KR102299160B1 - Wastewater treatment system for FPSO - Google Patents

Abstract

The wastewater treatment system 10 is a liquid receiver 26 provided below at least one of the first devices 13 , a temporary storage tank 47 connected to the liquid receiver via a conduit to temporarily store the liquid collected therein. a temporary storage tank 47 for storing the It has a contaminated water storage tank 58 connected to the temporary storage tank via a conduit with two valves 57 .

Description

Wastewater treatment system for FPSO

The present invention relates to a wastewater treatment system for FPSO.

Vessels are known having a collecting header for collecting liquid containing rainwater that falls on the deck and an outlet formed in the outer plate of the hull for discharging the liquid collected in said collecting header to the sea (cf. e.g. For example, Japanese Unexamined Patent Application Publication No. 7-117787).

In Floating Production, Storage and Off-loading systems (LNG-FPSOs), chemicals such as amines and monoethylene glycol are often used in the mining and refining of natural gas. Therefore, when rainwater is discharged to the outside of the vessel as it is, when the chemical is leaked, the chemical is discharged out of the vessel together with the rainwater, thereby contaminating the sea. On the other hand, all rainwater falling on the FPSO can be stored as polluted water in a tank, and the stored polluted water can be periodically unloaded to another vessel. In this case, a large tank is needed to store the contaminated water, and the space of the FPSO is narrowed. Also, due to rainfall, it is necessary to frequently unload contaminated water to other vessels.

The present invention was made in view of this background, and a main object of the present invention is to provide a wastewater treatment system for FPSO capable of discharging rainwater to the sea while preventing the discharge of polluted water.

To achieve this object, one aspect of the present invention provides a wastewater treatment system (10) for an FPSO (1) comprising a chemical plant (5), said chemical plant comprising a plurality of first devices (13). wherein the wastewater treatment system (10) comprises: a liquid receiver (26) provided below at least one of the first devices, the liquid containing rainwater and chemicals that may have leaked from the first devices. a liquid receiver 26 for receiving; a temporary storage tank (47) connected to the liquid container through a conduit, the temporary storage tank (47) temporarily storing the liquid collected in the liquid container; a discharge conduit (52) connected to the temporary storage tank and having a first valve (55), the discharge conduit (52) for discharging liquid stored in the temporary storage tank into the sea; and a contaminated water storage tank 58 connected to the temporary storage tank through a conduit having a second valve 57 .

According to this aspect of the invention, a wastewater treatment system may temporarily store liquids, including rainwater and chemical spills, in temporary storage tanks. The liquid stored in the temporary storage tank may be chosen to be discharged to the sea or stored in a contaminated water storage tank, depending on the quality of the liquid. Therefore, when the chemical is not contained in the liquid or the concentration of the chemical is lower than the regulation value, the amount of liquid stored in the contaminated water storage tank can be reduced by discharging the liquid to the sea.

The wastewater treatment system includes an oil-water separator 35 provided between a liquid receiver and a temporary storage tank, the oil-water separator 35 separating oil from the liquid collected in the liquid receiver; and a waste oil storage tank 85 connected to the oil-water separator through a conduit, and a waste oil storage tank 85 for storing the oil separated by the oil-water separator.

According to this aspect of the invention, oil may be removed from the liquid by an oil-water separator. Therefore, even when the oil is mixed with the liquid, after removing the oil from the liquid, the liquid can be discharged into the sea.

The wastewater treatment system may further include a detector 61 for detecting chemicals in the liquid stored in the temporary storage tank.

According to this aspect of the invention, the concentration of the chemical in the liquid can be detected by the detector. Thus, it is easy to choose whether to discharge the liquid to the sea or to store the liquid in a contaminated water storage tank.

The wastewater treatment system may further include a control device 63 for controlling the first valve and the second valve based on the concentration of the chemical in the liquid detected by the detector.

According to this aspect of the invention, the control device automatically selects whether to discharge the liquid to the sea or to store the liquid in a polluted water storage tank according to the concentration of the chemical in the liquid.

The FPSO may comprise a hull 2 and a plurality of floors 11 , 12 arranged vertically on the hull; wherein the plurality of floors comprises a collecting floor (11) and at least one upper floor (12) provided above the collecting floor; The collection bottom has a gutter 21 that collects the liquid flowing on the surface of the collection floor and is connected via a conduit to a temporary storage tank, each upper bottom 12 having several grating floors. (28), the liquid receiver is provided on the collecting bottom and the upper bottom. In another aspect, the FPSO may comprise a hull (2) and a collection bottom (11) provided on said hull; The collection bottom has a ditch 21 that collects the liquid flowing on the surface of the collection bottom and is connected to a temporary storage tank via a conduit, and a liquid receiver is provided on the collection bottom.

According to this aspect of the invention, rainwater falling on the module is collected at the collecting floor and delivered to a temporary storage tank. Thus, after detecting the presence of a chemical, it is possible to choose whether to discharge the liquid to the sea or to transfer it to a polluted water storage tank.

An oil-water separator may be provided on the hull deck.

According to this aspect of the invention, the liquid on the module can flow to the oil-water separator by gravity.

A temporary storage tank may be provided in the upper part of the hull, and a contaminated water storage tank may be provided in the hull below the temporary storage tank.

According to this aspect of the invention, the liquid may flow from the oil-water separator to the temporary storage tank by gravity. Also, the liquid may flow from the temporary storage tank to the contaminated water storage tank by gravity. Also, liquids can flow from temporary storage tanks into the sea by gravity.

The first apparatus may include an acid degassing apparatus that uses an amine to adsorb the acid gas. The first apparatus may include an inhibitor of hydrate formation regenerator for treating monoethylene glycol.

According to this aspect of the invention, certain chemicals can be prevented from being discharged into the sea.

The wastewater treatment system for the FPSO is a second liquid receiver 26 provided below at least one of the second devices 14 , containing a liquid containing rainwater and oil that may have leaked from the second device. liquid receiver 26; a second oil-water separator (94) connected to a second liquid receiver via a conduit, comprising: a second oil-water separator (94) for separating oil from the liquid collected in the second liquid receiver; And as a second discharge conduit 104 connected to the second oil-water separator, the second discharge conduit 104 for discharging water separated from oil by the second oil-water separator to the sea; may further include, the second oil-water The separator is connected to the waste oil storage tank through a conduit that delivers the oil separated by the second oil-water separator to the waste oil storage tank.

According to this aspect of the present invention, it is possible to separate the oil leaking from the second device from the rainwater and store only the oil in the waste oil storage tank.

1 is a schematic diagram of an FPSO.
2 is a perspective view of the module;
3 is a block diagram of a wastewater treatment system.
4 is a block diagram of a wastewater treatment system.

Preferred embodiments of the present invention are described below with reference to the accompanying drawings.

As shown in FIG. 1 , the LNG-FPSO 1 , also called FLNG, is an offshore facility that refines natural gas, liquefies natural gas, stores LNG, and unloads LNG. The FPSO (1) has a hull (2) floating in the sea. A production facility 4 is provided on the deck 3 of the hull 2 for producing LNG. The production plant 4 comprises a plurality of modules 5 , 6 . The hull 2 is provided with a plurality of LNG tanks 7 for storing the LNG produced by the production facility 4 . At the rear end of the deck 3, a residential facility 8 in which workers can reside is provided. The FPSO 1 also has a wastewater treatment system 10 for treating wastewater such as rainwater and leaky liquids generated from the plurality of modules 5 and 6 .

Each module 5 , 6 has a plurality of vertically arranged floors 11 , 12 . Some of the plurality of modules 5 , 6 are chemical modules 5 comprising at least one first device 13 using chemicals. Also, some of the plurality of modules 5 , 6 are oil modules 6 comprising at least one second device 14 using an oil, such as a fuel or lubricating oil.

The first apparatus 13 may comprise acid gas removal means and a hydrate formation inhibitor regenerator. The acid gas removal means removes acid gases such as carbon dioxide and hydrogen sulfide from the feed gas using an absorption liquid. The absorption liquid contains an amine such as monoethanolamine or N-methyl diethanolamine. The acid gas removal means has an absorption tower for contacting the feed gas and the absorption liquid with each other and a regeneration tower for regenerating the absorption liquid containing the acid gas. The hydrate formation inhibitor regenerator regenerates the hydrate formation inhibitor that is injected into the pipeline connecting the FPSO 1 and the natural gas well. Hydrate formation inhibitors contain, for example, monoethylene glycol. The hydrate formation inhibitor regenerator may also have a centrifuge to separate the solid impurities from the hydrate formation inhibitor.

The second device 14 may comprise an oil-fueled boiler or an internal combustion engine, such as a turbine or reciprocating engine. The second device 14 may also include a compressor and generator using oil for lubrication.

1 and 2 , one of the plurality of floors 11 , 12 of each chemical module 5 is a collecting floor 11 for collecting a liquid such as rainwater. . The collection floor 11 may be the lowest floor within the chemical module 5 . At least one upper floor 12 is provided above the collection floor 11 . All bottoms disposed above the collection bottoms 11 are the upper bottom 12 .

The collecting bottom 11 is formed of a plate material such as an iron plate so as not to allow the liquid to pass therethrough. A downwardly concave gutter 21 is formed on the collecting bottom 11 . The trench 21 may be arranged to surround the collection bottom 11 . In another embodiment, the trench 21 may be arranged to cross the collection floor 11 . The collection bottom 11 may be inclined towards the trench 21 . A drain box 22 concave downwards is formed in a suitable location on the collection bottom 11 . The upper opening of the ditch 21 and the discharge box 22 are closed by several gratings 23 . The conduit 24 is connected to the bottom of the ditch 21 and the discharge box 22 . The bottom portion of the gutter 21 is inclined towards the connection with the conduit 24 .

Each upper floor 12 has several grating floors 28 through which liquid can pass downwards. At suitable positions of the collecting bottom 11 and the upper bottom 12, a plurality of upwardly open dish-shaped drip pans 26 (liquid receivers) are provided. Each of the first devices 13 is arranged above the drip pan 26 .

Each drip pan 26 on the collection bottom 11 and upper bottom 12 is connected with a conduit 24 via a conduit 31 . Conduits 31 are connected such that liquid flows from each drip pan 26 to conduits 24 by gravity.

The oil module 6 has the same structure as the chemical module 5 . The oil module 6 has one collecting bottom 11 and at least one upper bottom 12 . The collecting bottom 11 of the oil module 6 has a ditch 21 , a drip pan 26 , a discharge box 22 , each upper bottom 12 having a grid bottom 28 and a drip pan (26). The conduit 32 is connected to the ditch 21 and the drain box 22 of the oil module 6 . Each drip pan 26 of the oil module 6 is connected to the middle portion of the conduit 32 via a conduit 33 .

3 and 4 show block diagrams of a wastewater treatment system 10 . 3 and 4, the letters A and B are connected to each other by corresponding letters. One end of the conduit 24 extending from the chemical module 5 is connected with a first collecting pit 35 (oil-water separator). The first collection pit 35 has a first chamber 37 and a second chamber 38 defined by a vertically extending septum 36 . A connection passage 39 connecting the first chamber 37 and the second chamber 38 is formed in a lower portion of the partition wall 36 . The conduit 24 is connected to the first chamber 37 . An upper portion of the second chamber 38 is provided with a first outlet 41 , and a lower portion of the second chamber 38 is provided with a second outlet 42 . An upper portion of the first chamber 37 is provided with a third outlet 43 , and a lower portion of the first chamber 37 is provided with a fourth outlet 44 . When the liquid stored in the first collection pit 35 exceeds a certain amount, the liquid overflows from the first outlet 41 and the third outlet 43 . Since oil is lighter than water, the oil contained in the liquid supplied from the conduit 24 to the first collection pit 35 collects near the liquid surface of the first chamber 37 . Accordingly, the liquid containing little oil (water) flows outward from the first outlet 41 , and the liquid containing much oil flows outward from the third outlet 43 . The first collection pit 35 functions as an oil-water separator.

The first outlet 41 is connected to the temporary storage tank 47 via a conduit 46 . The second outlet 42 is connected to the conduit 46 via a conduit 49 with a manual valve 48 .

The temporary storage tank 47 is a tank for temporarily storing a liquid. The outlet of the temporary storage tank 47 is connected with the suction port of the pump 51 . A first discharge conduit 52 and a conduit 53 branched from each other are connected to the discharge port of the pump 51 . The first exhaust conduit 52 is provided with a first control valve 55 . At the downstream end of the first discharge conduit 52 , a first discharge outlet 56 is provided for discharging the liquid into the sea. The conduit 53 is provided with a second control valve 57 , the conduit 53 is connected to the contaminated water storage tank 58 . The contaminated water storage tank 58 is a tank for storing liquid containing chemicals. Chemicals may include amines and monoethylene glycol.

The temporary storage tank 47 or conduit 46 is provided with a chemical detection device 61 for detecting chemicals in the liquid. The chemical detection device 61 may include a pH meter and an electrical conductivity meter. The temporary storage tank 47 is provided with a liquid level gauge 62 for detecting the liquid level in the temporary storage tank 47 . The chemical detection device 61 and the liquid level gauge 62 are connected to the control device 63 . The control device 63 is connected to the pump 51 , the first control valve 55 and the second control valve 57 . The control device 63 makes a decision based on the signals from the chemical detection device 61 and the liquid level gauge 62, and the pump 51, the first control valve 55 and the second control unit according to the determination result. Control the valve (57).

The contaminated water storage tank 58 is connected to the chemical discharge drum 66 via a conduit 65 . The chemical discharge drum 66 is connected with a plurality of first devices 13 , and the chemical stock is discharged from the first device 13 . The conduit 65 is provided with a valve 67 . If the drained liquid in the chemical discharge drum 66 degrades, when the valve 67 is opened, the chemical stock stored in the chemical discharge drum 66 is passed through the conduit 65 Contaminated water is transferred to a storage tank (58).

The first unloading pipe 68 is connected to the contaminated water storage tank 58 . The first unloading pipe 68 is provided with a pump 69 . The first unloading pipe 68 may be connected to a receiving port of a waste liquid carrier, and may off-load contaminated water into the waste liquid carrier. A waste carrier is a vessel that collects contaminated water and transports it to shore.

3 and 4 , the third outlet 43 of the first collection pit 35 is connected to an oil-water holding tank 72 via a conduit 71 . The oil-water holding tank 72 is a tank for temporarily storing oil and a liquid mixed with water.

The outlet of the oil-water holding tank 72 is connected to the oil-water separator 78 via a conduit 77 provided with a pump 76 . Pump 76 supplies liquid from oil water holding tank 72 to oil water separator 78 via conduit 77 . The oil-water separator 78 may be a hydrocyclone, and may separate oil and water, respectively. The oil-water separator 78 has a water outlet for discharging the separated water and an oil outlet for discharging oil. The second discharge conduit 81 is connected to the water outlet of the oil-water separator 78 . The second discharge conduit 81 has, at its downstream end, a second discharge outlet 82 for discharging water into the sea.

The oil outlet of the oil-water separator 78 is connected to the waste oil storage tank 85 through a conduit 84 . The waste oil storage tank 85 is a tank for storing a liquid containing oil. A second unloading pipe 86 with a pump 87 is connected to a waste oil storage tank 85 . The second unloading pipe 86 may be connected with the receiving port of the waste liquid carrier, and the oil-containing liquid in the waste oil storage tank 85 may be unloaded into the waste liquid carrier.

A fourth outlet 44 of the first collection pit 35 is connected to a waste oil storage tank 85 via a conduit 89 having a manual valve 88 . The fourth outlet 44 is connected to the conduit 71 via a conduit 92 having a manual valve 91 .

A conduit 32 extending from the oil module 6 is connected to a second collection pit 94 (second oil-water separator). The second collection pit 94 has a configuration similar to that of the first collection pit 35 , and includes a vertically extending partition wall 95 , a third chamber 96 and a fourth chamber 97 partitioned by the partition wall 95 . ), and a connecting passage 98 formed in the lower portion of the partition wall 95 and connecting the third chamber 96 and the fourth chamber 97 . A conduit 32 is connected to the third chamber 96 . An upper portion of the fourth chamber 97 is provided with a fifth outlet 101 , an upper portion of the third chamber 96 is provided with a sixth outlet 102 , and a lower portion of the third chamber 96 is provided with A seventh outlet 103 is provided. When the amount of liquid stored in the second collection pit 94 exceeds a certain amount, the liquid overflows from the fifth outlet 101 and the sixth outlet 102 . Since oil is lighter than water, the oil contained in the liquid supplied from the conduit 32 to the second collection pit 94 collects near the liquid surface of the third chamber 96 . Accordingly, the liquid containing little oil (water) flows outward from the fifth outlet 101 , and the liquid containing much oil flows outward from the sixth outlet 102 . The second collection pit 94 functions as an oil-water separator.

As shown in FIG. 4 , a third exhaust conduit 104 (a second exhaust conduit) is connected to the fifth outlet 101 of the second collection pit 94 . The third exhaust conduit 104 has, at its downstream end, a third outlet 105 for draining the liquid into the sea. A sixth outlet 102 of the second collection pit 94 is connected to the oil water holding tank 72 via a conduit 107 . A seventh outlet 103 of the second collection pit 94 is connected to a waste oil storage tank 85 via a conduit 109 having a manual valve 108 . The seventh outlet 103 is connected to the conduit 107 via a conduit 112 having a manual valve 111 .

As shown in FIG. 1 , a first collection pit 35 and a second collection pit 94 are disposed on the deck 3 . The first collection pit 35 is disposed below the collection floor 11 of the chemical module 5 so that the liquid in the conduit 24 can flow to the first collection pit 35 by gravity. The second collection pit 94 is disposed below the collection bottom 11 of the oil module 6 so that the liquid in the conduit 32 can flow to the second collection pit 94 by gravity.

A temporary storage tank 47 , an oil water holding tank 72 and a waste oil storage tank 85 are arranged in the hull 2 , ie under the deck 3 . As a result, the liquid in the first collection pit 35 can flow to the temporary storage tank 47 , the oil water holding tank 72 , and the waste oil storage tank 85 by gravity. The liquid in the second collection pit 94 may flow to the oil water holding tank 72 and the waste oil storage tank 85 by gravity.

A contaminated water storage tank 58 is arranged in the hull 2 below a temporary storage tank 47 . As a result, the liquid in the temporary storage tank 47 can flow into the contaminated water storage tank 58 by gravity. A chemical discharge drum 66 is disposed on the deck 3 . As a result, the liquid in the chemical discharge drum 66 may flow to the contaminated water storage tank 58 by gravity.

The first discharge outlet 56 is preferably disposed lower than the temporary storage tank 47 . As a result, the liquid in the temporary storage tank 47 can flow to the first discharge outlet 56 by gravity. In addition, the second discharge outlet 82 is preferably disposed at a lower level than the oil-water separator 78 . The oil-water separator 78 is disposed on the bottom portions 11 , 12 of the oil module 6 . Also, the third discharge outlet 105 is preferably disposed at a lower level than the fifth outlet 101 of the second collection pit 94 .

The capacity of the temporary storage tank 47 is preferably set to be greater than or equal to the sum of the maximum leakage of chemicals from the chemical module 5 and the maximum daily rainfall falling on all chemical modules 5 .

Hereinafter, the operation of the wastewater treatment system 10 configured as described above will be described. Rainwater falling on each chemical module 5 falls through the grid bottoms 28 of each top layer bottom 12 and reaches the collection bottom 11 . Rainwater is collected in the ditch 21 of the collection floor 11 and the discharge box 22 and flows through the conduit 24 to the first collection pit 35 . When the chemical leaks from some of the first devices 13 , the chemical is collected in a drip pan 26 provided below the first devices 13 and through conduit 31 and conduit 24 . It is delivered to the first collection pit 35 . As chemical leaks from each of the first devices 13 , the drip pan 26 may minimize the area where the chemical spreads in each of the bottoms 11 , 12 . When the chemical flows beyond the drip pan 26 and into each of the bottoms 11 , 12 , the chemical collects in the ditch 21 and discharge box 22 of the collecting bottom in the same manner as rainwater. As previously described, the chemical liquid and rainwater produced in each chemical module 5 are collected in a first collection pit 35 .

The liquid collected in the first collection pit 35 is separated into oil and water, and the water is transferred from the first outlet 41 to the temporary storage tank 47 through a conduit 46 . When a large amount of oily water is collected in the first collection pit 35 , the oily water overflows from the third outlet 43 and is delivered to the oily water holding tank 72 through a conduit 71 . .

By opening the manual valve 88 , the oil collected in the first chamber 37 of the first collection pit 35 is transferred from the fourth outlet 44 through the conduit 89 to the waste oil storage tank 85 . . By opening the manual valve 91 , the oil stored in the first chamber 37 of the first collection pit 35 is discharged from the fourth outlet 44 through the conduit 92 and the conduit 71 to the oil water holding tank 72 . ) is transferred to By opening the manual valve 48 , the liquid in the first collection pit 35 is delivered from the second outlet 42 through the conduits 49 and 46 to the temporary storage tank 47 .

The control device 63 determines whether the liquid stored in the temporary storage tank 47 is to be discharged to the sea or stored in the contaminated water storage tank 58 . When the liquid level in the temporary storage tank 47 is greater than or equal to the predetermined determination value and the concentration of the chemical in the liquid is lower than the predetermined determination value, the control device 63 drives the pump 51, and the first control valve ( 55) and close the second control valve 57. When the liquid level in the temporary storage tank 47 is equal to or greater than the predetermined determination value and the concentration of the chemical in the liquid is equal to or greater than the predetermined determination value, the control device 63 drives the pump 51 and the first control valve 55 ) and open the second control valve 57 . Therefore, if the chemical concentration of the liquid is lower than the prescribed value, the liquid is discharged into the sea, and if the concentration of the chemical in the liquid is higher than the prescribed value, the liquid is stored in the contaminated water storage tank 58 .

Oil leaking from the outside of the drip pan 26 on each oil module 6 and rainwater falling there, like chemicals leaking from chemical module 5 and rainwater falling therein, are It falls through the bottom 28 , collects in the ditch 21 of the collection bottom 11 and the discharge box 22 , and flows through the conduit 32 to the second collection pit 94 . When oil leaks from some of the second devices 14 , the oil collects in a drip pan 26 provided below the second device 14 , and collects a second through conduits 33 and 32 . transmitted to the pit 94 . As oil leaks from each of the second devices 14 , the drip pan 26 can minimize the area where the oil spreads from each of the bottoms 11 , 12 . As mentioned earlier, rainwater and oil produced in each oil module 6 are collected in a second collection pit 94 .

The liquid collected in the second collection pit 94 is separated into oil and water, and the water is discharged into the sea from the fifth outlet 101 through the third discharge conduit 104 . Oil is delivered from the sixth outlet 102 to the oil water holding tank 72 via a conduit 107 . By opening the manual valve 108 , the oil collected in the third chamber 96 of the second collection pit 94 is transferred from the seventh outlet 103 to the waste oil storage tank 85 through the conduit 109 . . By opening the manual valve 111, the oil collected in the third chamber 96 of the second collection pit 94 is discharged from the seventh outlet 103 through the conduit 112 and the conduit 107 into the oil water holding tank ( 72) is transferred.

The liquid stored in the oil-water holding tank 72 is transferred to the oil-water separator 78 through a conduit 77 to be separated into oil and water. Water is discharged from the water outlet of the oil-water separator 78 into the sea through the second discharge conduit 81 . Oil is delivered from the oil outlet of the oil-water separator 78 to the waste oil storage tank 85 through a conduit 84 .

The contaminated water stored in the contaminated water storage tank 58 and the oil stored in the waste oil storage tank 85 are unloaded into the waste liquid carrier.

Since the wastewater treatment system 10 discharges liquid into the sea whose concentration of the chemical is lower than a prescribed value, the amount of liquid stored in the contaminated water storage tank 58 can be reduced. As a result, the capacity of the contaminated water storage tank 58 can be reduced.

While the present invention has been described in terms of preferred embodiments thereof, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the scope of the present invention. For example, the first control valve 55 and the second control valve 57 may be changed to manual valves. In this case, the operator discharges the liquid stored in the temporary storage tank 47 to the sea or transfers it to the contaminated water storage tank 58, based on the detection results of the chemical detection device 61 and the liquid level meter 62. Thus, the manual valve is operated. In other implementations, the modules 5 , 6 may not have a top bottom 12 , and may have only a single collection bottom 11 .

1: FPSO
2: Hull
3: deck
5: Chemistry module
6: Oil module
10: Wastewater treatment system
11: collecting floor
12: upper floor
13: first device
14: second device
21: ditch
22: discharge box
26: drip pan (drip pan)
28: grating floor
35: first collection pit
47: temporary storage tank
52: first exhaust conduit
55: first control valve
57: second control valve
58: polluted water storage tank
61: chemical detection device
62: liquid level meter
63: control device
72: oil holding tank
78: oil-water separator
81: second exhaust conduit
85: waste oil storage tank
94: second collection pit

Claims (11)

A wastewater treatment system for FPSO comprising a chemical plant, comprising:
wherein the chemical plant comprises a plurality of first devices;
The wastewater treatment system for FPSO is
a liquid receiver provided below at least one of the first devices, the liquid receiver containing rainwater and a liquid containing chemicals that may have leaked from the first device;
a temporary storage tank connected to the liquid container through a conduit, the temporary storage tank temporarily storing the liquid collected in the liquid container;
a drain conduit connected to said temporary storage tank and having a first valve, said drain conduit for draining liquid stored in said temporary storage tank into the sea; and
a contaminated water storage tank connected to the temporary storage tank via a conduit having a second valve;
The FPSO includes a hull and a plurality of floors vertically arranged on the hull,
the plurality of floors comprises a collecting floor and at least one upper floor provided above the collecting floor;
said collection bottom has a gutter, said gutter collecting liquid flowing on a surface of said collection bottom, said gutter being connected to said temporary storage tank via a conduit;
each said upper floor has several grating floors,
and the liquid receiver is provided on the collection bottom or the upper bottom. The method of claim 1,
an oil-water separator provided between the liquid container and the temporary storage tank, the oil-water separator separating oil from the liquid collected in the liquid container; and
A waste oil storage tank connected to the oil-water separator through a conduit, and a waste oil storage tank for storing the oil separated by the oil-water separator. The wastewater treatment system for FPSO according to claim 1, further comprising a detector for detecting chemicals in the liquid stored in the temporary storage tank. 4. The wastewater treatment system for FPSO according to claim 3, further comprising a control device for controlling said first valve and said second valve based on a concentration of a chemical in said liquid detected by said detector. 3. The method of claim 2,
the FPSO comprises a hull and a collection bottom on the hull,
the collection bottom has a ditch, the ditch collects liquid flowing on the surface of the collection bottom, and the ditch is connected to the temporary storage tank through a conduit;
wherein the liquid receiver is provided on the collection bottom;
Wastewater treatment system for FPSO. 6. The wastewater treatment system for FPSO according to claim 2 or 5, wherein the oil-water separator is provided on a hull deck. The wastewater treatment system for FPSO according to claim 5, wherein the temporary storage tank is provided in an upper part of the hull, and the contaminated water storage tank is provided below the temporary storage tank in the hull. The wastewater treatment system of claim 1 , wherein the first device comprises an acid degassing device that uses an amine to adsorb acid gas. 2. The wastewater treatment system of claim 1, wherein the first apparatus comprises an inhibitor of hydrate formation regenerator for treating monoethylene glycol. The method of claim 2, wherein the wastewater treatment system for FPSO is
a second liquid receiver provided below at least one of the second devices, comprising: a second liquid receiver for receiving rainwater and a liquid containing oil that may have leaked from the second device;
a second oil-water separator connected to the second liquid receiver through a conduit, the second oil-water separator separating oil from the liquid collected in the second liquid receiver; and
A second discharge conduit connected to the second oil-water separator, a second discharge conduit for discharging the water separated from the oil by the second oil-water separator to the sea; further comprising,
The second oil-water separator is connected to the waste oil storage tank through a conduit for transferring the oil separated by the second oil-water separator to the waste oil storage tank,
Wastewater treatment system for FPSO. delete

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