CN205640212U

CN205640212U - Energy -saving BOG recovery unit of LNG gas station

Info

Publication number: CN205640212U
Application number: CN201620098691.8U
Authority: CN
Inventors: 张会平; 史秀芳; 张功
Original assignee: Individual
Current assignee: Individual
Priority date: 2016-02-01
Filing date: 2016-02-01
Publication date: 2016-10-12
Anticipated expiration: 2026-02-01

Abstract

The utility model discloses an energy -saving BOG recovery unit of LNG gas station, energy -saving BOG recovery unit of LNG gas station include low temperature LNG storage tank, be provided with coil pipe or tubular heat exchanger in the low temperature LNG storage tank, coil pipe or tubular heat exchanger pass through the inlet tube and are connected with outside low temperature liquid nitrogen storage tank. The beneficial effects of the utility model are that reduce greenhouse gas emission, improve the environment, the energy saving has certain economic benefits, nitrogen gas discharges safelyr, nontoxic than natural gas emission, and no combustion and explosion is dangerous, no electrical equipment, no electric spark causes dangerously, the liquid nitrogen price is not high, and the construction cost is low, maintains that cost of maintenance is low, and this process units realizes easily that the feasibility is high, is fit for extensively promoting at home.

Description

A kind of energy-saving LNG gas station BOG retracting device

Technical field

This utility model relates to LNG plant technical field, it particularly relates to a kind of energy-saving LNG gas station BOG reclaims Device.

Background technology

Liquefied natural gas (LNG) there is low temperature properties and vapo(u)rability, affected by external environment heat, LNG storage, transport During with work, can produce a number of LNG flash gas (BOG), LNG recepts the caloric increase, and the BOG of generation is also gradually increased, If be directly discharged in air, causing the wasting of resources to LNG gas station, meanwhile, the methane isothermal chamber gas in BOG gas was both Pollute environment, there is also burning, the potential safety hazard of blast.

The BOG recovery method that gas station is conventional at present has: pressure vessel reclaims square with L-CNG gas station compressor recovery etc. Method.

1, in the shortcoming of pressure vessel recovery method is gas station, personal gas regularity is poor, and gas consumption is difficult to coupling, works as BOG For more than taking, needing partial discharge；When BOG deficiency, gasifying section LNG is needed to use.

2, L-CNG gas station compressor recovery method must be L-CNG gas station, it is impossible to be simple LNG gas station, no So cannot store and sell CNG；Early stage need to put into Compressor Group, air accumulator, control system etc. costly；The later stage electricity charge, Equipment maintenance takes the highest.

Utility model content

The purpose of this utility model is to provide a kind of energy-saving LNG gas station BOG retracting device, solves in prior art The problem that LNG filling station BOG must discharge.

For realizing above-mentioned technical purpose, the technical solution of the utility model is achieved in that

A kind of energy-saving LNG gas station BOG retracting device, is arranged including in low temperature LNG storage tank, described low temperature LNG storage tank Coil pipe or tubular heat exchanger, coil pipe or tubular heat exchanger is had to be connected with outside low temperature liquid nitrogen storage tank by inlet tube.

Inlet under further, described low temperature LNG storage tank is provided with independent LNG gas returning port, the upper inlet of LNG, LNG, LNG liquid outlet.

Described low temperature liquid nitrogen storage tank can be small-sized liquid nitrogen storage tank, it is also possible to be liquid nitrogen tank car.

Use liquid nitrogen cooling liquid rapid to the gas in LNG storage tank, LNG liquid is lowered the temperature, in making storage tank simultaneously Pressure, temperature are down to desired value.And equipment, the BOG of pipeline generation outside LNG storage tank also can pass through LNG storage tank gas returning port, enter Cooling liquid in LNG storage tank, it is achieved LNG and L-CNG filling station BOG zero-emission.

The beneficial effects of the utility model:

1, reduce greenhouse gas emission, improve environment；Save the energy, there is certain economic benefit.

2, nitrogen discharge is safer compared with natural gas discharge, nontoxic, dangerous without combustion explosion；Without electrical equipment, without electric spark Initiation potential.

3, construction cost is low, maintenance and repair low cost.Liquid nitrogen is inexpensive, simply the 10% of LNG price, and easily buys, LNG and L-CNG station is the most applicable.If reclaiming LNG every day by the rate of gasification of LNG storage tank is 2% accounting, deduction liquid nitrogen cost (accounts for assembly This is 20% years old), also it is of great value, and this process unit is easily achieved, feasibility is high, is suitable for being widely popularized at home.

Accompanying drawing explanation

In order to be illustrated more clearly that this utility model embodiment or technical scheme of the prior art, below will be to embodiment The accompanying drawing used required in is briefly described, it should be apparent that, the accompanying drawing in describing below is the most of the present utility model Some embodiments, for those of ordinary skill in the art, on the premise of not paying creative work, it is also possible to according to this A little accompanying drawings obtain other accompanying drawing.

Fig. 1 is the layout signal according to the energy-saving LNG gas station BOG retracting device described in this utility model embodiment Figure.

In figure:

1, LNG storage tank；2, coil pipe or tubular heat exchanger；3, liquid ammonia storage tank；4, liquid Space；5, inlet tube；6, LNG return-air Mouthful；7, the upper inlet of LNG；8, inlet under LNG；9, LNG liquid outlet.

Detailed description of the invention

Below in conjunction with the accompanying drawing in this utility model embodiment, the technical scheme in this utility model embodiment is carried out Clearly and completely describe, it is clear that described embodiment is only a part of embodiment of this utility model rather than whole Embodiment.Based on the embodiment in this utility model, the every other embodiment that those of ordinary skill in the art are obtained, all belong to Scope in this utility model protection.

As it is shown in figure 1, according to the one energy-saving LNG gas station BOG retracting device described in this utility model embodiment, bag Include low temperature LNG storage tank 1, be provided with coil pipe or tubular heat exchanger 2, coil pipe or tubular heat exchanger 2 in described low temperature LNG storage tank 1 and lead to Cross inlet tube 5 to be connected with outside low temperature liquid nitrogen storage tank 3；Described low temperature LNG storage tank 1 is provided with on independent LNG gas returning port 6, LNG Inlet 8, LNG liquid outlet 9 under inlet 7, LNG.

Described low temperature liquid nitrogen storage tank 3 can be small-sized liquid nitrogen storage tank, it is also possible to be liquid nitrogen tank car.

Understand technique scheme of the present utility model for convenience, below by way of new to this practicality in specifically used mode The technique scheme of type is described in detail.

When specifically used:

Owing to liquid nitrogen boiling point at ambient pressure is about-196 DEG C, and LNG boiling point at ambient pressure is about-162 DEG C, liquid nitrogen boiling point temperature Degree is far below LNG boiling temperature, therefore BOG is liquefied by the cold energy of available liquid nitrogen again.When LNG storage tank 1 manufactures and designs in tank If a set of coil pipe or tubular heat exchanger 2, it has independent entrance and exit.When needs carry out BOG recovery, hold from inlet tube 5 Continuous injection liquid nitrogen, can be from outlet emptying.Liquid nitrogen by during coil pipe in coil pipe endothermic gasification, absorb gas phase and liquid phase in storage tank Make natural gas liquefaction, LNG temperature of liquid reduce after the heat of LNG, stop injecting liquid nitrogen when pressure of storage tank reaches expection, such as figure Shown in 1.Can be small-sized liquid nitrogen storage tank for injecting the equipment of liquid nitrogen according to various places practical situation, it is also possible to be that liquid nitrogen tank car is straight Connect injection.

The foregoing is only preferred embodiment of the present utility model, not in order to limit this utility model, all at this Within the spirit of utility model and principle, any modification, equivalent substitution and improvement etc. made, should be included in this utility model Protection domain within.

Claims

1. an energy-saving LNG gas station BOG retracting device, including low temperature LNG storage tank (1), it is characterised in that: described low temperature Be provided with in LNG storage tank (1) coil pipe or tubular heat exchanger (2), described coil pipe or tubular heat exchanger (2) by inlet tube (5) with Outside low temperature liquid nitrogen storage tank (3) connects.

Energy-saving LNG gas station the most according to claim 1 BOG retracting device, it is characterised in that: described low temperature LNG stores up Tank (1) is provided with independent LNG gas returning port (6).

Energy-saving LNG gas station the most according to claim 2 BOG retracting device, it is characterised in that: described low temperature LNG stores up Tank (1) is provided with inlet (8) under inlet on LNG (7), LNG, LNG liquid outlet (9).

4. according to the one energy-saving LNG gas station BOG retracting device described in any one of claim 1-3, it is characterised in that: institute Stating low temperature liquid nitrogen storage tank (3) is small-sized liquid nitrogen storage tank or liquid nitrogen tank car.