Abstract: A fuel preferably pelletized and method of forming a fuel including a quantity of a natural particulate cellulosic material and a quantity of a particulate biosolid material from a bioslurry effluent derived substantially from fats, oils and grease (FOG) found in non-edible food residuals from sanitary sewer drainage (SSD). The biosolid material and the cellulosic material are substantially homogenous, preferably having a moisture content of from about 5% to about 15% by weight and at least substantially minus 5 mesh. A quantity of particulate synthetic polymeric thermoplastic fines material may be added for increased fuel energy content.

Abstract: An air admittance valve assembly for venting ambient air into a system while preventing the escape of gases within the system. A housing includes first and second passageways in fluid communication through a valve seat therebetween. A flat generally thin, flexible, preferably resilient free-floating sealing membrane is positioned for sealing engagement by gravity only atop the valve seat. Ambient air in the second passageway will freely flow into the first passageway and the system at system air pressure less than atmospheric pressure while air within the system is prevented from flowing outwardly therefrom through the valve assembly.