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requires slight overcapacity, wherein the excess spills onto a horizontal overfeed conveyor. Overfeed is conveyed back to the pile. The outfeed conveyor head, the entire distribution conveyor and the entire overfeed conveyor are serviced by ladders and platforms. c) At the base of each dryer feed hopper a rotary (airlock, B-5) feeder meters the classified biomass into the dryer intake chute. The dryers are parallel flow, direct heating, rotary drum type and are mounted at a slight incline so that the feedstock slowly progresses the length of the dryer as the drum rotates. The required moisture removal is achieved by adjusting the rate of drum rotation (retention time) or the rate of fuel consumption (temperature) . The heat source is a direct connected firing chamber with two burners mounted opposite the rotary dryer. The primary burner fires blended fuel oil . A backup burner is included to fire propane if fuel oil pumps fail . The primary and drying air are ducted out of the dryer and directed through a cyclone and baghouse via the induced air fan. Information regarding fuel use and emissions is found in Section 2.1.3. Dry material is discharged to a drop out chamber and is conveyed by reversing screw (fire dump screw) to a common hopper equipped with a rotary airlock. The fire protection function of the reversing screw is discussed in Section 2.3.7. d) Secondary classification is by means of conveying the dryed material into one of four seperate bins. The dried biomass is collected by a pneumatic conveyor system (C-6) at four points: 1) a common fire dump screw hopper, 2) the cyclone hoppers (one for each dryer), and 3) the baghouse. This material is discharged into one of the four classifying bins (D-9) . Since reduction and drying are batch operations, each bin will contain biomass of certain agglomeration and heating value properties. All ensuing operations are continuous duty and depend upon the feed rates from each of the four bins. Each bin outfeed is by varible speed screw conveyor to a common collecting belt conveyor. e) The collecting conveyor empties into another single deck shaker screen, or finishing screen (D-7), which eliminates any material which could damage the briquetters. A bypass chute dumps the "overs" to a concrete bunker. The screened biomass is held-up in a surge bin prior to being fed into a twin screw conveyor which both mixes the biomass and delivers it to the briquetter distribution conveyor. This is a flight conveyor which, like the dryer infeed conveyor, maintains each of the feed hoppers to the three• briquetters full at all times. The overfeed is carried back to the surge bin by two small return conveyors. Biomass is force-fed in the briquetter (E-6) through matched dies 5