PSA Dryer for Hydrogen Purification

Solution Overview

Problem

Chlorided alumina catalysts in isomerization processes are sensitive to water and carbon oxides, leading to catalyst deactivation, and existing methods require multiple treatment systems that increase costs and complexity.

Innovation Solution

A single pressure swing (PSA) dryer system is used to simultaneously remove water and carbon oxides from hydrogen streams, utilizing adsorbents like alumina, silica gel, and molecular sieves, which contact the hydrogen stream at specific operating conditions to produce a dry and contaminant-reduced effluent.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If multiple separate treatment systems (methanator for carbon monoxide and molecular sieve for water) are used to remove contaminants, then the catalyst is protected from deactivation, but the capital equipment costs and operating costs increase significantly

Engineering Contradiction:

Improvecatalyst protection from deactivationVSAvoidmultiple treatment systems

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent combines the functions of carbon monoxide removal (methanator) and water removal (molecular sieve drier) into a single integrated pressure swing adsorption (PSA) system. This single system uses multiple adsorbent beds that can simultaneously or sequentially remove both contaminants from the hydrogen stream, eliminating the need for separate treatment systems while maintaining catalyst protection.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The PSA system is designed to perform multiple functions: removing carbon monoxide, removing water, and producing purified hydrogen all within a single apparatus. The system uses multiple adsorbent beds with different selectivities to achieve universal contaminant removal, replacing the need for specialized separate systems for each contaminant type.

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Reliability

If multiple separate treatment systems are used to remove water and carbon oxides, then contaminant removal effectiveness is achieved, but the system design and operation become more complex

Engineering Contradiction:

Improvecontaminant removal effectivenessVSAvoidsystem operation simplicity

Core Design Contradiction:

ReliabilityVSEase of operation

Solution Approach 1:

The patent combines the functions of carbon monoxide removal (methanator) and water removal (molecular sieve drier) into a single integrated pressure swing adsorption (PSA) system. This single system uses multiple adsorbent beds that can simultaneously or sequentially remove both contaminants from the hydrogen stream, eliminating the need for separate treatment systems while maintaining catalyst protection.

Inventive Principle:

Principle #5Merging (Combining)

3Reliability

If traditional two bed drier system is used to remove water, then water removal is effective, but carbon oxide removal capacity is insufficient

Engineering Contradiction:

Improvewater removal effectivenessVSAvoidcarbon oxide removal capacity

Core Design Contradiction:

ReliabilityVSQuantity of substance

Solution Approach 1:

The patent combines the functions of carbon monoxide removal (methanator) and water removal (molecular sieve drier) into a single integrated pressure swing adsorption (PSA) system. This single system uses multiple adsorbent beds that can simultaneously or sequentially remove both contaminants from the hydrogen stream, eliminating the need for separate treatment systems while maintaining catalyst protection.

Inventive Principle:

Principle #5Merging (Combining)

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 capital and operating costs, simplifies the system design, and prevents catalyst deactivation by achieving high-purity hydrogen with reduced contaminants, allowing for efficient use in isomerization units without the need for multiple treatment systems.

Implementation Method 1

The hydrogen stream is contacted with an adsorbent in the adsorbent column at first operating conditions to remove a portion of at least one contaminant

Methodology Applied

Scientific EffectAdsorption: Adsorption

Implementation Method 2

The second effluent stream is passed to a single drying zone at second operating conditions to produce a dry hydrogen stream

Methodology Applied

Scientific EffectDrying: Desiccation

Data Source

PatentUS11135542B2Processes and apparatuses for removing contaminants from hydrogen streams

Publication Date: 2021.10.05 UOP LLC

AI summary

This present disclosure relates to processes and apparatuses for removing contaminants from hydrogen streams. More specifically, the present disclosure relates to processes and apparatuses wherein hydrogen is used in units that utilize catalysts that are sensitive to oxygenates. The contaminants like carbon oxides and water are removed simultaneously from the hydrogen stream to provide a rich hydrogen stream with high purity to units that utilizes catalysts that are sensitive to oxygenates.