Hydrodesulfurizer Steam Condensation Control in Hydrogen Generators

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The activities of the hydrodesulfurization catalyst in hydrogen generating apparatuses are decreased due to steam condensation, which is exacerbated by raw material purging methods that do not effectively manage temperature and steam flow, leading to potential carbon deposition and reduced catalyst efficiency.

Innovation Solution

Implementing a control mechanism that recycles hydrogen-containing gas to reduce water condensation in the hydrodesulfurizer by purging the apparatus with raw material before the temperature drops to levels that allow carbon deposition, and using an adsorbent desulfurizer to remove sulfur compounds upstream, ensuring the hydrodesulfurization catalyst remains active even when hydrogen supply is stopped.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If raw material purging is performed to remove steam from the hydrodesulfurizer, then steam condensation is reduced, but carbon deposition occurs on the reformation catalyst

Engineering Contradiction:
Improvesteam condensationVSAvoidcarbon deposition
Core Design Contradiction:
Object-affected harmful factorsVSObject-generated harmful factors

Solution Approach 1:

The patent applies preliminary action by purging the hydrodesulfurizer with raw material gas before the reformation catalyst temperature drops to the carbon deposition range. This timing ensures steam is removed while preventing carbon deposition on the catalyst, as the catalyst temperature is maintained above the carbon deposition threshold during the purge operation

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent applies local quality by differentiating the temperature requirements for different components: the hydrodesulfurizer is purged to remove steam, while the reformation catalyst is maintained at a temperature that prevents carbon deposition. This localized temperature management allows steam removal without causing carbon deposition on the catalyst

Inventive Principle:
Principle #3Local quality

2Reliability

If hydrogen-containing gas recycling is stopped to prevent water condensation, then catalyst activity is maintained, but sulfur compound removal efficiency decreases

Engineering Contradiction:
Improvecatalyst activityVSAvoidsulfur compound removal efficiency
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The patent applies preliminary action by performing raw material gas purging before hydrogen-containing gas recycling is completely stopped. This preliminary purge removes steam from the hydrodesulfurizer, preventing water condensation that would deactivate the catalyst, while the system maintains sulfur compound removal capability through the purged raw material gas

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent applies continuity of useful action by maintaining raw material gas flow through the hydrodesulfurizer during the transition period when hydrogen-containing gas recycling is reduced. This continuous raw material flow ensures both steam removal and sulfur compound removal, preventing catalyst deactivation while maintaining productivity

Inventive Principle:
Principle #20Continuity of useful action

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 water condensation in the hydrodesulfurizer, minimizes catalyst deactivation, and prevents carbon deposition in the reformer, thereby maintaining catalyst activity and system efficiency.

Implementation Method 1

a second desulfurizer that performs hydrodesulfurization of the sulfur compound in the raw material gas supplied to the reformer

Methodology Applied
Scientific EffectHydrodesulfurization: Hydrogenation

Implementation Method 2

a first desulfurizer that adsorptively removes a sulfur compound in a raw material gas supplied to a reformer

Methodology Applied
Scientific EffectAdsorption: Adsorption

Implementation Method 3

the activities of the hydrodesulfurization catalyst in hydrogen generating apparatuses are decreased due to steam condensation

Methodology Applied
Scientific EffectCondensation: Condensation

Data Source

PatentEP2897204B1Hydrogen generating apparatus, fuel cell system, and methods of operating them
Publication Date: 2019.10.02 PANASONIC HOLDINGS CORP
  • EP2897204B1 patent drawingFigure 1~2
  • EP2897204B1 patent drawingFigure 3~4
  • EP2897204B1 patent drawingFigure 5~6

AI summary

A hydrogen generating apparatus(100) includes a reformer(2) generating hydrogen-containing gas through a reforming reaction, a raw material supplier(4) supplying a raw material to the reformer(2), a reaction gas supplier(6) supplying reaction gas other than the raw material to the reformer(2), a hydro-desulfurizer(8) removing a sulfur compound in the raw material supplied to the reformer(2), a recycle flow passage(10) through which part of the hydrogen-containing gas generated by the reformer(2) is supplied to the hydro-desulfurizer(8), a closing device(12) that closes the recycle flow passage(10), and a controller(14) that, when stopping operation, closes the closing device(12) and controls the raw material supplier(4) and the reaction gas supplier(6) such that the raw material and the reaction gas are supplied to the reformer(2), before a temperature of the reformer(2) drops down to a temperature at which deposition of carbon from the raw material on a reformation catalyst disposed inside the reformer(2) is suppressed.