LNG Regasification Heat Exchanger with Self-Preheating

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Regasification plants with shell-and-tube-type vaporizers face challenges due to high costs and complex designs, and the use of additional heat media like propane complicates the preheating process, making them unsuitable for offshore installations.

Innovation Solution

A regasification method involving a preheating heat exchanger that uses the own heat of regasified gas to preheat liquefied gas, followed by a shell-and-tube-type heat exchanger using seawater or fresh water, eliminating the need for additional heat media and simplifying the configuration.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a shell-and-tube-type heat exchanger with two water chambers is used to preheat LNG and prevent freezing, then the reliability is improved, but the device complexity increases

Engineering Contradiction:
Improvefreezing preventionVSAvoidheat exchanger structure
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The invention preheats LNG before it enters the main heat exchanger by using the warmed seawater from the first water chamber. This preliminary heating action raises the LNG temperature above the freezing point before the main heating process, preventing freezing without requiring complex dual-chamber configuration. The preheating is achieved by guiding seawater through a first water chamber and using it to preheat LNG in a second water chamber.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The heat exchanger is divided into two functional segments: a first water chamber for initial heating of seawater, and a second water chamber for preheating LNG using the warmed seawater. This segmentation allows the system to prevent freezing through a simpler sequential process rather than a complex integrated dual-function chamber.

Inventive Principle:
Principle #1Segmentation

2Productivity

If an ORV system is used for regasification, then the regasification capability is improved, but the device complexity and size increase

Engineering Contradiction:
Improveregasification capabilityVSAvoidsystem configuration
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The invention merges the preheating function and regasification function into a single integrated shell-and-tube heat exchanger system. The seawater serves dual purposes: first as a heating medium in the first water chamber, then as a preheating medium for LNG in the second water chamber. This combination eliminates the need for separate preheating equipment and ORV components, reducing overall system complexity while maintaining regasification capability.

Inventive Principle:
Principle #5Merging (Combining)

3Reliability

If additional heat media like propane are used for preheating, then the freezing risk is reduced, but the device complexity increases

Engineering Contradiction:
Improvefreezing risk reductionVSAvoidpreheating system
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The system uses seawater itself to preheat LNG, eliminating the need for additional heat media like propane. The seawater is warmed in the first water chamber and then used to preheat LNG in the second water chamber, creating a self-sufficient preheating system. This approach reduces freezing risk through thermal management while avoiding the complexity of handling and storing additional heat transfer fluids.

Inventive Principle:
Principle #25Self-service

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This approach reduces the risk of freezing and maintains heat exchange performance, allowing for the use of simpler, cost-effective shell-and-tube-type heat exchangers and enabling compact, efficient regasification in smaller installations.

Implementation Method 1

a preheating heat exchanger that preheats liquefied gas flowing through a preheated flow by a preheating fluid flowing through a preheating flow

Methodology Applied
Scientific EffectHeat transfer: Conduction (thermal)

Implementation Method 2

a first heat exchanger that regasifies the liquefied gas preheated in the preheating heat exchanger by seawater or fresh water

Methodology Applied
Scientific EffectHeat transfer: Conduction (thermal)

Implementation Method 3

a second heat exchanger that regasifies the liquefied gas condensed through the preheating flow by seawater or fresh water

Methodology Applied
Scientific EffectHeat transfer: Conduction (thermal)

Data Source

PatentEP2682666B1Liquefied gas regasificaion device and method for manufacturing regasified gas
Publication Date: 2020.03.25 MITSUBISHI SHIPBUILDING CO LTD
  • EP2682666B1 patent drawingFigure 1~2
  • EP2682666B1 patent drawingFigure 3
  • EP2682666B1 patent drawingFigure 4

AI summary

A liquefied gas regasification plant which can regasify liquefied gas by a shell-and-tube-type heat exchanger with a simple configuration by preheating the liquefied gas with a simple configuration is provided. The liquefied gas regasification plant includes a preheating heat exchanger (3) that preheats LNG flowing through a preheated flow (3a) by gasification gas flowing through a preheating flow (3b), and a first shell-and-tube-type heat exchanger (5) that regasifies the LNG preheated in the preheating heat exchanger (3) by seawater or fresh water, the gas regasified in the first shell-and-tube-type heat exchanger (5) being guided to the preheating flow (3b), the liquefied gas regasification plant further including a second shell-and-tube-type heat exchanger (7) that regasifies the LNG condensed through the preheating flow (3b) by seawater or fresh water.