Syngas Split Processing for Methanol Gas and H2/CO Recovery
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods face challenges in producing methanol synthesis gas, H2, and CO from synthesis gas with fluctuating and contaminated compositions in an economical manner.
Innovation Solution
The method involves dividing the synthesis gas into two substreams, where CO is converted to CO2 and H2 through a water gas shift reaction, followed by CO2 scrubbing using an amine-containing detergent, and adjusting the (H2-CO2)/(CO+CO2) ratio to achieve the necessary proportions for methanol synthesis, while utilizing acetylene offgas as a feedstock.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Volume of stationary object
If the synthesis gas stream is compressed to achieve desired product pressures, then the effective gas volume and system component dimensions are reduced, but the compression energy consumption increases
Solution Approach 1:
The synthesis gas stream is divided into two separate substreams (first and second substreams) that are processed through different pathways. The first substream undergoes water gas shift reaction and CO2 scrubbing, while the second substream is used for CO product generation. This segmentation allows optimized pressure management in each branch, reducing overall compression energy requirements while maintaining compact system dimensions.
2Adaptability or versatility
If acetylene offgas is used as feedstock to produce H2 and CO products, then the flexibility of product quantity adjustment is improved, but the complexity of process control increases
Solution Approach 1:
The process employs dynamic flow splitting where the synthesis gas stream is continuously divided into two substreams with adjustable proportions. By dynamically controlling the split ratio and the extent of water gas shift reaction in the first substream, the process can flexibly adjust H2 and CO product quantities according to demand while maintaining stable operation through automated control systems.
3Manufacturing precision
If the (H2-CO2)/(CO+CO2) ratio in methanol synthesis gas is precisely controlled, then the methanol synthesis efficiency is improved, but the process control complexity increases
Solution Approach 1:
The process implements feedback control by continuously monitoring the composition of the methanol synthesis gas and adjusting the water gas shift reaction extent in the first substream accordingly. The control system measures the (H2-CO2)/(CO+CO2) ratio and modulates the steam-to-gas ratio or catalyst activity in the water gas shift reactor to maintain the optimal ratio for methanol synthesis, ensuring high efficiency while automating the control process.
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 allows for flexible production of H2 and CO products with a controlled ratio, reducing system dimensions, absorption costs, and increasing H2 yield, thereby optimizing the use of acetylene offgas and minimizing residual gas compression.
Implementation Method 1
only CO contained in the first synthesis gas substream being converted to CO 2 and H 2 with water vapor mixed into the first synthesis gas substream (water gas shift reaction)
Implementation Method 2
each fed to two separate washing columns for washing out CO 2 with an amine-containing detergent (e.g. MDEA)
Data Source
Figure 1
AI summary
The invention relates to a method for producing a methanol synthesis gas product stream (2), an H2 product stream (3), and a CO product stream (4) from a synthesis gas stream (5) containing H2 and CO, in particular in the form of AOG, the method comprising the following steps: Separating the synthesis gas stream (5) into a first and a second synthesis gas substream (51, 52), wherein only CO contained in the first synthesis gas substream (51) is converted to CO2 and H2 with water vapor mixed into the first synthesis gas substream (51). Both the first synthesis gas substream (51) and portion (52a) of the second synthesis gas substream (52) are scrubbed with a scrubbing agent containing amine (102) in order to elute CO2, wherein the scrubbing agent of both columns in particular is regenerated in a joint column. The methanol synthesis gas product stream (2) is composed of a portion (51a) of the washed, converted first synthesis gas substream (51) and/or the other portion (52b) of the unconverted, second synthesis gas substream (52), and, if applicable, of DWA residual gas (9) and crude H2 (111) such that a ratio of (H2-CO2)/(CO+CO2), as necessary for the methanol synthesis, in particular in a range from 2.0 to 2.1, is established in the methanol synthesis gas product stream, wherein the scrubbed one portion (52a) of the second unconverted synthesis gas substream (52) is utilized for producing the CO product stream (4) and the H2 product stream (3) and the other portion (51b) of the scrubbed, converted first synthesis gas substream (51) is used for producing the H2 product stream (3). The invention further relates to a device for producing the above-mentioned products from a synthesis gas, in particular from AOG, which prior to separation into the two substreams (51, 52) is compressed to a suitable pressure, and downstream, is cleared of unsaturated hydrocarbons and O2.