INDUSTRIAL PRETREATMENT - TRICKLING FILTER PERFORMANCE AND DESIGN

An 11-month trickling filter pilot study was conducted at a synthetic fiber manufacturing facility. COD removals increased linearly as organ ic loading increased from 2.53-4.90 kg TCOD/m(3)/d (158-306 lb TCOD/1, 000 ft(3)/d) and then reached a constant maximum from 4.90-5.78 kg TCO D/m(3)/d (306-361 lb TCOD/1,000 ft(3)/d). Hydraulic loadings did not s ignificantly affect removals over a broad range of 27.1-70.6 m(3)/m(2) /d (666-1,733 gpd/ft(2)). Four design models were evaluated for their ability to model the data. Two models, including the Modified Velz equ ation, incorporated hydraulic loading as the major independent variabl e, while the other two equations were based on organic loading. The de sign equations based on organic loading modeled the data much more acc urately. For the two organic loading models evaluated, a Monod-like, p seudo-mixed order model gave slightly superior results to the first or der model. In addition, significant stabilization of influent total su spended solids (TSS) was observed. The implications for industrial pre treatment design of trickling filters, as opposed to traditional metho dologies developed largely from municipal treatment data, are discusse d.