Current status of the rotating belt filtration (RBF) technology for municipal wastewater treatment

Abstract

Rotating belt filtration (RBF) is a technology designed for the removal of suspended solids, and effluent organic matter from wastewater that has been recently undergoing intensive development and testing. Generally, RBF can remove solids to meet Ten State Standards (‘Primary settling of normal domestic wastewater can be expected to remove approximately one-third of the influent BOD5 when operating at an overflow rate of 41 m3/(m2 d) [1,000 gallons per day/square foot]’) and European council directive standards (at least 50% total suspended solids (TSS) and 20% Biological Oxygen Demand (BOD) removal). Recent testing have also shown that, when a polymer is added upstream of the RBF, solids and organics removal is significantly enhanced. Advantages of RBF include reduced space requirement, ability to support small mesh without clogging, reduced civil engineering site work, and modular construction allowing for reduced design work, faster installation, and ease of plant expansion. Additional site-specific advantages may include reduced capital and operation costs, and energy savings (e.g. reduced aeration costs following the addition of primary solids removal by RBF against the baseline case where primary solids removal is not practiced). As a matter of fact, when RBF is operated as a pretreatment to remove 50% of the incoming TSS prior to the biological aerated tank, a significant decrease in power consumption ranging from 22 to 28% can be expected if compared to the case where no primary treatment is used. This paper focuses on the current status of development of the technology and provides a literature review of recent experimental studies focused on testing RBF.