Membranes equipment configurations

Northwest Power Systems obtained U.S. Patent 5,997,594 in 1999 for a Steam Reformer with Internal Hydrogen Purification. This process is based on a steam reformer that has a membrane separation system and a methanation system in close proximity to the area in which the reforming reaction occurs. Several potential equipment configurations are described in the patent. 

In a simple membrane reactor, basically the membrane divides the reactor into two compartments the feed and the permeate sides. The geometries of the membrane and the reaction vessel can vary. The feed may be introduced at the entrance to the reactor or at intermediate locations and the exiting retentate stream, for process economics, may be recycled back to the reactor. Furthermore, the flow directions of the feed and the sweep (including permeate) streams can be co-current or counter-current or some combinations. It is obvious that there are numerous possible process and equipment configurations even for a geometrically simple membrane reactor. 

Brodie crystallizer-purifier, 545, 547 Kureha purifier, 545,547 multistage, 543 MWB process, 543,545 Phillips process, 544-546 Schilaknecnt column, 543,544,546 TNO bouncing ball process 545.547 Melt purification. See Melt crystallization Membranes, 631,632,641 applications, 632 cellulose acetate, 635 equipment configurations, 632 gas permeation,633,644 hollow fiber, 632,633,641,643 performance, 646 Permasep, 641 olate and frame, 638 Prism, 633,643 properties, 635,636 structures, 632 tubular, 638,639 types, 635, 636... 

Membrane Processes 631 Membranes 632 Equipment Configurations 632 Applications 632... 

Islam (2005) wrote a masters thesis on the purification of water contaminated by As, using the HVR (house-hold water purifier) system developed by the Swedish HVR Water Purification AB Company. The system includes a heated feed tank, a membrane module equipped with two flat membranes (total membrane area, 0.2 m ) and a water chiller. The membrane distillation configuration investigated was that with the air gap (1 mm thick) at the permeate side. 

Gleaning. Fouling films are removed from the membrane surface by chemical and mechanical methods. Chemicals and procedures vary with the process, membrane type, system configuration, and materials of constmction. The equipment manufacturer recommends cleaning methods for specific apphcations. A system is considered clean when it has returned to >75% of its original water flux. 

Aim of this work was to optimise enzymatic depolymerization of pectins to valuable oligomers using commercial mixtures of pectolytic enzymes. Results of experiments in continuous and batch reactor configurations are presented which give some preliminary indications helpful to process optimisation. The use of continuous reactors equipped with ultrafiltration membranes, which assure removal of the reaction products, allows to identify possible operation policy for the improvement of the reaction yield. 

The volume of the equipment for a given area requirement depends on the chosen membrane configuration. For example, spiral wound membranes have a typical packing density of around 800 m2-m 3, whereas the packing density for hollow fiber membranes is much higher, at around 6000 m2-m 3. 

For insenion inio separation equipment. frequently with large throughputs, membranes are available in several configurations (lithe tubular form ll in. 12.5 mm) is common (2) hotlow-tiher (3) pliue-ami-t rame ami (4) spiral wound. The Paulson reference covers membrane formats in considerable detail. 

FIG. 8 Schematic diagrams of different arrangements for an ED unit equipped with bipolar membranes (bmp) coupled to anionic (a) and/or cationic (c) membranes (A) three-compartment configuration (B) two-compartment configuration using bipolar and cationic membranes (C) two-compartment configuration using bipolar and anionic... 

Microfiltration units can be configured as plate and frame flat sheet equipment, hollow fiber bundles, or spiral wound modules. The membranes are typically made of synthetic polymers such as Polyethersulfone (PES), Polyamide, Polypropylene, or cellulosic mats. Alternate materials include ceramics, stainless steel, and carbon. Each of these come with its own set of advantages and disadvantages. For instance, ceramic membranes are often recommended for the filtration of larger particles such as cells because of the wider lumen of the channels. However, it has been shown that spiral wound units can also be used for this purpose, provided appropriate spacers are used. 

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