阅读说明：本技术 一种油基钻屑热脱附挥发份分离收集系统及工艺 (Oil-based drilling cutting thermal desorption volatile separation and collection system and process ) 是由 许世佩 邵志国 许毓 李兴春 任雯 刘龙杰 孙静文 于 2020-04-17 设计创作，主要内容包括：本发明提供了一种油基钻屑热脱附挥发份分离收集系统及工艺,所述系统包括过滤除尘装置、挥发份冷凝分离装置、不凝气处理装置、油水收集分离装置、油罐及水罐；油水收集分离装置包括若干个并联设置且依次开启的油水分离器；过滤除尘装置的出口通过管路经由挥发份冷凝分离装置与不凝气处理装置的入口相连,挥发份冷凝分离装置的液体出口通过管路与若干个并联设置的油水分离器的总油水入口相连；若干个油水分离器的油出口分别通过管路与油罐相连；若干个油水分离器的水出口分别通过管路与水罐相连。本发明所提供的该系统及工艺可实现油基钻屑热脱附油水的批量收集及连续稳定作业,降低了停机检修频率和等待分离时间,避免了间歇性处理对系统的冲击。(The invention provides a thermal desorption volatile matter separation and collection system and a thermal desorption volatile matter separation and collection process for oil-based drilling cuttings, wherein the system comprises a filtering and dust removal device, a volatile matter condensation and separation device, a non-condensable gas treatment device, an oil-water collection and separation device, an oil tank and a water tank; the oil-water collecting and separating device comprises a plurality of oil-water separators which are arranged in parallel and are sequentially opened; an outlet of the filtering and dust removing device is connected with an inlet of the non-condensable gas processing device through a volatile matter condensation separation device through a pipeline, and a liquid outlet of the volatile matter condensation separation device is connected with a total oil-water inlet of a plurality of oil-water separators which are arranged in parallel through pipelines; the oil outlets of the oil-water separators are respectively connected with the oil tank through pipelines; the water outlets of the oil-water separators are respectively connected with the water tank through pipelines. The system and the process provided by the invention can realize batch collection and continuous and stable operation of thermal desorption oil and water of the oil-based drilling cuttings, reduce the shutdown maintenance frequency and the waiting separation time, and avoid the impact of intermittent treatment on the system.)

1. The utility model provides an oil base drill chip thermal desorption volatile separation collecting system which characterized in that, oil base drill chip thermal desorption volatile separation collecting system includes:

a filtering and dust removing device, a volatile matter condensation and separation device, a non-condensable gas treatment device, an oil-water collection and separation device, an oil tank and a water tank; the oil-water collecting and separating device comprises a plurality of oil-water separators which are arranged in parallel and are sequentially opened;

an outlet of the filtering and dust removing device is connected with an inlet of the volatile matter condensation and separation device through a pipeline, a gas outlet of the volatile matter condensation and separation device is connected with an inlet of the non-condensable gas treatment device through a pipeline, and a liquid outlet of the volatile matter condensation and separation device is connected with a total oil-water inlet of a plurality of oil-water separators which are arranged in parallel through pipelines;

the oil outlets of the oil-water separators are respectively connected with the oil tank through pipelines; and the water outlets of the oil-water separators are respectively connected with the water tank through pipelines.

2. The system of claim 1, wherein the fuel water separator is a siphonic fuel water separator, the siphonic fuel water separator comprising: the top of the liquid storage cavity is provided with an oil-water inlet, an oil outlet and a gas inlet and outlet; a water outlet is formed in the bottom of the liquid storage cavity; a buoyancy liquid discharging ball is arranged in the liquid storage cavity, an oil inlet is formed right above the buoyancy liquid discharging ball, an oil outlet is formed in the side wall of the buoyancy liquid discharging ball, the oil outlet of the buoyancy liquid discharging ball is connected with an oil discharging hose, and the oil discharging hose extends out of the liquid storage cavity through the oil outlet of the liquid storage cavity;

the oil-water inlet and the water outlet are respectively provided with an inlet valve and an outlet valve.

3. The system of claim 2, wherein a side wall of the reservoir chamber is provided with an opening for attachment of a liquid level gauge.

4. The system of claim 2, wherein the siphon-type oil-water separator further comprises a multi-way valve, one opening of the multi-way valve is connected with the gas inlet and outlet, and any two of the other openings of the multi-way valve are respectively connected with an air inlet pipeline and an exhaust pipeline.

5. The system of claim 4, wherein the multi-way valve is a three-way valve, one opening of the three-way valve is connected to the gas inlet and outlet, and the other two openings are connected to an air inlet pipeline and an exhaust pipeline respectively.

6. The system of claim 2, wherein the siphon oil-water separator further comprises an oil drain pipe, and one end of the oil drain pipe extends into the liquid storage cavity through the oil outlet of the liquid storage cavity and is connected with the oil drain hose.

7. The system of claim 2, wherein the bottom of the reservoir chamber is funnel shaped in a cone, the bottom of the funnel forming the water outlet.

8. The system according to any one of claims 1 to 7, wherein the gas outlet of the non-condensable gas processing device is connected with the filtering and dust removing device through a pipeline, and the dust is removed by a back-blowing filtering and dust removing device.

9. The system of any of claims 1-7, wherein the number of oil water separators is three.

10. The system as claimed in any one of claims 1 to 7, further comprising a three-phase disc separator, wherein the water outlets of the plurality of oil-water separators are further connected with the three-phase disc separator through pipelines respectively, so as to feed the oil-water mixture and impurities at the oil-water interface of the plurality of oil-water separators into the three-phase disc separator for three-phase separation; and an oil outlet and a water outlet of the three-phase disc separator are respectively connected with the oil tank and the water tank through pipelines.

11. The system according to any one of claims 1 to 7, further comprising a filtering device, wherein the water outlets of the plurality of oil water separators are respectively connected to the water tank through the filtering device by pipelines.

12. The system of claim 11, wherein the water outlet of the water tank is further connected to the filtering device by a pipeline to back flush the filtering device, and the resulting back flush water flows into the three-phase disk separator through the pipeline.

13. The system according to any one of claims 1 to 7, wherein the filter dust removing device is a filter dust removing device provided with a heat tracing device.

14. A thermal desorption volatile separation and collection process for oil-based drill cuttings, which is realized by using the thermal desorption volatile separation and collection system for oil-based drill cuttings according to any one of claims 1 to 13, and comprises the following steps:

(1) carrying out dust removal on the volatile matters of the oil-based drilling cuttings by thermal desorption in a filtering and dust removing device to obtain dust-free volatile matters;

(2) carrying out gas-liquid separation on the dust-free volatile matter in a volatile matter condensation separation device to obtain noncondensable gas and condensate;

(3) treating the non-condensable gas in the non-condensable gas treatment device;

(4) and carrying out uninterrupted oil-water separation on the condensate in an oil-water collecting and separating device, and respectively storing the separated oil and water for later use.

15. The process of claim 14, further comprising: and (3) performing three-phase separation on an oil-water mixture and impurities at an oil-water interface in the oil-water separation process in a three-phase disc separator, wherein oil and water obtained after the three-phase separation are respectively stored in an oil tank and a water tank, and an obtained solid phase is discarded in a residue soil pile.

16. The process according to claim 14 or 15, further comprising: and (4) utilizing the treated non-condensable gas back-blowing filtering dust removal device to remove dust, and discarding the dust obtained by back-blowing in a residue soil pile.

Technical Field

The invention relates to a thermal desorption volatile matter separation and collection system and process for oil-based drilling cuttings, and belongs to the technical field of oil-containing solid waste recycling treatment in the petrochemical industry.

Background

In recent years, the main attack direction of oil fields in China is to develop shale gas on a large scale, oil-based mud is used for drilling in the process of exploiting the shale gas, a large amount of drill cuttings are generated by rocks in a drill bit cutting stratum, the drill cuttings are brought to the ground through the carrying effect of the oil-based mud, so that the oil-based drill cuttings are formed and listed in a national hazardous waste list (HW08), and if the oil-based drill cuttings are directly discharged without being processed, serious harm is caused to the surrounding ecological environment. Among the methods for treating oil-based drilling cuttings in the market at present, the thermal desorption process becomes a hot spot technology due to the outstanding advantages of short treatment period, high oil removal efficiency and the like. The thermal desorption process is mainly characterized in that under the anaerobic condition, materials are heated in a thermal desorption furnace, so that the temperature of volatile substances in the materials reaches the boiling point, and the volatile substances are evaporated and removed from the materials. The treatment method has obvious effect of removing oil in the oil-based drill cuttings, the oil content of the treated residues can be reduced to below 0.3%, and hydrocarbon resources in the drill cuttings can be recycled.

Related thermal desorption equipment is designed and manufactured by a plurality of units in China, and is popularized and applied to partial oil fields. At present, the thermal desorption equipment of the oil-based drilling cuttings is intensively researched and relatively perfected, however, the thermal desorption process has some places which need to be optimized and perfected at present in the collection and separation process of volatile matters. The volatile matters desorbed from the thermal desorption are complex in composition, comprise various components such as thermal desorption oil, thermal desorption gas, water vapor and the like, and simultaneously carry dust escaping from the reactor, so that the separation and collection of the volatile matters cannot be properly processed, and various problems such as subsequent pipeline blockage and the like can be caused. Therefore, the efficient separation and collection of the volatile matters is a key link of the safe, stable and continuous operation of the whole process flow. The reasonably designed volatile matter collecting and separating unit can meet the requirements of high efficiency of material thermal desorption products with different properties, low energy consumption separation is realized, the maintenance frequency is reduced, and the stable operation of a thermal desorption system is realized.

At present, the patents of special research on the recovery process and device of volatile matters of oil-based drill cuttings are few, and Chinese invention patent CN109267953A relates to a method and a device for recovering mud and base oil in waste oil-based drilling fluid in a grading manner. This process does not address the problem of clogging of the filter element by dust particles carried by volatiles produced in the upstream flow, and frequent filter element replacement is detrimental to overall process cost control. The invention patent CN102794033A relates to an oil-gas-water three-phase hypergravity separator, which utilizes hypergravity, has large energy consumption, is suitable for separating oil-water mixtures with small density difference and difficult separation, or places with strict requirements on equipment size or separation time, and has high operation and maintenance cost which is obviously not suitable for oil-water separation of oil-based drilling cutting industrial equipment.

To sum up, to the problems that the existing oil-based drilling cutting oil-water separation device has high energy consumption, large space and high equipment maintenance cost, and does not realize continuous operation and the like, the development of a novel oil-based drilling cutting thermal desorption volatile matter separation and collection system and process has become a technical problem to be solved urgently in the field.

Disclosure of Invention

In order to solve the disadvantages and shortcomings, the invention provides a thermal desorption volatile matter separation and collection system for oil-based drill cuttings.

The invention also aims to provide a process for separating and collecting the volatile matters of the oil-based drill cuttings through thermal desorption.

In order to achieve the above object, in one aspect, the present invention provides an oil-based drill cuttings thermal desorption volatile matter separation and collection system, wherein the oil-based drill cuttings thermal desorption volatile matter separation and collection system comprises:

a filtering and dust removing device, a volatile matter condensation and separation device, a non-condensable gas treatment device, an oil-water collection and separation device, an oil tank and a water tank; the oil-water collecting and separating device comprises a plurality of oil-water separators which are arranged in parallel and are sequentially opened;

an outlet of the filtering and dust removing device is connected with an inlet of the volatile matter condensation and separation device through a pipeline, a gas outlet of the volatile matter condensation and separation device is connected with an inlet of the non-condensable gas treatment device through a pipeline, and a liquid outlet of the volatile matter condensation and separation device is connected with a total oil-water inlet of a plurality of oil-water separators which are arranged in parallel through pipelines;

the oil outlets of the oil-water separators are respectively connected with the oil tank through pipelines; and the water outlets of the oil-water separators are respectively connected with the water tank through pipelines.

In the above system, preferably, the oil-water separator is a siphon oil-water separator, and the siphon oil-water separator includes: the top of the liquid storage cavity is provided with an oil-water inlet, an oil outlet and a gas inlet and outlet; a water outlet is formed in the bottom of the liquid storage cavity; a buoyancy liquid discharging ball is arranged in the liquid storage cavity, an oil inlet is formed right above the buoyancy liquid discharging ball, an oil outlet is formed in the side wall of the buoyancy liquid discharging ball, the oil outlet of the buoyancy liquid discharging ball is connected with an oil discharging hose, and the oil discharging hose extends out of the liquid storage cavity through the oil outlet of the liquid storage cavity;

the oil-water inlet and the water outlet are respectively provided with an inlet valve and an outlet valve.

In the system described above, preferably, the side wall of the liquid storage cavity is provided with an opening for connecting a liquid level meter.

In the above system, preferably, the siphon oil-water separator further includes a multi-way valve, one opening of the multi-way valve is connected to the gas inlet and outlet, and any two openings of the other openings of the multi-way valve are respectively connected to an air inlet pipeline and an exhaust pipeline.

In the above system, preferably, the multi-way valve is a three-way valve, one opening of the three-way valve is connected to the gas inlet and outlet, and the other two openings are respectively connected to an air inlet pipeline and an exhaust pipeline.

In the system described above, preferably, the siphon oil-water separator further includes an oil drain pipe, and one end of the oil drain pipe extends into the liquid storage cavity via the oil outlet of the liquid storage cavity, and is connected to the oil drain hose.

In the system described above, preferably, the bottom of the liquid storage cavity is a conical funnel shape, and the bottom of the funnel shape forms a water outlet.

In the system described above, preferably, the gas outlet of the non-condensable gas processing device is connected to the filtering and dust removing device through a pipeline, and the dust is removed by the back-flushing filtering and dust removing device.

In the system described above, preferably, the number of the oil water separators is three.

In the system, the oil-water collecting and separating device comprises a plurality of oil-water separators which are arranged in parallel and are sequentially opened, so that the oil-water separation can be realized by uninterrupted circulation; if the number of the oil-water separators is three, one of the oil-water separators is in a condensate collecting state, the other oil-water separator is in a standing state for waiting for oil-water separation, and the other oil-water separator is in an oil-water discharging state, so that the oil-water separation can be continuously and circularly carried out.

In the system, the buoyancy drain ball, the oil drain hose, the liquid level meter, the oil drain pipe and other equipment used in the siphon oil-water separator are conventional equipment.

In addition, in the siphon oil-water separator, "connection" and "connection" are both sealed connection and sealed connection, for example, the connection between the oil outlet of the buoyancy drain ball and the oil drain hose, the connection between the side wall opening of the liquid storage cavity and the liquid level meter, the connection between the oil drain pipe and the oil drain hose, and the like;

in addition, when the oil discharge hose extends out of the liquid storage cavity through the oil outlet of the liquid storage cavity or one end of the oil discharge pipe extends into the liquid storage cavity through the oil outlet of the liquid storage cavity, the oil discharge hose or the oil discharge pipe and the oil outlet of the liquid storage cavity need to be sealed.

Preferably, the system further comprises a three-phase disc separator, and the water outlets of the oil-water separators are respectively connected with the three-phase disc separator through pipelines so as to send oil-water mixtures and impurities at oil-water interfaces of the oil-water separators into the three-phase disc separator for three-phase separation; and an oil outlet and a water outlet of the three-phase disc separator are respectively connected with the oil tank and the water tank through pipelines.

Preferably, the system further comprises a filtering device, and the water outlets of the oil-water separators are respectively connected with the water tank through the filtering device through pipelines.

In the system, preferably, the water outlet of the water tank is further connected with the filtering device through a pipeline to perform back washing on the filtering device, and the obtained back washing water flows into the three-phase disc separator through the pipeline.

In the system described above, preferably, the filter dust removing device is a filter dust removing device provided with a heat tracing device.

Wherein, the filtering and dust removing device is provided with the heat tracing device, which can maintain the temperature of the oil gas to be higher than the condensation temperature, so that the oil gas smoothly passes through the filtering and dust removing device and most of dust can be removed.

In the system, a filtering and dust removing device, a volatile matter condensation and separation device, a non-condensable gas treatment device, an oil-water collection and separation device, an oil tank, a water tank, a three-phase disc separator, a heat tracing device, a filtering device and the like are conventional equipment.

In the system described above, "connect" or "link to each other" between each part is sealing connection and sealing connection, if the export of filtering dust collector with link to each other between volatile matter condensation separator's the entry, volatile matter condensation separator's gas outlet with link to each other between noncondensable gas processing apparatus's the entry, volatile matter condensation separator's liquid outlet and a plurality of parallel arrangement link to each other between oil water separator's the total oily water inlet etc. and are sealing connection.

In another aspect, the invention further provides a process for separating and collecting thermal desorption volatile components of oil-based drill cuttings, wherein the process is implemented by using the system for separating and collecting thermal desorption volatile components of oil-based drill cuttings, and the process comprises the following steps:

(1) carrying out dust removal on the volatile matters of the oil-based drilling cuttings by thermal desorption in a filtering and dust removing device to obtain dust-free volatile matters;

(2) carrying out gas-liquid separation on the dust-free volatile matter in a volatile matter condensation separation device to obtain noncondensable gas and condensate;

(3) treating the non-condensable gas in the non-condensable gas treatment device;

(4) and carrying out uninterrupted oil-water separation on the condensate in an oil-water collecting and separating device, and respectively storing the separated oil and water for later use.

Preferably, the process further comprises: and (3) performing three-phase separation on an oil-water mixture and impurities at an oil-water interface in the oil-water separation process in a three-phase disc separator, wherein oil and water obtained after the three-phase separation are respectively stored in an oil tank and a water tank, and an obtained solid phase is discarded in a residue soil pile.

Preferably, the process further comprises: and the processed noncondensable gas is used for carrying out dust removal by a back-blowing filtering and dust removing device, and the dust obtained by back-blowing is discharged from a dust discharging port of the filtering and dust removing device and then is discarded in a residue soil pile.

In the above process, when the oil-water separator is a siphon oil-water separator, the oil-water separation process in the process specifically includes the following steps:

and opening the inlet valve, closing the outlet valve and communicating the three-way valve with the exhaust pipeline, so that the thermal desorption condensate of the oil-based drilling cuttings flows into the liquid storage cavity through the oil-water inlet.

Observing the liquid level meter, closing the inlet valve after the liquid storage cavity is filled with the condensate, and standing for oil-water gravity settling separation. Wherein, the density of the thermal desorption oil is 0.83-0.88g/mL, the density of water is 1g/mL, and the thermal desorption oil has strong hydrophobicity and is very suitable for gravity sedimentation.

After the oil and water are subjected to gravity settling separation, the three-way valve is communicated with the air inlet pipeline, and gas (such as non-condensable gas treated by the non-condensable gas treatment device) is introduced into the liquid storage cavity from the air inlet pipeline and serves as initial driving gas of a siphon effect. And after the siphon effect is formed, the three-way valve is communicated with the exhaust pipeline. The supernatant oil (thermal desorption oil) enters the buoyancy liquid discharging ball and flows into the oil tank through the oil discharging hose and the oil discharging pipe. After the supernatant liquid is drained completely, the outlet valve is opened to allow the lower layer clear water to flow out, the front segment clear water is directly filled into the water tank through filtration, and a small amount of oil-water mixture and impurities on the interface enter the three-phase disc separator.

In the above step (3), the step of treating the non-condensable gas in the non-condensable gas treatment device means that the non-condensable gas treatment device converts combustible gas in the non-condensable gas into non-combustible gas by means of catalytic oxidation (the method is high in cost and mainly suitable for places where open fire is forbidden in a well site) or combustion, and the non-condensable gas is discharged after being desulfurized and denitrated to meet the environmental protection requirement.

In the system and the process, the siphon oil-water separator realizes oil-water separation without external power (such as oil-based drilling cuttings thermal desorption oil-water) by utilizing gravity settling and siphoning phenomena, and has the advantages of convenient and quick process and low energy consumption; meanwhile, the oil is taken out from the upper end of the siphon-type oil-water separator, the water is taken out from the lower end of the siphon-type oil-water separator, the back mixing is small, the disturbance of an oil-water separation interface is small, the purity of the separated oil-water is high, and different liquid storage cavities can be set in different sizes to adapt to different process treatment amounts and realize the batch collection of the oil-water.

In the system and the process, the volume of different liquid storage cavities can be set to meet the requirements of different process treatment capacities; through setting up a plurality of siphon oil water separator and connecting in parallel, seamless switching can realize oil base drill chip thermal desorption profit's batch collection and continuous stable operation, has reduced and has shut down maintenance frequency and wait for the separation time, has avoided intermittent type nature to handle the impact of system.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a siphon oil-water separator according to embodiment 1 of the present invention.

Fig. 2 is a schematic structural diagram of an oil-based drill cutting thermal desorption volatile separation and collection system provided in embodiment 2 of the present invention.

The main reference numbers illustrate:

1. an inlet valve;

2. a liquid storage cavity;

3. an exhaust line;

4. an air intake line;

5. a buoyant liquid discharge ball;

6. an oil drain hose;

7. an oil discharge pipe;

8. a liquid level meter;

9. an outlet valve;

10. a three-way valve;

11. a filtering and dust removing device;

12. a volatile matter condensation separation device;

13. a noncondensable gas treatment device;

14. an oil-water collecting and separating device;

141. a first siphon oil-water separator;

142. a second siphon oil-water separator;

143. third siphon type oil-water separator

15. A three-phase disc separator;

16. a filtration device;

17. an oil tank;

18. a water tank;

19. stacking the residue soil;

20. a heat tracing device.

Detailed Description

In order to clearly understand the technical features, objects and advantages of the present invention, the following detailed description of the technical solutions of the present invention will be made with reference to the following specific examples, which should not be construed as limiting the implementable scope of the present invention.