Two-Stage Adsorption Regeneration for Claus Tail Gas Sulfur Recovery
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current sulfur recovery methods, such as the Claus process, face challenges in achieving high sulfur removal and recovery efficiency due to stringent environmental regulations, requiring complex and expensive tail gas treatment units to reach efficiencies above 99.9%, which is not efficiently addressed by existing technologies.
Innovation Solution
A two-stage adsorption process involving a hydrogenation reactor, quench tower, and parallel-connected adsorption vessels with specific adsorbents like hydrophilic 3 Å molecular sieves and Cu-Y type zeolites, which convert and recover hydrogen sulfide from Claus tail gas, allowing for continuous operation and regeneration of adsorption vessels to enhance sulfur recovery efficiency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional Claus process is used, then sulfur recovery efficiency is improved (95-98%), but it cannot meet stringent environmental regulations requiring 99.9% or higher
Solution Approach 1:
The adsorption system is divided into multiple parallel adsorption vessels that operate in sequence through switching valves. This segmentation allows continuous operation where one vessel is adsorbing while another is regenerating, maintaining high sulfur recovery efficiency without requiring complex continuous regeneration systems.
Solution Approach 2:
The system employs periodic switching between adsorption and regeneration modes of different adsorption vessels. By periodically switching valves to transfer gas streams between vessels, the system achieves continuous high-efficiency sulfur recovery while simplifying the regeneration process through periodic rather than continuous operation.
2Reliability
If tail gas treatment unit is added to increase sulfur recovery to 99.9% or higher, then sulfur recovery efficiency is improved, but equipment complexity and cost increase
Solution Approach 1:
The system merges the adsorption and regeneration functions into a single integrated unit with multiple vessels and switching valves. This combination achieves 99.9% sulfur recovery efficiency while avoiding the need for separate complex treatment units, as the same vessels perform both sulfur capture and regeneration functions.
Solution Approach 2:
The adsorption vessels serve multiple functions: they capture sulfur during adsorption mode and undergo regeneration during different time periods. This multi-functionality allows a single system to achieve high sulfur recovery efficiency without requiring dedicated separate equipment for each function, thereby reducing overall equipment complexity.
3Productivity
If multiple parallel adsorption vessels are used for continuous operation, then productivity is improved, but device complexity increases
Solution Approach 1:
The system uses dynamic switching valves to redirect gas streams between parallel adsorption vessels based on operational requirements. This dynamic control enables continuous sulfur recovery by switching between vessels in real-time, achieving high productivity while managing complexity through automated rather than manual switching.
Solution Approach 2:
Multiple parallel adsorption vessels operate in a continuous cycle where one vessel performs sulfur adsorption while another undergoes regeneration. This continuous operation maintains constant sulfur recovery capability, improving productivity. The continuity is achieved through coordinated switching that ensures no interruption in the sulfur capture process, and the complexity is managed by the systematic cycling pattern rather than requiring complex control systems.
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
The process increases overall sulfur recovery to at least 99.90%, 99.93%, or 99.95%, providing a cost-effective and efficient solution for achieving high sulfur recovery efficiency without the need for complex and expensive tail gas treatment units.
Implementation Method 1
converting sulfur-containing compounds to hydrogen sulfide
Implementation Method 2
condensing and recovering liquid water
Implementation Method 3
adsorbing hydrogen sulfide
Implementation Method 4
desorbing hydrogen sulfide
Data Source
AI summary
Embodiments of the disclosure provide a method and system for sulfur recovery. A Claus tail gas stream is fed to a hydrogenation reactor to produce a hydrogenated gas stream. The hydrogenated gas stream is fed to a quench tower to produce a quenched gas stream. The quenched gas stream is fed to a first stage adsorption vessel of first stage adsorption unit to produce a first outlet gas stream. The first outlet gas stream is fed to a second stage adsorption vessel of a second stage adsorption unit to produce a second byproduct gas stream. The first stage adsorption vessel is regenerated to produce a first byproduct gas stream. The second stage adsorption vessel is regenerated to produce a second outlet gas stream including hydrogen sulfide. Optionally, a portion of the second byproduct gas stream or nitrogen can be fed to the first stage adsorption vessel or the second stage adsorption vessel for regeneration. Optionally, a sales gas can be fed to the second stage adsorption vessel for regeneration. Optionally, vacuum can be applied to the first stage adsorption vessel or the second stage adsorption vessel for regeneration.