margheritaLoose plastic media for trickling filters and anaerobic digesters OPERATING PRINCIPLE The greatest source of water pollution is the discharge of organic substances. Nature spontaneously reacts to this attack by producing bacteria that decompose the organic waste. However, these bacteria may have to face competition for the oxygen they need from other forms of aquatic life and suffer considerably if there is not enough oxygen. The crucial factor for healthy water is, therefore, oxygen. In fact, the degree of pollution is expressed using the term BOD: biological oxygen demand. Percolating filters are designed to satisfy this demand for oxygen before the water is sent into natural waterways, thus avoiding the harmful effects of these substances in rivers, lakes and seas. margherita percolator media is the result of the evolution of stone percolators that have traditionally been used for biological purification to great effect. This material can be used to create higher structures, less likely to become clogged up and with a more consistent specific surface area. MAIN ADVANTAGES S high efficiency S low energy consumption S hard to get clogged up S low capital outlay S easy installation S low maintenance S regeneration of existing plant max diameter of single unit 175 mm height of single unit 50 mm unit weight 100 g circa equivalent weight per square metre 50 kg circa specific surface area 120 m2/m3