy) titanate TMC-201, isopropyl tris (dioctyl phosphato) titanate TMC-102, isopropyl dioleoyloxy (dioctyl phosphato) titanate TMC-101, monoalkoxy unsaturated fatty acid titanate TMC-105, pyrophosphate type monoalkoxy titanate TMC-114 and a composition thereof in any proportion, and further preferably sodium lauryl sulfate, 1,2, 4-butanetriol, pyrophosphate type monoalkoxy titanate TMC-114 and a composition thereof in any proportion.

The complexing agent is selected from aminotrimethylene phosphonic acid, polyaspartic acid, sodium hexametaphosphate, ethylene diamine tetraacetic acid and salts thereof, nitrilotriacetic acid (NTA), sodium nitrilotriacetate, di (2-ethylhexyl) phosphate and compositions thereof in any proportion, preferably the ethylene diamine tetraacetic acid, the sodium ethylene diamine tetracetate, the nitrilotriacetic acid (NTA), the polyaspartic acid with the polymerization degree of 300-500, preferably 350-400, the di (2-ethylhexyl) phosphate and compositions thereof in any proportion,

the polymerization degree is 300-500, preferably 350-400, and the polyaspartic acid has a good corrosion inhibition effect when the pH value is about 10, so that the corrosion speed of the inner wall of equipment to be cleaned by dirt can be delayed.

The ethylene diamine tetraacetic acid and the sodium ethylene diamine tetracetate can eliminate the inhibition effect in the enzyme catalytic reaction caused by trace heavy metals.

The nitrilotriacetic acid and the sodium salt thereof have very strong complexing ability, can form a complex with various metal ions, and enables the metal ions contained in the dirt to form a complex which is stable and easy to clean, so that the equipment to be cleaned is cleaned, and the environmental pollution is avoided.

In use, the concentration of the aqueous cleaning agent solution is preferably 0.1-10%, preferably 0.5-5%, based on the concentration of the complexing agent.

In a preferred embodiment of the invention, the cleaning agent comprises the following components in parts by weight:

preferably, the first and second liquid crystal materials are,

and when the ferrous sulfide and/or hydrogen sulfide and the like in the equipment to be cleaned are/is fully passivated, closing the medicine outlet 12 of the sand washing agent tank 1, and exhausting the equipment to be cleaned and the first passivator in the sand washing agent tank 1.

In a preferred embodiment of the present invention, after the dirt in the equipment to be cleaned is sufficiently passivated by the first passivating agent, the drain outlet 19 of the sand washing agent tank 1 is opened to discharge the first passivating agent therein, and at the same time, the diaphragm pump 4 can be opened to discharge as much of the first passivating agent remaining in the equipment to be cleaned out of the equipment to be cleaned as possible.

In a more preferred embodiment of the present invention, after the first passivating agent in the sand washing agent tank 1 is emptied, the deslagging opening 18 on the sand washing agent tank 1 is opened, the solid impurities in the sand washing agent tank 1 are cleaned, and after the solid impurities are cleaned, the deslagging opening 18 is closed.

And after the first passivating agent in the sand washing agent tank 1 is completely removed, the chemical outlet 12 is closed, a cleaning agent is injected into the sand washing agent tank 1, and when the cleaning agent is injected to a preset height, the chemical outlet 12 is opened, so that the cleaning agent is injected into the equipment to be cleaned.

In a preferred embodiment of the invention, when the cleaning agent is injected into the equipment to be cleaned, the sand washing water pump 3 is opened at the same time, so that power is added to the cleaning agent, on one hand, the speed of the cleaning agent flowing into the equipment to be cleaned can be increased, on the other hand, the cleaning agent has larger power potential energy when entering the equipment to be cleaned, therefore, the cleaning agent has chemical dissolving effect and physical scouring effect on dirt in the equipment to be cleaned, and under the condition that the two effects exist at the same time, the dirt can be more quickly eluted from the inner wall of the container to be cleaned.

In a more preferred embodiment of the present invention, when the interior of the equipment to be cleaned is cleaned by using the cleaning agent to dissolve sulfur, insoluble silt existing in the equipment to be cleaned is carried out of the equipment to be cleaned along with the cleaning agent under the physical scouring action of the cleaning agent, but a large amount of silt may block the waste liquid port 22 of the equipment to be cleaned, at this time, the valve on the back flushing pipeline is adjusted to inject the cleaning agent into the equipment to be cleaned from the waste liquid port 22 of the equipment to be cleaned, that is, the equipment to be cleaned is back flushed, so as to remove solid dirt such as silt blocking the waste liquid port 22, and then the valve on the back flushing pipeline is adjusted to inject the cleaning agent into the equipment to be cleaned from the sand flushing port 21 of the equipment to be cleaned, thereby ensuring the continuity of cleaning agent for cleaning the interior of the equipment to be cleaned.

When the equipment to be cleaned is cleaned, the valves of the filtering separator 5 and/or the cyclone separator 6 are opened, so that the waste liquid flowing out from the waste liquid port 22 of the equipment to be cleaned is separated and then recycled to the sand washing agent tank 1.

In a preferred embodiment of the invention, the pH value of the cleaning agent in the sand washing agent tank 1 is monitored by a pH detector 111, so that the pH value of the cleaning agent is kept between 9 and 13, preferably between 10 and 12, and the sulfur dissolving and passivating effects of the cleaning agent are ensured.

More preferably, the liquid level height of the cleaning agent in the sand washing agent tank 1 is monitored, and when the cleaning agent is lower than the preset liquid level height, the cleaning agent is supplemented into the sand washing agent tank 1; when the cleaning agent is higher than the preset liquid level height, the sewage discharge port 19 of the sand washing agent tank 1 is opened, so that the liquid level height of the cleaning agent is in the range of the preset liquid level height.

In a more preferred embodiment of the invention, the pressure of the cleaning agent entering the sand washing port 21 of the equipment to be cleaned is monitored, and the pressure of the waste liquid flowing out of the waste liquid port 22 of the equipment to be cleaned is monitored, and when the pressure of the waste liquid is close to or equal to the pressure at the sand washing port 21, the cleaning of the equipment to be cleaned is stopped.

And 4, after the interior of the cleaning equipment is cleaned, emptying the cleaning agent, and injecting clean water into the sand washing agent tank 1 to enable the clean water to flow through the equipment to be cleaned.

After the interior of the equipment to be cleaned is cleaned, the medicine outlet 12 of the sand washing agent tank 1 is closed, and the equipment to be cleaned and the cleaning agent in the sand washing agent tank 1 are emptied.

In a preferred embodiment of the present invention, after the interior of the equipment to be cleaned is cleaned and the inner wall of the equipment to be cleaned is sufficiently passivated, the drain outlet 19 of the sand washing agent tank 1 is opened to discharge the cleaning agent therein, and at the same time, the diaphragm pump 4 can be opened to discharge the cleaning agent remaining in the equipment to be cleaned out of the equipment to be cleaned as much as possible.

In a more preferred embodiment of the present invention, after the cleaning agent in the sand washing agent tank 1 is emptied, the deslagging opening 18 on the sand washing agent tank 1 is opened to clean the solid impurities in the sand washing agent tank 1, and after the solid impurities are cleaned, the deslagging opening 18 is closed.

After the cleaning agent in the sand washing agent tank 1 is completely removed, the chemical outlet 12 is closed, clean water is injected into the sand washing agent tank 1, and when the clean water is injected to a preset height, the chemical outlet 12 is opened, so that the clean water is injected into the equipment to be cleaned.

In a preferred embodiment of the invention, when clean water is injected into the equipment to be cleaned, the sand washing water pump 3 is opened at the same time to increase power for the clean water, so that on one hand, the speed of injecting the clean water into the equipment to be cleaned can be increased, and on the other hand, the clean water has larger power potential energy when entering the equipment to be cleaned, so that the clean water has a physical scouring effect on the inner wall of the equipment to be cleaned, the residual cleaning agent amount on the inner wall of the equipment to be cleaned is rapidly reduced, and the cleaning efficiency is improved.

When the equipment to be cleaned is cleaned by clean water, the valve of the filtering separator 5 and/or the valve of the cyclone separator 6 are/is opened, so that the waste liquid flowing out from the waste liquid port 22 of the equipment to be cleaned is separated and then recycled to the sand washing medicament tank 1.

In a preferred embodiment of the invention, the pH value of the backflow water at the first backflow port 131 of the sand washing agent tank 1 is monitored, and when the pH value of the backflow water reaches 7-9, the injection of clean water into the equipment to be cleaned is stopped.

And 5, emptying clear water, closing the sand washing port 21, the waste liquid port 22 and the medicament backflushing reserved port 25 of the equipment to be cleaned, opening a passage valve of the equipment, closing a valve of a bypass device, and removing the connection between the sand washing skid-mounted device and the sand washing port 21 and the sewage outlet 22 of the equipment to be cleaned.

In a more preferred embodiment of the present invention, after the clean water in the sand washing agent tank 1 is emptied, the deslagging opening 18 on the sand washing agent tank 1 is opened to clean the solid impurities in the sand washing agent tank 1, and after the solid impurities are cleaned, the deslagging opening 18 is closed.

At the moment, the sand washing port 21 and the waste liquid port 22 of the equipment to be cleaned are closed, the channel valve of the equipment to be cleaned is opened, fluid in the original pipeline passes through the cleaned equipment to be cleaned and flows into the next equipment, then the valve of the bypass device is closed, the fluid in the original pipeline completely passes through the cleaned equipment to be cleaned and is recovered to be in a pipeline state before cleaning, then the connection between the sand washing skid and the two ends of the equipment to be cleaned is removed, and the cleaning work of the equipment to be cleaned is completed.

In another preferred embodiment of the invention, the sand wash port 21 of the equipment to be cleaned is lower than the waste port 22.

In a preferred embodiment of the present invention, the solid impurities separated by the filtering separator 5 and the cyclone separator 6 in any one of the steps 1 to 5 are collected collectively, and more preferably, the solid impurities are press-filtered into a cake and recovered.

The sand washing and cleaning process for the gas gathering station of the high-sulfur-content gas field provided by the invention has the following beneficial effects:

(1) the device for cleaning the torch liquid-separating tank, the metering separator, the acid liquor buffer tank and the like on line is cleaned under the condition that the gas gathering station does not stop production, so that the gas production rate of the gas gathering station is not influenced, and meanwhile, the economic loss of the gas gathering station is avoided;

(2) restoring the performance index of the equipment to be cleaned to normal;

(3) before cleaning, optionally using a first passivating agent to treat dirt in equipment to be cleaned, inhibiting generation and diffusion of toxic and harmful gases such as hydrogen sulfide and the like, and simultaneously inhibiting oxidation or spontaneous combustion of substances which are easy to oxidize and spontaneously combust such as ferrous sulfide and the like; further avoiding the harm of toxic gas and dangerous chemical substances to human bodies and environmental pollution in the construction process;

(4) the sewage generated in the cleaning process is subjected to mud-water separation and mud cake filter pressing, wherein the treated sewage can be recycled, so that the sewage quantity is reduced, and the purposes of environmental protection and energy conservation are achieved;

(5) the sand washing skid-mounted machine is an integrated vehicle-mounted movable sand washing skid-mounted machine, so that hoisting is not needed, potential safety hazards caused by hoisting are avoided, and hoisting cost is avoided;

(6) the sand washing skid-mounted device adopts a high-pressure rubber pipe to be connected with a quick connector, so that the connection time is reduced.

Examples of the experiments

Experimental example 1 by adopting the process provided by the invention, the liquid of the medium torch of the common light gas gathering station in Sichuan is separated Tank cleaning

The operation steps are as follows:

(1) opening an inlet and outlet valve of the bypass device, closing an inlet and outlet valve of the torch liquid separation tank, and adjusting natural gas in the original pipeline to flow into downstream equipment through the bypass device;

(2) the sand washing skid is communicated with a torch liquid separating tank;

(2') injecting a first passivating agent into the sand washing agent tank, starting an electric heating device, heating the first passivating agent to 70 ℃, enabling the heated first passivating agent to flow through a torch liquid separating tank, circularly flowing and washing for 30min, starting a diaphragm pump, and emptying the first passivating agent;

(3) injecting a cleaning agent into the sand washing agent tank, opening the electric heating device, heating the cleaning agent to 70 ℃, soaking and washing the inside of the torch liquid separating tank by the cleaning agent, monitoring the pressure difference between a sand washing port and a waste liquid port of the torch liquid separating tank, adjusting the valve to open the reverse washing pipeline when the pressure difference is continuously increased, adjusting the valve to close the reverse washing pipeline when the pressure difference is stabilized at a constant value, continuously washing in the forward direction for a plurality of times, and stopping washing until the pressure difference is close to 0;

(4) after the interior of the cleaning equipment is cleaned, opening the diaphragm pump, evacuating the cleaning agent in the torch liquid separation tank, injecting clean water into the sand washing agent tank, opening the electric heating device, heating the clean water to 70 ℃, enabling the clean water to flow through the torch liquid separation tank, monitoring the pH value of the clean water flowing back from the backflow port of the sand washing agent tank, and stopping the clean water washing when the pH value is 8;

(5) opening the diaphragm pump, emptying clear water, closing the sand washing port and the waste liquid port of the torch liquid separating tank, opening the passage valve of the torch liquid separating tank, closing the valve of the bypass device, and dismantling the connection between the sand washing skid-mounted device and the sand washing port and the waste liquid port of the torch liquid separating tank.

Wherein the first passivator consists of the following components in parts by weight,

the cleaning agent consists of the following components in percentage by weight,

the performance indexes of the torch liquid separating tank before cleaning are as follows:

1. the dirt deposited in the torch liquid separating tank accounts for 43 percent of the volume in the tank, so that the performance of the torch liquid separating tank is reduced by 50 percent under the condition of normal operation.

2. The torch liquid separating tank takes sulfur scale as main acidic dirt to cause chemical corrosion to the tank wall, so that the service life of the torch liquid separating tank is shortened by 45 percent.

3. Because the torch liquid separating tank mainly deposits the acid dirt, the protective effect of the corrosion inhibitor in the gas gathering station system process on the tank wall is weakened, and the corrosion inhibitor in the system is wasted by 20 percent.

The photograph is shown in FIG. 3.

The performance indexes of the cleaned torch shunt tank are as follows:

1. after the sulfur scale deposited in the torch liquid separating tank is removed, the torch liquid separating tank is restored to the optimal service performance state, the service performance is improved by 50% compared with the service performance before cleaning, and meanwhile, the working efficiency of the gas collecting station is improved by 30%.

2. After the torch liquid separating tank is mainly used for removing acid dirt, the inner part of the tank wall is not corroded under the dirt, and the inner wall of the torch liquid separating tank is passivated and protected when in use, so that the service life of the torch liquid separating tank is prolonged by 40%.

3. After the torch liquid separating tank is deposited and cleaned by acid dirt mainly comprising sulfur dirt, the wall of the tank is protected by the corrosion inhibitor in use, so that a gas gathering station system is more stable in operation.

The photograph is shown in FIG. 4.

The time taken for cleaning the torch shunt tank was 3 days.

Experimental example 2 the process provided by the invention is adopted to carry out metering separation in a Sichuan common light gas gathering station Cleaning the device

The operation steps are as follows:

(1) opening an inlet valve and an outlet valve of the bypass device, closing the inlet valve and the outlet valve of the metering separator, and adjusting natural gas in the original pipeline to flow into downstream equipment through the bypass device;

(2) communicating the sand washing skid with the metering separator;

(2') injecting a first passivating agent into the sand washing agent tank, starting an electric heating device to heat the first passivating agent to 75 ℃, enabling the heated first passivating agent to flow through a metering separator, circularly flowing and washing for 30min, starting a diaphragm pump, and emptying the first passivating agent;

(3) injecting a cleaning agent into the sand washing agent tank, opening the electric heating device, heating the cleaning agent to 75 ℃, soaking and washing the interior of the metering separator by the cleaning agent, monitoring the pressure difference between a sand washing port and a waste liquid port of the metering separator, opening a reverse washing pipeline by an adjusting valve when the pressure difference is continuously increased, closing the reverse washing pipeline by the adjusting valve when the pressure difference is stabilized at a constant value, continuously washing in the forward direction for a plurality of times, and stopping washing until the pressure difference is close to 0;

(4) after the interior of the cleaning equipment is cleaned, opening the diaphragm pump, emptying the cleaning agent in the metering separator, injecting clean water into the sand washing agent tank, opening the electric heating device, heating the clean water to 80 ℃, enabling the clean water to flow through the torch liquid separating tank, monitoring the pH value of the clean water flowing back from the return port of the sand washing agent tank, and stopping the clean water washing when the pH value is 7;

(5) opening the diaphragm pump, emptying clear water, closing the sand washing port and the waste liquid port of the metering separator, opening the passage valve of the metering separator, closing the valve of the bypass device, and removing the connection between the sand washing skid-mounted device and the sand washing port and the waste liquid port of the metering separator.

the performance indexes of the metering separator before cleaning are as follows:

1. the dirt deposited inside the metering separator accounts for up to 38% of the volume in the tank, so that the performance of the metering separator is reduced by 45% under the normal operation condition.

2. The metering separator takes sulfur scale as main acidic dirt to cause chemical corrosion to the tank wall, so that the service life of the metering separator is seriously shortened by 40 percent.

3. Because the metering separator mainly deposits the acid dirt, the protective effect of the corrosion inhibitor in the gas station system process on the tank wall is weakened, and the corrosion inhibitor in the system is wasted by 18 percent.

The performance indexes of the cleaned metering separator are as follows:

1. after the sulfur scale deposited in the metering separator is removed, the metering separator is recovered to the optimal service performance state, the service performance is improved by 45% compared with the service performance before cleaning, and meanwhile, the working efficiency of the gas gathering station is improved by 28%.

2. After the metering separator removes acid dirt mainly containing sulfur dirt, the inner part of the tank wall is not corroded under the dirt, and the inner wall of the metering separator is passivated and protected when in use, so that the service life of the metering separator is prolonged by 38%.

3. After the metering separator is deposited and cleaned by acid dirt mainly containing sulfur scale, the tank wall is protected by the corrosion inhibitor from time to time when the metering separator is used, so that a gas gathering station system is more stable in operation.

The time taken to clean the metering separator was 2 days.

Experimental example 3 the process provided by the invention is adopted to buffer acid liquor in a Sichuan common light gas gathering station Tank cleaning

The operation steps are as follows:

(1) opening an inlet and outlet valve of the bypass device, closing an inlet and outlet valve of the acid liquor buffer tank, and adjusting natural gas in the original pipeline to flow into downstream equipment through the bypass device;

(2) the sand washing skid is communicated with the acid liquor buffer tank;

(2') injecting a first passivating agent into the sand washing agent tank, starting an electric heating device, heating the first passivating agent to 80 ℃, enabling the heated first passivating agent to flow through an acid liquor buffer tank, circularly flowing and washing for 30min, starting a diaphragm pump, and emptying the first passivating agent;

(3) injecting a cleaning agent into the sand washing agent tank, opening the electric heating device, heating the cleaning agent to 75 ℃, soaking and washing the interior of the acid liquor buffer tank by the cleaning agent, monitoring the pressure difference between a sand washing port and a waste liquid port of the acid liquor buffer tank, adjusting the valve to open the reverse washing pipeline when the pressure difference is continuously increased, adjusting the valve to close the reverse washing pipeline when the pressure difference is stabilized at a constant value, continuously washing in the forward direction for a plurality of times, and stopping washing until the pressure difference is close to 0;

(4) after the interior of the cleaning equipment is cleaned, opening the diaphragm pump, emptying the cleaning agent in the acid liquor buffer tank, injecting clean water into the sand washing agent tank, opening the electric heating device, heating the clean water to 70 ℃, enabling the clean water to flow through the torch liquid separating tank, monitoring the pH value of the clean water flowing back from the return port of the sand washing agent tank, and stopping the clean water washing when the pH value is 9;

(5) opening the diaphragm pump, emptying clear water, closing the sand washing port and the waste liquid port of the acid liquor buffer tank, opening the access valve of the acid liquor buffer tank, closing the valve of the bypass device, and removing the connection between the sand washing skid-mounted device and the sand washing port and the waste liquid port of the acid liquor buffer tank.

the performance index of the acid liquor buffer tank before cleaning is as follows

1. The dirt deposited in the acid liquor buffer tank accounts for 35% of the inner volume of the tank, so that the performance of the acid liquor buffer tank is reduced by 30% under the condition of normal operation.

2. The acid liquor buffer tank takes sulfur scale as main acidic dirt to cause chemical corrosion to the tank wall, so that the service life of the acid liquor buffer tank is shortened by 30 percent seriously.

3. Because the acid liquor buffer tank mainly deposits the sulfur scale as the main acidic dirt, the protective effect of the corrosion inhibitor inside the gas gathering station system process on the tank wall is weakened, and the corrosion inhibitor inside the system is wasted by 40%.

The photograph is shown in FIG. 5.

The performance indexes of the acid liquid buffer tank after cleaning are as follows:

1. after the sulfur scale deposited in the acid liquor buffer tank is removed, the acid liquor buffer tank is restored to the optimal service performance state, the service performance is improved by 30% compared with the service performance before cleaning, and meanwhile, the working efficiency of the gas gathering station is improved by 25%.

2. After the acid liquor buffer tank mainly removes the sulfur scale, the inner part of the tank wall is not corroded under the scale, and the inner wall of the acid liquor buffer tank is passivated and protected when in use, so that the service life of the acid liquor buffer tank is prolonged by 28 percent.

3. After the acid liquor buffer tank is deposited and cleaned by acid dirt mainly comprising sulfur dirt, the tank wall is protected by the corrosion inhibitor from time to time when the acid liquor buffer tank is used, so that a gas gathering station system is more stable in operation.

The photograph is shown in FIG. 6.

The time for cleaning the acid liquor buffer tank is 3 days.

The invention has been described in detail with reference to specific embodiments and illustrative examples, but the description is not intended to be construed in a limiting sense. Those skilled in the art will appreciate that various equivalent substitutions, modifications or improvements may be made to the technical solution of the present invention and its embodiments without departing from the spirit and scope of the present invention, which fall within the scope of the present invention. The scope of the invention is defined by the appended claims.

Claims

1. A sand washing and cleaning process for a gas gathering station of a high-sulfur-content gas field is characterized by comprising the following steps of:

(2) communicating the sand washing skid with equipment to be cleaned;

2. The process of claim 1, further comprising, after step 2 and before step 3,

3. The process according to claim 1 or 2,

the sand washing skid-mounted device comprises a sand washing agent tank (1) arranged on a transport vehicle; the sand washing agent tank (1) is provided with a medicine inlet (11), a medicine outlet (12), a first backflow port (131) and a second backflow port (132).

4. Process according to any one of claims 1 to 3, characterized in that the sand washing skid further comprises a sand washing water pump (3), a diaphragm pump (4), a filter separator (5), a cyclone separator (6) and a circulation pump (7), wherein,

the sand washing water pump (3) is arranged between the medicine outlet (13) and a sand washing port (21) of the equipment to be cleaned; and/or

One end of the diaphragm pump (4) is communicated with a pipeline between the waste liquid port (22) of the equipment to be cleaned and the filtering separator (5); the other end is communicated with a pipeline between the filtering separator (5) and the circulating pump (7); and/or

The filtering separator (5) is arranged between a waste liquid port (22) of the equipment to be cleaned and a first backflow port (131) of the sand washing agent tank (1); and/or

The cyclone separator (6) is arranged between the filtering separator (5) and the first backflow port (131) of the sand washing agent tank (1); and/or

The circulating pump (7) is arranged between the filtering separator (5) and the cyclone separator (6).

5. The process according to any one of claims 1 to 4, wherein the sand washing skid further comprises a back-flush line comprising a back-inlet pipe (23) and a back-outlet pipe (24), wherein,

one end of the reverse liquid inlet pipe (23) is communicated with a pipeline between the sand washing water pump (3) and the sand washing port (21) of the equipment to be cleaned, the other end of the reverse liquid inlet pipe is communicated with a pipeline between the waste liquid port (22) of the equipment to be cleaned and the filtering separator (5), and a valve is arranged on the reverse liquid inlet pipe; and/or

One end of the reverse liquid outlet pipe (24) is communicated with a medicament backflushing reserved port (25) on the equipment to be cleaned, and the other end of the reverse liquid outlet pipe is communicated with a second backflow port (132) on the sand washing medicament tank.

6. The process according to any one of claims 1 to 5, wherein the sand washing agent tank (1) further comprises a breather valve (14), an electric heating device (15), a first liquid level meter (16), a second liquid level meter (17), a slag removal opening (18), a sewage discharge opening (19), an industrial observation mirror (110) and/or a pH detector (111), wherein,

the breather valve (14) is arranged at the top of the sand washing agent tank (1); and/or

The electric heating device (15) is arranged inside the sand washing agent tank (1); and/or

The first liquid level meter (16) is arranged inside the sand washing agent tank (1); and/or

The second liquid level meter (17) is arranged in the middle of the right side wall of the sand washing agent tank (1); and/or

The deslagging opening (18) is arranged at the bottom of the right side of the sand washing agent tank (1); and/or

The sewage outlet (19) is arranged at the bottom of the left side of the sand washing agent tank (1); and/or

The industrial observation mirror (110) is arranged in the middle of the left side wall of the sand washing agent tank (1); and/or

The pH detector (111) is arranged in the middle of the left side wall of the sand washing agent tank (1), below the industrial observation mirror (110) and above the electric heating device (15); and/or

The sand washing agent tank is characterized in that a medicine outlet (12) of the sand washing agent tank is communicated with a sand washing port (21) of equipment to be cleaned, so that a first backflow port (131) of the sand washing agent tank is communicated with a waste liquid port (22) of the equipment to be cleaned.

7. The process according to any one of claims 1 to 6, wherein in step 2', the first passivating agent is prepared from the following components in parts by weight,

8. the process as claimed in any one of claims 1 to 7, wherein in step 4, the cleaning agent is prepared from the following components in parts by weight,

5-10 parts of sulfur dissolving agent

3-15 parts of dispersant

1-18 parts of a complexing agent;

wherein,

9. The process according to any one of claims 1 to 8, wherein a medicine outlet (12) of the sand washing agent tank (1) is connected with a sand washing port (21) of equipment to be cleaned through a high-pressure rubber pipe, and one end of the high-pressure rubber pipe, which is communicated with the equipment to be cleaned, is provided with a high-pressure rubber pipe adapting quick connector.

10. The process according to any one of claims 1 to 9,

In the step 2, the needed medicament is added into the sand washing medicament tank (1) through the medicament inlet (11) when the equipment is cleaned, the medicament in the sand washing medicament tank (1) is injected into the equipment to be cleaned through a sand washing port (21) of the equipment to be cleaned, and after the inside of the equipment to be cleaned is cleaned, the medicament flows out through a waste liquid port (22) of the equipment to be cleaned, is regenerated and is injected into the sand washing medicament tank 1 again through a first backflow port (131) for recycling; and/or

When the equipment to be cleaned is subjected to reverse flushing operation, the medicament in the equipment to be cleaned flows out from the medicament backflushing reserved opening (25), and is directly injected into the sand washing medicament tank (1) through the second backflow opening (132) without being processed for recycling; and/or

In the sand washing agent tank, the agent in the sand washing agent tank (1) is heated by an electric heating device (15), preferably to 70-80 ℃; and/or

In the step 3, monitoring the pH value of the cleaning agent in the sand washing agent tank (1) to keep the pH value of the cleaning agent at 9-13, preferably 10-12; and/or

Monitoring the liquid level height of a cleaning agent in the sand washing agent tank 1, and supplementing the cleaning agent into the sand washing agent tank 1 when the cleaning agent is lower than the preset liquid level height; when the cleaning agent is higher than the preset liquid level height, opening a drain outlet (19) of the sand washing agent tank (1) to enable the liquid level height of the cleaning agent to be within the range of the preset liquid level height; and/or

Monitoring the pressure of a cleaning agent entering a sand washing port (21) of the equipment to be cleaned, simultaneously monitoring the pressure of waste liquid flowing out of a waste liquid port (22) of the equipment to be cleaned, and stopping cleaning the equipment to be cleaned when the pressure of the waste liquid is close to or equal to the pressure at the sand washing port (21); and/or

In the step 4, after the interior of the equipment to be cleaned is cleaned and the inner wall of the equipment to be cleaned is fully passivated, a drain outlet (19) of the sand washing agent tank (1) is opened to discharge the cleaning agent in the sand washing agent tank, and meanwhile, the diaphragm pump (4) is optionally opened to discharge the residual cleaning agent in the equipment to be cleaned out of the equipment to be cleaned as much as possible; and/or

Monitoring the pH value of backflow water at a first backflow port (131) of the sand washing agent tank (1), and stopping injecting clear water into the equipment to be cleaned when the pH value of the backflow water reaches 7-9; and/or

And (3) in any step of the step (1) to the step (5), the solid impurities separated by the filtering separator (5) and the cyclone separator (6) are collected and recovered, preferably, the solid impurities are pressed and filtered into blocks and are recycled.