Patent ID: 11045769

Abstract:
A submerged membrane unit has air diffusers located outside of the membrane area in plan view. The diffusers may be mounted in or below a diffuser case. The diffuser case may have walls to direct bubbles towards the membranes. The diffusers may be drop diffusers, for example as in a single drop diffuser assembly. The membrane unit may have polymeric or ceramic membranes, for example ceramic flat plate membranes. In an example, a rectangular shrouded membrane unit has a diffuser case below it that is rectangular in plan view but trapezoidal in side view, with drop diffusers located in the corners of the diffuser case. In a process of treating high strength wastewater, for example thickening or digesting waste sludge, a membrane unit optionally with ceramic plate membranes is immersed in the wastewater. The membranes are sparged with bubbles produced below but beside the membrane unit in a diffuser case.