JPS6057097A - Method to obtain gas with different component in cold liquefied gas storage tank - Google Patents

Abstract

PURPOSE:To obtain gas with different component in a liquefied gas storage tank by applying heat to gas from outside by incorporating a heat exchanger in a cold liquefied gas storage tank, evaporating only the component of high specific volatility, and introducing it outside the tank. CONSTITUTION:Heat medium which is heated in an outer heat exchanger 7 proceeds to a heat-exchanger 5 in a tank 1 through a circulating line 6, and here it applies heat to LNG in the tank and only the high volatility component in the LNG is evaporated in the upper space in the tank. The evaporated gas is introduced outside the tank through an evaporating gas line 9, and it is boosted by a compressor 10 and sent to the destination. The outer beat exchanger 7 performs supplying of heat toward a heat medium of the circulating line 6 by a heat supplying medium circulating line 8.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for obtaining gases having different components from a gaseous mixture.

As shown in Table 1, LNG consists of various components, and when LNG is normally used as fuel fuel '1, each component is vaporized and consumed as a mixture. On the other hand, various reactors or chemical raw material manufacturers that use LNG as fuel have a desire to use, for example, only the methane component among the components shown in Table 1. Because we do not use a method of vaporizing and consuming only the different ingredients,
In particular, there are requests from city gas consumers to supply waste containing only certain components.

The present invention has been proposed in response to the above-mentioned needs, and an object of the present invention is to propose a method of obtaining gases having different components using an extremely simple method.

As a means to achieve the above object, the present invention first utilizes a low temperature liquefied natural gas storage tank (hereinafter referred to as "tank"). Furthermore, since each component of LNG has a different specific volatility, heat of vaporization suitable for each component is given to the LNG in the tank, volatile gas is stored in the upper space of the tank, and this is led out of the tank. The method of consumption was adopted.

Next, as a method of applying heat to the LNG inside the tank, a method was adopted in which a heat exchanger was inserted into the tank and a heat medium was circulated to the heat exchanger from outside the tank.

The attached drawing shows an embodiment of the present invention having the above-mentioned configuration, in which 1 is a tank, 2 is a receiving line, 3 is a liquid transfer line, 4 is a liquid transfer pump, and 5 is immersed in LNG in the tank 1. 6 is a heat medium circulation line for circulating the heat medium in the heat exchanger 5; 7 is an external heat exchanger, and 6 is a heat medium circulation line for circulating the heat medium in the heat medium circulation line 6; It is for heat replenishment. , 8 indicates a heat replenishment medium circulation line. Note that as the medium passed through the heat supply medium circulation line 8, for example, natural gas vaporized in a paper riser may be used.

9 is a volatile gas line for leading the highly volatile gas stored in the upper space of the tank 1 to the outside of the tank 1, and 10 is a compressor.

In the first embodiment, the heat medium heated in the external heat exchanger 7 reaches the heat exchanger 5 in the tank 1 via the circulation line 6, where it gives heat to the LNG in the tank 1, and the LNG Among them, only the highly volatile components are volatilized into the upper space inside the tank 1. Then, the volatile gas is led out of the tank 1 via the volatile gas line 9, pressurized by the compressor 10, and sent to the target consumption base.

As described above, the present invention includes a heat exchanger installed in a tank,
By circulating the heat medium through this heat exchanger, the LN in the tank is
By applying heat to G and forcibly separating only the highly volatile gas in the tank and leading it out of the tank, this can be consumed, making it possible for consumers who wish to use gas with specific components. In contrast, it has the effect of being able to respond simply with the necessary equipment.

Furthermore, in the present invention, the heat medium cooled by the heat exchanger inside the tank is circulated outside the tank via the heat medium line, so the cold heat recovered by this heat medium can be used by passing through the tank lid. can.

[Brief explanation of the drawing]

The figure is a system diagram showing one embodiment of the present invention. 1...tank?・・・・・・Acceptance line, 3
...Liquid transfer line, 4...Liquid transfer pump, 5...Heat exchanger, 6...Heat medium circulation line, 7...・External heat exchanger, 8--Heat replenishment medium circulation line, 9... Volatile gas line, 10
······compressor.

Claims (1)

[Claims] A heat exchanger is installed in the low-temperature liquefied gas storage tank, and a heat medium is circulated through the heat exchanger from the outside to provide heat to the low-temperature liquefied gas in the tank, and the low-temperature liquefied gas components with high relative volatility are A method of obtaining gases with different components in a low-temperature liquefied gas storage tank by volatilizing only the liquefied gas and leading it out of the tank.