Aerobic waste water treatment reactor incorporating air inlet within lower layer

摘要

A standing waste water anaerobic treatment vessel (1) has an upper waste water inlet (14) and an outlet (26) at its base. A perforated base plate (4) sub-divides the vessel into a reaction chamber (30) and a lower chamber (3), and discharges treated waste water to the outlet (26) via a number of jets (4a). A pipe (20) discharges compressed air into the reaction chamber (30). The perforated base plate (4) is covered by a granular layer (2) under a finer granular layer which acts as a substrate for micro-organism growth. The novelty is that: (a) an air distributor (5) connected to the air inlet (20) is located within the lower layer (2) of grain substrate; (b) the lower layer (2) consists of rough and abrasion-resistant hard PVC grains of diameter less than 10 mm dia., and with a specific weight in the range 1.1 to 2 g/cm<3>, pref. 1.4 to 1.5 g/cm<3>; (c) the inter-particle gaps between the PVC grains are filled by 2-10% by weight pref. 5% by weight fine-grained chalk; (d) the PVC is free of any softening agent; (e) the density of the PVC grains is 500 to 1,000 kg/m<3> pref. 750 to 800 kg/m<3>; (f) the PVC grain size is in the range 2-5 mm.