Microscreening sizes

Tables 1 and 2 (10) summarize the microscreen sizes available from two manufactures. A schematic of a microstrainer appears in Fig. 1.

Table 2 Microscreen Sizes from Glenfield and Kennedy ...

This is mechanical separation process for removal of suspended sohds by passing the waste-water through a microscreen. A removal efficiency for TSS is 50-80% depending on the pore size of the microscreen to be used. 

Individual microscreening manufacturers have specific designs and sizes for various types of installations, and much of the design information is proprietary in nature. Design elements required for nficroscreening include (9) ... 

Microscreens. In the course of this research, we came to the opinion that a preliminary screening to remove most of the biomass was desirable. We shall report evaluations of microscreens, or mlcrostralners, for this purpose. These devices have been available for several decades for waste water treatment (11). They are low-hydraulic-head filters, comprised of a screen mounted on a rotating drum. Apertures of available screens range down to micron sizes. Feed is introduced into the drum. Filter-cake control is by backwash with air or a portion of the filtrate, once each rotation, the backwash being caught in a tray. A schematic is shown in Figure 6. 

Particle Sizing by Vacuum Membrane Filtration. In the original plan for this research, particle fractionation by sieving, that is, using microscreens (10, 20, or 30 /xm) and Nuclepore membranes, was anticipated to be a viable means for particle sizing. Microscreens are available in both nylon and stainless steel. The Nuclepore membranes are thin polycarbonate sheets with very uniform round holes etched through them available pore diameters decrease in size from 8.0 /xm. 

When the required particulate removal eflBciency has been determined for each size fraction in the distribution, the technical feasibility of available solids/liquid separation processes must be evaluated. Such a screening procedure will provide the framework for determining the extent of analytical modeling or pilot plant studies needed to develop process design criteria. The solids/liquid separation processes used in water and wastewater treatment exploit the physical-chemical properties of the particulates to achieve rapid and therefore economical separation from the treated water. Microscreening devices remove most particulates with at least one dimension larger than the minimum opening in the... 

---