Steam permeability

For example, if LiD salt is placed in contact with the surface of a stainless steel specimen, the oxide is reduced, allowing increased permeation. If a metal undergoes surface oxidation in the presence of steam, permeability decreases as oxidation proceeds. 

Steam Permeability through the Polymer Electrolyte Hydration of the PBI/PPy(50)coPSF Membrane... 

Cotton textiles or conventional mixed cotton-polyester textiles, the traditional materials for surgical gowns and drapes, meet a number of requirements, such as comfort, drapeability, good tensile strength, steam permeability and steam sterilisability. However, they will not meet the requirements of the new standard, which includes resistance to microbial penetration, resistance to liquid penetration... 

Water- and stain-repellent characteristics combined with air and steam permeability... 

Gas permeability higher than for many other plastics, though steam permeability very low Very transparent (semi-crystalline)... 

The warming up of the mat is performed by the so-called steam shock effect [173,219]. A prerequisite for this is the high permeability of the particle or fiber mat. Higher moisture contents of the face layers and spraying of water sustain this effect. 

Overall board density will strongly affect core layer plasticization and density profile (Fig. 12), as at the highest overall board density a steep density gradient appears between the surface and core layers of the board. This is due to the greater difficulty encountered by the steam to penetrate and plasticize it. At lower density, the greater mat permeability enables a faster steam throughflow of the board, comparable to a steam injection process. The final result is similar as the overall board density is closer in value to both core and surface densities. 

The initial moisture content is a determinant factor in the rate of heat transfer to the center of the core mat [226,227]. At short press closing times the rapid temperature rise occurs at the same time for both lower and higher moisture content percentages indicating that the steam condensation front reaches the core at the same rate and that this is then determined more by local permeability rather than local moisture content. The slope of the rise is similar as it is the balance of horizontal and vertical permeability which controls the rate of steam flow to the core layer. Furthermore, water remains in the surface layer in a quantity such as... 

The results at 75°C are consistent with results of steam foam sand pack floods reported by Muys and Keizer [63]. They observed lower sand pack permeability with increased AOS carbon number. Isaacs et al. reported similar results [64]. 

Effective in reducing permeability in steam swept zones... 

The literature is replete with references to various foaming agents which are employed to lower permeability in steam swept zones. The vast majority of the foaming agents require the injection of a non-condensable gas to generate the foam in conjunction with the injection of steam and the foaming agent [1372]. 

C12 to Ci5 alcohols and a-olefin sulfonate are highly effective with steam foaming agents or carbon dioxide foaming agents in reducing the permeability of flood-swept zones [1372]. 

When drug solutions and containers can withstand autoclaving conditions, this method is preferred to other sterilization methods because moist heat sterilizes quickly and inexpensively. However, judgment must be exercised and experiments run to ensure that the solution and container are permeable to steam. Oils and tightly closed containers, for example, are not normally sterilizable by steam. 

The stationary in situ steam extraction system uses injection wells to introduce the steam, and recovery wells for removing it. Soil permeability is a major factor. Low-permeability soils require a far greater number of wells compared to high-permeable soil, driving up costs. To be effective... 

Uemiya, S., N. Sato, H. Ando, T. Matsuda, and E. Kikuchi, Steam reforming of methane in a hydrogen permeable membrane reactor, Appl. Catal., 67,223-230,1991c. 

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