Sewage Processing Plants – The particle size distribution and particle charge properties of solids in the final settling tanks International Environmental Technology Vol. 11 Issue 6 Nov/Dec 2001 Wolfgang Schubert, F. Wolfgang Gunthert, Renate Hessemann …The theoretical sedimentation time of a 1-micron particle is around 210 days; for a 10-micron particle it is 50 hours; and for a 100-micron particle 30 minutes. Therefore in the final settling tanks, particles smaller than 100-micron that have sedimentation times of several hours may not settle-out completely…
Figures 1 and 2 show, as an example, the measured particle size distribution (from 6 to 3000-micron) in the final settling tanks of an activated sludge process and from a fixed bed plant respectively… * Area Distribution representative of total particle size spectrum
“Selective Separation”
Baleen – the “missing link” Micron Scale Stage Process 10,000 1000 100 10 1.0 0.1 0.01 0.001 Primary Secondary Tertiary Coarse Screening Fine Screening Baleen Filtration LEFT TO RIGHT SEEMS MORE LOGICAL TO ME...... Micro filtration Ultra filtration Nano Filtration Reverse Osmosis
The Baleen filter…
Modular design…
Industry-Application ’05 ’10 ’20 ’40 ’80 ‘160 Baleen’s flow handling capability (kL/hr) within Municipal applications… Baleen-Model Industry-Application ’05 ’10 ’20 ’40 ’80 ‘160 Raw sewage influent (post grit screens) 10 35 100 200 400 800 Secondary effluent (post clarification) 15 50 150 300 600 1200 Stormwater run-off (post GPT) 20 70 1600 The above tabulated performance figures refer to separation of visible, settle-able matter* *Subject to site survey
Baleen (inline micro-screening) Vs Settling (clarifier retention) Objective: Separation of visible constituents from storm water influent Flowrate (kL/hr) Baleen Model Volume (<150-micron) Clarifier (<1hr-retention) 200 ‘20 32 m3* 260 m3** 1600 ‘160 135 m3* 2080 m3** Outcome: Baleen offers “absolute” retention to a given micron-rating * Includes minimum working clearance **Includes minimum civil clearance (1.3x)