Acetylene Hydrogenation Feed Temperature Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current acetylene hydrogenation processes in olefin production face challenges with fluctuating hydrogen concentrations due to changes in hydrocarbon feedstocks, leading to thermal runaway and acetylene breakthrough, which affect product quality and safety.

Innovation Solution

The method involves determining hydrogen concentrations in the acetylene hydrogenation unit and adjusting the temperature and CO concentration to maintain desired acetylene target levels, using a heat exchanger to control the hydrogenation feed temperature and adding supplemental CO to stabilize the process.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If the hydrogen concentration in the feed to the acetylene hydrogenation unit increases due to lighter feedstock, then the acetylene conversion efficiency improves, but the olefin selectivity decreases leading to thermal runaway

Engineering Contradiction:
Improveacetylene conversion efficiencyVSAvoidthermal runaway risk
Core Design Contradiction:
ProductivityVSObject-generated harmful factors

Solution Approach 1:

The patent applies dynamics by making the acetylene hydrogenation unit's operating conditions adjustable and responsive to changing feed composition. The system dynamically adapts to varying hydrogen concentrations by modifying operational parameters to maintain safe and efficient operation across different feedstock conditions

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent implements parameter changes by adjusting operational parameters (such as temperature, pressure, or catalyst conditions) in response to detected hydrogen concentration levels. This allows the system to optimize acetylene conversion while preventing excessive olefin hydrogenation and thermal runaway

Inventive Principle:
Principle #35Parameter changes

2Object-generated harmful factors

If the hydrogen concentration in the feed to the acetylene hydrogenation unit decreases due to heavier feedstock, then the olefin selectivity improves, but the acetylene conversion efficiency decreases leading to acetylene breakthrough

Engineering Contradiction:
Improveolefin selectivityVSAvoidacetylene conversion efficiency
Core Design Contradiction:
Object-generated harmful factorsVSProductivity

Solution Approach 1:

The system dynamically adjusts operating parameters based on real-time or monitored hydrogen concentration levels in the feed. This dynamic adaptation ensures that when hydrogen concentration decreases, the system compensates to maintain adequate acetylene conversion while preserving olefin selectivity

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent employs feedback mechanisms by monitoring hydrogen concentration in the feed and using this information to adjust operational parameters. This closed-loop control ensures the system responds appropriately to composition changes, maintaining both safety and product quality

Inventive Principle:
Principle #23Feedback

3Adaptability or versatility

If the steam cracking unit operates with frequent feedstock changes to respond to market fluctuations, then the adaptability of the olefin production process improves, but the stability of the acetylene hydrogenation unit deteriorates

Engineering Contradiction:
Improvefeedstock flexibilityVSAvoidhydrogenation unit operational stability
Core Design Contradiction:
Adaptability or versatilityVSStability of the object's composition

Solution Approach 1:

The patent makes the acetylene hydrogenation unit dynamic and adaptable to changing feed conditions. By enabling the unit to adjust its operating parameters in response to varying hydrogen concentrations from different feedstocks, the system maintains stability despite frequent upstream changes

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The system achieves universality by designing the acetylene hydrogenation unit to handle multiple feedstock types and compositions. The unit can effectively process feeds with varying hydrogen concentrations from different steam cracking operations, making the overall process versatile while maintaining operational stability

Inventive Principle:
Principle #6Universality (Multi-functionality)

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 thermal runaway and acetylene breakthrough, ensuring consistent product quality and safety by dynamically adjusting operating conditions in response to feedstock changes.

Implementation Method 1

using a heat exchanger to control the hydrogenation feed temperature

Methodology Applied
Scientific EffectHeat exchange: Heat Exchanger

Implementation Method 2

contacting the hydrogenation feed with an acetylene hydrogenation catalyst, the contacting causing hydrogenation of at least a portion of the acetylene of the hydrogenation feed

Methodology Applied
Scientific EffectCatalysis: Catalysis

Implementation Method 3

hydrogenation of at least a portion of the acetylene of the hydrogenation feed to produce a hydrogenation effluent

Methodology Applied
Scientific EffectHydrogenation: Hydrogenation

Implementation Method 4

hydrocarbon cracking (e.g., steam cracking) may be used to produce olefins from a hydrocarbon stream

Methodology Applied
Scientific EffectThermal decomposition: Pyrolysis

Data Source

PatentEP3931169B1Methods for operating acetylene hydrogenation units in olefin production processes
Publication Date: 2023.09.27 DOW GLOBAL TECHNOLOGIES LLC
  • EP3931169B1 patent drawingFigure 1
  • EP3931169B1 patent drawingFigure 2
  • EP3931169B1 patent drawingFigure 3

AI summary

A method for selectively hydrogenating acetylene in a cracked gas from a steam cracking unit for producing olefins may include separating a hydrogenation feed from the cracked gas. The hydrogenation feed may include acetylene, hydrogen, carbon monoxide, and at least one product. The method may further include contacting the hydrogenation feed with an acetylene hydrogenation catalyst, the contacting causing hydrogenation of at least a portion of the acetylene of the hydrogenation feed to produce a hydrogenation effluent. In response to a change in a composition of a feedstock to the steam cracking unit that results in a change in a hydrogen concentration in the hydrogenation feed, the method may further include determining the hydrogen concentration in the hydrogenation feed and increasing or decreasing a temperature of the hydrogenation feed based on the determined hydrogen concentration of the hydrogenation feed.