CN107376581A - A kind of flaring cyclone-type supersonic nozzle - Google Patents

Abstract

The present invention proposes a gradually expanding swirl type supersonic nozzle, the technical scheme: including the inlet of the nozzle, the tapering section of the nozzle, the throat of the nozzle, the expanding section of the nozzle, the outlet of the nozzle, and the Cyclone etc. Natural gas containing water vapor and heavy hydrocarbon components enters the converging section of the nozzle through the inlet of the nozzle to expand and cool down, and then expands to supersonic speed after passing through the throat of the nozzle. into droplets, and then through the cyclone in the expanding section of the nozzle, high-speed swirling flow is realized under supersonic conditions, and the huge centrifugal force generated by the swirling flow throws the droplets to the wall of the nozzle, where they are separated or absorbed in the subsequent process, thus Realize gas-liquid separation. The beneficial effects are: simple structure, convenient processing, easy realization of condensation and swirl separation of water and heavy hydrocarbons, avoiding the shock wave effect and secondary evaporation of condensed droplets, and can replace the traditional supersonic separator to realize the dehydration of natural gas , Heavy hydrocarbon removal and other complex processes.

Description

A Supersonic Nozzle with Expanding Swirling Flow

technical field

The invention relates to a gradually expanding and swirling supersonic nozzle, which is mainly used for removing water and heavy hydrocarbon components in natural gas, and belongs to the technical field of natural gas processing and treatment.

Background technique

With the rapid development of social economy, the demand for natural gas is increasing day by day. Before natural gas is exported and used, dehydration and heavy hydrocarbon removal processes are required. Supersonic cyclone separation technology is an emerging natural gas processing technology this year. It is widely used in the fields of natural gas dehydration and heavy hydrocarbon removal. Development and utilization are of great significance.

Abroad, the Dutch Shell Petroleum Company has developed the research on natural gas supersonic separation technology, including basic theoretical research, numerical simulation, laboratory research and field test research. Representative patents include US 6513345B1, US6524368B2, US 3773825B2, US 6962199B1, US 7261766B2, US 7318849B2, US 7494535B2, etc. The research institutes of Eindhoven University of Technology, Stork Product Engineering and Shell in the Netherlands have developed a number of analytical and numerical simulation tools to describe the complex flow inside the separator. TwisterBV has installed a set of test equipment to study the treatment of rich natural gas, and the test plant in Nigeria has started operation, successfully dehydrating 850,000 cubic meters per day of natural gas to the standard required by the pipeline.

Domestic China University of Petroleum (East China), Beijing University of Technology, Dalian University of Technology, Xi'an Jiaotong University and Beijing University of Aeronautics and Astronautics have carried out related research work on supersonic cyclone separation technology, and the representative structures are ZL200810011258.6, ZL200910023458. 8 and application numbers 200910024347.9, 200910081813.7, 200910093744.1, 201010597341.3, etc.

The supersonic cyclone separator has a good technical application in natural gas dehydration and heavy hydrocarbon removal, but it also has certain defects, such as a relatively complex structure and difficulty in processing. After condensation, water and heavy components are prone to secondary evaporation, which significantly reduces the removal efficiency of water and heavy components.

Contents of the invention

In order to solve the problems existing in the prior art, the present invention proposes a gradually expanding and swirling supersonic nozzle for natural gas treatment with simple structure and stable operation. The specific technical scheme adopted is as follows:

The present invention proposes a gradually expanding swirl type supersonic nozzle, which mainly includes a nozzle inlet, a nozzle tapering section, a nozzle throat, a nozzle expanding section, a nozzle outlet, and a swirling flow located in the nozzle expanding section. device etc.

The convergent section of the above-mentioned nozzle is designed by the bicubic curve method. This method makes the flow field excessively natural, the vortex is small, and a uniform airflow can be obtained at the exit of the contraction section. The curve equation satisfies:

In the above equation, x is the axial distance of the nozzle; r _cr is the radius of the throat section of the nozzle; r is the section radius at any axial distance x of the nozzle; L is the length of the _tapered section of the nozzle; The relative coordinates of the connection points of the segment curves.

The selection of the diameter of the throat of the above-mentioned nozzle is limited by the air flow rate. The diameter of the throat of the nozzle is calculated using the BWRS equation of the real gas state. The smooth transition of the divergent section of the pipe.

The diverging section of the above-mentioned nozzle adopts a tapered tube design, and the expansion angle is 1 to 10 degrees to ensure uniform air flow through the cyclone.

The cyclone is composed of 2 to 8 fan-shaped blades with the same structure. This structure can make the gas generate high-speed swirl, and the huge centrifugal force generated by the swirl will throw the liquid droplets to the wall of the supersonic nozzle.

The natural gas containing water vapor and heavy hydrocarbon components enters the supersonic nozzle through the gas inlet, expands and accelerates, and accelerates to supersonic speed after passing through the throat. Under the low temperature and low pressure environment in the nozzle, the water vapor and heavy hydrocarbon components in it condense into liquid droplets , and then flow through the cyclone in the expanding section of the nozzle to achieve high-speed swirl under supersonic conditions, and the huge centrifugal force generated by the swirl will throw the droplets to the wall of the supersonic nozzle, where they will be separated or absorbed in the subsequent process, thus realizing Removal of water and heavy hydrocarbon components in natural gas.

The beneficial effects of the natural gas supersonic cyclone separation system provided by the present invention are: compared with complex supersonic cyclone separators, the processing is very convenient, and it is easy to realize the condensation and cyclone separation of water and heavy hydrocarbons, while avoiding the shock wave effect and condensate The secondary evaporation phenomenon of droplets can replace the traditional supersonic separator to realize complex processes such as dehydration of natural gas and removal of heavy hydrocarbons.

Description of drawings

Figure 1: A schematic diagram of the overall structure of a gradually expanding swirling supersonic nozzle proposed by the present invention.

Fig. 2: A schematic diagram of the nozzle line used in a progressively expanding swirl supersonic nozzle proposed by the present invention.

Figure 3: Schematic diagram of the overall structure of the swirler used in a gradually expanding swirling supersonic nozzle proposed by the present invention.

Fig. 4: A side view of a swirler used in a gradually expanding swirling supersonic nozzle proposed by the present invention.

1-Nozzle inlet, 2-Nozzle tapering section, 3-Nozzle throat, 4-Nozzle diverging section, 5-Nozzle outlet, 6-Swirl.

detailed description

Now in conjunction with accompanying drawing, the present invention is further described:

As shown in Fig. 1-2, the tapered supersonic nozzle proposed by the present invention includes nozzle inlet (1), nozzle tapering section (2), nozzle throat (3), nozzle expanding section (4) , nozzle outlet (5), cyclone (6), etc.

Natural gas containing water vapor and heavy hydrocarbon components enters the supersonic nozzle from the nozzle inlet (1) and continuously expands and cools down, and expands to supersonic speed after passing through the nozzle throat (3). Water vapor and heavy hydrocarbon components condense into liquid droplets, and then pass through the expanding section (4) of the nozzle. Under the action of the cyclone (6), a high-speed swirling flow is realized under supersonic conditions, and the huge centrifugal force generated by the swirling flow drives the liquid Drops are thrown to the wall of the supersonic nozzle, and are separated or absorbed in the subsequent process, so as to achieve the purpose of natural gas dehydration and heavy hydrocarbon removal.

Claims (5)

1. A gradually expanding swirl type supersonic nozzle, comprising a nozzle inlet (1), a nozzle tapering section (2), a nozzle throat (3), a nozzle expanding section (4), and a nozzle outlet (5), cyclone (6), etc., the above-mentioned six parts are connected coaxially in sequence; pipe throat (3). 2. A kind of gradually expanding swirl type supersonic nozzle according to claim 1, characterized in that: said swirler (6) is located in the nozzle diverging section (4), and the nozzle diverging section (4) The inner wall surface is closely matched to generate swirl acceleration under supersonic conditions. 3. A gradually expanding swirl supersonic nozzle according to claim 1, characterized in that: said swirler (6) is composed of 2 to 8 fan-shaped blades with the same structure. 4. A kind of gradually expanding swirl type supersonic nozzle according to claim 1, it is characterized in that: the diameter of described nozzle throat (3) adopts the real gas state BWRS equation to calculate, and the throat curve selects a section of circle The arc serves as the transition between the nozzle convergent (2) and nozzle divergent (4). 5. A gradually expanding swirling supersonic nozzle according to claim 1, characterized in that: the expanding section (4) of the nozzle is designed with a conical tube, and the expansion angle is 1 to 10 degrees to ensure that the flow through the swirling The airflow is uniform.