Manufacturer: Air Diffusion System

Type: fine bubble aeration

Location: Chicago, IL

Products: LTC tubing, LDC tubing, LWA 1.5 tubing, LWA3 tubing, LWIM tubing, LWFT tubing, LTC disk module, LWA disk module

Illustration: Amity, OR

Air Diffusion System (ADS)® fine bubble aeration concept was first developed in the 1960's. This unique technology was developed to duplicate a “Rolling River” that provides circulation of oxygenated water for treatment of water and wastewater in the same way as a natural stream. Natural solutions to modern pollution have made this process very attractive to any community, engineer or state agency. Aquatic life forms, thriving in the oxygenated environment, quickly reduce contamination in lake water and converts wastewater and organic sludge into water, carbon dioxide and inert ash. With almost fifty years of successful installations, this technology has been proven to be simple, very energy efficient, and long-lasting.

Each system is engineered to meet individual treatment needs. Controlled fine bubble systems are assembled in two basic formats: Linear and Disk Module. The traditional linear tubing is commonly used for flat bottom water treatment systems. The new “Billion Bubble per Day” Disk Module is best suited in treatment with high oxygen demand or bodies of water with irregular shapes and bottoms. These biological treatment systems can be used for a wide variety on applications: domestic and industrial wastewater, lakes & reservoir, golf course ponds, aquaculture, and even ice melting system to prevent ice damage to docks, boats or concrete structures. (cf. table below).

How it works ?

The Aerated-Facultative Lagoon Process is a natural solution to man made pollution. ADS purifies water the same way nature does. The natural rolling action of a stream is a process that has been going on for thousands of years. As the top water cascades to the bottom and bottom water moves to the top, it brings life supporting oxygen from the surface to the bottom promoting scavengers to digest organic build up and convert soluble wastes in the water column.
ADS can meet all existing or proposed effluent regulations very cost effectively without the use of any chemicals.

ADS Fine Bubble Diffuser Tubing

The diffuser tubing is composed of a low density polyethylene (LDPE) containing more than 2% Carbon Black :

  An encapsulated wire-keel is located at the bottom of the tubing to keep it in an upright position and to provide the required ballast to keep the tubing submerged with full air flow
  Integral ballast eliminates need for concrete or steel weights
  Surgically produced air-cuts are located on the top and/or sides of the tubing spaced from 38mm (1.5") to 600mm (24") apart

The air-cuts have a width of approximately 25 microns that require 14 kPa (2 PSI) more than hydrostatic pressure to allow uniform distribution across the length of the tubing. These precise air-cuts act as a check valve to prevent the entry of foreign material to the inside of the tubing. The pressure drop across the air-cuts is critical to ensure the following properties:

  The diffusers emit a uniform air pattern even if the pond bottom is not perfectly level (due to sludge accumulation or intended bottom slope)
  A bottom elevation variation of up to 0.5m (1.5 ft) will not compromise the bubble pattern.
  If the blowers are shut off for a period of time, the die-cuts act as one-way valves and will allow water but little or no solids to enter the diffusers

Exceptional Oxygen Transfer Efficiency

The Mass-Gas Transfer of oxygen into water is directly proportional to the bubble contact time in the water. Controlling the diameter of these tiny bubbles is very important for highest oxygen transfer and excellent pumping of the water. Both of these features will drastically reduce energy costs when compared to other aeration devices.

As energy costs increase, and levels of treatment become more stringent, ADS fine bubble process becomes more and more attractive. It’s simple, bigger bubble slip through the water quicker than tiny bubbles. Turbulence created by large bubbles = wasted energy; and Laminar flow created by fine bubbles = outstanding energy efficiency. The size of bubble and the location of the diffuser will directly affect the HP and the costs to treat the water.

When compared to other diffusers over a 20 year time period, ADS has an exceptional track record and the energy saved often pays for the system within several years. Independent ASCE certification of ADS produces excellent oxygen transfer efficiency and minimizes electrical costs. The bubbles produced by ADS range form 1/10” to 1/50” diameter and rise at approximately 0.8 ft/sec, providing the highest oxygen transfer efficiency in the aeration industry (3% per foot of WD).

Optimal Coverage Aeration

Lagoons are designed to operate in series. ADS aeration tubing incorporates tapered grid coverage aeration, which allocates the amount of air based on the oxygen demands per each basin. This tubing releases a “curtain of air perpendicular to the flow that prevents of short-circuiting.

The aeration lines are spaced close together at the front of the cell to allow for oxygen where there is more food. The aeration lines are spaced further apart as less air is required which results in effective solids settlement while maintaining aerobic conditions. Full aerobic conditions are important to allow for ammonia removal and to prevent odors.

Applications

ADS fine bubble aeration diffuser tubing may be used for:

    Lake and Reservoir
    Municipal and industrial wastewater treatment
    Industrial cooling ponds
    Water quality management and restoration in raw water reservoirs, lakes, streams, canals and storm water retention basins
    Sheet ice melting and frazil ice reduction

Results

Secondary & tertiary treatment (BOD & TSS ± 30 mg/L)

ADS fine bubble aeration systems are designed to fit into existing lagoons, generally without dewatering and any other types of modification. Their very high efficiency and specific design ensure minimal operating costs.

ADS has successfully installed energy efficient complete mix lagoon technology for increased treatment capabilities, in excess of 300% of the normal load of a conventional partial mix aerated lagoon.

Advanced treatment (BOD < 10 mg/L, TSS < 20 mg/L, Ammonia < 5 mg/L, TAN < 1mg/L, TP < 0.5mg/L)

Water quality based effluent limitations are getting more stringent and aeration alone can sometimes not be enough to reach permit level. ADS constantly develop new technologies to improve lagoon processes and bring hardware innovations.

The AMTS (Advanced Microbial Treatment System) bring the latest technologies together to provide one of the best treatment available and warranted.

AMTS is unique and provide multiple benefits:

  Full advanced treatment levels for BOD, TSS, NH3, TAN, TP
  Easy to install in a brand new construction
  Easy upgrade of existing lagoons: no dewatering, no sludge hauling.
  Low energy cost due to excellent oxygen transfer
  No sludge handling more than 25 years
  Reduce land aera requirements
  Minimal operational cost: only 1 moving part.
  Performance Warranty for 5 years (unmatched in the indutry)