Membrane-based system

However, industrial applications have been limited mostly because these new membrane-based systems have not been proven extensively at the industrial level and their advantages have not been quantified in industrial terms, as is the case for traditional consolidated technologies. This fact has discouraged industries from applying these systems in large plants. Therefore, demonstration tests are needed in order to be able to fully exploit the commercial potential of the membrane contactor technology. 

Mars [Membrane aromatic recovery system] A membrane-based system for recovering aromatic compounds from aqueous waste streams. The membrane was initially made from a silicone rubber, but later versions used polypropylene glycol entrapped in a porous polypropylene sheet. Demonstrated first at a cresol-recovery plant in Knottingley, UK. 

In addition to the intrinsic limitations of these membrane-based systems, the experimental problems (i.e. solubility, adsorption to plastic surfaces, analytical constraints) are similar as those encountered for cell-based systems. 

Membrane-based systems easy high- or medium throughput low cost only passive diffusion variability/stability of columns (lAM)... 

And now a Specific Example of a Sample Separation and Analytical Membrane Based System - The Glowgrub ... 

In a comparative study of an integrated hybrid membrane-based system with an earlier locally designed RO unit, such system comprises NF, RO, and membrane distillation (MD) subsystems [79]. The comparison is essentially based on using the NF technique in pretreatment section, while the MD was contributed to concentrate the two brine streams from both NF and RO. Thus, high recovery rate of product water is aimed for. The proposed system was economically evaluated and compared with the RO unit. It was concluded that 76.2% water recovery was possible with a water production cost of 0.92 m . ... 

The two key performance requirements that determine whether a membrane technology is suitable for application in a power generation facility are performance capabilities and cost. Performance requirements of a membrane-based system are defined at the system level and often involve target purities for several components in filtered fluid streams. Other performance requirements include reliability and footprint targets. 

The proposed scheme of Pre-combustion decarbonation based on the use of membranes for hydrogen separation is expected to have some advantages over the conventional and commercially ready technology, such as superior efiiciency and reduction in overall plant capital cost. Membrane-based systems may represent a real advancement in state-of-the-art H2 and CO2 capture in such power plants however, their real application is closely hnked to the realization of a membrane module that is economically built and maintained, as well as to the improvement of membrane permeance and selectivity. 

Classical cocurrent separators in two-phase systems generally use dispersive contacting with one phase dispersed as drops (or bubbles). Porous membrane based systems can avoid such dispersive contacting, as we have... 

The description of the extent of separation achieved in a closed vessel for a mixture of molecules is treated in Chapter 1. Chapter 2 illustrates how to describe the separation of molecules in open separators under steady and unsteady state operation a description of separation for a size-distributed system of particles is also included. Chapter 3 introduces various forces developing species-specific veiocities, fluxes and mass-transfer coefficients, and illustrates how the spatial variation of the potential of the force field can develop multicomponent separation ability. The criteria for chemical equilibrium are then specified for different types of multiphase separation systems, followed by an illustration of integrated flux expressions for two-phase and membrane based systems. 

The terminal deionization step in the membrane-based system includes the use of EDI technology. Industrial-scale EDI devices are available in two major... 

G. Krishnan, I. S. Jayaweera, Fabrication and scale-up of polybenzimidazole (PBI) membrane based system for precombustion based capture of carbon dioxide , 2011 NETL C02 Capture Technology Meeting, August 2011. 

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