51 results about "Preferential flow" patented technology

A fuel cell diffusion layer providing a preferential path by which liquid reactants or byproducts may be supplied to or removed from a direct oxidation fuel cell is described. The modified diffusion layer will be typically on the cathode side of the fuel cell and its use is to eliminate or minimize flooding of the cathode diffusion layer area, which is a performance limiting condition in direct methanol fuel cells. In accordance with one embodiment of the invention, the diffusion layer includes a substrate that is coated with a microporous layer. A pattern may be embossed into the diffusion layer, to create preferential flow paths by which water will travel and thereby be removed from the cathode catalyst area. This avoids cathode flooding and avoids build up of potentially destructive pressure by possible cathodic water accumulation. This also provides a means for collecting cathode water for redirection In accordance with another aspect of the invention, the preferential path is established by applying a thicker microporous layer to the carbon cloth or carbon paper and drying it in such a fashion so that when it dries, the surface of the microporous layer cracks to provide the pathways.

A reactor for two-phase reaction, in particular for urea synthesis at high pressure and temperature of the type wherein a co-current flow of a gaseous phase and a liquid phase takes place, comprises a substantially cylindrical vertical external shell (2) in which is supported a plurality of superimposed horizontal perforated plates (6a-6e) in mutually spaced relationship and at least one opening (12a-12e) for liquid flow being defined in correspondence of each of the perforated plates. Advantageously the openings (12a-12e) for liquid flow are mutually offset so as to obtain a substantially zigzag preferential flow path for the liquid phase in the reactor.

The invention discloses a method for controlling earth surface water and soil loss of an underground layered mineral product mining subsidence area. According to the method, according to the soil body stress distribution or the deformation feature difference caused by the elevation change of a mining area ground surface subsidence basin, the water physical property of a ground surface soil body in different water containing conditions is utilized, the soil body plasticity is improved, pull cracks of a soil body are reduced, and therefore the depth perpendicular infiltration function caused by the cracks in the soil corrosion process is achieved. On the mining area ground surface, the soil body water containing rate is adjusted through an auxiliary technology for quantitative water spraying, the ground crack development degree of an expanding time zone of the mining subsidence basin is controlled, and the water and soil loss acting degree caused by the crack preferential flow action is lowered. Compared with the prior art, the method has the advantages that a large machine is not needed for construction, the input is low in the mine lot environmental governance technology method, and the governance cost is low; the ground surface soil body does not need to be chemically improved through the method, the micro-ecology environment in the soil body cannot be damaged, and the method is suitable for the fragile ecological environment in a mine lot.