Wellhead high-pressure natural gas desulfurization device
Technical Field
The utility model belongs to desorption hydrogen sulfide technology, concretely relates to well head high pressure natural gas desulphurization unit.
Background
China contains sulfur (mainly H)2S) the natural gas yield of the gas field accounts for more than 60% of the whole country, and the sulfur recovered from the sulfur-containing natural gas accounts for about 30% of the sulfur yield of China. At present, the process for intensively treating domestic sulfur-containing natural gas is mature, and the design treatment scale is usually 100x104m3Over hundred million equipment investment, wet desulphurization by adopting MDEA, alcohol amine method, sulfone amine method and the like, and then recovering Claus sulfur; for single wells with developed construction, more villages and towns, densely developed population, highways and railways in the periphery, the problems of large occupied area, difficulty in removal and the like exist in site station building and processing, and certain hidden danger and difficulty exist in terms of safety, removal and the like if a centralized purification processing mode of a desulfurization plant is adopted; the content of sulfide is not too low, but the working condition of Claus sulfur recovery is not suitable, and the natural gas can not be desulfurized on site for use; in addition, the treatment of natural gas with very low sulphide content is mature, solid iron oxide processes can be used, and it is not yet possible to desulphurise natural gas on site for its use in some sites and their surroundings in remote areas; in addition, large-scale equipment cannot be built on site in deserts, gobi, oceans and the like, and the natural gas found cannot be desulfurized and recycled. Therefore, this portion of gas wells has been around for many yearsThe method can not be put into development, and the recovery of exploration and drilling cost is seriously influenced.
In order to overcome the disadvantages of the prior art and the disadvantages of the traditional natural gas desulfurization and purification process, the complex iron natural gas desulfurization technology directly converts sulfides in the natural gas into elemental sulfur while desulfurizing, thereby simplifying the process flow, facilitating the operation, reducing the investment and being suitable for in-situ desulfurization and purification of the natural gas at the well head. The sulfur paste generated by the complex iron desulfurization technology needs further sulfur refining, a boiler is needed by adopting the traditional steam sulfur melting, and the construction of a boiler system is not practical in remote places, deserts and other places; the oxidation regeneration and the sulfur concentration of the traditional complex iron desulfurization technology are carried out in one oxidation regeneration tank, and for the working condition with higher latent sulfur content, the size of the oxidation regeneration tank is very large and needs to be built on site, which brings great difficulty for remote places. The natural gas contains organic sulfur such as mercaptan and the like, and is converted into disulfide, sulfone or sulfoxide after being absorbed, and the regenerated waste air carries a small amount of organic sulfur such as disulfide and the like, so that the odor is great, and the influence on the working environment is great.
Disclosure of Invention
The utility model adopts the gas sulfur melting equipment, uses low-pressure flash evaporation gas as fuel to melt sulfur, and the clear liquid after sulfur melting can be used as filtering washing water, thus saving the public works;
the utility model discloses it is big still to result in the equipment size to subside in a container regeneration and sulphur to traditional complex iron desulfurization technique, is difficult to engineering skid-mounted ization, the utility model discloses the regeneration function and the sulphur that subsides the rich liquid of doctor solution subsides the function and parts, makes things convenient for skid-mounted ization design.
In order to realize the purpose, the utility model relates to a wellhead high-pressure natural gas desulfurization device, which comprises an absorption tank, a purified gas-liquid separation tank, a raw material gas-liquid separation tank, a flash tank, an oxidation regeneration tank, a sulfur settling tank, a sulfur slurry filter and a sulfur melting kettle;
a first gas inlet of the feed gas-liquid separation tank is connected with the sulfur-containing natural gas through a first pipeline, and a first gas outlet of the feed gas-liquid separation tank is communicated with the absorption tank through a second pipeline; a liquid inlet of the absorption tank is communicated with the sulfur settling tank through a third pipeline, a first liquid outlet of the absorption tank is communicated with the flash tank through a fourth pipeline, and a second gas outlet of the absorption tank is communicated with the purified gas-liquid separation tank through an eleventh pipeline; the second liquid outlet of the flash tank is communicated with the rich liquid inlet of the oxidation regeneration tank through a fifth pipeline, and the third gas outlet of the flash tank is communicated with the sulfur melting kettle through a twelfth pipeline; the overflow liquid outlet of the oxidation regeneration tank is communicated with a sulfur settling tank through a sixth pipeline, and the slurry outlet of the sulfur settling tank is communicated with a sulfur slurry filter through a seventh pipeline; and a sulfur paste outlet of the sulfur slurry filter is communicated with the sulfur melting kettle through an eighth pipeline.
Further, the device also comprises an exhaust gas purification tower, a filtrate tank and a clear liquid tank; a fourth gas outlet of the oxidation regeneration tank is communicated with a waste gas purification tower through a ninth pipeline, a filtrate outlet of the sulfur slurry filter is communicated with a filtrate tank through a thirteenth pipeline, and an outlet of the clear liquid tank is communicated with a flushing inlet of the sulfur slurry filter through a fourteenth pipeline; a fifth gas outlet of the sulfur melting kettle is communicated with the waste gas purification tower through a tenth pipeline, and a clear liquid outlet of the sulfur melting kettle is communicated with an inlet of the clear liquid tank through a fifteenth pipeline; and a filtrate outlet of the filtrate tank is communicated with the oxidation regeneration tank through a sixteenth pipeline.
Furthermore, the oxidation regeneration tank is sequentially divided into a first descending area of the oxidation regeneration tank, a first regeneration area of the oxidation regeneration tank, a second descending area of the oxidation regeneration tank and a second regeneration area of the oxidation regeneration tank by a first partition plate of the oxidation regeneration tank, a second partition plate of the oxidation regeneration tank and a third partition plate of the oxidation regeneration tank, and the second regeneration area of the oxidation regeneration tank is sequentially connected and communicated with the first descending area of the oxidation regeneration tank by a seventeenth pipeline, a circulating pump, a solution heat exchanger and an eighteenth pipeline; a sulfur settling tank partition plate is arranged in the sulfur settling tank to divide the sulfur settling tank into a descending area and a barren liquor area; the sulfur melting kettle comprises a sulfur melting kettle body and a gas burner, and a third gas outlet of the flash tank is communicated with the gas burner through a twelfth pipeline.
Further, a liquid inlet of the absorption tank is communicated with the sulfur settling tank through a third pipeline, a barren solution pump and a barren solution pump inlet pipeline in sequence; and the slurry outlet of the sulfur settling tank is communicated with the sulfur slurry filter sequentially through a seventh pipeline, a sulfur slurry pump and a filtering pipeline.
Further, an outlet of the clear liquid groove is communicated with a flushing inlet of the sulfur slurry filter sequentially through a clear liquid pump inlet pipeline, a clear liquid pump and a fourteenth pipeline; a clear liquid outlet of the sulfur melting kettle is communicated with an inlet of the clear liquid tank through a fifteenth pipeline and a clear liquid cooler in sequence; and a filtrate outlet of the filtrate tank is communicated with the oxidation regeneration tank through a sixteenth pipeline, a filtrate pump and a filtrate return oxidation regeneration tank pipeline in sequence.
Furthermore, a purified natural gas pipeline is arranged on one path of a sixth gas outlet of the purified gas-liquid separation tank, and the other path of the sixth gas outlet of the purified gas-liquid separation tank is communicated with a sulfur melting kettle burner through a pipeline.
Further, a pressure control valve is arranged on the fourth pipeline.
Further, the air distributor at the bottom of the oxidation regeneration tank is connected with an air blower through an air inlet pipeline.
Further, the absorption tank and the purified gas-liquid separation tank are concentrically arranged from top to bottom, the purified gas-liquid separation tank is arranged above the absorption tank, and the outlet of the purified gas-liquid separation tank is concentrically connected with the absorption tank through a pipeline and extends to the position below the liquid level of the solution.
Compared with the prior art, the utility model has the advantages of it is following:
1. the utility model discloses rich liquid oxidation regeneration and sulphur subside the concentration and part, but skid-mounted ization design on the engineering, can realize single well desulfurization on the spot and retrieve valuable natural gas resource in desert, gobi and remote area gas well that are not suitable for the field construction.
2. The sulfur melting efficiency is improved by adopting the fuel gas to melt sulfur, large-scale public works are saved, and the remote high-pressure high-sulfur natural gas complex iron desulfurization is facilitated.
3. The utility model discloses to complex iron desulfurization technique in the natural gas desulfurization, the condition that regeneration waste air produced foul gas adopts activated carbon adsorption to carry out purification treatment to waste gas, and desulphurization unit does not have the three wastes and discharges.
Drawings
FIG. 1 is a schematic view of the flow of the wellhead high-pressure natural gas desulfurization device of the utility model.
Detailed Description
The present invention will be described in further detail with reference to the following drawings and specific embodiments.
As shown in figure 1, the wellhead high-pressure natural gas desulfurization device comprises an absorption tank 12, a purified gas-liquid separation tank 13 with a demister assembly 28, a raw material gas-liquid separation tank 11 with an oil skimming filter assembly 26, a flash tank 14, an oxidation regeneration tank 15, a sulfur settling tank 16, a sulfur slurry filter 17, a sulfur melting kettle 18, a waste gas purification tower 19, a filtrate tank 20 and a clear liquid tank 21 which are concentrically arranged up and down, wherein the purified gas-liquid separation tank 13 is arranged above the absorption tank 12, and the lower outlet of the purified gas-liquid separation tank 13 is concentrically connected with the absorption tank through a pipeline and extends to the position below the liquid level of a solution. Wherein, the oxidation regeneration tank 15 is sequentially divided into an oxidation regeneration tank first descending area 15A, an oxidation regeneration tank first regeneration area 15B, an oxidation regeneration tank second descending area 15C and an oxidation regeneration tank second regeneration area 15D by an oxidation regeneration tank first clapboard 22, an oxidation regeneration tank second clapboard 23 and an oxidation regeneration tank third clapboard 24, and the oxidation regeneration tank second regeneration area 15D is communicated with the oxidation regeneration tank first descending area 15A through a seventeenth pipeline 1117, a circulating pump 151, a solution heat exchanger 152 and an eighteenth pipeline 1511 in sequence; a sulfur settling tank partition plate 25 is arranged in the sulfur settling tank 16 to divide the sulfur settling tank 16 into a descending area 16A and a barren liquor area 16B; the sulfur melting kettle 18 comprises a sulfur melting kettle body 18A and a gas burner 18B.
A first gas inlet 11a of the feed gas-liquid separation tank 11 is connected with the high-pressure sulfur-containing natural gas which is heated and throttled through a first pipeline 1101, and a first gas outlet 11b of the feed gas-liquid separation tank 11 is communicated with the absorption tank 12 through a second pipeline 1102; a liquid inlet 12a of the absorption tank 12 is communicated with the sulfur settling tank 16 sequentially through a third pipeline 1103, a barren liquor pump 153 and a barren liquor pump inlet pipeline 1531, a first liquid outlet 12b of the absorption tank 12 is communicated with the flash tank 14 through a fourth pipeline 1104, and a second gas outlet 12c of the absorption tank 12 is communicated with the purified gas-liquid separation tank 13 through an eleventh pipeline 1111; a second liquid outlet 14a of the flash tank 14 is communicated with a rich liquid inlet of the oxidation regeneration tank 15 through a fifth pipeline 1105, a third gas outlet 14B of the flash tank 14 is communicated with a gas burner 18B through a twelfth pipeline 1112, and a pressure control valve 27 is arranged on a fourth pipeline 1104; an overflow liquid outlet 15a of the oxidation regeneration tank 15 is communicated with a sulfur settling tank 16 through a sixth pipeline 1106, a fourth gas outlet 15b of the oxidation regeneration tank 15 is communicated with a waste gas purification tower 19 through a ninth pipeline 1109, and meanwhile, an air distributor at the bottom of the oxidation regeneration tank 15 is connected with an air blower 158 through an air inlet pipeline 1581; the slurry outlet 16a of the sulfur settling tank 16 is communicated with the sulfur slurry filter 17 through a seventh pipeline 1107, a sulfur slurry pump 154 and a filtering pipeline 1541 in sequence; a sulfur paste outlet 17a of the sulfur slurry filter 17 is communicated with the sulfur melting kettle 18 through an eighth pipeline 1108, a filtrate outlet 17b of the sulfur slurry filter 17 is communicated with the filtrate tank 20 through a thirteenth pipeline 1113, and an outlet of the clear liquid tank 21 is communicated with a flushing inlet 17c of the sulfur slurry filter 17 through a clear liquid pump inlet pipeline 1561, a clear liquid pump 156 and a fourteenth pipeline 1114 in sequence; a fifth gas outlet 18a of the sulfur melting kettle 18 is communicated with the waste gas purification tower 19 through a tenth pipeline 1110, and a clear liquid outlet 18b of the sulfur melting kettle 18 is communicated with an inlet of the clear liquid tank 21 through a fifteenth pipeline 1115 and the clear liquid cooler 157 in sequence; the filtrate outlet 20a of the filtrate tank 20 is connected and communicated with the oxidation regeneration tank 15 through a sixteenth pipeline 1116, a filtrate pump 155 and a filtrate return oxidation regeneration tank pipeline 1551 in sequence.
In addition, a purified natural gas pipeline 1311 is arranged on one path of a sixth gas outlet 13a of the purified gas-liquid separation tank 13, and the other path of the sixth gas outlet 13a of the purified gas-liquid separation tank 13 is communicated with a gas burner 18B through a pipeline 1312; the seventh gas outlet 19a of the waste gas purification tower 19 is provided with a waste air emptying pipe 1911, and the sulfur melting kettle body 18A is provided with a liquid sulfur outlet pipe 1811.
In this embodiment, the second gas outlet 12c of the absorption tank 12 is disposed above the side surface of the cylinder of the absorption tank 12, and is connected to and communicated with the side surface of the purified gas-liquid separation tank 13 through an eleventh pipe 1111; the gas phase inlet 13b of the purified gas-liquid separation tank 13 is arranged on the cylinder side below the demister assembly 28; the upper end of the absorption tank 12 is an elliptical seal head, the middle is a cylinder body, the lower end is a cone body, a plurality of gas distributors 29 are arranged at the joints of the cylinder body and the cone body, and the gas distributors 29 are communicated with a raw material gas inlet pipeline 1102.
A sulfur settling tank partition plate 25 is arranged in the sulfur settling tank 16 to divide the sulfur settling tank 16 into a descending area 16A and a barren liquor area 16B, a liquid-solid mixture enters the descending area 16A and passes through a channel below the sulfur settling tank partition plate 25 from the bottom of the descending area 16A to enter the barren liquor area 16B, the lower end of the sulfur settling tank 16 is a cone part for settling and concentrating sulfur, a barren liquor outlet is formed in the upper part of the side of the barren liquor area 16B and is communicated with a barren liquor pump, and the barren liquor pump is communicated with the absorption tank 12 through a third pipeline.
An extraction outlet is arranged below an overflow liquid outlet 15a of the oxidation regeneration tank 15, an inlet of a circulating pump is communicated with the extraction outlet, a solid-liquid mixture is extracted by the circulating pump, the material subjected to heat exchange by a solution heat exchanger is pumped into a pipeline of a rich liquid inlet of the oxidation regeneration tank, the material is mixed with rich liquid from a flash tank and then enters the oxidation regeneration tank, and the heat exchanger is used for maintaining the temperature of the system at 48-55 ℃.
The sulfur melting kettle 18 is heated by burning fuel gas, the sulfur melting kettle consists of a sulfur melting kettle body and a fuel gas burner, and the flue gas is communicated with a waste gas purification tower through a ninth pipeline from a flue gas outlet at the upper end of the sulfur melting kettle; a clear liquid outlet 18b in the sulfur melting kettle 18 is connected with the clear liquid cooler 157 through a fifteenth pipeline 1115, clear liquid after temperature reduction is collected in the clear liquid tank 21, and the clear liquid pump 156 pumps liquid from an inlet pipeline 1561 of the clear liquid pump of the clear liquid tank 21 for filtering and flushing; the liquid sulfur flows out from the middle part of the side surface, and is stacked and transported outside after being formed.
The pressure of the natural gas containing hydrogen sulfide entering the desulfurizing device is 1.0MPa-7.0 MPa.
The desulfurizer is a complex solution containing ferric iron; the adsorbent filled in the waste gas purification tower is granular activated carbon.
The utility model discloses well head high pressure natural gas desulphurization unit implementation specifically includes following step:
1) hydrogen sulfide absorption
High-pressure natural gas containing hydrogen sulfide from a wellhead is heated and throttled and then conveyed to a first gas inlet 11a of a raw material gas-liquid separation tank 11 through a first pipeline 1101, free liquid is separated after the high-pressure natural gas containing hydrogen sulfide passes through an oil skimming filtering assembly 26 in the raw material gas-liquid separation tank 11, the natural gas containing hydrogen sulfide enters an absorption tank 12 from a first gas outlet 11B of the raw material gas-liquid separation tank 11 through a second pipeline 1102 and then is divided into multi-path bubbling absorption, lean liquid in a lean liquid area 16B of a sulfur settling tank 16 is conveyed to the absorption tank 12 through a third pipeline 1103 through a lean liquid pump 153, H in the natural gas2S enters a liquid phase and is oxidized into sulfur by iron ions in the poor liquid of the desulfurizer, the desulfurized liquid containing the sulfur is rich liquid, and the desulfurized natural gas enters the purified gas-liquid separation tank 13 through the eleventh pipeline 1111 to remove free liquid and entrained sulfur particles and then enters the post-process from the sixth gas outlet 13a of the purified gas-liquid separation tank 13.
2) Solution oxidation regeneration
The rich liquid containing sulfur is discharged from a first liquid outlet 12b at the bottom of the absorption tank 12 and enters the flash tank 14 through a fourth pipeline 1104, the natural gas dissolved in the rich liquid is decompressed and controlled by a pressure control valve 27 to be desorbed and flow out from a third gas outlet 14b of the flash tank 14, the natural gas dissolved in the rich liquid enters the oxidation regeneration tank 15 from a second liquid outlet 14a at the bottom of the flash tank 14 through a fifth pipeline 1105, the rich liquid containing sulfur contacts with the regeneration air bubbling from the air blower 158 in the oxidation regeneration tank 15, the complex ferrous iron is oxidized into complex iron by oxygen, meanwhile, sulfur particles grow up, and the regeneration waste air enters the waste gas purification tower 19 from a fourth gas outlet 15b at the upper end of the oxidation regeneration tank 15 through a ninth pipeline 1109.
3) Sulphur slurry filtration
The regenerated solid-liquid mixture enters the sulfur settling tank 16 from an overflow liquid outlet 15a of the oxidation regeneration tank 15 through a sixth pipeline 1106, sulfur is settled to the bottom for concentration under the action of gravity, the sulfur slurry is pumped out from a slurry outlet 16a of the sulfur settling tank 16 through a sulfur slurry pump 154 and is pumped into the sulfur slurry filter 17 through a seventh pipeline 1107, the filtrate enters the filtrate tank 20 through a thirteenth pipeline 1113, the filtrate is pumped back to the oxidation regeneration tank 15 from a filtrate outlet 20a of the filtrate tank 20 through a filtrate pump 155, and the filtered solid is sulfur paste.
4) Refining of sulphur
The filtered sulfur paste enters the sulfur melting kettle 18 through an eighth pipeline 1108, liquid sulfur in the sulfur melting process is used as product sulfur, clear liquid generated in the sulfur melting process enters a clear liquid tank 21 after being cooled by a clear liquid cooler 157, and the clear liquid is sent to the sulfur slurry filter 17 through a clear liquid pump 156 to be used as washing water.
5) Exhaust gas purification
The fourth gas outlet 15b of the oxidation regeneration tank 15 enters the waste gas purification tower 19 through a ninth pipeline 1109, the flue gas in the sulfur melting kettle 18 enters the waste gas purification tower 19 through a tenth pipeline 1110, and the waste gas is discharged at high altitude after passing through the purification tower.