Integrated Steam Reforming for Low-Steam Methanol Production
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional methanol production methods face inefficiencies due to the use of excess low-quality steam from steam reforming units, which limits thermal efficiency and requires additional energy for compression, and the lack of effective utilization of regenerative and recuperative burners in the process.
Innovation Solution
Implementing a methanol synthesis unit with compressors driven by gas turbines or combined gas and steam turbines, utilizing bayonet reactors for higher reforming temperatures, and incorporating regenerative or recuperative burners to optimize energy use and reduce steam consumption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If conventional steam reforming units are used to produce steam for methanol production, then steam is available for the process, but thermal efficiency is limited and excessive steam is consumed
Solution Approach 1:
The patent combines the steam reforming unit and methanol synthesis unit into an integrated system where the steam reforming unit serves dual purposes: producing reformate syngas for methanol synthesis and generating steam to drive compressors. This merging eliminates the need for separate steam generation systems and reduces overall steam consumption while improving thermal efficiency.
Solution Approach 2:
The steam reforming unit is designed to perform multiple functions simultaneously: (1) reforming hydrocarbons to produce syngas, (2) generating steam by heating feed water in heat exchangers, and (3) providing thermal energy for the process. This multi-functionality reduces the need for dedicated steam generation equipment and improves overall energy utilization.
2Productivity
If compressors are used to compress reformate syngas for methanol synthesis, then syngas compression is achieved, but additional energy is required for compression
Solution Approach 1:
The system uses its own produced steam to drive the compressors needed for syngas compression and methanol synthesis. The steam reforming unit generates steam that is then utilized to power the compressors, creating a self-sufficient energy system that reduces external energy requirements and improves overall productivity.
3Loss of energy
If regenerative or recuperative burners are implemented in the steam reforming furnace, then energy efficiency is improved, but device complexity increases
Solution Approach 1:
The regenerative and recuperative burners preheat combustion air using waste heat from flue gases before the air enters the burners. This preliminary heating action recovers energy that would otherwise be lost, significantly improving energy efficiency. The heat exchangers are positioned to capture heat from flue gases and transfer it to the combustion air stream.
Solution Approach 2:
The system recovers waste heat from flue gases that would normally be discarded to the atmosphere. The recuperative and regenerative burners capture this waste thermal energy and redirect it to preheat combustion air, converting a harmful waste stream into a useful resource that improves overall energy efficiency.
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
Enhances thermal efficiency by reducing steam consumption and energy requirements, allowing for higher reforming temperatures and lower S/C ratios, thereby improving the overall energy efficiency of methanol production.
Implementation Method 1
reforming, in a bayonet reforming reactor tube of the steam reforming unit, reactants comprising steam and a hydrocarbon to produce a reformate syngas
Implementation Method 2
cooling the reformate syngas within the bayonet reforming reactor tube to a second temperature less than the first temperature
Implementation Method 3
generating the steam by heating feed water in at least a first heat exchanger configured to transfer heat from a furnace that heats the bayonet reforming reactor tube
Implementation Method 4
a second heat exchanger configured to transfer heat from the reformate syngas
Implementation Method 5
the regenerative burner or the recuperative burner is configured to preheat combustion air against combustion products of the regenerative burner or of the recuperative burner
Implementation Method 6
heated by a regenerative burner or a recuperative burner
Data Source
AI summary
Syngas is produced by a steam reforming unit with at least one of a bayonet reactor for reforming steam and a hydrocarbon, a recuperative burner, and a regenerative burner such that the steam reforming unit produces little or no steam in excess of the steam reforming process requirements. The syngas is then converted to methanol in a methanol synthesis unit. Compressors for the synthesis unit are driven by higher efficiency drivers than are possible using the low temperature steam conventionally exported from a steam reforming unit.