The MBR Book: Principles and Applications of Membrane

168 The MBR Book
membrane plants operating or under construction worldwide, treating a total flow
of �250,000 m 3 /day (Kennedy and Churchouse, 2005).
A logical alternative to the double-deck design is the creation of a single elongated
membrane panel, therefore having a longer airflow path and a larger membrane
area. Kubota have recently developed a larger module (type 515) in which the membrane
panels interlock to create the module without the need for a separate housing
to slot the panels into. Each membrane panel (1.5 m � 0.55 m, providing an effective
membrane area of 1.25 m 2 ) contains internal channels connecting to a moulded
permeate manifold section. When the panels are joined together, these sections form
the permeate manifold. This design removes the need for separate manifolds and permeate
tubes and reduces the complexity of the housing (Fig. 4.5). In addition the
greater surface area per panel leads to reduced power consumption for aeration,
SAD m being 0.34 Nm 3 h �1 air/m 2 membrane area. This represents a significant
reduction in aeration demand, and thus energy consumption, from the original
single-deck ES module for which the figure is 0.75 (Table 4.1). This then leads to a
lower SAD per unit permeate volume (SAD p, volume of air per volume of permeate,
Figure 4.5 The Kubota EW module
Table 4.1 SAD m figures in Nm 3 /(h m 2 ) for Kubota modules
EW EM EK ES
Standard 0.34 0.48 0.53 0.75
SAD is given as airflow per unit membrane area (Equation (3.6)).