Method for operating a subprocess in an overall process that requires steam

Simple SummaryContent extracted from patent full text and abstract with AI.

This patent describes a method for efficiently operating a steam-requiring subprocess (such as a water-gas shift reaction) within a larger industrial process by using a water vapor-selective membrane. Excess steam that is not entirely consumed in the subprocess is recirculated from the outgoing product gas stream back to the incoming reactant stream via the membrane, which selectively allows water vapor to pass due to a partial pressure gradient. This reduces the need for additional external steam supply and minimizes energy losses associated with condensation and reheating.

Use CasesContent extracted from patent full text and abstract with AI.

• Hydrogen production plants using water-gas shift or steam reforming processes
• Integrated Gasification Combined Cycle (IGCC) power plants with CO2 removal
• Methanol synthesis and reforming units
• Ammonia production where controlled steam balance is critical
• Chemical plants requiring optimized heat and water management in catalytic reactions relying on steam
• Industrial facilities aiming for improved water and energy efficiency by recycling process steam

BenefitsContent extracted from patent full text and abstract with AI.

• Significant reduction in external steam supply requirements, lowering operational costs and energy consumption
• Improved thermal efficiency by minimizing process heat loss through reduced condensation and heat exchanger usage
• Higher overall process efficiency and potential for increased product yield (e.g., hydrogen)
• Enhanced process optimization flexibility, allowing safer and more stable operation, especially in reactions prone to temperature surges or catalyst degradation
• Reduced equipment and maintenance costs due to less reliance on condensers, reheaters, and associated piping
• Greater water conservation and improved water balance, crucial for water-scarce or water-autonomous systems
• Ability to maintain or improve product quality (such as lower CO in hydrogen output) without excessive energy input

Technical Classifications (CPCs)

Inventors & Applicants

Patent Abstract

Operating a water vapor requiring partial process within an overall process, comprises externally supplying water vapor to the partial process, introducing water vapor partial pressure (P1) into the partial process, and directing a product gas stream with a water vapor partial pressure (P2) from the partial process. The water vapor is not completely used in the partial process. The water vapor partial pressure (P2) is greater than water vapor partial pressure (P1). The product gas stream from the partial process is supplied as a feed to a retentate side of a membrane module. Operating a water vapor requiring partial process within an overall process, comprises externally supplying water vapor to the partial process, introducing water vapor partial pressure (P1) into the partial process, and directing a product gas stream with a water vapor partial pressure (P2) from the partial process. The water vapor is not completely used in the partial process. The water vapor partial pressure (P2) is greater than water vapor partial pressure (P1). The product gas stream from the partial process is supplied as a feed to a retentate side of a membrane module and this membrane module leaves with a reduced water vapor partial pressure (P2 - delta P2) as retentate. The reactant gas stream is supplied to a permeate side of this membrane module prior to introduction into the partial process and leaves with an increased water vapor partial pressure (P1+ delta P1) as permeate, which is subsequently supplied to the partial process. The water vapor in the membrane module due to partial pressure gradient for water of at least 10 mbar is transferred from the product gas stream on the retentate side directly to the reactant gas stream on the permeate side over a water vapor selective membrane.