Max-Ion Engineering Services

The fact that dissolved air flotation clarifiers or dissolved air flotation units (with 3 - 5 minutes of detention time) can replace sedimentation (with 2 - 3 hours of detention time) for clarification, has been overlooked by environmental engineers for many decades. Modern high rate DAF clarifiers have advanced to such an extent that they could overshadow conventional settling clarifiers in wastewater treatment.

max-ion hydraulic loading has increased from 1 L/m2.s to 2.5 L/m2.s and for a triple stacked unit to 7.5 L/m2.s. The detention time has decreased from 30 minutes to 3 minutes. Air dissolving is improved and now requires only 10 seconds retention time in the air mixing tube instead of the previous 60 seconds. . DAF PROCESS maxion DAF are circular in shape, ranging in diameter from 1.2 to 21.3 meters and a liquid depth of only 0.65 meter. The complete set up consists of a flotation tank, feed pump, pressure pump, compressor, air mixing tube, chemical feed system and a spiral scoop for collection and removal of floated sludge.

The inlet, outlet and sludge removal mechanisms are contained in the central rotating section. This section and the spiral scoop rotate around the tank at a speed synchronized with the flow. The system is operated in the recycle flow pressurization mode where a portion of clarified effluent (25 - 30 percent) is continuously recycled from the collection tank to the air mixing tube at about 6.5 bar pressure. After pressure release, the aerated water is mixed with the influent flow just before the inlet to the distribution duct that moves with the same velocity, but in opposite direction to the incoming flow thus creating a quiescent state in the flotation chamber. Fine bubbles generated in this manner attach to the suspended particles and make them float to the surface.

The spiral scoop takes up the floated sludge, pouring it into the stationary center section where it is discharged by gravity. Clarified water is removed by extraction pipes, which are attached to the moving center section and discharged. Wiper blades attached to the moving distribution duct scrape the bottom and the sides of the tank and discharge settled sludge into the built-in sump for periodic purging. The variable speed gear motor drives the rotating elements and scoop. Electrical current for the gear motor is fed from a rotary contact mounted on the central shaft.AIR MIXING;The separation efficiency of Total Suspended Solids in a DAF cell depends substantially on the generation of uniformly sized microscopic air bubbles. A part of the clarified water, generally 25 to 30% of the feed rate, is pressurized through a centrifugal pump to about 65 meter head and let into a cylindrical Air Mixing Tube through a nozzle at one end. The nozzle is so oriented inside the tank that the jet of water churns spirally along the inside wall of the tube forming a vortex along the central axis of the tube.
Into this tube is brought compressed air which passes through a microscopically porous medium placed adjacent to the inside wall of the tube.
The tube produces a saturated air-water mixture because the rate of absorption of any gas in a liquid is directly proportional to the pressure in which the dissolution takes place.
The air-water mixture that comes out of the other end of the tube passes through a pressure release valve where the pressure is reduced to the level of the incoming wastewater feed. At this stage, air bubbles of 30 - 50 microns are produced profusely which get released into the wastewater thereby giving the necessary buoyancy to the suspended solids to rise to the surface of the water in the flotation tank.
ZERO VELOCITY;A quiescent state is an absolute necessity for good flotation. This is achieved by ensuring zero velocity of the wastewater when it enters the flotation tank.

Model Name/Number	rotameter
Tube Body Construction	Glass

Rotameter are designed for the accurate measurement of rate of flow for liquids and gases. The rotameter is mounted on vertically. A complete rotameter installation consists of tapered glass tube and shielded from all the sided with clear front visibility.

FEATURES:-

· Complete flow range from min.10 LPH upto a max. of 60000 LPH. Available from 1/2" end connection to 2 1/2" end connections

· Available in on-line (threaded/flanged connections) and panel mounted (with elbow BSP male threaded) connections for all ranges

· Single piece, injection molded polycarbonate body

· Tamper proof sticker for graduation

· Enhanced meter readability using precision textured light admitting surface on the rear of the body

· Each rotameter is factory calibrated

· Each rotameter from range of 2400 LPH to 15000 LPH is Hydro Tested at 8 kg/cm2 pressure

TECHNICAL SPECIFICATIONS:
· Accuracy - ± 2% of FSD

· Tube Body Construction - Moulded polycarbonate

· End connectors - ABS

· O-Ring Material - Nitrile

· Float Material - SS316/PVC

· Temperature Limit - 70°C

· Test Pressure - 10Kg /cm2