Abstract: A grate assembly for guiding air into a pile of combustible wood pellets for combustion thereof. The grate assembly includes a structural subassembly having at least two sets of elongate members, a first one of the two sets forming a lower layer for at least partially supporting a second one of the two sets forming an upper layer. The grate assembly also includes a support element attached to the structural subassembly. Each member includes a body at least partially defining one or more channels and a number of holes in fluid communication with the channel(s) to guide air into the pile of the wood pellets.

Abstract: An inexpensive device for removing microorganisms from drinking water includes an Ultrafiltration membrane filter equipped with a pressure regulating mechanism to supply purified water to a suitable low-pressure reservoir equipped with a bi-directional hydrophobic membrane vent filter having a 0.01-0.05-micron pore size. The purified water may be supplied to the storage reservoir at a static pressure in the range of 1 to 8 pounds per square inch.