Device for adjusting methane value in natural gas

Abstract

The utility model provides a device for adjusting a methane value in natural gas. The device comprises a natural gas separation unit and an on-line methane value allocation unit, the natural gas separation unit consists of a booster pump, a gasifier, a first pneumatic control assembly, a second pneumatic control assembly, an absorption tower consisting of a cold washing part and a gasification part, a third pneumatic control assembly, a deethanization tower, a reboiler and a fourth pneumatic control assembly; the on-line methane value adjusting unit is composed of a fifth pneumatic control assembly, a recuperator and an on-line component monitoring module; the input end of the booster pump is connected with liquefied natural gas provided by the outside through a valve; the booster pump is used for outputting the pressurized natural gas to the absorption tower in two paths; methane value natural gas produced by the gasification part is fed into the on-line methane value allocation unit, and natural gas produced by the cold washing part enters the deethanization tower; the tower top of the deethanization tower is used for feeding methane value natural gas into the on-line methane value allocation unit; according to the utility model, the methane value of the natural gas for the engine is increased, and the benefit is maximized.

Description

Technical Field

[0001] The utility model belongs to the technical field of safe use of engine cylinders, and in particular relates to a device for regulating the methane value in natural gas. Background Art

[0002] The output of shaft power of a reciprocating engine is limited by the anti-knock performance of the fuel / air mixture. Generally, natural gas has better anti-knock performance than liquid fuel. If detonation occurs when natural gas is burned in the engine cylinder, the engine power will drop sharply, the fuel consumption will increase significantly, and in severe cases, it will cause piston or valve burnout, bearing rupture and other faults. At the same time, if detonation occurs when natural gas is burned in the cylinder of a reciprocating engine, the engine power will drop sharply and the unit will be damaged. Therefore, when using natural gas as a fuel for combustion, its anti-knock performance needs to be considered, and the important indicator for measuring the anti-knock performance of natural gas is the methane number. Utility Model Content

[0003] In view of the technical problems existing in the prior art, the utility model provides a device for adjusting the methane value in natural gas. The device is based on the raw material liquefied natural gas (LNG) components and is designed with a set of devices for separating and purifying methane, recovering light hydrocarbons and adjusting the methane value online. The utility model realizes high-precision extraction of the methane value of natural gas and effectively improves the C 3 The condensation rate and C 3+ The recovery rate is high, achieving energy saving and environmental protection; on the other hand, the utility model dilution gas supply line can adjust the methane value online to prevent the natural gas from deflagration in the engine cylinder.

[0004] In order to solve the existing technical problems, the utility model adopts the following technical solutions:

[0005] A device for adjusting the methane value in natural gas, comprising a device body; the device comprises a natural gas separation unit and an online methane value adjustment unit; the natural gas separation unit comprises a booster pump, a gasifier, a first gas control component, a second gas control component, an absorption tower consisting of a cold washing part and a gasification part, a third gas control component, a deethanizer, a reboiler and a fourth gas control component;

[0006] The online methane value adjustment unit is composed of a fifth gas control component, a recuperator and an online component monitoring module; wherein:

[0007] The input end of the booster pump is connected to the liquefied natural gas provided outside through a valve; the booster pump outputs the pressurized natural gas to the absorption tower in two ways, one of which directly enters the cold washing part of the absorption tower, and the other enters the vaporization part of the absorption tower kettle for separation after reheating; the methane value natural gas produced by the vaporization part is sent to the online methane value adjustment unit, and the natural gas in the cold washing part enters the deethanizer; the methane value natural gas is sent to the online methane value adjustment unit from the top of the deethanizer; the deethanizer kettle separates the liquid natural gas and outputs liquefied petroleum gas;

[0008] The reheater is used to reheat the low-temperature natural gas outputted from the gasification section of the absorption tower and the top of the deethanizer respectively;

[0009] The online component monitoring module determines the methane component in the reheated natural gas. When the methane value is higher than a preset value, the online component monitoring module turns on the fifth gas control component to add dilution gas to the high methane value natural gas.

[0010] Furthermore, the booster pump is used to boost the pressure of the input natural gas to 0.4MPa~3.6MPa; the natural gas transported to the gasifier for gasification accounts for 0~80% of the boosted natural gas, is gasified to 0℃~20℃ by the gasifier, and is in contact with another part of the boosted natural gas for heat exchange in the absorption tower.

[0011] Furthermore, the first air control component, the second air control component, the third air control component and the fourth air control component are all composed of flow sensors and valves.

[0012] Furthermore, the absorption tower and the deethanizer are either a packed tower or a plate tower.

[0013] Furthermore, the heat medium of the vaporizer, reboiler and recuperator can be water, heat transfer oil, air or other heating media.

[0014] Furthermore, the dilution gas is one of carbon dioxide, hydrogen and nitrogen, and the carbon dioxide, hydrogen and nitrogen can be gaseous or liquid.

[0015] Beneficial Effects

[0016] The utility model provides a natural gas control device for an engine cylinder. The device is based on the raw material liquefied natural gas (LNG) components and is designed to separate and purify methane, recover light hydrocarbons and adjust the methane value online. The device adopts the method of cold washing in an absorption tower and fractionation in a deethanizer, which can not only improve the accuracy of extracting the methane value of natural gas, but also reduce the C 3 and C 3+The components are separated and recovered to achieve stable operation of the engine cylinder and maximize benefits; the opening of the dilution gas replenishment line is adjusted through the online component monitoring module, and the methane value is adjusted online to prevent natural gas from deflagration in the engine cylinder. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of a process flow of a natural gas control device in an engine cylinder according to the utility model, wherein:

[0018] 100 Natural gas separation unit 200 Online methane value adjustment unit

[0019] P101 Booster PumpE101 GasifierT101 AbsorberT102 DeethanizerE102 Reheater

[0020] E103 reboiler 201 valve 202 first gas control component 203 second gas control component 204 third gas control component

[0021] 205 Fourth gas control component 206 Fifth gas control component AT online component monitoring module T101 a cold wash unit

[0022] T101 b Gasification section DETAILED DESCRIPTION

[0023] The following is combined with Figure 1 The utility model is specifically described as follows:

[0024] The utility model provides a natural gas control device for an engine cylinder, comprising a natural gas separation unit 100 and an online methane value adjustment unit 200; wherein: the natural gas separation unit is composed of a booster pump P101, a gasifier E101, a valve 201, a first gas control group 202, a second gas control component 203, an absorption tower T101, a third gas control component 204, a deethanizer T102, a reheater E102 and a fourth gas control component 205; the absorption tower T101 is composed of a cold washing part T101a and a gasification part T101b; the first gas control component 202, the second gas control component 203, the third gas control component 204 and the fourth gas control component 205 are all composed of flow meters and valves;

[0025] Wherein: the input end of the boost pump P101 is connected to the natural gas in the engine cylinder through a valve 201; the boost pump P101 outputs the pressurized natural gas to the absorption tower T101 in two ways; the boost pump P101 pressurizes the LNG (liquefied natural gas) from outside the device to 0.4MPa~3.6MPa; wherein: one way sequentially inputs the gasified natural gas to the cold washing part T101a of the absorption tower through the first gas control component 202 and the gasifier E101; the other way inputs the natural gas to the gasification part T101b of the absorption tower through the second gas control component 203; the cold washing part T101a cold washes the input natural gas, and then inputs the liquid phase mixed hydrocarbons to the deethanizer T102 for gas-liquid mass transfer separation; the gasification part T101 b The supercooled natural gas is sent to the natural gas detection unit 200 through the third gas control component 204; wherein: the pressurized LNG sent to the gasifier E101 for gasification accounts for 0-80% of the pressurized LNG, is gasified to 0℃-20℃ by the gasifier E101, and then contacts and exchanges heat with another part of the pressurized LNG in the absorption tower T101; one way of the output end of the deethanizer T102 sends the gaseous natural gas to the online methane value adjustment unit 200; the other way of its output end separates the liquid natural gas through the reboiler E103 and then outputs liquefied petroleum gas through the fourth gas control component 205; the absorption tower T101, the deethanizer T102 and the reboiler E103 are one of a packed tower and a plate tower.

[0026] The online methane value adjustment unit 200 is composed of a fifth gas control component 205, a recuperator E102 and an online component monitoring module AT; wherein:

[0027] The reheater E102 mixes the supercooled natural gas output from the absorption tower T101 and the gas phase natural gas output from the deethanizer to generate the natural gas to be tested; the online component monitoring module AT judges the methane component in the natural gas to be tested, and when the methane value is higher than the preset methane value, the online component monitoring module AT turns on the fifth gas control component 206 to add the dilution gas into the engine cylinder. The heat medium of the gasifier E101, the reboiler E103, and the reheater E102 can be one of water, heat transfer oil, air or other heating media. The dilution gas is one of carbon dioxide, hydrogen, and nitrogen, and the carbon dioxide, hydrogen, and nitrogen can be gaseous or liquid.

[0028] The actual production process of this utility model:

[0029] The process flow chart is as attached Figure 1As shown, the LNG logistics 101 from outside the device is pressurized to 0-1.6MPaG (logistics 102) by the booster pump P101 and is divided into two routes. Among them, 0-80% LNG (logistics 104) is transported to the vaporizer E101, vaporized to 0-20℃ and discharged as logistics 105, and directly contacted with another LNG logistics 103 in the absorption tower T101 for heat exchange, and the cold natural gas logistics 106 is produced from the top of the tower, and the liquid phase mixed hydrocarbon logistics 107 after cold washing enters the deethanizer T102 for gas-liquid mass transfer separation, and the gas phase logistics 108 of the deethanizer T102 and the cold natural gas mixed flow 109 produced from the top of the absorption tower T101 are reheated by the reheater E102 and transported to the outside of the device as NG natural gas; the liquid phase logistics 111 at the bottom of the deethanizer T102 is LPG liquefied petroleum gas.

[0030] Among them, the heat medium of the vaporizer E101, the recuperator E102, and the reboiler (E103) is heated by a heating medium (hot water, heat transfer oil, air or other heating medium). The logistics data are shown in Table 1:

[0031] Table 1 Stream composition table

[0032]

[0033]

[0034] 2. List of main equipment

[0035] Table 2 List of main equipment

[0036]

[0037] 3. Consumption

[0038] Table 3 Hot water consumption

[0039]

[0040] 4. Material balance of the device

[0041] The raw material of this device is LNG, and the products are natural gas (NG) and liquefied petroleum gas (LPG).

[0042] Table 4 Changes in parameters of each component in and out of the device

[0043]

[0044]

[0045] Although the utility model has been described above, the utility model is not limited to the above-mentioned specific embodiments. The above-mentioned specific embodiments are merely illustrative and not restrictive. Under the guidance of the utility model, ordinary technicians in this field can make many modifications without departing from the purpose of the utility model, which are all within the protection of the utility model.

Claims

1. A device for adjusting the methane value in natural gas, comprising a device body; characterized in that: The device comprises a natural gas separation unit and an online methane value adjustment unit; the natural gas separation unit is composed of a booster pump, a gasifier, a first gas control component, a second gas control component, an absorption tower composed of a cold washing part and a gasification part, a third gas control component, a deethanizer, a reboiler and a fourth gas control component; the online methane value adjustment unit is composed of a fifth gas control component, a recuperator and an online component monitoring module; wherein: The input end of the booster pump is connected to the liquefied natural gas provided outside through a valve; the booster pump outputs the pressurized natural gas to the absorption tower in two ways, one of which directly enters the cold washing part of the absorption tower, and the other enters the vaporization part of the absorption tower kettle for separation after reheating; the methane value natural gas produced by the vaporization part is sent to the online methane value adjustment unit, and the natural gas in the cold washing part enters the deethanizer; the methane value natural gas is sent to the online methane value adjustment unit from the top of the deethanizer; the deethanizer kettle separates the liquid natural gas and outputs liquefied petroleum gas; The reheater reheats the low-temperature natural gas output from the gasification section of the absorption tower and the top of the deethanizer respectively; the online component monitoring module judges the methane component in the reheated natural gas, and when the methane value is higher than the preset value, the online component monitoring module turns on the fifth gas control component to add dilution gas to the high methane value natural gas.

2. The device for adjusting the methane value in natural gas according to claim 1, characterized in that: The first air control component, the second air control component, the third air control component and the fourth air control component are all composed of flow sensors and valves.

3. The device for adjusting the methane value in natural gas according to claim 1, characterized in that: The absorption tower and the deethanizing tower are either a packed tower or a plate tower.

4. The device for adjusting the methane value in natural gas according to claim 1, characterized in that: The heat medium of the gasifier, reboiler and recuperator is water, heat transfer oil or air.

5. A device for adjusting the methane value in natural gas according to any one of claims 1 to 4, characterized in that: The dilution gas is one of carbon dioxide, hydrogen and nitrogen, and the dilution gas is in gaseous or liquid state.

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