Mass transfer calculations / output:

Min., Avg. & Max. values of SOTE%, design air flow for blower capacity sizing,

No of diffuser needed, diffuser product selection & specification, system sizing,

Layouts, lateral piping design & capacity sizing at max. airflow to maintain an air velocity ≤ 15m/sec [1,000 SCFM/min.], Diffuser, lateral air piping, & supports - bill of material generation.

Fine bubble Membrane Materials: EPDM, Silicone, & Polyurethane - Scale 1 - 10 (10 is the best)

Expected diffuser membrane life > 10 years; reusable diffuser body – replace only membrane

Allowing for 20% to 40 % energy conversation / utility cost savings over the Yr. 1 to yr. 20+ operating cycle enabled by:
• Up to 16:1 system turn down capability
• Organic loading driven process controls and optimization
• Separate oxygen uptake / aeration from mixing energy for suspended solids

8:1
Based on nutrient loading, hydraulic flow, temperature patterns:

• 2:1 - residential diurnal
  +
• 4:1 - annual and Yr. 1 to yr. 20+ projected
  +
• 2:1 - volatility i.e. extreme weather events; seasonal industries: agriculture, hospitality

• Diffuser grid balancing assures that an aeration grid stays uniform & convers the entire aeration gird food print at all design airflow condition from min., avg. to max.
• It is achieved by a uniform back pressures / a airflow restricting orifice of each diffuser devices. Where orifice size it determined by the minim of the entire design airflow range.

System turn down range

Disc Diffuser Grid

• Better system control on biological activity and oxygen control to the loading entering the basin. A diffused air system can provide higher oxygen transfer capacity / time period and over a wider system oxygen uptake range / system turn down
• Energy conservation is important in today’s world. Fine bubble membrane diffusers are 30-60% more energy efficient per HP provided / have a 2 to 3 x higher SAE [lb. O 2 /hr/hpwire] than mechanical aeration systems. Especially with variable loading to the plant.
• Redundancy of diffuser design vs mechanical design. A diffuser system can be provided with multiple levels of redundancy for system operations staff vs a mechanical system that has limited redundancy.

Fine bubble vs mechanical aerators – kWh to lbs of oxygen

• Older mechanical aeration systems become oxygen deficient as they achieve loading capacity limits.
• For most plants, the load is entered into the plant in 16 hours vs the 24 hours in a day.
• Therefore, the amount of oxygen available for the biological system should be designed on 16 hours and not 24 hours.
• A system design based on average plant loading/h per 24 hours will become oxygen deficient from mid-morning to late afternoon (diurnal peak loading hours) starting at or greater than 75% actual loading vs. planed max. capacity.
• A system design based on average plant loading/h per 16 hours will provide sufficient plant capacity regardless of the time of day

The planning process should also focus on:
• ≥ 6:1 system turn down of the aeration basin and all of its aggregates – 8:1 recommended – especially of the fine bubble aeration diffusers & blower system
• nutrient loading driven process control scheme – OxyProcess TM
• Separation of oxygen uptake / aeration from mixing energy for suspended solids

8:1
Based on nutrient loading, hydraulic flow, temperature patterns:

• 2:1 - residential diurnal
  +
• 4:1 - annual and Yr. 1 to yr. 20+ projected
  +
• 2:1 - volatility i.e. extreme weather events; seasonal industries: agriculture, hospitality

Daily Process Demand

Ambient air and water temperatures influence the oxygen solubility in water [mg/l] & the oxygen concentration [ppm] in ambient air.
I.e. @ sea level:
Dissolved O² in water: 9.2 mg/l @ 20^o C; 7.4 mg/l @ 30^o C
O² Concentration in ambient air: 20.3 ppm @ 23^o C; 19.9 ppm @ 30.5^o C

The O 2 yield of the i.e. blower per m 3 [ft 3 ], or a mechanical aerator system and the capacity of dissolved O 2 in water will decrease with increasing temperatures. Potential violation to discharge permit limits.

The plant may become oxygen deficient reducing its nutrient removal capacity, effluent water quality will decrease, discharge permits limits potentially will not be met.

Solutions:
• Short term: The OxyPOD TM system
• Long term: Increase system turn down capabilities, OxyProcess TM

• Yes, OxyLift TM has no retrievability limitation by basin geometry
• Rectangular, round, toroidal, and square
• Bridge or wall mounted

OXYLIFT RETRIEVABLE – NO LIMIT BY BASIN GEOMETRY

• The minimum is 3%
• Recommended 7 % or greater
• The maximum possible warries form diffuser type of with a disc diffuser system has the lowest maximum. A diffuser floor coverage of > 40 % can only be achieved with the OxyStrip TM & Dual-Air-Control TM diffuser systems.

• Min. Air Mixing req.: 2.0 to 3.0 Nm 3 /h per m 2 of tank bottom area
• Min. Air Mixing req.: 0.12 to 0.18 SCFM/ft 2 of tank bottom area
• The higher airflow / tank bottom value is needed for shallower tanks

• 20.0 to 30.0 SCFM / 1,000 ft 3 of liquid - subject to tank depth & TSS levels
• 115 to 170 Nm 3 /h / 100m 3 of liquid - subject to tank depth & TSS levels
• Coase bubble mixing requires up to 2.5 higher blower capacity and energy consumption than fine bubble mixing
• Fine bubble mixing offers non clog protection as added benefit
• JAEGER offers check valve options for its coarse bubble systems as well